Solid-state electrolytes (SSEs) have emerged as high-priority materials for safe, energy-dense and reversible storage of electrochemical energy in batteries. In this Review, we assess recent progress in the design, synthesis and analysis of SSEs, and identify key failure modes, performance limitations and design concepts for creating SSEs to meet requirements for practical applications. We provide an overview of the development and characteristics of SSEs, followed by analysis of ion transport in the bulk and at interfaces based on different single-valent (Li⁺, Na⁺, K⁺) and multivalent (Mg²⁺, Zn²⁺, Ca²⁺, Al³⁺) cation carriers of contemporary interest. We analyse the progress in overcoming issues associated with the poor ionic conductivity and high interfacial resistance of inorganic SSEs and the poor oxidative stability and cation transference numbers of polymer SSEs. Perspectives are provided on the design requirements for future generations of SSEs, with a focus on the chemical, geometric, mechanical, electrochemical and interfacial transport features required to accelerate progress towards practical solid-state batteries in which metals are paired with energetic cathode chemistries, including Ni-rich and Li-rich intercalating materials, sustainable organic materials, S₈, O₂ and CO₂.

固态电解质（SSE）已作为高优先级材料出现，用于安全，能量密集和可逆地存储电池中的电化学能量。在这篇评论中，我们评估了SSE的设计，综合和分析的最新进展，并确定了关键的故障模式，性能限制和设计概念，以创建SSE以满足实际应用的要求。我们概述了SSE的发展和特征，然后分析了基于不同单价（Li ⁺，Na ⁺，K ⁺）和多价（Mg 2 ⁺，Zn ²⁺，Ca 2 ⁺，Al ³⁺）具有当代意义的阳离子载体。我们分析了克服与无机SSE的差离子电导率和高界面电阻以及聚合物SSE的差的氧化稳定性和阳离子转移数有关的问题的进展。提供了有关下一代SSE的设计要求的观点，重点关注了化学，几何，机械，电化学和界面传输特性，这些特性加快了向金属与高能阴极化学配对的实用固态电池的发展，包括富镍和富锂的插层材料，可持续的有机材料，S ₈，O ₂和CO ₂。