Patent ID: 6519539
Filing Date: 2003-02-11
Classification: G01R,H01M,Y02E

Abstract:
An apparatus for determining at least the real component of a fuel cell's complex impedance, the apparatus comprising, a load device, connectable to the fuel cell for drawing a current from the fuel cell; a voltage sensing circuit connectable across the fuel cell for in use sensing direct and alternating components of a voltage across the fuel cell; a current sensing circuit, for in use sensing direct and alternating components of a current drawn from the fuel cell by the load device, wherein the load device is configured to draw a direct current with a superimposed alternating current signal; and an analysis device, connected to the voltage sensing circuit and the current sensing circuit for analyzing the detected direct and alternating components of the voltage and the detected direct and alternating components of the current to determine real and imaginary parts of the fuel cell impedance at different frequencies, whereby the real part of the fuel cell impedance can be determined.