5% SoC variation after standing still for some time.

[Malm]

Many times, i see on Canion a drop in SoC after driving some miles (maybe more then 15), letting the car off for some time (hours) during the day light, and when i switch on there are less 5% (always 5%, i think). This never happens when driving, or with i-MiEV on. I also saw once, a lift of 5% in SoC, after sometime off.

I think this happens because car uses battery temperature to calculate SoC. If the battery temperatures drop to some value (i don't now the value, but i will find it), then the i-MiEV add 5% of total SoC. If the temperatures rise to the same value, it takes 5% to total SoC. 10% of chances this being correct, but that's the best explanation a can find for this variation.

 

[PV1]

I noticed for a few days when I wasn't hitting full charge that after the car sat 8 hours in the parking lot, I would come back and find I've lost miles RR. I can look back in my spreadsheet to see if it was related to temperature. I believe it was the few days after taking a long drive and not having enough time to bring the car back to full on level 1.

This was before Canion.

I've noticed a 10 mile difference in range between 20-30 F degree days and 70 degree F days, but I'm not sure if it was increased drag, compensation by the BMS, or both.

 

[Malm]

Car in the garage - before charging - 22:03 pm (Portugal time)
Battery temperature - 15,6º C SoC=32% Volts=333 RR=30

Voltage - Begining charge 22:07 pm

Car in the garage - end of charge (i swich it off) - 1:30 am
T - 20,7º C SoC=84,5% Volts=360 RR=102 km

Voltage - 1:30 am

Car outside the garage -1:35 am
Battery temperature - 20,7º C SoC=84% Volts=359 RR=100 km

Voltage - 1:35 am

Carro outside garage - 8:33 am
Battery temperature - 13º C SoC=89% Volts=357 RR=107 km

Voltage - 8:33 am

Between 1:35 am to 8:33 am, without moving, without charging, voltage goes down 2 Volts, SoC climbs 5%, battery temperatures go down 7,7º C.
5%, I knew that SoC should go up 5%, everything as i thought. Temperatures going down are the cause.

Now it´s time to find the values of temperature that the car considerate to recalculate SoC (maybe going down of 15º C ???). A graph on Canion with temperature variation should help.