Competitive Roles of Conductivity and Lithiophility in Composite Lithium Metal Anode
Wenbo Tang, Nailu Shen, Xiaosong Xiong, He Liu, Xin Sun, Jiaxin Guo, Feng Jiang, Tao Wang, Yuan Ma, Yiren Zhong, Jiarui He, Zhigang Zhu, Long Kong, Gulnur Kalimuldina, Xin‐Bing Cheng, Yuping Wu
Abstract
For the three-dimensional conductive host, the uneven lithium deposition and the dependence on the pore structure and lithiophility are a great challenge for lithium metal anodes. Herein, we employed facial chemical etching techniques on brass foil to fabricate three-dimensional copper hosts with diverse pore structures and lithiophilities, thus intending to understand the lithium depositing mechanisms in porous hosts. The copper host with a more pronounced pore structure exhibits the lower polarization voltage induced by its large specific surface area, which reduces the local current density and provides a great deal of pathway for lithium ion diffusion. Meanwhile, it exhibits high nucleation overpotential and a short lifespan due to a reduced number of favorable lithium nucleation sites caused by the reduced lithiophilic zinc sites and a marked increase in the routes between nucleation sites. Therefore, the appropriate pore structure needs a consideration of efficient balance between the nucleation overpotential, the polarization voltage, and Coulombic efficiency. This insight underscores the pivotal role of well-suited pore structures in three-dimensional hosts, providing profound guidance for the efficient design of advanced host for lithium metal anode.