Panasonic phasing out of Cylindrical Battery Business

[MrAl]

Hello again,

It is starting to sound like i will have to give up my 18650 lights some day. That's too bad because these are some of my favorites.

I dont know if i can upgrade to the 21700 cells because i dont think there is enough WIDTH in my big 7 LED T6 light for example. I think i can accommodate the extra length (about 5mm) but the width might be too great to fit in the chamber and not sure if the middle is thick enough to allow retooling. I'll have to check that.
I know the 21700's are better cells, but if they dont fit you must acquit The flashlight will become moot once your last set of 18650's die off.
From what i have read the 18650's are a little wider than 18mm, closer to 19mm, which means another 2mm in width for the 21700 approximately. I'll do some measurements.

I looked around the web today too and dont see any really good lights that say that they work with the 21700 cells although i do see the cells themselves being sold now.

 

[Jon-LiionWholesale]

Neither Panasonic nor any other top-tier manufacturer will deal with companies who sell directly to consumers. So I am highly skeptical that you are in direct communication with Panasonic on this matter.



None of the top-tier manufacturers have ever endorsed the protected single-cell aftermarket rewraps sold to consumers. Please give some evidence to back up your dubious claim that "the big manufacturers are totally OK with this". This directly contradicts what they have said about such matters, e.g the above-linked cease-and-desist Sony letter that I cited above.

The cease and desist letter is talking about cells without circuitry. Reread it. Protected cells have circuitry and are not standalone cells, but are considered to be completed batteries by the cell manufacturers.

I don't really see why I would lie about this, so your skepticism is very curious. But that's your choice.

 

[Jon-LiionWholesale]

Hello again,

It is starting to sound like i will have to give up my 18650 lights some day. That's too bad because these are some of my favorites.

I dont know if i can upgrade to the 21700 cells because i dont think there is enough WIDTH in my big 7 LED T6 light for example. I think i can accommodate the extra length (about 5mm) but the width might be too great to fit in the chamber and not sure if the middle is thick enough to allow retooling. I'll have to check that.
I know the 21700's are better cells, but if they dont fit you must acquit The flashlight will become moot once your last set of 18650's die off.
From what i have read the 18650's are a little wider than 18mm, closer to 19mm, which means another 2mm in width for the 21700 approximately. I'll do some measurements.

I looked around the web today too and dont see any really good lights that say that they work with the 21700 cells although i do see the cells themselves being sold now.

Don't worry about it. We're talking about Panasonic in particular. There will always be good cell providers in the 18650 size for the foreseeable future.

 

[Gauss163]

The cease and desist letter is talking about cells without circuitry. Reread it. Protected cells have circuitry and are not standalone cells, but are considered to be completed batteries by the cell manufacturers.

I'm afraid you misunderstand. Below I excerpt part of Sony's cease-and-desist letter and elaborate on its meaning.

These [Li-ion] cells were made only to be used in connection with the assembly of battery packs of products such as power tools, which have the necessary enclosure, protective devices and circuitry that enable safe usage of these battery cells. Sony lithium-ion rechargeable battery cells (including those with "VTC" designation) are not intended for use without such packaging or circuitry, and should not be used as a standalone product for instance with e-cigarettes, vaporizer pens or other products of any type.

The use of any Sony lithium ion rechargeable battery cells as a stand-alone product, including with e-cigarettes, vaporizer pens or other products, constitutes a DANGEROUS misuse of the battery cells that poses a SERIOUS RISK of personal injury or property damage. This matter is significant enough that the U.S. Fire Administration, an arm of the U.S. Department of Homeland Security's Federal Emergency Management Agency, released a report ...

The point of the above is that Sony (and every other top-tier) manufacturer does not endorse the use of loose Li-ion cells in standalone products (e.g. 18650s used in vaporizers, flashlights, etc) because there is no way to adequately ensure user safety. This is in contrast to complete professionally designed products where trained engineers have safely integrated Li-ion cells in the power subsystem. Here the engineer has complete control of the design of the battery subsystem so they can ensure that the design meets international safety standards - something that cannot be guaranteed in products using loose cells that are assembled and maintained by the end user.

