Battery Life/meter

I also have the Expedition, but have only had it for a bit more than four weeks so far. It seems to be quite precise in battery discharge behaviour compared to my older Fenix5 (that had a fairly non-linear discharge rate, but on the whole a bit better than specs), but since I log training sessions almost every day, the battery draw takes jumps. But these jumps seems to reflect the specifications at some 3-4% per hour of GPS, give or take, depending upon route navigation or structured training sessions. Connectivity via BT seems to draw extra battery, as do settings, map usage and lights.

I have turned off puls-ox. I have a mix of GPS only and GPS+Glonass depending upon activity. Since the previous upgrade, I have come to use battery saver mode quite a lot (with BT off, low power screen, but activity and WHR on). In this mode I get 35 days at 100% (but 34 at 99%), and discharge seems to be slightly less than 3% per 24 hours (expected). In non-battery saver mode, I get 13 days fully charged, with a daily battery consumption of some 7-8 percent given # of BT messages.

Of course the remaining number of days is reduced quite notable after a longer GPS-based session, but that is to be expected. I have NO connect IQ watch faces, and I use only the digital Garmin watch faces with few data fields. I have lights on by button only at 5% in non-activity mode and 20% in activity mode. So I have tried to find settings to minimize battery consumption.

I have not emptied the battery completely, so I still have to see if the battery discharge curve is linear across the entire charge range; 100-0%. I have only had it go down to some 30%.

In short; I currently experience battery discharge behaviour pretty much in line with specs. This said, this is what I have experienced so far. With hopes that things only will be better.

I have some more observations now: The discharge curve is not linear (at least if you keep track of the battery percentage). In the interval 100 - ca 70% discharge is pretty much as expected or even better (battery life lasting a bit longer). From 70 to 60 it is poor, dropping fast at ca twice the rate. From 60 to 50 it is much better. From ca 50 to around 40 it is about expected. From just above 40 to just below 30 it again drops fast, to be improved at lower percentages. I had it stay at 14% for 28 hours in battery saver mode (with activity tracking on), 13% for some 12 hours. And then it dropped faster again.

Since I log activities every day, it is a bit difficult to track battery consumption, but it seems to be on par with my previous Fenix 5, given my use case. The Marq do use more power to stay connected, it uses more power to sync and it uses more power during non-GPS sessions compared to the F5. On the other hand, the battery saver mode is clever. GPS power usage seems to follow specs, but GPS acquisition seems to draw extra energy at the start of the session.

I have the most recent software. 5.2.

As a side note. If I where only to observe battery consumption during one of the more steep parts of the discharge curve, it would be easy to conclude that battery life was just half of the advertised. At the other end, getting a snapshot from a part of the curve where discharge is low, would indicate twice the battery life. Or more. None true.

A problem with a non-linear discharge curve is that it may not give proper indications of how much capacity there is left. If it says that 20% (or 6 hours GPS) is left, I want it to be 6 hours left. Not 5. Nor 7.

Anyway, the non-linearity is very similar to my Fenix 5, and I usually re-chargeat around 20-30% to always have battery for a long session or two at least.