Preparation of the Porous Copper Foil Current Collector for High-Performance Lithium-Ion Batteries by Electro-Codeposition: Effect of Stirring Speed

Abstract

As an indispensable component of lithium-ion batteries (LIBs), the application of porous copper (Cu) foil current collector is an effective method to improve the performance and energy density of LIBs. In this work, a porous Cu (PCu) foil was fabricated by acid washing the Cu-Fe3O4 foil prepared by the electro-codeposition in a stirred CuSO4 solution containing the magnetic Fe3O4 nanoparticles. The effect of the stirring speed on the properties of PCu foils and the battery performance of PCu foil as current collectors were investigated. The surface roughness of the PCu foil increases, while its volume density decreases as the stirring speed rises. The volume density of PCu foil (6.63 g cm−3) prepared at 400 rpm (PCu400) is reduced by 22.4% than that of the commercial Cu foil (8.55 g cm−3). The specific capacity (241.2 mAh g−1) of the cell with PCu400 current collector is 31.3% higher than that of the cell with commercial Cu current collector (183.7 mAh g−1) after 300 charge-discharge cycles at 2 C. The electro-codeposition of porous Cu foil current collectors offers a promising method for high-performance lightweight LIBs.