Cell coil for a lithium-ion accumulator

The invention relates to a cell coil (30, 40, 50, 60, 100, 200) for a lithium-ion battery, comprising at least two sub-cells (10, 32, 42, 44, 52, 54, 68, 70, 80, 82), which are wound in a space-saving manner and are thermally coupled to each other. According to the invention, the at least two sub-cells (10, 32, 42, 44, 52, 54, 68, 70, 80, 82) are electrically connected in parallel in normal operation, and, in the event of a fault, in particular in the event of an internal short circuit in at least one defective sub-cell (10, 32, 42, 44, 52, 54, 68, 70, 80, 82), at least one defective sub-cell (10, 32, 42, 44, 52, 54, 68, 70, 80, 82) can be electrically separated from the at least one intact sub-cell (10, 32, 42, 44, 52, 54, 68, 70, 80, 82). Because of the at least one defective sub-cell (10, 32, 42, 44, 52, 54, 68, 70, 80, 82) that can be immediately electrically separated from the intact sub-cells (10, 32, 42, 44, 52, 54, 68, 70, 80, 82) by means of an electronic monitoring device (36) in the "event of a fault", a high level of robustness of the cell coil (30, 40, 50, 60, 100, 200) in respect of internal short circuits is achieved. Among other things, the intact sub-cells (10, 32, 42, 44, 52, 54, 68, 70, 80, 82) act, because of the thermal coupling between the sub-cells (10, 32, 42, 44, 52, 54, 68, 70, 80, 82), as a damage-reducing heat sink for the waste heat that is released during the fast discharge of the affected defective sub-cell (10, 32, 42, 44, 52, 54, 68, 70, 80, 82) generally occurring in the event of a short circuit.