Abstract: A system of optimally recharging a battery cell while powering a device connected to the battery pack, in which an electronic switch connects a battery pack power-output either to the battery cells or to a second power-input contact. When not recharging, the battery-pack power-output contact is connected to the battery cells, thereby powering the device from the cells. When recharging via a charging unit, the battery pack's power-output terminal is uncoupled from the cells and coupled to a power source of the charging unit, thereby powering the device from the charging unit. At the same time, a voltage is supplied to the battery cells, thereby recharging them. The switching may be activated by a voltage supplied by the charging unit to a temperature monitoring thermistor in the battery pack. In this way, the battery pack's power output may be automatically switched whenever it is placed in the charging unit.

Abstract: An apparatus and method for monitoring and storing a status of a rechargeable battery pack in which the battery pack status is monitored by a device while the battery pack is functionally connected to that device, and then periodically updated to a non-volatile memory in the battery pack. The non-volatile memory may be connected in power isolation from the rechargeable cells, thereby ensuring that the battery is not drained during long periods of storage. The battery pack may also have a latch, which has to be released in order to remove the battery pack from any device to which it can be functionally connected. Releasing the latch may cause the battery status to be written to the non-volatile memory, ensuring that the battery's memory has up-to-date battery status information, whenever the battery is removed from the device regardless of any scheduled data writes.