The invention relates to a controllable energy store (2) with n parallel energy supply branches (3-1, 3-2, 3-3), wherein n≧1, each said branch having a first energy supply sub-branch (3-11; 3-21; 3-31) and a second energy supply sub-branch (3-12; 3-22; 3-32) that is connected in parallel to said first energy supply sub-branch. Each energy supply sub-branch (3-11; 3-12; 3-21; 3-22; 3-31; 3-32) has at least one energy storing module (4), each of which comprises at least one electric energy storing cell (5) with a corresponding controllable coupling unit (6). The coupling units (6) disconnect the energy supply sub-branch (3-11; 3-12; 3-21; 3-22; 3-31; 3-32) or bridge the respective corresponding energy storing cells (5) or connect the respective corresponding energy storing cells (5) into the respective energy supply sub-branch (3-11; 3-12; 3-21; 3-22; 3-31; 3-32) dependent on control signals. The energy storing cells (5) of the energy storing modules (4) in the first energy supply sub-branch (3-11; 3-21; 3-31) and the energy storing cells (5) of the energy storing modules (4) in the second energy supply sub-branch (3-12; 3-22; 3-32) are arranged in an anti-parallel manner.