# Why Not Use Rechargeable Batteries?



## Nephron44 (Jan 24, 2019)

Hey everyone!

At work I find myself using AAA lights most often, and I burn through batteries very quickly.

I mainly use Streamlight, ASP, and Maglite AAA lights. I recently picked up some Energizer and Eneloop rechargeable batteries with a nice charger to hopefully save some cash on batteries.

I contacted Streamlight, Maglite, and ASP to ask about the use of rechargeable batteries. So far only Streamlight replied, and they informed me that rechargeable batteries should not be used as they are a fire hazard and can damage the light.

If lights from Fenix, Surefire (Titan series), and other brands can tolerate rechargeable batteries, why is it such a big deal to use them in a Streamlight, ASP, or Maglite. I should add that in my particular lights, Streamlight and ASP indicate that lithium batteries can safely be used.

Can someone please enlighten me why rechargeable batteries should not be used?

Thanks!


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## Timothybil (Jan 24, 2019)

Did you specifically say you were asking about the use of NiMH cells? It is almost impossible to set an NiMH cell on fire, but is a lot easier to do with LiIon cells.
I am using NiMH cells in almost all of my AA and AAA lights without any problems, other than they don't have the capacity of lithium primary cells. I won't use alkaline cells for anything. I have lost too many lights to alkaline leakage.


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## nimdabew (Jan 24, 2019)

The flashlight companies also sell primary batteries. Food for thought.


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## Nephron44 (Jan 24, 2019)

Timothybil said:


> Did you specifically say you were asking about the use of NiMH cells? It is almost impossible to set an NiMH cell on fire, but is a lot easier to do with LiIon cells.
> I am using NiMH cells in almost all of my AA and AAA lights without any problems, other than they don't have the capacity of lithium primary cells. I won't use alkaline cells for anything. I have lost too many lights to alkaline leakage.



I specifically stated the type and brand in my inquiry. It is reassuring that you have had a good experience with using rechargeable batteries!


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## Nephron44 (Jan 24, 2019)

nimdabew said:


> The flashlight companies also sell primary batteries. Food for thought.



Good point...


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## Sos24 (Jan 24, 2019)

I use rechargeable batteries in almost all my lights. The only issue I have ever had is that certain lights cannot handle the higher voltage li-ion. I have never had a problem with Ni-Mh.


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## martinaee (Jan 24, 2019)

To be fair isn't it only very recently that Surefire brought 18650 lights into their lineup? That's only been the case for several years. From what I remember hearing on CPF in the past they have military contracts for things like CR123 cells so of course they weren't eager to introduce lights with rechargeable lithium cells into their product lines.

I have a box of 12 Surefire CR123 cells for emergencies, but even in my yellow G2X Pro I use a couple 16650 cells. No use burning through those primaries just going for night walks


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## WalkIntoTheLight (Jan 24, 2019)

nimdabew said:


> The flashlight companies also sell primary batteries. Food for thought.



^^^ This ^^^

However, there's also a possibility that you can burn out the flashlight if the light is really badly designed. Some really crappy lights depend on the internal resistance of alkaline batteries to limit the current to the LED. In that case, using a NiMH with a low internal resistance (like an Eneloop) could overdrive the LED and cause it to burn out prematurely.

IIRC, Maglite used to specifically warn against using NiMH in their LED lights, for that very reason. Hopefully, they've improved.

I've never had a problem using Eneloops in a light designed for alkalines, even the really cheap ones. But, I've never used them for very long, so YMMV.


