Button battery, is a cell whose sharp and size is similar to little button. In general, this battery features large in diameter and thin in thickness.
Button battery is classified into rechargeable and primary. Rechargeable button battery includes 3.3V rechargeable lithium ion button battery (LIR series), 3V rechargeable lithium button battery (ML or VL series); primary button battery includes 3V lithium manganese button battery (CR series) and 1.5V alkaline zinc manganese battery (LR & SR series).
Regular button battery types include CR2032 computer BIOS battery, CR2025 for electric dictionary, CR2016 for electric watch, SR4, SR626 etc.