Disclosed herein are a method of controlling the operation of battery modules in a battery system, which includes two or more battery modules or battery module assemblies, wherein the battery system further includes energy consuming loads for consuming charged energy, and the method includes, when a specific battery module or a specific battery module assembly is abnormally operated, connecting the abnormally operated battery module or the abnormally operated battery module assembly to the corresponding energy consuming load to forcibly discharge the charged energy, and a battery system that is capable of performing the battery system control method.