Need to uncork battery when charging?

[porcupine73]

Hello, is it necessary to uncork maintenance type batteries when charging? I always figure why, when the alternator charges the thing and you don't uncork it then, but my dad always said to uncork it when charging. Anyway today we were charging one and after a while it started bubbling around the corks which kind of surprised me. Any ideas?

 

[mechtech2]

Batteries are vented. If you were bubbling out the filler caps, you were over filled or over charging.

 

[Eddie]

Charging produces hydrogen gas. If a battery cap vent is plug the cell could explode and spray acid. In addition; by leaving caps off the hydrogen gas is realeased solwly and does not get to a high concentration that can explode. I leave caps on and keep any sparks, fire, cigeretts away while charging.

 

[porcupine73]

Thanks for the info guys. I'll bet this battery is overfilled. It took the charge like a banshee and started bubbling after just a couple hours.

I had just charged a different new battery overnight with the same charger and no bubbly. I always use the charger's lowest setting (2 amps).

 

[JavaMan]

Maybe a little off subject, but, I'll take a chance. While using jumper cables, I once had a battery explode right in my face and consider myself very lucky. I was practically deaf for about an hour, but, there were no permanent injuries. I would go with what’s safe.

 

[porcupine73]

Wow JavaMan that doesn't sound good. I always try to remember to wear at least chemical goggles and sometimes a face shield and always look away when hooking the last cable to the battery after seeing one blow up on some tv show. Hydrogen and oxygen recombining releases a lot 'o energy.

One time I was jumping another car and somehow I got the cables reversed and dude that was not good but fortunately no damage.

 

[JavaMan]

Well, I am not an expert on the matter, (don't take my advice read up on it yourself)if I need to jump start a car I ground to a metal part on my car and connect the positive jumper to the positive terminal on my battery. I do the same on the jumping car. If this is incorrect or if anyone knows a better method, please advise. The main thing I learned after this is a battery is pretty cheap.

 

[porcupine73]

I think the idea in jump starting is the final connection should be the ground connected to a metal point on the body and not the battery terminal itself as there will be at least some sparking when that connection is made and you don't want it sparking near the battery where the hydrogen might be.

 

[mechtech2]

In the OLD days, you would connect the positive cable to each car, then simply drive against it so the bumpers provided the ground.
[when jump starting]

 

[SHOZ]

As stated if it's bubbling out the vents it's too full. Someone has probably been over filing it. This cause Seth gravity of the acid to drop. This causes more gassing when charging.

Sounds like the battery is junk unless you can get some concentrated sulfuric acid acid and a hydrometer to equalize the electrolyte.

To be sure get a hydrometer and check the electrolyte strength. Otherwise pop $60 for a new battery and never over fill. Seldom do any batteries today need much water addition. When they do it is frequently the outside cells and this is caused by more exposure to engine bay heat accelerating evaporation of the water in the electrolyte.

 

[kgb007stb]

Watch out for those jump starts, I always connect the positives on both batteries first, then I am left with the negatives (this ensures I cannot reverse the connection). Then I connect the negative on the dead car to the ground far away from the battery just in case, and always connect the ground as far away from the battery on the live car. These things do like to spark and I do not want any blow ups in my face. What ever happened to the old days when my uncles were jumpstarting diesel trucks with plain electrical cables, no connectors at the ends and in best cases they came out with burns on their hands from the heat generated at the terminals. OUCH!

I believe that new batteries have calcium coating to prevent major gas bubbling during charging. If yours was not calcium coated, then it will give off gas during charging. Since this happened right after charging, the battery could have been given too much current and it tried to get rid of excess energy by converting electrolyte to H2 and O2 gases.

 

[Rickey]

quote:

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Originally posted by mechtech2:
In the OLD days, you would connect the positive cable to each car, then simply drive against it so the bumpers provided the ground.
[when jump starting]

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I have jumped 'em off by toutching bumpers (metal to metal) and using jack handles to connect the positives in an emergency. I don't recommend this however.