Solid-state lithium batteries (SSLBs) are promising next-generation energy storage devices due to their potential for high energy density and improved safety. The properties and physical parameters of the solid-state electrolyte (SSE), as a critical component of the battery, have a significant effect on the electrochemical performance and energy density. In recent years, thick SSEs have been widely used in SSLBs but present several drawbacks in terms of increased internal resistance, additional inactive material content, low practical energy densities, and higher battery manufacturing costs. Reducing the thickness of SSEs and developing high-performance thin SSE-based SSLBs are essential for the commercialization of SSLBs. In this review, we comprehensively summarize the fabrication methods of thin SSEs, their rational design, and their manufacturing processes and applications in different SSLB systems. Moreover, advanced characterization techniques for understanding the Li⁺ transport kinetics and structural evolution of SSEs at the interface are introduced. Additionally, the gravimetric/volumetric energy densities for various SSLB pouch cells with SSEs less than 100 μm thick are evaluated. Lastly, other cell design parameters are tuned to achieve gravimetric/volumetric energy densities over 300 W h kg⁻¹/500 W h L⁻¹, and the future directions of thin SSEs in SSLBs are speculated upon.

中文翻译：

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用于高能量密度固态锂电池的薄电解质的最新进展和观点

固态锂电池（SSLB）由于具有高能量密度和提高安全性的潜力，因此有望成为下一代储能设备。作为电池的关键组件的固态电解质（SSE）的特性和物理参数对电化学性能和能量密度具有重要影响。近年来，厚的SSE已广泛用于SSLB中，但在内部电阻增加，附加的非活性材料含量，较低的实际能量密度和较高的电池制造成本方面存在一些缺点。减少SSE的厚度并开发高性能的基于SSE的薄SSLB对于SSLB的商业化至关重要。在这篇综述中，我们全面总结了薄SSE的制造方法，合理的设计，及其在不同SSLB系统中的制造过程和应用。此外，先进的表征技术可用于了解锂离子⁺介绍了界面上SSE的传输动力学和结构演化。此外，评估了SSE厚度小于100μm的各种SSLB袋式电池的重量/体积能量密度。最后，调整其他电池设计参数以实现重量/体积能量密度超过300 W h kg ^-1 / 500 W h L ^-1，并推测SSLB中薄SSE的未来方向。