Patent ID: 6538414
Filing Date: 2003-03-25
Classification: H02J

Abstract:
An energy storage device comprising a unit energy storage device having a plurality of capacitor cells or secondary battery cells connected in series to each other; and a cell energy adjusting device which transfers energy charged in one cell selected from said plurality of cells to input/output terminals of said unit energy storage device from the selected one cell, said cell energy adjusting device comprising:a transformer having a plurality of primary coils and a secondary coil electrically insulated and mutually coupled magnetically; a switching circuit which opens and closes a connection circuit connecting between said selected one cell and one coil among said plurality of primary coils; a circuit connecting the secondary coil of said transformer to the input/output terminals of said unit energy storage device through a rectifying circuit; and, a control circuit which, by driving said switching circuit, adjusts the energy amount stored in said selected one cell to a specific ratio with respect to the overall energy amount stored by said unit energy storage device.