You can charge this using an adapter in your car or a regular outlet, and if you unplug it and take it on the go, items will stay cold for several hours as long as you don't open the door.
Promising review: "I bought this refrigerator because I recently started working from home because of the COVID-19 quarantine. When I’m working during the day, I have to keep myself locked up in the spare bedroom so my toddler doesn’t realize I’m home. Otherwise, she would be trying to come see me all day. **Disclaimer: I don’t just lock my toddler out and leave her alone, there’s someone here taking care of her! Anyway, since I can’t really leave the bedroom, this fridge has been great to keep some drinks cold while I’m working. I put them in already cold and they hold the temperature as long as they are in the fridge." —Aratay
Get it from Amazon for $47.99+ (available in five colors).