battery refill

[yadada]

So I checked my battery, way low on fluid level. I thought to my self, "I've got some acid left over, I'll put that it." So I did. Then I found the instructions in the bottom of the box. It basically says "Never refill with acid." What will happen if I run it that way? Boom?

I am going to use a large syringe and the tube from the acid bottle to suck out and refill with distilled water, then test and adjust with one of those litttle battery tester things....a hydrometer?....unitl it was back to the correct level of acidity, or whatever the little tester measures.

[Jerry]

The Lead Acid battery is made up of plates, lead, and lead oxide (various other elements are used to change density, hardness, porosity, etc.) with a 35% sulfuric acid and 65% water solution.

This quote and other battery info is from:
http://www.batterystuff.com/tutorial_battery.html

If you refill with acid you get a much higher concentration than the 35 - 65 mix. Your battery won't work as well; more acid does not mean more chemical activity resulting in more electrical output. In fact, the sulfur in the sulfuric acid get absorbed on the plates during discharge and returned to the electrolyte during recharging. A higher concentration of sulfer will make recharging - returning the sulfur to the electrolyte - more difficult, and lead to an early battery death.

So, adding more acid will decrease the output of your battery and cause it to fail earlier than normal.

[prometheus578]

Oh, I suppose you could try to suck some acid out and add back the water, but you'll never get the mixture correct, though you'd be getting it back to where it's supposed to be, to a certain degree.
Afterwards... run it till it eventually dies.

[yadada]

Thanks guys. This will be an excuse to buy an AGM battery....no more operator error.

[TopCatGr58]

The old battery was wasted anyways!

Hey Randy,

IF your fluid level was fairly low for while, I think the plates were already oxidized and wouldn't contribute much once they get back in under the solution anyways! SO...yes, a good excuse for getting a new one, whatever style you choose!
T.C.

[HobbyMan]

Did you try to charge it after you added the acid? if you did not, just take out what you put in and refill with water. How old is your battery? If you are trying to make it last, put it on a high charge and beat it with a rubber mallet (gently) or drop it on the ground a few times to get the sulfur off the plates. Let it cool every once in a wile and take the caps off the cells while just charging. (I have blown a battery up before) I know a guy that puts his old batteries in a paint shaker. ( don't do that) Some times you will do anything to squeze life ouy of your batteries.
Note: use good judment if you decide to do this and get a new battery

[mn2346]

You could also totally replace the flids in the battery with correct mixture, that would also take some of the grud out...

[Crazcnuk]

Just run the battery totally dead, run a headlight or something, then empty and refill with distilled water.

Then recharge, overnight with a trickle charger.

When the battery is discharged, it is full of water, when it's charged it's a Sulfuric Acid solution.

[OpFlash]

Saved my ass

Just wanted to say thanks for this thread. My XJ was flashing a warning for the battery which signals a low battery fluid level. Anyway I was going to just refill it with some left over acid / electrolyte fluid that came with the battery. I happened to be looking through the forums and found this thread. Whew! today I filled to the proper levels with distilled water. warning lights went away and I saved my battery. Thanks again I just recently purchased the darn thing.