Patent ID: 8836291

Claim:
A battery charger comprising: a rectification processor configured to rectify an output power of a multi-phase alternate current generator and supply the output power rectified to a plurality of batteries; a charge state detector configured to determine a charge state of each of the batteries when a line-to-line voltage between two phases of a plurality of phases of the multi-phase alternate current generator is zero and thereby determine necessity of charging with respect to each of the batteries; and a charge controller configured to, when at least one of the batteries is determined to be necessary to be charged, control the rectification processor to supply the output power rectified to the at least one of the batteries in synchronization with the output timings of the multi-phase alternate current generator, thereby charging the at least one of the batteries, wherein the charge controller is configured to, when two or more of the batteries are determined to be necessary to be charged, control the rectification processor to allocate and supply the output power to the two or more of the batteries in synchronization with the output timings of the multi-phase alternative current generator, thereby charging the two or more of the batteries.