Electrochemical impedance studies of capacity fading of electrodeposited ZnO conversion anodes in Li-ion battery

Abstract

Electrodeposited ZnO coatings suffer severe capacity fading when used as conversion anodes in sealed Li cells. Capacity fading is attributed to (i) the large charge transfer resistance, Rct (300-700 Ω) and (ii) the low Li+ ion diffusion coefficient, D+Li (10-15 to 10-13 cm2 s-1). The measured value of Rct is nearly 10 times higher and D+Li 10-100 times lower than the corresponding values for Cu2O, which delivers a stable reversible capacity.