Single lithium cell safety and questions

Hello,

I read most lithium/li-ion safety thread in this subforum and I thought to stay away from anything more then single cells configurations to be really safe.

Anyway everytime I read about a battery accident I get more doubts about lithium technology. I would still have many question about lithium cells but I'd like being really sure about single CR123 configuration safety first.

I heard about a few other cell brands failure but is there any case in candlepowerforums history where a single top quality CR123 like Surefire or Panasonic vented or exploded using a single CR123 flashlight?
If that ever happened in all time, I think I can really relax a bit more.

Beside that I'd still like to analyze some worries I thought they could lead a single Surefire/Panasonic CR123 to vent.

Damage - If I drop a Surefire CR123 on concrete when changing battery, could it vent? Ever happened to someone?
Heat - If I forgot the flashlight on at high level, could it become so warm to explode?
Discharge - If I continue use the flashlight on low level even if the high level stopped working/dimming, will it discharge to much to vent?

About discharge, I see many manufactors advertise their input voltage range as 0.8 - 3v. This means they will drain the CR123 cell down to 0.8v? I know that would be bad for li-ion but CR123 can go as low without issues?

I'm sorry for the long post or silly questions but I hope you can help me having a better idea about lithium techonlogy and its safety.

Thank you

Try this, do a google, cpf only, at the top of every CPF page, and enter Safe CR123, and see what comes up. Need to read more than the gloom and doom threads re CR123's.

Bill

Consider LiFePO4 from K2. I'm getting some as soon as available from Surefire.

I read on most thread for safe CR123 but most question still don't have a definitive answer to my doubts.

In my research I was not able to find any report about a single Surefire/Panasonic/Duracell ever vented or exploded in any single battery flashlight.
I guess that is pretty reassuring, if anyone knows different please chime in.

I did not found any info about dropping a Surefire CR123 on concrete. I guess if the drop is not violent enought to deform or short should be ok.

I read on on a Panasonic pdf not to heat CR123 above 100 degrees. I still don't know what temperature can get a common cr123 flashlight at max level when left on.
I also don't know what happen when reach such heats, will simply stop working or release gas or vent with flames.
Don't have a sort of thermal protection like PCT build in that turns off power when heating too much?

About discharging, some threads said it is ok to discharge down to zero volts whil some not, on Panasonic pdf states CR123 voltage cutoff at 2v. I guess they don't have voltage circuit built in to control it so will it go dangeruos to zero if the flashlight don't have a cut off?

In a more concrete example let's take my quark cr123 with a voltage range of 0.9 - 4.2 what happens if I leave it on at max or I still go on using low level even if the high level becomes unavailable?

I am still not considering rechargable batteries, there are so many things I'd like to learn about primaries first amd I also heard about LifePo4 and IMR explosion in e-cigarette community, guess all knid of lithium batteries even by venting only gas can generate an explosion if sealed in airtight tubes like a waterproof flashlight. Even Panasonic suggest not to use lithium batteries in airtight containers but then makes batteries for Surefire from what I understand.

Not an expert, here's my opinions:

CR123's are safe to discharge to dead.

Rechargeables aren't guaranteed to explode from over-discharging, but the potential risk increases.

When it comes to protected lithium-ion, most people either trust the protection circuit or don't want to rely on electronics for safety.

For me I don't want a battery that requires extra effort and responsibility to maintain safety regulations. My life is complicated already.

dantes said:

I also heard about LifePo4 and IMR explosion in e-cigarette community

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Can you please post links of LiFePO4 explosions?

A lot of what I read on e-cigarette forums is either low quality or modified batteries.

I've contacted K2 and they don't have any reported failures with their batteries.

And btw, if I own a battery that does explode, I'd file a lawsuit and report to government consumer safety agencies and become their worse nightmare. I take my family's safety pretty seriously.

Here's a few threads about safe chemistry failure, seems like a couple of Lifepo4 batteries sent a e-smoker to the hospital but even if the guy is pretty sure he was using LifePo4 batteries, actually there are no pics or further confirmation.

http://www.e-cigarette-forum.com/fo...ussion-exploding-batteries-4.html#post5038291

http://www.e-cigarette-forum.com/fo...oding-mods-current-situation.html#post5146201

http://www.e-cigarette-forum.com/fo...ures-serious-battery-failure-imr-18650-a.html

I may register and ask update about it because it would be the only catastrophic failure of such safe chemistry I found.
Even Surefire seems like is selling K2 LifePo4 for stacked use and advertise them like there isn't any safety hazard even mixing old and new LifePo4 cells. http://www.surefire.com/faqs

I hope they are right and there isn't any safey risk, I'd like to use them with no worries like Ni-Mh but in many threads is often pointed out safe chemistry cells are only less likely to vent with flames then standard lithium but should be still used carefully like most li-ions.

I guess unprotected safe cells could still get "reverse charged" if mixed with an unmatched cell. If they really fail they should not vent with flames and only relase hot gas hopefully less violently then lithium/ li-ions. (IMR and LifePo4 have vents hole on top like any other li-ion so they are still able to vent, while safer Ni-Mh don't have any as don't need them) IMHO I'd like too see at least a protected safe chemistry cell for short circuit and overdischarge.

Most e-cigarette have vents holes thought to decrease pressure and avoid explosion while flashlights don't have any being air tight sealed. Even venting only hot gas at some times the pressure will build up and could be tailcaps/heads rockets or shatter glass flying around. If all manufacturers thinked about some sort of pop-out venting seal it their flashlight, in case of safe chemistry venting (assuming they really vent less violently then li-ions) that would probably be enough to warn/avoid any sort of dangeruos explosion.

I am wondering, if rechargeable safe chemistry lithium cells are really safe why big companies like Pansonic do not still sell them to the public? I guess request is very high, add a quality charger and they would sell like hot cakes. Its seems like only Chinese manufacturers are willing take the chance.

dantes said:

(IMR and LifePo4 have vents hole on top like any other li-ion so they are still able to vent, while safer Ni-Mh don't have any as don't need them)

Click to expand...

Uhm, since when NiMH's don't need (& don't have) vent holes?!
All high quality ones do (Eneloops, Sanyo non-LSD, Duracell's, etc), they might just be well-hidden under the paper/plastic ring that covers the top (this ring doesn't prevents gasses from leaving the cell, though).

Thanks for the links...

dantes said:

http://www.e-cigarette-forum.com/fo...ussion-exploding-batteries-4.html#post5038291

Click to expand...

Unconfirmed batteries. Hearsay.

dantes said:

http://www.e-cigarette-forum.com/fo...oding-mods-current-situation.html#post5146201

Click to expand...

* Update 8/21/2012
We now know that the user bought standard lithium cells, and they may even have been primary cells. The batteries were therefore unprotected Li-ion or regular non-rechargeable batteries, which he then charged and used. These were not Li-FePo4 cells.

Note however that Tenergy Li-FePo4 cells are reported as commonly counterfeited, so that you may think you have branded Li-FePo4 cells but they may not be the brand on the label, and they could even be unprotected Li-ion cells. Stacking two unprotected Li-ion cells in a sealed or semi-sealed metal tubemod is demonstrated to be high-risk.

I have the same concern as the OP however no one has actually answered the OP's question. Does anyone know??

"is there any case in candlepowerforums history where a single top quality CR123 like Surefire or Panasonic vented or exploded using a single CR123 flashlight?"

To my knowledge, no. There was a case where a CR123 exploded alone in a drawer, years ago, and that was sort of a mystery. There have been examples of multi cell CR123's exploding, or at least venting while in a flashlight.

Bill

Thanks Bill!