Patent ID: 6369546
Filing Date: 2002-04-09
Classification: H02J

Abstract:
A distributed converter for balancing charge in a lithium-ion battery comprising:an array of cells having a predetermined number of cell units in parallel forming a cell, each of said cells has a predetermined number of cell units arranged in parallel, thereby forming said array of cells; a bulk charger for charging at least one cell in said array of cell units to a first predetermined threshold voltage; a multiplexer for measuring a voltage of each of said cells in said array of cell units; a plurality of transformer/rectifier circuits, each transformer/rectifier circuit in said plurality of transformer/rectifier circuits being associated with a respective cell in said array of cell units; a plurality of balancing switches, each equalizing switch in said plurality of balancing switches being associated with a respective transformer/rectifier circuit in said plurality of transformer/rectifier circuits; a redundant AC power supply supplying power to said plurality of transformer/rectifier circuits; and a controller for receiving measured voltages from said multiplexer and for controlling an on/off state for each of said plurality of balancing switches, whereby charging and balancing of a cell in said array of cell units occurs when a respective balancing switch is in an â€œonâ€  state until said respective cell reaches a second predetermined threshold voltage.