The urgent demand for high security and high energy density all-solid-state batteries has generated a strong interest in polyethylene oxide (PEO)-based solid polymer electrolyte (SPE). However, devising a SPE with a high ionic conductivity without sacrificing mechanical properties remains a critical challenge. Herein, an interpenetrating polymer network electrolyte is designed by chemical grafting coupling, where 2D boron nitride nanosheets and poly(ethylene glycol)diacrylate were coupled by a silane coupling agent. A considerable intensification of mechanical strength has been achieved for the SPE via the graft-coupling strategy, and the interpenetrating network with BNNs leads to the generation of amorphous regions for fast Li-ion immigration. The electrolyte integrates high mechanical strength with enhanced room-temperature ionic conductivity, enabling a long-cycle stability dendrite-free Li||Li symmetrical cell, and prominent cyclic performance is demonstrated in full cells at room temperature. Our approach provides a broader promise for the practical applications of solid-state batteries.

对高安全性和高能量密度全固态电池的迫切需求引起了人们对基于聚环氧乙烷 (PEO) 的固体聚合物电解质 (SPE) 的浓厚兴趣。然而，在不牺牲机械性能的情况下设计具有高离子电导率的 SPE 仍然是一个关键挑战。在此，通过化学接枝偶联设计了一种互穿聚合物网络电解质，其中二维氮化硼纳米片和聚（乙二醇）二丙烯酸酯通过硅烷偶联剂偶联。通过接枝耦合策略，SPE 的机械强度得到了相当大的增强，并且与 BNN 的互穿网络导致生成用于快速锂离子迁移的无定形区域。电解质结合了高机械强度和增强的室温离子电导率，实现了长循环稳定性无枝晶Li||Li对称电池，并且在室温下在全电池中表现出突出的循环性能。我们的方法为固态电池的实际应用提供了更广泛的前景。