Coordination‐Constrained Zinc Ions Transport in Solid‐State Electrolytes: Mechanisms and Design Principles

ABSTRACT

Zinc‐ion batteries (ZIBs) are regarded as potential candidates for next‐generation energy storage systems due to their intrinsic safety, low cost, and environmental sustainability. Solid‐state electrolytes hold potential for effectively addressing issues in aqueous electrolytes. However, the development of solid‐state ZIBs is fundamentally limited by the physicochemical characteristics of Zn ²⁺ . Due to the multivalent nature of Zn ²⁺ , they are subject to stronger coordination constraints, and Zn ²⁺ migration is dominated by desolvation processes and coordination restructuring, contributing to slow ion transport in solid‐state environments. Here, we establish a mechanism‐oriented framework for understanding Zn ²⁺ transport in solid‐state electrolytes, including inorganic solid‐state electrolytes, solid‐state polymer electrolytes, and quasi‐solid‐state electrolytes. Specifically, we summarize the vacancy transport mechanism and gap transport mechanism for Zn ²⁺ transport in inorganic solid‐state electrolytes, the chain segment motion‐assisted transport mechanism in solid‐state polymer electrolytes, and the liquid–solid synergistic mechanism in quasi‐solid‐state electrolytes. On this basis, we propose general design principles for overcoming coordination constraints in each type of solid‐state electrolyte. Importantly, the concepts presented here extend beyond zinc‐ion systems and offer a unified perspective on multivalent‐ion transport in solid‐state electrolytes. This work will provide actionable insights for the rational design of next‐generation solid‐state batteries.