中国科技大学陈立峰团队报道了，室温下柔性全固态锂金属电池聚合物电解质的光激发增强高离子电导率。相关研究成果于2024年10月29日发表在《德国应用化学》。

设计用于室温使用的具有高离子电导率的固体聚合物电解质（SPEs），对于推进柔性全固态储能装置至关重要。迫切需要创新战略来开发安全、稳定和高性能的SPEs。

该文中，研究人员在光催化设计原理的指导下，将光激发调制的异质结引入SPEs中作为催化活性填料，并使用天然细菌纤维素来提高无机填充SPE的机械性能。

原位光热实验和理论计算表明，在光激发下，聚环氧乙烷电解质中痕量异质结产生的强光生电场显著增强了锂盐的离解，增加了可移动Li⁺的浓度。这导致离子电导率大幅增加，在25°C时达到0.135 mS cm^-1，Li⁺转移数高达0.46。

柔性全固态锂金属袋电池即使在反复弯曲和折叠后，表现出178.8 mAh g^-1的惊人放电容量，并表现出卓越的长期循环稳定性，在1C（25°C）下250次循环后仍保持其初始容量的86.7%。

该项研究为开发高性能柔性锂金属电池提供了一种新方法。

附：英文原文

Title: Photoexcitation-Enhanced High-Ionic Conductivity in Polymer Electrolytes for Flexible, All-Solid-State Lithium-Metal Batteries Operating at Room Temperature

Author: Rong-Hao Wang, Weiyi Wang, Yu-Zhen Zhang, Wei Hu, Liang Yue, Jia-Hao Ni, Wan-Qun Zhang, Gang Pei, Shangfeng Yang, Li-Feng Chen

Issue&Volume: 2024-10-29

Abstract: Designing solid polymer electrolytes (SPEs) with high ionic conductivity for room-temperature operation is essential for advancing flexible all-solid-state energy storage devices. Innovative strategies are urgently required to develop SPEs that are safe, stable, and high-performing. In this work, we introduce photoexcitation-modulated heterojunctions as catalytically active fillers within SPEs, guided by photocatalytic design principles, and employ natural bacterial cellulose to enhance the mechanical properties of the inorganic-filled SPEs. In-situ photothermal experiments and theoretical calculations reveal that the strong photogenerated electric field produced by trace heterojunctions within poly(ethylene oxide) electrolytes under photoexcitation significantly enhances lithium salt dissociation, increasing the concentration of mobile Li+. This results in a substantial increase in ionic conductivity, reaching 0.135 mS cm1 at 25 °C, with a Li+ transference number as high as 0.46. The flexible all-solid-state lithium-metal pouch cells exhibit an impressive discharge capacity of 178.8 mAh g1 even after repeated bending and folding, and demonstrate exceptional long-term cycling stability, retaining 86.7% of their initial capacity after 250 cycles at 1 C (25 °C). This research offers a novel approach to developing high-performance flexible lithium-metal batteries.

DOI: 10.1002/anie.202417605

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202417605