Multifunctionality of cerium decoration in enhancing the cycling stability and rate capability of a nickel-rich layered oxide cathode

Shuaipeng Hao; Dianwei Zhang; Yunjiao Li; Xiaoming Xi; Shan Wang; Xiaohui Li; Xinjie Shen; Shuaiwei Liu; Junchao Zheng

doi:10.1039/d1nr05912b

Multifunctionality of cerium decoration in enhancing the cycling stability and rate capability of a nickel-rich layered oxide cathode

Nanoscale. 2021 Dec 13;13(47):20213-20224. doi: 10.1039/d1nr05912b.

Authors

Shuaipeng Hao^{1

2}, Dianwei Zhang^{1

2}, Yunjiao Li^{1

2}, Xiaoming Xi³, Shan Wang^{1

2}, Xiaohui Li^{1

2}, Xinjie Shen^{1

2}, Shuaiwei Liu^{1

2}, Junchao Zheng^{1

2}

Affiliations

¹ School of Metallurgy and Environment, Central South University, Changsha, 410083, PR China.
² Engineering Research Center of the Ministry of Education for Advanced Battery Materials, Central South University, Changsha 410083, China.
³ Changsha Research Institute of Mining and Metallurgy, Changsha 410083, PR China.

PMID: 34850803
DOI: 10.1039/d1nr05912b

Abstract

The structural collapse and surface chemical degradation of nickel-rich layered oxide cathodes (NCM) of lithium-ion batteries during operation, which result in severe capacity attenuation, are the major challenges that hinder their commercial development. To improve the cycle and rate performances of LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811), in this study, we have constructed a double-shell structure protective layer with a surface CeO_2-x coating and interfacial spinel-like phase, which mitigate particle microcrack formation and isolate the NCM811 particles from electrolyte erosion. Additionally, during heat-treatment calcination, tetravalent cerium ions with strong oxidation ability can be partially doped into the material, which causes partial oxidation of Ni²⁺ to Ni³⁺, thereby reducing the Li⁺/Ni²⁺ mixing. The strong Ce-O bonds formed in the lattice help to improve the stability of the structure in the highly de-lithiated state. Thus, the synergy of multifunctional cerium modification effectively improves the structural stability and electrochemical kinetics of the material during cycling. Impressively, the obtained Ce-NCM811 exhibits capacity retention of 80.3% at a high discharge rate of 8 C after 500 cycles, which is much higher than that of the pristine cathode (only 44.3%). This work successfully designed a material with multi-functional Ce modification to provide a basis for Ni-rich cathode materials, which is crucial as it effectively improves the electrochemical performance.