Is It OK To Fill A Dry Battery With DI Water Only?


  #1  
Old 06-17-19, 06:40 AM
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Is It OK To Fill A Dry Battery With DI Water Only?

My C240 has sat unused for the better part of a year, I found the battery was bone dry of any acid. There's nothing wrong with the car it's just rarely driven now. The bat. was getting discharged/or unable to hold a charge. Reason, popped the caps and found it had zilch bat. acid. Not even a drip, in any of the cells. Refilled with DI water and all cells test about 2ish volts. I don't want to give up on it yet. It's an AGM type about 3 years.

Question is I know we can refill with DI water when acid is running low but can it be filled with no acid but DI water only?
If I have to buy acid how much is needed to fill a 12v Group Size H8, 900 CCA battery?
 
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Old 06-17-19, 07:19 AM
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While I'n no expert on battery's , I've own several AGM battery's and not one had removeable caps, or had water in it.
Just a tiny vent on top.
https://lateral-g.net/agm-battery-maintenance-care/
 
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Old 06-17-19, 08:06 AM
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The acid doesn't evaporate..... it's the water in the acid that you lose.
With the battery being dry for so long..... it may not come back to full capacity.
 
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Old 06-17-19, 08:53 AM
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OK. I added DI water and it's slow charging. Will see if it's bubbling in 12 hours
 
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Old 06-18-19, 03:24 PM
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Nothing happened, batt. is toast. Thanx for your ideas guys.
 
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Old 06-18-19, 03:48 PM
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The plates became sulfated and that's equivalent to a short across the plates.
 
 

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