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## BB (Jan 24, 2019)

Many higher end lights are pretty much gas tight (O-rings and rubber switch boots). And NiMH batteries can gas hydrogen if shorted:

https://www.panasonic.com/global/consumer/battery/eneloop/technologies.html



> [FONT=&quot]Please do not use eneloop Ni-MH batteries in underwater lights or other airtight appliances. Ni-MH batteries feature a gas vent that allows the release of hydrogen when the battery is misused. Gas will not be released under normal usage conditions, but hyper-electric discharge or short circuit can cause internal gas pressure to rise and gas to be expelled. This gas contains hydrogen and sealed devices can’t diffuse the gas, so any source of ignition may potentially cause fire.[/FONT]



http://www.candlepowerforums.com/vb/showthread.php?243109-Eneloop-s-safe-in-Waterproof-lights

That would be my guess why some mfg. are saying no to "rechargeables" and/or NiMH specifically.

-Bill


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## BB (Jan 24, 2019)

I should also add that some of the intrinsically safe rated flashlights have a catalyst and 0 psi vent to address these types of issues:

https://www.thefirestore.com/store/...n-Flashlight-and-Universal-Helmet-Clip-Combo/



> Hydrogen scrubber catalyst, polarized battery contacts and 0-psi vent minimize explosive risk from leaking batteries



-Bill


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## Chauncey Gardiner (Jan 24, 2019)




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## Kestrel (Jan 24, 2019)

Back in the day, shorting a NiCad cell was an adventure that flashlight companies probably still worry about somehow.

If there was any justice in this world, Eneloops should have completely taken over the market from all other non-lithium chemistries 10+ yrs ago ... :-/


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## WalkIntoTheLight (Jan 24, 2019)

BB said:


> Many higher end lights are pretty much gas tight (O-rings and rubber switch boots). And NiMH batteries can gas hydrogen if shorted:
> 
> https://www.panasonic.com/global/consumer/battery/eneloop/technologies.html
> 
> ...



While that may be true (though I've never heard of it occurring), it's a pretty insignificant risk. And anyone that uses any kind of lithium-ion powered device (smart phone, etc), has already decided to accept a far greater battery risk (though still pretty small).

Eneloop does state right on the package not to use their batteries in sealed devices like flashlights. That's lawyer CYA speak.


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## Berneck1 (Jan 25, 2019)

I use Eneloops in all of my flashlights. Never had an issue. And I agree, it’s the lower quality technology that may have the issue. In fact, many of the lights I have specifically state that the runtime specs are when using NiMh batteries...


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## xevious (Jan 25, 2019)

Kestrel said:


> Back in the day, shorting a NiCad cell was an adventure that flashlight companies probably still worry about somehow.
> 
> If there was any justice in this world, Eneloops should have completely taken over the market from all other non-lithium chemistries 10+ yrs ago ... :-/


Yep. We have to remember that companies are always coming from a legal accountability perspective. Even if the chances of a danger with rechargeable NiMH cells is negligible, they'll still warn about them to self-absolve of any legal implications. If a flashlight company does very extensive testing to prove their design is totally safe, a battery failure should implicate the battery maker, not the flashlight maker. In this age of prolific exploitative litigation, one has to safeguard against potential abuse... It's pretty disgusting how ugly it is, where power of money significantly affects outcome of justice.

Bottom line, we can ignore such disclaimers and make sure to be an educated flashlight owner. Know your tools and your power sources.


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## xxo (Jan 25, 2019)

Why would a flashlight manufacture recommend a battery for an application (sealed watertight flashlight) that the battery maker (eneloop) specifically warns against?


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## Kestrel (Jan 25, 2019)

xxo said:


> Why would a flashlight manufacture recommend a battery for an application (sealed watertight flashlight) that the battery maker (eneloop) specifically warns against?


Because there is nothing better for lawyers' paychecks than a well-funded opposing side. :-/


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## BB (Jan 25, 2019)

It does happen... And happened to ~4 people here on CPF (from my above post):

http://www.candlepowerforums.com/vb/showthread.php?243109-Eneloop-s-safe-in-Waterproof-lights

Thread from 2010. Nobody had any explosions (mostly inflated switch boots)... And I had an alkaline battery pressurize my Arc AAA flashlight a decade ago too (very difficult to unscrew the head).

