Patent ID: 8334673

Claim:
A voltage monitoring apparatus for monitoring an output voltage of a multiple-set battery having a plurality of unit cells which are connected in series, the voltage monitoring apparatus comprising: a plurality of voltage monitoring sections corresponding to a plurality of blocks respectively, wherein the unit cells are divided into the plurality of blocks; and a main control section which is connected to the voltage monitoring sections via a communication line, wherein each of the voltage monitoring section includes: a voltage detection section which detects voltages of the unit cells of a corresponding block; a voltage adjustment section which adjusts the voltages of the unit cells of the corresponding block so that the voltages are uniformized; an active power source which obtains power from the unit cells of the corresponding block, and supplies power to the voltage detection section and the voltage adjustment section; a power source switching section which switches a power supply mode and a power disconnect mode of the active power source; and a low consumption power source which obtains power from the unit cells of the corresponding block, and supplies power to the power source switching section; and wherein the main control section includes: a failure diagnosis section which performs a failure diagnosis of each of the voltage monitoring sections; and a switching control section which controls to disconnect a supply of the power from the active power source when a result of the failure diagnosis indicates a failure.