For me, the Garmin Edge 520, v13.0 firmware appears to use exactly the same battery life as past versions.
I have two Garmin Edge 520 devices (one is my wife’s). Both with the same firmware (13.0), both with same GPS version (3.30), both with the same configuration.
If I run the two side-by-side with Garmin HR Sensor, Bontrager Speed/Cadence Sensor, 4iiii Precision Dual Power Meter, Backlight at 40%, Bluetooth OFF, here is the usage I get:
Device that went in to use on March 6, 2019 (3 months old - Total Usage: 186 hours)
Battery Usage Rate for 3h50m ride: 4.4%/hour (with Data Fields (PWR, SPD, DIS, Time, CDN, HR)
Battery Usage Rate for a 1h:45m ride: 7.4%/hour (with Map Screen on, PWR + SPD)
Device that went in to use on Jul 28, 2016 (almost 3 years old - Total Usage: 1780 hours)
Battery Usage Rate for 3h50m ride: 9.4%/hour (with Data Fields (PWR, SPD, DIS, Time, CDN, HR)
Battery Usage Rate for a 1h:45m ride: 21.1%/hour (with Map Screen on, PWR + SPD)
So, in reviewing this data with past battery life of my older device with an older firmware vs. the battery life of the newer device and my general experience with the device, I come to the following conclusions:
- The life span of the battery in these devices certainly could have been better, but in comparison to other electronic devices, the life span is not out of the ordinary.
- The Backlight uses too much power, and there should be a way to restrict it so that it does not get set to 100% by accident. At 100% backlight on a new device the battery will last 2.5 hours. There should be a way to set a backlight limit, like 70%.
- The battery life of the newer device is very similar as my older device when it was new with the older firmware.
- The battery life of my older device slowly regressed over time to 50% of what it was after 3 years of use.
- The Map Screen uses twice as much power as the other screens. I cannot, say if a firmware update introduced this issue – or if this was always the case – I just never noticed the issue until I tried to use it earlier this spring and the battery was draining at an alarming rate. The Map screen is no longer usable on the longer rides I actually need it for. Because the Battery will be completely dead in 5 hours. Changing between the Stock Garmin map and a custom map makes no difference. Navigating a course also made no difference, following a course vs. not following a course made no different for this issue.
- The battery life in colder temperatures on my older device is absolutely terrible. Anything above about around 5°C is OK, but sub-freezing temperatures results in extremely poor battery life. Granted, battery life will degrade with sub-freezing temperatures, but the battery life in my older device is much lower than battery science would predict.
From my experience the conclusion I draw is the battery is failing.
I really don’t see how any type of firmware update is going to fix these issues.
However, I would love for someone to prove me wrong, as it will save me from having to change the battery.