Stuff happens. How much energy from a hydrogen "explosion" would be in a AA tube flashlight with 2 NiMH batteries (not much free air space) vs a diving light with a larger amount of "air space". Add pressurization (more H2 in confined space)--Don't know. Enough of an issue that some mfgs. installed catalyst and one way vents in their 4 AA and larger lights to get Class ratings. 

-Bill


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## Kestrel (Jan 25, 2019)

~8 yrs ago, when I got my mint SF 7Z:
https://www.dropbox.com/s/9oh2wul8pn5lc0d/SF 7Z 003.jpg?dl=0

I found it interesting that SF had factory-drilled a tiny vent hole near the tailcap:
https://www.dropbox.com/s/v3vabo50xw7vxd3/SF 7Z 025.jpg?dl=0

(The 7-series being comparable to the 6R series - which were designed for SF's proprietary B?65? NiMH battery pack.)


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## BRubble (Feb 4, 2019)

Nephron44 said:


> Hey everyone!
> 
> At work I find myself using AAA lights most often, and I burn through batteries very quickly.
> 
> ...



Nephron,

Why Not Exactly.

I'm in the process of switching as many of my Battery Light's over to Rechargeable that I can. In my Home,, I've got 5 rechargeable Flashlight's plugged into the Wall Socket's that are fully charged if I need one,, and when the electricity goe's off the Light's will auto come on. I'm pretty sure that they are Lithium Ion Batterie's. My Cordless Groomer use's Rechargeable AA 1.2V 2800 Micro Amp Capacity NiCd's , so far so good. If you can find a Light with a built in Charger that use's the AA Size Rechargeable NiCd's with a Bright LED that might be a good Ticket.

Out in the Garage I've got a Dewalt worklight that uses Rechargeable NiCad's. I have one of the DeWalt Charger Radio's that has a Smart Charger that once the Battery is Charged, the Charger will shut off and monitor the Battery. The NiCd Battery can be left in the Radio Charger so that I'll have a fully charged Battery when I need it for my Driver's or the WorkLight. I've read enough about the Nimh's and Review's that I don't think that they are as good as the NiCd's or Lithium Ion's.

DeWalt as well as other Brand's have Smart Charger's also for Lithium Ion Batterie's.

Check out EBay & Amazon, You might find the Right Flashlight with the Lumen's that you need that are Rechargeable or one of the Tool Brand Work Light's, might have a Rechargeable LED Light that is the size, shape, and Lumen's to fit your need.

If you can find a WorkLight that will fit your need's, that might be your best bet,, cause if the Worklight isn't any good the word spread's fast not to buy that Light and Vice Versa.

Good Luck


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## alpg88 (Feb 4, 2019)

depends on a light, some may not like lower voltage of nimh. most may have no issues, idk about surefires but maglites are not airtight. head-tube thread is a bit lose, and o ring can't stop gases under pressure. rain even submerging in few feet of water is different, i had 6d maglite in my car when it was flooded by sandy, not a drop inside. but it was in maybe few feet of water for half a night.


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## fivemega (Feb 4, 2019)

Nephron44 said:


> Can someone please enlighten me why rechargeable batteries should not be used?


*In most cases (NOT ALL) you can use proper rechargeable batteries instead of alkalines.
Big companies don't want to involve legal issues and don't approve usage of rechargeables.
So please educate yourself with all primary and rechargeable batteries then use them safely.*


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## Gt390 (Feb 5, 2019)

I have had alkaline batteries leak so badly that the head of the light popped off like a champagne cork. This has never occured with eneloops. I would say venting is more of a worry with a regular old alkaline than anything else.


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## Gt390 (Feb 5, 2019)

Should have said vent not leak. Although they do like to leak also.