In case you may not be aware. the safety standards used in designing such systems are extremely comprehensive, designed using fault-tree analysis, FMEA, etc, and incorporating multiple levels of failsafe redundancy. For example, the safety standards employed for laptop batteries consider hundreds of possible safety cases, even the case that a pet urinates on a PC, e.g. below from the IEEE 1625 standard

It is such professionally designed battery subsystems that Sony refers to above. This does not include loose 18650 cells wrapped with a protection circuit by random third-parties. In fact, many knowledgeable folks consider these to be even less safe than loose unprotected cells in various contexts. For example, the metal tab running down the side of the cell increases by an order of magnitude the area where a small metal object can induce an internal short (the tab is positive and the entire cell can is negative) - the cause of many "pants on fire" incidents in the vaping community. Further, there is no protection from mechanical shock, which can easily damage the protection circuit (of which there are many reports) - leaving the user with a false sense of security.

I don't really see why I would lie about this, so your skepticism is very curious. But that's your choice.

No one accused you of lying. As for my choice of what to believe, I'm an (MIT-educated) scientist so, of course, I will choose science and facts over rumors and misunderstandings.

 

[IlluminationDomination]

I'm an (MIT-educated) scientist

"Labels" are indicative of importance.It is the heart that counts where Ego and Pride Cease to Exist.

 

[MrAl]

I'm afraid you misunderstand. Below I excerpt part of Sony's cease-and-desist letter and elaborate on its meaning.



The point of the above is that Sony (and every other top-tier) manufacturer does not endorse the use of loose Li-ion cells in standalone products (e.g. 18650s used in vaporizers, flashlights, etc) because there is no way to adequately ensure user safety. This is in contrast to complete professionally designed products where trained engineers have safely integrated Li-ion cells in the power subsystem. Here the engineer has complete control of the design of the battery subsystem so they can ensure that the design meets international safety standards - something that cannot be guaranteed in products using loose cells that are assembled and maintained by the end user.

In case you may not be aware. the safety standards used in designing such systems are extremely comprehensive, designed using fault-tree analysis, FMEA, etc, and incorporating multiple levels of failsafe redundancy. For example, the safety standards employed for laptop batteries consider hundreds of possible safety cases, even the case that a pet urinates on a PC, e.g. below from the IEEE 1625 standard

It is such professionally designed battery subsystems that Sony refers to above. This does not include loose 18650 cells wrapped with a protection circuit by random third-parties. In fact, many knowledgeable folks consider these to be even less safe than loose unprotected cells in various contexts. For example, the metal tab running down the side of the cell increases by an order of magnitude the area where a small metal object can induce an internal short (the tab is positive and the entire cell can is negative) - the cause of many "pants on fire" incidents in the vaping community. Further, there is no protection from mechanical shock, which can easily damage the protection circuit (of which there are many reports) - leaving the user with a false sense of security.



No one accused you of lying. As for my choice of what to believe, I'm an (MIT-educated) scientist so, of course, I will choose science and facts over rumors and misunderstandings.

Hi,

Very interesting.
I just read the FEMA report, it seems to target the e cigarette applications only.
The main concern seems to be the encasing method due to the "rocketing effect" a cell can have when it ignites.
I believe a lot of flashlights would prevent this from happening even though there could still be a fire. So i think we are good to go, as long as it's a well made strong shell flashlight. All mine are, especially the big one which has thick walls.
The only question i would have for those lights is, where exactly will they vent from then. I have a feeling it would be from the front end where the LEDs are located but i'd have to check to see if they built a firewall between the tops of the batteries and the LED mounting platform.

Most problem cases occurred during use or during charging.
Less than 200 cases over some 8 years and none fatal makes it safer than flying

 

[Jon-LiionWholesale]

I'm afraid you misunderstand. Below I excerpt part of Sony's cease-and-desist letter and elaborate on its meaning.



