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I checked out those CALB cells. Prices and specs are similar to Thundersky, but there are a few differences in the datasheets. Thundersky's sheet is more complete, telling you how much capacity to expect at higher C-rates and lower temperatures. TS also say it's okay to charge or discharge at -45°C, versus the 0°C charge / -25°C discharge of the CALB. I can handle -25°C, but I can't accomodate a battery that can't plug in or regen below 0°C.
By far the biggest problem with both datasheets is the "standard current = 0.3C", i.e. all the other data is at 0.3C = 12A, including the cycle life data. It would take over two hours to reach 70% DoD at that C rate, and I don't know many people who drive (PH)EVs two hours a day, excluding stops and coasting.
As an experiment, I started with three bars indicated SoC and a topped off battery today. Instead of allowing the car to charge the already topped off battery for a minute before it recalibrates the SoC gauge, I tried starting off with assist.
As I expected, you can draw down the battery and the SoC gauge stays at three bars until you hit the low voltage cutoff. What I did not count on was, I also got three bars of background charging which I could only get rid of by constantly requesting assist. Background charing killed any hopes of lean burn. I'm going to go back to powering up the BCM while charging and see if the MPG improves. I got 69mpg + ~1KWh = 53mpge today on 15mi of city driving.
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