I'd recommend a 12v fridge/freezer instead. There's tons of reliable, super power efficient, low cost options out there now(mostly the same just rebranded). A 20-36 quart size is perfect and can be run off the cars 12v outlet or a Goal Zero, Jackery, Ecoflow type power station. I've been using an Alpicool CF35 for 2 years now a few days a week and for a year prior to that used the smaller C20. In my Gen 3 Prius I had it run off the 12v battery but in my Gen 4 Prius Prime I have it running off a Jackery Explorer 500(you can use smaller) that I leave plugged into the cars 12v outlet so that it's constantly topping off the power station and allows pass-through charging of anything connected to it. You'll get tired of draining melted ice/water and crap getting soggy. You can get just about any decent 12v fridge(don't need a Dometic or ARB) for about $250 and a smaller power station for about $230.