The point of the above is that Sony (and every other top-tier) manufacturer does not endorse the use of loose Li-ion cells in standalone products (e.g. 18650s used in vaporizers, flashlights, etc) because there is no way to adequately ensure user safety. This is in contrast to complete professionally designed products where trained engineers have safely integrated Li-ion cells in the power subsystem. Here the engineer has complete control of the design of the battery subsystem so they can ensure that the design meets international safety standards - something that cannot be guaranteed in products using loose cells that are assembled and maintained by the end user.

In case you may not be aware. the safety standards used in designing such systems are extremely comprehensive, designed using fault-tree analysis, FMEA, etc, and incorporating multiple levels of failsafe redundancy. For example, the safety standards employed for laptop batteries consider hundreds of possible safety cases, even the case that a pet urinates on a PC, e.g. below from the IEEE 1625 standard

It is such professionally designed battery subsystems that Sony refers to above. This does not include loose 18650 cells wrapped with a protection circuit by random third-parties. In fact, many knowledgeable folks consider these to be even less safe than loose unprotected cells in various contexts. For example, the metal tab running down the side of the cell increases by an order of magnitude the area where a small metal object can induce an internal short (the tab is positive and the entire cell can is negative) - the cause of many "pants on fire" incidents in the vaping community. Further, there is no protection from mechanical shock, which can easily damage the protection circuit (of which there are many reports) - leaving the user with a false sense of security.

OK, yes. What you are saying has nothing to do with the letter though, it seems you misunderstand what is written there. That letter is very clearly and specifically calling out selling loose unprotected cells. Sure, the cell manufacturers prefer applications like what you're saying with a million line DFMEA that includes everything from "pet urination" to "pine martens chewed on the positive wire while standing on the negative wire after taking a bath in saltwater" to "meteorite made of pure copper hits the side of the battery", but that is beyond the minimum required in order to make a battery pack. I'm sure you know that just because a higher standard exists for batteries in a certain application (laptops in the case of IEEE 1625), that doesn't mean every battery in every application has to conform to that standard. "loose cells" means unprotected, in battery speak. That is what the letter is about.

Despite your misgivings about the protected single cell batteries, if designed correctly they are absolutely safer than unprotected cells. They meet the criteria of what the cells are designed for as listed in the letter, having both protective devices/circuitry, and an enclosure (thick PVC) protecting from short circuits. I would understand if you disagree that they're safer due to the potential issues you posted but you would be in the minority there, and for sure it cannot be said that the letter is trying to address these single cell battery packs.

I may have graduated from Penn State and not MIT, but I am an engineer who is actually working in this industry who is also obsessed with science and facts and would never share information where the truth is not 100% certain. So I understand where you're coming from with wanting to make sure this isn't rumor, but I think you're mistaken that your disagreement comes from facts in this case.

 

[WalkIntoTheLight]

I think you have to realize that safety standards are designed to protect the most stupid people in society, and those who have been permanently cursed by voodoo witch-doctors. Hopefully, none of us would do incredibly dumb things to our 18650 lights or cells. If you use them as intended, they'll be safe. Be an idiot, and they'll be unsafe.

 

[Gauss163]

OK, yes. What you are saying has nothing to do with the letter though, it seems you misunderstand what is written there. That letter is very clearly and specifically calling out selling loose unprotected cells.

The scope of the letter is most certainly not restricted only to unprotected (single) cells. Please read it more closely.

Sure, the cell manufacturers prefer applications like what you're saying with a million line DFME ... I'm sure you know that just because a higher standard exists for batteries in a certain application (laptops in the case of IEEE 1625), that doesn't mean every battery in every application has to conform to that standard. "loose cells" means unprotected, in battery speak. That is what the letter is about.

They don't "prefer" packs that meet safety standards. Rather they insist on such - as is made clear in the Sony letter I posted. You seem to misunderstand the gist of the letter.

Despite your misgivings about the protected single cell batteries, if designed correctly they are absolutely safer than unprotected cells. They meet the criteria of what the cells are designed for as listed in the letter, having both protective devices/circuitry, and an enclosure (thick PVC) protecting from short circuits. I would understand if you disagree that they're safer due to the potential issues you posted but you would be in the minority there, and for sure it cannot be said that the letter is trying to address these single cell battery packs.

