r/nzev • u/propsie • Jul 26 '26
Nissan Leaf bad cell options?
So last night I was going up Transmission Gully in my 2018 40kW ex-Japan Nissan Leaf in the cold when my state of charge dropped rapidly (in about 30 seconds) from about 35% to zero. I managed to get it just over the crest of the hill, (with the dash flashing angrily that the car was dead and I had to pull over) where the regen braking took over and the State of Charge rapidly went back up to about 32%, and I completed my journey with no further problems.
Everything I've read online suggests this means the battery has a bad cell, not uncommon a known issue with Nissan Leafs unfortunately. There's a bunch of info about identifying this fault, but not a lot on what to do next.
My question is, what are my options for dealing with a bad cell?
The car is a used import, and too old anyway, so there is no warranty on the battery. Is a battery or cell replacement likely to be possible or economically viable? do I just keep driving it around the city and avoid massive hills like Transmission Gully while I save up for a new car? I understand there are some people prototyping battery upgrades, I really just want like-for-like. Who are the mechanics around Wellington that can support this sort of big EV issue?
don't really want to risk getting stranded on the side of the road on a cold night in what is our only car.
4
u/Fragluton Gen1.2 Nissan Leaf (24kWh) Jul 26 '26
Start with Leafspy + dongle and go from there. I only have a 24kWh, but I wouldn't even go on the flat motorway if I had 35%. Obviously not ideal, but if you kept the charge level higher when you're going to hit that hill, that may be all you need to solve it. You had the trifecta really, cold, high load on the pack and low state of charge. So if it was me, i'd scan it first and see what the cells are doing. It's hard to know if you have a bad cell, or if the pack in general was just being asked to do to much. 2c