Sealed Lead Acid Battery Repair – how to repair a sealed lead acid battery

In this video I try to show how to repair a sealed leac acid battery.

I got this battery from a friend, who used it in a portable Flash lighting unit
and he has unfortunately charged up this battery for too long, so it was overcharged and dry and did not accept any charge anymore..

This type was a 12 Volts 12 Amphour battery with 6 cells.

Normally these batteries only dry out after a while due to overcharging and the electrolyte´s water just evapourates and leaves only more concentrated sulfuric acid inside the cells which can eat the lead plates away.

If such a battery has only dried out, you just open up the top plate
which is just glued onto the main battery case and just remove the rubber filling cup lids and add again freash new destilled water to each cell and afterwards charge them up with a Bedini or Joule Thief type puls charger…

But in this case I just realized that 2 cells were damaged as there had already built up a bulge internally, that pushed the plastic cover up on one cell.

So this was probably done by overcharging. So this battery can not be revived this easily and it needs now to be opened up completely and see inside the defective cells, if these can be fixed somehow…Maybe remove some lead dust or powder which shorts one of the cells…

If I can find the time I will do this in the near future…
Hope this helps.
Regards, Stefan.

You may also like...