Casio has just released W-221H watches that talk about 10 year battery life:

* https://www.casio.com/intl/watches/casio/product.W-221H-1AV/

If you're willing to spend a bit more, there are solar powered watches (digital and analog faces).

Casio’s classic F91W often lasts more than 10 years, I guess they just didn’t want to advertise it til they could stand behind it.

I really like my new F91W modded by CW&T, embedded in a brick of resin so there’s no buttons, no way to change the time, no changing the battery, just a watch that will tick for 10ish years and then die.

https://cwandt.com/products/solid-state-watch

Might as well use this comment to also share somebody stuffed an ARM processor into an F91W

https://www.crowdsupply.com/oddly-specific-objects/sensor-wa...