Copper sulfides and their composites for high-performance rechargeable batteries

Copper sulfides (CuxS) are widely used as the promising electrode materials for secondary batteries because of the rich abundance, low cost, excellent capacity (∼337/560 mA h/g for Cu2S/CuS) as well as favorable electrical conductivity (10−3 S/cm). Moreover, nanostructure designing and compounding with other conductive materials can enhance the electrochemical performance of CuxS. In this review, the up-to-date progress in the synthesis method as well as the application for secondary batteries (lithium-ion batteries, lithium-sulfur batteries, sodium-ion batteries, magnesium-ion batteries, and so on) of CuxS and their relevant composites have been discussed detailly. In the end, the challenges, feasible strategies, and application prospects for the CuxS are also summarized.