Solid-state Li-ion batteries (SSBs) have been regarded as the most promising systems to power electronic devices and electric vehicles because of their high energy density and safety. As the key component of SSBs, solid electrolytes have a substantial influence on battery performance. In recent years, polymeric composite electrolytes (PCEs) that combine polymer electrolytes with various fillers have attracted tremendous attention as a result of their high mechanical flexibility, high interfacial compatibility with electrodes, and easy processability. In this review, we provide a comprehensive summary of the recent progress in filler engineering of polymer electrolytes for SSBs. First, the challenges facing PCEs associated with the physical and chemical strategies for dispersing fillers are discussed. Then, the latest research papers regarding various fillers used in PCEs are classified and reviewed in detail. Moreover, their effects on physical and electrochemical properties, interfacial stability, and Li⁺-migration mechanisms are discussed, with the aim of improving the understanding of filler-reinforced PCEs for the development of SSBs.

中文翻译：

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固态锂离子电池聚合物电解质填充工程的最新进展：综述

固态锂离子电池（SSB）具有高能量密度和安全性，因此被认为是为电子设备和电动汽车供电的最有希望的系统。作为SSB的关键成分，固体电解质对电池性能有很大影响。近年来，由于高分子电解质的高机械柔韧性，与电极的高界面相容性和易加工性，将高分子电解质与各种填料结合在一起的高分子复合电解质（PCE）引起了极大的关注。在这篇综述中，我们提供了用于SSB的聚合物电解质填料工程的最新进展的全面摘要。首先，讨论了与分散填料的物理和化学策略相关的PCE面临的挑战。然后，有关PCE中使用的各种填料的最新研究论文已进行分类和详细审查。此外，它们对物理和电化学性质，界面稳定性和锂的影响讨论了⁺迁移机制，目的是增进对填充增强PCE的了解，以开发SSB。