Cation-polymerized artificial SEI layer modified Li metal applied in soft-matter polymer electrolyte

Siming Tang; Qingyang Mei; Yutong Zhai; Yulong Liu

doi:10.1088/1361-6528/ad49ad

Cation-polymerized artificial SEI layer modified Li metal applied in soft-matter polymer electrolyte

Nanotechnology. 2024 May 10. doi: 10.1088/1361-6528/ad49ad. Online ahead of print.

Authors

Siming Tang¹, Qingyang Mei¹, Yutong Zhai¹, Yulong Liu²

Affiliations

¹ Northeast Normal University, Renming ST., Changchun, Jilin, 130024, CHINA.
² Northeast Normal University, Renming Street, Changchun, Jilin, Changchun, 130024, CHINA.

PMID: 38729124
DOI: 10.1088/1361-6528/ad49ad

Abstract

Li metal batteries with polymer electrolyte are of great interest for next-generation batteries for high safety and high energy density. However, uneven deposition on the lithium metal surface can greatly affect battery life. Therefore, surface modification on the Li metal become necessary to achieve good performance. Herein, an artificial solid electrolyte interface (SEI) modified lithium metal anode is prepared using cation-polymerization process, as triggered by PF5 generated from CsPF6. As a result, the polarization voltage of Li||Li symmetric battery assembled with artificial SEI-modified Li metal anode was stable with a small over-potential of 25 mV after 3000 h at current density of 1.5 mA cm-2. Electrochemical performance of Li||NCM 622 (LiNi0.6Co0.2Mn0.2O2) full cell with soft-matter polymer electrolyte is significantly improved than bare Li-metal, the capacity retention is 75% after 120 cycles with N/P=3:1 at a cut-off voltage of 4.3 V. Our work has shed lights on the commercialization of Li metal battery with polymer electrolyte.

Keywords: Li metal battery; NCM 622; SEI; polymer electrolyte.