martyscholes
Well-known member
I had read quite a bit about the back-to-back DC fast-charging problems, but did not experience it until yesterday. I intentionally took a 400-mile road trip from Colorado Springs to Flagler CO, to Colby KS, then back. The first charge in Flagler started at 43 kW, taking about an hour to get to 94%. In Colby, the charge started at 24 kW (roughly half) and took about two hours to get to 94%. Back in Flagler, the third charge started at 16 kW, taking about three hours to get to 94%. I noticed that the battery after the first charge was quite hot with the gauge showing the temperature right up to the red line, but showing no red. Ambient temperature was about 35 degrees F.
Since I had plenty of time during the third charge, I did a little bit of reading. It seems that Nissan engineered enough cooling to remove the thermal energy generated during driving. Even though driving consumed about 25 kW on the open road, the air flow underneath the car was enough to remove the heat. Nissan also engineered enough cooling for 6.6 kW overnight charging even in still air. Nissan even engineered enough heat capacity to absorb the thermal energy generated in a single rapid charge while the car is sitting still (no airflow). It seems that Nissan did not engineer for still air while rapid charging a hot battery, made hot by the previous charge. Rapidgate is still a thing, at least in my 2019 SL 40 kWh.
A part of me understands why Nissan did this. The cost and complexity of active thermal management would be a benefit only in multiple rapid charging trips. Honestly, those types of trips are relatively rare. Even so, this is not a car for road trips.
Since I had plenty of time during the third charge, I did a little bit of reading. It seems that Nissan engineered enough cooling to remove the thermal energy generated during driving. Even though driving consumed about 25 kW on the open road, the air flow underneath the car was enough to remove the heat. Nissan also engineered enough cooling for 6.6 kW overnight charging even in still air. Nissan even engineered enough heat capacity to absorb the thermal energy generated in a single rapid charge while the car is sitting still (no airflow). It seems that Nissan did not engineer for still air while rapid charging a hot battery, made hot by the previous charge. Rapidgate is still a thing, at least in my 2019 SL 40 kWh.
A part of me understands why Nissan did this. The cost and complexity of active thermal management would be a benefit only in multiple rapid charging trips. Honestly, those types of trips are relatively rare. Even so, this is not a car for road trips.