As I emphasized in a prior post, single cells with protection circuits added by random 3rd parties have many deficiencies. They have never been endorsed for general public use by any reputable / top-tier manufacturer. Nor will they ever be, since they are far from meeting the safety of professionally designed battery packs. Claims to the contrary are common by low-tier (Chinese) rewrappers - who clearly don't give a damn about the safety of their users. It is sad to see such unfounded claims being propagated even further by some USA sellers.

I'm not sure if you are serious or joking about the "thick PVC enclosure" sheathing protected cells. In case you are serious, you should be aware that the thin PVC wrapper on protected cells is often ripped open when used by hobbyists, and it most certainly does not suffice as the sort of "enclosure" mentioned in Sony's letter. An adequate battery (pack) enclosure must not easily be breached and must also protect the circuitry from mechanical shock. You don't have to read very far in vaping or flashlight forums to see how poorly that "thick PVC enclosure" performs in this regard. Its frequent failure is one of the primary causes of accidents reported by hobbyists.

Given that you are selling Li-ion cells directly to the public I encourage you to learn more about safety matters, and use that knowledge to help educate your buyers. The little safety warning blurb that you append on your web pages is far from adequate in this regard (e.g. it does not even mention why Li-ion cells pose a much higher risk of shorts vs. other common consumer cells - one of the primary sources of accidents).

 

[Gauss163]

I think you have to realize that safety standards are designed to protect the most stupid people in society, and those who have been permanently cursed by voodoo witch-doctors. Hopefully, none of us would do incredibly dumb things to our 18650 lights or cells. If you use them as intended, they'll be safe. Be an idiot, and they'll be unsafe.

But use of Li-ion cells is now ubiquitous due to the popularity of vaping. Moreover the ability to safely use Li-ion cells requires more than just intelligence. It also requires the discipline to religiously follow safety rules. Otherwise the one time you get lazy you may end up like the hobby shop owner who left his pack unattended for 10mins and it burned down his shop.

Properly designed Li-ion devices help cover our *** when we make the inevitable human error - whether it be from lack of safety knowledge, laziness, etc.

 

[WalkIntoTheLight]

But use of Li-ion cells is now ubiquitous due to the popularity of vaping. Moreover the ability to safely use Li-ion cells requires more than just intelligence. It also requires the discipline to religiously follow safety rules. Otherwise the one time you get lazy you may end up like the hobby shop owner who left his pack unattended for 10mins and it burned down his shop.

Properly designed Li-ion devices help cover our *** when we make the inevitable human error - whether it be from lack of safety knowledge, laziness, etc.

There's also examples of laptops burning down shops when left unattended and plugged in. I don't rely on safety mechanisms protecting me from problems. I make sure never to charge any lithium-ion device (or loose cells) when I'm not home or when I'm sleeping.

During charging is really the only time I'm paranoid of lithium-ion batteries. During use, or sitting idle, they shouldn't cause a safety issue unless there's something wrong (like a short). Measure voltage before and after charging, and you should be good to go. Yeah, there is a very rare chance of a cell catching fire for no reason, but there are way more dangerous things in life.

For lazy people (or newbies), I always recommend Eneloops.

 

[MarioJP]

While that incident happened 2015. Hopefully by now people have learned that liion is not to be taken lightly. What is interesting enough that not many consumers even know what is a 18650, at least from what i have encountered.

And the other half of it is knowing where to buy these cells. I do not trust Ebay or even Amazon when it comes to buying liion's. Oh and those ultrafires claiming 9800mAh. How are these allowed to sell?? That should be illegal for false advertisements and putting users at risks.

How are these sellers in question are able to continue doing business knowingly these cells are a dud.

 

[Gauss163]

There's also examples of laptops burning down shops when left unattended and plugged in.

Alas, even the best protection circuits can't help much in the case of internal shorts (one of the major causes of such problems). But there are improvements (ceramic separators, heuristic prediction of impending shorts, etc) which have helped minimize such risks compared to early times.

I make sure never to charge any lithium-ion device (or loose cells) when I'm not home or when I'm sleeping.

That's one of the primary safety rules for Li-ion.

