Long Kecheng, Liu Xinsheng, Yang Jixu, Wang Han, Wang Anbang, Chen Yuejiao, Mei Lin, Zhang Yu, Wu Zhibin, Wang Weikun, Jin Zhaoqing, Chen Libao
State Key Laboratory of Powder Metallurgy, Central South University, Changsha, 410083, P. R. China.
Research Institute of Chemical Defense, Beijing, 100191, China.
Small. 2024 Sep;20(36):e2311193. doi: 10.1002/smll.202311193. Epub 2024 May 13.
LiB alloy is promising lithium (Li) metal anode material because the continuous internal LiB fiber skeleton can effectively suppress Li dendrites and structural pulverization. However, the unvalued surface states limit the practical application of LiB alloy anodes. Herein, the study examined the influence of the different exposure manners of the internal LiB fiber skeleton owing to the various surface states of the LiB alloy anode on electrochemical performance and targetedly proposed a scalable friction coating strategy to construct a lithiated fumed silica (LFS) functional layer with abundant electrochemically active sites on the surface of the LiB alloy anode. The LFS significantly suppresses the inhomogeneous interfacial electrochemical behavior of the LiB alloy anode and enables the exposure of the internal LiB fiber skeleton in a homogeneously planar manner (LFS-LiB). Thus, a 0.5 Ah LFS-LiB||LiCoO (LCO) pouch cell exhibits a discharge capacity retention rate of 80% after 388 cycles. Moreover, a 6.15 Ah LFS-LiB||S pouch cell with 409.3 Wh kg exhibits a discharge capacity retention rate of 80% after 30 cycles. In conclusion, the study findings provide a new research perspective for Li alloy anodes.
锂硼合金是一种很有前景的锂金属负极材料，因为连续的内部锂硼纤维骨架可以有效抑制锂枝晶和结构粉化。然而，未被重视的表面状态限制了锂硼合金负极的实际应用。在此，该研究考察了由于锂硼合金负极的各种表面状态导致的内部锂硼纤维骨架不同暴露方式对电化学性能的影响，并针对性地提出了一种可扩展的摩擦涂层策略，以在锂硼合金负极表面构建具有丰富电化学活性位点的锂化气相二氧化硅（LFS）功能层。LFS显著抑制了锂硼合金负极不均匀的界面电化学行为，并使内部锂硼纤维骨架以均匀的平面方式暴露（LFS-LiB）。因此，一个0.5 Ah的LFS-LiB||LiCoO（LCO）软包电池在388次循环后放电容量保持率为80%。此外，一个6.15 Ah、409.3 Wh kg的LFS-LiB||S软包电池在30次循环后放电容量保持率为80%。总之，该研究结果为锂合金负极提供了一个新的研究视角。
