Worth noting that just replacing cells on an old battery pack is kind of iffy. If the new cell has a different capacity and/or internal resistance than the old

Worth noting that just replacing cells on an old battery pack is kind of iffy. If the new cell has a different capacity and/or internal resistance than the old cells, it might not balance properly. Probably not an issue if it's within the range of what the BMS can deal with, but there is some risk that swapping cells might cause problems. Having said that, I don't have first-hand experience refurbishing EV battery packs. Someone who does this kind of repair regularly might have a better idea of what you can or can't get away with.