The influence of contact engineering on silicon‐based anode for li‐ion batteries

Abstract

Silicon is considered as the desirable anode material for lithium‐ion batteries due to its suitable discharge potential, abundant reserve, and ultra‐high specific capacity. However, poor conductivity and unstable battery performance caused by large volume change during cycling limit the further development of silicon anode. In order to avoid the unstable solid electrolyte interface layer caused by the direct contact between silicon and electrolyte, and to eliminate the structural collapse caused by the volume change during cycling, dimension size reduction, reserved voids, and novel structural framework are usually adopted. Although these methods can effectively improve the defects, a new problem is introduced and cannot be ignored: contact engineering between the coating layer and silicon core. Herein, contact engineering is classified into three categories: face to face (F2F), line to line (L2L), and point to point (P2P) according to the contact modes between the coating and core. There is utilizability of the structure categories of different contact modes and their influence on electrochemical performance. Therefore, in the future research of silicon anode, contact engineering is a non‐negligible aspect in the structural design process. Finally, feasible strategies based on contact engineering have been indicated.