@krazykid and @aredwood agree with those factors that potentially impact SOH i.e. covariates of SOH
The question is impact of each on SOH. A potential owner who wants to preserve SOH (especially 2nd hand and the manufacturer's battery warranty not available to them) wants to know how to navigate those covariates e.g.
- is fast charging only a problem if it causes temperature to rise above some threshold, or is it a threshold of number of fast charging events per X period of time?
- how does age-related degradation vary between e.g. 2011 24 kWh, 2013 24 kWh, 2016 30 kWh and 2018 40 kWh? If there's there's a big difference, then e.g. data for 2011 24 kWh batteries are of limited use when looking at 2016 30 kWh.
- if odometer is a covariate of SOH that is independent of other covariates (including number of charges, age of battery), is there a difference between going 5000 km in a year by a) driving 10 km trips x 2/day x 5 day/wk x 50wk/y vs b) 50 km trips x 2/day x 5day/wk x 10 wk/y? Or is there some threshold of frequent longer distance trips per X period of time that accelerates degradation?
At the moment, to preserve SOH, a very conservative interpretation of the data I've seen is to go short distances, rarely fast charge, newer batteries are better, avoid flooring accelerator etc. But that may be excessive, and maybe one doesn't have to do that to preserve SOH. The trouble is, we just don't know. Hence my approach now is just to largely ignore the covariates and just enjoy the drive.