Possible battery issues....

[MeonIan]

Hi all
Just wanted to pick your brains if possible. We've had our current battery for 6-7 years and in March before our first trip I took it out to charge it on our leisure battery charger, was quite surprised to see it reading fully charged after only 3-4 hours so fitted it back in. 2 weeks later as I was cleaning the van ready for the off I checked and the battery was dead flat, put it on quick charge via the van, went away for 4 nights on electric hook up so battery was charging again, no problems. 2 days after we arrived home, battery flat again however the charge indicator eye is showing green ie all okay. Bit the bullet and bought new battery yesterday and fitted it this morning, wondered whether new one comes fully charged, obviously not because I only got 12v reading on the display in the van. Now my two questions are do I need to charge this new one off the van or will our next trip in 3 weeks time top it up okay, we are on electric hook up again. Secondly how reliable are these indicator eyes and is it worth me holding on to the old battery to use as a spare because it might be okay and something on the van is drawing on it, I assume that if I turn off the 12v master switch inside the door it turns off the whole system?
Any advice appreciated, thanks.

 

[forestgump]

most van meters are not accurate only a meter across the terminals is a good way also most vans dont charge full like a propper charger so i would take it off aqnd charge and refit to van.The battery may have been on the shelf for a long time before you got it your old one may off had a bad cell to loose its charge completly and re charge (not fully as meter would show).

 

[TD42]

Last year I bought a new 85ah battery which was supposedly fully charged,the green indicator also implied it was fully charged.However I put it on charge using my Halfords leisure battery charger,& it was a further 8 hours before the charger went over to maintenance mode.
I then connected the battery up to my CTEK charger & it was anothe day before this charger indicated a fully charged battery.
as a side comment, a standard charger as fitted in most vans will not charge beyond 80% as most only charge at 13.8v which is the normal rate of a maintenance charge from a smart charger personally I remove my battery after each trip & fully charge it with a smart charger
a battery should show 12.8 on a meter BUT only take a reading at least 6 hours after removing it from the charger to allow "float" charge to dissipate other wise a false reading will be obtained

 

[waffler]

6 to 7 years is a good age for a leisure battery. I had a similar situation with an apparently charged battery, green indicator etc, that wouldn't drive my 12 v compresssor. Turned out one cell was completely gone so 12.7 volts but no current. We do a lot off mains and have digital voltmeter (£5 from maplins) to monitor charge. (There's a guide in the CC handbook.) The master switch might not turn everything off. Might leave gas ignitor on fridge live and also radio memory.

 

[plotter]

I follow all of the above as it has been on here a few times,however I never understand why the van manufacturers do not fit chargers that will fully charge the battery without the need of removal and charging with a different charger.I assume as always it is down to the usual cost.

 

[Damian]

The chargers fitted to caravans cannot be of the kind that will allow the battery to produce Hydrogen gas, that is why older vans (up to last year) are limited to 13.8v maximum.
Newer vans have intelligent multistage chargers which switch to maintainence mode once the battery is charged and this prevents it gassing.

As for new bateries, they come dry charged and need conditioning by being given a charge on a decent multi stage charger to bring them up to fully charged and ready to go.

The so called "magic Eye" only looks at one cell, it cannot "see" the other 5, so it is a gimmick and should never be relied on to give any useful information.