1. Supermarkets and convenience stores: Large supermarkets and convenience stores usually have an electronics section that includes button batteries. You can go to these stores and find the battery section, where button batteries are usually displayed on a dedicated shelf or display cabinet.

2. Electronics stores: Specialized electronics stores, such as electronics stores, mobile phone stores, and electrical appliance stores, usually also sell button batteries. You can go to these stores and tell the clerk that you need button batteries, and they will help you find the right model and specifications.

3. Online shopping platforms: Many online shopping platforms, such as Amazon, JD.com, Taobao, etc., provide button battery purchase options. You can type "button battery" in the search bar, then filter out the right brand and specifications, and choose the right seller to buy.

4. Hardware stores: Some hardware stores or grocery stores also sell button batteries. These stores usually have a variety of small tools and electronic accessories. You can ask the clerk, and they will tell you where to find button batteries.

When buying button batteries, make sure to pay attention to the appropriate model and specifications to suit the requirements of the device you need. At the same time, try to choose reputable brands and suppliers to ensure the quality and performance of the battery.