# Using Li-ion cells in LED flashlights safely



## JBorneu

Ahoy there

I created this guide because I felt we lacked one single comprehensive guide which tells newbies how to use Li-ion cells in a safe manner in their LED flashlights. Now I know why: At least the "comprehensive" part is impossible.

I'm not an expert myself, but I have picked up quite a bit from CPF and other sources. If you see mistakes, typing errors, language errors, dangerous things or do not agree with anything in this guide, tell me so. If you see something which is really dangerous and you have moderator powers, feel free to correct it before somebody who doesn't know better does it and hurts himself. In that case, please be so kind to inform me of what you corrected. I'm not a native English speaker, so feel free to inform me about any spelling / grammar errors you find. It would probably be best to correct spelling / grammar by sending me a PM so we don't clutter this thread up with the fine nuances of the English language.

*Using Li-ion cells in LED flashlights safely for newbies*

This guide is intended for Li-ion newbies (not the member Newbie, who is one of the battery safety experts here on CPF and has forgotten more about cells than I will ever know). You’ve come to CPF and you discovered Li-ion cells and LED lights which use them and you want to learn how to use them safely. This guide is specifically aimed at LED lights, using Li-ions in incandescent lights requires more care and has its own thread in the incandescent forum. If you follow this guide you will be safe. That is not a legal guarantee. By reading past this point you agree to these things: You will not sue me no matter what happens when you follow the advice from this guide and everything you do is completely your own responsibility.
Take the time to read this all, it’s a lot, more than I expected before I started typing, but you need to know what you’re doing in order to do it in a safe manner.

*1 What Li-ion cells are we talking about?*

There are several kinds of Li-ion cells. In this guide I will only talk about what most people call Li-ion cells: Lithium Cobalt Oxyde cells, which have an average voltage of 3.7 volts.
Three reasons: 1) These are the most commonly used cells in LED flashlights. 2) By the time you need to use other chemistries you will probably have some experience with Li-ion cells and should start to do your own research. 3) I don’t know enough about the other Li-ion chemistries. So, from here on, when I’m talking about Li-ion cells in this guide, I am talking about Lithium Cobalt Oxyde cells, the kind which is in you cellphone, laptop, MP3-player, GPS, cordless drill etc. and which carries the most risk as far as I know.

*2 Risks? What risks? Should I worry?*

Explosion. Fire. Horrible burns, lost fingers and fleshwounds. That’s what we all want to avoid.
When you seriously abuse a Li-ion cell it gets angry. When a Li-ion cell gets angry it becomes a terrorist cell and it will “vent with flame” (AKA explode). (Read the very entertaining story of Shorty and Longman for the origins of “terrorist cell”, although the one in the story is a primary lithium cell. Don’t confuse primary lithium cells with rechargeable Li-ion cells; they are 2 completely different things.)
Remember the fuss about exploding laptop and cellphone batteries, the huge product recalls, the lawsuits, the martian invasion to rid us of unsafe cells? No? Well, I might be imagining part of that. But rest assured, today’s cellphones and laptops are completely safe. The manufacturers have started using the exact same cells they were using in the exploding products. Hey, what’s that? That’s right, the exact same cells. The problem lies not with the cells, it lies with the way you treat ‘m. Treat ‘m nice and you won’t have a problem. That’s what this guide is about. Li-ion cells are only dangerous if you don’t use them the way you’re supposed to use them. Thanks to the lawsuits and the martian invasion a lot of money has been spent to find out what exactly turns a Li-ion cell in a terrorist cell and how to prevent that from happening. Preventive actions are what this article is about. If you are sitting next to a burning Li-ion cell, quit reading, get outside, call the fire department or your local emergency number (US: 911, AU:000, UK and most former colonies: 999 Most of Europe: 112) and tell them your name, location and don’t forget to mention the fact that there’s a lithium fire burning.

*3 How to prevent the creation of a terrorist cell*

This is the core of the information. The CIA, the NSA, the MI6, the Mossad and the KGB couldn’t figure this one out, but here is the only real and effective method to prevent terrorist cells: Treat every single one of ‘m nice and there won’t be no terrorist cells.

*3.1 During charging*
Don’t overcharge your cells, don’t charge ‘m too fast and don’t leave ‘m alone.

No overcharging: You should stop charging when the cell has reached 4.2 volts. Just about any Li-ion charger I have ever heard off shows you when your cells have reached 4.2 volts (some lower, that’s no problem unless you want absolute full capacity, some higher, those are dangerous and should be disposed off). Some flash a light, some turn on a green light, some wave a flag. Here’s the kicker: most cheap chargers don’t quit charging at that moment. Why? Poor engineering, that’s why. There’s no excuse in my opinion. It’s plain and simple poor engineering. More on chargers later on in this guide.
So you need to take your cells off the charger as soon as the green light goes on / he starts waving the flag. 15 – 20 minutes overcharging won’t kill your cells, you don’t need to put a three man watch on your charger and hysterically pull the cells out when the light turns green, but if the flag has been waving for half an hour and the cells are still in the charger you’re doing things wrong. You need to do this with all your cells; no matter whether you use a cheap or an expensive charger. Because you never know, that’s why.

Also, if you don’t have one, buy a multimeter. A cheap one is good enough if you don’t plan on becoming heavily involved with electronics. Check the voltage of your cells when they come off the charger. Here's a guide on using a multimeter if you don't know how. Above 4.2 volts? Get rid of the charger and the cell. Recycle them both, don’t just throw them in the bin with the regular trash. Think about your children who will live in the mess you’re creating.

No charging too fast: The dangerous charge current for a Li-ion cell is 2C or higher. This means 2 times the capacity of the cell in one hour. If your cell has a capacity of 2200 mAh 2C is 4400 mA or 4.4 A. This current should never, ever be exceeded, not even for a second. Safe charging is done around 1C. Less is not necessarily better; Li-ion cells like to be exercised a bit during charging. Charging too slow won’t hurt the cell, but it will reduce the capacity faster over time.
If your cells are being charged too fast they will get hot to the touch. It’s normal for your cells to get warm during charging, but not hot. I think you know the difference between warm and hot. When a cell reaches 120°C it has officially become a terrorist cell and there is nothing you can do about it. Luckily, us mere humans can’t touch anything hotter than 60°C without serious discomfort, so as long as you can touch your cells you don’t need to run like hell. However, you do need to quit charging them in that charger if they feel hot, even when you can comfortably touch them.

Don’t leave ‘m alone: There is a bit of discussion about this one. Some people say you should never leave charging Li-ion cells alone, not even to go to the bathroom or answer the door. In my opinion, when you are charging one or two protected Li-ion cells in a decent charger that is overreacting. (More about decent chargers and protected cells later) You can leave your charging cells alone for 15 minutes maximum, not longer. After 15 minutes you need to check on your charging cells: are they hot to the touch, do they smell funny, is the green light on? Any of these means you need to quit charging. If you’re charging packs of multiple cells for RC vehicles, hotwires etc. you need to do your own research and decide what you think is the fine line between cautious and overcautious behaviour.

Let me also add this here: Li-ion cells should be charged on a fireproof surface. Don’t charge ‘m on a wooden table, don’t charge ‘m on paper, on a sofa, on a chair … Even if your cells don’t “vent with flame”, the charger and the cells can still get pretty hot (which usually means something is wrong), so don’t leave ‘m on a surface that can start a fire.

*3.2 During discharging*
Don’t over discharge, don’t discharge too fast, don’t leave ‘m alone. Sounds familiar, doesn’t it? That’s the reason this section is shorter than the “charging” section.

No over discharging: Li-ion cells should not be discharged below 3.0 volts. Take that multimeter you used after charging and check your cells when they’re discharged. Below 3.0 volts means you over discharged them. Be careful it doesn’t happen again. If the cell is discharged below 2.9 volts, recycle it. Discharging your cells too deep is not very dangerous in itself, but it is not safe to recharge them again. To prevent this from happening, quit using the same cell when your light gets noticeably dimmer (carry spare cells / lights if necessary) and recharge your cells often. Li-ion cells can be recharged without any problems even if discharged only a little bit so you can charge your cells when you know you've used them a bit and you will have full runtime again. 

No discharging too fast: The li-ion cells we’re talking about in this guide should never be discharged faster than 2C. A proper Li-ion compatible LED flashlight won’t discharge the correct cell too fast, so this should not be a problem.

Don’t leave ‘m alone: Make sure you are there to turn the light off if it gets too hot. If a hissing sound comes out of it or it starts to smell funny you have a terrorist cell in a (probably) metal container in your hand. Throw it somewhere it won’t hurt anybody when it explodes IMMEDIATELY. This is a thing which will not happen if you use proper cells and treat ‘m well, but I’m mentioning it just in case.

*3.3 The cells themselves*
Let’s do some good old racial profiling. The cells most likely to turn into terrorist cells are cheap Chinese cells. The cells least likely to turn into terrorist cells are expensive Chinese cells. Gee, maybe race hasn’t got anything at all to do with it?

Only buy name brand cells. Be a snob. It’s for your own safety. AW sells Li-ion cells here in the CPFmarketplace and his cells are generally regarded to be the best cells you can get because they have the best protective measures. Other decent brands include, but are not limited to: Sony, Sanyo and Panasonic. I used to include some low-end Chinese cells here, but the more I read and try out myself, the more I become convinced that there is no point in trying to save money by buying low-end Chinese protected cells. The price difference with high-end cells is not that big and the low-end cell's performance and safety is always worse. If you have cells from a different brand, check their reputation here on CPF or on RC forums or with other people who use Li-ion cells extensively. Do not trust the reviews on the sites you buy them from. The seller can add or remove reviews at his own will and anybody who can use a computer can call himself an expert reviewer.

Only buy protected cells. Protection circuits are a last measure to prevent your cells from turning into terrorist cells. A protection circuit will prevent current from flowing when a cell is being overcharged, charged too fast, over discharged, discharged too fast or gets too hot. This is a last measure. Don’t discharge until the protection circuit kicks in; don’t charge until the protection circuit kicks in. That’s dangerous behaviour. Protection circuits are designed and fabricated by humans, so they can never be 100% flawless, just like us mere humans. When you’re treating a protected cell properly two things have to fail before a serious accident occurs: you and the protection circuit. When you rely on the protection circuit to tell you when to quit charging / discharging, only one thing needs to fail for things to go seriously wrong.
If you want to use non-protected cells for any reason at all you need to do your own research and determine what safe and unsafe behaviour is. Some lights cannot use protected Li-ion cells because there are no protected Li-ion cells that fit them. Don’t buy those lights unless you are certain you know enough about the cells, the charger and the light you’re planning on using to avoid dangerous situations.

*4 Cells: Sizes, numbers, names, compatibility, confusion*

Size and voltage are the two main factors which determine whether any given cell can be used in any given light. Both size and voltage have to be right, it’s not because the cell will fit that it will work without ruining your light, your cells, your hand, your environment or any possible combination of these four.

*4.1 Size:*
Let’s be honest: size matters. Your cells have to physically fit in your light or they won’t be compatible, that’s for sure. Li-ion cells are named by using a numerical code which determines the size. The first pair of numbers is the diameter in millimetres, the second pair of numbers is the length in millimetres. 18650 cells have a diameter of 18 mm and a length of 65 mm. The last zero means it's a cylindrical cell.

These are some common Li-ion sizes:
14500: The size of a AA cell.
10440: The size of a AAA cell. Never protected. Do not use these without further research.
16340 AKA RCR123: The size of one CR123 cell.
17670: The size of two stacked CR123 cells.
17500: The size of one and a half stacked CR123 cells.
18650: These are the cells used in laptop battery packs. That’s why this size cells is most researched and most developed and these have the biggest capacity / volume ratio.

*4.2 Voltage*
The Li-ion cells we’re talking about in this guide deliver on average 3.7 volts under load and can deliver as much as 4.2 volts fresh off the charger. No primary cells do this, so most lights not designed to function with Li-ion cells can’t handle them without problems.
Recently most manufacturers have started advertising Li-ion compatibility because they realise it is a plus. If you’re not sure your light can handle Li-ion cells safely, either ask the manufacturer, search on CPF or try it yourself. The last option might kill your light / cell and it won’t be my fault and you won’t be able to sue me over it.

So, you cannot use RCR123’s in every light you can use CR123’s in. Surefire in particular doesn’t like rechargeable Li-ion cells because they make a lot of profit by selling their own top of the line primary CR123 cells, so most Surefire lights do not work very well with Li-ion cells. There are proven-to-work combinations, search here on CPF if you want to know which ones. Especially lights designed for 3 CR123 cells can often be used with 2 17500 cells. 2 17500 cells in series deliver 7.4 volts under load, which is pretty close to what 3 CR123 cells deliver under load. Do your own research about the light you're considering, it will not work in some lights.

*5 Chargers*

As I said before, most cheap chargers do not quit charging by themselves. The following cheap chargers are proven to quit charging by themselves:

Xtar wp6 - The best cheap charger if you're using 18650's IMO. Has a better charging algorithm than the following two chargers, but not yet perfect.

DSD charger – charges pretty slow and often only to 4.10 volts, but won’t overcharge. <=== Watch out with this one, I have received 2 defective chargers in a row, one did not charge at all, one kept charging in constant current mode which overcharged my cells pretty badly. When the charger is plugged in without a cell, the LED should be flashing red-green-red-green, when the cell is in the charger it should be either constant red (when charging) or constant green (when done charging). If the LED is not flashing when the charger is plugged in without a cell inserted you have a defective charger.

WF-139 charger – The old version of this charger had a trickle charge once the green light is on. The new charger apparently doesn’t; but beware, especially when ordering from cheap Chinese sites it is possible that you get old stock and your charger does overcharge. This charger also does not have the best charging algorithm, meaning it will shorten the life of your cells. Not dangerous in itself, but not good either.

The Pila IBC charger is regarded to be the safest and most reliable plug-and-play charger. It’s more expensive, but it’s the best and safest you can get without buying a hobby charger, like the guys flying remote controlled planes use..

Using one of these chargers is no excuse to leave your cells on the charger or leave your cells unattended for prolonged periods. Always take the cells off the charger when the green light comes on.

*6 Further reading*

Rechargeables & Flashlights
MD's Rechargeable Compatibility chart / guide for popular flashlights: Lists the most common rechargeable chemistries used and has a list of popular flashlights and their known rechargeable configurations.
MDs Lithium-Ion > Incandescent guide + compatibility / comparison chart: Basically the incandescent version of this guide, with a list of possible configurations. This guide was my inspiration for creating my guide. It's a great guide, but aimed at incandescent lights and some things do not count for LED flashlights.

Li-ion cell chemistry and safety measures
Lithium Ion Categories: A list of the most common Lithium-Ion chemistries with their important characteristics explained.
Photos of Protected Lithium Batteries: A thread in which you can see the protection circuit being removed from a Li-ion cell. Good to illustrate the difference between protected and unprotected cells.
Li-ion protection technology and possible dangers: A thread about the different types safety measures in Li-ion cells and how they work. Lots of information, but a lot of work to read it all.
Lithium Battery Safety Guide: A PDF file which contains a lot of safety information about how to treat both primary and rechargeable lithium cells, especially when they're leaking / venting with flame / playing terrorist cell. It's aimed at seafarers, but the information applies to lithium cells anywhere.


A big thank you to everybody who has helped me make this guide. Battery university, various CPF members who did a lot of research and gathered the information I combined and corrected my work, scientists, engineers ... And off course flashlight manufacturers. We all love them, and sometimes hate them. I guess that's it for now. Enyoy your light.


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## Black Rose

Nice job :thumbsup:

Personally, I'd remove Ultrafire from section 3.3.

Regarding the note about cells being above 4.2v. 
A good general rule, but it has been noted by some of the resident Li-Ion experts that 4.2v +/- 0.05v is acceptable. 
That measurement is also highly dependant on the accuracy of the DMM being used.


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## ARA

Gr8 work, just what i needed. :twothumbs

I just got a Olight M20 warrior premium along with trustfire RCR123s


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## Benson

Great guide!:thumbsup:

A couple thoughts:


JBorneu said:


> Only buy name brand cells. Be a snob. It’s for your own safety. AW sells Li-ion cells here in the CPFmarketplace and his cells are generally regarded to be the best cells you can get. They have the highest capacity and the best protective measures. Other decent brands include, but are not limited to: Sony, Sanyo, Panasonic and Ultrafire


AW's _aren't_ the highest capacity. The reason they're such a favorite is the rock-solid protection, consistent quality, and customer service, but the capacity is nothing special. Now that AW introduced 2.6Ah 18650s, the capacity isn't really lagging _behind_ (they used to be only 2.2Ah), but you can get 3Ah cells that deliver substantially better capacity at low discharge rates. As with any battery type, the highest capacity always comes at a cost -- they're totally unsuitable for moderate to high discharge, so the 2.6Ah or so are usually a better pick anyway.



> These are some common Li-ion sizes:
> 14500: The size of a AA cell.
> 10440: The size of a AAA cell. Never protected. Do not use these without further research.
> 16340 AKA RCR123: The size of one CR123 cell.
> 17670: The size of two stacked CR123 cells.
> 18650: These are the cells used in laptop battery packs. That’s why this size cells is most researched and most developed and these have the biggest capacity / volume ratio.


One other useful size you might want to mention was the 17500s; they're 1.5 CR123 cells, so you can stack 2 of them in a 3xCR123 light.



> *4.2 Voltage*
> The Li-ion cells we’re talking about in this guide deliver on average 3.7 volts under load and can deliver as much as 4.2 volts fresh off the charger. No primary cells do this, so most lights not designed to function with Li-ion cells can’t handle them without problems.


And that's where the 17500s shine -- 2 17500s at 4.2V starts at 8.4V, whereas 3 primaries @ 3V each start with 9V. Since the Li-ion hold up better under load, they work out great in most such applications.


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## JBorneu

Black Rose said:


> Nice job :thumbsup:
> 
> Personally, I'd remove Ultrafire from section 3.3.
> 
> Regarding the note about cells being above 4.2v.
> A good general rule, but it has been noted by some of the resident Li-Ion experts that 4.2v +/- 0.05v is acceptable.
> That measurement is also highly dependant on the accuracy of the DMM being used.



About the Ultrafire cells: They have less capacity and perform worse than the more expensive brands, but as far as I know protected ultrafire cells are also safe cells. If they are not, I will remove it. Maybe I should add a note about the performance, but if they're not dangerous I don't think they should be removed.

The safe charging voltage is an issue indeed. Especially the accuracy of the multimeter is a problem here. You need a very expensive multimeter to have sufficient accuracy, I'm not really sure how I should put it so I picked the most cautious way for now.


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## JBorneu

After a bit more research, I decided to remove Ultrafire after all.


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## dal205

Thanks for the info. I'm a newbie when it comes to batteries and li-ion. You mention "Less is not necessarily better; Li-ion cells like to be exercised a bit during charging. Charging too slow won’t hurt the cell, but it will reduce the capacity faster over time." Can you quantify "too slow" and how much capacity will decrease over time? I'm working on an application that scavenges energy using a thermo-electric converter. I'd like to charge a li-ion battery during down time so that I can power the device even when the TE isn't providing any power. The only issue is I have very little current available for charging. A couple of mA at best. I realize I cannot fully charge the battery, but that's OK. I only need 3.6V max to run my app. In fact, I want to keep my battery voltage between 3.3V and 3.6V. Is it possible to charge an li-ion battery with only a couple of mA?


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## JBorneu

dal205: I honestly don't know enough to answer your question very well. The ideal charging current is often quoted as somewhere around 0.7C. Slower charging sure is possible, but I cannot specifically tell you how much faster the capacity of a Li-ion cell will be reduced on a slow charge.

Do your own research about rechargeable cells while keeping your application in mind. From the voltage range you specified I would consider 3 NiMH / Nicad cells in series rather than one Li-ion cell though. But this is off topic, if you want to you can ask the battery experts of CPF for advice in the general battery forum or send them a PM.


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## DHart

Nice summary... a must read for any li-ion newbie! You might want to include some links to the other li-ion primers on this forum for newbies to easily follow for more in depth info.

As for cell size nomenclature, I believe the "O" at the end indicates a round cell body.


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## foo.spam

If you don't mind me asking, why did you remove the Ultrafires?

You stated "but as far as I know protected ultrafire cells are also safe cells. If they are not, I will remove it" - so did you find any indication that they are unsafe?

I ask because me being a Li-Ion n00b bought Ultrafire 3AH from BJ for my Legion II... and I havn't found any info indicating that they are unsafe. But then I havn't looked for it either.

tom


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## foo.spam

"note to self" ....

I just finished the 1st duty cycle on the Ultrafire 3AHs, and as the light shut down two of the batteries read 3.20V, and the last read 0.01V on my Fluke 87. I haven't tried recharging it yet - don't know if it's "safe" so I'll do it outdoors tomorrow.

Hmm.... I think I will consider another brand next time....?


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## xenonk

He probably figured the odds of getting a cell with defective protection are high enough to remove UF from the running, as their QC isn't top notch.

~0 volts sounds like the protection circuit just tripped like it's supposed to, but you can never be too careful.


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## foo.spam

wrt protection, what kind of protection is common in such batteries?

- overvoltage?
- undervoltage?
- charge current?
- discharge current?
- temperature?

Just before the light turned off (with 1 of 3 batteries at 0V) the light gave off 2 fast blinks every 6 or 7 seconds for s minute. Could this be the protection circuit? Is that common? (I don't know yet if the light has low-volt warning).

Is the protection on Li-Ion batteries usually something that can be "reset" by putting them in a charger, or is it a "trip once and throw away the battery" ?

t


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## xenonk

I suspect the two blink cycle is the Legion II's low battery warning. Kicking a cell in and out of protection wouldn't be that consistent.

Discharge protection should reset when put into a charger. The cell doesn't die, though you generally want to avoid discharging a cell so far that the protection trips because it's not healthy for it to have the voltage drop that low.

Cheap protected batteries will have over/under-voltage protection, and usually discharge current which doubles as short circuit protection. They pretty much never have charge current, reverse polarity or thermal protection.


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## JBorneu

foo.spam: I removed the Ultrafire cells for two reasons:
1) They have less performance and the chances of getting a cell with a bad component (including but not limited to a bad protection circuit) are higher due to (the lack of) quality control the cheap Chinese way.

2) If the cells are dropped hard the protection circuit can get damaged and can short-circuit the battery. The metal wire you see on the side of a protected cell under the outer wrapping connects the positive side to the protection circuit which is connected to the negative side. This connection can short the cell if it gets dropped (hard - very hard) and the PCP breaks. This is something which can happen with any protected cell. However, quality cells should not explode violently / catch fire even if they are shorted. Instead the cell will vent slowly, leaking it's contents without catching fire / exploding. The cell will be ruined, the light might be ruined, but your hand will be safe. These safety vents are also present in most cheaper cells (the two holes on the positive nub), but the chances of them not working properly are much higher.

Here is a thread where AW cells were compressed too much when tightening the tailcap (in a DIY mod, this will not happen in a production light). Luckily, it were quality cells, so nobody got hurt.

Here is a thread where protected cells are taken apart to show what makes 'em work. In it, AW confirms his current cells have an improved layer of isolation to reduce the chances of shorts occuring when the cells are dropped / crushed in another way (one of the reasons why his cells are considered to be the safest).

A flashlight is an illumination tool and it will be dropped, so the light and the cells in it should be able to survive hard drops. Protected Ultrafire cells, altough they are one of the best brands of cheap cells, are in my opinion not safe enough to withstand the abuse a user light will go trough.

My advice to you: Don't obsess over it. Enjoy your light and your cells. But next time you buy cells for your $200 light, don't try to cut costs by using cheap cells. The Ultrafire cells are safe as long as you treat 'em very well, but know that they can't be abused, under no circumstances. Don't panick if you drop the light, but check the cells when you do. If they are hot or leaking, throw 'em somewhere they can't hurt anybody (and wash your hands very well and don't breathe the fumes). And make sure your dog / child doesn't go fetch them. If you're using your light for law enforcement / emergency services however, buy better cells. Use the Ultrafire cells when showing off to your neighbours and use quality cells when working.

By the way, in a high-drain light like the Neofab Legion II the Ultrafire 3000 Mah cells last less long than better cells with lower capacity. The 3000 Mah rating is only true for slow drains, higher quality cell will have a higher true capacity at high discharge currents, meaning your light will run longer.


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## neoseikan

I have a friend who produce Li-on cells.
He has different cells available, from 2000mAh to 2400mAh, but his customers will use "Ultrafire 3000mAh" labels in them.
So, I guess the real capacity of your cells might be a bit lower.
He told me that his 2200mAh cells are the best, so I ordered a lot for testing lights.

Yours, Neoseikan



JBorneu said:


> foo.spam: I removed the Ultrafire cells for two reasons:
> 1) They have less performance and the chances of getting a cell with a bad component (including but not limited to a bad protection circuit) are higher due to (the lack of) quality control the cheap Chinese way.
> 
> 2) If the cells are dropped hard the protection circuit can get damaged and can short-circuit the battery. The metal wire you see on the side of a protected cell under the outer wrapping connects the positive side to the protection circuit which is connected to the negative side. This connection can short the cell if it gets dropped (hard - very hard) and the PCP breaks. This is something which can happen with any protected cell. However, quality cells should not explode violently / catch fire even if they are shorted. Instead the cell will vent slowly, leaking it's contents without catching fire / exploding. The cell will be ruined, the light might be ruined, but your hand will be safe. These safety vents are also present in most cheaper cells (the two holes on the positive nub), but the chances of them not working properly are much higher.
> 
> Here is a thread where AW cells were compressed too much when tightening the tailcap (in a DIY mod, this will not happen in a production light). Luckily, it were quality cells, so nobody got hurt.
> 
> Here is a thread where protected cells are taken apart to show what makes 'em work. In it, AW confirms his current cells have an improved layer of isolation to reduce the chances of shorts occuring when the cells are dropped / crushed in another way (one of the reasons why his cells are considered to be the safest).
> 
> A flashlight is an illumination tool and it will be dropped, so the light and the cells in it should be able to survive hard drops. Protected Ultrafire cells, altough they are one of the best brands of cheap cells, are in my opinion not safe enough to withstand the abuse a user light will go trough.
> 
> My advice to you: Don't obsess over it. Enjoy your light and your cells. But next time you buy cells for your $200 light, don't try to cut costs by using cheap cells. The Ultrafire cells are safe as long as you treat 'em very well, but know that they can't be abused, under no circumstances. Don't panick if you drop the light, but check the cells when you do. If they are hot or leaking, throw 'em somewhere they can't hurt anybody (and wash your hands very well and don't breathe the fumes). And make sure your dog / child doesn't go fetch them. If you're using your light for law enforcement / emergency services however, buy better cells. Use the Ultrafire cells when showing off to your neighbours and use quality cells when working.
> 
> By the way, in a high-drain light like the Neofab Legion II the Ultrafire 3000 Mah cells last less long than better cells with lower capacity. The 3000 Mah rating is only true for slow drains, higher quality cell will have a higher true capacity at high discharge currents, meaning your light will run longer.


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## foo.spam

Hmmm..... you learn as long as you live 

I just bought them from BJ because they seemed to be high capacity...

The Legion II definitivly deserves good batteries so I'll look into the AW's, and order some.

