I expect I have enough bits to rig something, but I'm not sure I'd need to. I keep mine charged over 50%, and in a long-lived powercut I'd turn it off to save power. Then I'd only be using the batteries when I needed to make a call, and that wouldn't be often. With voice mail and text messaging people can leave messages for me which I can pick up by, eg, switching the phone on for a few minutes a few times a day.