so my battery EXPLODED today...

I have a small diameter crank pulley and with electric fan, water pump, and fuel pump I wasn't getting 12 volts at idle and that was without any lights. So I changed my 60 amp alternator with external regulator for a Powermaster 140 amp 1-wire alternator. I had the battery charging for several hours because I hadn't been charged for a long time. I then started the car and it cranked a little slow but it started. No choke so I ran it at high idle for a half a minute or so until it would idle by itself. I got out and put my volt meter on the positive terminal of the starter relay where the alternator charge wire is hooked up. I got 12.3 volts at idle and 14.3 - 14.4 at around 2000 RPM and the voltage didn't go any higher with more RPM. Then after running for 3-4 minutes the car stalled. I thought it was out of gas but I gave it a couple of pumps and tried to start it again. This time it cranked even slower and before the engine fired the battery exploded. So I'm wondering if my new alternator has a bad diode giving the battery some AC voltage or something. I just think it's really weird that it happened when the engine wasn't even running. I think my next step is to have the alternator tested. What are your thoughts?

 

Sounds logical. Glad you didn't get hurt.

 

Theres no interior in the car and the battery is in the trunk. My ears were ringing for almost an hour after the explosion. Other than that yes, extremely lucky. My garage door was open and one of the cell caps flew straight up, hit the garage door going through the insulation and putting a nice outward dent in the door. There were plastic battery pieces all over. My aluminum battery box is all bent up (the lid wasn't on), and my trunk was filled with acid which I had to clean up. Very glad I didn't get hurt though.

 

Part of the problem, if not THE problem, is that there is no air circulation in there. A spark could have been the cause.

 

No air circulation where? The battery box top has never been on it and there is no trunk lid on the car. Not sure I'm following you...

 

Being in the trunk in the battery box it's like a box in a box. No lid and no box top is open, at the top. It seems that unless the vehicle is traveling down the road there is no fresh air "movement" inside the trunk area. From what I read you say, you had the battery charging. Batteries create a gas while charging and usually have surface gases just sitting still. I'm sure you know this.

 

I just figured since everything had been open the gasses wouldn't concentrate.

 

After having one blow up next to me, me being stupid, and seeing another blow up in a bus drivers face, I now have a habit of blowing air across the battery each and every time I am servicing one. I wear any type of glasses and do not stand closer than arms length to it. Know where the closest water is. It will melt the eye balls and burn the nostril membranes . I can only imagine how bad that would hurt.
I have noticed on vehicles that have a box type holder or cover that the battery sits on a raised platform. The platform then has at least one hole. I am thinking the hole is to allow the gasses that concentrate to fall out. Theoretically speeking, I think the gasses are heavy. My wife's Trailblazer has a tube connected to the bottom of the battery tray. That tube then runs and connects to the fan shroud. The battery does have a cover.

Anyway.. It could be a charging issue as you though could be a cause.. I'm gonna lean towards the gasses. Let us know what you find.

 

GM uses a lot of remote batteries. They are vented externally to reduce the chance of a spark at the terminal igniting the fumes.

I'm inclined to agree with bluegene. I think it is likely that a spark at a battery post ignited the fumes, which could be building up rapidly if the battery were overcharging.

 

Batt. may have been very low on electrolyte as well. Then it contains a lot of hydrogen in the case. Couple that with recently charged and you got a bomb. One tiny spark and its game over.

 

If the fumes are heavier than air they could concentrate in a box with an open top .... just like an open chest freezer at the grocery store. The cold air just puddles in the freezer.

Glad you didn't get hurt .... I have blown up three batteries over the years, and was standing somewhat close to the first one. Was jump-starting that one. The other two exploded while starting the cars. Never ceases to really get your attention ....

 

this brings up a question about battery boxes.
nhra requires a sealed battery box with a vent hose to the outside of the car. all the nhra legal boxes ive seen have this vent hose at the top of the box. now wouldnt it be better if it was at the bottom of the box?
i imagine that if john was using a vented battery box with the vent at the bottom that would have allowed the gases to effectively drain out of the box. does anybody know the reason why the battery boxs have the vent towards the top?

 

Maybe so fluids will not leak to the strip or track if it did leak?

 

If the fumes are, in fact, heavier than ambient air, a vent at the bottom of a sealed box probably would make more sense. But that would hinge on the density of the fumes.

 

I don't have a battery box in my trunk I just have it secured. I figure its better ventilation and a lot cheaper then NHRA approved box. But the vent hose on top of a battery box is to vent the hydrogen gas produced when the battery is fully charged. Hydrogen gas is like 10 times lighter then air so it needs to be on top. Overcharging can bring the acid to a boil making lots of hydrogen.