Thank you all!

-t


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## xenonk

The findings on the 3000mah UF cells are here, by the way:
https://www.candlepowerforums.com/posts/2884072


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## DM51

It is a great pity that people continue to ignore the overwhelming number of threads and posts there have been on CPF about the extremely poor quality of Ultrafire cells.


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## HighLumens

Thanks for this guide!!


----------



## neoseikan

One day I just put two brand new 18650s into a brand new charger, they got hot immediately,
So, I thought the charger caused short. But when I check the charger with multimeter, I found the +/- poles are not connected. Quite strange.


----------



## broadwayblue

JBorneu said:


> Ahoy there
> 
> 10440: The size of a AAA cell. Never protected. Do not use these without further research.



I've been using these for a year now. Bought them from AW for my Liteflux LF2. Should I be worried about them exploding in my pocket???


----------



## DHart

broadwayblue said:


> I've been using these for a year now. Bought them from AW for my Liteflux LF2. Should I be worried about them exploding in my pocket???



If you monitor the cells closely to make sure they are not over discharged nor over charged and you should be fine. I use them exclusively in my LD01s, LF2XT, and K-103.


----------



## JBorneu

broadwayblue said:


> I've been using these for a year now. Bought them from AW for my Liteflux LF2. Should I be worried about them exploding in my pocket???



The Liteflux LF2 (and it's newer variants) is one of the very few AAA lights with overdischarge protection and full Li-ion support. Program it so the overdischarge protection is on, do not use maximum mode for any extended ammount of time and recharge your cells often if you use it a lot. I EDC an LF2X running on a li-ion cell myself, nothing to worry about if you're careful and responsible (and you're using AW cells in a light made to be run on Li-ions and you read this thread so in all probability you are). The main danger is the light getting too hot on maximum mode. I programmed mine so the 2 stages are set on lowest low and as bright as possible without any heating of the light. That way, if it comes on in my pocket, even it it gets twisted all the way to P2, it won't get too hot. The user-adjustable mode is set to maximum, so if I want to show off, it's just a quick 2-switch away.

In my personal opinion, it's not a good idea to run the Fenix LD01 or the Akoray K-103 on 10440's. There are a number of threads discussing this so I won't go any further than saying that in the context of this thread (newbies and Li-ions) I will not recommend it to anyone.


----------



## eljuez

Very useful post. Thanks.:thumbsup:


----------



## LuxLuthor

-----


----------



## Brasso

I recently purchased an AW10500 protected cell and a WF-139 charger from Lighthound. Is there anything particular that I need to be worried about with this setup?


----------



## JBorneu

Brasso said:


> I recently purchased an AW10500 protected cell and a WF-139 charger from Lighthound. Is there anything particular that I need to be worried about with this setup?



I can't find a 10500 cell on lighthound and I have never heard of it before. Do you mean a 14500 (AA size) cell? If so, make sure nobody puts it in anything designed only for regular 1.5 volt AA cells (children, spouse etc.). Other than that, no.


----------



## Brasso

Sorry, typo. Meant 18500.


----------



## Vesper

So when I use my 2x18500's in a light until it cuts out, this is the protection circuit kicking in, right? If so, is this bad practice? My light (in this case a MC-E) doesn't dim, just drops below voltage and turns off.


----------



## DM51

It's best to recharge Li-Ions well before they reach the low cut-out. In fact, you can recharge them as often as you like - it's much better for them than running them down to empty.


----------



## tsmith35

I put my charger in a metal bucket in the center of the garage (away from other stuff) while charging. If trouble occurs, I can open the door and carry the bucket out. Inexpensive and effective.


----------



## CDP930

Hey guys

I've been reading and researching this "end" of the light market for a while. I plan on getting my Z2 bored out, and hopefully a MD4. Anyway, all this reading I have doing about terrorist cells and treating cells right is starting to freak me out.

I'm a LEO and am looking at these lights for duty. ARE these types of lights suitable for rough use? From reading it seems like it would be the definition of not treating the cells right.

I guess the lights themselves are tough enough, but I'm kinda worried about my hand blowing up now.

Can someone put my mind at ease on this topic, please! I don't want to wait any longer to buy my new toys...I mean tools.

Thanks in advance


----------



## tsmith35

I think all of the stories I've heard about cells blowing up end up being due to any of these: primary CR123 cells that are shorted out or overheated, multiple primary cells mismatched (different ages/voltages), use of non-name-brand primary cells, dropping bare cells onto hard surfaces, and attempting to charge primary/non-rechargeable cells.

Personally, I stick with alkalines, NiMH (either low-self-discharge like Eneloops or normal NiMH if I don't need long term charge-holding), or protected AW lithium ion rechargeables. I don't worry about using primary CR123 cells in single-cell lights. I treat my lithiums with care and keep them in a case (to avoid shorts & damage) if I need to carry them as spares.


----------



## CDP930

So dropping them is a no no? I assume that also applies while they cells are in the light? What I carry will be dropped at some point, so should I reconsider these types of batteries?

I am completely new to these kind of set-ups, a big Streamlight person just due to the commonality factor. However seeing the numbers on some of these units completely amazes me, and want to carry something powered by 18650.


----------



## tsmith35

CDP930 said:


> So dropping them is a no no? I assume that also applies while they cells are in the light? What I carry will be dropped at some point, so should I reconsider these types of batteries?



Dropping bare cells is not good, but the flashlight will absorb most of the shock and prevent the batteries from suffering any physical damage. I don't recall any stories of battery damage occurring from dropped flashlights. US-made cells with the UL label should be fine, but the cardinal rule of lithium primary batteries is to replace all batteries at the same time with new batteries of the same brand, capacity and state-of-charge (voltage level, for all practical purposes). As long as you replace all cells at the same time and pull all new cells out of the same package of US-made/UL-labeled cells, you should be fine.

There are millions of folks using lithium primary cells in flashlights, but relatively few reports of exploding batteries. Most exploding batteries I've heard about end up being due to mixing old/new cells or cells of different brand/size/capacity/state-of-charge. Follow the basic rules for lithium primaries and you shouldn't have any problem.

There's a nice article covering this info here.

FWIW, you'll enjoy the additional runtime and brightness afforded you by lithium cells. Lots of power in a small package.


----------



## Benson

CDP930 said:


> I'm a LEO and am looking at these lights for duty. ARE these types of lights suitable for rough use?


In an appropriate light, and with appropriate chargers, yes.


> From reading it seems like it would be the definition of not treating the cells right.


Not really -- physical damage to the cells _is_ one form of not treating them right, but the only way that happens using them in a light is if the light itself is structurally compromised. (e.g. If you use a thin-wall light as a prybar, then when it collapses, it crushes the cells inside and could cause a short.) The most prevalent forms of abuse are all _electrical_ in nature -- overdischarge, overcurrent, and overcharge, and how roughly you need to use your lights in the field has nothing to do with them.

tsmith35: I think he's considering Li-ions, not metallic lithium primaries; the typical failure modes are rather different.


----------



## JBorneu

CDP930: In a bored out Surefire Z2 you shouldn't worry about damage to the cell when you drop it, as long as you don't drop it off a skyscraper. The cell is suspended between two springs which absorb most of the shock. Make sure you use AW cells and a quality charger (the Pila IBC charger is the best plug and play charger). AW's cells are the only protected cells (that I know off) which are designed specifically to avoid an accidental short if the cell gets dropped and the protection circuit breaks, so if you drop the bare cell and the protection circuit breaks it still won't explode, but it might vent and it won't work anymore.


----------



## CDP930

Thanks so much for the help. I can't wait to get all my goodies. 

Out of curiosity, does anyone own a Surefire mod? I know there have been beamshot comparisons done, but what's a M30 or 60 like compared to, oh say a Fenix P3D or a Pelican 7060? I'm don't have any hands on time with any of these super bright lights as I bought lights more common in the field simply because everyone carried them. However, I am excited to say I'm ready to break the mold.


----------



## tsmith35

Benson said:


> tsmith35: I think he's considering Li-ions, not metallic lithium primaries; the typical failure modes are rather different.



Oops, yep. I missed the part about "18650". I kept thinking of stock SF lights.


----------



## gmf2010

I'm sorry if I missed this somewhere, but what is the best way to store Li-Ons that aren't being used?

I just purchased 2 AW14500s, a WF-139 charger, and a Nitecore NDI R2 for EDC.

I intend to keep one cell in the light and the other charged, at home, for a spare.

What is the best way to store the charged spare?

Also, if this isn't straying from the topic too much, I also have a box of CR123 batteries sitting in my desk drawer. Should I be storing these someplace else, like my refrigerator?

Thanks so much.


----------



## gmf2010

I found this post: https://www.candlepowerforums.com/threads/97484, which answered most of my questions.

Please feel free to add anything if you'd like =)


----------



## garden

Mate, I think you've got yourself a bit too hypo about battery safety. I will admit I am not an expert on chemistry or batteries but the possibility of a li - ion battery exploding or firing up is probably the same as winning the lottery. For the battery to explode, it needs to reach some extreme temperature. The autoignition ( set on fire by heat alone, no fire no spark) for li -ion is probably somewhere around 500 degrees C. For 3.7 volts to do that in a short circuit, the short circuted battery needs to somehow destroy the ac dc adaptor and a 240 v current would be needed to create a fire. However the chance of this happening is low and most houses have a main switchboard that would switch off the mains electricity upon short circuit. 



So overall I'm saying that the chances of fire from overcharging is very unlikely


----------



## SilverFox

Hello Garden,

Welcome to CPF.

The reason for the emphasis on safety comes from the way we are using these cells. In a laptop or phone, we take great care not to drop or damage them. With a flashlight, it is easy to drop a cell, or the whole light, or sometimes you run the cell into an over discharged condition.

Most of us are not in the proximity of extreme heat, but if a cell suffers internal damage it can short out internally. Also, over discharging causes metal lithium to plate out within the cell. This metal is extremely unstable.

Now we have a situation where the next charge could cause a local problem where temperatures could get out of control resulting in rapid venting with flame. Since this initiates on a micro level within the cell, the household circuit breakers offer no protection at all.

The potential energy of this chemistry is high, so it is prudent to ramp up the safety measures when using or charging these cells.

Tom


----------



## Magic Matt

I don't mean to be rude here, but surely there must be some massive errors in that information. If the chargers and batteries were anything like as dangerous as they are being made to sound, then they wouldn't even be allowed to go on sale in the UK. As it happens, I sit here with a laptop that has a battery with a whole bank of cells which take a hammering in terms of charging in the laptop and physical journeys in backpacks and bags. The warning make it sound as if I'm holding a stick of lit dynamite.

With my laptop, charging its bank of Li-ion cells, it is frequently left on charge overnight on the desk and I know of hundreds of people that leave their laptops on charge from a Friday afternoon until a Monday morning.

Most people charge their mobile phones overnight and don't worry about them blowing up. We carry them in our pocket the same way we would do a wallet, and you could argue a mobile phone is far more likely to short out internally from being in a wet coat than a torch would. 

If you buy cheap cells from a country that doesn't have the same rules and regulations as far as safety standards go, then you need to take extra precautions... of course that goes for a lot more than just Li-ion cells. Any cells on sale in the UK have to confirm to fairly strict safety standards by law and it's illegal for a UK retailer to sell any that don't - as far as I know the US is the same, but feel free to correct me if I'm wrong. I believe the current standards insist on a fairly high degree of impact resistance as well as protection from over charging and over discharging.

If you bought a good charger conforming to the safety standards required, and cells to match, there's no reason you should be worried using them in off-the-shelf products that are designed to take them.

If you're going to start messing around putting components together that aren't designed to be used that way, then you need to take every precaution possible.

If we're talking about making our own circuits and modding torches, then yes we should take a lot of extra precautions, test everything, test it again, and then just to be safe, test it some more.


----------



## tsmith35

The only real danger when comparing loose cells vs. battery packs really boils down to a few things:

Loose cells have a relatively large amount of terminal surface area exposed, increasing the possibility of accidental contact/shorting.
Battery packs have a relatively small amount of terminal surface area exposed, and generally have some form of electronic protection between the terminal surfaces and the actual battery terminals.

Loose cells generally have no protective container on them.
Battery packs generally provide a protective container to help protect the internal cells.

Loose cells are easily handled badly. They roll off tables, get dropped in trash cans, get dropped into boxes.
Battery packs are generally handled as well as the object that it is powering: laptops, cell phones, cameras, etc. They're treated better.

Loose cells generally have no protection circuitry.
Battery packs are generally protected by electronic circuitry designed to prevent overheating, overcharging, under-voltage use, and shorting.

Loose cells may be called upon to provide high amperage levels.
Battery packs generally provide lower amperage levels and have regulation circuitry to prevent excessive current flow above a specified level.

Loose cells may be dropped into any halfway compatible charger in any orientation.
Battery packs must generally be plugged into a specific charger that provides a physically keyed charge polarity, current level, and voltage. Actual charging is regulated electronically by a device-specific circuit.

Exploding batteries are not normal. They're not an everyday occurrence. It likely won't happen to you. But ignoring the possibility of injury due to an exploding battery is foolish. Do you drive with a seatbelt on? Do you have a smoke alarm in your house? Have all family members been taught to dial 9-1-1 in an emergency? The possibility that your life will be saved by a seatbelt, that you'll ever need your smoke alarm, or that you'll ever have to dial 9-1-1 are all extremely remote. But it's generally thought that it's better to be safe than sorry.

Learn what lithium batteries are capable of. Learn how to handle them safely and what to do in case of a fire or explosion. And hope you never need to deal with it. Sure, you can stick your head in the sand and say, "It'll never happen to me". There's a good chance you'll be right.


----------



## SilverFox

Hello Magic Matt,

I am not sure how things are in the UK, but in the US you can't run down to the local store and buy a Li-Ion loose cell, and a charger to charge it.

The reason the local stores don't sell loose cells is because Li-Ion battery manufacturers won't sell them to them. Battery manufactures are even hesitant to send out samples for evaluation, unless you provide them with details on the battery pack construction and the safety measures you have in place to protect the cells from over charge, under charge, and physical damage.

Cell phones and laptops are engineered, designed, and have safeties to protect the battery pack. Loose cells in a flashlight are many steps below this, and thus the main battery manufacturers don't sell loose cells.

Even with all the safeties in place, you will recall that a few laptop battery packs ended up rapidly venting with flame.

Here is something you can do to verify all of this. Contact Sony, or Sanyo, or GP, or Panasonic, or LG, and tell them that you are interested in purchasing some loose cells for your flashlight, and see what kind of response you get...

The proper way to charge a Li-Ion cell is to use a CC/CV algorithm with the voltage limited to 4.20 volts (+ or - 0.05 volts) and have the current shut off when it drops below about 50 mA. If the cell voltage is below 3.0 volts, the charger should start off with a very low charge rate until the cell reaches a voltage of around 3.4 volts, then it can continue on with the CC phase. Another safety built into the charger is a timer. If the charge has not completed in the alloted time, the charge is terminated. There are a few other safety checks done to make sure the cell is OK to charge as well.

How many chargers available to the CPF community follow this charge method? Your cell phone does, as does your laptop. The Pila IBC charger comes close, but even it doesn't have all the safeties required for "safe" charging.

12 volt automobile batteries are generally considered safe as long as you take the proper precautions when handling them. However, if you have ever witnessed one explode, you would think twice about their safety. Fortunately this does not happen very often. I have witnessed this, and it was very sobering. I have also witnessed some 18650 cells rapidly vent with flame, and have a great respect for the energy contained within the cell.

The reason the battery manufactures don't sell individual cells for the local shops to pass on to you is because of these safety concerns, and liability. We understand these concerns and take them very seriously. We have taken the stance that education is the best way toward safety and try to explain the safe use of Li-Ion cells. 

When you use a piece of equipment that is well designed and has all the safeties built into its operation, you can plug it in and forget it. When you don't have this, you have to take safety into your own hands and act accordingly.

Tom


----------



## Magic Matt

I agree with most of your points, tsmith, but these I disagree in part with...



tsmith35 said:


> Loose cells generally have no protective container on them.
> Battery packs generally provide a protective container to help protect the internal cells.



The only cells I've seen have some sort of protection on them - usually a plastic vacuum wrap or similar, which is surprisingly resilient to scratching and moisture. No way near as touch as a solid casing, but I wouldn't class it as no protection at all.



tsmith35 said:


> Loose cells are easily handled badly. They roll off tables, get dropped in trash cans, get dropped into boxes.
> Battery packs are generally handled as well as the object that it is powering: laptops, cell phones, cameras, etc. They're treated better.



I totally disagree there. Having seen many battery packs abused to the point where they're scratched, scuffed, batterred etc. I would say most of my cells are handled better than my battery packs! I've certainly dropped my battery packs onto a concrete floor trying to change them in near blackness before, and not thought much of it (except to check for cracks).



tsmith35 said:


> Loose cells generally have no protection circuitry.
> Battery packs are generally protected by electronic circuitry designed to prevent overheating, overcharging, under-voltage use, and shorting.



I may be wrong, but I thought all Li-ion rechargable packs or cells had to have the circuitry before they were allowed to be sold in the UK. This may in part be why they're so hard to find.



tsmith35 said:


> Loose cells may be dropped into any halfway compatible charger in any orientation.
> Battery packs must generally be plugged into a specific charger that provides a physically keyed charge polarity, current level, and voltage. Actual charging is regulated electronically by a device-specific circuit.



A charger that has no reverse polarity protection, even on something as basic as a NiCd cell, shouldn't be used anyway IMHO. As far as I know, cells are usually keyed, and a good charger also takes avantage of that (I can't physically put my AA cells in the wrong way into my charger for example - they wont touch the contacts if I do).


----------



## Magic Matt

SilverFox said:


> Hello Magic Matt,
> 
> I am not sure how things are in the UK, but in the US you can't run down to the local store and buy a Li-Ion loose cell, and a charger to charge it.



I was going to post this... then looked again in shock as I realised it's not an RCR123, it's a CR123 and charger!!
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=5109376

(I should add I usually run screaming from anything branded Uniross - I'm not even convinced their NiMH chargers work that well).

You have to hunt around to find Li-ion chargers, but you can get them. I've not seen anything that takes or charges 18560 cells, only ever (R)CR123. I wish I had picked up the Panasonic RCR123 cells and charger when I saw them, but I wasn't as educated then as I am now - I've never seen it again since and had people tell me it doesn't exist - it could have been a CR123 charger I guess, but it was definately Panasonic and came with two cells.



SilverFox said:


> If the cell voltage is below 3.0 volts, the charger should start off with a very low charge rate until the cell reaches a voltage of around 3.4 volts, then it can continue on with the CC phase.



That surprises me - I didn't think you were supposed to charge them at all below 3.2V!

What we really need I guess, are universal Li-ion battery packs and chargers as opposed to loose cells.


----------



## Benson

Magic Matt said:


> I was going to post this... then looked again in shock as I realised it's not an RCR123, it's a CR123 and charger!!
> http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=5109376


"RCR123" is a conventional designation, but by no means standard. "CR123 rechargeable" means exactly the same thing.


----------



## Magic Matt

Benson said:


> "RCR123" is a conventional designation, but by no means standard. "CR123 rechargeable" means exactly the same thing.



Ahhh, thanks for clearing that up. 

Still, an off-the-shelf rechargable CR-123 with charger ... and they also sell spare cells ... part of me is curious to know how it stacks up against other chargers recommended on here. If RS sell it, then that means a high street retailer could stock it if there were a demand.


----------



## 45/70

Removed original content of this post.

Due to the distraction caused by "holiday cheer" (at least that's the excuse I'm giving ), I _somehow_:thinking: thought I was responding to another thread about RadioShaft RCR123 chargers.

Dave


----------



## rmteo

I'm wondering, since Matt is from the UK, if he was referring to RS Components - a British distributor of electronic components and the like, kinda like an equivalent to our Mouser, Digikey, etc.


----------



## 45/70

rmteo said:


> I'm wondering, since Matt is from the UK, if he was referring to RS Components - a British distributor of electronic components and the like, kinda like an equivalent to our Mouser, Digikey, etc.



Ah, after looking at Matt's link, I find you are correct rmteo. My apologies yet again! :candle:

And to be totally politically incorrect (I live in the U.S.)

Merry Christmas All! :santa:

Dave


----------



## LeifUK

There is a post on this site from someone who placed normal Lithium batteries in a charger and one exploded and vented toxic fumes. 

Anyway, I am surprised at the apparent danger of these Li-ion cells. The laptop batteries that caught fire were faulty, very few caught fire (relative to the number sold), and all affected units were recalled. 

Rechargeable Li-ion cells are used in cameras, many millions of which are sold each year, and in iPods and other devices. These are dropped routinely, and used by juveniles. I am unaware of any incidents from kosher units. (I have read posts from several photographers who bought cheap third party camera batteries and experienced fires. In one case the battery caught fire duing charging and the owner's house was partially burnt down.) 

According to the original post torch/flashlight cells are very dangerous. Surely no normal person would watch a charging cell, and check it every 15 minutes. It's madness. According to this thread torch/flashlight cells are unstable due to poorer safety measures. Why is that? Why not force them to adopt the same standards. It all seems weird. Sorry for my tone, but it does not make sense. 

The reason why they are so hard to obtain in the US is probably due to the litigeousnous of the country. After all you people can sue a company because they sell a cherry tart without a warning that it is hot. (I like to think that our judges would class the customer as a moron, and dismiss the case. I fear I am wrong. When you cough, we catch a cold.)


----------



## tsmith35

Magic Matt said:


> The only cells I've seen have some sort of protection on them - usually a plastic vacuum wrap or similar, which is surprisingly resilient to scratching and moisture. No way near as touch as a solid casing, but I wouldn't class it as no protection at all.



The shrink wrap doesn't provide much protection against physical damage, i.e., distortion of the cell case, like a battery pack's physical case would. It will protect against minor damage, but that's about it.



Magic Matt said:


> I totally disagree there. Having seen many battery packs abused to the point where they're scratched, scuffed, batterred etc. I would say most of my cells are handled better than my battery packs! I've certainly dropped my battery packs onto a concrete floor trying to change them in near blackness before, and not thought much of it (except to check for cracks).



But that's just it: the plastic case helps protect the cells from physical damage, whereas a bare cell may have a corner dented, end impacted, etc. If the impact doesn't crack/break the plastic case (and physically damage the cells), the cells are likely okay.



Magic Matt said:


> I may be wrong, but I thought all Li-ion rechargable packs or cells had to have the circuitry before they were allowed to be sold in the UK. This may in part be why they're so hard to find.



Packs, maybe. But individual cells probably don't have any protection unless specified.



Magic Matt said:


> A charger that has no reverse polarity protection, even on something as basic as a NiCd cell, shouldn't be used anyway IMHO. As far as I know, cells are usually keyed, and a good charger also takes avantage of that (I can't physically put my AA cells in the wrong way into my charger for example - they wont touch the contacts if I do).



A charger without reverse polarity protection shouldn't be used, but they are certainly available. Poke-yoke dictates that a charger shouldn't accept a cell backwards, but I own several chargers that will happily accept backwards cells. Bad design. Since I know the dangers of inserting cells backwards, I'm very attentive when I put batteries in my chargers. I'm sure the possibility of fire/explosion would be much greater if I didn't pay close attention.

Knowledgeable folks such as yourself and most others on the forums won't ever have problems with their lithium batteries. But most folks in the general public simply don't know any better, so it's worthwhile for all of us to caution friends and family as to how they should treat lithium rechargeables.

I know I have kept lithium batteries on-charge for years (literally) until I found out how dangerous that practice is. Now I plan ahead and charge my lithium cells/packs as needed to maintain a long cell life and provide a safer environment for me and my family. There's the possibility that I could have continued the practice of leaving lithiums plugged in for the rest of my life and suffered no ill consequences. But why chance it?


----------



## JBorneu

Hi all

I'm very busy at the moment, so I haven't been able to check CPF for a while. Looks like there has emerged a whole new discussion within this thread.

The thing is, folks, Li-ion cells can be very dangerous. That is an irrefutable fact. If you think li-ion cells cannot pose any danger, you don't know what you're talking about. It's that simple.

The key word here is "can". When lithium cells are treated the way they are supposed to be treated, they are not dangerous. That is why there are millions of consumer electronics which run on li-ion cells used daily without any accidents. The manufacturer designs a device and designs a battery pack to go with it. As long as the proper pattery pack is used in the proper device, the manufacturer controls every single step: the power source, the charging algorithm, the maximum charging voltage and current, the maximum discharge current, the overdischarge protection, the quality of the components, the various safety measures, the capacity and quality of the cells, the packaging ... Basically, he can make sure himself that every single component is a perfect match for the cells and the rest of the device, be it an MP3 player or a laptop. That is why he will sell you a li-ion battery pack for your laptop: because he knows he did everything right himself and nothing will go wrong as long as you don't tear the battery pack open and start playing with the individual cells and putting them in different chargers and making a charger out of a mobile phone / laptop / power supply / circuit of resistors (like a lot of people do here on CPF). Those are all things which can be done without accidents, but they all require a level of knowledge far above that of the regular consumer.

Now, when you start playing with loose cells, the manufacturer has no control whatsoever about the way the cells are used. He does not want the responsibility of selling loose li-ion cells to regular people who don't know what they are or how to use them, so he won't sell them at all. Remember, whe are putting loose cells in flashlights, often in series, often without protection circuitry, often draining the cells near or over their maximum rated current. This is "edgeplay", as you could call it: we are pushing the boundaries of safe behaviour. Having to carry responsibility for that is the nightmare of every battery manufacturer. That is the reason he only sells battery packs and not loose cells. People are stupid and careless, and he knows carelessness will cause serious accidents with li-ion cells. It WILL cause serious accidents. No "can" this time. Ignorance and carelessness go hand in hand (and expertism and carelessness sadly do too) and they don't mix with li-ion cells without catastrophical consequences.

My first post tells nothing but the truth. Li-ion cells are dangerous when used improperly but when you do what I write in the first post you will not have a problem. Remember people, the average IQ in the western civilization is 100. Everybody with any form of higher education (post high school) has at least 110-120. Most members of CPF have an IQ above 100. However, that means there is an equal number of people who have an IQ (sometimes far) below 100. Those people have an internet connection too, and most of them can read and use a credit card, which makes them capable of buying and mistreating li-ion cells. I sincerely hope my first post scares away everybody who is not intelligent enough to use li-ion cells in a safe manner. I think it does, and that is part of what it is intended to do. I'm not going to put a number on who is and who isn't intelligent enough because common sense is not measured in an IQ test so a 90 can have it while a 110 can lack it. When I consider all the kinds of people who can read this thread: child, elder, dumb, smart, male, female, factory worker, deskjob, tradesman, nanny ... I can tell myself honestly that any of these who follows my advice will not have an accident. Some people think they can be safe with less safety measures. If you think you can, feel free to do so, but it is entirely your own responsibility. I am not an expert, but I know for a fact that the advice in my first post is sound and will prevent accidents. And anybody who is heavily overwhelmed and scared away from li-ion cells by my first post shouldn't be using loose li-ion cells anyway.

I don't have the time right now to join the discussion about what is and what isn't safe with li-ion cells and packs etc, althoug it is a very valuable one, but now you know why I stand by my first post and will not lighten it.


