1D ZrCl4 Matrices for Enhanced Ion Transport in Glassy Chloride Electrolytes

Abstract Designing a solid‐state electrolyte (SSE) that combines the lithium‐ion transport behavior found in liquid or solid polymer electrolytes with the high lithium‐ion transference number characteristic of inorganic SSEs is an immensely appealing challenge. Herein, a cost‐effective, chain‐structured ZrCl 4 is introduced as a hosting matrix, resembling polyethylene oxide (PEO), to facilitate the dissociation of lithium salts (e.g., LiCl, Li 2 SO 4 , and Li 3 PO 4 ). The dissociated free Li‐ions can be coordinated by the [ZrCl 6 ] octahedra, forming fast ion‐conducting pathways along ZrCl 4 chains that achieve an ionic conductivity as high as 1.2 mS cm −1 . Simultaneously, ZrCl 4 serves as a Lewis acid, trapping anions and delivering a high lithium transference number approaching unit. The proposed electrolyte exhibits stable cycling performance when integrated into LiNi 0.8 Mn 0.1 Co 0.1 O 2 ||Li‐In cells. Moreover, this design strategy also extends to the synthesis of sodium‐ion conductors, achieving a high ionic conductivity of 0.3 mS cm −1 . Demonstrating a previously unreported lithium‐ion conduction mechanism, the proposed ZrCl 4 ‐based electrolytes offer a versatile approach for tailoring advanced SSEs.