Please let us know. You don't need to worry about battery power. They are good for something like 18 hours, right? When I return from a ride, one of the first things I do after changing and showering is to upload my ride to either Strava or Garmin Connect, (usually Strava). Then, I put it on the a/c charger so it will be ready for the next ride.

Last Friday, after a self-supported century, I was too pooped and didn't have time to put my Garmin on the charger, (the rear and front strobes came first - safety is more important to me). When I needed to use it the following day, there was still plenty of battery power for a several hour ride. Unless you're doing a multi-day tour, I doubt you'll ever deplete the battery, (assuming you re-charge after every ride).