----------



## 45/70

Just to add a bit to what JBorneu said (I'm not too sure about the IQ thing, I think folks with a higher IQ are more likely to stretch the limits, myself), here are two posts that I recently made in another thread, that deal with why loose Li-Ion cells can be a higher safety risk.

Dave


----------



## LeifUK

Quite frankly it sounds as if these things are not safe for sale to consumers, and I am surprised the companies can sell them to the general public. I'm not sure IQ comes into it. I know very clever people who are rather distracted, and would surely not last long with these cells. One aspect of clever people is the ability to pursue an idea and ignore distractions. Such as smoke from a nearby charger ....


----------



## DM51

LeifUK said:


> Quite frankly it sounds as if these things are not safe for sale to consumers, and I am surprised the companies can sell them to the general public. I'm not sure IQ comes into it. I know very clever people who are rather distracted, and would surely not last long with these cells. One aspect of clever people is the ability to pursue an idea and ignore distractions. Such as smoke from a nearby charger ....


LeifUK, please do some reading on the subject before making such lofty pronouncements. 

Li-Ion cells are not sold to "the general public" in the way you suggest - you can't just walk off the street into a store and buy loose Li-Ion cells.

They are only on sale to those who specifically look for them. It is completely unnecessary for people to be subjected to alarmist posts such as yours, claiming that they are dangerous. They are quite safe as long as you understand them and observe basic safety precautions.


----------



## LeifUK

DM51 said:


> LeifUK, please do some reading on the subject before making such lofty pronouncements.
> 
> Li-Ion cells are not sold to "the general public" in the way you suggest - you can't just walk off the street into a store and buy loose Li-Ion cells.
> 
> They are only on sale to those who specifically look for them. It is completely unnecessary for people to be subjected to alarmist posts such as yours, claiming that they are dangerous. They are quite safe as long as you understand them and observe basic safety precautions.



I'm sorry but my post is based on reading this thread. Are you telling me that the information here is wrong? If the information in this thread is correct, then it is my opinion that they are dangerous. 

As far as I know anyone can buy these cells online, whatever their age. Is that incorrect? If they go to a site that sells LED torches, chances are they will find that those using LiIon offer better performance. Hence they might want some. 

For example, in the first post it says "Don’t overcharge your cells, don’t charge ‘m too fast and don’t leave ‘m alone."

And "After 15 minutes you need to check on your charging cells"

So if I understand this correctly, this means that chargers do not come with safety mechanisms to prevent overcharging, or charging too fast. How many people would check them every 15 minutes? My guess would be no-one unless they had read this thread. And how many people would unknowingly charge too fast if they thought they could get cells charged more quickly? My guess is many people would unless they had read this thread. (Do the cells come with safety instructions? Do people read them? Usually not.) I suspect most people leave batteries charging overnight. I have LiIon cells for consumer goods such as cameras and iPods and as explained elsewhere, these are safe because the chargers are made properly with safety measures, as are the cells. 

The impression given by the first post is that these cells are unfit for sale to the general public. Of course you may disagree, but that is my opinion based on the information in this thread.


----------



## Benson

LeifUK said:


> I'm sorry but my post is based on reading this thread. Are you telling me that the information here is wrong? If the information in this thread is correct, then it is my opinion that they are dangerous.
> 
> As far as I know anyone can buy these cells online, whatever their age. Is that incorrect? If they go to a site that sells LED torches, chances are they will find that those using LiIon offer better performance. Hence they might want some.


Yes. Anyone can buy second-rate Li-ion cells, along with many other dangerous items, online. The world's a big place, and many parts of it have little regulation of product quality. They can also buy known reliable ones, but that'll usually cost a bit more, so don't bet on them doing it.



> For example, in the first post it says "Don’t overcharge your cells, don’t charge ‘m too fast and don’t leave ‘m alone."
> 
> And "After 15 minutes you need to check on your charging cells"
> 
> So if I understand this correctly, this means that chargers do not come with safety mechanisms to prevent overcharging, or charging too fast.


Generally, they do have such mechanisms -- but do you feel comfortable with a SPOF like that and no safety check? Most of the chargers in use are cheap stuff from HK deal sites which have a history of occasionally shipping shoddy merchandise, including some completely non-Li-ion-related items, which cause electrical fires. Many of the Li-ion cells available also fall into this category. If you use name-brand cells and chargers, your risk goes way down, and you could probably leave them alone and be as safe as the guy with cheapos, checking them every 15 minutes (unless he forgets); even with off-brand ones, once I've satisfied myself of their quality, and closely monitored a number of charging cycles, I slack off the monitoring considerably. But given the scarcity of completely reputable chargers and cells, it hardly makes sense to give advice based on that scenario.


----------



## LeifUK

Benson, that is very informative, and answers a lot of my questions. Out of interest, what are the name brands that are generally considered good quality? 

Maybe this is a stupid question but would it not be preferable to have a certification process whereby chargers and cells that cannot be left unattended cannot be sold? (I suppose that assumes that the problems are design issues, rather than ones of quality control, since a certification test would not test the latter. It also assumes that the process could be enforced across borders.)

By the way, what is 'SPOF'?


----------



## Max_Power

SPOF = Single Point Of Failure


----------



## Magic Matt

Without wishing to be too infamatory, I walked into a high street store today (specifically Soni Electronics of North End, Portsmouth) and they had rechargable CR123 cells on sale, with a charger. It was the same Uniross unit I saw at RS. I didn't buy it - it was very overpriced. I asked and they said they could easily get me other Li-ion cells within a few days if I told them the types I wanted (I was careful to tell them I wanted cells, not battery packs).

Soni Electronics typically sell various houshold stuff (bedside lights, spare plugs, fuses, TV aerials, watch batteries etc. etc.) and I would not class them as specialist.


----------



## Midnight Oil

Do some P60 drop-ins have a low-voltage protection mechanism that turns off the light to prevent the Li-Ion battery or batteries from over-discharging, while others that don't simply fall out of regulation, go into direct drive, and allow the battery or batteries to continue powering the light with dimming output?

Is getting a drop-in that has a low-voltage protection mechanism and using protected Li-Ion cells a substitute for monitoring the cell voltage with a multimeter, or should one always monitor the voltage, which means a lot of unscrewing the light, removing the batteries, and testing them?

Thanks.


----------



## Black Rose

Midnight Oil said:


> Do some P60 drop-ins have a low-voltage protection mechanism that turns off the light to prevent the Li-Ion battery or batteries from over-discharging,


I've read that some drop-ins will blink when the battery voltage gets low.

The ones I have purchased or received with lights did not.
I modified most of those with a driver that does have low-voltage protection built in.



> Is getting a drop-in that has a low-voltage protection mechanism and using protected Li-Ion cells a substitute for monitoring the cell voltage with a multimeter, or should one always monitor the voltage, which means a lot of unscrewing the light, removing the batteries, and testing them?


Using a drop-in that has low-voltage protection is a way to save the battery from being damaged, but no matter what, you should still monitor the cell voltages.

By doing so you will learn how your various drop-ins work with your batteries and you'll know when to charge your cells instead of ending up with no light and a possibly damaged battery. 

In the end, these protection circuits (baattery and driver circuit) are simply electronic devices that could fail.
Should the protection circuit fail, you are left to your own devices to determine when the light will go dark.

Li-Ion cells prefer to be topped up (unless being stored for a long period of time) so it's not going to hurt to pop them in the charger to top them up after they've been used.


----------



## axd

JBorneu said:


> Ahoy there
> 
> I created this guide because I felt we lacked one single comprehensive guide which tells newbies how to use Li-ion cells in a safe manner in their LED flashlights. Now I know why: At least the "comprehensive" part is impossible.
> 
> ...



Hello,

If it's OK I'd like to transfer this post to the CPFWiki.
Reasons are


other people can extend the text (now only sysadmins or the original writer can do that) - especially with comments that pop up later in the thread: it is extremely tiring to having to read a whole thread to distill information...
the text can be shortened a bit
As a side issue, I think that a lot of knowledge that can be found on CPF is currently hidden in thick layers of thread comments. IMO it would be good to condense posts into wiki articles - but I'm aware this is too much asked from most CPF users.


----------



## SilverFox

Hello Axd,

I think it would be OK.

If there are any objections from JBorneu, we will address those at a later time.

Tom


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## timmmm864

Thanks JBorneu for an extremely informative post.


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## tsmith35

Black Rose said:


> In the end, these protection circuits (baattery and driver circuit) are simply electronic devices that could fail.
> Should the protection circuit fail, you are left to your own devices to determine when the light will go dark.



The general idea behind multiple safety layers is to decrease the possibility that failure of a single layer will cause the entire system to fail. My car has 3-point seat belts, front & side airbags, anti-lock brakes, vehicle stability control, and multiple crumple zones. Is it death-proof? No, of course not. But the failure of any one safety component in a potential collision won't mean certain death under most circumstances. Especially if the operator takes care and pays attention to what he is doing (the most important part).


----------



## kito109654

Thank you for this easy to read and understand primer on lithium cells. It helped this newbie out. :twothumbs


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## Midnight Oil

I have a regulated Nailbender XRE-R2 with a 1.2-4.2V buck/boost driver in a Solarforce L2. It pumps out approximately 225 OTF lumens on high according to its sticker.

Last night, I let the light run on high off of a new AW 18650 2600mAh @ 4.16V fresh off of my Shekor charger.

The light ran for almost exactly 2 hours, then flickered and turned off---the over-discharge protection of the battery had kicked in.

I let the cell sit and rest for about 20 minutes and its resting voltage slowly climbed back to 3.17V, at which point I popped it back into the charger. I measured its resting voltage this morning and it was again at 4.16V.

A bit of context for my question below --- member Vidpro in another thread mentions that the voltage corresponding to a given remaining cell capacity is a function of the discharge rate. In other words, two cells with identical remaining capacity will register different resting voltages if they have been discharged at different rates: the one discharged at a higher rate will register a lower resting voltage.

Given that my light was on high for the entire duration of the 2 hours, hence the draw was high, did I really overdischarge the cell? Have I done any harm to it?


----------



## Mr Happy

Midnight Oil said:


> A bit of context for my question below --- member Vidpro in another thread mentions that the voltage corresponding to a given remaining cell capacity is a function of the discharge rate. In other words, two cells with identical remaining capacity will register different resting voltages if they have been discharged at different rates: the one discharged at a higher rate will register a lower resting voltage.


I don't think this is so. If you measure the voltage of a cell under load, the observed voltage will be lower under higher loads due to the effect of internal resistance. This means the protection circuit will cut in sooner, before the cell has been drained as much. If you then look at the resting voltages after the discharge has been stopped the cell discharged at the higher load will have a higher resting voltage and a higher remaining capacity than the cell discharged at a lower load.

The resting voltage is the stable voltage recovered after the load has been removed. In every case a higher resting voltage on the same cell indicates a greater remaining capacity.


----------



## 45/70

Midnight Oil said:


> ......The light ran for almost exactly 2 hours, then flickered and turned off---the over-discharge protection of the battery had kicked in.
> 
> I let the cell sit and rest for about 20 minutes and its resting voltage slowly climbed back to 3.17V......



I just thought I'd mention that if the protection circuit in the 18650 tripped, you would not be able to read any voltage but zero, from the cell, until it was placed in a charger to reset the PCB. I'm not familiar with your light setup, but I rather imagine that the light shut down, and not the 18650.

As for Mr H's excellent explanation, I think that is likely what Vidpro actually meant. Most protection circuits in the cells we use work best at medium to high current loads. Using protected cells at very low current levels, runs the risk of over discharging the cell.

Dave


----------



## Midnight Oil

45/70 said:


> I just thought I'd mention that if the protection circuit in the 18650 tripped, you would not be able to read any voltage but zero, from the cell, until it was placed in a charger to reset the PCB. I'm not familiar with your light setup, but I rather imagine that the light shut down, and not the 18650.
> 
> As for Mr H's excellent explanation, I think that is likely what Vidpro actually meant. Most protection circuits in the cells we use work best at medium to high current loads. Using protected cells at very low current levels, runs the risk of over discharging the cell.
> 
> Dave


 
Thank you, Dave and Mr Happy for clearing this up.

VidPro, if you read this thread, sorry for misinterpreting your explanations.

Much to learn I have.

Dave, about whether it was the light or the battery that decided to quit... My NB drop-in has a buck/boost driver and can run off of a single AA. That's why I think it was the battery, because the voltage didn't go so low that the boost circuit could not be powered to light the light. Isn't the protection threashhold of the AW cells set around 3.2-3.5V or so? Or it could have been that there was no way to stay in the high mode, but the cell could have continued to power the medium and low modes with the help of the boost driver?

So the consensus sounds like I did over-discharge the cell. Shame shame. Well that's the only time and the last time. The cell seems to have fully-recovered, as far as my DMM tells me. In light of this, I have to say runtime for this drop-in is a bit disappointing. I was expecting a solid 2 hours on high without over-discharging the cell. Unless my expectations were totally unrealistic to begin with. I hope my XPG-R4 with identical drivers will do better.

BTW, Dave, what is 45/70, because there is also a member old4570? You're not the same guy, right?


----------



## 45/70

Midnight Oil said:


> Isn't the protection threashhold of the AW cells set around 3.2-3.5V or so? Or it could have been that there was no way to stay in the high mode, but the cell could have continued to power the medium and low modes with the help of the boost driver?



Protection circuits vary, but I think usually they trip around 2.50-2.75 Volts. This is somewhat dependent on the amount of current load the cell is under. If the current is low enough, there is a point where most protection circuits won't trip at all!

Yes, I think your suggested scenario is likely. You might check and see if the light does, in fact work at the lower levels the next time this happens. Also, I don't think you necessarily over discharged the cell. Keep in mind though, that Li-Ion cells prefer shallow discharges over deep discharges. The cells last a lot longer with the former. Personally, I wouldn't discharge LiCo cells beyond where, when rested a minute, they recover to 3.6 Volts. Normally, I aim for ~3.8 Volts.



> BTW, Dave, what is 45/70, because there is also a member old4570? You're not the same guy, right?


The "45/70" comes from the rifle caliber of the same name. I can't actually speak for old, but I think he's referring to it also. And yes, we are two different Guys. It's really pretty easy to tell us apart. Being on the other side of the Planet from me and all, he's the one, along with his neighbors in N.Z. that walk around upside down all day. At least that's how it looks from my perspective. 

Dave


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## jacksmith

+1, this is really do for me as a newbie! thank you, *JBorneu* !


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## hawk45

Glad I read this, it answered a lot of questions. Thank you for taking the time to post a wealth of knowledge. 

Looks like last time the original post was updated was in 2010, maybe an update with the latest and greatest recommended batteries and changers available would be beneficial for 2012?

Cheers and thanks again!
Hawk


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## TSellers

As I've gone through the threads I've seen some real good tips on this subject. I recall reading one post that had a real good summary of charging and hadling tips, and I cannot find it again. I thought there may be a sticky on it as well, but perhaps I missed it? So my thought was a thread that summarized just safe handling practices for these cells, my apologies if I've missed one that exists already. Here's my contribution to that subject that I don't recall seeing before:

One tip in the forum is to not leave the room while you are charging Li Ion cells. Someone else mentioned doing it outside. Well outside may not work so well if you live in an apartment or in winter, but if you have a barbecue on your deck or balcony or back yard perhaps it could. Just run an extension cord over to the BBQ and charge it in there, close the lid if there is precipitation or curious ravens about. In summer, if you have a fireplace, you could place your charger in there as well and if the charger vents or catches on fire the smoke and toxic fumes go up the chimney.


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## LEDninja

*Re: Summary of 18650 charging and handling tips*

You thinking of this?
http://www.candlepowerforums.com/vb...-Using-Li-ion-cells-in-LED-flashlights-safely


----------



## TSellers

Yes that's the one. Thanks you very much for taking the time to get me pointed back to that. I must be pretty dense to have not noticed the give away forum title "*Smoke and Fire, Hot Cells and Close Calls - The dangerous side of batteries" *

Sometimes I groan when I see people asking obvious questions that have been answered numerous times, now I'm one of them. I guess I better learn some humility from it then. 

My only thought now is as that thread was originated in 2008, would an updated version be warranted now?

Thanks again.


----------



## TSellers

I have another question to clarify. I've noted that it is accepted that you should never use an unprotected 18650 cell in a 'multi cell' light. But I'm wondering if that actually means, 'a light that has cells in series'. If I read it right, the danger comes from cells in series going into a state of reverse polarity due to dichotomous internal resistance. However if you have a battery pack with 4 cells in parallel such as the optional Spark SX5 belt pack, is this multi cell warning still germane to this setup? Can cells in parallel still suffer the same fate at either the charge or discharge cycles?


----------



## VidPro

Parallel li-ion is a lot less things to deal with than series, you could get away without protection easier, as long as you know what you doing. It works out good.

If it is "non-protected" the least is having a cut-off to keep it (all of them) from the deep discharge. 
Charging goes ok and is simple, with parellel li-ion (using the same proper charge methods). One huge parallel setup I use has just one mondo doubled up protection and fusing for the whole parellel setup, has worked for years, uses proper charging and non-operation cut-off. 
If there was any issues it comes when more of the cells are going bad, and the parallel array is still treated as if all the cells are there and working. 

Some scenarios to think out:
if . . One cell item is bad, and the whole pack is getting a "Pack" charge, the bad cell is not fully charging, and taking on a lot of waste heat. If the charge rate was normal for one cell (takes forever to charge) then the heat buildup would be way lower. If the charge rate instead was 4X for the 4X batts, then one bad cell could end up with a very high charge rate hitting it, only because it is bad.
When you parellel 4 cells in, and 4X a high charge rate TOO, then you would want to be more aware of any bad cell in the group. One bad cell can take a majority of the current going in, and end up very hot.

If . . the whole group is going bad all at the same time, and they all are not "accepting charge" they will all heat up more uniformly. It took a lot of current to get a parellel set that was all bad to get hot. If the cells were originally matched in age and brand and type and mostly in capacity and all. And all the cells were used uniformly together (Parallel), there is a better chance that they will all be dying about the same way. And from the outside of the pack, what is happening would be easily observable. 

if . . All cells are bad , except one, and one is doing the work of 4. on discharge. that should be noticable in a lot of things, before someone charged it again.

If . . any of the cells Popped, if that anode disconnect is "activated" due to a single pressure buildup, the cell that popped is no longer "in that curcuit", and what is left takes on the discharge and charge. Whatever that would mean to the way it is being used. If any of them pop, that could be from the cells being bad, or the charge or discharge rates or heat, or anything that caused it to build up that kind of internal pressure. 

Bad cell: referring to one that will not charge fully, does not finish charging using standard charging, does not "accept charge" as it should, and instead wastes the power going in, the wastes being internal heat in the cell. A cell that self discharges, and the voltage drops, the other paralelled cells will keep discharging into it.
Popped: one that reads no voltage always, because the safety pressure thing disconnected the cell from its innards.

parellel ni-?? charging not so simple.


----------



## Norm

TSellers said:


> My only thought now is as that thread was originated in 2008, would an updated version be warranted now?


All the information in this thread is still relevant.

Norm


----------



## TSellers

Thanks for the updates, good to know.


----------



## yoyoman

I'm not an expert and cannot say the information in this excellent thread is still relevant. But I can say that the information is very useful.

A lot of the noise in this thread is because people focused on the point that Li-ion cells can be dangerous. As clearly stated, the key word is can. and it is true.

I also think it is important to emphasize the point that Li-ion cells don't have memory problems. I can put freshly charged cells (4.2 V) in my light and go play in the dark. When I come back, the cells are at 3.7 or something similar, and I can pop in them in a high quality charger (CC/CV) and charge them back to 4.2 V with minimal impact on their long term life. No need to get close to the edge (2.5 - 3.0). 

Treat your Li-ion cells with respect and they won't become terrorist cells.


----------



## germanium

I have stopped using loose cells based on LiCO for some time. I now use only LiFePO4 based batteries from K2Energy. I found there capacity to be very competitive to LiCO batteries & furthermore usable in more devices without issues. Forget using LiCO regulated batteries as even if the do work in devices that would not be compatible with LiCO otherwise the regulator contributes to the heat signature pushing the battery closer to the temperature limit of the battery itself. Run time tests I've done have shown the K2 Energy batteries to have greater capacity than all the regulated LiCO type RCR123 batteries I have tested. The LiFePO4 batteries do not contribute to the heat signature of the light as the regulated LiCO type batteries do. The battery compartment stays much cooler with the LiFePO4 batteries & the runtime was 50% higherwith the K2 energy LFP123 (RCR123) than all the regulated LiCO types I have tested. This is a battery that is at least somewhat abuse tolerant & suitable for most devices that take CR123 batteries


----------



## TSellers

germanium,

I had a look at the K2Energy site, and some of your previous posts, it is apparent you are a crusader for this cause, which is fair enough. It seems difficult to determine how many people have been field testing the use of these cells and I'll do some more research. Is it correct for me to assume that there are 2 options for many LED devices, you could use either their 18650E which would give you 3.2v and 1500mah, and the other option may be to use 2 LFP123 cells in series, which would only give you 600mA but a bright light while it lasted? Would the only downside being the need to carry 8 cells and change them 4X more than the equivalent LiCo 18650 cell?


----------



## germanium

TSellers said:


> germanium,
> 
> I had a look at the K2Energy site, and some of your previous posts, it is apparent you are a crusader for this cause, which is fair enough. It seems difficult to determine how many people have been field testing the use of these cells and I'll do some more research. Is it correct for me to assume that there are 2 options for many LED devices, you could use either their 18650E which would give you 3.2v and 1500mah, and the other option may be to use 2 LFP123 cells in series, which would only give you 600mA but a bright light while it lasted? Would the only downside being the need to carry 8 cells and change them 4X more than the equivalent LiCo 18650 cell?


An LFP18650 has only slightly less than triple the energy storage as the LFP123. Since you can use 2 of the LFP123 batteries in the place of 1 LFP18650 the 2 LFP123 batteries will last slightly more than 2/3rds as long as the LFP18650. On most LED flashlight there is a switch mode regulator & this regulator draws half the current when being fed twice the voltage so if the light draws 2 amps on the LFP18650 it will only draw 1 amp from the set of 2 LFP123 batteries. You would need about 6 LFP123 batteries to match the 2 LFP18650 batteries & would have to change them 3 times instead of 2.
The reason I'm so impressed with the LFP123 batteries is that they seem to deliver the promise of 50% of the capacity of the nonrechargable counterpart where the LFP 18650 is not there yet. They are about 50% or less of the capacity of LiCO 18650 batteries.


----------



## TSellers

I think I just learned something from this post I did not realize. I had assumed if you placed 2 cells in series you got twice the voltage and the same amount of mAh. But it appears that the regulator in the light will change that, so you end up with more potential mah than I originally thought.

Does that mean if you have a light like the Spark SD52 that uses 2XAA cells but with their regulated circuit accepting up to 7.6v, you could use the 3.2v LiFePO4 AA cells and get a lot more output?

BTW, as a follow up on your post I contacted K2Energy to see about getting their cells in Canada. There are no K2Energy dealers in Canada. For now it will be a deal breaker for most Canadians. The reason for that is due to USPS regulations US Dealers cannot ship Li Ion via USPS. The alternative, getting small orders via UPS and Fedex from the USA is a nightmare that most Canadians now avoid, so it will not work. However Canadian Postal regulation 3.2.2.8 allows for Li Ion cells if they follow certain prescribed protocols as set out in the prevailing Shipment of Dangerous Goods Act, and EMS seems to dovetail into that so Hong Kong/Chinese eBay sellers are successfully selling LiFePO4 into Canada, so it will boil down to finding some other reputable source there rather than in the USA I'm afraid.


----------



## germanium

TSellers said:


> I think I just learned something from this post I did not realize. I had assumed if you placed 2 cells in series you got twice the voltage and the same amount of mAh. But it appears that the regulator in the light will change that, so you end up with more potential mah than I originally thought.
> 
> Does that mean if you have a light like the Spark SD52 that uses 2XAA cells but with their regulated circuit accepting up to 7.6v, you could use the 3.2v LiFePO4 AA cells and get a lot more output?
> 
> BTW, as a follow up on your post I contacted K2Energy to see about getting their cells in Canada. There are no K2Energy dealers in Canada. For now it will be a deal breaker for most Canadians. The reason for that is due to USPS regulations US Dealers cannot ship Li Ion via USPS. The alternative, getting small orders via UPS and Fedex from the USA is a nightmare that most Canadians now avoid, so it will not work. However Canadian Postal regulation 3.2.2.8 allows for Li Ion cells if they follow certain prescribed protocols as set out in the prevailing Shipment of Dangerous Goods Act, and EMS seems to dovetail into that so Hong Kong/Chinese eBay sellers are successfully selling LiFePO4 into Canada, so it will boil down to finding some other reputable source there rather than in the USA I'm afraid.



Actually the mah's remains the same. The switch mode regulator converts high voltage low current to lower voltage higher current. As the batteries drain & the voltage goes down the regulator increases the current draw in order to maintain performance. Inserting a higher voltage battery does not really noticeably increase the performance of the light. As you increase voltage you increase runtime for a given mah rating & brightness. you do not actually increase the mah rating or noticeably increase brightness with the extra voltage. This extra current draw as the battery drains serves to kill the battery faster though so most manufacturers allow their lights to go out of regulation eventually once a certain voltage level is reached. This serves to extend the usable life of non rechargeable batteries as opposed to maintaining tight regulation till drained & serves to be a warning to replace rechargeable batteries as by this time they are drained & running them longer could damage them to the point of not being able to recharge them in some cases.


----------



## lightyearsaway

Ok I am curious then... How about those Li-ion batteries that are in smartphones and cell phones and digital cameras etc? Same rules apply? Don't overcharge, don't discharge too fast, and do not leave them unattended? If this is the case, there are a whole world of people out there who are charging their batteries wrong. I am curious to know if these flashlight type rechargables are different in any way from those in typical consumer products? I am planning on buying some flashlights which require a 18650 battery, but after reading here, I am actually skeptical to do so. I can't just wait around while my batteries charge up, have no idea what is the ideal charge time for slow charging either. I leave my mobile phone charging all night, sometimes the camera batteries charge all night too, many times while I am away. So far I have been lucky I guess? I may stop doing this now after reading the first post. 

Do not chargable CR123's pose any risk in flashligts if not used for long periods of time?? Or is this terroist cell issue only for rechargable batteries? I so wish Eneloops would come out with both a CR123 and an 18650, I would feel somewhat better.


----------



## yoyoman

Your smartphones, cell phones and digital cameras all have dedicated chargers and protection circuits all over the place. The chargers and protection ensure they don't charge too fast and they don't overcharge. The protection in the device ensures they don't over discharge. If you have a good charger, protected cells, low voltage warnings in your dropin, then li-ions in flashlights are safe. 

Lithium primary CR123A cells don't leak. Care should be taken when using more than 2 cells in a light. Take care that the cells are balanced - have the same or close voltage. One fresh cell and one depleted cell is a recipe for disaster. Never try to recharge lithium primary cells.


