Solar would like to talk to you about the batteries you just insulted
Maybe it's because I'm half asleep, but I'm confused what you mean. Also I meant Capacitor Bank, not back. A common AA Battery is known as a dry-cell battery, which use chemical reactions to generate electric charge, but they deplete and become useless. If you mean like my Laptop battery, then sure, my laptop can store some power in a rather exotic device that is only possible due to the inclusion of Rare Earth Elements in it. Great for a laptop, not for a building, where the power draw would be billions of times more, assuming you have things in emergency power state. We are
lucky that our laptops can store what little power they can, but for something with more power draw then a laptop, you simply need backup power generation, not a way to store power. Unless you have trillions of dollars to spare for the purchase of enough materials to construct your own massive power storage system, that as a reminder, will bleed energy unless it is super-cooled, which defeats the purpose of storing power for a house if you have to keep it in a room that is as close to 0 Kelvin as you can get it.
What I really meant is MC power is unrelalistic. It doesn't bleed off, and is lossless if you just adhere to a few simple rules.