Temperature Based Capacity Degradation

I am far from an expert on this, but I did do a little research that I'll share here. It seems like every car has different curves, but since I aim to either be generic, or self serving I'm going to share both averages, and F150 Lightning specific details. I am also focusing on "observed" vs "EPA rating" as the whole point of this calculator is to be better than the GOM

• The ideal operating temperature of an EV is about 80-85F/27-30C. F150L is a bit of a range instead of a peak: 70-90F/21-32C
• Going over that ideal temp seems to be 1% of degradation for every 5F/3C, 1% for ever 10f/6C for the F150L
• Going under that ideal temp seems to be 3% of degradation for every 4F/2C. The F150L seems to hold true to this once you dip below 70F/21C

So, to apply this use the degredation options. First figure (or guess) your overall battery SOH. If your EV or just the battery is brand new, it's safe to assume 100%. Otherwise it seems like 2%/year of age is a decent average. Maybe a bit more if you DCFC all the time, a bit less of you never DCFC.

So in my 3 y/o EV my degradation option should start at 94%, then I figure I'm going to be traveling in 40F weather, so I reduce it another 30% and set it to 64%. For my F150L I start the drop off at 70F so really only need to nock 21% off which means 73%

This is a rough guide, so please determine it's accurate for yourself and let me know via the forum link if you think I should alter any aspect of it.

These figures are factored into a calculator here

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