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## Monocrom (Feb 15, 2019)

I've very recently warmed up to using rechargeables of all sorts. In the past, I hated them as all but one flashlight failure I've experienced was due to rechargeable batteries letting me down. As far as flashlight makers go, it's just easier to optimize lights to run off of one type of battery. Usually non-rechargeable primaries. Though nowadays, more and more companies are making dual options for both primaries and rechargeables. Though unless specifically stated as made for both, it's just easier to either use lights that are; or only use primaries.


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## xxo (Mar 8, 2019)

From Mag's FAQs:

*"You recommend alkaline batteries for use in all of Mag’s AAA, AA, C and D-cell flashlights. But I would prefer to use rechargeable batteries (NiMH) if I can. Is there any reason why NiMH rechargeable batteries can’t be used in these lights?*

With the exception of the MAG-TAC® flashlight that runs on lithium CR123 batteries, all of Mag’s non-rechargeable LED flashlights operate on AAA, AA, C or D-cell batteries. All of our published ANSI-standard performance data (Light Output, Beam Distance, Peak Beam Candlepower and Run Time) are based on testing with alkaline batteries; and when we ship these flashlights with batteries, the batteries we include with them are alkaline. We do this because the designs of these flashlights are optimized for use with (non-rechargeable) alkaline batteries.
Alkaline AAA, AA, C and D batteries standardly have a nominal output of 1.5 volts. NiMH rechargeable batteries in these sizes typically have a somewhat lower nominal output (1.2 volts). Also, the discharge curves of NiMH batteries typically differ from those of alkaline batteries – so the two battery types may behave differently under load.
That said, the flashlights will operate with NiMH rechargeables, and use of NiMH rechargeables will not harm the circuitry nor otherwise damage the flashlights in any way. You should not, however, expect the flashlights’ performance to be consistent with our published ANSI data if they are operated with rechargeable batteries. (For example, ANSI Light Output may be lower, and/or ANSI Run Time may be shorter with rechargeable batteries.) The degree of difference is hard to predict. We have noted variation in the quality of NiMH rechargeable batteries on the market, and if you choose the best-quality NiMH batteries you might find that any performance shortfall is, for your purposes, not meaningful.
Bottom line, if you are willing to tolerate a possibly significant decline in flashlight performance, there is no reason you can’t substitute rechargeable NiMH batteries for (non-rechargeable) alkalines."


https://maglite.com/support/faq


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## menowantsmellyfish (Mar 8, 2019)

I had just read that on the Maglite website. I am a big Maglite fan for decades (call me old school), I just don't like buying Chinese mass produced lights even if they are quality products. About two years ago I started using NiMh, first Rayovac then Eneloop. I find that the performance as far as how long the batteries last is way shorter than with fresh Duracells. Also, maybe not quite as bright. To me, this is a good trade off as buying boatloads of batteries is expensive and not good for the environment. Since I use these light for work and they get used a lot it makes sense. Add to this, that I had destroyed two Maglites one AA and one 3 D by leaky alkaline batteries. Another AAA was damaged but I saved it. This is almost a good enough reason to use NiMh. 

On a side note, I was wondering if anybody had better performance with eneloop Pro (black). The run time on the regular AA LED is not bad, but on the very demanding Maglite Pro LED I constantly have to swap out batteries.

Thanks


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## xxo (Mar 8, 2019)

menowantsmellyfish said:


> On a side note, I was wondering if anybody had better performance with eneloop Pro (black). The run time on the regular AA LED is not bad, but on the very demanding Maglite Pro LED I constantly have to swap out batteries.
> 
> Thanks




Pros work great, I have some xx's from when they first came out (they were originally called xx before they started calling them pros), plus a bunch of rebranded pros in the form of Duracell Ion Cores and the high capacity Fujitsu "Fujiloops" with black labels - expect about 20-30% extra capacity/run time with these over the standard capacity Eneloops.


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## menowantsmellyfish (Mar 8, 2019)

xxo said:


> Pros work great, I have some xx's from when they first came out (they were originally called xx before they started calling them pros), plus a bunch of rebranded pros in the form of Duracell Ion Cores and the high capacity Fujitsu "Fujiloops" with black labels - expect about 20-30% extra capacity/run time with these over the standard capacity Eneloops.



