I am thinking on a way how to add cooling to the traction battery pack. I checked lot of videos about dismounting leaf batteries, even found some Russian videos where the guy was dismounting a 40kWh battery pack.
There is not much space indeed, but I think there would be a way to put some fans and a small heat exchanger into the battery pack. The fans could operate constantly while the car is turned on, it would give a better distribution of the heat across the battery cells, also would probably speed up cooling of the battery pack, since it could give more heat towards the outside. The small heat exchanger (like in the eNV200) could be attached to the on-board A/C units piping, with a valve, which is opened when the battery temperature requires it.
One controller electronics is required to sniff CAN bus messages (like battery temp, is a QC session running, etc) and start the A/C, A/C pump and open the valve towards the battery pack if necessary, so the small heat exchanger inside the battery pack could be cooled down using the A/C. This could start whenever the battery temp is above 25°C.
This will not allow to keep the temp low during QC (it definitely would reduce the heat buildup, but won't prevent it), but would allow to cool down the battery much better till the next QC. (You start with 25°C battery and <20% SOC a QC, it will bring up your temp to 45°C or even above if you charge to >80%. This kind of cooling would probably give you 3-5°C reduction, so you arrive somewhere around 40°C. But when you then start to drive, the cooling would continue and if you drive like 2hrs it would bring down the temp below 30°C, then you would get a full charge speed again.)
The only drawback is, that you have to dismount the battery pack, drill two (eventually three, 1 for the FAN controlling) holes on it to bring the cooling liquid inside, then also inside some piping, installing the FANs and the heat exchanger (find proper fans, proper size heat exchanger for the place available). This will void your warranty definitely. So the question who would sacrifice the 8 year warranty for a battery cooling?
What do you think?