I suspected a spark ignited the gases and I looked to see if the cables were loose but none were. My charger has eyelets on the battery connector and mount to the side post battery cable bolts. Battery was still locked down with the clamp at base. Still could have arced somewhere but doubt it came from the charger connection.

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Baking soda mixed with water to help get any acid nuetralized,as quickly as possible. As mentioned the battery while charging does give off a gas, mainly hydrogen gas. Dirty posts tend to be the culprit for a spark, however as for the gas emitted from the battery,that is probably caused by either a low water situation in the battery itself or from a bad/shorted cell. When a cell is shorted, it's just as it sounds,two plates in that cell touch,creation a short in the cell. This short creates a lot of heat when charging basically boiling the electrolyte in the battery. Actually it's more like electrolysis, separating the components of the acid into hydrogen gas and sulpher deposits. These sulphur deposits are usually the root cause of a short,they can bridge across the plates completing a circuit. Batteries left discharged are more prone to this happening. Anyhow, hopefully the cover was down over the battery to minimize the spray,but chances are whatever carpet it got on will show holes or deteriation in short time. Plastic usually is not affected by acid, but leather is. Still, I would soak what I could with a mix of baking soda and water(or get an aerosol can of battery cleaner, it's usually the same thing just easier to spray in spots).

|UPDATED|8/31/2016 10:39:04 PM (AZT)|/UPDATED|


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StingrayJim
NCM Lifetime Member #1936

Stingray's '76���������������������������� StingrayJr's '78���������������������������Lil Red '94

(click each one to see a bigger version)

Thanks for your post. The terminals were clean when I removed the battery. I suspect an internal short. Unfortunately, I suppose, the lid was open and there was a large amount of vapor inside the car. Made me wonder what would happen if the door had been latched? The explosion seemed loud enough that makes me wonder if it would have blown out the fiberglass compartment? Guess I'll talk to my insurance company today as I suspect I'll be replacing a lot before this is over with.

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I suppose I'll go ahead and replace the battery today so I can get it out of the garage. Anyone want to recommend a safer battery?

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As for a "safer" battery, well probably an Optima, or some other AGM type battery as they are sealed, and the electrolyte within them is a paste instead of a liquid making it less likely to produce sufficient amounts of hydrogen and oxygen gasses making an explosion less likely.... however, they do come with a premium price...  but I've never seen one that blew up(18 years with a battery distributor but they are a bit more sensitive to being overcharged...... and yes, when a battery does blow up, its LOUD!   like 12 gauge shotgun loud, at least it can be, sometime they just "pop" like a paper bag.  Usually the force from the blast is focused upward, not so much outward, so, the compartment might have survived the blast.  

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StingrayJim
NCM Lifetime Member #1936

Stingray's '76���������������������������� StingrayJr's '78���������������������������Lil Red '94

(click each one to see a bigger version)

I always keep mind on a tender but my T tops are always off also in my garage.  Switched to an  Optima on my last battery buy.  I like the Optima so far, had it over a year now, maybe longer.  Red top Optima.

Unfortunately, Otima batteries are now not that good.  Ever since Johnson Controls bought them a few years ago and moved manufacturing to their Mexico plant.




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thats kinda true, optima was a small company in colorado i think??... but yeah since Johnson Controls bought them out, they have suffered in the quality... but, i think i would still take one of them over the Exide version(orbit??)  not really sure about other alternatives.  However, who knows/ they may make a comeback being made in USA??? Still, over the years we at the warehouse never saw any real advantage to the agm batteries for "casual" automotive purpose, now for track racing, off road, rock climbers and the such, yes they do fill the niche...  

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StingrayJim
NCM Lifetime Member #1936

Stingray's '76���������������������������� StingrayJr's '78���������������������������Lil Red '94

(click each one to see a bigger version)

Back in August, I replaced the 6 year old Optima Red Top in the vette. New Optima Red Top was manuf. by Johnson Controls. Did the same with the 6 year old Optima Red Top in my Tundra last week. IMHO, you can find them less expensive, but do not purchase on-line.

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There are several other brands of AGM batteries besides Optima, Lifeline being one of the better one.

Also if the battery tender wasn't one that is microprocessor controlled, it might have boiled the battery dry.


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1973 L-82 4 spd

Did you have a refillable battery or sealed? I believe the original type battery in 1970 had a vent to which a hose was connected that went through the floor to vent outside. This allowed for generated hydrogen gas to vent outside rather than in the battery compartment. My opinion is to not use a battery tender for a 1970. The only thing running is a working clock. I start mine once or twice a month and that seems to be adequate to keep enough charge on the battery.The last battery I replaced had 14 years on it.