Sounds good, I just have to be careful where I get them. I got some from Ebay a while ago and they turned out to be fakes.


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## bykfixer (Mar 9, 2019)

The eneloop brand was devised to be an alternative to alkaline batteries when it came time to toss them into the trash. Being they were rechargeable made it so the need to tossing them in the trash took a lot longer than single use type. Storage life was also miraculous compared to the rechargeable aa and aaa of the day. Yet supplied voltage was such that they did not damage equipment such as cameras and flashlights. 

For years camera stores sold them by the bushel. But along came the virtual extinction of the camera store and along with it Eneloops from a physical store. When Radio Shack and Circuit City collapsed, another source was gone. 

In many cases rechargeables send higher output to a device such as a Maglite and may over heat internals over time. One thing not covered is in cases of life or death a low voltage circuit can cause unexpected darkness. That is why some companies speak against using rechargeables. And don't forget those "exploding battery" stories you see from time to time. 

But if a light can run off an ultimate lithium cell, it will be fine with one of the Eneloop models. I prefer Pro's myself. Runtimes in regulated lights is great and sag while used in direct drive lights is greatly reduced.


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## xxo (Mar 9, 2019)

menowantsmellyfish said:


> Sounds good, I just have to be careful where I get them. I got some from Ebay a while ago and they turned out to be fakes.



Newegg seems to be a good source for Fujiloops and they run sales on them fairly often. You can also get rebranded Eneloop Pros from brick and mortar stores in the form of Duracell Ion Cores or Energizer Recharge Plus (the ones made in Japan). Ikea's Laddas are also apparently rebranded Eneloop pros.


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## bykfixer (Mar 9, 2019)

Good info double x.


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## menowantsmellyfish (Mar 9, 2019)

xxo said:


> Newegg seems to be a good source for Fujiloops and they run sales on them fairly often. You can also get rebranded Eneloop Pros from brick and mortar stores in the form of Duracell Ion Cores or Energizer Recharge Plus (the ones made in Japan). Ikea's Laddas are also apparently rebranded Eneloop pros.



Not sure about the Duracell Ion Cores or Energizer, but I had read somewhere that the Ikea are in fact Eneloops but they are seconds (rejects) that they buy in bulk and relabel. You usually get what you pay for.


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## xxo (Mar 9, 2019)

menowantsmellyfish said:


> Not sure about the Duracell Ion Cores or Energizer, but I had read somewhere that the Ikea are in fact Eneloops but they are seconds (rejects) that they buy in bulk and relabel. You usually get what you pay for.



I don't have any ladda's but they seem to be pretty much the same as the Eneloops and others in HKJ's tests:

Ladda - 

http://www.candlepowerforums.com/vb...w-of-Ikea-Ladda-AA-2450mAh-(White)-703-038-76

Eneloop -

http://www.candlepowerforums.com/vb...Review-of-Eneloop-AA-HR-3UWXB-2450mAh-(Black)

Duracell - 

http://www.candlepowerforums.com/vb...w-of-Duracell-AA-Ultra-2400mAh-(Green-Copper)


Fujitsu -

http://www.candlepowerforums.com/vb...Review-of-Fujitsu-AA-HR-3UTHC-2450mAh-(Black)


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## Curious_character (Mar 11, 2019)

I'm using Eneloop cells in everything I own which uses AA or AAA cells, from clocks and TV remotes to flashlights and aviation headsets. I simply got tired of opening something and finding corrosive goo all over -- when it isn't welded shut by the goo, that is. For a long time, it wasn't practical for very low drain devices because of the high self discharge rate of NiMH cells, but it is now. Guess I've been lucky -- I've never experienced any pressurization of air tight devices. But there are two policies I follow religiously:

1. I'm fussy about where I get my Eneloops. There are lots of counterfeits out there.
2. From the time they're new, I keep cells together that are used together -- I have single cells, sets of two, three, four, and more that always stay together.

