I have during the last month tested the Garmin Instinct Solar and in this article you can read about my experience with the outdoor-watch which in principle has an endless battery life.
Garmin Instinct 2 Solar review: smartwatch promising unlimited battery life, Smartwatches
Garmin Instinct 2 GPS Watch Review
We Tested and Reviewed Garmin's Indestructible Instinct Smart Watch
Garmin Fenix 7 Pro Solar Review
Garmin Instinct 2 Solar review: Running on sunshine
Garmin Instinct 2 Review
Garmin Instinct 2S Solar: Tried and tested
Garmin Instinct 2 Solar review - 220 Triathlon
Garmin Instinct 2 Solar Deep Dive - Outdoors Magic