Add Water to Battery or Acid?

[AdmiralYoda]

I have a used but good 12V Group 35 battery that was stuffed into my shed and forgotten about a couple of years ago. It measured 9.2V so I decided to see if I could bring it back to life. It immediately took a charge and I've had it on a trickle charge for about a week an it measures ~12.6V without the charger on it.

It is a little low on water/acid. Normally I just add some water and call it a day but I don't mind doing things right. Would it be worth it to add some "Battery Electrolytes" which is essentially just battery acid? Or just add some water and call it a day?

Thanks!

 

[Chris142]

Water. Acid does not evaporate. Its been my luck that a battery such as yours will completly fail very soon

 

[walterjay]

I would just use distilled water.

 

[AdmiralYoda]

@Chris142 This battery came out of my wife's 2016 Mazda CX-5 as it was acting a little weak. I'm not trying to restore it to brand new condition for use in another vehicle. It will just be a charged up spare for jump-starts, 12V gadgets, etc.

If it has enough life in it for those functions I'll keep it around.

 

[bullwinkle]

A pulse charger like a Battery Minder will do wonders for a sulphated battery that's been sitting, unless the grids are disintegrating, in which case it'll get a shorted cell anyway.

 

[oil pan 4]

Add some water and hook it up to a DC stick welder power supply for a few minutes.

 

[Auto tech]

I have a used but good 12V Group 35 battery that was stuffed into my shed and forgotten about a couple of years ago. It measured 9.2V so I decided to see if I could bring it back to life. It immediately took a charge and I've had it on a trickle charge for about a week an it measures ~12.6V without the charger on it.

It is a little low on water/acid. Normally I just add some water and call it a day but I don't mind doing things right. Would it be worth it to add some "Battery Electrolytes" which is essentially just battery acid? Or just add some water and call it a day?

Thanks!

Distilled water

 

[Donald]

Distilled water

+1 - always distilled water.

Some motorcycle batteries are shipped dry. You add battery acid & water (supplied with the battery when you buy it). Cannot say they still still ship them that way, but they did.

 

[Auto tech]

+1 - always distilled water.

Some motorcycle batteries are shipped dry. You add battery acid & water (supplied with the battery when you buy it). Cannot say they still still ship them that way, but they did.

They still ship dry certain brands

 

[meep]

Water. Not acid. Tried a number of things years ago. Acid will most likely shorten its life.

 

[ecotourist]

Unless the local yokels tipped your car onto its side as a Halloween trick and battery acid ran into the fender. Then the problem isn't just evaporation and you need to add acid too.

And get a new car when your wife doesn't want to be seen driving a car with an acid etched fender.

 

[Speedbird001]

+1 on distilled water only (The water evaporated, the acid did not)

FWIW a few years ago I pulled 6 pairs of large batteries that were newish, but left to bake in the desert for 2-3 years. (Literally, baking in a motorpool in Africa where it was 90-120 every day). Cleaned up, we could only get bottled water, so that is what we used. Drove them around charging a few hours (They were mounted in a military trailer)... IIRC 8 of 10 came back to life just fine (2 had leaks, 2 never got their voltage back). I think the driving around / vibration helped.

 

[f355spider]

+1 - always distilled water.

Some motorcycle batteries are shipped dry. You add battery acid & water (supplied with the battery when you buy it). Cannot say they still still ship them that way, but they did.

I remember those days...I think they only allow shipping AGM and lithium motorcycle batteries now.