Large-Scale Electric-Field Confined Silicon with Optimized Charge-Transfer Kinetics and Structural Stability for High-Rate Lithium-Ion Batteries
作者: Meng, T (Meng, Tao); Li, B (Li, Bo); Wang, QS (Wang, Qiushi); Hao, JN (Hao, Junnan); Huang, BB (Huang, Binbin); Gu, FL (Gu, Feng Long); Xu, HM (Xu, Huimin); Liu, P (Liu, Peng); Tong, YX (Tong, Yexiang)
标题: Large-Scale Electric-Field Confined Silicon with Optimized Charge-Transfer Kinetics and Structural Stability for High-Rate Lithium-Ion Batteries
来源出版物: ACS NANO
卷: 14
期: 6
页: 7066-7076
DOI: 10.1021/acsnano.0c01796
出版年: JUN 23 2020
摘要: The stereospecific design of the interface effects can optimize the electron/Li-ion migration kinetics for energy-storage materials. In this study, an electric field was introduced to silicon-based materials (C-SiOx@Si/rGO) through the rational construction of multi-heterostructures. This was achieved by manipulating the physicochemical properties at the atomic level of advanced Li-ion batteries (LIBs). The experimental and density functional theory calculations showed that the unbalanced charge distribution generated a large potential difference, which in turn induced a large-scale electric-field response with a boosted interfacial charge transfer in the composite. The as-prepared C-SiOx@Si/rGO anode showed advanced rate capability (i.e., 1579.0 and 906.5 mAh g(-1) at 1000 and 8000 mA g(-1), respectively) when the migration paths of the Li-ion/electrons hierarchically optimized the large electric field. Furthermore, the C-SiOx@Si/rGO composite with a high SiOx@Si mass ratio (73.5 wt %) demonstrated a significantly enhanced structural stability with a 40% volume expansion. Additionally, when coupled with the LiNi0.8Co0.1Mn0.1O2 (NCM) cathode, the NCM//C-SiOx@Si/rGO full cell delivers superior Li-ion storage properties with high reversible capacities of 157.6 and 101.4 mAh g(-1) at 500 and 4000 mA g(-1), respectively. Therefore, the electric-field introduction using optimized electrochemical reaction kinetics can assist in the construction of other high-performance LIB materials.
关键词
作者关键词:interface effects; electric field; silicon-based materials; charge redistribution; density functional theory; Li-ion storage properties
KeyWords Plus: INITIO MOLECULAR-DYNAMICS; AMORPHOUS-SILICON; ANODE MATERIALS; HIGH-CAPACITY; FILM ANODE; SI; MICROSPHERES; NANOSHEETS; EVOLUTION; BINDER