Reviving Gel Lead Acid Batteries

[geekygrilli]

Hi guys

I was wondering if there is anyway of reviving the lead acid batteries on my daughter's ev (see off road thread). I have heard things such as shorting them, or whacking a huge voltage across them - but i'm a bit worried about doing this.

They have sat for years, they still have some life in them when charged. They're 2 off 12v 36 Ah.

Any advice appreciated.

Christopher

[qdos]

Yes pretty much as you have said, I've done this and it does work.

A safe way to do it is by charging and discharging across another similar voltage rated battery. So charge up a battery, be it one of the batteries in question or another lead acid, and then connect that in parallel to one of the flat ones. Repeat the excercise many times randomly.

[social misfit]

i heard of a way of rejuvenating GEL batteries is to use a 40 volt power source with a 1200 microfarad capacitor in parallel and pulsed through the battery once every 2 mins for how long i don't know but will give it a go sometime. the pulse duration is just the time for the capacitor to discharge into the battery,disconnecting the power source at the same time.
probably works the same as a pulse charger but with higher voltage.

[JonSpence]

I think that you want to do a google on
lead acid battery desulfator
or
Battery Desulphator

There are many designs out there. I first read of these a number of years ago, but have not had a need for one.

There are many designs out there, or you can buy charges that have automatic desulphators built in.
ie
http://www.optimate-sp.com/

NOTE don't use one while the battery is connected to anything else.

[ChrisB]

I've tried many ways of recovering Gel LA's and generally never had much success.
The problem is once they dry out their toast , although I have heard of folks pulling the sealed tops off adding some water to them and getting some more life out of them ??

ChrisB