O/ T Leisure battery pd

[magister]

Have just charged my van leisure battery. With no load, it pd across it is now 14.7 volts. When drawing a couple of amps, it was still 14.5 volts.

Any ideas?

Time for a new one?

Thanks for any thoughts!

 

[Jonathan Kay]

Is it a 12 V system?

Why do you think there might be a problem?

Jonathan

 

[magister]

12 volt system, with charging from 2 solar panels. (panels off when pd measurements taken)

Used at Gurston at the weekend, but battery supply was a bit iffy - pd dropped significantly over night, causing fridge to stop working.

I suspect is it the battery at fault, but not sure how to do a definitive test.

 

[Jonathan Kay]

Those voltages are a bit high: what sort of meter?

Is it the sort that needs topping up?

Jonathan

 

[oldbutnotslow]

14.5 would be consistant with a battery that has just come off a charger and is fully charges but has not rested. 

You should expect 13.67v fully charged after standing for an hour but leisure batteries can read in excess of this even after an hour My caravan battery discharges over about 6 weeks because of the tracker and alarm which tops up from the leisure battery and as the tracker has a mobile phone connection it is constantly searching for the best connection. The last time I swapped batteries (I keep one fully charged) the viltage reading was 14.25 and that was after a day.

So nothing out of the ordinary in my view

 

By the way leisure bateries dont like smart chargers. If the volts gets too low the smart charger doesnt recognise it as a battery!!!

 

[magister]

It is a sealed type- no way to fill it up. Measurements taken with 2 different meters - digital and analogue - both gave same reading.

I suspect a new one is required.

[Jonathan Kay]

The voltage figures don't suggest failure. I'd disconnect the panels, put a known load on it (with an ammeter if possible) for a long time and measure the capacity.

Jonathan

[magister]

sounds like a plan!

thanks for the replies

Paul

[The_ASH]

It would be useful to know what the Ampere Hour rating of the battery is, what the Wattage of the panels is and also whether you are using a charge controller between the panels and the battery, this will stop excessive charging if the panels are large (above 15w). Really the battery voltage shouldn't get above 14.4v (views vary on this), my charge controller allows a monthly 'boost' charge but usually slows charge to a trickle when 14.4v is reached.

Mine isn't but a decent MPPT charge controller will get the most out of your panels, avoid the cheap Chinese ones on eBay as they might say they are MPPT but aren't, however for a simple cheap installation they are fine, just 30 to 40% less effective than the good ones and £80+ less cost.

If there is no charge controller during the day the panels will be outputting at perhaps 22v so will merrily cook the battery which is why using one is recommended.

I believe also that some van fridges (absorption ones) run flat out when on 12v but some don't so it might be worth knowing what amps it draws and whether it cycles on a thermostat when not hooked up to the mains.