Originally Posted by
DaveB624
It seems that my 36v battery has only 2.75 volts from sitting all winter (my stupidity). Is there any way to bring it back. My charger doesn't touch it.
A BMS will refuse to charge such a heavily discharged battery, you need to get some volts in there for it to be recognised as a good(?) battery. If you can access the internal connections you can try manually charging each parallel set of cells* with something like a bench PSU - the aim is to get each set over about 2.5 volts, maybe as much as 3.0 V, so you can resume use of the supplied charger. It may be that this process works and you have a working battery (with less life than it had last year) or it may be that some of the cells are so dead you have to open the pack and replace some, or just throw the whole thing in the recycling.
* Risk of serious injury or death: fire and explosion, toxic fumes and corrosive liquid - don't do this without taking appropriate safety precautions.