----------



## lightyearsaway

yoyoman said:


> Your smartphones, cell phones and digital cameras all have dedicated chargers and protection circuits all over the place. The chargers and protection ensure they don't charge too fast and they don't overcharge. The protection in the device ensures they don't over discharge. If you have a good charger, protected cells, low voltage warnings in your dropin, then li-ions in flashlights are safe.
> 
> Lithium primary CR123A cells don't leak. Care should be taken when using more than 2 cells in a light. Take care that the cells are balanced - have the same or close voltage. One fresh cell and one depleted cell is a recipe for disaster. Never try to recharge lithium primary cells.



Normally I would plug the phone in directly to the wall through the USB cable, but I think the phone itself has all kinds of protective circuits. Though I do know some phone batteries have also exploded. Other than the charges that were recommend at the beginning post, are their other brands or charges that others would recommend? I am looking for a very good charger, that last thing I need is a bomb. Of course the primary cells are like Alkaline batteries in a way, they cannot and should not be recharged.

For the CR123s basically then when I take them out of the packages from the store, if I am using two in one in a flashlight, I should put a volt meter to them to make srue I find two that are of equal or close voltage? I assume the same care should be taken with a flashlight that needs 2 18650s? If I am only using one in a flashlight there is much less risk correct? 

I will have to check if the flashlights I am about to buy have that low warning light. That is Nitecore SRT 5 and 7. I think they do, but I need to check. I know the EA or EC series does.

How long can the 18650's hold their charge before they HAVE to be removed from the flashlight? Or depleted cells are ok to recharge? Or is that the problem? If a depleted cell is charged it may also explode when trying to be recharged?


----------



## yoyoman

HKJ does excellent reviews of cells and chargers. The Xtar VP1 is a recently released unit that gets good reviews. It is flexible and you can select different charging rates to match the requirements of the cell (mainly size or capacity).

Some very good lights/dropins don't have low voltage warnings. They provide regulated output for a range of voltage and "drop out" of regulated and go direct drive. In use, you'll notice the dimming and know to switch cells. In some ways, these designs are based on lithium primary cells, which can be sucked dry. 

The key is to have a volt meter to be informed. What was the voltage of the cell before charging, after charging, after a good, long walk, etc. Check the voltage of the cell before going camping. Etc.

Li-ions hold their charge (more or less). Some flashlights, particularly with electronic switches, have a parasitic drain. But this is generally very low and not an issue if you use your light regularly.

Li-ions don't have memory which means it is fine (even good) to top them off when the voltage gets down to 3.8 or even 3.9. Some chargers won't kick in unless the v is below 3.9. There is no need to wait for the protection circuit on the cell to cut off power. You can top off the cell well before the cut off will trigger.

I use a simple volt meter from cottonpicker's in the market place. Great for li-ions, but not for other types of cells.

A good charger will recognize cells that have been overdischarged. They either won't charge the cell or will start on a very low charge input. 

Another reference, in addition to the threads on this forum, is Battery University. When used properly and with awareness, li-ions are great.


----------



## Psychonaut

I am getting a modded light wich takes over 5A per cell. I am getting the 20R cells (unprotected) for that. So the 2000 mAh cells are discharged with more than 2C, which is described to be dangerous in this guide. Is this still up to date? Or is it OK for such cells?


----------



## LEDninja

Psychonaut said:


> I am getting a modded light wich takes over 5A per cell. I am getting the 20R cells (unprotected) for that. So the 2000 mAh cells are discharged with more than 2C, which is described to be dangerous in this guide. Is this still up to date? Or is it OK for such cells?


Get the new 3100 mAH cells.


----------



## AnthonyMcEwen2014

oops, made valid points but CBA to argue or start and argument so have deleted the text that was here.

Good guide though.


----------



## RetroTechie

germanium said:


> TSellers said:
> 
> 
> 
> I had assumed if you placed 2 cells in series you got twice the voltage and the same amount of mAh. But it appears that the regulator in the light will change that, so you end up with more potential mah than I originally thought.
> 
> 
> 
> Actually the mah's remains the same.
Click to expand...

germanium is correct, the mAh's stay the same. But at 2x the voltage, the same mAh's give you 2x the amount of energy (in Watt-hours). Which is logical if you're using 2x as many cells. :duh2:

If there's a switching regulator in the light (as will be the case for a modern, efficient LED flashlight), the same power draw @ 2x the voltage means 0.5x the current (mA's). At the same mAh rating, that gives you 2x the runtime. Which again is logical if you're using 2 cells vs. 1.

So far the theory! :tired: In practice, the mAh's you can get out of a cell, depends on the current draw. At 0.5x some current draw, a cell will likely show higher mAh capacity than at 1x that current draw. Depending on current draw and cells used, the difference may be small, or it may be big. And then you should know that voltage conversion circuitry _usually_ operates (_somewhat_) more efficiently at higher voltages.

Summarized: putting multiple cells in series may help in more ways than one. But how much, might not be noticeable (apart from the obvious doubling of runtime you could expect). On the flip side: there's some issues with a multi-cell setup (for example, dangers of mixing cells in various state of charge) that you don't have with a single-cell powered light.


----------



## Disciple

yoyoman said:


> Lithium primary CR123A cells don't leak.



From personal experience: at least the Chinese-made ones sometimes do.


----------



## yoyoman

^ Bummer


----------



## TSellers

> From personal experience: at least the Chinese-made ones sometimes do.



Probably is Brand dependant. I've been using GP Brand for years and so far not noticed any problem, (do my best not to leave depleted cells in the devices that they were in). Now going to try some other CHinese Brands, just got some Nitecore and some cheap 'WF' brand to try. If any leak it will probably be the latter, and I won't be surprised if their capacity is a lot less than the other two brands mentioned here.


----------



## Psychonaut

LEDninja said:


> Get the new 3100 mAH cells.


 Is there a high drain version similar to the 20R with 3100 mAh?


----------



## origamimavin

Great writeup! I just got my first flashlight that takes Li-ion, so this was good information. I'm still looking up information on unprotected 10440's (i just shocked myself, somehow, by removing the safety from it), and am trying to learn as much as i can about the safety of them.


----------



## MFMIYP

Is there anything to be aware of with stacking protected rechargeable Li-ion's into a light? I recall reading somewhere that it was a must-not.


----------



## Disciple

MFMIYP said:


> Is there anything to be aware of with stacking protected rechargeable Li-ion's into a light? I recall reading somewhere that it was a must-not.



This is done by a lot of people around here including me, so it's certainly not a "must-not" to everyone. Nevertheless protection circuits are not perfect (some don't work at all) so you should still make sure that any series-wired Lithium-Ion cells are properly balanced. This means that the cells are same type and age, have been tested to have similar capacity, and are starting at the same voltage every time.


----------



## MFMIYP

So there are two types of these rechargeable Li-ion batteries: protected, and unprotected, correct?

Some lights using multiple batteries stack in series (meaning one goes in the body/tube, and than another right behind it till full), and some use battery magazines; which I don't yet know if those are actually wired parallel or series, but in any case taking for example the Olight M3X, that's a series stacking light, and so my question going out now is does anyone stack non-protected batteries as a result of my initial question? Further, what more can be said about the concerns of stacking protected batteries in the first place? Or un-protected batteries for that matter?

I get you Disciple, and I'm willing and able to invest in everything it takes to pay close attention to the status of my batteries, and definitely appreciate your input very much. For whatever reason, a windfall of lights is coming to me as a result of my impulsiveness. Of course now there's no turning back, and I do enjoy the details of things which is what brought me here.

So thanks. Lastly what's with the "Image Verification" ...is that all the time??? yikes.


----------



## Disciple

Disclaimer: I am not a battery expert. I an regurgitating what I have learned here.

Battery magazines (or carriers) can be either series or parallel, or a combination (2s2p). I would not use unprotected cells in a series-wired configuration. If you are sure that all cells are wired in parallel then it should be reasonably safe to use unprotected cells (still of the same type) as they will inherently balance. See Li-Ion Parallel Charging for testing and explanation. However it may still be possible to over-discharge the cells depending on the circuitry of the light, and this _can_ be dangerous as it may damage the cells in a way that can later cause an internal short (read: "vent with flame" which means explosion in a sealed light). If you choose to use unprotected cells (either a single cell or in parallel) make sure the light has a low-voltage cutoff or inherently shuts off before the cells are over-discharged. The forward bias voltage of the LED often serves this purpose. See HKJ's battery selection guide for more. In any light an unprotected cell is at greater risk from an external short or from over-charging from a malfunctioning charger, therefore the protection circuit adds an extra layer of safety in any application.

Series-wired cells are more dangerous because one cell can drive another (depleted) cell into reversal causing a breakdown of the internals of the cell and smoke/fire/explosion/etc. This is why we must check that the cells are properly balanced. 

Since charge state can be inferred from voltage in Lithium-Ion cells we can use voltage checks to check capacity. When you charge a set of sells for series application check the voltage after letting them rest for a few minutes. The voltage should be nearly the same. (+/- 0.02v I believe I read? I'm not sure; research this yourself.). A low voltage could be the sign of a degraded cell. When you first use the cells (in series) periodically stop, open the light, and check individual cell voltage, again after a few minutes of rest. The cell voltages should drop at the same rate; one dropping faster than another is a sign of a cell with diminished capacity, and if severe it could result in that cell being depleted early and driven into reversal.

By "Image Verification" do you mean a form of CAPTCHA? If so that must be because you are a new member because I don't see those.


----------



## MFMIYP

Thank you, Disciple. A lot of information to consider. I appreciate your reply very much. The CAPTCHA thing is gone too. What about below-freezing temps with these batteries. As far as plain storage, loading them with actual use, or charging while too cold? Seems like I hear the primary type 123 are good to go in basically all temps. I'm concerned about damaging my rechargeable ones. Thanks again.


----------



## Disciple

I don't have that data. I'll see what I can find.


----------



## thedoc007

MFMIYP said:


> What about below-freezing temps with these batteries. As far as plain storage, loading them with actual use, or charging while too cold?



Storing them cold is fine, and if they will work, using them cold is fine too - their performance will be lower in extreme cold, but they will warm up in use, and there is no safety issue there I am aware of. But DO NOT charge a frozen battery - that can definitely lead to problems. 

From Battery University:"Many battery users are unaware that consumer-grade lithium-ion batteries cannot be charged below 0°C (32°F). Although the pack appears to be charging normally, plating of metallic lithium can occur on the anode during a subfreezing charge. The plating is permanent and cannot be removed with cycling. Batteries with lithium plating are known to be more vulnerable to failure if exposed to vibration or other stressful conditions."

So to repeat, DO NOT charge any lithium ion cell that is below freezing. Storing or using them cold is fine.


----------



## TSellers

> So to repeat, DO NOT charge any lithium ion cell that is below freezing. Storing or using them cold is fine



Thanks for the reminder. I often place the batteries from the headlamps I've been using for a night ski straight into the charger as soon as I come in the door so I won't forget. In fact I did that tonight. Although they are usually coming in from a warm car ride, it's well worth it for me to always be aware of that.


----------



## BarneyBG

Quick question...
According to this thread and another one about circuit protection - the protection is there just in case, it shouldn't be relied upon and it shouldn't enter into any "estimations" (e.g. "my cell is protected, so I can torture it"), right? OK. But what is the reasonably safe voltage limit that I should "train" myself not to cross? It says that 3.0V is the absolute minimum for discharging, but if I'm outside, using my torch - at what voltage should I stop using my TF 18650-protected? I wanted to test how much can I use my torch so I turned it on and stopped it as soon as the voltage turned 3.6V. The whole process took 3.5h so I assumed that's the reasonably safe time I can use it. True or not? Can I squize-in some more time or it's pushing it with negligible benefits?


----------



## Swedpat

Thanks for the information. More than 3,5 years late to say it but this is still valuable and actual.



JBorneu said:


> Don’t discharge until the protection circuit kicks in



So much one needs to know when it comes to batteries, and I am still learning more. Do I understand this right that I therefore never should use Li-ion batteries in regulated flashlights who lacks over discharge protection suited for the voltage of the used Li-ion(s)? 

What I have read the overdischarge protection of a 3,7V Li-ion kicks in at 2,5V.

If I then use 2x18500 or 18650 to run, for example, a Malkoff M61SHO dropin, Information from the site: "_*The input voltage is 5.5- 12 volts.*__ Below 5.5 volts it will drop out of regulation. Below 5 volts it will begin to flash and below 4.5 volts it will shut off_. " 

This dropin consequently doesn't work at all with a single cell. But with two cells it means that it drops out of regulation when the voltage of each cell is 2,75V. And because this dropin is intended for two Li-ions I presume it's ok to run the light until it drops out of regulation, though the voltage is just slightly over the cells protection limit. 

But how to do with a Malkoff M61: "_The input voltage is 3.4 - 9 volts. Below 3.4 volts it will drop out of regulation and run direct drive_." 
Consequently it should be considered as "forbidden" to run this dropin at all with two Li-ions: the light will be flat regulated until the protection circuit kicks in and because there is no warning for when this will occur; is that a correct conclusion ?


----------



## StorminMatt

One thing I like to do with NiMH is an occasional runtime test. This way, I know how long my light will run if I use it for long stretches. It also gives me an idea of the health of my batteries. Similar testing, along with voltage readings at regular intervals, might not be a bad idea with Li-Ion. If you know about how long your batteries will run a light before voltage drops below a certain level, you are less likely to overdischarge them. And since most Li-Ion chemistries generally experience gradually decreasing capacity over their lifetime (unlike NiMH), doing runtime tests at regular intervals will let you know how long you can use your light as the batteries age.


----------



## TSellers

> Do I understand this right that I therefore never should use Li-ion batteries in regulated flashlights who lacks over discharge protection suited for the voltage of the used Li-ion(s)?


I would use a protected cell in a light that does not have a driver with a shutoff algorithm. (Actually I would never use a light that does not have a protection circuit built in).



> What I have read the overdischarge protection of a 3,7V Li-ion kicks in at 2,5V.


You mean that's where a protection circuit kick's in? I think most are higher than that are they not? I thought 2.5 was the level cited by Battery University as the lowest level a Li-Ion cell can by taken to for up to a week.



> I presume it's ok to run the light until it drops out of regulation,


2 cells in series your problem is not the low voltage cutoff, if they were unprotected cells then your concern is with internal resistance causing one of the cells to reverse polarity and vent. Thus you need to use balanced or protected cells in that configuration.



> But how to do with a Malkoff M61: "_The input voltage is 3.4 - 9 volts. Below 3.4 volts it will drop out of regulation and run direct drive_."
> Consequently it should be considered as "forbidden" to run this dropin at all with two Li-ions:


Can't really understand your question here. Above you mention that the drop-in needs 5.5-12V, then this appears to state the same drop in uses 3.4-9 V, or am I getting it wrong?

I feel comfortable using unprotected cells in my single cell Spark headlamps for example because they have good protection built into them already for low voltage, overvoltage, and reverse polarity. If I were running any 2 cells lights in series I'd use protected cells due to the potential issues with internal resistance from unbalanced cells causing problems with one of the cells.

These opinions are just what my understanding of general guidelines for Li-Ion are from reading the comments of others in the fourms that have more experience than me (that's why I waited 3 days before replying), and from the Battery Universitie's website, so of course you should double check anything I've said before potentially acting on it as good advice.


----------



## Swedpat

TSellers said:


> Can't really understand your question here. Above you mention that the drop-in needs 5.5-12V, then this appears to state the same drop in uses 3.4-9 V, or am I getting it wrong?



Sorry, expressed me a bit unclear. I compared between the standard M61 which is regulated between 3,4 and 9V and the slightly higher output M61SHO which is regulated between 5,5 and 12V. However I think the standard M61 actually drops out of regulation at slightly higher voltage than 3,4V: with several of my different M61 dropins the brightness is lower with a single 17670/18650 than 2xCR123 or becomes lower after a short while.

I only have high quality Li-ions and only use the same brand and model in pairs. Once I have started to use a pair I mark them and let them continue together. The charger is Pila IBC. I don't know how much they differ from each other. The same brand and model of the higher grade batteries should differ only very slightly I think?


----------



## NY09C6

I'm going on year 3 of running protected cells down until they cut off and then fully charging them. On average each cell is discharged and recharged 3 times per month.


----------



## TSellers

> The same brand and model of the higher grade batteries should differ only very slightly I think?



Well I'm actually running some unprotected cells in a Fenix TK76 in series. They are matched and I monitor and measure them each time they are charged in the same fashion as you. I do not use that light very much as it was given to us for evaluation, but in the long run I accept that I should be using protected cells in it, but at the moment, and given how rarely I use the light, I cannot afford to dedicate 4 expensive protected cells to it. I guess if I was going out on a field operation that I knew would be causing the light to get constant use I would simply swap the cells out for protected ones at that point. Ironically the place I really need to use 14500 protected cells the most is in AA cell packs for VHF radios, but those packs simply do not have the room, always seems to be the problem with protected cells in places you need them the most.


----------



## KITROBASKIN

NY09C6 said:


> I'm going on year 3 of running protected cells down until they cut off and then fully charging them. On average each cell is discharged and recharged 3 times per month.



Perhaps I missed something, Are these protected cells being used in a flashlight that is without low volt cut off protection? What size battery are they? Thank You.


----------



## NY09C6

Ultrafire 16340 cells in a JETBeam RRT-01. It's kind of a test for me.


----------



## BronzeLincolns

thank you for this bit of info.

i guess i was better off getting the OEM recommended non rechargeable panasonic CR123 1550mahs for the SRT7 i have on order. got 10 of them. i'm a total n00b to all this and i've pretty much been scared off of rechargeables by this thread haha. thanks again for the heads up.


----------



## lonesouth

When I read a review and see that the summary is that the cells are not good/recommended. Is there a risk that the cells will damage the light, or just that they will not work as advertised? 

I received some Ultrafire BRC18650s with a WF-502B I got on amazon. I understand that the batteries, in general, are garbage, but can they damage a light, other than flame-out? I checked the voltage and they are 4.195 fresh off the charger that came in the package.


----------



## thedoc007

BronzeLincolns said:


> i guess i was better off getting the OEM recommended non rechargeable panasonic CR123 1550mahs for the SRT7 i have on order. got 10 of them. i'm a total n00b to all this and i've pretty much been scared off of rechargeables by this thread haha.



If you do a search, you'll find that the majority of battery problems come from batteries in series configuration. If there is only one cell, the worst you can typically do is over-discharge it. But when you have two in series, if they aren't well matched, when one gets low, the other starts reverse charging it, and that's when you get venting with flame, and explosions. 

If you buy quality CR123 cells and only use them in matched pairs, your risk is low. But thinking you avoided the potential risk by buying primaries is just completely wrong. In my opinion, and that of others with far more experience, multiple CR123 in series is among the MOST likely to cause you problems.


----------



## BronzeLincolns

mixing batteries is just asking for trouble which is why i bought in pairs. while i am using a sequence of batteries they're the same battery and if the light goes dim im throwing both batteries away.

reading more on this stuff makes me glad i didnt opt for the streamlight protac HL 3 that takes 3 CR123s and two 18650s.


----------



## RetroTechie

I agree with thedoc007. Compared with 2x CR123A, using a single 18650 _might_ be the safer option. Even if that means using a rechargeable battery. And as a bonus, it's the cheaper option. 

2nd: Beside how you use them, the *quality* of the batteries is a deciding factor. Once you have found a good 18650 cell, all that's needed is use it properly. If you have a batch of 20 CR123A's with 1 bad one in that batch, it's only a matter of time before you hit that bad one. After using (say) 12 from that batch without any problems, you might not see coming what happens when you use the bad one.


----------



## BronzeLincolns

i'll probably be springing for the Vp1 or Vp2 charger from xtar with one of those nitecore 18650s in the near future. i'm gonna go through these primaries first though, or maybe i'll use them in my maglite. they're top of the line panasonics. i got a no payments or interest promo going on with BML thats running out so i might just use that to buy it but with the recall i may need to wait until they fix whatever problem they have with the chargers or just go with the VP1.

i'm learning that skimping on quality to save money isnt a good idea.


----------



## markr6

I keep all my batteries, chanrgers and most flashlights on the workbench in my garage. I also charge everything out there. I never realized how cold it actually got in there until I put a thermometer on the wall. With so many nights between -10F and 10F, the garage can get down to about 43° or so.

This is still safe to charge Li-Ions, right? Maybe more of a concern regarding the health of the cells opposed to charging at room temp?


----------



## SilverFox

Hello Markr6,

43 F is on the lower side of acceptable for Li-Ion charging. While you can charge down to 32 F you need to reduce the charge current at lower temperatures. Ideal low temperature for Li-Ion cells is 50 F.

Tom


----------



## markr6

Thanks Tom. I think I'll move all my batteries and flashlight stuff into the basement. I originally started in the garage since we just moved in and that workbench was already there. Need to find a nice, cheap desk or something and get some organization going down there.

And now that I think of it, those 100° summer days won't be very healthy for them either so sooner than later would be best.


----------



## Aquanaut

I am back after a long absence and picked up this thread. I have to add an "Imax B6 Ultimate" charger to the charger list. I consider it to be an excellent charger and have been using it for many years to charge not only Li-ion, but also NiMH and NiCd cell(s). I especially like the ability to balance charge Li-ion cells. I usually like to charge two cells at a time.


----------



## murrydan

*Li-ion EDC - is it too risky?*

Thread Merge - Norm

I just purchased a Peak Eiger that can take 10440.. I have read tons of material about using them safely, but there are still risks, _right_?

My question is: _Is it a bad idea to carry them in your pocket every day?_


----------



## StarHalo

*Re: Li-ion EDC - is it too risky?*

As long as you know your voltage and the light doesn't see any intense abuse, you should be fine.


----------



## murrydan

*Re: Li-ion EDC - is it too risky?*

I have never used Li-ion batteries and don't want to carry a "pipe bomb" in my pocket.. or am I just being paranoid?


----------



## ven

*Re: Li-ion EDC - is it too risky?*

I hope not


Thats all i have done for a long time,my advice "just in case" use a decent branded protected cell if gives more piece of mind:twothumbs

So as said,common sense,no ******fire cells,no ***** fire lights(unless surefire) and just enjoy your light,not to mention a good charger again xtar make some great chargers,no ****** fire ones........simple as that.

Most lights are ixp8 rated,so 1.5-2m drop and 2m+ under water...........most have been tested with more than that and been fine


So nothing wrong with being concerned,would not use paranoid as too stronger word and takes away any edc enjoyment imo.

Other options are IMR cells that are a safer li-ion chemistry but not protected...........

Dont let cells drain right down,if protected then will trip,more than likely the flashlight will tell you by either not allowing turbo (dropping a mode) for example
Time to charge,personally if i use a light i just top off the cells,its not counted as a cycle,so topping cell off 5 times may =a cycle of which most cells are rated for around 500 cycles...........lot of use!!! and newer cells will be purchased in the time it starts to go a little tired(UK spelling for sleepy,not as in tyre on cars :laughing: )


----------



## ven

*Re: Li-ion EDC - is it too risky?*



murrydan said:


> I have never used Li-ion batteries and don't want to carry a "pipe bomb" in my pocket.. or am I just being paranoid?




Read up,do research,nothing to be scared off,lots of horror stories,but thats like me telling you not to drive a car as people crash into you(in fact far more chance of that than an li-ion exploding)

Point being,research,decent branded cells and charger,dont leave unattended no matter what precautions as with anything,nothing can be relied on(if makes sense)
Example- leaving on over night whilst asleep,leaving on charge and go out,just dont leave alone for hours..............simple as that
Also voltmeters are cheap,check cells,also will be able to check charger after ...........charging. Should be around 4.2v after charge........

Lots of info on here,dont be put off............i am not!!!! no need to study for days,just the basics


----------



## murrydan

*Re: Li-ion EDC - is it too risky?*

Thanks for the reply. 

I have read that the protected 10440s are too long to fit in the Eiger (2mm longer), so I think they are a no-go.. If not *****fire, which brand would you recommend?


----------



## markr6

*Re: Li-ion EDC - is it too risky?*



ven said:


> Read up,do research,nothing to be scared off,lots of horror stories,but thats like me telling you not to drive a car as people crash into you(in fact far more chance of that than an li-ion exploding)
> 
> Point being,research,decent branded cells and charger,dont leave unattended no matter what precautions as with anything,nothing can be relied on(if makes sense)
> Example- leaving on over night whilst asleep,leaving on charge and go out,just dont leave alone for hours..............simple as that
> Also voltmeters are cheap,check cells,also will be able to check charger after ...........charging. Should be around 4.2v after charge........
> 
> Lots of info on here,dont be put off............i am not!!!! no need to study for days,just the basics



Exactly. Thought of a quote by Al Pacino from the movie Heat _*"you can get killed walking your doggie!"

*_Unfortunately Li-Ions have been painted as everything from fragile, delicate, extremely temperature-sensitive, pipebombs, flame-venting projectiles, and so on. We see a few incidences with photos of and scary words, allowing people even without first-hand experience to paint anything with that brush in a negative way. The publicity on Tesla didn't help.


----------



## ven

*Re: Li-ion EDC - is it too risky?*

Dont forget the laptop issues of past too,but imagine a 2.5t weapon,travelling at just 120kmph and to think i put the kids in it

My point being the kitchen is more dangerous,walking up the stairs you have more chance of killing yourself...........just takes 1 or 2 horror stories from probably misuse..............and all of a sudden 

Not taking away anything to do with safety,its all covered on here,go off advised cells and charger,all will be well:thumbsup:

Side note,i have some ******fire cells,even used the ******fire charger for a couple of years,as soon as green they were off,not left alone...........issue free

So its not just as straight forward as saying AVOID **** fire cells,with care and common sense they can be safe!!! just easier for newbies to take any element of risk away,besides them being a gamble in the 1st place,obv 5000mah go without saying a load of bull,however the fire cells are still stocked by some reputable sellers........

But my advice is just take away the 50/50 gamble,spend $5 more on a cell,and relax knowing its protected.........simple as that:thumbsup:


----------



## schizeckinosy

*Re: Li-ion EDC - is it too risky?*

Also remember you have a li-ion in your cell phone...


----------



## StarHalo

*Re: Li-ion EDC - is it too risky?*



ven said:


> spend $5 more on a cell,and relax knowing its protected



Protected cells just prevent draining too low, they don't prevent anything relating to temperature or overcharge.


----------



## HKJ

*Re: Li-ion EDC - is it too risky?*



StarHalo said:


> Protected cells just prevent draining too low, they don't prevent anything relating to temperature or overcharge.



The PCB protection will protect against over discharge, *over charge* and over current. Most cells has a build in PTC that will protect against very high over currents and over temperature. They do also have a over pressure vent that will disable the battery if the pressure gets too high.
I have a bit more explanation here: http://www.lygte-info.dk/info/battery protection UK.html


----------



## ven

*Re: Li-ion EDC - is it too risky?*

Thank you HKJ

They are a sensible choice for newbies or especially peeps who may not have confidence in the cells imo,a more piece of mind than anything,but obv should still be treated with respect as with any cell,just more so with li-ion.

Also make a more sensible choice in multi cell lights for beginners too.

As long as not relied on 100% regarding protection (anything can let you down at any point if man made)and as said treated with respect,then all should be well

So imho no its not too risky,only down side of 18650 cells is the actual light size for edc,some smaller cells may be more suited depending on where it is going to live on your person:thumbsup:

Right now for size and ease i am on IMR 16340 cell for my amazing d25cvn ti light for my edc.
Before that it was the excellent xeno S3A V2 on a protected 18650,quite a small light for its cell food.


