Recovery for a vehicle's dead battery!

  spuds 11:05 16 Sep 2015

Not a computer question, but one about vehicle battery technology.

I have a number of 'dead' vehicle batteries, and under a load test, all are showing signs of dying or not holding a charge under load.

As a forum member any ideas or suggestions on how to perhaps rejuvenate a 12/24 volt vehicle battery. And especially so, if they did find a successful method. I would point out, that this will be for an experimental process more than anything, and where needed old batteries have been replaced for new.

Looked on Google and YouTube, and a number of suggestions are available, but self recommendation is required, on a possible tried method, by a forum member's input!.

  Gordon Freeman 12:03 16 Sep 2015

I don't think this is possible. Over time these types of batteries become unserviceable, the plates collapse etc, and they will no longer charge correctly, or won't hold their charge at all. Best to avoid any experimentation as the acid is obviously dangerous, so just dispose of them sensibly.

  LastChip 13:19 16 Sep 2015

If you can find an answer to this, you'll become a rich man. People have been trying for years to do this and no one to my knowledge, has ever come up with a successful solution.

  spuds 14:07 16 Sep 2015

Appreciate the responses guys.

One of the experiments we intend to try, is using an 'intelligent charger', and see what happens. Not saying anything will work, but never say never, its only a curiosity thing.

One particular 'dud' battery was put on a Crypton Pro charger for about 12 hours, dividing between Boost and Normal charge, and it held the charge for a number of days, including starting a 1.8 engine. The vehicle alternator seemed to keep the battery 'topped-up', but on leaving idle for a couple of days, the battery showed 11/12 volts, but collapsed on load test.

The vehicle batteries we buy are usually 3/5 warranty, and all, except one previous purchase lasted well above the warranty periods, so no complaints there. Strange though, that particular battery was replaced, and the replacement failed on connection. Fair dues to the supplier, money refunded without quibble, and a more well known brand given at no extra charge. That particular battery is still going strong after 8 years, with occasional use!.

  morddwyd 19:41 16 Sep 2015

Haven't seen them for a while, but it used to be possible to buy chemicals to rejuvenate batteries for a few months or more (my best result was a year!). Used to use them on my bike.

They work by de-sulphating the battery. Sulphate builds up on the plates during the charge/discharge cycle.

The product I used used to come in a pack of twelve "tablets".

Found this on Google

click here

  Govan1x 21:07 16 Sep 2015

They have a scrap value now but do not know how many you would need to make it pay.

You used to be able to buy diluted acid in a bottle from garages for batteries it would probably have had a name but not one that I can remember. Take it that probably stopped a long time ago.

  bumpkin 23:03 16 Sep 2015

Why you want to bugger about with old batteries for I don't know but from my experience when younger and skint I tried all of the so called rejuvenating methods and none where any good for more than a very short time if at all, don't waste your time and money.

  spuds 00:13 17 Sep 2015


Used vehicle batteries went down in price, and scrap value over recent months have since increased. The motor factor we deal with, will give £3.00 or more for a dud vehicle battery of any make or kind for a new replacement. The local council recycling depot, will take batteries (any kind) for free.


It isn't a case of "buggering" about (as you suggest), but as I have already clearly stated, its more for an experiment. We already have some equipment for commercial charging and checking, so there will be no further expenses to apply to this trial project. but it all might be entertaining in perhaps finding out a few facts.


I also recall how the markets were once awash with various aids, usually in the form of tablets or solutions, there are still some about, but in very limited quantities. We already have a commercial 'intelligent' charger for an whole range of commercial battery types, which goes through a number of procedures, and we will put that to the test. What I have found, looking on the internet, is devices like this, which seems to have good reviews. Amazon have a facility for contacting previous buyers of products, so I might try that for further advice, from some who is using that device click here

  Dragon_Heart 01:52 17 Sep 2015

" .... it used to be possible to buy chemicals to rejuvenate batteries for a few months or more ...... "

Most commercial batteries are now sealed so could not be used.

The 'intelligent' charger may work on some but not all batteries for a short time. Does this charger allow for several charge / discharge cycles ?

  spuds 09:19 17 Sep 2015


"The 'intelligent' charger may work on some but not all batteries for a short time. Does this charger allow for several charge / discharge cycles ?"

The one we have, covers a range of battery types (gel/lead etc). The sequence of events, is that it goes through a cycle of checks, then in some cases goes to a point of bringing the charge down to a point, then commences on recharging the battery to full capacity (if possible!). Basically, you connect the device, switch it on to a mains supply, then watch a series of 'progress' leds doing their work. When the device as decided its done any possible tasks, it then switches off to a trickle charge, just to maintain checks or future requirements, hence I suppose, that is where the 'intelligence' comes in!.

I would suspect that it follows the same principle of the device in the link i provide, but possibly goes that step further, by recharging the battery, where the other device doesn't have a recharge facility.

All good fun really!.

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