Application of Multi Parameter Fitting in Electrochemical Impedance Spectroscopy Fitting Using Gnuplot

The fitting of electrochemical impedance spectroscopy is an important part of battery performance testing,the ideal results can be acquired only by tried to fit many times. Multi parameter data fitting using open source software Gnuplot was studied and fitting curves were plotted. The result shows that Gnuplot can handle complex fitting problem easily,and it is insensitivity to the initial guess value in processing multi parameter fitting,the fitting results is accurate and reliable.