----------



## HKJ

*Re: Li-ion EDC - is it too risky?*

I did even forget one protection, that is present in some newer cells. 

It is a fairly new invention, Panasonic calls it HRL (heat resistance layer). It is a layer placed between the two electrodes in the battery and will disable the battery if it get hot.
Any battery that explodes (oops: wents with flame) has to be very hot for this to happen, with the HRL layer this is not possible, the layer will stop the chemical reactions when the battery gets warm.


----------



## ven

*Re: Li-ion EDC - is it too risky?*



HKJ said:


> I did even forget one protection, that is present in some newer cells.
> 
> It is a fairly new invention, Panasonic calls it HRL (heat resistance layer). It is a layer placed between the two electrodes in the battery and will disable the battery if it get hot.
> Any battery that explodes (oops: wents with flame) has to be very hot for this to happen, with the HRL layer this is not possible, the layer will stop the chemical reactions when the battery gets warm.



That sounds an excellent idea/addition HKJ,i can only presume that a fault would cause the need for this protection or a heavily modded light thats been left on.

Its progression though,all seem to be going in the "safer" direction.

Thanks for info:thumbsup:


----------



## HKJ

*Re: Li-ion EDC - is it too risky?*



ven said:


> Its progression though,all seem to be going in the "safer" direction.



It does, look at videos where people shorts the newer Panasonic cells, they are very boring

I did also do a test myself (By accident):
In a usb power box with four batteries in parallel I put in four 3100mAh unprotected cells, but turned one of the cells backward. It only took a few second before I was clued in to my mistake: springs are not supposed to glow. I removed the warm batteries very fast and over the next days I tested them on a hobby charger. They did all have some damage, i.e. less capacity than expected. The battery I put in the wrong way could not even be charged to 4.2 volt.
This shows that the cell protection does not protect the cell from fatal damage, it is only supposed to prevent "went with flame" incidents.
If I had used protected batteries (i.e. with PCB), the over current protection would have tripped and I could just have turned the battery around at it would have worked.

LiIon manufactures does specify that you have to use an external protection with their batteries.


----------



## ven

*Re: Li-ion EDC - is it too risky?*

So the power box did not have protection as i read(will keep simple with 1 charger example) the i4,if i put a cell in wrong way,it should detect that,is this correct?

Thank you


----------



## HKJ

*Re: Li-ion EDC - is it too risky?*



ven said:


> So the power box did not have protection as i read(will keep simple with 1 charger example) the i4,if i put a cell in wrong way,it should detect that,is this correct?



Like most power boxes it uses two copper strips for the battery connection. It does have protection against over discharge.
The i4 is supposed to protect against this (I have not tested it).


----------



## murrydan

*Li-ion EDC - is it too risky?*

So, if a protected 10440 is too long I should still be ok unprotected.. As long as I play it smart. 

Most mishaps from user error? (over charge - over discharge)


----------



## ven

*Re: Li-ion EDC - is it too risky?*



HKJ said:


> Like most power boxes it uses two copper strips for the battery connection. It does have protection against over discharge.
> The i4 is supposed to protect against this (I have not tested it).




I am delving deep into the abyss of my head,the 2 cells,1 is asleep,the other digging as i type,i am sure i did put a cell in the wrong way but not 100% and caused no issue the other month,cant remember if on the wp6 or i4.

I have done it on a ******fire charger a few year back,it broke the 1 bay of the 2 bay charger,cell was fine..............the utrafire grey one(sorry cant recall model but sure the newer one stops charging,older version trickles still) and is pretty common on ebay,i used them for my fire torches as at time i thought were good,tbh they still work now,just in build and power/tint/quality is well worlds apart............but still of use if i need to go crawling back in my hole


----------



## HKJ

*Re: Li-ion EDC - is it too risky?*



murrydan said:


> So, if a protected 10440 is too long I should still be ok unprotected.. As long as I play it smart.



It can be very difficult to play it smart.



murrydan said:


> Most mishaps from user error? (over charge - over discharge)



That depends on the generation of batteries. A few years ago the risk was much greater (That does not make it a huge risk).

Over discharge will usual make permanent damage to battery and increase the risk of future accidents. But even with increased risk a modern battery is mostly safe.


----------



## ven

*Re: Li-ion EDC - is it too risky?*



murrydan said:


> So, if a protected 10440 is too long I should still be ok unprotected.. As long as I play it smart.
> 
> Most mishaps from user error? (over charge - over discharge)



Protection adds around 3-4mm on the 18650 cells,not sure with 10440,mishaps wise yes.


----------



## HKJ

*Re: Li-ion EDC - is it too risky?*



ven said:


> Protection adds around 3-4mm on the 18650 cells,not sure with 10440,mishaps wise yes.



I believe that the smallest protections are close to 2mm thickness, but I do not have any hard data.


----------



## ven

*Re: Li-ion EDC - is it too risky?*

14500 protected




....Dont think i have any 14440


----------



## ven

*Re: Li-ion EDC - is it too risky?*



murrydan said:


> So, if a protected 10440 is too long I should still be ok unprotected.. As long as I play it smart.
> 
> Most mishaps from user error? (over charge - over discharge)



Going to thow this into the mix efest IMR 16340 cell in a d25cvn (vn=vinh modded) lovely ti light,small,de-domed

Size wise















IMR is a safer li-ion chemistry,also its small as can see,so makes an ideal edc.........only a thought..............nothing more


----------



## HKJ

*Re: Li-ion EDC - is it too risky?*



ven said:


> IMR is a safer li-ion chemistry



The safer part can be discussed. It need a higher temperature to ignite, but it can usual deliver more current, making it easier to reach that temperature.
Also, many IMR cells are missing the HRL.
I.e. the final decision about what is safest is more depends on construction details, than on chemistry.


----------



## ven

*Re: Li-ion EDC - is it too risky?*



HKJ said:


> The safer part can be discussed. It need a higher temperature to ignite, but it can usual deliver more current, making it easier to reach that temperature.
> Also, many IMR cells are missing the HRL.
> I.e. the final decision about what is safest is more depends on construction details, than on chemistry.




Good point:bow::thumbsup:


----------



## mcnair55

*Re: Li-ion EDC - is it too risky?*

I see we are onto the bogey man scare stories once again,what a load of nonsense.If you can use the cells in question just do it.I have had mobile phones since they were the size of a house brick and never had issues with batteries apart from there wearing out due to mega usage.


----------



## murrydan

*Re: Li-ion EDC - is it too risky?*



mcnair55 said:


> I see we are onto the bogey man scare stories once again,what a load of nonsense.If you can use the cells in question just do it.I have had mobile phones since they were the size of a house brick and never had issues with batteries apart from there wearing out due to mega usage.



Yeah, starting to realize that.. Thanks to everyone for the helpful information.


----------



## Pellidon

*Re: Li-ion EDC - is it too risky?*

I carried a Nuwaii Q3 for years with a no-name protected cell. My charger was one of the old ones that charged the 123 size sideways compared to the 18650's it could charge. I would still have it if someone had not stolen it out of my car. I finally switched to an EagleTac 25 clicky in AA since I can get small and bright now. I was never worried about a single LI-Ion cell light for EDC. Double cell lights were too big for my pockets.


----------



## HKJ

*Re: Li-ion EDC - is it too risky?*



mcnair55 said:


> I have had mobile phones since they were the size of a house brick and never had issues with batteries apart from there wearing out due to mega usage.



That is the same for 99.99xxxx% of the mobile phone users and likewise for laptop users, but there has been a few cases of exploding phones and computers.
These cases has often bee taken very serious, i.e. product recall and analysis of why it happens. Sadly this information is seldom published.
Some reason I have seen is impurities in the isolation between the two electrodes in the battery, leading to an internal short. Then the temperature raises above the ignition point and ....


----------



## ven

*Re: Li-ion EDC - is it too risky?*

No bogey man stories here,actually have said in some threads that you are at more risk going up the stairs or to be struck by lightning....


For me its awareness,you may be surprised how many peeps actaully leave li-ion cheap fire cells on charge over night.Also on cheap chargers so over charge..........


I would rather people be aware the safety side,using known brands and chargers that stop trickling over 4.2v and potential of fires

So my recommendation is simple,decent charger thats been reviewed,stops at around 4.2v or less,decent cells,not left unattended............thats it.

Especially if someone has opened a thread about "is it too risky" when the answer is NO it is not.Just topic has gone off a little but interesting finding out further measures in place for future cells,after all if there was no need why bother.............

Just my opinion,i am certainly no nerd,i enjoy my lights,dont break into a sweat when on charge,never had an issue and charge on a daily basis 7 days a week,now for probably an easy 4 maybe up to 5yrs...........could be longer still as not kept a record.

Phones have built in protection,as with chargers,some cells dont,nore do lights,never heard of a phone exploding,but i have lights.Agree more than likely down to owner incompetent and equipment failure but it does happen...........always will,its about educating to limit or best case prevent issues,especially to newbies who are using 3x li-ion cells stacked in crapy cheap chinese lights .Of which would know no different unless peeps take time to explain issues,they are not common and educate on how to avoid/limit these from occurring.........
No harm in education..........
My opinion again,and i will stick with it  just no need for OTT info as can come across off putting:thumbsup:


----------



## ven

*Re: Li-ion EDC - is it too risky?*



HKJ said:


> That is the same for 99.99xxxx% of the mobile phone users and likewise for laptop users, but there has been a few cases of exploding phones and computers.
> These cases has often bee taken very serious, i.e. product recall and analysis of why it happens. Sadly this information is seldom published.
> 
> That could be why i have not heard of any issue,same as the bmw d engine that catches fire............yes correct,kept quite with that one,i only know as someone's 525d caught fire and burnt out.Not the 1st app,car covered up in corner of bmw garage,app a turbo issue and bmw at time had not got to the bottom of the issue............not exactly good publicity.!!!!
> 
> Then the bmw mini fires,not to mention the li-ion battery issue on planes.............(cockpit not cargo)


----------



## CyclingSalmon14

*Re: Li-ion EDC - is it too risky?*



murrydan said:


> Thanks for the reply.
> 
> I have read that the protected 10440s are too long to fit in the Eiger (2mm longer), so I think they are a no-go.. If not *****fire, which brand would you recommend?



WHAT....Protected 10440 cells even exsits? I cant even find decent unprotected cells!!!! only **** Fire ones, just want a good unprotected one or protected.....for my Olight I3S its a bit crappy on Nimh IMO.

I have yet to see any relible 10440 cells, only seen good 14500 / RCR123a / 16340 or above, please if you know something I dont please share!!!


----------



## murrydan

*Re: Li-ion EDC - is it too risky?*



CyclingSalmon14 said:


> WHAT....Protected 10440 cells even exsits? I cant even find decent unprotected cells!!!! only **** Fire ones, just want a good unprotected one or protected.....for my Olight I3S its a bit crappy on Nimh IMO.
> 
> I have yet to see any relible 10440 cells, only seen good 14500 / RCR123a / 16340 or above, please if you know something I dont please share!!!



Yeah, Trustfire makes some protected ones.. But you are right, all I can find are ****fire batteries. I have heard of some mythical ones by "AW", but they seem to be out of stock everywhere.


----------



## CyclingSalmon14

*Re: Li-ion EDC - is it too risky?*

"No surrpise, 10440 lights are not really popular, most of that size are low output, so Nimh do fine, anything brighter tends to over heat, only really worth it on 14500 and above, but a I3S on 10440 is funny for gigles but you it gets hot after 30 seconds XD from what have read so low demand, = near zero production, Might grab some Trustfires and just keep eyes on them and just use it for show and Nimh for actualy EDC use...but as said its not a practical light in direct drive, but seeing something that small and bright always gets wows, hopeing to ahcive the same sort of WOW from the D25CVn I have in shipping atm.


----------



## ven

*Re: Li-ion EDC - is it too risky?*

As long as charged in a decent charger,and not 1,000,000mah,a reputable seller than should be fine.I have said before i have a few fire cells,ones with actual fire on sides are quite fine,others not so.

Juts treat with care,simple as that,not as if your using 4 x fire cells

Personally i would get these,just put this in ant on bay of e 181263823016


----------



## ven

*Re: Li-ion EDC - is it too risky?*



ven said:


> As long as charged in a decent charger,and not 1,000,000mah,a reputable seller than should be fine.I have said before i have a few fire cells,ones with actual fire on sides are quite fine,others not so.
> 
> Juts treat with care,simple as that,not as if your using 4 x fire cells
> 
> Personally i would get these,just put this in ant on bay of e 181263823016



Edit-thats the shop i use for high drain cells


----------



## murrydan

*Re: Li-ion EDC - is it too risky?*



ven said:


> As long as charged in a decent charger,and not 1,000,000mah,a reputable seller than should be fine.I have said before i have a few fire cells,ones with actual fire on sides are quite fine,others not so.
> 
> Juts treat with care,simple as that,not as if your using 4 x fire cells
> 
> Personally i would get these,just put this in ant on bay of e 181263823016



Thanks.. Unfortunately, they do not ship to the US. 

All of you guys have really helped me overcome my paranoia regarding these cells.


----------



## mcnair55

*Re: Li-ion EDC - is it too risky?*



murrydan said:


> Thanks.. Unfortunately, they do not ship to the US.
> 
> All of you guys have really helped me overcome my paranoia regarding these cells.



Just enjoy your lights and common sense is your best friend.


----------



## LightWalker

*Re: Li-ion EDC - is it too risky?*

I have been edcing a light with 2x AW RCR123's for months. I have carried a light with single AW 17670 for years and I carry a light with a single Trustfire RCR123, all protected with no issues. Back in the day (2007) I carried a light with an unprotected Ultrafire 10440 and had no issues.

I do not over discharge my cells, I top them off before they get very low and I check the voltage often. I also monitor my charger and remove the cells as soon as charging is completed.


----------



## ven

*Re: Li-ion EDC - is it too risky?*



mcnair55 said:


> Just enjoy your lights and common sense is your best friend.




+1 To that mr mcnair55,

common sense is all thats required,little research and the right brand/make and ENJOY!!!


----------



## ven

*Re: Li-ion EDC - is it too risky?*



murrydan said:


> Thanks.. Unfortunately, they do not ship to the US.
> 
> They do from alibaba
> just put in
> **Efest 10440 AAA 350mAh * on google and options will appear before you*


----------



## asimpson

*Re: Li-ion EDC - is it too risky?*



ven said:


> murrydan said:
> 
> 
> 
> Thanks.. Unfortunately, they do not ship to the US.
> 
> They do from alibaba
> just put in
> **Efest 10440 AAA 350mAh * on google and options will appear before you*
> 
> 
> 
> 
> Is Alaibaba trustworthy? Been tempted a few times but never sure what I'm going to be getting.
Click to expand...


----------



## Goredoth

Thanks for writing this guide, never realised how much there was to properly caring for Li-ion batteries and also helped me find a reliable charger the Pila.

Much appreciated!


----------



## ven

*Re: Li-ion EDC - is it too risky?*

@asimpson-Have used them once or twice in past,issue free,seems like just a huge online shop with different sellers,like an ebay without bidding.

They have feedback,so go from there,sure protection too,i tend to use banggood for most bits,others i just search for and take a chance.......within reason obv,i am not going to spend $400 on a shop i dont know.........


----------



## thedoc007

*Re: Li-ion EDC - is it too risky?*



HKJ said:


> I did also do a test myself (By accident): In a usb power box with four batteries in parallel I put in four 3100mAh unprotected cells, but turned one of the cells backward. It only took a few second *before I was clued in to my mistake: springs are not supposed to glow.*



I laughed when I read this. Wonderfully understated.


----------



## Joys_R_us

*MH370 had Lithium cells as cargo on board*

A few months ago I read in this (?) forum that only Malaysia Airlines was transporting lithium cells sold by Chinese and Hongkong retailers.

if the loss of the airplane MH370 is really a result of igniting lithium cells it will be very difficult in future to buy them overseas (unless sent via ship)....


----------



## ven

*Re: MH370 had Lithium cells as cargo on board*



Joys_R_us said:


> A few months ago I read in this (?) forum that only Malaysia Airlines was transporting lithium cells sold by Chinese and Hongkong retailers.
> 
> if the loss of the airplane MH370 is really a result of igniting lithium cells it will be very difficult in future to buy them overseas (unless sent via ship)....



Without derailing as already another thread,they have a limited time to find the black box,iirc 2 weeks or 3 weeks then back up is lost so wont know.I would say that reason would be very remote tbh as the plane went well out of its way and signals would have been given if a fire,if was the case then why fly possibly 7hrs in another direction before.......just thoughts:thumbsup:


----------



## mcnair55

*Re: MH370 had Lithium cells as cargo on board*



Joys_R_us said:


> A few months ago I read in this (?) forum that only Malaysia Airlines was transporting lithium cells sold by Chinese and Hongkong retailers.
> 
> if the loss of the airplane MH370 is really a result of igniting lithium cells it will be very difficult in future to buy them overseas (unless sent via ship)....




Where did you read that?

ps I use to live in Berlin in the mid 2000,s


----------



## Gloh

*Re: MH370 had Lithium cells as cargo on board*

Thank you for compiling such a useful thread! It'll definitely be something I refer to often in the future.

I just have a question (open to anyone with knowledge in this area). I'm new to 18650's and recently got my hands on some Nitecore 3100mAh batteries.
Firstly, are they any good?
Secondly, it says 3.7V on the battery. I tested them with a voltmeter and sure enough they were 3.7V out of the packet, so I've been using them like that since. 
However, it says on the post that you can charge up to 4.2V? So should I charge them till 4.2V or till 3.7V? I'm very confused.

Thank you!


----------



## ven

*Re: MH370 had Lithium cells as cargo on board*



Gloh said:


> Thank you for compiling such a useful thread! It'll definitely be something I refer to often in the future.
> 
> I just have a question (open to anyone with knowledge in this area). I'm new to 18650's and recently got my hands on some Nitecore 3100mAh batteries.
> Firstly, are they any good?
> Secondly, it says 3.7V on the battery. I tested them with a voltmeter and sure enough they were 3.7V out of the packet, so I've been using them like that since.
> However, it says on the post that you can charge up to 4.2V? So should I charge them till 4.2V or till 3.7V? I'm very confused.
> 
> Thank you!




It can be a little confusing at 1st,yes they should come at 3.7v which is around 40% charge so ideally charge straight away.A good charger will charge to 4.2v (+ or - 0.1)

This is 100% of a 3.7v or rather 4.2v cell.

So yes charge to 4.2v,good practice is to top off cells so after some use ,top them back up to 4.2v rather than run them down to bellow 3.7 or even 3.5v.
Topping off is not classed as a full recharge cycle.So example,topping off from 3.9v to 4.2 several times =1 charge cycle...........usually 18650 cells have a 500 cycle life(approx of course)

Use of MM is a good idea also as can keep an eye on your cell so:thumbsup:

Yes the nitecore 3100mah cell is good,but not best value as the cost is more for the brand (nitecore) as with many branded cells.

Look into protected KeepPower/Xtar/panasonic(green cells) for better value i could go on with lots of brands...........just make sure the are not ultra or anything fire cells.


----------



## Gloh

*Re: MH370 had Lithium cells as cargo on board*

Thanks for the reply mate. I love that there's such a huge database of users that responses come within minutes.

Ah well my charger hasn't arrived in the mail yet, and my guesses will be that it arrives next week. 
Is it a bad idea to be using the battery now straight out of the packet? I've had my first real torch for nearly a week with no batteries so I was dying to try it out.

I'm still confused as to why they write 3.7V instead of 4.2V?


----------



## ven

*Re: MH370 had Lithium cells as cargo on board*



Gloh said:


> Thanks for the reply mate. I love that there's such a huge database of users that responses come within minutes.
> 
> Ah well my charger hasn't arrived in the mail yet, and my guesses will be that it arrives next week.
> Is it a bad idea to be using the battery now straight out of the packet? I've had my first real torch for nearly a week with no batteries so I was dying to try it out.
> 
> I'm still confused as to why they write 3.7V instead of 4.2V?




Your welcome,i have had lots of help,its a great forum and i learn more every visit!!! full of great peeps,very helpful and as you say always someone to answer.........guess the experts are in bed :laughing:

They are 3.7v as said at 40% charge,that is the ideal storage charge.Its not good practice to store cells long term at 100%(4.2v) ie longer than a month or 2........so they should! come at around 3.7v

Its fine to try/test but would not be using it for an hour or 2 for example as it will drop right down,not sure when the pcb(protection) on that cell will work,but say its 2.5v it not good for the cell.

So test it,then charge it to 4.2v and enjoy..........after use,maybe an hour or so,top off,may only take an hour charge.Charging from 3.2v or 3.5v will or could take 5hrs+ depending on charger .

What charger have you gone for?
I have the nitecore i4 and is a good overall charger for the money,also the xtar wp6 again a good charger but not the best out there.

Some new Xtar chargers are very good,check on here the reviews if not done already,also do a little reading up on 18650 cells.No need to spend days,just get an insight into the safety side(dont leave untended or on over night charging ,dont use cheap branded *****fire cells for example ) not saying all are bad,just a 50/50 chance of them being.This also depends on the retailer where purchased,so use reputable sellers recommended on here and enjoy safe 18650 use


----------



## Gloh

*Re: MH370 had Lithium cells as cargo on board*

Yeah I'll keep an eye on the Voltage. As the post suggest, don't let it drop to below 3.2V so I'll definitely be checking it regularly with MM.

I have been researching extensively on the use of 18650's. Unfortunately, I didn't invest in any of the xtars or nitecore branded charges and just went for a generic one off DealExtreme which had a lot of positive reviews (100+). That being said, I know many people on this forum stress the importance of good chargers but I will definitely be keeping an eye on both the temperature and the voltage of the battery when charging. 

Is there a way to tell if the protection has been set off?


----------



## ven

*Re: MH370 had Lithium cells as cargo on board*

If you can invest in a better charger,i presume a cheap one from DX and some do not stop charging so trickle after the 4.2v.

If removed when turns green and test volts,close eye kept on the cell voltage then you will be ok.

For under $20 or around £12 you can buy an i4(just an example as lots out there) and this has 4 bays(future proofs it for more lights/cells.......well in the future)

So do as you say,keep an eye on it and see if it does stop charging at 4.2v or 4.19 for example,if it continues up to 4.25 then would presume its going to keep charging...
2 options,if using remove as soon as it shows its charged(usually led light fully on) or invest(not much money tbh) in a recommended charger.Check reviews on here for those

If pcb has "tripped" then 0v ,over charging,over discharging will trip it.

Have a read here
http://www.candlepowerforums.com/vb/showthread.php?341777-What-exactly-trips-a-PCB


----------



## Gloh

Thanks again ven.
Yeah Perhaps if I get more serious into the whole flashlight collecting thing, I might invest in a better charger for a peace of mind. 
For now, I think I can manage with the DX one.
I'm not keen to try out the 4.2+ trickle charge. I'd rather not trip out the PCB.

And I never knew they could reset! Always thought they were a one off save-your-life thing and after that you were on your own haha. Kind of like an airbag or parachute.


----------



## ven

As long as not left on,check volts after charge and take from there


----------



## TSellers

> Originally Posted by *Joys_R_us*
> 
> _A few months ago I read in this (?) forum that only Malaysia Airlines was transporting lithium cells sold by Chinese and Hongkong retailers.
> 
> if the loss of the airplane MH370 is really a result of igniting lithium cells it will be very difficult in future to buy them overseas (unless sent via ship)....
> 
> _
> 
> 
> Where did you read that?



That shipping requirement still seems to be correct. Malaysia Post is one that still seems to takes bateries, and I think we also got a shipment via Sweden Post. Most of the Chinese sellers list on their websites which postal methods you can get batteries sent by, and those are commonly mentioned. Knives are now also in the same boat. 

I recently had a shipment of VHF radios refused by DHL in CHina because they contained the standard sealed Li-Ion battery packs that are used on VHF radios. Then a week later they changed their policy and took them.


----------



## mcnair55

TSellers said:


> That shipping requirement still seems to be correct. Malaysia Post is one that still seems to takes bateries, and I think we also got a shipment via Sweden Post. Most of the Chinese sellers list on their websites which postal methods you can get batteries sent by, and those are commonly mentioned. Knives are now also in the same boat.
> 
> I recently had a shipment of VHF radios refused by DHL in CHina because they contained the standard sealed Li-Ion battery packs that are used on VHF radios. Then a week later they changed their policy and took them.



No surprise as DHL is wholly owned by the German Post Office and as you may know the eco friendly Greens are very successful in German politics.Our company have had issues with certain products for delivery.


----------



## TSellers

> No surprise as DHL is wholly owned by the German Post Office and as you may know the eco friendly Greens are very successful in German politics.Our company have had issues with certain products for delivery.



No I didn't know that, that's interesting. They sure seem to waffle depending on what week or day it is. When that happened, the manufacturer said they could still send UPS for $25.00 less, which I did not want to happen under any circumstances because we all know that that cheap UPS shipment doubles in cost with the additonal fees they collect on your end. I tried to get them to send EMS, but for some reason the shipping cost was going to be $750.00, for the same size and weight similar shipment that actuallly contained 18650 cells that EMS took late in 2013 for $250.00 (after DHL had refused that one becuase of the cells as well).

I was horrified last year when I ordered some NCR18650B cells from a popular Chinese supplier and they arrived loose in a bubble wrap envelope, two of them had simply fallen out of the plastic wrap they had put them in. I sent them an email right away with pictures and they said they'd improve their shipping of cells. So a few weeks later I bought some 14550 cells, and they arrived the same way. So I will no longer deal with them, and I warned others in the other forum where you are allowed to post vendor names about the dangers of buying cells from that particular supplier as well. It looks like the high increase of demand for these cells created by vaping products is a big contributing factor for them becoming a popular item with irresponsible sellers, which forced the Chinese authorities to take action, it's just a bummer that it now adversly affects the sealed battery packs such as those for phones, computers, and radios that previously shipped with no real problems.


----------



## Gloh

ven said:


> As long as not left on,check volts after charge and take from there



Well I finally got my charger yesterday and began the lengthy procedure of charging my 18650s.
I had to stop it last night before I went to bed and it read ~3.9v on my MM.
Began charging again this morning and checked up on it. Measured it and it said 4.3v.

Now the light is suppose to be green when it's charged, BUT I'm sure it was red.
BUT I'm also colorblind. So... Lights useless to me anyway...


----------



## STORMINORMAN

So... Using two protected 3.6v Li-Ion 17500 batteries stacked in a SureFire 3G (or, for another example, a SolarPower L2 Series light with a 1 X 123a Extender) that has a P60L (3-9v led) drop-in is a safe rechargeable alternative to using 3 X primary 123a batteries?

Thanks!


----------



## STORMINORMAN

STORMINORMAN said:


> So... Using two protected 3.6v Li-Ion 17500 batteries stacked in a SureFire 3G (or, for another example, a SolarPower L2 Series light with a 1 X 123a Extender) that has a P60L (3-9v led) drop-in is a safe rechargeable alternative to using 3 X primary 123a batteries?
> 
> Thanks!



