Zhao Junkang, Zhu Xiayu, Zhang Wenfeng, Qiu Jingyi, Zhai Feiyue, Zhang Huimin, Cao Gaoping, Gao Shengji, Ding Fei, Xiang Yu
Hebei University of Technology Tianjin 100131 China
Chemical Defense Institute, Academy of Military Sciences Beijing 100191 China
RSC Adv. 2024 Apr 9;14(16):11276-11283. doi: 10.1039/d4ra00832d. eCollection 2024 Apr 3.
Due to their small interlayer spacing and a low lithiation potential close to Li deposition, current graphite anodes suffer from weak kinetics, and lithium deposition in a fast-charging process, hindering their practical application in high-power lithium-ion batteries (LIBs). In this work, expanded graphite incorporated with LiTiO nanoparticles (EG/LTO) was synthesized moderate oxidization of artificial graphite following a solution coating process. The EG/LTO has sufficient porosity for fast Li diffusion and a dense LiTiO layer for decreased interface reaction resistance, resulting in excellent fast-charging properties. EG/LTO presented a high reversible capacity of 272.8 mA h g at 3.74 A g (10C), much higher than that of the original commercial graphite (50.1 mA h g at 10C) and even superior to that of hard carbon. In addition, EG/LTO exhibited capacity retention rate of 98.4% after 500 cycles at 10C, demonstrating high structural stability during a long cycling process. This study provides a protocol for a solution chemistry method to prepare fast-charging graphite anode materials with high stability for high-power LIBs.
由于其层间距小且锂化电位低接近锂沉积，目前的石墨负极存在动力学较弱以及在快速充电过程中锂沉积的问题，这阻碍了它们在高功率锂离子电池（LIBs）中的实际应用。在这项工作中，通过溶液涂覆工艺对人造石墨进行适度氧化，合成了掺入LiTiO纳米颗粒的膨胀石墨（EG/LTO）。EG/LTO具有足够的孔隙率以实现快速锂扩散以及致密的LiTiO层以降低界面反应电阻，从而具有优异的快速充电性能。EG/LTO在3.74 A g（10C）下具有272.8 mA h g的高可逆容量，远高于原始商业石墨在10C时的容量（50.1 mA h g），甚至优于硬碳。此外，EG/LTO在10C下循环500次后容量保持率为98.4%，表明在长循环过程中具有高结构稳定性。本研究提供了一种溶液化学方法的方案，用于制备具有高稳定性的高功率LIBs快速充电石墨负极材料。
