[Ovmsdev] Cool down

[Mark Webb-Johnson]

I've been experimenting with cool down, but can't get it to work as I expect. For example, here are the results for a recent charge:

7:15pm - Ambient: 30ºC, PEM: 37ºC, MOTOR: 54ºC, BATTERY: 39ºC, SOC: 74%, IDEAL: 230km. Arrived home and plugged in (timer delayed charge, so nothing happens).
7:28pm - Ambient: 30ºC, PEM: 38ºC, MOTOR: 53ºC, BATTERY: 39ºC, SOC: 74%, IDEAL: 230km. Action: Force charge at 220V 10A.
7:33pm - Ambient: 30ºC, PEM: 45ºC, MOTOR: 51ºC, BATTERY: 39ºC, SOC: 74%, IDEAL: 230km. Still charging 220V 10A.
7:42pm - Ambient: 30ºC, PEM: 45ºC, MOTOR: 47ºC, BATTERY: 39ºC, SOC: 75%, IDEAL: 232km. Still charging 220V 10A.
7:58pm - Ambient: 30ºC, PEM: 45ºC, MOTOR: 43ºC, BATTERY: 39ºC, SOC: 75%, IDEAL: 235km. Still charging 220V 10A.
7:59pm - Ambient: 30ºC, PEM: 45ºC, MOTOR: 43ºC, BATTERY: 39ºC, SOC: 75%, IDEAL: 235km. Action: Increase charge current to 220V 24A.
8:48pm - Ambient: 34ºC, PEM: 47ºC, MOTOR: 39ºC, BATTERY: 34ºC, SOC: 82%, IDEAL: 256km. Still charging 220V 24A.
8:49pm - Ambient: 34ºC, PEM: 47ºC, MOTOR: 39ºC, BATTERY: 34ºC, SOC: 82%, IDEAL: 256km. Action: Increase charge current to 220V 48A.
9:03pm - Ambient: 34ºC, PEM: 53ºC, MOTOR: 39ºC, BATTERY: 33ºC, SOC: 86%, IDEAL: 267km. Still charging 220V 48A.
9:18pm - Ambient: 33ºC, PEM: 53ºC, MOTOR: 39ºC, BATTERY: 33ºC, SOC: 90%, IDEAL: 283km. Still charging 220V 48A.
10:19pm - Ambient: 30ºC, PEM: 41ºC, MOTOR: 38ºC, BATTERY: 33ºC, SOC: 95%, IDEAL: 299km. Charge had completed (some minutes early) and car was sleeping.

Some comments:

There was no appreciable change to the battery temperature (@39ºC) when slow-charging at 220V 10A.
Increasing charge rate to 220V 24A did seem to bring down battery temperature (@34ºC).
Increase in ambient temperature when charging @24A is most likely due to the car being in the garage, and aircon dumping charging heat raising ambient temperature in the garage.
Between 7:28pm and 7:59pm, charging @10A, the charger put 5pm ideal miles into the car, +7ºC on the ESS, but zero change to battery temperature.

Is the battery @39ºC not hot enough for cool down to matter?

Anyone know the default thresholds for Tattler, or anyone doing this manually and seen any affect?

Regards, Mark.

P.S. I'll try to drive a little more spirited, with the aircon off and performance mode engaged, on the drive home tonight, to see if I can bring up the temperatures to make the affect more pronounced. Forecast is for 33ºC ambient, and it'll be hotter than that in the city.

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