rrolsbe
Member
Ok, so from that description you have only absolutely proven that the car is always drawing 24A which is expected when charging in any scenario. There is no reason for the car to vary the 24A input while charging, it is a very small charge rate in the first place(in contrast to the what... 300A while supercharging...)
In order for YOU to prove battery heating is to give more information. You said "added is less than the normal 22 to 23 miles per hour" but that leaves a lot in terms of interpretation... Now I am going to guess here because I am not home to check...but theoretically, on the charging screen, I THINK the kW value on the left will be less than 5-6kW if it is heating the battery. Heating the battery will use about 3-3.5kW, so I would expect the value on the charging screen to show 2-3kW if it is heating the battery. So that would put your miles per hour of charging to show somewhere between 8-12 miles per hour vs ~22.
Can you take a picture of your charging screen when you think battery heating is occurring and post it please?
And yes I WOULD absolutely see battery heating with my OBDII adapter. I would see the motor power go to 3-3.5kW, the stator temperature going up, the battery inlet temperature going up, and finally the battery temperature going up... See the Second image HERE.
EDIT: OBDII adapter - OBDLINK MX+, Amazon, ~$79. You also need the model 3 interface cable. https://www.xtss.com/ ~$54. ScanMyTesla App $10.
The temperature has warmed up and the garage is now 50F or above. Next time I charge when the motor heats the battery at the start of a charging session, I will report the center screen MPH and KWH rates at the start of charging. I had not driven the car for a week and it was parked in the garage unplugged the entire time prior to the charging session I describe previously. It did start out charging adding about 8MPH which would be 3.5-4KWH for heating which I believe is the maximum heat the motor can provide while parked? I was not instrumented last winter to measure the power being sent through the Mobile charger. If I had to guess, when the temp gets down to where no miles are being added for 10 to 20 minutes during the start of a charging session the current will be around 14-17A or 3.360-4.080KW. I will report back to this thread later. It might be possible that if you drive the car daily, the traction battery internal temperature never drops below 50F even though the ambient temp might be hovering around 30F?
Thanks for the info regarding the OBDII interface did you also purchase the Geotab G09? is it also required?
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