Wu Qian, Fang Mandi, Jiao Shizhe, Li Siyuan, Zhang Shichao, Shen Zeyu, Mao Shulan, Mao Jiale, Zhang Jiahui, Tan Yuanzhong, Shen Kang, Lv Jiaxing, Hu Wei, He Yi, Lu Yingying
State Key Laboratory of Chemical Engineering, Institute of Pharmaceutical Engineering, College of Chemical and Biological Engineering, Zhejiang University, 310027, Hangzhou, Zhejiang, China.
ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, 311215, Hangzhou, China.
Nat Commun. 2023 Oct 9;14(1):6296. doi: 10.1038/s41467-023-41808-3.
Solid polymer electrolytes with large-scale processability and interfacial compatibility are promising candidates for solid-state lithium metal batteries. Among various systems, poly(vinylidene fluoride)-based polymer electrolytes with residual solvent are appealing for room-temperature battery operations. However, their porous structure and limited ionic conductivity hinder practical application. Herein, we propose a phase regulation strategy to disrupt the symmetry of poly(vinylidene fluoride) chains and obtain the dense composite electrolyte through the incorporation of MoSe sheets. The electrolyte with high dielectric constant can optimize the solvation structures to achieve high ionic conductivity and low activation energy. The in-situ reactions between MoSe and Li metal generate LiSe fast conductor in solid electrolyte interphase, which improves the Coulombic efficiency and interfacial kinetics. The solid-state Li||Li cells achieve robust cycling at 1 mA cm, and the Li||LiNiCoMnO full cells show practical performance at high rate (3C), high loading (2.6 mAh cm) and in pouch cell.
具有大规模可加工性和界面相容性的固体聚合物电解质是固态锂金属电池的理想候选材料。在各种体系中，含有残留溶剂的聚偏氟乙烯基聚合物电解质对于室温电池操作具有吸引力。然而，它们的多孔结构和有限的离子电导率阻碍了实际应用。在此，我们提出一种相调控策略，以破坏聚偏氟乙烯链的对称性，并通过引入MoSe片材获得致密的复合电解质。具有高介电常数的电解质可以优化溶剂化结构，以实现高离子电导率和低活化能。MoSe与锂金属之间的原位反应在固体电解质界面中生成LiSe快导体，从而提高库仑效率和界面动力学。固态Li||Li电池在1 mA cm下实现了稳定循环，Li||LiNiCoMnO全电池在高倍率（3C）、高负载（2.6 mAh cm）和软包电池中表现出实际性能。
