Patent ID: 8486548

Claim:
A battery storage system, comprising: a plurality of battery modules that are electrically connected in series and in parallel, each comprising a plurality of battery cells; a plurality of sensors provided to each of the plurality of battery modules, that output at least signals corresponding to voltage and current of the each of the battery modules; a plurality of first control devices each of which is provided to the each of the plurality of battery modules, and obtains a power that can be inputted and outputted to and from the each of the battery modules based upon the voltage and current obtained from the output signals of the sensors of the each of the battery modules; and a second control device that is separate from the first control devices and performs overall control of the plurality of first control devices, wherein the second control device is arranged independently of the battery modules and provided for all of the battery modules, and the second control device is programmed to calculate, when a fault of a sensor in any one of the plurality of battery modules has occurred, a total power that can be inputted and outputted to and from the all of the battery modules, based upon powers each of which can be inputted and outputted to and from each of other battery modules than a battery module in which the sensor has detected the fault, and outputs information of the total power.