I've been changing over rectangular 9 volt batteries to rechargeables, too -- mostly Li-ion but some NiMH.

I'll never go back to leaky alkalines.

People who worry about the nominal voltage difference between alkaline and NiMH cells should read this: http://eznec.com/Amateur/1.5_vs_1.2_Volt_Batteries.pdf.

c_c


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## Sabrewulf (Mar 11, 2019)

I've been using eneloops for quite some time and never had issue with them. 

I use them in all my devices except my modified lights and larger lights.


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## xevious (Mar 14, 2019)

xxo said:


> Newegg seems to be a good source for Fujiloops and they run sales on them fairly often. You can also get rebranded Eneloop Pros from brick and mortar stores in the form of Duracell Ion Cores or Energizer Recharge Plus (the ones made in Japan). Ikea's Laddas are also apparently rebranded Eneloop pros.


What's the "official" name of the "Fujiloop" batteries that are re-wrapped Eneloop Pro?
EDIT: Fujitsu AA: HR-3UTHC, AAA: HR-4UTHC

Btw, beware of Amazon ripoffs. The Ikea LADDA batteries are sold there at just under $20 for a pack of 4. Ikea sells then on their website for $6.99 per 4/pack. But shipping is a whopping $9. So better to buy more than one or added to another order.


What's interesting is that there seems to be a new breakthrough on charge cycles. The standard for most NiMH has been 500 cycles, but now some brands are achieving 2000 cycles and even as high as 5000 cycles.


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## Curious_character (Mar 20, 2019)

xevious said:


> What's the "official" name of the "Fujiloop" batteries that are re-wrapped Eneloop Pro?
> EDIT: Fujitsu AA: HR-3UTHC, AAA: HR-4UTHC
> 
> Btw, beware of Amazon ripoffs. The Ikea LADDA batteries are sold there at just under $20 for a pack of 4. Ikea sells then on their website for $6.99 per 4/pack. But shipping is a whopping $9. So better to buy more than one or added to another order.
> ...


I think it's more likely that some brands are *claiming* that many cycles. I believe that as much as I believe claims for battery capacity and flashlight lumen output. Genuine Eneloops are just about the only cells I've ever found that actually have their claimed capacity. But I've never measured the number of cycles they're good for, and I doubt that anyone has actually measured the number of cycles claimed by those other amazing cells.

c_c


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## WalkIntoTheLight (Mar 21, 2019)

Curious_character said:


> I think it's more likely that some brands are *claiming* that many cycles. I believe that as much as I believe claims for battery capacity and flashlight lumen output. Genuine Eneloops are just about the only cells I've ever found that actually have their claimed capacity. But I've never measured the number of cycles they're good for, and I doubt that anyone has actually measured the number of cycles claimed by those other amazing cells.



Those claims (including Eneloops) are based on _partial_ cycles, not full cycles, and modest current demands. Partial charging and discharging is a lot easier on the cells. It's probably closer to what most people do in practice, though, so I suppose it's not that misleading.

AA Cycler has done some tests on Eneloops with full cycles and more demanding charging and discharging. Based on his tests, it seems like you get 300-400 "good" full cycles from Eneloops, before their internal resistance starts to skyrocket, and the capacity starts to slowly drop. After that, they're still usable, but for lower-drain applications. I have a few Eneloops in that condition.

Other brands, I imagine you get a lot less cycles than that.


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## Cosmodragoon (Mar 24, 2019)

I invested in a bunch of Eneloop Pro batteries last year and I've been happy with their performance so far. More recently, I bought some of the regular white Eneloops to use in wall clocks, TV remotes, and the Sofirn C01. I don't know if this is correct or if it really matters but I saw some discussion that the white ones can hold up better in the long term for those devices.

