北京理工大学陈人杰团队报道了一种增强Li-O₂电池界面稳定性和液相放电的超分子深共晶电解质。相关研究成果于2024年9月2日发表在《德国应用化学》。

Li-O₂电池（LOBs）因其卓越的能量密度而得到了广泛的认可。然而，LOBs面临的一个主要挑战是缺乏能够有效平衡反应物传输、界面相容性和非挥发性的适当电解质。

为了解决这个问题，基于锂盐（LiTFSI）、乙酰胺（Ace）和硼酸（BA）的组合，Li键和氢键之间的协同作用，研究人员开发了一种新型超分子深共晶电解质（DEE）。BA的掺入用作界面改性添加剂，同时充当Li键受体和氢键供体/受体，从而增强电解质的氧化还原稳定性，促进溶液相放电过程，并改善与Li阳极的兼容性。

DEE在LOBs中显示出4.5 V的高氧化电压、15225 mAh g^-1的超高放电容量和196次循环的稳定循环性能。此外，Li-O₂袋式电池的固有不可燃性和成功运行表明这种电解质具有广阔的实际应用前景。

该项研究拓宽了LOBs电解质的设计可能性，并为未来的研究提供了理论见解。

附：英文原文

Title: A Supramolecular Deep Eutectic Electrolyte Enhancing Interfacial Stability and Solution Phase Discharge in Li-O2 Batteries

Author: Wen Sun, Fengling Zhang, Jingning Lai, Bohua Li, Xin Hu, Boshun Gui, Nuo Chen, Xingming Guo, Zhujie Li, Nan Chen, Li Li, Feng Wu, Renjie Chen

Issue&Volume: 2024-09-02

Abstract: Li-O2 batteries (LOBs) have gained widespread recognition for their exceptional energy densities. However, a major challenge faced by LOBs is the lack of appropriate electrolytes that can effectively balance reactant transport, interfacial compatibility, and non-volatility. To address this issue, a novel supramolecular deep eutectic electrolyte (DEE) has been developed, based on synergistic interaction between Li-bonds and H-bonds through a combination of lithium salt (LiTFSI), acetamide (Ace) and boric acid (BA). The incorporation of BA serves as an interface modification additive, acting as both Li-bonds acceptor and H-bonds donor/acceptor, thereby enhancing the redox stability of the electrolyte, facilitating a solution phase discharge process and improving compatibility with the Li anode. Our proposed DEE demonstrates a high oxidation voltage of 4.5 V, an ultrahigh discharge capacity of 15225 mAh g1 and stable cycling performance of 196 cycles in LOBs. Additionally, the intrinsic non-flammability and successful operation of a Li-O2 pouch cell indicate promising practical applications of this electrolyte. This research broadens the design possibilities for LOBs electrolytes and provides theoretical insights for future studies.

DOI: 10.1002/anie.202409965

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202409965