Issue 17, 2024

Integrating surface modification to improve the electrochemical performance of Li-rich cathode materials

Abstract

Li-rich cathode materials (LLO) exhibit a high specific capacity, but their application is impeded by their poor cycling stability and rate performance which arises from the irreversible anionic redox reaction and their poor electrical conductivity. In this regard, a simple phytic acid surface treatment technique was employed to form an integrated surface structure comprising Li3PO4 and oxygen vacancies (Vos) on the surface of LLO materials. In particular, the effect of the Li3PO4 layer on the defect structure and their synergistic effect on the electrochemical performances of LLO were researched through experimental and theoretical calculations. The results prove that the existence of Li3PO4 can improve the Vo content obviously. The coating layer and the synchronously formed Vo can also facilitate Li+ diffusion, improve the electrical conductivity, and inhibit the irreversible O2 release effectively, thus increasing the cycling stability and rate performance of LLO. Consequently, the initial coulombic efficiency (ICE) increases from 62.8% to 72%. After 200 cycles at 0.5C, the capacity retention has improved significantly from 78% to 92.3%, accompanied by a minimal voltage fading value of 108.8 mV. The discharge specific capacity still reaches 125 mA h g−1 even at a current density of 5C. This work proves the effect of the Li3PO4 coating layer on the defect structure and electrochemical properties of the LLO material and provides an effective clue to improve its performance.

Graphical abstract: Integrating surface modification to improve the electrochemical performance of Li-rich cathode materials

Supplementary files

Article information

Article type
Research Article
Submitted
26 Mar 2024
Accepted
07 Jul 2024
First published
16 Jul 2024

Inorg. Chem. Front., 2024,11, 5517-5527

Integrating surface modification to improve the electrochemical performance of Li-rich cathode materials

X. Zhang, Y. Gao, X. Li, W. Liu, H. Zhang, S. Yang and Y. Yin, Inorg. Chem. Front., 2024, 11, 5517 DOI: 10.1039/D4QI00769G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements