Thread: Deep Cycle 12V Caravan Battery

Originally Posted by Bos

I got given one of these the other day to compliment the 12v system we run in our hut. Problem is its dead flat and modern home-use battery chargers Ive tried dont like it
Anyone know if this is recoverable or is it a visit to the scrap metal buyer
Thanks

Try connecting it up to a small 12 volt trickle charger, One without the brain that tells itself the battery is fucked. After a day or two it may take just enough charge to then be recognised by the smart charger. Even try connecting it to a medium sized solar panel (50-100 watts).

I have several car batteries that were classified as fucked, that I have running energisers around the farm. Connected up to a 120 watt panel with charge controller, they have worked fine for another 6 years. Still working today.

Appreciate all the comments and advice.
As it was given to me, got nothin to lose in trying to restore it.
I was told that a 24v charge into it for the first 12 hours would restore it enough to then handle a 12 v charger. At any rate, I'll give a few of the above options a go and see what happens

Originally Posted by Bos

Appreciate all the comments and advice.
As it was given to me, got nothin to lose in trying to restore it.
I was told that a 24v charge into it for the first 12 hours would restore it enough to then handle a 12 v charger. At any rate, I'll give a few of the above options a go and see what happens

Err no. If its a flooded deep cycle 12 volt battery putting it onto 24 volts will just boil off all the battery acid and fuck the battery properly. I HAVE put a seemingly dead 12 volt deep cycle onto 24 volts, but only till the ammeter showed it was taking a charge (15-30 min). Then back onto the 12 volt program.

If its a more expensive gel or AGM, the battery will simply start bulging (hence Mimms2 wanting a video taken) or squealing. The resultant gas bubbles in the gel push the gel away from the plates, and that part of the battery can no longer hold a charge. So your 100ahr battery rapidly becomes a 25ahr one.

I've always wondered about those desulphaters??? as that's the untimely end to most batteries. Sulphation.

Originally Posted by Bos

Appreciate all the comments and advice.
As it was given to me, got nothin to lose in trying to restore it.
I was told that a 24v charge into it for the first 12 hours would restore it enough to then handle a 12 v charger. At any rate, I'll give a few of the above options a go and see what happens

Havent read past this, so someone else might've suggested the same: I've had good results connecting a large, fully-charged battery to the dead one, then a charger onto the good one for a couple of days. Once it accepts charge (and charges up), work it hard ie wind over something in 1stgear. Run it down a bit, then hard-charge again before putting into service. I have 2x 400cca batteries going strong a year after they were deemed scrap. This was advice given to me , specifically for gel-mat batteries, but worked equally well on the lead-acid. Worth a shot

Went to start the mighty Outlaw up, and dead flat battery. 2 volts. Gel. Smart charger didn't recognise it. So did your trick and jumpered it in parallel to a 200ahr I have at full charge. Overnight it rose to 10 volts. Now on trickle charge in the smart charger. Wonderful! Will see how it fares tomorrow at the Kuratau quad bike ride. Go the might ktm RFS 525 motor