Yesterday i charged my pebble c2d for the second time. Got the watch at 80% charged it to 100% then drained to 30% over 12 days, then charged it up to 62%.

What’s weird is after charging, my reported battery kept going up even when not on the charger. It was at 74% 8 hours later. I restarted the watch and it showed 88% immediately and then has since dropped to 87%. Anyone have any idea what happened here?

Edit: Guess I can answer my own questions with some research. Love having access to the source. Older watches use a linear voltage table with some debounce logic. These new nrf based devices use Nordic’s fuel gauge library with coulomb counting. So, it’s an adaprive algorithm that learns over time. Only issue is calibration takes discharge cycles, but with a watch that discharges over weeks, not days, that can take a while as I’m on only my second discharge cycle, and even then not a 100% cycle. Oh pebble problems ;)

I’m guessing if i had waited for a full charge that also would have helped.

Source: src/fw/services/common/battery/nrf_fuel_guage/battery_state.c