BATTERY-SYSTEM CONTROL METHOD AND BATTERY SYSTEM

When a module controller of a battery system detects an abnormality of a battery module, the module controller selects the battery module without stopping the battery module. After that, the module controller compares a current value of a current supplied to a load, with a total value of rated currents of all battery modules that are normal and that are supplying power to the load. When the current value of the current supplied to the load is greater than the total value of the rated currents of the battery modules, the module controller performs a control to stop all the battery modules. When the current value of the current supplied to the load is less than or equal to the total value of the rated currents of all the battery modules that are supplying power to the load, the module controller performs a control to stop the abnormal battery module and not to stop the normal battery modules.