12v cooler is the way to go. I've got one for freezing meat and a smaller one for grocery's I ran them for 4 days without moving my truck and had no issue cranking it. Could always get a solar charger for your battery if you're sitting in one spot for a long time.
Dry ice works great too or just using ice for a week.
Done both but after using the 12v cooler it's way better. No ice, no watered down food, no mess.
Sent from my iPhone using Tapatalk