Your basic garage can replace the main 12v battery without much fuss. I think one should assume that 24-to-30 months is the total lifespan of the regular (passenger side) 12v battery. The smaller 12v (more rectangular in shape on the driver's side) may require dealer assistance. My 12v died in small-town VA and I had it replaced by a nice guy that had never worked on an EV, let alone a Jag EV, so there you go (nearest Jag dealer was a LONG way away). I'll probably head over the dealership and insist the other one is replaced in another month or two.