Alternative solid electrolytes are the next key step in advancing lithium batteries with better thermal and chemical stability. A soft solid electrolyte, (Adpn)₂LiPF₆ (Adpn, adiponitrile), is synthesized and characterized that exhibits high thermal and electrochemical stability and good ionic conductivity, overcoming several limitations of conventional organic and ceramic materials. The surface of the electrolyte possesses a liquid nano-layer of Adpn that links grains for a facile ionic conduction without high pressure/temperature treatments. Further, the material can quickly self-heal if fractured and provides liquid-like conduction paths via the grain boundaries. A substantially high ion conductivity (~10⁻⁴ S cm^–1) and lithium-ion transference number (0.54) are obtained due to weak interactions between ‘hard’ (charge dense) Li⁺ ions and the ‘soft’ (electronically polarizable) –C≡N group of Adpn. Molecular simulations predict that Li⁺ ions migrate at the co-crystal grain boundaries with a (preferentially) lower activation energy E_a and within the interstitial regions between the co-crystals with higher E_a values, where the bulk conductivity is a smaller but extant contribution. These co-crystals establish a special concept of crystal design to increase the thermal stability of LiPF₆ by separating ions in the Adpn solvent matrix, and also exhibit a unique mechanism of ion conduction via low-resistance grain boundaries, which contrasts with ceramics or gel electrolytes.

替代固体电解质是推进具有更好热稳定性和化学稳定性的锂电池的下一个关键步骤。合成并表征了一种软固体电解质 (Adpn) ₂ LiPF _{6 （Adpn，己二腈），它具有高热稳定性和电化学稳定性以及良好的离子导电性，克服了传统有机和陶瓷材料的一些局限性。}电解质的表面具有 Adpn 液体纳米层，无需高压/高温处理即可连接颗粒以实现轻松的离子传导。此外，如果材料破裂，该材料可以快速自我修复，并通过晶界提供类似液体的传导路径。相当高的离子电导率 (~10 ⁻⁴  S cm ^–1) 和锂离子迁移数 (0.54) 是由于“硬”（电荷密集）Li ⁺离子与“软”（电子可极化）–C≡N 组 Adpn 之间的弱相互作用而获得的。分子模拟预测，Li ^{+离子在具有（优先）较低活化能}E _a的共晶晶界和在具有较高E _a值的共晶之间的间隙区域内迁移，其中体积电导率较小但现存贡献。这些共晶建立了一种特殊的晶体设计概念，以提高 LiPF _{6的热稳定性}通过分离 Adpn 溶剂基质中的离子，并且还通过低电阻晶界表现出独特的离子传导机制，这与陶瓷或凝胶电解质形成对比。