Preparation of long-term cycling stable ni-rich concentration-gradient NCMA cathode materials for li-ion batteries

Juliya Jeyakumar; Manojkumar Seenivasan; Yi-Shiuan Wu; She-Huang Wu; Jeng-Kuei Chang; Rajan Jose; Chun-Chen Yang

doi:10.1016/j.jcis.2023.02.064

Preparation of long-term cycling stable ni-rich concentration-gradient NCMA cathode materials for li-ion batteries

J Colloid Interface Sci. 2023 Jun:639:145-159. doi: 10.1016/j.jcis.2023.02.064. Epub 2023 Feb 14.

Authors

Juliya Jeyakumar¹, Manojkumar Seenivasan¹, Yi-Shiuan Wu², She-Huang Wu³, Jeng-Kuei Chang⁴, Rajan Jose⁵, Chun-Chen Yang⁶

Affiliations

¹ Battery Research Center of Green Energy, Ming Chi University of Technology, Taishan, New Taipei, City 24301, Taiwan, ROC; Department of Chemical Engineering, Ming Chi University of Technology, Taishan, New Taipei, City 24301, Taiwan, ROC.
² Battery Research Center of Green Energy, Ming Chi University of Technology, Taishan, New Taipei, City 24301, Taiwan, ROC.
³ Battery Research Center of Green Energy, Ming Chi University of Technology, Taishan, New Taipei, City 24301, Taiwan, ROC; Graduate Institute of Science and Technology, National Taiwan University of Science and Technology, 43, Sec. 4, Keelung Road, Taipei 106, Taiwan, ROC.
⁴ Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan, ROC.
⁵ Nanostructured Renewable Energy Materials Laboratory, Faculty of Industrial Sciences and Technology, University Malaysia Pahang, 26300 Kuantan, Malaysia.
⁶ Battery Research Center of Green Energy, Ming Chi University of Technology, Taishan, New Taipei, City 24301, Taiwan, ROC; Department of Chemical Engineering, Ming Chi University of Technology, Taishan, New Taipei, City 24301, Taiwan, ROC; Department of Chemical and Materials Engineering, and Green Technology Research Center, Chang Gung University, Taoyuan City 333, Taiwan, ROC. Electronic address: ccyang@mail.mcut.edu.tw.

PMID: 36804788
DOI: 10.1016/j.jcis.2023.02.064

Abstract

Nickel-rich (Ni > 90 %) cathodes are regarded as one of the most attractive because of their high energy density, despite their poor stability and cycle life. To improve their performance, in this study we synthesized a double concentration-gradient layered Li[Ni_0.90Co_0.04Mn_0.03Al_0.03]O₂ oxide (CG-NCMA) using a continuous co-precipitation Taylor-Couette cylindrical reactor (TCCR) with a Ni-rich-core, an Mn-rich surface, and Al on top. The concentration-gradient morphology was confirmed through cross-sectional EDX line scanning. The as-synthesized sample exhibited excellent electrochemical performance at high rates (5C/10C), as well as cyclability (91.5 % after 100 cycles and 70.3 % after 500 cycles at 1C), superior to that (83.4 % and 47.6 %) of its non-concentration-gradient counterpart (UC-NCMA). The Mn-rich surface and presence of Al helped the material stay structurally robust, even after 500 cycles, while also suppressing side reactions between the electrode and electrolyte, resulting in better overall electrochemical performance. These enhancements in performance were studied using TEM, SEM, in-situ-XRD, XPS, CV, EIS and post-mortem analyses. This synthetic method enables the highly scalable production of CG-NCMA samples with two concentration-gradient structures for practical applications in Li-ion batteries.

Keywords: Concentration-gradient; In situ XRD; Ni-rich cathodes; Structural stability.