Influences of Separator Thickness and Surface Coating on Lithium Dendrite Growth: A Phase-Field Study
Yajie Li,
Liting Sha,
Peili Lv,
Na Qiu,
Wei Zhao,
Bin Chen,
Pu Hu,
Geng Zhang
Affiliations
Yajie Li
School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
Liting Sha
School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
Peili Lv
Tencent Inc., Shanghai 200233, China
Na Qiu
Mechanical and Electrical Engineering College, Hainan University, Haikou 570228, China
Wei Zhao
School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
Bin Chen
School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
Pu Hu
Hubei Key Laboratory of Plasma Chemistry and Advanced Materials, School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan 430205, China
Geng Zhang
Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
Li dendrite growth, which causes potential internal short circuit and reduces battery cycle life, is the main hazard to lithium metal batteries. Separators have the potential to suppress dendrite growth by regulating Li+ distribution without increasing battery weight significantly. However, the underlying mechanism is still not fully understood. In this paper, we apply an electrochemical phase-field model to investigate the influences of separator thickness and surface coating on dendrite growth. It is found that dendrite growth under thicker separators is relatively uniform and the average dendrite length is shorter since the ion concentration within thicker separators is more uniform. Moreover, compared to single layer separators, the electrodeposition morphology under particle-coated separators is smoother since the particles can effectively regulate Li ionic flux and homogenize Li deposition. This study provides significant guidance for designing separators that inhibit dendrites effectively.
