Drawing impedance spectroscopy for Fuel Cell by EIS

EIS (Electrochemical impedance spectroscopy) is a powerful diagnostic testing method for fuel cells because it is non-destructive and provides some useful information about fuel cell performance. This paper will design fuel cells impedance on-line testing system by electrochemical impedance spectroscopy, and draw the complex impedance spectroscopy for Fuel Cell stack. Based on fuel cells impedance on-line testing system, complex impedance data in different frequency for Fuel Cell stack is sampled and saved, by automatic frequency scanning. Firstly, accomplishing curve fitting for fuel cells impedance data by nonlinear least square, secondly, accomplishing model parameter estimation, finally, the complex impedance spectroscopy for Fuel Cell stack will be drawn. The spectroscopy can reflect fuel cells impedance variation, and lay a foundation for monitoring the health status of fuel cells and improving the working efficiency of fuel cell stacks.