Can battery be recovered?

TuppenceHapenny

My car's been off the road for some time, parked in a garage. I've been keeping the battery alive by recharging it periodically. It's been a while since it was last recharged so I put the charger on for about 8 hours yesterday and another 8 today. However, although the electrics are coming on OK, the starter motor isn't starting the car, behaving as if the battery is out of charge.

Have I left it too long since last recharging and the battery is beyond recovery or is there any chance of getting it working again? Is there any point in putting the charger on for more time in the hope the battery will gradually come back?

Thanks for any help.

debtdebt

Battery might be brought back but you'll need a decent charger / reconditioner. This might cost more than the battery itself so maybe just buy a new battery?

forgotmyname

Pointless messing, you will waste more money trying to fix it rather than just fitting a budget battery.

Charge for longer who knows, 1amp (max) charger then 8 hours is nowhere near enough, 3 or 4 days for a larger battery would be more like it.

Goudy

The battery would be suffering from sulfation if it's not kept charged properly.

Sulfur from the lead acid forms crystals and they are attracted to the negative plates, stick to them and reduce the plates ability to react with the acid.

There is soft and hard sulfation, soft you can usually recover but it requires a steady 200mA charge for around 24 hours at 50C or so if you catch it early enough.

Hard sulfation can't be recovered.

For all the messing and not knowing if it'll be reliable after, best fit a new battery.
If you plan on continuing to store it, fit a trickle charge to it and try not to store it in too cold a place.

AdrianC

When you say "recharging it periodically", how flat had you been letting it get?

Had you left it attached?
What sort of age of vehicle?

caprikid1

Buy a CTEK Battery Charger (CTEK MXS05) or similar, I have brought many batteries back to life with these.


It could be that is dead and nothing will save it, but if you buy the above charger and use it in trickle charge mode you won't kill the next battery.


I have old cars that do minimal miles and just accept that a battery every few years is what is going to happen. The worst was a Caterham that used a tiny motorcycle size battery to start a 1.8Ltr engine, it ate those for a past time.

neilmcl

+1, for CTEK chargers.

Norman_Castle

Is there any point in putting the charger on for more time in the hope the battery will gradually come back?

I would....

TuppenceHapenny

Thanks for all replies.

In answer to questions above:
- The charger I've been using is a 'challenge' 6A Automatic Battery Charger. It's been effective up to now.
- The battery has been stored in the car but disconnected, so in winter it gets pretty cold.
- The car is more than 20 years old but the battery is much younger - more like 10 years old.
- I've often been leaving it few months between re-charging, to the point where the battery will no longer start the car but the electrics still work perfectly well. Then after re-charging for a good few hours the car will start again (though I don't know how reliably).

AdrianC

TuppenceHapenny wrote: »

- The charger I've been using is a 'challenge' 6A Automatic Battery Charger. It's been effective up to now.

Something like this?
https://www.amazon.co.uk/Challenge-Volt-Battery-Charger-7404355/dp/B004WL7T2U

Not a smart charger, so it may cook a battery. Putting lights on to show the battery voltage is lovely, but does it cut off charging when fully charged?

- The battery has been stored in the car but disconnected, so in winter it gets pretty cold.

OK, so at least it's not being flattened by things consuming power while the car's not in use.

- The car is more than 20 years old

Not so computer-heavy as modern stuff, but still likely to have clock/radio memory, possibly alarm and remote locking, though if it's disconnected, they're not relevant.

but the battery is much younger - more like 10 years old.

Aha. It's almost certainly died a death, then, but you must have been doing something right to make it last this long.

- I've often been leaving it few months between re-charging, to the point where the battery will no longer start the car but the electrics still work perfectly well. Then after re-charging for a good few hours the car will start again (though I don't know how reliably).

Lead-acid batteries really don't like being flattened. Flat enough to not start the car is too flat for long-term health.

Get a smart charger - CTek are one of the better brands - and just leave it on the car all the time.

TuppenceHapenny

AdrianC wrote: »

Something like this?
https://www.amazon.co.uk/Challenge-Volt-Battery-Charger-7404355/dp/B004WL7T2U

Not a smart charger, so it may cook a battery. Putting lights on to show the battery voltage is lovely, but does it cut off charging when fully charged?

Not that exact model - my one is simpler (model MCH6A) but it does have a light to show when the battery is (supposedly) fully charged. So yes, when it thinks the battery is charged it goes into maintenance mode. But I've found that often it goes into maintenance mode when the battery isn't fully charged at all and still wont start the engine. In that situation I just leave the charger connected and try again maybe 8 hours later, at which point the engine generally will start again.