Leisure battery won't hold a charge (even disconnected)

Have I broken my leisure battery? We hadn't used the van for about three weeks and when I checked it the day before camping the leisure battery showed 1v. I put my normal car charger on it for a few hours and it showed fully charged. Off camping to our favourite spot in the woods and we couldn't get the propex to fire up. Checked the battery 11.2v. Started the engine and checked again 13.5v so split charge system is ok. After we got back Sunday I removed every fuse in the leisure circuit so the leisure battery just fed the positive side of the empty fuse box. Checked the voltage Sunday night 12.12v but that was after a 2 hour drive home. Checked it again today and it shows 11.89v.

 

If it drops that much you need to make sure the battery is put on a charger that can charge from 0v, As some only do from around 3v like the c-tek. You'll probably find that the battyery was showing that voltage but was only a surface charge and not a deep charge.
I had the same problem on one of mine at christmas and this is what I got told, Luckily the shop I brought it from got the initial charge in it for me then to connect it to the c-tek. I then left it on for 2 days to fully charge.

Scott,.

 

You could try fully charging it, then put a load on it, i.e. Headlights on, and see how long it lasts.
sounds like $$$ to me
Tony

 

Cheers for the relies. I seem to remember reading somewhere that the voltage figure does not really tell the whole story about how good a battery actually is.

 

Charge it up check the voltage should be around 12.8 to 13v disconnect it if its dropped more than a 0.5 to 1v over night its had it.

 

kwik fit will be able to tell if its dropped a cell. But again as per the replies charge it properly and then use it to see how quickly the voltage drops.

Happened to me not so long ago. I got my new one off line. Saved about £50

 

Get a cheap hydrometer and check each cell. If one or more are down, its likely had it.

 

my old LB died a death and I got a new one ... I now leave it in the garage on a trickle charge when not in use to keep it topped up

 

If you have a split charge system if you take the leisure battery out what do you do with the cables/connectors if running without leisure battery in??

 

I would disconnect the relay live Barney

 

cheers mike ok so IF my leisure battery is knackered?? and its connected ,will this likely knacker my main battery in the end??

 

not if your split charge is working ok and diconnecting the two batteries when you turn the engine off.

 

mmmmmmmmm not sure which way to go now . Be back later just going to auto supplier to see if my main battery was knackered or its not coz he tested it for me last night . :-

 

Me main battery must a been knackered coz hes given me another, trub is i heard um out back saying oh its not a dodgy lot is it :- which has put doubt into my mind about trusting it :-

 

A shorted cell on the leisure battery will stop the main battery charging as the voltage across both batteries wont go to the 14 volts or so that proper charging needs, when the split charge relay closes.

And once batteries are left flat be they leisure or starter the acid concentration causes sulphation. You end up with a battery that shows all the right voltages but has a low capacity and high resistance.


Keep the battery trickle charged and it will last years. Let it go flat once or twice and its dead.

The other death of batteries is the charge cycle causing material to fall off the plates and fill up the space provided by the manufacturer below the plates when the cell shorts out or discharges quickly.

 

Charge up the battery as before, then make sure all the leisure circuits are switched off. Remove the negative terminal and fit an ammeter.

Is there a drain?

 

well I disconnected the battery and put it on charge for almost two and a half days. I just took the charger off and now the battery reads 13.90v. We'll see what it is in a couple of hours.

 

Just checked it again and now it reads 13v. I think that's bad!