Battery reconditioning methods!

Phantom

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Has anyone tried to recondition a 12v lead acid battery with any sucess? I've seen various methods used from draining and rinsing out to using epsom salts and a higher charge voltage, but do they really make much difference?
I plan to test out my mismatched leisure batteries in a few weeks time, but my car battery has been in poor health for the 5 months that I've owned it though it always starts fine so no great rush to replace it at present but likely will do before winter. Out of interest I emptied out the electrolyte into a clean bucket, and there was some black muck in there! So blasted the cells out with a hosepipe until clear. Then refilled with the same now clear electrolyte which had settled out leaving a thin black gritty layer in the bucket. Well just doing that alone followed by a low charge seemed to make an improvement to the battery, SOH was up from 23% to 37%, capacity from 310Ah to 390Ah, and resistance had dropped from 8.86ohm to 7.07%. Still not exactly great but just wondering if some further method could improve it as all cells seem fine? As said I expect that winter may well kill it off so will likely need replacing but there's no harm in experimenting a bit for now!
Any thoughts?
 

wildebus

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My new-to-me Motorhome came with a pair of good quality but knackered AGM batteries which both had just a fraction of the capacity left.
I rejuvenated one by a few charge/discharge cycles with the charger set at about the maximum it would go, so around 17V.
Charger was a Victron one and could see how many AHs were going in - and was a lot more then it should have taken, and was getting pretty warm.

Anyway, it seemed to get a good life back into it. I wouldn't use it as a Leisure Battery in a camper any more though as wouldn't want the uncertainty, but was interesting to do. If you do this, take precautions of course. Battery in a suitable box in case something splits and acid leaks, etc.
 

ricc

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depends if you enjoy playing arround and have the time, in my case I havnt got time to spend on speculative projects so would just look on fleabay to get a good price on a warrented new battery delivered tomorrow.
 

trevskoda

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It works IF and only IF the plates have some deposit at the bottom shorting them out, but if the plate/frames have collapsed or buckled then you are wasting your time, even then its only a short term fix if lucky, been there hade the T shirt many years ago when I was poor, ges forgot I still am. 😂
 

witzend

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It works IF and only IF the plates have some deposit at the bottom shorting them out, but if the plate/frames have collapsed or buckled then you are wasting your time, even then its only a short term fix if lucky,
Have given batterys a good hard shaking upside down then tipped them out repeated this after putting hose in to flush them out several times refilled with fresh acid re charged some have worked well for a while.
 

Bertilak

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As amusement rather than a recommendation, I remember there used to be a rejuvenation powder called 'Bataid'. An old timer told me this was salicylic acid, and that putting one ground up aspirin in each cell also worked...
I'd get a new battery, just to save the earache of it failing totally when in the wild.
 

trevskoda

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Just tape two of them little jump starter packs together as im told they are just the bogs dollocks. 😂
 

Okta

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Some battery chargers and devices have a reconditioning or de-sulphation programme. I believe they work by sending pulses of higher voltage into the battery to dislodge the sulphates from the plates. Not to be used on LiFePO4 batteries.
 

Robmac

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Some battery chargers and devices have a reconditioning or de-sulphation programme. I believe they work by sending pulses of higher voltage into the battery to dislodge the sulphates from the plates. Not to be used on LiFePO4 batteries.

My charger has a recondition phase which automatically kicks in if the charge isn't successful. I have revived a couple of batteries using this, but as Trev says, it's only a short term fix and if ever I have dubious batteries I replace them.
 

Phantom

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For £12 I bought a 7-stage + repair mode battery charger which arrived today so I hooked it up to my 24% SOH car battery. In first stage of normal charge mode desulphation lasted about 8 mins so I switched it to repair mode which appears to pulse charge the battery for 16 hours, so will leave it overnight to do it's thing. It'll be interesting to see what difference if any that makes?
I removed the battery from the car shortly after driving it and the battery analyser showed it to be 12.1v but only 24% SOC, and after just a few minutes charge it then read 92% SOC.
Maybe it would benefit from being discharged then a 7 stage charge? Just a bit of fun to see if it can be improved at all but will source a replacement as expect it to be needed before too long.
 
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wildebus

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it is typical for a knacked battery to have an apparant very fast recharge. And the owner usually thinks they have a great battery (look how quick it charged) and a great charger (look how fast it recharged the battery). Simple maths and physics will reveal it can't happen.

TBH, those SOC numbers and a desulphation process for 8 minutes is not encouraging. but interesting process to do non the less.
 

Phantom

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TBH, those SOC numbers and a desulphation process for 8 minutes is not encouraging. but interesting process to do non the less.
From what I can tell the charger in repair mode appears to be pulsing to 14.4v at about 1 amp so I am not expecting much if any difference at all from that process. I read that all wet lead acid batteries like a good long charge every so often but our car really only gets used for short runs of about 10 mins each. Even with the battery at just under 12v I'm surprised that it still spins the diesel motor over as normal, but I'm going to replace it anyway before it let's us down, but it has done very well to last over 10 years!
 

trevskoda

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From what I can tell the charger in repair mode appears to be pulsing to 14.4v at about 1 amp so I am not expecting much if any difference at all from that process. I read that all wet lead acid batteries like a good long charge every so often but our car really only gets used for short runs of about 10 mins each. Even with the battery at just under 12v I'm surprised that it still spins the diesel motor over as normal, but I'm going to replace it anyway before it let's us down, but it has done very well to last over 10 years!
The engine must be knackered driving such short runs, give it a few blasts down the m way every few weeks to clean the oil & internals, plus it will stop bore glassing.
 

wildebus

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The engine must be knackered driving such short runs, give it a few blasts down the m way every few weeks to clean the oil & internals, plus it will stop bore glassing.
I wonder how those super-low mileage motorhome mechanicals are when I see the adverts for vans with less than 1,000 miles a year. We had two cars in the household until a couple of years ago, one of which used to do maybe 800 miles a year - every year that car needed new brakes for the MOT from being sat around doing nothing in the damp scottish environment.

Ref starter battery, it really should be remembered that the alternator puts charge into a battery but is not a "battery charger" - to really look after a starter battery, it should have a multi-stage charger connected overnight once a month at least.
The only reason Starter Batteries last as well as they do with the charging they normally get is the technology has improved so much over the years - but use a charger and they can do even better (y)

10 years is great going mind. Treat the old girl to some new juice ;)
 
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