Lithium battery explosion, personal experiences.

[chimera15]

So, I've been fixing oqo double cap batteries for my personal use.  I've been working on batteries for a long time.  I was trained as an Airframe and powerplant mechanic and have a lot of basic knowledge about batteries and electronics so I've always felt pretty comfortable.  My father is an electrical engineer and taught me a lot about stuff.

Today I made a really stupid mistake.  I tried to replace the batteries on a half dead pack while they were charged.  I've never had problems with this before.  I punctured a lithium battery before and while there was gas it didn't catch on fire or explode.  Today was different.

The packs were double sided taped onto the bottom of the case, and I tried, with a plastic spatula to pry them up, which normally I don't have any problem with.  I've done this several times before successfully with no problems.  Today the pack covering apparently separated or somehow there was an internal short and the pack caught on fire and was kind of like a smoke firework.  

I was very lucky that it only lasted about 5-10 seconds and none of the other 3 individual packs in the battery caught on fire or exploded in series.  

It caused a lot of smoke and I think I was lucky it didn't catch anything else on fire.  I was quick getting it to the sink, but didn't dowse it in water cause I had read before that that will just make it worse cause it will short the other packs.

The next time I try this I'll definitely make sure the packs are drained and hope that's what the difference was in why this one blew up on me and the one before which didn't..

One thing I was wondering is if the smoke/gas is poisonous.  I couldn't find any reference to this on the web anywhere.  It's kind of a sickly sweet smelling smoke, unlike a normal electrical fire or something.

The good news is that the pcb was apparently unaffected and I was able to save the battery pack and the new set of batteries are running a system now.

[chimera15]

Don't suppose this is related to this?

Lithium batteries are srs bzns...not really the most 'home-hackable' of things.

No, I'm not trying the uber one.  I found replacement cells for double capacity batteries, it's a completely normal replacement.  I found that a completely refurbed double capacity battery pack will last about 6-7 hours which is enough for my purposes.

 From what I've tried with oqo's at least they are pretty hackable.  The oqo is different from most larger laptops though which is what might make them more compilable to having cells replaced and such.  They use flat soft lithium cells like in a cell phone or pda unlike most larger laptops.
 I've replaced probably at this point dozens of batteries on laptops and pdas and never had anything close to what happened to me today occur.


I was stupid on a couple accounts, mainly because I was too impatient, but just because I had experience before where nothing bad happened.  I should have used goo be gone or some kind of loosening agent on the double sided tape, and I should have discharged the battery first.   I know from experience now it's a real threat.  This was actually the first time I had tried to replace cells on a battery that still had a pretty decent charge and a 75% wear rate and was still taking a charge.

I do have testing equipment and a charger.  The cells I get from a company are ready to be installed and don't need precharging or anything.

Actually I do possibly owe you for saving my life and house Kishy, because of your warnings I was probably a bit extra careful and aware and calm when it happened.  I didn't throw it across my room or something. lol

From now on I'm doing it outside for sure if I do anymore.  This was actually the last one I had to redo, of the bad ones I bought off ebay, so won't need to risk my life or at least hand for a while. lol

[chimera15]

I hate NiCads, NIMH, Lithium - all of them.  At any point in time I have one I need to replace.  Just bought some Makita 9.6Vs and now my portable shampoo dustbuster thing is dying.

I used to replace them with cells I bought and soldered in but now I just pull the battery and throw in my hazardous waste box.

Hmmm......this story indicates I should put my hazardous waste box outside or something.  Or at least put tape on the contacts.

Yeah this incident definitely makes me think more seriously about them. It got super hot, and I was really lucky it didn't catch anything else on fire.  The paint on the case the battery was laying on bubbled it was so hot.

It was probably only because I was working on it and the battery was open that all the heat and fire had somewhere to vent or the other packs would have gone for sure as well and it just would have been a really bad disaster.

 A friend of mines parents had a 9 volt battery make contact with something in a drawer and their entire house almost burned down as well. 9 volts can be really dangerous.

[chimera15]

I reread my other thread about a super capacity battery pack and noticed 8 inch floppy posted this video:

Couple interesting things about it that I noticed now that it happened to me.  

The explosion and fire don't seem to be likely to spread too easily. The fire that erupted made contact with several wood and flammable surfaces in my room and didn't ignite them.    It actually took multiple cells to fail in order to actually catch something on fire.  I was lucky that the more cells didn't cascade, but likely because the case was open it was able to vent the heat.

In that video you see the fire burns for a long time before it finally grows.  The laptop would have to be unattended in order for the fire to really spread.

The second thing I noticed is that they said they tried to puncture a battery and nothing happened which would be the case the first time I punctured one and there was no fire.  There's a missing ingredient I think in what actually causes one to explode.

It's possible that my trying to pry the battery cause some sort of short inside and didn't actually puncture the battery, because I don't think I actually did.  That then cause the package to vent and finally cause the fire...

[godly_music]

I like NiMH. Temperature resistant, no poisonous materials or reactions, doesn't explode. As unlikely as it is that a Lithium battery will ignite, it's not impossible. And that's not something I'm willing to deal with. Eneloops are awesome.

[typo]

lithium batteries tend to go bang if you look at them wrong. i also collect flashlights. i have had s surefire launch itself clear through a wall! so, asking for it is probably not advisable.