Impedance behavior of binderless Ni-Mo composite oxide cathode for a Li-O₂ battery via impedance spectroscopy

A lithium-air battery (Li-O₂) battery featuring a porous carbon cathode with an electrolessly deposited nickel and molybdenum oxide (Ni-Mo) composite. Cyclical charging and discharging, followed with impedance spectroscopy measurements are performed to gather frequency dependent impedance behavior. Throughout cell cycling, there is a quickly growing impedance trend and increased polarization from product buildup and surface degradation. Impedance at high frequencies is mostly capacitive but does feature some show inductive behavior from instrumentation, cathode design, or other factors typical of gas diffusion cells. Results are presented that provide insight on the reactive impedance behavior at different frequency ranges and at various cycling stages of the cell. This data gives an idea as to the state of the cathode over the course of cycling, which is supported by the images of the physical state of the fabricated cathode.