With all the alkaline batteries I'm not buying now, I'll break even by next year. With the knowledge that I won't get stuck without batteries and won't have to remember to buy more at the store, I'm already ahead.

As others have said, Eneloops are very safe and won't ruin devices the way alkaleaks can.


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## fred flinstone (Jan 23, 2022)

Realize this is an old thread but recently I made the same inquiry to Surefire concerning one of their lights, 
I needed a certain dia size, they had it but only feed with alkaline or lithium, I asked why and was told the fancy electronics that kept the light at a steady output and multifuctional was engineered for 1.5 volts and would fry at 1.8 which I was told most rechargeable put out fresh. 

I would assume (not an engineer), that with all the multiple function led beamers out there, and the tiny working space on board this is probably a pat reason. hope this helps someone who looks here first. If they state there is a special feed, probably best stick with it.


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## Lynx_Arc (Jan 24, 2022)

fred flinstone said:


> Realize this is an old thread but recently I made the same inquiry to Surefire concerning one of their lights,
> I needed a certain dia size, they had it but only feed with alkaline or lithium, I asked why and was told the fancy electronics that kept the light at a steady output and multifuctional was engineered for 1.5 volts and would fry at 1.8 which I was told most rechargeable put out fresh.
> 
> I would assume (not an engineer), that with all the multiple function led beamers out there, and the tiny working space on board this is probably a pat reason. hope this helps someone who looks here first. If they state there is a special feed, probably best stick with it.


1- Alkaline AA = 1.5-1.6v
2-Energizer Lithium AA primaries 1.8v (non rechargeable)
3-Nimh rechargeable AA 1.4v
4-Lithium ion rechargeable 3.7v (4.2v off the charger)

In other words Eneloops or other nimh should work and lithium primaries may work fine too as the voltage does drop under load.


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## bykfixer (Jan 24, 2022)

I too am not an engineer but having read it a few times, I believe some products are designed to work around the cushion of batteries under load. Example is the alkaline states 1.5 volts but largely produces 1.2 volts under load. It's why Maglite still reccomends alkalines. Especially their max bright models that already get pretty warm when fed by alkaline batteries.

I use eneloop pro's in a super sucker, direct drive coast number simply so it can run 10 minutes or so without a noticeable drop in output. With regular eneloops and alkalines you can actually see it dimming within about a minute. If used a minute or so here and there it's not so bad but for an extended period that thing fades mighty fast.

Some lights may not be designed for the steady outout of the ultimate lithium or eneloop pro. Those dime store type lights for example. But the standard eneloop type battery is becoming more readily available thanks to a plethora of solar charged items like yard lights.


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## Monocrom (Feb 10, 2022)

fred flinstone said:


> Realize this is an old thread but recently I made the same inquiry to Surefire concerning one of their lights,
> I needed a certain dia size, they had it but only feed with alkaline or lithium, I asked why and was told the fancy electronics that kept the light at a steady output and multifuctional was engineered for 1.5 volts and would fry at 1.8 which I was told most rechargeable put out fresh.
> 
> I would assume (not an engineer), that with all the multiple function led beamers out there, and the tiny working space on board this is probably a pat reason. hope this helps someone who looks here first. If they state there is a special feed, probably best stick with it.


Honestly, as great as SureFires are (and I've got just over two dozen around me as I type this) if a company simply doesn't offer what you need, go with one that does. Plenty of members on CPF have used rechargeable lithiums in SureFires that SF swore would fry the bulbs or the LEDs. They had no issues, but a few members did. Nothing is set in stone. Just realize the risks if you choose to do the same. 

Personally, to me it's just not worth it and I'd go with a different brand. Honestly, despite being a SureFire fan-boy myself, I can't pretend that there aren't brands out there making lights that are extremely durable and reliable. In terms of durability, maybe not quite to SureFire levels. But certainly close enough that pragmatically speaking, it's a non-issue.


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