Light is absorbed through the face of the watch by a solar cell beneath the face, which changes the light into energy that is then stored in a rechargeable lithium-ion battery.
The Lithium-Ion batteries are fallible, whether they are in phones or gadgets, but with a little conscious effort, you can easily get two years out of a battery.
Rechargeable lithium-ion battery that allows up to 10 hours of continuous play.
One negative aspect I find in the Micro is the Lithium-Ion battery.
It uses a rechargeable lithium-ion battery.