Maybe some do, but I think some of the kooleraire ones use ice. The DIY one uses ice, fans, and a heater core with pump. I agree the peltier solid-state ones won't work. I built a portable 12v mister for the pits, which would work fine in a BEV in dry climates. The mist nozzles are easily available, but they require a 100 psi pump. I could cool a 10x10 canopy for about 2 hours and 3 gallons of water off an emergency car battery.I
As for the first link Motosaurus, it looks like that portable cooler uses a "Peltier Device"