THANKS to vicv who answered a similar question on another post. I apparently misinterpreted the common manufacturer's warnings about using multiple (i.e. "stacked") protected li-Ion cells vs. "pack building".


----------



## Pravda45

Hi I am in South Africa and want to buy an Olight M21xl2 or M22, the website selling the Olights are selling only the 
Cytac CY015 Universal Battery Charger with 220V Adapter & 12V Cigarette Lighter Adapter http://www.iwarehouse.co.za/auto-bi...h-220v-adapter-12v-cigarette-lighter-adapter/
and
Cytac 3.7 Li - ion 18650 2600 mAh with (PCB) or 2900 mAh http://www.iwarehouse.co.za/electronics/batteries-chargers/cytac-3-7-li-ion-18650-2600-mah-with-pcb/ 

Can anyone tell me if these batteries and charger are ok or should I look around for something else? I haven't seen them mentioned on the thread. These are already stretching my budget and I am not really able to spend more on a battery and charger. I would like to know if these are decent quality with regards to lifespan and output and are they SAFE?

I know nothing about these batteries other than what I have read here, I had no idea they were so complex and am more uncertain about the Cytac than ever.

Thanks


----------



## marrandy

I bought a ThruNite TN11S (Approx. 830 lumens $39.95) and a IBC charger and Two AW 18650/34 protected batteries.

The working voltage per the manual is 3V to 12V.

It has Two extra screw on extensions so you can have three different lengths.

It suggests you can use Two, 3=Three or Four CR123A batteries or One or Two 18650 batteries.

After reading this and other threads, I am sticking with One 18650.

I have also read, in several places that 4.2V = 100%, 4.1V = About 90%, 4.0V = 80%.

My new AW 18650 protected batteries are charging to 4.09 and 4.10 respectively.

So this is only about 90% ?

Does anyone get the mythical 4.2V/100% ??

Or is 4.10V more usual ?

Thanks


----------



## HKJ

marrandy said:


> I have also read, in several places that 4.2V = 100%, 4.1V = About 90%, 4.0V = 80%.



That depends on the battery, I decided to test it and made a table with the results:








marrandy said:


> My new AW 18650 protected batteries are charging to 4.09 and 4.10 respectively.
> 
> So this is only about 90% ?



It is not full capacity and it is fairly low for new batteries. 



marrandy said:


> Does anyone get the mythical 4.2V/100% ??
> 
> Or is 4.10V more usual ?



I would usual expect somewhere between 4.15 and 4.20 volt, depending on charger and age of battery. Old and worn out batteries will be lower.


----------



## thedoc007

marrandy said:


> Does anyone get the mythical 4.2V/100% ??
> 
> Or is 4.10V more usual ?



You should definitely get closer than that. Coming off my charger, cells are usually 4.17 to 4.19 volts. You usually don't want to see 4.2 volts, because the voltage is always a little higher when charging...so if you see 4.2 after charging, it was charging to ABOVE 4.2 volts. 

I would test your charger with other cells. If they charge normally maybe you got some bad cells. If the other cells don't charge normally, time to get a new charger. Even though it may be fine (other than the capacity loss), once a charger is out of spec, it is time to recycle it. Don't wait for something to go wrong which could be more problematic.


----------



## marrandy

The other possibility, is that my DVM isn't as accurate as it should be.

The other batteries are pretty much the same. I'll try and check the DVM against someone else's.

Thanks for the responses.


----------



## ven

Gloh said:


> Well I finally got my charger yesterday and began the lengthy procedure of charging my 18650s.
> I had to stop it last night before I went to bed and it read ~3.9v on my MM.
> Began charging again this morning and checked up on it. Measured it and it said 4.3v.
> 
> Now the light is suppose to be green when it's charged, BUT I'm sure it was red.
> BUT I'm also colorblind. So... Lights useless to me anyway...



At what time did you check the V,was it charging or after you removed the cell from charger. For a more accurate reading after charging,leave the cell for 10 minutes or so and check V. If cell is not being used,re-check again next day and see if charge is held and V is the same or within 0.01V.

Obv the MM may read out but still i am suspicious of your charger being honest. Some cheap chargers will carry on trickle charging after it should terminate and 4.3v is too high imo. 

My advice if you can would be to invest in a better charger than the very cheap ones from DX.

No need to spend lots of money when i say better charger,for example an nitecore i2 or i4 can be had for under $20.These have bars that flash and go solid as it charges,once charged all are light perminant so any issues regarding colours is negated.

Some xtar charger options too which have great reviews on here(worth checking out). If you have a single cell light the sp1 will be fine(but an led again),can be had for around $20 and has 3 charge options along with 3 cell options . 3.2v/3.6v(this for your 18650 cell to charge to 4.2v) /3.8v(for 4.35v cells )
sp1



Above is just an example,the vp2 is more expensive but has actual voltage read outs and 2 charge bays with various options for cell/types so a good investment long term.This you will see the bars full and read out once charge finished.


----------



## marrandy

thedoc007 said:


> If the other cells don't charge normally, time to get a new charger.




It is a brand new PLAIBC Pila IBC Charger. The batteries are new too. Bought from lighthound in TX.

I received both charger and batteries on Thursday the 29th May 2014.


----------



## Richwouldnt

With all of the warnings about not mistreating lithium ion batteries I wonder about two of my recently bought name brand flashlights. First is a Thrunite TN32 which as received has a battery holder that will not accept 90% of all commonly available protected 18650 batteries. Maximum battery length that will fit it as received is about 68.3 to 68.4mm and most protected 18650 batteries are 68.8mm long or longer. I have ended up disassembling it and adding shims at both ends of the four through shafts to increase battery holding capacity to 70+mm length batteries as I did not want to put excessive force on battery ends while installing or removing them from the holder and risk damaging protection circuit boards.. NOTHING in the instructions about any limitations on useable battery length.

The second light is a Jetbeam RRT-3, also a recent purchase. It's problem is with battery diameter. Orbtronic on their web site specifically notes that their 3400 mAh batteries may not fit in the RRT-3. Their 3100 mAh cells do fit (barely). The light body is bored small enough so that many 18650 cells are just a hair too large in diameter to fit in the battery holder and then have it fit into the flashlight without force being used which appears to me as having a potential for damaging the battery shrink wrap and thus causing a short. NOT GOOD. IMO the light body should be bored large enough to accept the battery carrier with all major brands of cells with no insertion force required. Otherwise it is a disaster waiting to happen and very stupid engineering and/or quality control.

The original author of this thread warned about the danger of applying force to lithium ion cells and yet these lights, as delivered, practically invite such behavior with the associated risks of problems and both of these are major light brands, at least in the USA market. Maybe not in Fenix or Olight popularity class but still well known brands. Maybe though why it appears that Battery Junction is apparently discontinuing carrying both brands. At least they were having a clearance sale on Jetbeams until very recently and when I emailed them on the availability of the ThruNite TN32 their answering email stated that they did not carry Thrunite even though their web site listed 4 models as still in stock.


----------



## Zorzi

I agree it is potentially dangerous when some lights can barely accept some common li-ion cells in the market, but I think both the light AND the cell manufacturers might design their products in conformity to the standards (afterall, that is why they exist). In this sense, my question is, which product is out of specifications, your lights or your batteries? Cause I suppose this the cell manufacturers most times exceed the standard cell heigh and sometimes diameters to increase the energy content of the cells. 18650 cells should have 65mm height, as far as I know.


----------



## ven

Yes all 18650 are 18mm by 65mm long,but then the PCB and wrap changes this dependent on manufacturer.

So you can have an 18.4mm by 69.4mm (just an example)

Eagletac for example are one of the shortest protected cells out there as far as i am aware:thumbsup:

Lot of the pany cells vary due to who fit the PCB etc

Edit- 2 protected cells,Xtar and pany,can see a difference in height









Unprotected and protected (PCB on bottom)




iirc all pany cells are flat top ,button tops are added after .

The PCB can range up to 4mm+ added to length depending on brand.

Agree though,Thrnuite should make their carriers more universal towards cell lengths.
Fenix have with their tk carriers
Here are one of the longer cells (pany) and sanyo




No reason why Thrunite cant make the carrier fit longer cells.............


----------



## Zorzi

Maybe the manufacturers should agree in a new standard for protected cells, something like 18800, for example..


----------



## ven

Zorzi said:


> Maybe the manufacturers should agree in a new standard for protected cells, something like 18800, for example..



Iirc the longest are around 70.4 but stand to be corrected ,80mm long would change light length and be difficult for example on shorter cells.Say for example you had a 65mm cell be it unprotected or IMR and an 80mm cell.............thats a difference of 15mm so its a huge ask in those parameters to hold a cell secure.

Ideally 65 to 71.4mm would be ideal as i dont know of any cells over 70.4mm long(i await to be enlightened on that,if so it will be 0.1 or 0.2mm):thumbsup: so around 5.4/5.5mm of flexibility .

The spring would have to be flexible to allow to compress without damaging the longest cell,but still stiff enough to support shorter cells without them feeling loose in the light.


----------



## Zorzi

Right, Ven, I forgot that the lights still have to be compatible with the shorter unprotected cells


----------



## ven

My F8 only likes unprotected cells,tbh they are fine in single cell lights anyway.Protected are advised for newbies to the world of Li ion but common sense is all thats needed along with a little understanding along with a decent charger(no point in good cells and a crap ******fire charger imo)

Multi cell lights its recommended to use protected of which i do in my tk75vn and tk61vn(just to name some)
I have used unprotected in my tn35vn




But now use IMR 2100 30A KeepPowers 




At some stage i will get some pany PFs as they offer a good all round alternative at 2900mah and 10A rating and good value too.


----------



## Zorzi

I will experiment first with single cell LiIon lights, but anyway, I will start with protected cells as I'm a newbie and a nitecore i2 charger.


----------



## ven

Zorzi said:


> I will experiment first with single cell LiIon lights, but anyway, I will start with protected cells as I'm a newbie and a nitecore i2 charger.



:thumbsup: 

If you have not got already, a "cheap" multi meter is a good idea,and good enough for keeping an eye on things. Every so often i check the V off the charger after 10/20 minutes rest. Also on some older cells to make sure holding charge. Not something i use daily ,but every few weeks/month. 

Not a must,just useful to have and may show something up, along with easier diagnosis of any potential issues down the line


----------



## Geese

I am new at this but have been reading this forum for a long time. I finally bought a NiteCore TM11, Nitecore i4 v2 Charger and 4 XTAR 18650 3400mAh cells. I have read the review by selfbuilt on the charger, read the reviews and tests of the batteries, the review of the TM11 and many other threads. It wasn't until today that I read this particular thread so I was a bit naive about li-on cells. With my combination of flashlight/batteries/charger, is it possible to discharge too quickly or charge too quickly? I am going on a 4 week trip involving lots of flights and trekking. I expect it too be hot an humid for much of the trip, would it be better to choose another type of cell? Are the CR123 or RCR123 cells any less volatile? Will I have trouble carrying this light and cells as carry on luggage? Will altitude affect any of the temperature or operational tolerances? 

I am very sorry if some or all of this has been answered but I am looking for reassurance/advice as after reading a significant amount I am still uncertain.

Geese


----------



## thedoc007

If you use the cells in the TM11, there is no chance you can discharge them too quickly. Nor is there any chance the Nitecore i4 will charge them too fast...it is in fact a fairly slow charger, which is easy on the cells.

If you carry-on your light, they may want to take a second look at it. I carried my TM26 on, and they sent it through the X-ray machine twice, then swabbed it for chemical residue, then made me turn it on. All told it delayed me by maybe two minutes, and I was on my way. Not banned, just an item that they aren't used to seeing. On my way back, they didn't look twice, just sent me on my way. In fact, due to the TSA rules, it is actually BETTER to carry-on anything that uses lithium ion cells.

There is no reason to be afraid of a little heat or humidity. First of all, when sealed, the light is airtight/watertight. So it doesn't matter much what is going on outside. The only substantial difference is that in warmer environments, it will heat up faster. The TM11 has temperature-controlled stepdown, though, so again, there is very little chance you will have any problem.

You made good choices...relax and enjoy your new light!

Edit: Those Xtar cells are on the long side...and there is some variation in the TM11's ability to accept long cells. IF for any reason those cells are too tight, don't force it. You may damage the springs. Hopefully it won't be a problem, but be careful.


----------



## ven

As above,just have the train of thought when using the light,if it starts to get quite warm to hold,maybe 5 or so seconds then knock it down a level if the tm11 has not,or turn off to cool.No matter what light i use,be it modded or not,thermal or timed i dont rely on it.I always go off the temp of the light in hand.......

I have the tm15,i tested it and it would happily run to a point i was swapping hands every few seconds as the heat must have been approaching 60oC(guesstimate but hot cuppa kind of temp).This was just a test,in this test is did knock it down at a couple of points,if may have confused the thermal step down,or maybe it would have done it soon...........dont know. But best judgement is you imo 

And as said enjoy,i am a fan of the tm series,the tm15 just pipped it for me being a little more throwy and ability to charge cells in house. However the smaller size of the tm11 made it a very very close call!!!!

Congrats,you have a good set up there


----------



## Geese

Thank you both for the replies. I am glad to hear it. I hope that it lasts me a while. 

Geese


----------



## LlF

how good/bad are the 2Ah 18650s inside power tool's battery pack? assuming they are in good condition.
is 2000 mAh considered low for flashlight use?


----------



## thedoc007

3600mAh is the highest available right now, 3400s are quite common. That said, there is nothing wrong with 2000mAh cells. Obviously they won't give you the same runtime, but modern LEDs are so efficient I think it isn't THAT big of an issue. You'll still get hours and hours of runtime at most levels.


----------



## tyxxvxl

Hey guys. Newb here. Im sure you guys get tired of answering the same questions. So I bought a fenix PD35 and a Tenergy TN270 charger with one Tenergy 18650 cell. After reading through this thread Im kinda worried now ha ha. Is this set up going to be ok? I have the battery on the charger now and I keep checking it about every 15 minutes 
Thanks
Ty


----------



## SimonSolar2C

Standard Charging of LiIon cells to maximise capacity
Else where in ths thread it states maximum charge is 4.2v for a single LiIon cell.
However they can be chareged higher with care.
This information comes direct from the manufacturers of cells we use in our products.

These specifications apply to normal cells used for lights, which behave very differently to cells used in RC models ( they can be discharged at 25C or more, and faster charged also )
This is what a well behaved charger should be doing.
The charging and discharging is always relative to battery capacity, C

*Standard Charge :* Temperature 20±1℃, CC charge at 0.5CmA to 4.25V; turn to CV charge; Terminate charging when the charging current value is less than 0.05CmA. 

*Fast Charge:* Temperature 20±5℃, CC charge at 1.0CmA to 4.25V; turn to CV charge; Terminate charging when the charging current value is less than 0.05CmA.

And so 0.7C as a charge rate, recommended earlier in this thread, is somewhere between a Standard and a Fast charge

*Example:* To get maximum charge into your LiIon battery: 
Battery capacity of 1000mah 
Charge to 4.25 volts at between 500ma and 1000ma
_Then_ you may continue charging at constant 4.25 volts until current drops off to 50ma

Discharging: Maximum discharge is usually 2C ( 2 Amps for approximately half an hour in the previous example )
Most device cut off at 3.0v. It okay to go lower, 2.75v but there is very little usable power this low. Battery damage occurs below 2.0v


----------



## HKJ

SimonSolar2C said:


> *Standard Charge :* Temperature 20±1℃, CC charge at 0.5CmA to 4.25V; turn to CV charge; Terminate charging when the charging current value is less than 0.05CmA.
> 
> *Fast Charge:* Temperature 20±5℃, CC charge at 1.0CmA to 4.25V; turn to CV charge; Terminate charging when the charging current value is less than 0.05CmA.



Have you asked the manufacturer how much lifetime you looses by using 4.25 volt, instead of 4.20 volt?

The values of standard/fast/quick charge/discharge is not the same for all batteries, but varies with the actual chemistry and construction.


----------



## SilverFox

Hello SimonSolar2C,

Actually the manufacturers specify charging to 4.2 volts with a tolerance of + or - 0.05 volts. You can misconstrue that to your idea of a charging specification but it is not in the best interest of the battery you are charging. Life cycle is greatly reduced to 10 - 15 cycles on the cells that I tried "overcharging."

Tom


----------



## Gauss163

@Tom Where can I learn more about your overcharging experiments?


----------



## SilverFox

Hello Gauss163,

About 9 years ago we did some exploration...here. We know a lot more now and I don't recommend duplicating these experiments. 

Tom


----------



## eklogite

Hello every body.
This is a great post, I learned a lot about Li-Ion batteries and how to treat them, but I have a question.

In my garden, I am thinking to use some 18650 batteries which I purchased last year.
They were all stored for long time and not being used.
I checked their voltage, few of them show 3.7- 3.8 volts and others show some thing like 2 - 3 volts...
Brand is Ultrafire (red) cells claimed to be 3000Ah but I'm sure they are not.

I want to use them to light a small building with 3.6 Volt led chips.
I am going to use some thing like 6 of these cells in parallel, but there is no electricity here to charge them.
I have a small 4.5 volt 90mA solar charger available to charge the batteries, does it cause an explosion?
We have a pretty good sunlight here from 6 to 19 right now so they will get charged at least 8 hours of solar charge...

Thank you very much.
Eklogite


----------



## realista

i have a doubt. what is the REAL difference between using a non protected vs protected cell in real life usage?
generally you can see the light fading in the flashlight, and you KNOW that this is the low voltage zone of about 3,4...3.0v.(and with latest panasonic 3400mah the SAFE voltage is until 2,5v) so:
A) ONLY A STUPID could arrive to damage an unprotected cell overusing the flashlight.(if the flashlight is a cheap one witch do not stop at a safe voltage)

B) A GOOD quality BRAND flashlight generally have a circuit protection that automatically stops the light in low voltages. so your unprotected cells are SAFE. 

now, i speak about what i know about DISADVANTAGES to have a protected one cell.
1) it is longer. you could have proplem with some power bank usb or some flashlight.
2)they cost a little more
3) is it true that the circuit does have a "little" current draining? i hope it is really little, smaller that the autodischarge rate of the own cell.


----------



## HKJ

realista said:


> i have a doubt. what is the REAL difference between using a non protected vs protected cell in real life usage?
> generally you can see the light fading in the flashlight, and you KNOW that this is the low voltage zone of about 3,4...3.0v.(and with latest panasonic 3400mah the SAFE voltage is until 2,5v) so:
> A) ONLY A STUPID could arrive to damage an unprotected cell overusing the flashlight.(if the flashlight is a cheap one witch do not stop at a safe voltage)
> 
> B) A GOOD quality BRAND flashlight generally have a circuit protection that automatically stops the light in low voltages. so your unprotected cells are SAFE.




This is usual correct for lights that can use one 18650 or two CR123 batteries.
But not for lights with multiple LiIon cells in series or for lights that can use a AA, CR123 and LiIon cell




realista said:


> 3) is it true that the circuit does have a "little" current draining? i hope it is really little, smaller that the autodischarge rate of the own cell.



The protection circuit will drain a little current, but it is very low, it would need more than 10 years to drain the cell.


----------



## realista

HKJ said:


> This is usual correct for lights that can use one 18650 or two CR123 batteries.
> But not for lights with multiple LiIon cells in series or for lights that can use a AA, CR123 and LiIon cell


excuse me, but what is the difference between a 18650 and a cr123 and a LiIon? (the 18650 is not a Liion??) i thought that everyone liIon at 3,6v is equiparable to each other.... the only thing which change is the capacity in mah. But if you see the light going down....with a 18650 it is the same with a cr2 or 18500 or cr123. 



PS i need a little explanation, i am just not sure if for cr123 do you mean NON RECHARGEABLES battery or not. i know cr123 is equal to 16340 battery....right? but maybe cr123 is the name of non rechargeable one and 16340 the rech? ------> however speaking in the flashlight contest i think 99,98% of people talk about rechargeables battery.....and never non ones


----------



## HKJ

realista said:


> excuse me, but what is the difference between a 18650 and a cr123 and a LiIon? (the 18650 is not a Liion??) i thought that everyone liIon at 3,6v is equiparable to each other.... the only thing which change is the capacity in mah. But if you see the light going down....with a 18650 it is the same with a cr2 or 18500 or cr123.
> 
> PS i need a little explanation, i am just not sure if for cr123 do you mean NON RECHARGEABLES battery or not. i know cr123 is equal to 16340 battery....right? but maybe cr123 is the name of non rechargeable one and 16340 the rech?) however in the flashlight contest i think 99,98% of people talk about rechargeables battery.....



All batteries named with numbers like 18650, 16340 is assumed to be LiIon here on cpf (The numbers are a size specifications and could also be used on other types of batteries).

CR2, CR123, AA, AAA, C, D are always assumed to be primary batteries, i.e. non rechargeable.

RCR123 or R123 is a rechargeable CR123 battery, we do usual call it a 16340 battery here. 
With LiIon there is more than one chemistry and different voltages, around here we usual talk about cells that can be charger to 4.2 volt and has a nominal voltage of 3.6 to 3.7 volt.

Especially with CR123 here is a lot of confusion with voltage: http://lygte-info.dk/info/CR123A and rechargeable substitutes UK.html


----------



## pokelda2

So i have a ledlenser m8 flashlight and it uses 2 cr123 cells which are a little too expensive for my taste. Is it safe to use 2 3.7 volt 18350 cells in it when regular cr123 cells are only 3 volts?
Also how important are the batteries amps? is that just maximum it can output? or is that how much it out puts?

Also I have some tenergy 18650 batteries and a tenergy 18650 charger that says it has internal pcb protection to prevent overcharge at 4.25 and under charge at 2.5 

Ive left my batteries on the charger for prolonged periods of time before and didnt have a problem
Any one know if this charger is actually any good or am I just lucky my batteries didnt explode?

The one I have is product number 01269-01
looks like this one but might be a different model number
http://www.amazon.com/dp/B004FOUNWW/?tag=cpf0b6-20


----------



## thedoc007

pokelda2 said:


> So i have a ledlenser m8 flashlight and it uses 2 cr123 cells which are a little too expensive for my taste. Is it safe to use 2 3.7 volt 18350 cells in it when regular cr123 cells are only 3 volts?



Easiest way to check that is in the manual. Most lights have a list of supported cells/batteries. It can be a problem to use cells with higher voltage...just depends on the driver, and what range it can accept. 



pokelda2 said:


> Also how important are the batteries amps? is that just maximum it can output? or is that how much it out puts?



Usually if you see an amp rating, it is the max it can support. Again, the individual driver will determine how much current it actually delivers. On many lights, especially single cell ones, IMRs or other high drain cells usually are a little brighter (and boost the current) but it is not usually a huge difference. The exception is direct driver or FET drivers, those typically draw a LOT more amps from IMR.



pokelda2 said:


> Also I have some tenergy 18650 batteries and a tenergy 18650 charger that says it has internal pcb protection to prevent overcharge at 4.25 and under charge at 2.5
> 
> Ive left my batteries on the charger for prolonged periods of time before and didnt have a problem
> Any one know if this charger is actually any good or am I just lucky my batteries didnt explode?



I wouldn't say you were lucky, really, but it isn't a good idea to leave cells on a charger for an extended period. Some chargers trickle charge, and will cook the battery eventually (even if it doesn't vent, will dramatically decrease the lifespan of the cell. And any electronic component can fail, including a protection circuit. Better to avoid depending on a single component if you can help it.


----------



## pokelda2

thedoc007 said:


> Easiest way to check that is in the manual. Most lights have a list of supported cells/batteries. It can be a problem to use cells with higher voltage...just depends on the driver, and what range it can accept.



Unfortunately the manual is rather light on information and even the led lenser site only calls it a "high end power LED"


----------



## pbolomey

Interesting thing I just purchased pair of Ultrafire LC 26650 5800mAh 3.7V batteries, I also purchased a Nitecore D4 Intellicharger Universal Battery Charger, I used that batteries once on my diving torch until the runned out of power.

Now I try to charge them but only one did get recognized and charged the other is completely dead and no volts register on the multimeter.


----------



## thedoc007

pbolomey said:


> Interesting thing I just purchased pair of Ultrafire LC 26650 5800mAh 3.7V batteries, I also purchased a Nitecore D4 Intellicharger Universal Battery Charger, I used that batteries once on my diving torch until the runned out of power.
> 
> Now I try to charge them but only one did get recognized and charged the other is completely dead and no volts register on the multimeter.



Consider it a lesson, and don't buy them again. There are no 5800 mAh 26650s. That capacity number is a LIE, pure and simple. Many ****Fire cells are poor quality, might even be used/recycled cells. STAY AWAY!


----------



## ven

As above,i cant add and agree 100% ,the highest is 3600mah right now,most easiest to find are 3400mah,stick with known brands....

If cost is an issue 3100mah or even 2600mah if run times are not over important.....

Panasonic A or B cells,Sanyo,LG,Samsung.........brand wise i could go on,as important,buy from a reputable shop,ideally local or same country to avoid potential issues and waiting times..............


----------



## thedoc007

ven said:


> As above,i cant add and agree 100% ,the highest is 3600mah right now,most easiest to find are 3400mah,stick with known brands....



We were discussing 26650...the highest capacity is 5200 mAh. 18650s top out at 3600 mAh.


----------



## ven

thedoc007 said:


> We were discussing 26650...the highest capacity is 5200 mAh. 18650s top out at 3600 mAh.



My apologies i really need to read and make sure i understand!!! too much happening!!

I can add that kinoko and xtar make great 26650 cells,i have also had good results from mnke too


----------



## pbolomey

Thanks guys, will keep away from them. Now I'm in AU can anyone recommend a good supplier. 


Sent from my iPad using Candlepowerforums


----------



## BlueFox

Hi,

I decided to buy a torch with a 18650 rechargeable battery: 
http://www.amazon.co.uk/dp/B00HN1NU2Y/

And then read on this forum and elsewhere some of the issues with 18650 batteries.

If I dispose of the battery that comes with this torch (as probably unprotected) and also the charger (as cheap chinese chargers can be dodgy) and got a decent branded 1860 battery from a reputable supplier and used my regular mobile phone charger (as the torch has usb lead), would that cover all the known bases?

PS Regular mobile phone chargers don't indicate when the battery is fully charged. Is that an issue for a 18650 battery? AFAIK mobile phones have lithium batteries so if phone chargers are safe with phones, presumably they are safe with a 18650 in a torch??


----------



## SilverFox

Hello BlueFox,

Welcome to CPF.

Phones have a circuit that manages the charger. The charger just supplies power. 

It is not recommended to use a phone charger (unless it has charge management built into it) for charging individual cells.

Tom


----------



## jimbo231

*Default Re: Using Li-ion cells in LED flashlights safely*

*18650 Headlamp... Will I blow my head off?*

I have a few 18650/lights with aw cells and I know the dangers of li-ion cells. I was thinking of buying an 18650 headlamp and wondered If it would be a smart thing strapping a 18650 to my head? I have good protected cells but can they just explode while using the light?


----------



## SilverFox

*Re: Default Re: Using Li-ion cells in LED flashlights safely*

Hello Jimbo231,

Since most headlamps use a single cell and since most of the issues with 18650's occur during charging, your head should be OK...

