We have Ecoflows and they're great for keeping the internet on when the power goes out, I have one I can actually boil a kettle of water with! So I kind of know what the size vs output ratio is and my concern is these units seem too small. Unless you've solved the heating problem you need some ventilation and a fan?

They look cool, but it would need to be a bit bigger I think to realistically power an appliance like a refrigerator. And also, can you boil a kettle with it?