Battery life instinct solar

I’ve tried the soft reset and I’ve also done the hard reset deleting the data and fully charged it and I wore it this morning and by 1300 I was down to 20 days battery life left… 

20 days is not bad, or is it?

Well considering when I charged it fully I used to get 30days. Now fully charged it’s down to 24 days. And I’m getting that the watch is powering itself down when I’m in the middle of training or just about to save my session. 

The battery is not eternal, and the capacity decreases with the age, so having 80% capacity of a new battery, is not something unexpected after a few years. The shutting down or reboots during an activity are not necessarily related to the battery capacity, though. There are many users experiencing similar issues after one of the latest firmware updates, so I can only advise reporting it to the Support, otherwise there is little chance it gets fixed.

I had a similar problems with my instrinct solar which was just under 2 year old, as well as the battery dropping rapidly it was also crashing regularly, for example when a notification came in, an alarm went off or an activity was started. All symptoms of a failing battery; it was becoming useless. I tried soft and factory resets, different charging regimes and different software versions. In the end I rang Garmin Support (Australia) and they swapped it for a replacement watch which is working fine.

How old is the watch? The battery may be starting to degrade with age or may be faulty.

I am actually on my 3rd instinct solar. When it was new the first one would drop 40% charge each day and last 2.5 days, not the 24 promised;  Garmin replaced it under warranty within a month. The second one (described below) lasted a bit under 2 years before it was also exchanged by Garmin.

I have a spreadsheet that I use to track the battery discharge and estimate how long it will last.

When the second watch was new the estimator on the watch was approximately right a lot of the time, though it can get confused by usage patterns. So initially every day the estimate, would go down by approximately 1 day. Of course it went down by more when I recorded activites, measured SPO2 or used the backlight a lot, and less when there was a lot of solar.

I have a spreadsheet that I use to track the battery discharge and estimate how long it will last. As it got older the battery deteriorated and the estimate would go down faster, like yours. Eventually the battery would drop very rapidly - for example 20% overnight. In less than 2 years it became unusable because it would regularly crash, even though the charge was above 50%, and Garmin replaced it.

I now have a spreadsheet that I use to track the battery discharge and estimate how long it will last- the replace watch seems to be roughly correct.

The seconds display will make a miniscule difference to battery life and I've always used a display that shows them.