The battery type we use for Chipolo Classic and older models is CR2025, often referred to as button battery or watch battery. These batteries in the Chipolo Classic and older models are replaceable.
In the Chipolo Plus we use a CR2032 battery, in the Chipolo Card we use a custom battery which both lasts one year guaranteed. Please don't open the Chipolo Plus or the Chipolo Card as the battery is NOT replaceable. If your Chipolo Plus or Chipolo Card didn't make it a full year, contact us via chipolo.net/support and we will replace your Chipolo Plus under warranty.