Abstract: An electrical energy storage device includes prismatic energy storage cells arranged adjacent to one another such that interfaces of adjacent storage cells run at a distance from one another such that the interfaces of the adjacent storage cells form an intermediate space. A respective first layer is arranged between the interfaces of adjacent storage cells, the first layer abutting one of the two interfaces of the adjacent storage cells under pressure. Either the respective first layer also abuts the second of the two interfaces of the adjacent storage cells under pressure, or a second layer is arranged between the interfaces of adjacent storage cells, the second layer abutting the second of the two interfaces of the adjacent storage cells under pressure. A heat-conducting device is arranged in or between the first layer and the second layer is conducted out of the intermediate space between the adjacent storage cells.

Abstract: In a method for balancing an energy storage system, a capacitance of capacitive storage modules of a series circuit of capacitive storage modules is determined. The capacitive storage modules are connected to a balancing device to allow control of a charge of each of the capacitive storage modules via a flow of current between the balancing device and the capacitive storage modules. For each of the capacitive storage modules a module charge is determined from a voltage of the capacitive storage module and a predefined balancing voltage. A reference charge is determined from the module charges of the capacitive storage modules, and a balancing charge is determined for each of the capacitive storage modules from the reference charge and the module charge of the capacitive storage module. The charge of the capacitive storage modules is controlled by exchanging the balancing charge between the capacitive storage module and the balancing device.

Abstract: An electrical energy storage device includes prismatic energy storage cells arranged adjacent to one another such that interfaces of adjacent storage cells run at a distance from one another such that the interfaces of the adjacent storage cells form an intermediate space. A respective first layer is arranged between the interfaces of adjacent storage cells, the first layer abutting one of the two interfaces of the adjacent storage cells under pressure. Either the respective first layer also abuts the second of the two interfaces of the adjacent storage cells under pressure, or a second layer is arranged between the interfaces of adjacent storage cells, the second layer abutting the second of the two interfaces of the adjacent storage cells under pressure. A heat-conducting device is arranged in or between the first layer and the second layer is conducted out of the intermediate space between the adjacent storage cells.

Abstract: In a method for balancing an energy storage system, a capacitance of capacitive storage modules of a series circuit of capacitive storage modules is determined. The capacitive storage modules are connected to a balancing device to allow control of a charge of each of the capacitive storage modules via a flow of current between the balancing device and the capacitive storage modules. For each of the capacitive storage modules a module charge is determined from a voltage of the capacitive storage module and a predefined balancing voltage. A reference charge is determined from the module charges of the capacitive storage modules, and a balancing charge is determined for each of the capacitive storage modules from the reference charge and the module charge of the capacitive storage module. The charge of the capacitive storage modules is controlled by exchanging the balancing charge between the capacitive storage module and the balancing device.