Tom


----------



## fhtrucker

it all sounds a bit of a worry and effort to keep safe with the li- ion cells. is it worth it over any other battery?maybe i should stick with my old everready torch.


----------



## rwfishman

I tried posting this before but something funky happened, so hopefully this is not a dupe.

I would like to know if the "High performance 3400mAh Orbtronic (Panasonic inside) PROTECTED 18650 Li-ion 3.7V rechargeable battery cell."is a good choice for a Zebralight SC62w, Nitecore SRT7, and a Nitecore P12? If not, what would you recommend. I guess length is the issue (it needs to be 69mm).

Also, I've seen some pretty awakening warnings on battery sites so I know I need to do some homework. I'm trying to work my way around this site, but until I learn my own way, can anyone send me a couple of links on the basics of safe handling and charging of Lithium Ion rechargeable batteries? It would be greatly appreciated.
Thanks


----------



## precisionworks

rwfishman said:


> ... I would like to know if the "High performance 3400mAh Orbtronic (Panasonic inside) PROTECTED 18650 Li-ion 3.7V rechargeable battery cell."is a good choice for a Zebralight SC62w, Nitecore SRT7, and a Nitecore P12? ... length is the issue (it needs to be 69mm).


The 3400 Panasonic's are all I run in every light. P2X, P3X, Powertac E5, Nitecore EC20, etc. They run both fat (18.9mm) & long (69-70mm for button tops). Buy the genuine Japanese Panasonic's, charge only in a high quality charger & don't worry for a minute.







The Orbtronic Panasonics are fine batteries but a little pricey. The ones shown above are from R-L Sales on eBay, $8.95 delivered per battery. Look at item #390549663507. Shipping is always fast & free.


----------



## Jim Fairbairn

I've read that you can get up to 500 full charges from a Li-ion battery. What is the maximum shelf life of a Li-ion battery and what is the best way to store li-ion batteries to maximize shelf life?


----------



## thedoc007

Jim Fairbairn said:


> I've read that you can get up to 500 full charges from a Li-ion battery. What is the maximum shelf life of a Li-ion battery and what is the best way to store li-ion batteries to maximize shelf life?



There is no date at which a cell will suddenly stop working. It is a matter of degree...and depends greatly on temperature and state of charge. They should be stored at about 40% charge, or 3.55-3.6 volts if not used for an extended period (for standard nominal 3.7V cells). They should be stored in a cool, dry environment. If you do those things, they have a shelf life of several years.

With that in mind, though, it seems foolish to me to use lithium ion cells for applications where you won't be using them for months at a time. Better to use lithium primaries, which have a longer shelf life, and a lower initial cost. Rechargeable cells are meant to be used, not stored, and their value is wasted if you just buy and them store them.


----------



## magellan

Although it depends on the type of lithium ion chemistry, in general the two worst things for lithium ions are over-discharging and charging and then using them immediately (especially running them hard) without giving the cells an hour or so to "rest." 

This forum and BatteryUniversity.com has lots of great info on using them safely.

Also you should invest in a quality charger from Xtar or Nitecore. 

If you observe a few precautions you should be okay.








fhtrucker said:


> it all sounds a bit of a worry and effort to keep safe with the li- ion cells. is it worth it over any other battery?maybe i should stick with my old everready torch.


----------



## magellan

Besides this site try BatteryUniversity.com. I can also recommend the book, Batteries in a Portable World, by Isidor Buchmann, available on Amazon. I got the Kindle version. It gets very good reviews on Amazon.



rwfishman said:


> I tried posting this before but something funky happened, so hopefully this is not a dupe.
> 
> I would like to know if the "High performance 3400mAh Orbtronic (Panasonic inside) PROTECTED 18650 Li-ion 3.7V rechargeable battery cell."is a good choice for a Zebralight SC62w, Nitecore SRT7, and a Nitecore P12? If not, what would you recommend. I guess length is the issue (it needs to be 69mm).
> 
> Also, I've seen some pretty awakening warnings on battery sites so I know I need to do some homework. I'm trying to work my way around this site, but until I learn my own way, can anyone send me a couple of links on the basics of safe handling and charging of Lithium Ion rechargeable batteries? It would be greatly appreciated.
> Thanks


----------



## marc.collin

is there any plus to use 18650 imr battery (over a icr) for a led (xhp70)?


----------



## thedoc007

marc.collin said:


> is there any plus to use 18650 imr battery (over a icr) for a led (xhp70)?



The XHP-70 requires six volts minimum, so one 18650 usually won't power it at all. Whether or not IMR cells make sense depends on how many cells are you using. If only two, then yes, IMR will likely do better. The XHP-70 draws a LOT of power. If you are using four cells, chances are standard ICR cells can handle the load fine (depending on how hard you are driving it).


----------



## marc.collin

i'm thinking to use around 10

don't know if using AA in term of power/size will be better


----------



## thedoc007

marc.collin said:


> i'm thinking to use around 10
> 
> don't know if using AA in term of power/size will be better



Then no, ICR cells will do fine.

One 18650 is roughly equivalent to four AA cells. So 18650s are definitely the way to go if you want power for size.


----------



## marc.collin

any good seller to get excellent 18650 battery at the lowest price
want to buy 50 to begin.


----------



## thedoc007

marc.collin said:


> any good seller to get excellent 18650 battery at the lowest price
> want to buy 50 to begin.



Wow...that is one heck of a start. 

Where are you located?


----------



## marc.collin

Quebec, Canada


----------



## thedoc007

Probably the cheapest cells would be direct shipped from overseas, then. Fasttech is one place I like...but you will definitely have a long wait, and there is always a chance packages will be held up or even refused by Customs. Mountain Electronics (USA) would undoubtedly be faster, but I don't know how much shipping would be (though I'd guess for an order that large it might be quite reasonable as a percentage of the total cost).

If you want a local company, I can't help you...don't know any good Canadian suppliers. Did you try searching CPF already? This is not the first time a similar question has been asked...


----------



## NoNotAgain

One of the issues you might have is that the shipping regulations on lithium cells changed early this year. From what I read, they can ship 8 18650 batteries in one container, but I've found no limits on what is referred to as over pack. 

Until the shippers figure out what's good and what's bad, you are going to have issues with shipping batteries.

This is a snipit from the UPS shipping regulations:
http://www.google.com/url?sa=t&rct=...6CE-Uk9Atf5y1klvLNdErgQ&bvm=bv.86956481,d.eXY

Shipping lithium batteries by ground service
Additional weight and labeling requirements now apply to ground
shipments of lithium batteries in the U.S. The requirements differ
depending upon what type of lithium battery you are shipping
(lithium ion or lithium metal) and whether you are shipping batteries
packed without equipment, batteries packed with equipment,
or batteries contained in equipment. Please see Figure 8 (Page 9)
and Figure 10 (Page 11) for additional information.
These requirements also apply to cross-border ground shipments
from the U.S. to Canada and Mexico.


----------



## 1DaveN

thedoc007 said:


> With that in mind, though, it seems foolish to me to use lithium ion cells for applications where you won't be using them for months at a time. Better to use lithium primaries, which have a longer shelf life, and a lower initial cost. Rechargeable cells are meant to be used, not stored, and their value is wasted if you just buy and them store them.



Thanks for that. It's something I've been thinking about, and the way you worded it made a light bulb go off over my head.


----------



## TSellers

marc.collin said:


> Quebec, Canada



It's a good idea to be mindful that 50 18650 cells arriving in Canada from a foreign destination will place that shipment into the realm of a commercial shipment. That means it needs to be accompanied by a commercial invoice which is then used in the preparation of a 'B3' Canada Customs form. It is mandatory for this form to be submitted to CBS (Canada Border Services) for clearance of the shipment upon payment of duties and taxes. Normally, getting a B3 filled out and submitted properly requires the services of a customs broker service, and many of the commercial carriers have such a fee based service. The way around that is to get 5 or perhaps even 10 cells at a time. While postal shipments from China normally arrive without being held by Canada Post for collection of taxes, for some reason most shipments that originate in the USA will be held for payment of taxes and duty. No B3 is required, and the customer pays the post office the assessed duties and taxes plus a $5.00 collection fee when picking the package up.


----------



## marc.collin

TSellers said:


> It's a good idea to be mindful that 50 18650 cells arriving in Canada from a foreign destination will place that shipment into the realm of a commercial shipment. That means it needs to be accompanied by a commercial invoice which is then used in the preparation of a 'B3' Canada Customs form. It is mandatory for this form to be submitted to CBS (Canada Border Services) for clearance of the shipment upon payment of duties and taxes. Normally, getting a B3 filled out and submitted properly requires the services of a customs broker service, and many of the commercial carriers have such a fee based service. The way around that is to get 5 or perhaps even 10 cells at a time. While postal shipments from China normally arrive without being held by Canada Post for collection of taxes, for some reason most shipments that originate in the USA will be held for payment of taxes and duty. No B3 is required, and the customer pays the post office the assessed duties and taxes plus a $5.00 collection fee when picking the package up.




if i think only in pack of 10, shipping charge will be high

don't know if i will save a lot if i get 50


----------



## TSellers

marc.collin said:


> if i think only in pack of 10, shipping charge will be high



Yes, that is the problem for US based suppliers, USPS Shipping charges are high for them, which places them at a disadvantage compared to Chinese sellers for sending products to foreign clients.


----------



## marc.collin

TSellers said:


> Yes, that is the problem for US based suppliers, USPS Shipping charges are high for them, which places them at a disadvantage compared to Chinese sellers for sending products to foreign clients.



a good 18650 at 3400mAh it's easy 10$ without tax and shipping in canada


----------



## NoNotAgain

Do you have any vape shops in Canada? If so you should take a look at them for a source for batteries.

Per the changes to USPS shipping regulations, you can't ship more than 8 cells in a package. 

Do you have any plans to visit the US in your future? If so, just wait until you get here and make your purchase here. Bring your lights empty so that you can fill them up with batteries for the return trip.

The supplier I recently used has a vape shop. I purchased another 12 batteries from him after the new rules took effect. I called him up to let his know that the new shipping rules no longer allowed for large shipments (over 8 cells) in USPS mail. He thanked me, and raised the price on new purchases to cover the increased postage costs.

It's going to get rough getting batteries at the old prices with the shipping changes.


----------



## marc.collin

so the only way to get big quantity of 18650 will be by boat.


----------



## fadetoblack73

I own 2 PowerTac Warrior "Reloaded" model lights. They work absolutely wonderfully. The reason that I chose the lights is that their storage cradle also re-charges the lights. This is the difference between the "Reloaded" model and the standard Warrior model. I love the fact that as long as you return the light to its proper place after using, you know it is going to be charged for the next use. But after reading this thread, I am now concerned. The charger is, supposedly, protected against over-current and over-heating. It is also supposed to automatically NOT try to charge primary CR123 batteries if they are accidentally left in the light. But, this thread has me worried that all of these built-in protections are not good enough. Surely a company would not design a product that would be potentially dangerous even when used as designed. Imagine the lawsuits if this thing weren't tested.

Can someone offer an opinion one way or another?


----------



## loquutis79

Marc.collen, have you tried Keenbeam? He is located in the Ottawa Valley and sells Eagletac brand 18650's. Very good batteries. Also there is Mackoutdoors in B.C. I believe. He has AW's as well as Eagletac I think. Both are good guys to deal with. And then a few blocks from me here in the Toronto area is a guy who sells Fenix. He sells Fenix brand 18650's only. I like the lights but I prefer the Eagletac cells better. But he might be the better bet for a quantity price break. Not so sure about the first two places.
Anyway, Google the names, you will find them. For the Fenix guy google "Fenix Tactical"


----------



## hrbngr

Checking in here, any recommended current Amazon/ebay sellers of Button-Top Panasonic 18650B 3400s currently? Also, per this thread and others, the Pila IBC batter charger was reputed to be a great charger, but I can't seem to find it for sale currently, so was wondering what is the go-to safest charger right now? Xtar?


----------



## thedoc007

hrbngr said:


> Checking in here, any recommended current Amazon/ebay sellers of Button-Top Panasonic 18650B 3400s currently? Also, per this thread and others, the Pila IBC batter charger was reputed to be a great charger, but I can't seem to find it for sale currently, so was wondering what is the go-to safest charger right now? Xtar?



I wouldn't personally recommend you buy 18650s from Amazon. Not because they are more likely to be fake, but because they are simply more expensive. Even when you take shipping into account, you will pay more on Amazon for good cells.

I'd recommend Mountain Electronics or Illumination Supply in the USA. They have tons of options for cells, they don't sell junk, they have a presence on CPF, they have good customer service and fast shipping, and they are cheaper. What's not to like?

Pretty much any quality charger is safe enough. They aren't that complex, and if you charge when you are around, nothing to worry about even in the worst case. The Xtar VP2 and Nitecore D4 are my current favorites. VP2 is better if you have only a few cells, and only li-ion. The D4 does lithium-ion and NIMH, and has a couple extra bays. Both are simple to use, have good charge algorithms, digital readouts so you can keep track of progress, and multiple charging options.


----------



## HighZenBurg

Wow! Thank you!!
I just read this thread from start to finish and it answered most of my questions regarding Liion battery safety. It's a 6 year evolution to this point, and interesting to see how the battery options and their protection has evolved. I like to think that today's Liion batteries are very much safer than when this thread began.

I'm very new to all this stuff, and a first time poster on CPF. I'm about to impart on a long camping/road trip and needed a couple flashlights, so I wanted to find some great options and not break the bank. After some research I went on a pretty serious flashlight bender, I think I've made some good decisions. Please let me know what you think. 

This is what I've bought in the last few days:

Nitecore mh12 - with 18650 3400 mAh (like P12 but has usb charger built in)
xtar vp2 charger
Orbitron 18650 - 3400 mAh protected and designed for flashlights. (4 pack)
Solarforce - L series torches in various formats with different drop-ins (3x)

I hope these batteries work with the Solarforce torches. I need to do more research to make sure these have protected circuits built in to protect from over discharging.

Should I only use the Nitecore battery with the nitecore mh12, or is it just fine to use Orbitron? I would imagine it's best to use all nitecore circuitry, but again I'm a Noob!

Thank you everyone. My OCD had new fuel. 👻


----------



## thburns

thedoc007 said:


> I wouldn't personally recommend you buy 18650s from Amazon. Not because they are more likely to be fake, but because they are simply more expensive. Even when you take shipping into account, you will pay more on Amazon for good cells.
> 
> I'd recommend Mountain Electronics or Illumination Supply in the USA. They have tons of options for cells, they don't sell junk, they have a presence on CPF, they have good customer service and fast shipping, and they are cheaper. What's not to like?
> 
> Pretty much any quality charger is safe enough. They aren't that complex, and if you charge when you are around, nothing to worry about even in the worst case. The Xtar VP2 and Nitecore D4 are my current favorites. VP2 is better if you have only a few cells, and only li-ion. The D4 does lithium-ion and NIMH, and has a couple extra bays. Both are simple to use, have good charge algorithms, digital readouts so you can keep track of progress, and multiple charging options.



I really wish I would have read the rest of this thread before I bought the batteries for the ZebraLight SC62W and the Nitecore MH-20 that I have coming this week! The MH-20 I bought in a bundle that comes with an NL-189, and I figured I'd want a spare for each light so I got a charger bundle with a D2 and two NL189s, and another charger bundle with a UM10 and a single NL189. Then I saw somewhere that the NL-189s might be too large for the SC62W so I bought two ZL634s from ZebraLight 

Sounds like I should have just bought the chargers by themselves and four Panasonic 18650Bs :mecry:


----------



## recDNA

I have about 4 AW Imr batteries and 6 AW protected ICR batteries. They are all different sizes and all purchased in 2010. (I actually have 4 more purchased this year but no questions about them.)

All of these 5 year old batteries charge on my Pila charger or Xtar charger without issue. All charge to act least 4.11 volts. Most to 4.15 volts. My Pila never charges any battery above 4.18 volts.

Their age concerns me even though they work fine. Are they still safe to use or should I recycle them? Thanks!


----------



## SilverFox

Hello recDNA,

If they were mine I would continue to use them.

Tom


----------



## lunas

Just did a check on my stored cells I have 3 trustfire 14500 and 3 ultrafire 2x 14500 1x 18650cells still need to check the 18650 size ultrafire but one of the 2 14500 ultrafires has self discharged to 1.75v well time to chuck the trustfires all seem to hold the charge better but I have already thrown 1 away as it dropped suddenly to 0v by itself.

In 30 mins off the charger the 14500 ultra fire was at 4.12v I a bit ill check again if it under 4v ill just chuck it. Even though I should chuck all 6 of them.


----------



## xzel87

Have a very quick question on batteries...

So I recently got myself the BLF Special Edition A6, which is able to draw up to 5A and more...Needless to say, it gets hot really fast. The question is, as the body of the light heats up, so does the cell inside the battery tube. When I take out the battery right after it is rather warm. Is this of any danger whatsoever?

The cell I'm using in this case is a Samsung 25r.


----------



## lunas

Yes you need to make sure to use high quality cells that can handle that draw they are getting hot due to the draw too hot they out gas and vent.


----------



## thedoc007

xzel87 said:


> So I recently got myself the BLF Special Edition A6, which is able to draw up to 5A and more...Needless to say, it gets hot really fast. The question is, as the body of the light heats up, so does the cell inside the battery tube. When I take out the battery right after it is rather warm. Is this of any danger whatsoever?
> 
> The cell I'm using in this case is a Samsung 25r.



Cells getting too hot can be an issue in extreme circumstances. But your setup is fine...that is a good cell, and the right fit for that light. IMR/INR cells are definitely safer for high-draw and/or high heat applications. Absolutely no problem for you.


----------



## xzel87

lunas said:


> Yes you need to make sure to use high quality cells that can handle that draw they are getting hot due to the draw too hot they out gas and vent.





thedoc007 said:


> Cells getting too hot can be an issue in extreme circumstances. But your setup is fine...that is a good cell, and the right fit for that light. IMR/INR cells are definitely safer for high-draw and/or high heat applications. Absolutely no problem for you.



Thanks for the input people...the battery just gets warm, not to the level of being too hot to hold. The flashlight body however, if left tailstanding for 10 minutes (I use it ceiling bounce on max to illuminate a group photo) it does get unbearably hot to hold initially. I guess that's not such a bad thing as it would mean heat is being dissipated from the head throughout the body?


----------



## Dr. Tweedbucket

Awesome info in this thread! Thanks a million!!!!


----------



## oriels

thank you that very help me.
but i got a question - you said that i need to watch my battery every 15 minutes max and that not overreacting. but what about when people are put theirs phone in charge all night ? and sleep with it next to theirs head?


----------



## thedoc007

oriels said:


> thank you that very help me.
> but i got a question - you said that i need to watch my battery every 15 minutes max and that not overreacting. but what about when people are put theirs phone in charge all night ? and sleep with it next to theirs head?



One difference is that a phone is a fully integrated system. with advanced charging and (hopefully) fail-safes in case something goes wrong. Every component, battery, electronics, cables, charger, etc., are each individually and collectively tested by the manufacturer in the development phase to make sure everything is compatible. Even then sometimes unforeseen problems occur, but hopefully not very often. YOU are the systems integrator for your lights...you are solely responsible for picking out a good charger, good cells, and using everything properly.

That said, I think there is a LOT of paranoia out there regarding charging. Watching it continuously is unnecessary, and checking it every fifteen minutes doesn't in ANY way guarantee safety either. I don't charge if I am not going to be around...for the same reason I don't leave the stove on when I am out. Anything can happen. But if you really are so worried about it that you cannot leave a cell charging for more than fifteen minutes without attention, I think this is very much the wrong hobby for you.


----------



## lunas

xzel87 said:


> Thanks for the input people...the battery just gets warm, not to the level of being too hot to hold. The flashlight body however, if left tailstanding for 10 minutes (I use it ceiling bounce on max to illuminate a group photo) it does get unbearably hot to hold initially. I guess that's not such a bad thing as it would mean heat is being dissipated from the head throughout the body?


yeah i have a couple lights like that my new thorfire TG06 on high gets warm in about 2 minutes of use. We call these lights hand warmers...

Most high power led lights will heat up very hot. All my xml and both my xpg2 get hot it is when one of these 300+ lumen lights don't make any noticeable heat you need to worry as it means the led are thermally isolated from the body of the light. The confined heat will eventually burn out the led or if the driver is good it will throttle.

an example of throttling is the fenix e99 ti or the fenix e05 2014 model will only stay in high mode for 3 minutes then kick down to medium.


----------



## JLB

Thanks for the information. I have left my 18650's in my chargers overnight. I have a Pila and thought it was safe to leave them in there. I guess no more.


----------



## recDNA

I feel the need to often touch batteries for signs of heat. I would never leave it alone for 15 minutes. I don't care what the charger or battery is. One of these days I need to buy an infrared thermometer so I can more easily check heat of charging cells.


----------



## lumensearch

Evening guys

I'm looking for some average weights of 18650's, against capacity....any pointers?


----------



## sidecross

I have 40 18650 batteries bought in groups of ten over the last 20 months. Each group is separate by manufacturer and mAh ratings. I have 10 Eagletac 3100mAh, 10 Keeppower 3100mAh, 10 Eagletac 3400mAh, and 10 Keeppower 3400mAh. It is easy to keep these batteries in groups for my lights that use 4 18650's and 2 18650's.


----------



## Flashy808

What voltage should 14500 Li-ion batteries be charged to? From what I can see it is 4.2 volts (as mentioned it multiple places on CPF) but on the actual battery itself it says it is rated for 3.7 volts.

Can someone please help clarify? :thinking::thinking:

Oh and BTW if those 14500 batteries were only supposed to be charged to 3.7v I may have made a little boo boo .

Thanks!


----------



## ven

Hi there , the 3.7v is the nominal voltage, yes charged to 4.2v


----------



## lunas

Flashy808 said:


> What voltage should 14500 Li-ion batteries be charged to? From what I can see it is 4.2 volts (as mentioned it multiple places on CPF) but on the actual battery itself it says it is rated for 3.7 volts.
> 
> Can someone please help clarify? :thinking::thinking:
> 
> Oh and BTW if those 14500 batteries were only supposed to be charged to 3.7v I may have made a little boo boo .
> 
> Thanks!


3.7 is the nominal voltage they will drop to under load 4.2 is the max voltage +-5% they should rest at. 3.0 is the absolute minimum they should be allowed to be discharged to most protection will turn off at 3.3. There are some that go to 2.8 but those make people round here nervous... And of course im talking individual cells not packs.

Also with a good charger the charger will charge them at 350mA or 750mA a few will actually fast charge at over 1A to 3.7v then trickle charge them the final bit to 4.2 before turning off.

In general a battery can be charged at 1c there are a few that do 2c charging but those are typically Lipo the c rating of the battery is used to describe the discharge they can do and the charge rate they can do a 14500 is typically between 600mAh and 1200mAh the 1200mAh are usually fakes and 700 or 750 is more likely a cell that is 750mAh and can charge at 1c means it can charge at 750mA this should charge one of these cells very quickly. Pushing tolerance is what breeds disaster and pushing 750mA in to a battery that maxes out at 750 is a good way to vent them even if they claim they can take it.


----------



## HKJ

lunas said:


> 3.7 is the nominal voltage they will drop to under load 4.2 is the max voltage +-5% they should* rest *at.



No, they should be charged at, rest will usual be lower.




lunas said:


> 3.0 is the absolute minimum they should be allowed to be discharged to most protection will turn off at 3.3. There are some that go to 2.8



Protection usual trips between 2.0 volt and 2.5 volt (I did some test here: http://lygte-info.dk/info/DischargeProtectionTest UK.html ).
Minimum voltage during discharge is usual rated at 2.5, 2.75 or 3.0 volt, depending on the cell, resting voltage will usual be well above 3 volt.


----------



## Flashy808

Oh I think I understand now. So you charge all cells to 4.2 volts but after letting it rest for about [how long??] should bring it back down to its nominal voltage?

If this correct then should I let the battery rest until it reaches 3.7v before resuming use or just jump straight in?

& am I correct in assuming Nominal Voltage= Voltage at when rested and what it is normally suppose to produce?

Thanks


----------



## thedoc007

Flashy808 said:


> Oh I think I understand now. So you charge all cells to 4.2 volts but after letting it rest for about [how long??] should bring it back down to its nominal voltage?
> 
> If this correct then should I let the battery rest until it reaches 3.7v before resuming use or just jump straight in?
> 
> & am I correct in assuming Nominal Voltage= Voltage at when rested and what it is normally suppose to produce?
> 
> Thanks I would have never known!




Heh, no, you don't have it yet. 

Nominal voltage has little or nothing to do with resting, or charging, or loading a cell. A typical li-ion works from 4.2 down to 2.5 volts or so - the nominal voltage is just an arbitrary value somewhere in that range. That's why you see some manufacturers list 3.6, and some list 3.7 volts as the "nominal" value. Neither is empirically more accurate...the nominal voltage is there only as a general guideline. I.e., you know not to put a 3.7 volt cell in a light that has a range of 0.9 to 2 volts, for example. But a (nominal) 3.7 volt cell can be 2.9 volts under load, or 4.1 volts at rest, or 3.1 volts at rest, or 3.8 volts under load. Note that this "nominal" voltage applies to NiMH, lithium, alkalines, and every other kind of cell, not just li-ion. None of them maintain exactly the same voltage throughout a full cycle. 

3.7 volt li-ions typically will safely charge to 4.2 volts, approximately. As soon as it is removed from the charger, the voltage will sag a very small amount. Perhaps 4.2 volts to 4.17 volts, for example. This is perfectly normal, and does not mean the cell isn't fully charged. In fact, if you see 4.2 volts at rest, that means the cell was at least slightly overcharged. Also remember that cell ratings are usually +- .05 volts, though, so a reading of 4.21 or 4.18 volts is fine too. No need to be worried about it unless the cell is out of that recommended range. 

The voltage under load is dependent on how much current you are pulling from the cell, and what chemistry it uses. IMR, for example, can typically deliver higher currents, and sag less under load. The trade off is lower capacity. A cell charged to 4.2 volts might sag to 3.9 volts right away under a three amp load, for example, and then gradually decline as the cell is depleted. 

You can use a cell immediately after charging. There is no need to wait for the voltage to settle.

You have heard from HKJ here, but this is one of his write-ups I have found particularly useful. Thanks HKJ!


