BhargavThakkar : Car battery Repairing

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If the one cell is "burnt out" the battery is kaput. You will only be using the five cells, which is generally not enough to start a car. Other problems also exist if you choose to use the failed battery...but won't get into that.

I suspect the cell in question is "shorted", meaning the paste on the plates has flaked off and come into contact with an adjacent plate of opposite polarity. No amount of "pulsing" or flooding with electrolyte etc will fix this problem.

Practical fix is to remove the electrolyte from battery. Flushing battery without thumping it on the ground will remove most dislodged paste. I would only bother doing this on "new" batteries that deserve some type of resurrection and is not covered by failure under warranty.

Refill with new electrolyte only when you are satisfied that you may have removed all loose paste. When mounting battery back into car, I would recommend using a thick rubber mat as a base to absorb vibrations, as it seems you may have a dodgy battery to begin with that will be prone to future failure.

Cheers