Multi-scale Modification Strategies and Underlying Mechanisms of Copper Current Collectors for Lithium Metal Battery Anodes

Abstract

Lithium metal serves as the core anode candidate for next-generation high-energy-density batteries. As the electronic conductive substrate and physical scaffold for lithium deposition, copper current collectors exert a decisive influence on lithium plating behaviors and battery cycle life via their interfacial properties. Commercial planar copper foils intrinsically suffer inferior lithiophilicity and insufficient interfacial stability, which readily trigger lithium dendrite proliferation and parasitic interfacial side reactions, thereby causing coulombic efficiency decay and potential safety hazards. This constitutes a critical bottleneck hindering the commercialization of lithium metal batteries. Functional modification of copper current collectors represents a vital technical route to enhance the stability of lithium metal anodes, benefiting from favorable manufacturing compatibility and low cost. From a multiscale regulation perspective, prevailing modification strategies can be categorized into three types: structural engineering, lithiophilic functionalization, and interfacial protective layer construction. This paper systematically elaborates the regulatory mechanisms, material systems, and research advances of each category, discusses standardized evaluation criteria for modification efficacy under diverse battery configurations as well as core challenges restricting industrial translation, and prospects the future development trends of this field. The presented discussions can provide theoretical guidance for the design and practical deployment of high-performance current collectors applicable to lithium metal batteries.