Our van has been in storage for the last two years. The invertor was accidentally left on and now the batteries have zero charge. I had the power connected all day, but no sign of any charging. Are they dead? Gel batteries about seven years old, hardly used.
Some chargers won't charge a dead battery. Your instructions may tell you the minimum voltage required. I think it's a safety feature to stop you trying to charge a 6 volt battery with a 12 volt charger.
A workaround that often works is to connect the charger to a good battery, start charging and then parallel connect the old battery. Once it has accepted a bit of charge, remove the good battery without disconnecting the charger from the dead one. I successfully brought the voltage back up on a dead battery recently, although it was not good enough to be usable. It's worth trying.
Some chargers won't charge a dead battery. Your instructions may tell you the minimum voltage required. I think it's a safety feature to stop you trying to charge a 6 volt battery with a 12 volt charger.
A workaround that often works is to connect the charger to a good battery, start charging and then parallel connect the old battery. Once it has accepted a bit of charge, remove the good battery without disconnecting the charger from the dead one. I successfully brought the voltage back up on a dead battery recently, although it was not good enough to be usable. It's worth trying.
Hi Collo
My thoughts are the batteries are most likely stuffed. But if you want to try the procedure above it might possibly work. But do it one battery at a time with them disconnected. Nothing much to loose.
The inverter should have switched off when the batteries got low so might not have drained them completely. But two years is a long time to sit flat however if they were not used much before, that is in your favour.
Collo,
If you have an or access to an old charger before Smart chargers came into being, you might be able to restart them but it will take a while (week or more). I've done it but it took me three weeks to do one battery.
Disconnect everything & do one battery at a time. Generally Smart chargers need >2v to start.
You aren't the first person & you won't be the last to abuse batteries by leaving them sit doing nothing - they won't reward you with long life. It could be an expensive mistake.
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Warren
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If you don't get it done today, there's always tomorrow!
I took the batteries to R and J Batteries here in Ballarat...they tested them..still had some charge....put them on their charger....all good, like new they said.
But, as every silver lining has a cloud, I suspect time will tell how well the batteries really are so don't be surprised if they do not perform like new as the weeks pass.
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Do a slow measured load. For example run your fridge and check every hour until it doesn't work. It's probably the fridge which at the end of the day is the most critical piece of equipment.
I did this for benchmarking my setup. For many hours I actually write down figures every minute.
Lead acid batteries will lose their AH capacity. They may seem ok, but if they are down 50%, depending on your type on camping this may not be an issue, but at least do a test to know what you have before you are remote.
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50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.