Newbie battery help: overcharged?

[Aguiltinan]

Hi everyone,
We just took our "new to us" 1991 sportsmobile (Dodge Ram) on a road trip to Canada and back (from northern California, SF Bay area).
It was a great trip, and the van ran flawlessly and camping it it was great...but I think I may have done something wrong related to the house battery and killed it....so thought I would post here to see if I can glean any useful info from you more knowledgeable folks.
The first time we camped at a site with a power hook up - I plugged it into to the shore power and left it plugged in during the night. We were running the refrigerator and a few lights - not really that much power needs for the type of camping we do. But sometime during the night I woke up to a very supherous smell and it seemed like the battery was hot. I went out and unplugged it, but seems like it was too late. From that point on the battery does not hold a charge for any amount of time. The refrigerator will run when the car is running, but shuts off shortly after the van is parked.
I had understood that there was some sort of regulator which would keep the battery from overcharging when plugged in - but either it's not there, or it's malfunctioning.
I'm planning on getting a new battery soon....but want to make sure I have enough info so that I don't kill another one.
Thanks for any assistance!
Best to all,
Anne

[BajaSportsmobile]

Unhook the battery and charge it with a battery charger and then have it tested - battery might be OK. I would suspect that your converter/charger may have failed - it needs to be tested also.

[vwteleman]

Anne,

Two things:

• 1. You may not have a smart, 3-stage charger that levels off to a float charge (the "regulator" you speak of).
  2. Have you checked the fluid level in the battery? Sulphur smell can mean overcharging, which boils off the water. Refill with distilled water, then do as BajaSportsmobile mentioned.

Good luck.
Brent

[daveb]

Battery off gassing = possible overcharging but more likely off gassing indicates a bad battery. There is no overcharge protection on a normal SMB build; even a smart 3 stage charger can overcharge a battery in the right circumstances. Perhaps you are thinking of the battery separator. As a rule it does supply protection from discharge but not overcharge. Gauges usually will tell you about overcharging; look at the voltage gauge on the dash and make sure it's not in the red (below 15v) Then check the voltage on shore power...it also should not be above 15v. A bad battery will often heat up during driving or shore charging. They can get fairly hot making it easy to find the bad one. Although I have never seen a battery explode, it can happen when off gassing like that. Open and sealed wet cell batteries also spew an acid/water mix that eats metal.

There are several post in the FAQ's in this section covering this as well.

Good luck.

Dave.