Cellphone batteries should have a small switch that takes power from a small reserve battery that gets charged at the same time as the main cell. This way, when you forget to charge your cellphone and leave it on too long, you still have enough power to make that critical emergency call...
-- tspyz, May 23 2002

9V keyring charger http://www.iwantone...T=GADG&STNO=ST00640
only for Nokia, and not the 3210, for some reason. [sappho, May 23 2002, last modified Oct 04 2004]

Methane Fuel Cell for Microelectronics http://www.halfbake...ea/www.mechtech.com
Nifty alternate energy source. [quarterbaker, May 23 2002, last modified Oct 04 2004]

Isn't this what the 'low battery' alert is for?
-- angel, May 23 2002


But the "battery low" alert might not be enough to help. You can quite easily notice that your battery is running low and so not make any calls yourself, but if somebody calls you then your battery will run out. But with a reserve battery, this is kept insulated (and so cannot be run down by people calling you) until you need to make your emergency call. Croissant.
-- vincebowdren, May 23 2002


As soon as the main battery ran out, you'd just patch in the other battery. Well, I would. Would you really not make that business phone call when you had spare power just based on the very slight offchance that you might get hit by a truck and no one else would have a mobile? Better off carrying a coin for the payphone, like your mother probably told you to do. Fishboned for being contrary to human nature. Or am I just cynical?
-- pottedstu, May 23 2002


There's also technology in the pipeline (to hit the streets in late '03, maybe) that will allow electronic devices, including cell phones, to run off small methane fuel cells. So, in an emergency, all you'd have to do is find a cow . . .
-- quarterbaker, May 23 2002


. . . or else eat like a cow. GIMO.
-- neelandan, May 25 2002



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