A battery includes at least one battery module line, a sensor means for determining a charging stage of a battery cell, and a control unit. The battery module line includes a plurality of battery modules mounted in series, each module having at least one battery cell and a coupling unit. The at least one battery cell is mounted between a first input and a second input of the coupling unit, and the coupling unit is configured (i) to switch the at least one battery cell between a first terminal of the battery module and a second terminal of the battery module, on a first control signal, and (ii) to connect the first terminal to the second terminal on a second control signal. The sensor means is connectable to the at least one battery cell of each battery module.