Internal Resistance and Capacitance of Microbial Fuel Cells during Startup Period

The change of internal resistance and capacitance in microbial fuel cells (MFCs) was investigated by electrochemical impedance spectrosopy (EIS), polarization slope and power density peak method during the startup period. The results showed that the total resistance and activation resistance reduced while anodic capacitance increased during the startup period of MFCs, which reflected well the reproduction and domestication of electricigens. Activation resistance, ohmic resistance and concentration resistance were able to be separated by the polarization slope method while the data were unstable. The volumetric power peak method obtained stable values of the MFCs' intermal resistance which has valuable reference for selecting external resistance in MFCs.