I call it a rumor because over the past two years, I've seen people say that they can gas, while others will say they are totally sealed and therefore will not emit gas. I never really had an opinion one way or the other.

Here's my story:

I had two "dead" Optima batteries that refused to charge. For the first one, my old, old charger (my Dad's from many years ago) wouldn't charge it. I was never real happy with this charger becuase it was so old and all of the cables were pretty flimsy. No big deal, but since it wouldn't charge the battery, I went out and got a brand new "fancy" battery charger. The fancy charger wouldn't charge the battery either, so I put it in recondition mode for 48 hours (it shuts off after 24 and the directions say that if it won't accept a charger after the first cycle, try the recondition again.)

Well, after the second recondition, it wouldn't accept a charge. Before giving up, I threw the old charger back on and all of the sudden, it would accept a charge. I charged it half way with the old charger and then switched to the new charger (the new charger won't charge at all if the battery is below a certain voltage). The new charger finished the charge and shut itself off. Just to make sure the battery wasn't throwing an error (the new charger has some diagnostics), I tried charging it again and within a minute or two, it told me that the battery was fully charged and shut off. Well that's great, I brought a dead battery back to life and all is well.

I followed the exact same procedure with the second dead Optima and got to the point where the battery was "fixed" and I was doing the final "double-check" charge like I described above. Well, I assumed that the charge would just shut off like it did for the first battery. I went off to do something else, and came back several hours later.

I notice that the charger was still on and thought that was rather odd. I get a little closer and I hear a sort of sizzle sound and see some smoke coming from the battery. I quickly disconnected the charger and stepped away from the battery to regroup.

I knew that I didn't want the battery in the basement overnight, but I really didn't want to touch it....well, I put on my safery goggles but decided that wasn't enough. I emptied a plastic storage bin to act as a shield while I moved the battery and put on my one of my hockey gloves to protect my hand and moved the battery outside.

The sizzle and smoke had stopped by this time, but once I got the battery outside I could still feel a fair amount of heat coming off of the battery.

Morals of the story:
1. I am an idiot
2. I know nothing about charging a battery
3. Optimas will gas if overcharged

Scott

It was an after-thought to go check on the battery before going upstairs for the evening.

I'm not sure if it would have exploded or not, but I'm very glad I remembered to check on it. I think I was better off with the old-fashioned battery charger because I didn't trust it at all...I would check on it all the time. The new charger made me feel like I could set it and forget it...lesson learned.

that would make sense. :-)

<ul><li><a href="http://www.amazon.com/exec/obidos/tg/detail/-/B00009RB0S/qid=1095215694/sr=8-4/ref=pd_ksr_4/104-7053525-5063910?v=glance&amp;s=hi&amp;n=507846">http://www.amazon.com/exec/obidos/tg/detail/-/B00009RB0S/qid=1095215694/sr=8-4/ref=pd_ksr

Or even better, give it to a fiend. ;-)

I had one that buldged out about an inch or two in every direction. No blow... scary but no blow. I use to work at an electric go kart track so I have had a lot of expereance with optimas. Amazing batt. we have had them fly out of a kart at 30 skid along the ground and we put it back in the kart and it was ready to go. Also like people said below most chargers should shut off.