It would be great if used as an "emergency power source". I see this equivalent to the satellite SOS systems - not useful for daily use but essential in emergen

It would be great if used as an "emergency power source". I see this equivalent to the satellite SOS systems - not useful for daily use but essential in emergencies. You know you can get brief emergency function every x hours. But for the question asked higher in the thread, it would never be comparable to a "real" battery. This would be a very special purpose battery.