lithium battery safety

[brianch]

I carry flashlights with me everywhere, each with their own lithium batteries in side. The safety of the batteries inside these lights have never concerned me until recently. One of my friends had her laptop battery explode on her. The battery was of course an aftermarket battery. The level of destruction caused by that battery was a bit scary. So I am here with a few questions to the battery experts. I own all sorts of batteries. From cheap DX batteries to the AW's and name-brand primarys.

What exactly causes the batteries to explode? Do the batteries actually explode, or do they release gas rapidly? And when they do explode what generally happens to the flashlight holding it? Are primary cells less likely to explode then rechargables? Will having more batteries in series increase the likelihood of an accident?

I am sure some of these questions have been answered all across this forum but I have not found a single thread with all the answers. I am very paranoid with my flashlight now, but I don't know if I should be. The more I research about this, the more I feel like not carrying my flashlight. I need some help oo:

 

[moldyoldy]

I do not believe there is only one thread that lists all of the information that you are looking for. Check out the stickie at the top of the forum on "Smoke and Fire, Hot Cells and close Calls - the Dangerous side of batteries" and read thru some of the threads. In particular to your question, check out this thread:

http://www.candlepowerforums.com/vb/showthread.php?t=235164

As for the laptop self-destructing - yes, laptop batteries do spontaneously combuste by themselves, even the brand name batteries can do that, albeit not often. The reason usually provided is often that impurities crept in to the manufacturing process resulting in an incipient failure at some undetermined later time. Although many laptop users become complacent because nothing has happened to them or their friends, all that is needed is to increase the survey "population" to hundreds or thousands of laptops over a few years such as at a large company. Then one becomes a lot more careful about the care and feeding of that large laptop battery.

However to provide an abbreviated answer to your usage question: Single-cell flashlights with primary CR123 or protected RCR123 cells are generally safe. Multiple cell lights significantly increase the chance of problems even with CR123 cells because a Lithium-something cell may be forced into voltage reversal during discharge - very bad. If you use RCR123 cells, prefer to charge often and do not wait until the protection circuit cuts off the current.

Review the stickies or search CPF for reliable chargers if you use RCR123 cells. There are long threads on the subject. All of this should simply reinforce the idea that the flashaholic needs to purchase quality batteries and chargers admittedly at a higher price.

Moldyoldy

 

[brianch]

Thanks for the reply. I have always known the basics of battery safety but have never looked into it in detail. I have searched on CPF and have not found anything really detailed either then 1. use brand name 2. dont overcharge 3. don't overdischarge. I found this link on the internet that gave some good points. http://www.flashlightreviews.com/features/123burst.htm

After seeing what happened to the laptop and the table under it, I have definitely been more aware of the dangers of carrying lower quality batteries with me. I have just ordered 50 primary panasonic 123a's and plan to use those in lights that I carry on my body. My paranoia is effecting my flashaholicism.

 

[Mr Happy]

Both lithium primary and lithium secondary (rechargeable) cells can have hot and flaming events.

With primary cells (CR123A) events are typically triggered by mixing new and old cells in the same light, or using low quality cells from China, or using excessively old cells. There are not really any reports of problems where people used fresh high quality CR123A cells with a brand like Surefire, Duracell or Panasonic.

Lithium ion rechargeable cylindrical cells arguably have less of a problem. As long as you don't over discharge them, or overcharge them, or apply high charge rates to over discharged cells, there is unlikely to be an event. Exploding laptops are typically caused by faulty battery packs, or low quality aftermarket batteries.

 

[Norm]

Battery University.
Norm