I’ve been keeping stats on the battery life of my Band over the past few days. How does it stand up to what Microsoft claimed? Quite well. Read on to find out. All claims are taken from Microsoft’s specs page on the Band.
Claim: “48 hours of normal use” (no GPS) – Accurate!
Timespan: 33.5 hours till 30% battery left
- 100% at 9:30 PM, Oct 31st
- 30% at 7:00 AM, Nov 2nd
Usage: Probably average for most people
- 2 nights of sleep tracking
- Watch Mode enabled (constantly displays time on the screen)
- Connected to phone’s Bluetooth all the time
- Cortana queries roughly every hour
- 4 or more notifications per hour
Discharge rate per hour: 2.09% per hour
Estimate of total life: 47 hours and 51 minutes
Notes: If anything, the estimate is probably an underestimate. This is because the Band only measures percent in intervals of 10. Thus, the Band could have theoretically been at 39%, and thus would have lasted 55 hours. This test also assumes the percent reported is accurate. A true drain-to-dead test would be required for precise measurements.
Claim: “GPS will impact battery performance” – Definitely true
I estimate 4 hours max of TOTAL battery life using GPS
Total battery life: 3 hours of using GPS, 11.5 hours of combined life till dead
- 100% at 7:00 AM
- Started run/hike at 8:10 AM (using GPS)
- Ended run/hike at 11:00 AM (GPS now disabled)
- Dead at 6:30 PM
Usage: Higher than average
- While running with GPS, I left the screen on for half of the time (unusual)
- During the other half, I turned the screen off, enabling Watch Mode
- Usage during non-GPS time similar to previous test
Percent of battery used during non-GPS portion: 17.77% over 8.5 hours
Percent of battery used during GPS portion: 82.23% over 3 hours
Discharge rate per hour using GPS: 27.41% per hour
Estimate total life while using GPS: 3 hours and 39 minutes
Notes: The discharge rate of 2.09% per hour from previous test was used to calculate what percent battery was used during non-GPS portion, and thus to calculate GPS portion. Apparently “5 hours of GPS” has been thrown out somewhere, and I remember reading it, but the only reference I could find for the “5 hours” claim was a CNET article with no source attribution, and Microsoft’s spec pages make no claims about GPS battery life. Thus, while GPS life is poor, they never made any claims otherwise!
Claim: “Full charge in less than 1.5 hours” – False in my testing
Update: One of our readers says that when he charged his Band through his computer instead of wall outlet, it charged faster, within 1.5 hours. Wall chargers apparently might be slower in this case?
First time charging (0% to 100%): Just over 2 hours for full charge
- Dead battery at 6:50 PM, plugged in
- 100% by 9:10 PM
Second time charging (30% to 100%): Just over 1.5 hours for 70% charge
- 30% at 7:00 AM, plugged in
- 100% by 8:50 AM
So Microsoft’s claim is invalid for charging time, at least for my device it is. However, you can expect a full charge to take 2 hours, which isn’t terrible.
Notes: Charging was done using a wall outlet, the Nokia USB wall outlet converter from the Lumia 920, and the Band’s provided USB cable. I checked for 100% roughly every 10 minutes, thus it might have actually been at 100% at 9:00 PM and 8:40 AM, but I already left buffer room for that when saying “Just over 2 hours” and “Just over 1.5 hours”.