Renovating batteries.

[fizzy]

Maybe to unspoil things...

I'd say the one holding 12v+ stands a chance of being alright. The 6v one is probably fubbered.

I've had approximately a 50% success rate with 'dead' batteries. I look at it as being worth the hour of faffing at that rate.

The most surprising result was a heavily sulphated one that I used for about a year in a car after a seriously risky procedure - DO NOT try this at home

12v battery, connected backwards to a 24v charger for a few minutes, then charged as normal.

Two others I've tried that on had a moderately enthusiastic failure response - outside about 20 metres was the 'safe zone'

I have also had success reverse charging - I just used 12V backwards though not 24!
I think you can buy proper chargers now that use that process.

 

[Fazerruss]

I have two large 230 amp batteries that i need to try and recusitate.
After taking them off my truck as i thought they have no fluid in.

Would you lads try adding distilled water or try battery acid.

I am aware they might be past saving but at 250 quid a piece i would like to try.

250 quid each?!! That can't be right, I've never known vehicle batteries to be that expensive.
When you say truck are we talking HGV with 2 on a 24v circuit?

 

[GW8IZR]

You 3 have spoiled things now.

I am rather hoping one is duff and was dragging the other one down......

Realist based on experience I'm afraid

You havent mentioned the application but *if* you are charging these batteries in series on a vehicle to make one 24v battery - like a typical old HGV setup then even if just one battery partially recovers, and you fit one 'new' one - the life expectancy of the new one won't be improved. Keep a careful eye on both battery voltages in use as they should be very closely matched.

In addition make sure no one has tapped a 12v feed from one battery to run 12v accessories as that is a sure fire way to damage both batteries in short order.

As for connecting a 24v charger the wrong way round...... run away and hide!

 

[500e]

GW I think that is what pdg was alluding to in his 20 yard comment have had a battery explode not a good experience

 

[ukracer]

250 quid each?!! That can't be right, I've never known vehicle batteries to be that expensive.
When you say truck are we talking HGV with 2 on a 24v circuit?

 

[ukracer]

Realist based on experience I'm afraid

You havent mentioned the application but *if* you are charging these batteries in series on a vehicle to make one 24v battery - like a typical old HGV setup then even if just one battery partially recovers, and you fit one 'new' one - the life expectancy of the new one won't be improved. Keep a careful eye on both battery voltages in use as they should be very closely matched.

In addition make sure no one has tapped a 12v feed from one battery to run 12v accessories as that is a sure fire way to damage both batteries in short order.

As for connecting a 24v charger the wrong way round...... run away and hide!

They are in parallel in a 12 volt system.

 

[GW8IZR]

Are you saying these are two 24 V batteries connected in parallel?

 

[GW8IZR]

GW I think that is what pdg was alluding to in his 20 yard comment have had a battery explode not a good experience

Yes exactly in fact 20 yards is pushing your luck :-).

The worst one I had was someone had used red tape on the Earth lead on the car but I was jumpstarting, my fault I should’ve checked of course.

The top came off the battery and sprayed me with acid. No permanent damage very lucky

 

[ukracer]

Are you saying these are two 24 V batteries connected in parallel?

Sorry mate a typo connected with brain malfunction...corrected now. 12 volt batteries

 

[ukracer]

Update...both batteries are as dry as a bone. Should i try just ionised water or try and find sone sulfuric acid..?

 

[Seadog]

If they had fluid but have dried out then I would have thought de-ionised water. They will have discharged over time and absorbed the acid to a degree. Try a charge and then measure the pH or sg to determine whether you need a more or less acidic solution. At the end of the day, though, I think you're flogging a dead horse, but always worth a try.

 

[ukracer]

I cant find my old cheapo charger..... can i use the float charge on this charger.

https://uk.rs-online.com/mobile/p/b...GVXribpUq-4-d8JINrUaAsadEALw_wcB&gclsrc=aw.ds