Maximizing battery life on the Mini 2

Here’s the link to the battery guide. 

support.garmin.com/.../

The Mini 2 inexplicably lacks the extended tracking (sometimes aka expedition mode) option. I guess Garmin believes that the battery life is so much better that it is not necessary.

If you want to maximize battery life, you will have to turn things off individually. Relevant things include:

Display: Set timeout to the shortest possible value. Set brightness to zero.

Inreach Remote. Turn off. Disables ANT+ radio.

Phone. Turn off. Disables the BT radio.

Tracking: Set send interval to the longest value consistent with your use. Off if you do not need real-time sent points. When stationary, the device automatically sets the send interval to 4 hours (if sending is on). However, it will check at the original sending interval to see if you are again moving. The check uses only the GPS radio, but still - if the original send interval is short, you are using battery frequently to acquire that fix.

Activity recording: Set to Standard. High detail runs the GPS radio more than you'd like.

GPS: I have no idea if multi-GNS uses more, less or the same amount of power as GPS.

There is no way to change (or avoid) the once-an-hour active message check. This can be a real battery suck if you are in challenging conditions. Once the unit initiates the active check, it (re)tries very hard to complete the check. This is why indoor (or even windowsill) tests are a bad idea.

In general, you should carry the device in a manner which maximizes sky view. Do not bury the device in your pack. Do not carry it in a short or pant pocket. Best possible place is high on your shoulder - say on a pack strap. This minimizes interference from your body.

The first day I noticed that when i'm inside or "reasonably unobstructed view of the sky" i could see it drain. Especially when first turning it on after it was charged to 100%. It dropped down to 98% pretty quickly, but then slowed.

However, yesterday I went on a test 3.5 mile walk (about one hour with full sky view the entire time) and it didn't go down even one percent.  I used standard activity recording level and 10 minute send interval. I disabled phone connection (Bluetooth). I disabled remote (ANT+).

This week i'll be testing again with Multi-GNSS enabled to see if there is a difference at all.

so lesson for me is: use outside only, only connect to phone when really necessary to sync or message, then close explore app and disable connection.

I really appreciated all the feedback. For the most part, I do have my settings similar to what twolpert suggested ... with the exception of bluetooth being on.  My guess it is the partially impeded view of the sky that is causing the device to churn and eat up the battery.

While I did get the Mini 2 for an upcoming March Arizona Trail thru-hike (presumably with mostly unimpeded views of the sky), the majority of my hiking is in the White Mountains of New Hampshire and Maine with significant tree cover.  

Tomorrow, I'll be on a 8 mile (forested) hike and try again with these suggestions -- including turning off the phone connection (but tracking at 30 minute interval).  I'm hoping this will give me a better test than through my windows.  Will report back.

I really wish there was a way to turn off the automated message-checking feature - perhaps similar to turning tracking on/off?

Again, thank you guys...

-RPR

I had an Mini 1 and have just upgraded. I have been very pleased with the significant improvement to the GPS sensitivity performance which was quite poor on my Mini 1.  The removal of extended tracking does seem strange.

My testing on battery life shows that the Mini 2 attempting unsuccessfully to contact the iridium network can consume many percent of battery life per hour. Other comms factors seem significantly less important. You get a warning chirp (too quiet) / onscreen message that the unit is unable to communicate via Iridium after about 20 mins but the drain is pretty horrible. Just forgetting to turn the unit off if it is safe in your pack overnight will cost a lot of battery.

I will leave the unit unable to communicate for 24hrs from fully charged and observe its behaviour. Will report back shortly after I am back from a trip away this week.

Dave

When I first got the Mini 2 I charged it up and left it on in the house next on a 2nd floor window sill. It drained completely in less than 24hrs... That worried me. But on a 5hr hike in a forested canyon with full tracking and multiple messages sent and received, the battery used only about 11%. 

Hi Steve - thanks for input. I agree the battery life is pretty good when you have clear sky view.

We all know this is a primarily an emergency device so I guess having it make repeated attempts to communicate is fundamentally important. Just got to remember if you're on a long hike to switch if off overnight or to ensure clear sky coverage.

BTW: I have identified an apparent problem with tracking freezing (s/w vers 3.10). Whenever I switch into the Tracking view my track distance freezes (time keeps rolling) and it only recovers when I return to Navigation view. Tracking works flawlessly if I do not switch away from any of the three Navigation widget views. I will search the forum for other users with the same issue. Have you seen this behaviour?

Dave

OP back again.  I’m presently section hiking the Arizona Trail and I am generally pleased with the device.  The AZT has minimal tree cover and that, plus (1) turning the phone connection to ‘off’ until Explore is needed for messaging, and (2) turning it off every night has meant that I have excellent battery life (e.g for one 5 day chunk, I still had 85%).

I have found two quirks that others have mentioned : (1) tracking is uneven and (2) incoming messages on the Explore do not display (probably sync?).  Regarding tracking, I sometimes hear the chirp and mostly I don’t.  Back home, my wife is not seeing all the tracking points.  

That said, what works the best for my family are two presets: ‘leaving camp’ and ‘made it to camp’ - all the tracking points are  just nice to haves (unless something really happened).

Hope this update helps others.

-RPR

In rereading this thread, I see that I neglected to mention problems with the typical windowsill test. At best, the windowsill is going to give you a 180 degree sky view (half). Remember that the GPS constellation changes over time. The net result here is that the fix is subject to very fast transitions from one location to another. These excursions are frequently sizeable. 

For example, if the device is sitting on a north-facing windowsill, you will see substantial excursions to the north. Very occasionally to the south. If you view the points on the map, you will see a characteristic spiderweb pattern.

Even when stationary, the device checks for "movement" at the currently set sending interval. For example, if you are set for 10 minute sending, the device will check its location every 10 minutes. In the presence of the large excursions, the device will detect motion very frequently. Every time, it will send at least one track point (for the apparent endpoint of the excursion). 

Bottom line is that the device wants to send points frequently. And the 180 degree sky view means that there will be problems with the send. There is only one Iridium satellite in (good) view at any given time. When the device can only see half the sky, it will sometimes not SEE the Iridium satellite. The device (re)tries very hard to complete a send. Lots of battery-eating use of the Iridium modem.