66i Battery

I’m curious to see everyone’s thoughts on their battery.  As I posted in the SD Card post, while I was downloading maps, I lost about 30%.  As the other poster said, it’s not likely real world results and it’s best tested in the field.  I will be watching mine and posting what I see, but I’m curious with others.   So far I still feel it’s dropping quicker than previous devices, but time will tell.  

  • For standard use cases, it does have lower run time than other inReach devices. Anecdotally, my experience matches up with Garmin's claims (35 hours at 10 minute send interval). I haven't run enough tests to be able to verify the 200 hour/30 minute interval in power save mode. However, my experience indicates that battery life is much, much better in power save mode.

  • Thanks for the observation on yours.  Thats good news, it the advertised claims of 35 hours can be obtained, then all should be good. 

  • hey there, i'm trying to get an idea for how long the battery can last with logging only, no uploaded tracking. Tried to contact Garmin but they didn't really have a number for me and everything I see relates to tracking interval setting and expedition mode (which if I understand correctly logs a less accurate gpx track). I'd like to use it to track my progress as accurately as possible while doing trails, but only rarely (and manually) upload a tracking point (say at the beginning and end of a hiking day). Do you have any idea how many hours it would get in this manner (screen off, just used to check progress, no bluetooth, etc)? any insight would be appreciated, thanks!

  • This is going to depend on how you configure the intervals at which points are logged. This is just like any other Garmin handheld. You can choose among auto, time or distance. Most likely, time is the only method which will allow you to explicitly control GPS radio on-time. And that’s the major consideration for battery life in your scenario.

    I’m not sure about the 66i. On any other iR device, logging at 30 seconds or less causes the GPS radio to remain on constantly. 

    Edited to add: Based on the description of expedition mode, best guess is that it’s a modified version of auto. Probably akin to or worse than “Least Often”.

  • Thanks, do you have any idea how many hours it would last with whatever the default logging setting is, only doing the GPS tracking? I'm assuming it would have to be longer than with uploaded tracking turned on but difficult to get an idea of how much longer. 

  • I have no idea. I've never actually tested it. I would guess that the battery life in your scenario (battery save mode so the screen is off, no sent track points, no WiFi or BT, no ANT+) is going to depend mostly on the way it handles the GPS radio. And auto is extremely opaque - there is no way to guesstimate because you can't tell what it's actually doing under the hood.

    Best bet is to get out and test it. I suspect that the auto mode is adaptive, so a static test (device standing still) is likely to be inaccurate. 

    Frankly, with the limited battery life in this device, I'd want something like a solar charger if I was going to be in the back country for an extended period of time.

  • I wound up ordering one and it's on its way, will have to just try it out.  I really only do 3 or 4 days at a time so far, so I'm hoping I can use it to track my route and check progress when hiking and leave it off at night without having to worry a lot about it dying on me. I don't want to have to add a charging device for it to my kit as I don't use one now. Time will tell... Thanks for your quick responses!

  • You might want to check the screen brightness on your device.  It seems that the unit strait out of the box is set at max.  This might be necessary in very low light conditions but for most of the day is not needed.  You can increase your run time significantly by turning the screen brightness down to almost nothing which will work fine for most of the day.

  • Recording tracks for a few hours per day in expedition mode and turning the 66i off at night, I get at least a few days out of one charge.

  • Switch off Wifi and Bluetooth to increase life? Works with phones so should here too?