Zhang Wenjie, Long Jianlin, Wang Haijun, Lan Jinle, Yu Yunhua, Yang Xiaoping
State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, North Third Ring Road 15, Chaoyang District, Beijing 100029, China.
State Key Laboratory of Fluorinated Functional Membrane Materials, Zibo 256401, China.
Molecules. 2022 Nov 3;27(21):7488. doi: 10.3390/molecules27217488.
Polymer electrolytes (PEs) with high flexibility, low cost, and excellent interface compatibility have been considered as an ideal substitute for traditional liquid electrolytes for high safety lithium metal batteries (LMBs). Nevertheless, the mechanical strength of PEs is generally poor to prevent the growth of lithium dendrites during the charge/discharge process, which seriously restricts their wide practical applications. Herein, a mechanical robust ZIF-8/epoxy composite electrolyte with unique pore structure was prepared, which effectively inhibited the growth of lithium dendrites. Meanwhile, the in situ growth of ZIF-8 in porous epoxy matrix can promote the uniform flux and fast transport of lithium ions. Ultimately, the optimal electrolyte shows high ionic conductivity (2.2 × 10 S cm), wide electrochemical window (5 V), and a large Li transference number (0.70) at room temperature. The Li||NCM811 cell using the optimal electrolyte exhibits high capacity and excellent cycling performance (83.2% capacity retention with 172.1 mA h g capacity retained after 200 cycles at 0.2 C). These results indicate that the ZIF-8/epoxy composite electrolyte is of great promise for the application in LMBs.
具有高柔韧性、低成本和优异界面兼容性的聚合物电解质（PEs）被认为是用于高安全性锂金属电池（LMBs）的传统液体电解质的理想替代品。然而，PEs的机械强度通常较差，无法在充放电过程中阻止锂枝晶的生长，这严重限制了它们的广泛实际应用。在此，制备了一种具有独特孔结构的机械坚固的ZIF-8/环氧树脂复合电解质，它有效地抑制了锂枝晶的生长。同时，ZIF-8在多孔环氧基质中的原位生长可以促进锂离子的均匀通量和快速传输。最终，最佳电解质在室温下表现出高离子电导率（2.2×10 S cm）、宽电化学窗口（5 V）和大的锂迁移数（0.70）。使用最佳电解质的Li||NCM811电池表现出高容量和优异的循环性能（在0.2 C下循环200次后容量保持率为83.2%，保留容量为172.1 mA h g）。这些结果表明，ZIF-8/环氧树脂复合电解质在LMBs应用中具有很大的前景。
