Zhang Lanshuang, Zhang Panpan, Chang Caiyun, Guo Wenbin, Guo Zi Hao, Pu Xiong
CAS Center for Excellence in Nanoscience, Beijing Key Laboratory of Micro-Nano Energy and Sensor, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 101400, China.
School of Nanoscience and Technology, University of Chinese Academy of Sciences. Beijing 100049, China.
ACS Appl Mater Interfaces. 2021 Oct 6;13(39):46794-46802. doi: 10.1021/acsami.1c14462. Epub 2021 Sep 21.
Poor room-temperature ionic conductivities and narrow electrochemical stable windows severely hinder the application of conventional poly(ethylene oxide)-based (PEO-based) solid polymer electrolytes (SPEs) for high-energy-density lithium metal batteries (LMBs). Herein, we designed and synthesized a PEO-based self-healing solid polymer electrolyte (SHSPE) via dynamically cross-linked imine bonds for safe, flexible solid LMBs. The constructed dynamic networks endow this SPE with fascinating intrinsic self-healing ability and excellent mechanical properties (extensibility > 500% and stress >130 kPa). More importantly, this SHSPE exhibits ultrahigh ionic conductivity (7.48 × 10 S cm at 25 °C) and wide ESW (5.0 V vs Li/Li). As a result, Li||Li symmetrical cells with the SHSPE showed reliable stability in a >1200 h cycling test under room temperature. The assembled Li|SHSPE|LiFePO cell maintained a discharge capacity of 126.4 mAh g after 300 cycles (0.1C, 27 °C). This work highlights a promising strategy for next-generation room-temperature solid-state LMBs.
室温离子电导率低和电化学稳定窗口窄严重阻碍了传统聚环氧乙烷基（PEO基）固体聚合物电解质（SPEs）在高能量密度锂金属电池（LMBs）中的应用。在此，我们通过动态交联亚胺键设计并合成了一种用于安全、柔性固态LMBs的PEO基自愈合固体聚合物电解质（SHSPE）。构建的动态网络赋予该SPE迷人的固有自愈合能力和优异的机械性能（伸长率>500%，应力>130 kPa）。更重要的是，这种SHSPE表现出超高的离子电导率（25°C时为7.48×10 S cm）和宽的电化学稳定窗口（相对于Li/Li为5.0 V）。因此，具有SHSPE的Li||Li对称电池在室温下超过1200小时的循环测试中显示出可靠的稳定性。组装的Li|SHSPE|LiFePO电池在300次循环（0.1C，27°C）后保持126.4 mAh g的放电容量。这项工作突出了一种用于下一代室温固态LMBs的有前景的策略。
