Aligned copper zinc tin sulfide nanorods as lithium-ion battery anodes with high specific capacities

Highly aligned copper zinc tin sulfide nanorods electrophoretically deposited directly on the current collector are tested for suitability as Li-ion battery anodes in both half-cell (HC) and full-cell (FC) configurations. This facile fabrication process offers several advantages for high-performance nanostructured battery electrodes, notably the formation of a dense, conductive carbon and binder-free film maximizing active material content. High initial capacities of 1611 and 1369 mA h g–1 are achieved for the HC and FC, respectively. The capacity trends and degradation mechanisms for this combined alloying and conversion material are analyzed in detail using differential capacity plots and electrochemical impedance spectroscopy, and it is determined that an evolution in the electrode resistance (instead of typical material pulverization/delamination) is the major driver of an initial capacity fade followed by a dramatic capacity recovery. Differences in capacity retention trends between HCs and FCs are highlighted, emphasizing the importance of extended testing in commercial style setups for complete material evaluation.