In a hot climate, I think few options will offer much relief to force cool the battery unless you are willing to go I to the case. (I guess that leaves a drive to Mt Hermon for some cooling (Shavua Tov).
For cool climates, i found that 3 hours of passive cooling while driving efficiently at highway speeds does almost give you enough space for a reasonable charge. The issue is the top of the pack doesn't have any real airflow, so my curiosity is whether a smal fan mounted under the center rear hatch could help push air over the top of the pack (even just a little)to give me just a little more thermal space. I saw someone on facebook suggest placing cloths between the top.of the pack and the car, then using a spritzer to pull heat via the case. I don't like the idea of pouring water around the battery, even if sealed. My fear about dry ice, is that if the co2 leaks back into the cabin in volume, that might not be good for alertness.
2019 S Plus (93.3% SOH) & 2019 SV Plus (89.9% SOH) Both Silver
2013 Leaf SV sold 2019 with 11 bars
100 Mile Club Member (Number 87)
Max Miles on 13 Leaf: 120 miles
Max Miles on 19 SV+: 242 Highway miles @ 4.5 miles/kWh