The invention is directed to a battery system. The battery system includes a plurality of battery cell units, one or more switching assemblies operatively configured to selectively electrically connect any one of the battery cell units from the plurality of battery cell units in series with any other battery cell unit from the plurality of battery cell units, and disconnect any one of the battery cell units from being connected with any other battery cell units from the plurality of battery cell units, wherein the switching assemblies are configured to selectively connect and disconnect the battery cell units based on a set of control parameters. The battery system further includes two or more controllers for determining the set of control parameters and controlling the switching assemblies so as to provide a system output having a controllable voltage profile. The two or more controllers are configured for synchronised operation.