Dendrite-free Li Anode Enabled by a Metal?Organic FrameworkModified Solid Polymer Electrolyte for High-Performance Lithium Metal Batteries
writer：Wenyan Shang, Yubing Chen, Jialun Han, Ping Ouyang, Chenxin Fang, and Jie Du
keywords：solid polymer electrolyte, metal?organic framework, immobilized anion, dendrite, agglomeration, high performance
source：期刊
specific source：ACS Appl. Energy Mater. 2020, 3, 12351?12359
Issue time：2020年
Uncontrollable dendrite formation following the uneven deposition of lithium signifificantly affffects the safety and service life of lithium metal batteries (LMBs). Therefore, a metal? organic framework solid polymer electrolyte (MSPE) with immobilized anions was prepared by the copolymerization of diallyl dicarbonate and a modifified metal?organic framework material (MOFs). This not only avoids the agglomeration phenomenon caused by direct physical introduction of MOFs but also fifixes the anion (TFSI?) by the numerous coordinated unsaturated cation sites exposed on the MSPE. Based on space charge theory, anion coordination is an effffective lithium dendrite elimination method that results in protection of the lithium anode within LMBs. As a result, the assembled Li/LiFePO4 (LFP) cell exhibits a discharge specifific capacity of 154.6 mA h g?1 and a capacity retention rate of 95.75% after 200 charge?discharge cycles at 0.2 C (1 C = 180 mA h g?1) at room temperature. More importantly, the assembled Li/Li symmetric cell with an MSPE exhibits a stable and low-potential cycle for 300 h at a current density of 0.5 mA cm?2 and achieves dendrite-free lithium deposition. This study provides a promising MOF-based solid polymer electrolyte for safe and high-performance LMBs.