To ensure longevity, it is not recommended to allow the battery to discharge below 2.5V. Please note that due to their inherent safety, IMR cells don't have a protection circuit built in. They should never be discharged below 2.5 volts or cycle life/performance will be reduced. Maximum charge voltage is 4.25 volts. Please be sure to inspect your battery before use to ensure it is not damaged including tears/rips in the battery wrap. Discontinue use immediately if battery is damaged.