Stabilization of crystal and interfacial structure of Ni-rich cathode material by vanadium-doping

Chengxiang Mei; Fanghui Du; Ling Wu; Zhongxu Fan; Qi Hao; Tao Xu; Huazhang Guo; Junwei Zheng

doi:10.1016/j.jcis.2022.03.004

Stabilization of crystal and interfacial structure of Ni-rich cathode material by vanadium-doping

J Colloid Interface Sci. 2022 Jul:617:193-203. doi: 10.1016/j.jcis.2022.03.004. Epub 2022 Mar 2.

Authors

Chengxiang Mei¹, Fanghui Du², Ling Wu³, Zhongxu Fan¹, Qi Hao¹, Tao Xu¹, Huazhang Guo⁴, Junwei Zheng⁵

Affiliations

¹ College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China.
² Shandong Key Laboratory of Chemical Energy Storage and New Battery Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
³ School of Iron and Steel, Soochow University, Suzhou 215137, China. Electronic address: lwu@suda.edu.cn.
⁴ Institute of Nanochemistry and Nanobiology, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
⁵ College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China. Electronic address: jwzheng@suda.edu.cn.

PMID: 35276520
DOI: 10.1016/j.jcis.2022.03.004

Abstract

Stable structure and interface of nickel-rich metal oxides is crucial for practical application of next generation lithium-ion batteries with high energy density. Bulk doping is the promising strategy to improve the structural and interfacial stability of the materials. Herein, we report the impact of vanadium-doping on the structure and electrochemical performance of LiNi_0.88Co_0.09Al_0.03O₂ (NCA88). Vanadium doped in high oxidation state (+5) would lead to alteration of the crystal lattice and Li⁺/Ni²⁺ cation mixing. Those are the main factors determining the cycling and rate capability of the materials. With optimization of vanadium-doping, the preservation of the integrity of the secondary particles of the materials, the enhancement of the diffusion of Li⁺ ions, and alleviation of the side reactions of the electrolyte can be efficiently achieved. As a result, NCA88 doped with vanadium of 1.5 mol % can provide superior cycling stability with capacity retention of 84.3% after 250 cycles at 2C, and rate capability with capacity retention of 65.5% at 10C, as compared to the corresponding values of 58.6% and 55% for the pristine counterpart, respectively. The results might be helpful to the selection of dopants in the design of the nickel-rich materials.

Keywords: Interface; Lithium-ion batteries; Nickel-rich cathode; Sol–gel; Vanadium-doping.