The dissociation degree of lithium electrolyte salts greatly affects the performance of solid-state polymer electrolytes (SSPE) in solid-state lithium-metal batteries (SSLBs). The previous synthetic tactics are generally based on single dissociation of electrolyte salt, for example, solely tethering the anions or capturing lithium cations. Herein, we present a dual-dissociation strategy to synthesize SSPE by simultaneously dissociate both the anions and cations among electrolyte salts. This is achieved by integrating the oligomeric silsesquioxanes (POSS) nanoparticles with suitable aperture in a poly(propylene carbonate) (PPC) gel matrix, where the POSS filler with suitable aperture interacts with both the TFSI anions and Li⁺ cations of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt. However, the Li⁺ cations are movable under an external electric field and can migrate between cathode and anode to achieve charge transportations. The room temperature ionic conductivity of SSPE filled with POSS nanoparticles was found to be superior to that of SSPE with SiO₂ fillers, with a conductivity value of 2.04 × 10⁻⁴ S cm⁻¹ and a higher Li⁺ ion transfer number of 0.71. This improvement is attributed to the utilization of a dual-dissociation strategy of lithium salt. The theoretical computations with nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS) manifest that the efficient dissociation of electrolyte salt is ascribed to the coordination effect of Li⁺ ions with four oxygen atoms among POSS cage as well as the tethering function of POSS filler for TFSI⁻ anions. This work provides an innovative dual-dissociation strategy to synthesize SSPE, which would benefit the practical use of polymer electrolytes in solid-state lithium-metal batteries.

锂电解质盐的解离度极大地影响固态锂金属电池（SSLB）中固态聚合物电解质（SSPE）的性能。以前的合成策略通常基于电解质盐的单一离解，例如仅束缚阴离子或捕获锂阳离子。在此，我们提出了一种双解离策略，通过同时解离电解质盐中的阴离子和阳离子来合成 SSPE。这是通过将具有合适孔径的低聚倍半硅氧烷 (POSS)纳米颗粒集成到聚碳酸亚丙酯 (PPC) 凝胶基质中来实现的，其中具有合适孔径的 POSS 填料与双（三氟甲磺酰基锂）的 TFSI 阴离子和 Li ⁺阳离子）酰亚胺（LiTFSI）盐。然而，Li⁺阳离子在外部电场下可移动，并且可以在阴极和阳极之间迁移以实现电荷传输。研究发现填充POSS纳米粒子的SSPE的室温^离子电导率优于填充SiO ₂，电导率为2.04×10^-4 S cm -1 ^{，Li +}更高，为0.71。这种改进归功于锂盐双解离策略的利用。核磁共振（NMR）和X射线光电子能谱（XPS）的理论计算表明，电解质盐的有效解离归因于POSS笼中Li⁺离子与四个氧原子的配位作用以及束缚功能^-的 POSS 填料。这项工作提供了一种创新的双解离策略来合成SSPE，这将有利于聚合物电解质在固态锂金属电池中的实际应用。