Meng Nan, Lian Fang, Cui Guanglei
School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
Qingdao Industrial Energy Storage Research Institute, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
Small. 2021 Jan;17(3):e2005762. doi: 10.1002/smll.202005762. Epub 2020 Dec 21.
In the development of solid-state lithium batteries, solid polymer electrolyte (SPE) has drawn extensive concerns for its thermal and chemical stability, low density, and good processability. Especially SPE efficiently suppresses the formation of lithium dendrite and promotes battery safety. However, most of SPE is derived from the matrix with simple functional group, which suffers from low ionic conductivity, reduced mechanical properties after conductivity modification, bad electrochemical stability, and low lithium-ion transference number. Appling macromolecular design with multiple functional groups to polymer matrix is accepted as a strategy to solve the problems of SPE fundamentally. In this review, macromolecular design based on lithium conducting groups is summarized including copolymerization, network construction, and grafting. Meanwhile, the construction of single-ion conductor polymer is also focused herein. Moreover, synergistic effects between the designed matrix, lithium salt, and fillers are reviewed with the objective to further improve the performance of SPE. At last, future studies on macromolecular design are proposed in the development of SPE for solid-state batteries with high energy density and durability.
在固态锂电池的发展过程中，固体聚合物电解质（SPE）因其热稳定性和化学稳定性、低密度以及良好的加工性能而备受关注。特别是SPE能有效抑制锂枝晶的形成并提高电池安全性。然而，大多数SPE源自具有简单官能团的基体，存在离子电导率低、电导率改性后机械性能下降、电化学稳定性差以及锂离子迁移数低等问题。将具有多个官能团的高分子设计应用于聚合物基体被认为是从根本上解决SPE问题的一种策略。在这篇综述中，总结了基于锂导电基团的高分子设计，包括共聚、网络构建和接枝。同时，本文也聚焦于单离子导体聚合物的构建。此外，还综述了设计的基体、锂盐和填料之间的协同效应，目的是进一步提高SPE的性能。最后，针对具有高能量密度和耐久性的固态电池的SPE发展，提出了高分子设计的未来研究方向。
