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

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, (R_{mathrm{ct}}) (300–700 (Omega )) and (ii) the low (hbox {Li}^{+}) ion diffusion coefficient, (D_{mathrm{Li}}^{+} (10^{-15}) to (10^{-13}hbox { cm}^{2}hbox { s}^{-1})). The measured value of (R_{mathrm{ct}}) is nearly 10 times higher and (D_{mathrm{Li}}^{+}) 10–100 times lower than the corresponding values for (hbox {Cu}_{2}hbox {O}), which delivers a stable reversible capacity.