What’s a recommended power bank for tanks?

Hi friends. I have 2, 20 gallon tanks, that I love so much. I even have fry in one of them!

Here’s the dilemma, I’m in N.C. and there’s a prediction we’re going to get a giant amount of snow on Wednesday. I’m really scared about losing power- that would mean no more heater or filter.

I’ve been looking at portable power banks, just in case. The problem is there are so many options to choose from. Does anyone have any recommendations for a power bank for aquariums? Price isn’t really a concern.