Heart rate monitors from Garmin, Wahoo, and Polar rely on consistent power delivery to track cardiovascular data during training sessions and races. The CR2032 Battery from Energizer provides 3 volts and 235 milliamp-hours of capacity using lithium manganese dioxide chemistry in a 20mm diameter by 3.2mm thick coin cell. Garmin's HRM-Dual heart rate monitor runs for approximately 3.5 years on a single CR2032 assuming one hour of daily use, while the HRM-Pro lasts roughly one year under similar conditions. This same battery powers SRAM's eTap and eTap AXS wireless shifters across road and mountain bike groupsets, with each shifter requiring one CR2032 that lasts approximately two years based on 15 riding hours per week.

The battery maintains stable 3-volt output throughout its discharge cycle, preventing the voltage drop that degrades sensor accuracy as batteries deplete. Lithium chemistry operates reliably from -22°F to 140°F, handling winter base miles and summer training camps without performance degradation. The 10-year shelf life allows you to stock replacement batteries for multiple devices without degradation concerns during storage. Each battery weighs 3 grams and serves as a direct replacement for BR2032, DL2032, ECR2032, 5004LC, and ST-T15 designations across different device manufacturers. SRAM specifically recommends avoiding CR2032 batteries with bitter child-safe coatings, as the coating material can interfere with terminal contact and cause shifting performance issues.