Low frequency inductive loop in EIS measurements of an open-cathode polymer electrolyte fuel cell stack. Impedance of water vapour diffusion in the cathode catalyst layer

On the Role of Inductive Loops at Low Frequencies in Pem Electrolysis

“…Another explanation is that the measured series resistance is too high due to the fact that there are slow processes decreasing the membrane resistivity, which are only recognizable at low frequencies. Examples of this are different states of humidification due to slow water transport and changes in catalyst coverage as suggested for PEMFCs [15,17,35].…”

“…These are the formation of platinum oxide at the surface and its dissolution [15], side reactions including adsorbed intermediates (e.g. hydrogen peroxide) [16] or slow water diffusion in the ionomer [15,17]. Most reports describe this inductive behavior using physicochemical models, equivalent circuit models (ECM) or Distribution of Relaxation Time (DRT) analysis [13,15,16,18,19].…”

A theory of inductive loops in electrochemical impedance spectroscopy

“…The experimentally observed arcs in a Nyquist plot of the impedance with positive imaginary part in the low frequency part of the spectrum received the unfortunate moniker of an "inductive loop" [12,8,23,21,10]. It is generally agreed that magnetic effects play no significant role in the functioning of most electrochemical systems and devices, and even when they do, the inductive effects manifest themselves at the high end of the frequency spectrum [7,16,6].…”