Liu Xu, Zhang Tianyu, Shi Xixi, Ma Yue, Song Dawei, Zhang Hongzhou, Liu Xizheng, Wang Yonggang, Zhang Lianqi
Tianjin Key Laboratory for Photoelectric Materials and Devices, School of Materials Science and Engineering, Tianjin University of Technology, Tianjin, 300384, China.
Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Institute of New Energy, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Fudan University, Shanghai, 200433, China.
Adv Sci (Weinh). 2022 Jul;9(20):e2104531. doi: 10.1002/advs.202104531. Epub 2022 May 7.
The silicon oxide/graphite (SiO/C) composite anode represents one of the promising candidates for next generation Li-ion batteries over 400 Wh kg . However, the rapid capacity decay and potential safety risks at low temperature restrict their widely practical applications. Herein, the fabrication of sulfide-rich solid electrolyte interface (SEI) layer on surface of SiO/C anode to boost the reversible Li-storage performance at low temperature is reported. Different from the traditional SEI layer, the present modification layer is composed of inorganic-organic hybrid components with three continuous layers as disclosed by time-of-flight secondary ion mass spectrometry (TOF-SIMS). The result shows that ROSO Li, ROCO Li, and LiF uniformly distribute over different layers. When coupled with LiNi Co Mn O cathode, the capacity retention achieves 73% at -20 °C. The first principle calculations demonstrate that the gradient adsorption of sulfide-rich surface layer and traditional intermediate layer can promote the desolvation of Li at low temperature. Meanwhile, the inner LiF-rich layer with rapid ionic diffusion capability can inhibit dendrite growth. These results offer new perspective of developing advanced SiO/C anode and low-temperature Li-ion batteries.
氧化硅/石墨（SiO/C）复合负极是下一代能量密度超过400 Wh kg的锂离子电池的理想候选材料之一。然而，其快速的容量衰减和低温下潜在的安全风险限制了它们的广泛实际应用。在此，报道了在SiO/C负极表面制备富含硫化物的固体电解质界面（SEI）层以提高其低温下可逆锂存储性能的方法。与传统的SEI层不同，通过飞行时间二次离子质谱（TOF-SIMS）揭示，当前的改性层由具有三个连续层的无机-有机混合成分组成。结果表明，ROSO Li、ROCO Li和LiF均匀分布在不同层中。当与LiNi Co Mn O正极耦合时，在-20°C下容量保持率达到73%。第一性原理计算表明，富含硫化物的表面层和传统中间层的梯度吸附可以促进低温下Li的去溶剂化。同时，具有快速离子扩散能力的内部富LiF层可以抑制枝晶生长。这些结果为开发先进的SiO/C负极和低温锂离子电池提供了新的视角。
