Battery Exploded...what the heck?

[02fanatic]

My son's E30 is in storage ('86 325es with '89 325is engine), so I've been keeping his trunk mounted battery in my garage on a Griot's Garage battery minder...never had any issues. We've installed the battery to start the car on numerous occasions.

But, last time we put the battery in the trunk and tried to crank the car we heard a huge POP (like a car backfiring), then realized it was inside the trunk...the top of the battery had exploded throwing battery acid everywhere! (although there wasn't near the quantity of fluid I'd think there would have been)

Fortunately, the trunk lid was closed because I was standing next to the car.

I'm wondering what happened to the battery to cause this?

The battery minder is NOT suppose to overcharge

I used the battery to start my Jeep a few weeks ago and it worked fine

I'm wondering if after keeping the battery at full charge for a long time period, that the electrolyte level/water inside the battery evaporated to a low enough level that a spark between the plates cause the hydrogen to ignite?

Those are my thoughts.....anyone have this happen before, or know that could have caused this?

Thanks,

John

[spdracrm3]

yes to everything you said ,you still need to maintain electrolyte level on any charger system as offgassing is part of the charging process (read the charger instruction manual). so you made a little hydrogen bomb there ,gonna be a messy clean-up

[TobyB]

no, not between the plates, probably at the terminals...

The battery minder can't cook it, but it CAN produce some
hydrogen, and you must have squeezed out enough to ignite.

Bummer. I've done that. It's messy.

t

[02fanatic]

Thanks for the input guys.....moral of the story is to "make sure there's distilled water in the battery" where you can add water to the cells. AGM battery not applicable.

[UNHCLL]

I believe baking soda and distilled water are your new best friends to clean up the acid before it ruins the metal/paint. Sorry to hear about the mess John.

-Chris