I've been digging into the CAN bus trying to read battery state. Here's what I have so far
SOC is available as percent ModePID: 22005B. Standard vehicle PID for SOC does not return data.
max SOC 84.313728. For the rest of the post, I will instead refer to these as decimals ie. 0.84313728
min SOC unknown. Determined one of two ways: (MAX_PCT - 65%) or (16.5*MAX_PCT-10.2). I use the latter.
Polling for SOC every 3 seconds gets the best results. It sometimes gets updates while the car is off, the updates are more frequent when the car is on.
Based on 100% SOC = 16.5kwh, each 1% of SOC should represent 0.165kwh. However, when I try to compare percentages to kwh usage based on knowing the current charging rate, the numbers are insane.
So based on this table, except for the last one, I'm getting 2x the kwh per pct that I should be. Which makes me think SOC is highly inaccurate. I've thought about switching to looking at HV volts/amps directly, but haven't done as much research on it. Has anybody else tried to determine battery status by looking at CAN data?
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