I bought my FR945 a week ago.
This is my first garmin watch but based on my knowledge a battery life expectancy is too short.
I got a couple of advice from other users then,
- Delete Data and reset settings, yes, I did
- Turning off all features like GPS, Pulse oxi-meter and not using Music, yes, I did
But I saw no improvement at all.
This is a record of tracked down battery drain tendency.
- After 04: 30h use (Only Wrist heart rate function turn on) - Remain battery : 97%
- After 23: 00h (Only Wrist heart rate function turn on) - Remain battery : 67%
- After 49: 00h (Only Wrist heart rate function turn on) - Remain battery : 26%
Charging time only takes 40 min for fully charging, isn't it normal?