I was worried about my 205 running out of charge on the cross country distances and riding times last year and went to radio shack and bought a charger that I could plug it into on the bike. Took along a bunch of zip ties and on the longer days, zipped to the aerobar plugged in the garmin and bingo.

You might want to get it checked because they are supposed to be good for about 8 hours, if yours is fading faster there may be a problem.

marni