 

[iamlucky13]

I think we're getting a bit off track here. Lithium ion safety is and should be a perennial topic, but the focus of this discussion was the current and future availability of Panasonic cylindrical cells.

Between what we know about Panasonic and what Jon from Liion Wholesale says he has been told, plainly cylindrical cell production continues. It seems reasonable to accept that supply for small quantities of Panasonic cells is tight and should be expected to remain so. And Panasonic is likely to continue to discourage or perhaps even try to more actively prevent 2170 cells from being sold this way.

One part of the discussion I was curious about was Jon's comment:

Those automotive cells are very unlikely to get out onto the open market and also are unlikely to be suitable for flashlight use for various reasons. Mainly, many of them will be prismatic style, not cylindrical. Even the Tesla 2170 is not something I would ever recommend using outside of a system designed for it. So for the purposes of where flashlights are concerned, they seem to be phasing themselves out of the market.

Why do you consider the 2170 less suitable for flashlights than the 18650 or 26650 cells already widely in use? Does that opinion apply even to a notional protected 2170 cell?

 

[IlluminationDomination]

^^^
He obviously can speak for himself. But I think the answer or at least part of is in the quote of his that you provided.


Mainly, many of them will be prismatic style, not cylindrical.

 

[nbp]

Thank you ~iamlucky13. Yes, please let's stay on topic. There are other threads for battery safety.

 

[Jon-LiionWholesale]

Why do you consider the 2170 less suitable for flashlights than the 18650 or 26650 cells already widely in use? Does that opinion apply even to a notional protected 2170 cell?

I'll answer this one just to wrap up the discussion.

I'm specifically talking about the Tesla 2170. Not the 21700 cells being made for non-Tesla use. Other 21700s in general, for example the ones we and others are selling, would be expected to be the same level of risk/safety as the 18650s.

I'm not very informed about the 2170 specifically since not much information has been released and on this front I don't know any more than anyone else, so this could be an incorrect guess, but in general Tesla has always pushed for a minimum of safety features in their cells, preferring to do external safety protections in the pack instead. Even unprotected cells do have some safety features built in which I expect the Tesla cells are probably missing some or all of them based on their past design decisions.

Now hopefully we can get back on topic .

 

[HighlanderNorth]

I heard that Panasonic most certainly will not be producing 48940 batteries. But it's also likely that they never planned on making 48940's to begin with.... Lol

 

[snakebite]

afaik none of the high rate cells have ptc,fuse leads,tearoff tabs,ect.
if you short them bad things happen quickly.
protection hinders these type of cell too much.
thats why tesla uses cell level fuses.
as to panasonic stopping production of other cylindrical cells the writing has been on the wall a while.
they are fading fast due to all newer laptops moving to flat lipo.

I'll answer this one just to wrap up the discussion.

I'm specifically talking about the Tesla 2170. Not the 21700 cells being made for non-Tesla use. Other 21700s in general, for example the ones we and others are selling, would be expected to be the same level of risk/safety as the 18650s.

I'm not very informed about the 2170 specifically since not much information has been released and on this front I don't know any more than anyone else, so this could be an incorrect guess, but in general Tesla has always pushed for a minimum of safety features in their cells, preferring to do external safety protections in the pack instead. Even unprotected cells do have some safety features built in which I expect the Tesla cells are probably missing some or all of them based on their past design decisions.

Now hopefully we can get back on topic .

 

[MrAl]

Hello again,

I had not figured the non cylinder cells into the picture yet. That's worse yet. I am almost sure that my bigger light would need a very big mod to get it to work with the new cells that are not cylindrical. It would need the part of the light that holds the batteries to be enlarged or something and shaped so that it holds the cells properly and makes good contact with the top contact area.
This would require significant rework of the main body of the light, just not the head.
Since the body screws on, i would need a lathe that could handle around 2.5 inch diameter pieces, and since i dont have that i would have to find another way like maybe bolt a new body onto the head. Probably tap and thread the head to accept machine screws, like 3 or 4 of them. Maybe then make the bottom come out to replace/charge the cells.

Deserves much more thought though. Maybe start a thread about this kind of thing, for different kinds of lights?