Patent ID: 6394207
Filing Date: 2002-05-28
Classification: B60L,H01M,Y02E,Y02T

Abstract:
In a fuel-cell-powered vehicle having a fuel cell system for generating electricity from hydrogen and oxygen, a traction motor energized by said electricity for propelling said vehicle, power electronics for controlling said traction motor, a heat exchanger for controlling the environment in an occupant compartment of the vehicle, and a radiator for expelling excess heat from said vehicle, the improvement comprising: a high temperature heat transfer circuit including a heat-generating fuel processor for converting a liquid hydrocarbon into hydrogen for fueling a PEM fuel cell, at least one endothermic device extracting heat from said high temperature circuit, and a first pump for circulating a dielectric liquid heat transfer medium through said high temperature circuit; a low temperature heat transfer circuit including said fuel cell, said traction motor, said electronics, said radiator, and a second pump for circulating said heat transfer medium through said low temperature circuit; a first valve communicating said high and low temperature circuits and adapted, when open, to direct a first quantity of said medium from one of said circuits into the other of said circuits; a second valve communicating said high and low temperature circuits and adapted to direct a second quantity of said medium equal to said first quantity from said other circuit into said one circuit when said first valve is open; and a controller responsive to the thermal requirements of said vehicle for controlling the opening and closing of said first valve to change the temperature of the medium in each circuit.