----------



## Flashy808

thedoc007 said:


> Heh, no, you don't have it yet.
> 
> Nominal voltage has little or nothing to do with resting, or charging, or loading a cell. A typical li-ion works from 4.2 down to 2.5 volts or so - the nominal voltage is just an arbitrary value somewhere in that range. That's why you see some manufacturers list 3.6, and some list 3.7 volts as the "nominal" value. Neither is empirically more accurate...the nominal voltage is there only as a general guideline. I.e., you know not to put a 3.7 volt cell in a light that has a range of 0.9 to 2 volts, for example. But a (nominal) 3.7 volt cell can be 2.9 volts under load, or 4.1 volts at rest, or 3.1 volts at rest, or 3.8 volts under load. Note that this "nominal" voltage applies to NiMH, lithium, alkalines, and every other kind of cell, not just li-ion. None of them maintain exactly the same voltage throughout a full cycle.
> 
> 3.7 volt li-ions typically will safely charge to 4.2 volts, approximately. As soon as it is removed from the charger, the voltage will sag a very small amount. Perhaps 4.2 volts to 4.17 volts, for example. This is perfectly normal, and does not mean the cell isn't fully charged. In fact, if you see 4.2 volts at rest, that means the cell was at least slightly overcharged. Also remember that cell ratings are usually +- .05 volts, though, so a reading of 4.21 or 4.18 volts is fine too. No need to be worried about it unless the cell is out of that recommended range.
> 
> The voltage under load is dependent on how much current you are pulling from the cell, and what chemistry it uses. IMR, for example, can typically deliver higher currents, and sag less under load. The trade off is lower capacity. A cell charged to 4.2 volts might sag to 3.9 volts right away under a three amp load, for example, and then gradually decline as the cell is depleted.
> 
> You can use a cell immediately after charging. There is no need to wait for the voltage to settle.
> 
> You have heard from HKJ here, but this is one of his write-ups I have found particularly useful. Thanks HKJ!



Hmm I think I am starting to get it now. 
It's mainly the under load and nominal relationship that I didn't understand. 

Thanks doc for helping! & of course everyone else .


----------



## Phlogiston

As thedoc007 says, the most common types of Li-Ion cell can have an observed voltage of anything from 2.5V to 4.2V, depending on the cell's state of charge and how heavy the load is. Lower levels of charge and / or heavier loads reduce the observed voltage of the cell. 

Note that most people prefer to keep their cells over 3V, to minimise the risk of accidental over-discharge and damage to the cell, especially given that not all cells are rated to go as low as 2.5V. A fair few people opt for higher voltages still. 

As far as the nominal voltage goes, it might help if you think of it as an "average" voltage, seen during a manufacturer's capacity tests as the cell goes from fully charged to fully depleted.


----------



## Flashy808

Phlogiston said:


> As thedoc007 says, the most common types of Li-Ion cell can have an observed voltage of anything from 2.5V to 4.2V, depending on the cell's state of charge and how heavy the load is. Lower levels of charge and / or heavier loads reduce the observed voltage of the cell.
> 
> Note that most people prefer to keep their cells over 3V, to minimise the risk of accidental over-discharge and damage to the cell, especially given that not all cells are rated to go as low as 2.5V. A fair few people opt for higher voltages still.
> 
> As far as the nominal voltage goes, it might help if you think of it as an "average" voltage, seen during a manufacturer's capacity tests as the cell goes from fully charged to fully depleted.



Ah that sound just about reasonable. Thanks.

This may be a little off topic but:
Why is mAh the rating for battery capacity? Should it be a rating for current/flow as it is how many milliamperes an hour?
I don't understand I though milliamperes measures the amount of power.

Thanks for you comments.


----------



## Phlogiston

The reason battery ratings are in mAh is so that you can see how much current you can draw for how long. In theory, it tells you how much current you can draw if you want the battery to last one hour - current in "mA" for a period of one "h". Twice the current for half an hour, half the current for two hours, and so on. 

You could just as easily rate the cell in mWh - power in "mW" for a period of one "h" - but historically, most electrical systems have been designed to work at one particular voltage and that's that. In that context, once you've put the right cell in, voltage becomes almost irrelevant, because you can always figure out runtime using just the current draw and the mAh rating. There's no need to go as far as thinking about power. It's also easier and cheaper to build a current meter than a power meter. 

Of course, nowadays we have devices like flashlights which accept a wide range of input voltages and draw however much current it takes to maintain the correct power level. In that context, it can be easier to use mWh instead of mAh, because that automatically takes account of the voltage differences between 1.2V NiMH, 1.5V primary lithium and 3.7V Li-Ion cells, for example. 

Most people don't need to bother with that, though. Nine times out of ten, all you need to do is pick the right cell type - 3.7V Li-Ion, say - and compare mAh ratings to see which cell will give you the most runtime. 

On a related note, manufacturers have a nasty tendency to stretch their mAh ratings by testing at lower currents for longer periods, taking advantage of the fact that virtually all batteries are most efficient at low discharge currents relative to their capacity. It's quite unusual to find a cell that will actually supply its mAh rating over an hour. 

For example, a 3000mAh 18650 cell may well be rated at a discharge current of 0.2C - 20% of its mAh-rated current. In other words, it would be discharging at 600mA for 5 hours to achieve its mAh rating. You'd be lucky to actually get 3000mA out of it for an hour, despite the fact that drawing 3000mA is perfectly normal and many devices do exactly that. 

This means that you can normally use a cell's mAh rating to get a reasonable idea of the runtime your device might achieve, but it won't be exact, and you're well advised to assume that you'll actually get a bit less in real life. 

The only way to be certain of your device's runtime on a given cell is to put the fully-charged cell in, run the device normally and see how long it takes for the cell to run out of energy.


----------



## Flashy808

Phlogiston said:


> The reason battery ratings are in mAh is so that you can see how much current you can draw for how long. In theory, it tells you how much current you can draw if you want the battery to last one hour - current in "mA" for a period of one "h". Twice the current for half an hour, half the current for two hours, and so on.
> 
> You could just as easily rate the cell in mWh - power in "mW" for a period of one "h" - but historically, most electrical systems have been designed to work at one particular voltage and that's that. In that context, once you've put the right cell in, voltage becomes almost irrelevant, because you can always figure out runtime using just the current draw and the mAh rating. There's no need to go as far as thinking about power. It's also easier and cheaper to build a current meter than a power meter.
> 
> Of course, nowadays we have devices like flashlights which accept a wide range of input voltages and draw however much current it takes to maintain the correct power level. In that context, it can be easier to use mWh instead of mAh, because that automatically takes account of the voltage differences between 1.2V NiMH, 1.5V primary lithium and 3.7V Li-Ion cells, for example.
> 
> Most people don't need to bother with that, though. Nine times out of ten, all you need to do is pick the right cell type - 3.7V Li-Ion, say - and compare mAh ratings to see which cell will give you the most runtime.
> 
> On a related note, manufacturers have a nasty tendency to stretch their mAh ratings by testing at lower currents for longer periods, taking advantage of the fact that virtually all batteries are most efficient at low discharge currents relative to their capacity. It's quite unusual to find a cell that will actually supply its mAh rating over an hour.
> 
> For example, a 3000mAh 18650 cell may well be rated at a discharge current of 0.2C - 20% of its mAh-rated current. In other words, it would be discharging at 600mA for 5 hours to achieve its mAh rating. You'd be lucky to actually get 3000mA out of it for an hour, despite the fact that drawing 3000mA is perfectly normal and many devices do exactly that.
> 
> This means that you can normally use a cell's mAh rating to get a reasonable idea of the runtime your device might achieve, but it won't be exact, and you're well advised to assume that you'll actually get a bit less in real life.
> 
> The only way to be certain of your device's runtime on a given cell is to put the fully-charged cell in, run the device normally and see how long it takes for the cell to run out of energy.



:duh2:  Wow full marks for effort! :thumbsup:

I think I understand now. They use mAh to show how much can be drawn for how long so they use that to show how much is in the battery. 

And is it because it is more convenient and common for manufacturers to use mAh instead of just mA right?

Also just to be sure milliamperes and amps are still the actual measure for how much power right?
Then how would you work out say how many mA an 3000mAh battery has? 
-So basically how to convert from current to amount. BUT in the process of typing this I realise that it's not possible to know exactly how much mA a battery contains without getting your battery and draining it out over a period of time right at a rate right?? :shrug: 

So I guess I'll just go by what I (and many) always go by: higher mAh=higher capacity, check manufacturers' voltage needs, don't worry about current too much!

& one last thing: just out of curiosity how might one go about converting mAh to mWh (I totally agree that it should be more common to have a mWh rating to take into account the voltages)?:twothumbs

Few that's a lot of questions .
Btw: Feel free to correct me where I'm wrong.
Thanks for Responding Phlogiston :thumbsup:


----------



## Phlogiston

Flashy808 said:


> Also just to be sure milliamperes and amps are still the actual measure for how much power right?



Milliamperes and amps are current. Power would be milliwatts and watts, which you get when you multiply voltage by current. 



Flashy808 said:


> Then how would you work out say how many mA an 3000mAh battery has?



This question doesn't really have an answer. You can draw as many or as few mA from a cell as you like, as long as you stay below the cell's maximum current ratings. However, you can only have as many mAh as the cell can contain, and then you either have to recharge it or put in a new one. The mA you draw determine how quickly your mAh will be exhausted. 



Flashy808 said:


> & one last thing: just out of curiosity how might one go about converting mAh to mWh (I totally agree that it should be more common to have a mWh rating to take into account the voltages)?



To get mWh, multiply mAh by the nominal voltage. 

For example, a 3000mAh Li-Ion cell with a 3.7V nominal voltage contains 11100mWh. 



Flashy808 said:


> Thanks for Responding Phlogiston :thumbsup:



You're welcome


----------



## Flashy808

Phlogiston said:


> Milliamperes and amps are current. Power would be milliwatts and watts, which you get when you multiply voltage by current.
> 
> 
> 
> This question doesn't really have an answer. You can draw as many or as few mA from a cell as you like, as long as you stay below the cell's maximum current ratings. However, you can only have as many mAh as the cell can contain, and then you either have to recharge it or put in a new one. The mA you draw determine how quickly your mAh will be exhausted.
> 
> 
> 
> To get mWh, multiply mAh by the nominal voltage.
> 
> For example, a 3000mAh Li-Ion cell with a 3.7V nominal voltage contains 11100mWh.
> 
> 
> 
> You're welcome



Very interesting information! Thank you helped a lot.


----------



## ganz-lite

I'm finishing re-saving up to get a 2 18650-celled flashlight from JayRob (Thank you 2 months of undiagnosed pneumonia that culminated in a 105 fever and pneumonia in both lungs). The cells will be protected cells. If I'm not using the flashlight for extended periods, how do I store them to ensure that they stay happy. I'm assuming in a drawer of some sort (not in the flashlight nor the charger). I want happy cells.


----------



## xzel87

ganz-lite said:


> I'm finishing re-saving up to get a 2 18650-celled flashlight from JayRob (Thank you 2 months of undiagnosed pneumonia that culminated in a 105 fever and pneumonia in both lungs). The cells will be protected cells. If I'm not using the flashlight for extended periods, how do I store them to ensure that they stay happy. I'm assuming in a drawer of some sort (not in the flashlight nor the charger). I want happy cells.



Depends whether you are storing the light without the intention to use it during the storage period or storing as an emergency light. If you don't intend to use it, discharge the batteries till 3.7V then store in a cool dry place. Some say place it in an airtight ziploc bag and put in the fridge (some say freezer) but personally I wouldn't do this since you need to let the batteries come back to room temp before charging it.


----------



## ganz-lite

xzel87 said:


> Depends whether you are storing the light without the intention to use it during the storage period or storing as an emergency light. If you don't intend to use it, discharge the batteries till 3.7V then store in a cool dry place. Some say place it in an airtight ziploc bag and put in the fridge (some say freezer) but personally I wouldn't do this since you need to let the batteries come back to room temp before charging it.



It'll be an emergency light.


----------



## xzel87

ganz-lite said:


> It'll be an emergency light.



Then I strongly suggest you go with Lithium Primary batteries i.e. CR123 or Energizer L91s (AA). Put it in and forget about it. Li-Ion Rechargeables can keep their charge for quite a bit, but they will still self discharge, especially more so in extreme weather conditions (hot i.e. car glove box, car parked under baking sun).

EDIT: Forgot that you were referring to your 2x18650 light. Will that be the emergency light you were referring to?

Ideally, for cell longevity, Li-Ion Rechargeable cells are best stored at around 3.7V, however, this is not feasible since you are using it as an emergency light. My advice?, just keep it fully charged inside your light. If the light is kept in a nice cool place (drawer in the house) it should be fine. Capacity loss due to storing batteries fully charged, for us laymen, should not be noticeable at all. Test the light every so often and complete discharge and recharge every 3 months should suffice.


----------



## ganz-lite

xzel87 said:


> Then I strongly suggest you go with Lithium Primary batteries i.e. CR123 or Energizer L91s (AA). Put it in and forget about it. Li-Ion Rechargeables can keep their charge for quite a bit, but they will still self discharge, especially more so in extreme weather conditions (hot i.e. car glove box, car parked under baking sun).
> 
> EDIT: Forgot that you were referring to your 2x18650 light. Will that be the emergency light you were referring to?
> 
> Ideally, for cell longevity, Li-Ion Rechargeable cells are best stored at around 3.7V, however, this is not feasible since you are using it as an emergency light. My advice?, just keep it fully charged inside your light. If the light is kept in a nice cool place (drawer in the house) it should be fine. Capacity loss due to storing batteries fully charged, for us laymen, should not be noticeable at all. Test the light every so often and complete discharge and recharge every 3 months should suffice.



It'll be 2x32650, I'm looking at a jayrob light.

So if i keep it quiet, and if i keep it happy in a cool place (drawer or closet), it'll be happy so long as i discharge it every quarter (ie: walk the dog at night).


----------



## xzel87

ganz-lite said:


> It'll be 2x32650, I'm looking at a jayrob light.
> 
> So if i keep it quiet, and if i keep it happy in a cool place (drawer or closet), it'll be happy so long as i discharge it every quarter (ie: walk the dog at night).



err yeah..you're good...32650 cell should have plenty of charge...

not sure how'd you keep a light quiet though....they tend to be pretty noisy when locked up in a dark drawer all day for 3 months :nana:


----------



## Skaaphaas

I just took my first step into the world of rechargeable batteries, with the receipt of my Nitecore i2 charger and two Nitecore RCR123 cells. 

Thank you for this sticky thread, I have not yet read through it all but I've already learnt a ton.


----------



## Mobileschoney

I agree skaaphass, I just got the same cells (along with a few others) and a Nitecore D4 the other night. The information you learn here is invaluable. 
Thanks all.


----------



## pyro0

This is a very informative post. As a complete noob on batteries, I was going to ask you guys/gals which rechargeable batteries and charger would be a good fit for my situation. I feel kind of hesitant on ordering some now after reading this. Thanks for the warning.


----------



## k3751

I've read the entire thread and think I'm getting a handle on this. Someone please correct me if I'm wrong:

I run an unprotected AW 16340 in my HDS. This is ok because the light itself is protected against over discharging the battery. 

I have an Olight S1 baton, which does not have the same protection in the light as the HDS. I should still be ok running a quality unprotected cell in it because, probable worse case scenario is that I would over discharge the cell and negatively affect its capacity or life span. If I'm semi cautious with charging the cell in accordance with my use, it shouldn't be an issue. 

What about running two unprotected 18500s or 18650s in an MD3 or MD4 body? I know Malkoff suggests protected cells, but I've seen where some people run the AW reds in series. Is this another (probable) worse case scenario of harming the cells, or am I looking at potential damage or injury to myself or the light?

I do not check the voltages of my cells, but charge them after significant use in a Nitecore I2. 

Any guidance is appreciated.


----------



## hsdesai

JBorneu said:


> Ahoy there
> 
> I created this guide because I felt we lacked one single comprehensive guide which tells newbies how to use Li-ion cells in a safe manner in their LED flashlights. Now I know why: At least the "comprehensive" part is impossible.
> 
> 
> *Using Li-ion cells in LED flashlights safely for newbies*
> 
> 
> *5 Chargers....*



Hi
Can you please add some info on the solar powered string lights which have batteries like 3.7v, 14500, 400 mah ICR?
Want to know if it matters which company or quality one buys for a low usage lights like these?
So links to best buys may help if you know
Thank you for the explanation-looks comprehensive and good


----------



## Richierich90000

good article..

the only thing i would add is dont run them flat (or below their lowest voltage)


----------



## Dr. Manhattan

You should mention something about storage. Please clarify if the batteries are ticking bombs which will explode when the discharge under 3V...


----------



## ven

Dr. Manhattan said:


> You should mention something about storage. Please clarify if the batteries are ticking bombs which will explode when the discharge under 3V...



No that wont happen, worse case is when they are charged from a low voltage. Most cells these days have a minimum low of 2.5v(some 2.8v). Its not recommended to go bellow this voltage. If you do, charging asap is key and not to leave for long periods..............this over time causes a build up due to the chemistry inside and can go south when charged. 

Store around 3.6v in a cool dry place if for long periods. If in a flashlight, lock out to eliminate any parasitic drain and check periodically . Even if it means running the light for 5m and topping back off or leaving around 4.1v which can help the life over time(years). 

When a cell is shorted, this causes a risk and with the pressure inside(pipe bomb), so not only are voltage checks important over time, but also checking over the cell, making sure the wrap/s are not torn/damaged.................if so, remove and replace with readily available wrappers (cheap as chips). Many youtube vids to show how easy to fit..........I slip one on the cell, check length which usually is a few mm too long, remove and cut off with scissors. Re fit on the cell, heat with hair dryer(carefully) to shrink wrap on cell.............check all is well and good to go again.

Not into great detail, just keeping it simple like me but those are some basics.

Too add, there are usually lots of warnings even if a flashlight will not flash or blink when close to 3v. Not being able to get into higher modes is a simple indication to charge back up. Ideally, try and not go bellow 3.3-3.5v to keep it within a nice margin of possible...........how will i know when its 3.5v???? Well if a new light, use for a set period, check voltage and repeat to get an idea. For example it may take 2hrs of use to get to 3.5v on medium and turbo uses. So if your uses is simply 30m a day, every 4 days top cell off(just a rough example).


----------



## Dr. Manhattan

@ven Thanks it now feel a little better. Its my first Li-ion battery LED flashlight and I still got the feeling that I have bought a pipe bomb  I have bought a Xtar Ant-MC1 Plus charger and a Keeppower 3500 mah protected battery which should be good quality. The flashlight is a Astrolux S1 which should have necesarry safety mechanisms for example low voltage protection.


----------



## brightex

First of all it is important to understand that Li-ion batteries which you have in every cell phone are an excellent type of battery BUT…they are known to explode or self ignite, as just recently happened with some of the Galaxy Note 7 phones.

Protected Li-ion batteries are batteries which have a circuit board on them which prevents the battery from being reversed charged or reverse operated. Now if you have a charger that is also reverse polarity protected than even if you have a non protected battery it will not be damaged if placed the wrong way in the charger.

Unfortunately there are many low grade batteries and substandard charges sold on the market or supplied with flashlights, so you have to be very careful about the battery that you use and the charger you are using.

Remember there are many products manufactured in China (like iPhone) the difference is where it is made and the specification according to which it was produced.

Our recommendation is to only buy quality protected batteries making sure that the rated capacity (mAh) is the real capacity (In many cases the rated capacity is much higher than the actual capacity). It can be easily verified when testing the battery as per the below picture.





Also make sure you have a quality charger that is UL certified (confirming to the US Safety Standards) there are many dangerous cheap chargers, do yourself a favor and avoid them. Check for the UL marking on your charger. Verify the charging current is at least 1000mA unless you want to wait for hours until your battery is charged! (See below picture)





Here is an article with some additional information on the subject

Good Luck


----------



## HKJ

brightex said:


> Protected Li-ion batteries are batteries which have a circuit board on them which prevents the battery from being reversed charged or reverse operated.



The protection circuit will protect from over discharge, over charge and over current. Reverse operation will trigger one of these protections.



brightex said:


> Verify the charging current is at least 1000mA unless you want to wait for hours until your battery is charged!



That is not a good statement, with 18650 batteries 1000mA is a fine charge current, but it is too high for smaller batteries.



brightex said:


> Also make sure you have a quality charger that is UL certified



That is fine for US, but other countries requires other safety standards.


----------



## sbslider

Looking to find out what a safe resting voltage for a Olight 550mA IMR cell (came with my S1R Baton) is. I have seen several posts that say never let it go below 3.6V resting, but they are all very old. Not sure with the newer batteries that is still true. The light has an indicator that shows when 10-15% capacity is remaining, but not sure if I should rely on that or check the voltage periodically.

Tried finding a chart with resting V vs capacity remaining but no luck.


----------



## markr6

sbslider said:


> Tried finding a chart with resting V vs capacity remaining but no luck.



HKJ did a nice writeup here - http://lygte-info.dk/info/BatteryChargePercent UK.html

See the charts at the bottom. Those are somewhat older cells, but hopefully things are still fairly close.


----------



## sbslider

markr6 said:


> HKJ did a nice writeup here - http://lygte-info.dk/info/BatteryChargePercent UK.html
> 
> See the charts at the bottom. Those are somewhat older cells, but hopefully things are still fairly close.



That article was super helpful. I have seen it before, but I did not really understand the measurement technique until I re-read it again this time. But while being super helpful, it does not answer my specific question. I will start a new thread, as I don't think this is the right place to further this discussion. 

http://www.candlepowerforums.com/vb...-ORB-163C05-IMR-RCR123A&p=5166111#post5166111

thanks, Matt


----------



## Gauss163

sbslider said:


> Looking to find out what a safe resting voltage for a Olight 550mA IMR cell (came with my S1R Baton) is. I have seen several posts that say never let it go below 3.6V resting, but they are all very old. Not sure with the newer batteries that is still true. The light has an indicator that shows when 10-15% capacity is remaining, but not sure if I should rely on that or check the voltage periodically.
> 
> Tried finding a chart with resting V vs capacity remaining but no luck.



First you need to clarify what you mean by "safe resting voltage" and what purpose you will use if for. There are a few possible interpretations.

Maybe you are asking if you can determine if a certain resting voltage implies that the cell was never drained too low in its prior use. That's not always possible to determine, but one could make some guesstimates if you know the (peak) current of the device, the IR of the cell etc.

Or maybe you mean to ask if it is safe to store the cell at that voltage for long periods? Please clarify.


----------



## sbslider

Gauss163 said:


> First you need to clarify what you mean by "safe resting voltage" and what purpose you will use if for.



I will say that my OP was not very clear for what my intent was. I have a Olight S1R, the the included ORB-163C05 IMR RCR123A. My goal is to be able to pick up the light after it has been off for a time, measure the voltage the tail, and decide if I should use it or charge it. In looking into the battery voltage range vs capacity question, I saw several comments that warned to not use a rechargable Li-ion battery that measured less than 3.6V, that it was dangerous. I got a bit caught up in the safety aspect of how low the voltage could go before recharging. Not to dismiss safety, but I am not worried about that in this particular case any more. That's why I started a new thread.

http://www.candlepowerforums.com/vb/...11#post5166111

thanks, Matt


----------



## ven

3.6v sbslider is not too low, that is the nominal voltage , also a good storage voltage(maybe 40-50% capacity. Most cells (variable) have a min voltage of 2.5-2.8v, so to play it a little safer, 3v minimum is a safe voltage to not go bellow(leaves a little room). But even then, if the voltage is bellow the min spec, for example it is 2.3v measured. As long as the cell has not been in this state for a period of time, it should charge up fine(being monitored to add) with minimal issue/potential damage. Most lights do have a built in LVP, also even without the LVP(low voltage protection) not many flashlights will power up at 3v, or certainly not in high modes. As with the load and voltage sag, it will blink or go out letting you know. 

The little RCR123a cells(16340) do not have much capacity, usually 6-700mah in the tank(yours is 550mah ). Its a good idea to use the light and check cell voltage after a few uses. This way you will get an idea of how much use and where the voltage will roughly be. With my 16340 cells, i tend to top off back to 4.2v after use, as even a little use with higher levels(exl low and moon modes) does eat through the mah pretty quick. So by topping them back up to 4.2v, i know exactly where i am up to and good to go again. Now at 3.6v, you dont have that much left, certainly if your going to be attempting higher levels(if the light allow use at that V). If its for regular use, i would certainly carry a spare cell or 2 for the light. If you find your swapping cells out regular, then a compact 18650 light may work better for you. I love 16340 lights, the form for me is perfect for EDC uses, but not ideal for any decent duration. I would struggle in work for example, where a few hours of 200lm( ish as a variable) might be needed. 

3.6v is a good place to top back up yes, but there are no safety issues at that voltage, nor going lower towards 3v. Maybe he was just giving you a large buffer to be extra safe, but i am sure the olight mentioned will not work bellow 3v.


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## sbslider

My testing says 3.6V is about 25% capacity for the battery I am using, Olight ORB-163C05 IMR RCR123A. I ran some testing recently on it, you can see the results here:
http://www.candlepowerforums.com/vb...-ORB-163C05-IMR-RCR123A&p=5166812#post5166812

I use the light mostly at moonlight mode, and on medium. It will last a week or more for me taking nightly walks with my wife, so I really like it.


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## david.allie

Benson said:


> One other useful size you might want to mention was the 17500s; they're 1.5 CR123 cells, so you can stack 2 of them in a 3xCR123 light.
> 
> And that's where the 17500s shine -- 2 17500s at 4.2V starts at 8.4V, whereas 3 primaries @ 3V each start with 9V. Since the Li-ion hold up better under load, they work out great in most such applications.



I admit to being a n00b and know this is an old thread...

I’m not understanding how 2 17500s at 4.2V/each is better and “holds up better under load” than 3 CR123As at 3.0V/each. Would someone explain this to me?


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## lumen aeternum

but show me a 
3xCR123 light


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## david.allie

lumen aeternum said:


> but show me a
> 3xCR123 light



About 3 years ago, I bought the [FONT=&quot]Inova T5-MP Tactical flashlight. It’s a 3 x CR123A light. Works well, too.[/FONT]


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## SilverFox

Hello David.allie,

Welcome to CPF.

I believe you need to review the discharge charts for CR123 cells and 17500 cells. If the voltage remains higher on the 17500 cells, they should perform better.

Tom


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## SilverFox

Hello Lumen aeternum,

The Streamlight 88047 ProTac HL 3 is another light that uses 3X CR123 cells.

Tom


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## xevious

I have just one related question -- is it OK to recharge 2 x RCR123 cells in series? Even if a flashlight maker has produced a flashlight with recharging circuit primarily designed for 18650, but claims it can handle 2 x RCR123 for both output and recharging? I've never seen a dedicated charger support 2 x RCR123 in series, which of course makes sense because it can't detect individual cell status this way... which means one cell might end up overcharged while the other cell is still charging. So I'm presuming that 2 x RCR123 charging in a flashlight is not a good idea, even if a flashlight maker says it is possible.


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## SilverFox

Hello Xevious,

If the cells are closely matched you can get away with charging in series without balancing for awhile. 

One way to deal with this is to make it a practice of charging the R-CR123 cells externally in a charger and just know that if you need to charge inside the flashlight you do have that option.

Tom


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## AirTrainer

If a fully-charged lithium battery (26650) sits idle for 2-4 months subsequent to charging, is there a safety concern? If the battery is sitting within a flashlight with the tail cap partially-unscrewed so as to open the flashlight's circuit, is there a safety concern? If there are two lithium batteries in series within the partially-unscrewed flashlight, is there a safety concern?

I haven't dipped my toes in the lithium battery 'pond' and I'm trying to decide if I'm going to bother. NiMH has been pretty low-maintenance compared to the impressions about lithium I've formed while reading this thread.


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## dragosios

Open-circuit will not drain any battery, single or series.
Overall yes, lithium based ones have a higher energy to weight ratio, but they are more sensitive. Overcharging is a particular concern, but overdischarge will also render them unusable.


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