BoltEV wrote:SeanNelson wrote:BoltEV wrote:...how do you suggest I take that measurement now?
I described the method in my first post in this thread.
Yes, I recall, but your method requires that I have a comparison measurement to when my car was new, which I never took.
Hint: skip the 'comparison' portion - you simply measure capacity, not capacity loss.
SeanNelson wrote:To get an idea of capacity loss, you'd have to look at the state of charge of the battery at the end of the drive, use the kWh to extrapolate the total battery capacity, and then compare that to the same metric from when the car was new.
For example, if you had a 5% charge left at the end of that trip, and assuming that you started with 100% charge, that means that the 55.5kWh you used for the trip represents about 95% of your battery (100% - 5%). That, in turn, would tell you that the battery has a capacity of approximately 58.4kWh (55.5 / 0.95). If you could compare THAT number to a similar measurement taken when the car was new THEN you'd have some indication of capacity loss.
In practice, the capacity figure you get by doing this bounces around somewhat, so you'd have to take the average of several readings to get a sense of what's happening with the battery.