The mechanism of V-modification in Li2CoSiO4 cathode material for Li-ion batteries: A combined first-principles and experimental study

doi:10.1016/j.electacta.2020.136564

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	The mechanism of V-modification in Li2CoSiO4 cathode material for Li-ion batteries: A combined first-principles and experimental study
	Huai, Liyuan ; Du, Wenqiang ; Zhang, Zhifeng ; Zhang, Xianhui ; Zhang, Zhiyong ; Chen, Zhenlian ; Wu, Jinlei ; Wang, Deyu ; Li, Jun
刊名	ELECTROCHIMICA ACTA
	2020
卷号	353
关键词	ELECTROCHEMICAL PERFORMANCE AB-INITIO REDOX CHEMISTRY OXYGEN REDOX VANADIUM COMPOSITES POLYMORPHS LI2FESIO4 DENSITY DESIGN
DOI	10.1016/j.electacta.2020.136564
英文摘要	Lithium cobalt silicate Li2CoSiO4 (LCSO) is a unique cathode candidate that has the potential to simultaneously achieve both high energy-density and high safety. However, it was plagued with poor electrochemical performances owing to limited effective modification of its polymorphic and electronic structures. Functional groups modification has long been proven to be effective approaches for enhancing chemical/physical properties that are highly desirable for energy storage systems. Here the multivalent vanadium (V) doping to modify the tetrahedral functional groups in LCSO was proposed. Based on density functional theory calculations and experimental analysis, V prefers to be doped at Si site, which improves both the electronic and ionic conductivities of LCSO. First-principles modeling with Madelung matrix analysis reveals that the V-3d-O-2p orbital overlaps largely account for the reduction of the electronic energy gap by similar to 1.40 eV and the lithium migration energy barrier by similar to 0.20 eV Li2CoV0.1Si0.9O4/C shows the highest initial discharge capacity of 220.1 mAh g(-1), compared to only 135.0 mAh g(-1) for Li2CoSiO4/C. The discharge rate and cycling stability are also improved. Electrochemical impedance spectroscopy indicates that charge transfer resistance and Li diffusion resistance are reduced by 22.8% and 53.2%, respectively, after V-modification. (c) 2020 Elsevier Ltd. All rights reserved.
学科主题	Electrochemistry
内容类型	期刊论文
源URL	[http://ir.nimte.ac.cn/handle/174433/20545]
专题	2020专题
作者单位	1.Zhang, XH 2.Li, J (corresponding author), Chinese Acad Sci, Ningbo Inst Mat Technol & Engn, Ningbo 315201, Peoples R China.
推荐引用方式 GB/T 7714	Huai, Liyuan,Du, Wenqiang,Zhang, Zhifeng,et al. The mechanism of V-modification in Li2CoSiO4 cathode material for Li-ion batteries: A combined first-principles and experimental study[J]. ELECTROCHIMICA ACTA,2020,353.
APA	Huai, Liyuan.,Du, Wenqiang.,Zhang, Zhifeng.,Zhang, Xianhui.,Zhang, Zhiyong.,...&Li, Jun.(2020).The mechanism of V-modification in Li2CoSiO4 cathode material for Li-ion batteries: A combined first-principles and experimental study.ELECTROCHIMICA ACTA,353.
MLA	Huai, Liyuan,et al."The mechanism of V-modification in Li2CoSiO4 cathode material for Li-ion batteries: A combined first-principles and experimental study".ELECTROCHIMICA ACTA 353(2020).