Here we have it! Started at 6:09pm with 6rmi, ended at 1:59am with 201rmi (195rmi added over 7hrs 50mins). TeslaFi indicates 43.1kwh added. I estimate 1.3kwh was left on the battery for the 6 miles of range, for a total of 44.4kwh (not counting the buffer).
Does this seem sound?
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No. Those numbers from TeslaFi are definitely incorrect.
Your charge actually started at 6:06 as you said. We have to take TeslaFi’s word from it on the end, but likely close to 2AM.
So 7 hours 53 minutes to add 195 rated miles.
I would have predicted:
(195rmi*209Wh/rmi/0.883)/238V/24A= 8 hr 5 minutes.
So that is within 2% which is a good result and validated the method.
This formula confirms, because we know from Tesla the efficiency is about 88.3% under these conditions, that you really HAD to add only:
195rmi*209Wh/rmi = 40.76kWh
Your wall kWh (we know, with very high accuracy) was 238V*32A*7.88hr =
45.0kWh (so I would have predicted 39.9kWh = 0.883*45.0kWh added for your battery)
40.76kWh means 90.5% efficiency instead. Again, within 2% of my prediction based on Tesla’s data.
Your overall battery stats are:
40.76kWh + 6rmi*209Wh/rmi + buffer
= 44kWh (including buffer)
Or:
42kWh (not including buffer)
This is exactly as predicted above.
Realistically the method probably has about
1.5% error, so say +/-0.5kWh.
Compare to charging constant prediction of:
219Wh/rmi * 201rmi = 44kWh (including buffer).
Thanks for doing this. This confirms definitively that those rated miles are usually very accurate, and definitely are in your case. There is no chance that you have energy “hiding” anywhere.
You have 44kWh vs the original 48.2kWh, so no question: 8.8% capacity loss.
You used 45kWh from the wall at 90.5% efficiency to add 40.8kWh of energy to your battery, taking it from 6rmi to 201rmi (195rmi added).
I think this is reasonable, though somewhat on the low end of users.
Your BMS is completely calibrated, it appears.