I have been using the Fenix 3HR for the last few months which had a great battery. I have to say that in the last few days the battery of the 5 is excellent. Without using GPS and with a lot of butting presses for settings, etc. (new watch and all), the battery has only gone down 3-4% per day so far. I didn't think it would be this good, but I am impressed. Have others found the battery to be this good as well?
I am very happy for the battery life, is amazing for me too. The battery of my fenix 3 lasted 5-7 days without performing any activity.
Fenix 5: 67% since Monday with 2 hour 25 minutes of running. Bluetooth sometimes and 20% backlight.
I love this watch.
I can't be agree F5 got amazing battery life. Mine is not lasting the 20 promised hours.
I have done 3 test having at the best almost 14 estimated hours of battery life...
test 1 (no navigation, no backlight, optical sensor, glonass off)
Duration 0:52:29
Distance km 9,59
Theme light
Battery level on start 81
Battery level at the end 75
Estimated % power/hour 6,9
Estimated battery life in hours (100% to 5%) 13:50:59
test 2 (no navigation, no backlight, hr belt, glonass off)
Duration 0:46:03
Distance km 10,01
Theme light
Battery level on start 63
Battery level at the end 57
Estimated % power/hour 7,8
Estimated battery life in hours (100% to 5%) 12:09:08
test 1 (no navigation, no backlight, optical sensor, glonass off)
Duration 0:51:17
Distance km 9,83
Theme light
Battery level on start 45
Battery level at the end 38
Estimated % power/hour 8,2
Estimated battery life in hours (100% to 5%) 11:35:59
Extrapolating data from single short runs isn't the best test IMO. 81.99 to 75.0 is vastly different from 81.0 to 75.99 (2% basically). I think you should test with longer runs, or across the full range of the battery.
Extrapolating data from single short runs isn't the best test IMO. 81.99 to 75.0 is vastly different from 81.0 to 75.99 (2% basically). I think you should test with longer runs, or across the full range of the battery.
CW
Of course if isn't but it's a something. If you do the calculation with the most optimistic result (2% more) you'll get ~16 hours what still far from 20
CW is right. If you want to know actual battery life close to reality, measure it from 100% to 20% at least. Out of curiosity, maybe I missed it, what is your backlight set to?
Batteries store most of their capacity in the 90-100% charge range. That is why any battery test which does not start from a fully charged battery is not relevant. Also if you look at any device when charging (phone, watch, whatever) you will notice that it takes a short time to reach 80-90% but a longer time to actually reach 100% and show as fully charged.
Also discharging is no where near linear. The lower the voltage gets, the faster it discharges.
It's true that battery discharge isn't linear, but it follows a known curve. Therefore there's no reason why Garmin couldn't differentiate and show a percentage which relates to usage remaining rather than charge remaining.
I guess because usage remaining is very misleading as you can turn on/off features that increase usage , meaning the algorithm will have to change at any increase/decrease in battery drain.
Imo best test for battery life is to just fully charge it and use it until drained, counting the GPS / activities hours during the interval.
