ozzyb
Member
We have 2 house batteries with a solar panel charger to keep things topped up when we are away. Recently one of the batteries is over charging. Just changed the charge controller but still same problem. Any ideas please
Hot over charging battery problem
- Thread starter ozzyb
- Start date
macd
Active member
Could be caused by one of the batteries losing a cell. The charge controller then sees the low voltage and keeps trying to pump in more. Suggest you disconnect the batteries and check their individual voltages.
VicS
Well-known member
Shorted cell ?? If your battery is getting hot your charging system must be rather OTT for keeping the batteries topped up.
Check the volts on the suspect battery after it has stood for 24 hours disconnected with no charge or load. If its a shorted cell you will only see around 10.5 volts
ozzyb
Member
I've changed battery. The disconnected battery recovered. But the replacement is now over heating. Solar panel covered, no charge and still hot.
macd
Active member
Odd. Can you confirm that the "2 house batteries" were connected as a bank in parallel with each other. That's what I (and Vic, I imagine) presumed to be the case.
What's the status of the battery you haven't replaced (temperature whilst charging, rested voltage)?
ozzyb
Member
Temp of other battery normal. Just disconnected batteries. It is possible that it's a dud cell on the hot battery . I'll leave it a while and double check. Other battery 12.75v and ok temp.
jordanbasset
Well-known member
Had a problem with one of my two batteries (connected in parallel) overheating. After much mucking about with the charging system changed the overheating battery (it could not hold it's voltage after an hour rest) as the other seemed to be holding it's voltage okay. Within a couple of days the other (old) battery also started over heating. Changed that one to and no problems in the 12 months since
ozzyb
Member
Seems similar. I've changed batteries but I have possibly mixed up the older 2 batteries and not fully eliminated the offending battery. Getting there.. Thank for help.
ozzyb
Member
Just because there's a green eye on the battery window doesn't mean it's good despite what it says on the battery. My mistake mixed up batteries green eye was a dud. Black eye was the ok battery.
matthewriches
Active member
Anyone near you able to put a load tester on them? Or a local motor factor will usually do this for free. That’ll give you a conclusion.