Patent ID: 7812572

Claim:
A device for charge equalizing series-connected individual cells of an energy accumulator, the device comprising: an energy accumulator including a plurality of individual cells connected in series, the energy accumulator having a connection; a DC/DC converter including an input and an output; a switch having a first switching state connecting said input of said DC/DC converter to the connection of the energy accumulator to remove energy from the energy accumulator, said switch having a second switching state connecting said input of said DC/DC converter to a further power source; a DC/AC converter connected to said output of said DC/DC converter, said DC/AC converter having an intermediate circuit capacitor and a bridge connection; AC buses disposed downstream of said DC/AC converter; a rectifier; coupling elements, a series connection of respective one of said coupling elements and said rectifier is disposed between each of the cells and a respective one of said AC buses; and selector switches, at least one of said selector switches disposed between said respective AC bus and each of the cells, the cells being electrically coupled to said respective AC bus or electrically disconnected from said respective AC bus through said selector switches.