Chinese Research Team Develops Novel Composite Solid-State Electrolyte, Enables 350 Stable Cycles in All-Solid-State Batteries

Researchers at the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, have made progress in developing key materials for high-energy-density all-solid-state batteries. Addressing common challenges with solid electrolytes—such as poor electrode–electrolyte interfacial contact, insufficient flexibility, low ionic conductivity, and inadequate electrochemical stability—the team proposed an inorganic-phase-induced in-situ chemical reconstruction strategy to develop a novel organic–inorganic composite solid electrolyte. This approach leverages Lewis basic active sites on the surface of lithium oxychloride (Li₃OCl) to induce an in-situ dehydrofluorination reaction of polyvinylidene fluoride (PVDF) at the interface, generating carbon–carbon double bonds. This transforms the weak organic–inorganic interface into a strongly chemically bonded one, creating a continuous lithium-ion conduction pathway with low transport energy barriers. The resulting PVDF–Li₃OCl composite solid electrolyte exhibits high ionic conductivity, excellent mechanical stability, high flexibility, superior interfacial compatibility, and single-ion conduction characteristics. An NCA-based all-solid-state battery assembled using this electrolyte and its corresponding separator demonstrated stable cycling for 350 cycles at a 1C rate, retaining 84.2% of its initial capacity. These findings have been published in the journal *Journal of Colloid and Interface Science*.