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Calculating the battery pack capacity

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Today I checked my battery pack capacity by using the data provided in the "Since last charge" tile and found i was down 5kWh of capacity. First here's how I do the calculation: Miles driven * Energy used per mi divided by the change in SoC. For me the numbers were 72.8 mi * 319 Wh/mi/(.9 - .57) = 70373 Wh. I have a P3D and about 5400 mi on the car. Can others do a similar test and calculation and post your results for comparison.
 
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No calculations like that can actually measure battery degradation because there are too many approximations going on within the cars computers. The cars seem to have about 3% degradation the first 6-12 months. The batteries start out at about 77.5 kwhs so they settle in at about 75 kwhs. There is engineering access to the capacity but that is not available to the user and Tesla is unlikely to divulge it. Don't worry about it.
 
Today I checked my battery pack capacity by using the data provided in the "Since last charge" tile and found i was down 5kWh of capacity. First here's how I do the calculation: Miles driven * Energy used per mi divided by the change in SoC. For me the numbers were 72.8 mi * 319 Wh/mi/(.9 - .57) = 70373 Wh. I have a P3D and about 5400 mi on the car. Can others do a similar test and calculation and post your results for comparison.
Garbage in, garbage out.
 
I believe that it has been recently reported that squirrels have been able to get into the battery packs of some Model 3s and that the evidently have a cavernous appetite for the 2170 cells. While squirrels were known to get into Model S/X wiring, evidently the different chemistry of the 2170 is better than wires.

So maybe they've eaten some of your cells, reducing your capacity.