3D Cu3N nanowire/Cu foam composite host enables high-capacity and long-storage lithium battery

Abstract

Lithium batteries are widely used in electronic and medical devices for the advantages of high energy/power densities and low self-discharge. However, the active lithium metal anode can react with electrolyte to form unstable solid electrolyte interface (SEI) and affect the rate performance and stability of lithium batteries. In this work, we design a 3D Cu foam (CF) based copper nitride nanowire (Cu3N NW) array, and further construct stable 3D composite Li anode by molten lithium metal infusion method. Cu3N NWs can improve the lithiophilicity and ionic conductivity, and provide high specific surface area, uniform local current density and abundant diffusion channels for lithium-ion flux. The designed 3D Cu3N NW/Cu foam electrode achieves uniform lithium deposition, excellent discharge performance and stability under high temperature and long-term storage conditions. The Li@Cu3N NW/CF-CFx battery exhibits excellent discharge specific capacity of 1080 mAh g-1 (0.1 C) and remarkable rate capacity of 546 mAh g-1 (8 C). After 60 days of storage at room temperature and 55 °C, the battery also demonstrates excellent storage performance of 874 and 627 mAh g-1. This work provides a facile and effective strategy for designing stable composite Li anode with a Li3N-rich SEI for high-performance lithium batteries.