While doing the battery test drive for the previous post we also had the hottest day of the summer so far. Temperatures were around 28 degrees Celsius. Very hot for these parts. Just last week we had more than 10 degrees less, albeit it was particularly cold then.
After driving the battery empty in two 30+30 minute drives, with about 30 minutes in between, both the motor casing and the controller case showed an external temperature of around 60 degress Celsius. Rather hot, but the motor is rated for 80 degrees and the controller starts throttling gradually at 85 degress Celsius, so not a problem. I didn't notice the controller throttling while driving. I did curse myself for not logging it's data though. It would have been interesting.
The DC/DC converter wasn't really even warm, but the aluminum sheet that both the controller and the converter are attached to did show temperatures close to 50 degrees, so it was working as a heatsink as planned.
As for the batteries, in their closed and rather insulated case, were also noticeably warm to the touch. My infrared meter showed them at around 50 degrees. Kind of approaching uncomfortable zone, but not reaching it. I did however check how the temperature reacted while charging. It didn't go up, but instead came down to 45 degrees rather quickly and I didn't notice it going back up. All good then.