12 volt battery in later i3s--watch out

[alohart]

I can relate to this. My 2018 i3 is now on its 4th 12v battery. I only have about 20,000 kms on it and the dealer says that is the reason the batteries are not lasting.

I drove our 2014 i3 only 13k miles (21k km) over more than 7 years. Our 12 V battery lasted for more than 7 years. This is probably because we stored our i3 for a total of ~3 years during that 7 years with the negative cable of the 12 V battery disconnected so that its only discharge was self-discharge which didn't reduce its charge level too much. If my driving habits were like yours, I might install a disconnect on the negative cable so that I could easily disconnect the 12 V battery while it was parked for longer periods. That would prevent the battery from discharging so much that it's life is shortened.