A battery pack having at least one electrochemical cell and a temperature dependent boost circuit is provided. Since the cell voltage is diminished at low temperatures, and as portable electronic devices typically have a minimum operational voltage limit, the boost circuit is actuated at low temperatures to step up the voltage from the cell to the electronic device. In one embodiment, the boost circuit is coupled serially between the cell and the output terminals of the battery pack. In parallel with the boost circuit is a boost bypass circuit. A controller senses the temperature of the battery pack from a temperature sensor, like a thermistor. When the temperature falls below a predetermined minimum temperature threshold, the controller actuates the boost circuit, thereby increasing the output voltage of the pack. Concurrently with the actuation of the boost circuit, the controller causes the boost bypass circuit to enter a high impedance state.