Breathing life back into Lead Acid batteries

[Northern Irelander]

Not strictly cycling related but battery related

I have a dead cell in a car battery, apparently you can rejuvenate the cell by adding epsom salts. (250g Magnesium sulphate in 500ml of distilled/deionised water)

Has anyone done this for SLA's or LA's?

 

[flecc]

I've never tried it, but it's highly unlikely to be relevant to SLAs. Little or no access to cell content, paste electrolyte and sealed nature could give rise to many problems. No penetration of the paste or undesirable liquefying of it, pressure rise with semi-liquid discharge through venting for example.

Those battery revival techniques with various kinds that I've tried in the past have never been very successful, any gain very short lived.

Apparently reverse changing to de-sulphate a little used lead-acid battery that's died from lack of use is normally successful, but it's a highly dangerous procedure only for the very brave or very foolhardy. Not for me, I think the NHS has enough to do already.
.

 

[Northern Irelander]

Thanks Flecc, still haven't tried this (purely a time factor)

The battery had an easy life in a car that was hardly used. The dead cell appears to be clear, no black sulphides.

Will be giving this a go at some stage, will report back.

 

[banbury frank]

Battery repair

Hi Hear is a link for just that "Battery Chem" Battery Reconditioning and Rebuilding Supplies for Automotive Lead/Acid Batteries. At Home Battery Business Opportunity; Home Based Battery Business Opportunity


also look at battery desulfators

Hope this helps

Frank

 

[pictsidhe]

Double post

 

[pictsidhe]

A shorted cell is deader than a very dead thing, shorted is not fixable without disassembly. Sulphated cells have failed differently, they have an insoluble layer of sulphate that it may be possible to remove chemically. I have never heard of anyone trying epsom salts but did look into potential chemicals to try it with many years back, my dusty memory says some ammonium compound, acetate I think. I never tried it.

 

[Deleted member 4366]

You can buy proprietry battery rejuvenator pills that you put in the battery. I've tried them on tired batteries and they worked a bit. I guess they're made of something like this:
EDTA
I bought one of their deluxe desulphator kits and I'm presently trying it on a couple of large marine batteries. I'm not sure one would work on a dead cell because it relies on a pulse passing through the battery I'll report later if the desulphator works. I must admit that I'm a little sceptical.

 

[mike killay]

d8veh
Any luck with the de-sulphator?

Mike

 

[Deleted member 4366]

A shorted cell is deader than a very dead thing, shorted is not fixable without disassembly. Sulphated cells have failed differently, they have an insoluble layer of sulphate that it may be possible to remove chemically. I have never heard of anyone trying epsom salts but did look into potential chemicals to try it with many years back, my dusty memory says some ammonium compound, acetate I think. I never tried it.

Shorted cells are due to whiskers forming between the plates. sometimes they can be burnt off by putting a dead short across the battery.
Some people claim good results with a pulser. I built one and tried it on some knackered marine batteries, but I didn't notice any improvement, but it did bring a small SLA back to life a bit.
You can read all about battery desulphating and pulsers here, and IIRC there was a forum about it somewhere, that led to me trying it:
Car, storage and off grid battery pulser/ desulfator charger solutions
edit: sorry I didn't realise it was an old post.
My conclusion is that it's not worth it. If you have a shorted cell, it'd be worth trying the short circuit method, but I think you have to put a lot of trial and effort to be able to figure out methods to rejuvenate batteries. I guess that if you become an expert, you'll get better results.

 

[Biker44]

Not strictly cycling related but battery related I have a dead cell in a car battery, apparently you can rejuvenate the cell by adding epsom salts. (250g Magnesium sulphate in 500ml of distilled/deionised water) Has anyone done this for SLA's or LA's?

There were white tablets around in the 80s one could add to dying batteries and I was using them in a previous life. I'm pretty sure they worked somewhat.

But SLAs lead-acids these days are all sealed (that's what the S stands for!). My 2001 car battery is sealed but still going strong.

 

[flecc]

There were white tablets around in the 80s one could add to dying batteries and I was using them in a previous life. I'm pretty sure they worked somewhat.

This page linked to from the link d8veh gave is about this. Gets rid of sulphation but doen't do anything else to extend battery life.