A battery module usable with a computer system includes a circuit to generate a power, and a controller to output the power of the circuit to an external device, for example, the computer system, and to prevent the power from being output from the circuit to the external device according to an external...http://www.google.com/patents/US8201008?utm_source=gb-gplus-sharePatent US8201008 - Battery module, computer system and power supply method thereof
