Method for charging an energy store with at least one cell block comprising multiple series-connected battery cells by means of a series charging current I 0 flowing through all battery cells, wherein at least some of the battery cells can have different capacitances C N, with the characteristics: a) at predefined time intervals, the capacitances C N of the individual battery cells are measured and stored in a memory of a monitoring and control device; b) taking into consideration a predefined C-factor, which corresponds to the quotient of maximum charging current I N;max to capacity C N, the maximum charging currents I N;max that are characteristic of the individual capacitances C N are then determined by the monitoring and control device; c) then, during a predefined time t ≤ 1/C-factor, the battery cells are charged simultaneously at the maximum charging currents I N;max assigned to these battery cells, wherein - the battery cells with a maximum charging current I N;max that corresponds to the series charging current I 0 are charged only by the series charging current I 0, - the battery cells with a maximum charging current I N;max that is greater than the series charging current I 0 are simultaneously charged by the series charging current I 0 and by auxiliary charging currents I N that can be removed from the cell block via auxiliary charging/discharging devices, for which: I N =I N;max -I 0, and - the battery cells with a maximum charging current I N;max that is lower than the series charging current I 0 are charged by the series charging current I 0, wherein the currents that exceed the maximum charging currents I N;max: I 0 -I N;max are simultaneously supplied to the cell block as auxiliary discharging currents via corresponding auxiliary charging/discharging devices, or, if the calculated maximum charging currents I N;max are all greater than the available series charging current I 0, simultaneously at charging currents with values that are in the same ratio to one another as the calculated maximum charging currents I N;max. a) at predefined time intervals, the capacitances C N of the individual battery cells are measured and stored in a memory of a monitoring and control device; b) taking into consideration a predefined C-factor, which corresponds to the quotient of maximum charging current I N;max to capacity C N, the maximum charging currents I N;max that are characteristic of the individual capacitances C N are then determined by the monitoring and control device; c) then, during a predefined time t ≤ 1/C-factor, the battery cells are charged simultaneously at the maximum charging currents I N;max assigned to these battery cells, wherein - the battery cells with a maximum charging current I N;max that corresponds to the series charging current I 0 are charged only by the series charging current I 0, - the battery cells with a maximum charging current I N;max that is greater than the series charging current I 0 are simultaneously charged by the series charging current I 0 and by auxiliary charging currents I N that can be removed from the cell block via auxiliary charging/discharging devices, for which: I N =I N;max -I 0, and - the battery cells with a maximum charging current I N;max that is lower than the series charging current I 0 are charged by the series charging current I 0, wherein the currents that exceed the maximum charging currents I N;max: I 0 -I N;max are simultaneously supplied to the cell block as auxiliary discharging currents via corresponding auxiliary charging/discharging devices, - the battery cells with a maximum charging current I N;max that corresponds to the series charging current I 0 are charged only by the series charging current I 0, - the battery cells with a maximum charging current I N;max that is greater than the series charging current I 0 are simultaneously charged by the series charging current I 0 and by auxiliary charging currents I N that can be removed from the cell block via auxiliary charging/discharging devices, for which: I N =I N;max -I 0, and - the battery cells with a maximum charging current I N;max that is lower than the series charging current I 0 are charged by the series charging current I 0, wherein the currents that exceed the maximum charging currents I N;max: I 0 -I N;max are simultaneously supplied to the cell block as auxiliary discharging currents via corresponding auxiliary charging/discharging devices,