In one embodiment, an implantable medical device (MD), comprises: a processor for controlling the IMD； circuitry for providing therapeutic or diagnostic medical operations for a patient； wireless communication circuitry for conducting wireless communications； a non-rechargeable battery； and device power control circuitry comprising； at least one capacitor； charging control circuitry for switching between charging the at least one capacitor using the non-rechargeable battery and discharging the at least one capacitor to provide power for device operations； wherein the IMD is configured to maintain a count related to a number of times of discharge of the at least one capacitor to provide an end-of-life estimation for the IMD.
