Copper current collector: The cornerstones of practical lithium metal and anode-free batteries

Comparing with the commercial Li-ion batteries, Li metal secondary batteries (LMB) exhibit unparalleled energy density. However, many issues have hindered the practical application. As an element in lithium metal and anode-free batteries, the role of current collector is critical. Comparing with the cathode current collector, more requirements have been imposed on anode current collector as the anode side is usually the starting point of thermal runaway and many other risks, additionally, the anode in Li metal battery very likely determines the cycling life of full cell. In the review, we first give a systematic introduction of copper current collector and the related issues and challenges, and then we summarize the main approaches that have been mentioned in the research, including Cu current collector with 3D architecture, lithophilic modification of the current collector, artificial SEI layer construction on Cu current collector and carbon or polymer decoration of Cu current collector. Finally, we give a prospective comment of the future development in this field. Constructing suitable copper anode current collector can tackle the problems of lithium metal anode, especially for anode free systems. In this review, first copper current collector and the related issues are systematically introduced, then main approaches conducted on copper current collector modification in previous researches are summarized, and in the end, some concerns about the current technology and future development of copper current collector are made. image