All rechargeable batteries gradually store less power with each recharge. Shimano’s lithium-ion battery, however, provides up to twice as many recharge cycles as most competing batteries. The norm for an eMTB is about 500 charge cycles. Shimano’s battery unit is designed to provide 1,000 recharges before it reaches the point at which replacing the battery is advised. At that point, the battery will hold 60% of its capacity vs. when new.