I can speak from personal experience. I have and have used a Goalzero Yeti 1250 lead acid battery to power my system. I use it when I want the ultimate listening experience. I have written about this experience on this forum before. Think of it as a gigantic 100 lb. car battery. That's basically what it is.
My main comment is that it drops the noise floor. I listen in my basement where my baseline noise level averages below 20 dB so my environment is pretty quiet. I didn’t know I had a noise floor in my system, but the Yet 1250 somehow eliminates noise from my preamp and amplifiers. It puts out a perfect 60 Hz sine wave. I’m not an electrician but it’s made me wonder if it helps the preamp and amp to be on the exact same frequency. I don’t know. I just know it works.
The reason I don’t use it all the time is because it does eventually lose enough power that it won’t run the system. And my system is already on a dedicated line that sounds pretty good.