A battery powered electronic device can include a wireless power system configured to receive power from a wireless power transmitter, a converter coupled to the wireless power system that converts a voltage from the wireless power system to a battery charging voltage, a battery comprising at least two cells, a power management unit that delivers power from one or more of the at least two cells to one or more subsystems of the electronic device, and a plurality of switching devices connecting the at least two cells, the converter, and the power management unit. The plurality of switching devices can be arranged so that a first switching configuration connects the cells in series for charging from the converter and a second switching configuration connects the cells in parallel for delivering power to the power management unit.