Patent ID: 8766602
Filing Date: 2014-07-01
Classification: H01M,H02H,H02J,Y02E

Abstract:
1. A pre-charge circuit, comprising: first and second power supply terminals for coupling a power supply; first and second load terminals for coupling a plurality of battery cells to be charged; a first current path for coupling the first of the supply terminals to the first of the load terminals; a second current path for coupling the second of the supply terminals to the second of the load terminals; a third current path for coupling the first of the supply terminals to the first of the load terminals; and a plurality of switching elements for selective opening and closing each of the first, second, and third current paths; and a control element for controlling the plurality of switching elements, wherein the third current path comprises at least one pre-charge resistor in series with a positive temperature coefficient (PTC) resistor, and wherein a transition temperature of the PTC resistor is configured to correlate with a first current through the PTC resistor that is lower than a second current required for adversely affecting the pre-charge resistor, and wherein the precharge resistor is rated for handling a pre-defined pre-charge pulse.