Smart watches are very close relative to your smartphones. You use your smart watch everyday because it can provide you constant reading of time, heart rate, and many more. It is natural for any battery-run device to lose its charge or battery lifetime from charging many times over and over again. Why? Because you use it everyday!
Just like your cell phone if you use them for many months constantly, the life of the battery will significantly become low. So, you will need to either change the battery or change the device altogether. But the thing is that even the smart watches of today are following the path of non-removable batteries.
So, depending on the type of smart watch you are using, you may not be able to change the battery, or you will need some expert from the manufacturer to do it for you. Anyway, let us take a walk down the whole situation.
There are two types of batteries. One is not rechargeable, and another one is rechargeable. Usually, the company warranty does not give service to not rechargeable batteries. You can take it to a watch repairer shop and change the battery.
On the other hand, if your watch has a rechargeable battery, you should be able to get it replaced. You can buy more warranty after your initial warranty expires and keep changing batteries when you need to.
The bottom line is, you can get your change or replace the battery of your smart watch.