joeriv wrote:A great study!
After reading it I think there are two factors at play:
1. The battery chemistry is different.
2. The packaging for the cells was changed (not mentioned in the study).
I suggest a third factor to consider.
I think that there might be a problem in the charging and/or balancing algorithm(s). Maybe due to a change in the charger/BMS, maybe due the change in chemistry that requires a slightly different charging and/or balancing algorithm(s).
The study notes that loss goes down with higher mileage, which doesn't make sense for heat. The more you drive, the hotter the batteries, the faster the capacity loss.
Both this study and other things I've heard suggest that cars that are driven a lot are doing better.
joeriv wrote:If the trends in the study are indicative of things to come, Nissan will be replacing lots of batteries and the 40 may show similar degradation. Nissan will have to make some mods to chemistry and/or packaging to avoid future expensive warranty claims.
Yes, Nissan will be replacing a lot of batteries. Hopefully they will find and fix the issue, which might not be chemistry or packaging, but electronics/firmware.