Battery replacement for the Huawei Watch.

I would first ask if the device is still under warranty. If yes I would go that route. If it is not, you might need to see what kind of battery it uses. Google might be able to help. If not you might need to remove the back and look. Depending on the type of battery you might have to try something like radio shack, newpower99, or maybe a batteries plus type place. Though this might depend more on what is available locally in your area.