Kirkendall effect-induced uniform stress distribution stabilizes nickel-rich layered oxide cathodes

Ziyao Gao; Chenglong Zhao; Kai Zhou; Junru Wu; Yao Tian; Xianming Deng; Lihan Zhang; Kui Lin; Feiyu Kang; Lele Peng; Marnix Wagemaker; Baohua Li

doi:10.1038/s41467-024-45373-1

Kirkendall effect-induced uniform stress distribution stabilizes nickel-rich layered oxide cathodes

Nat Commun. 2024 Feb 19;15(1):1503. doi: 10.1038/s41467-024-45373-1.

Authors

Ziyao Gao^{1

2}, Chenglong Zhao³, Kai Zhou^{1

2}, Junru Wu^{1

2}, Yao Tian¹, Xianming Deng^{1

2}, Lihan Zhang^{1

2}, Kui Lin^{1

2}, Feiyu Kang¹, Lele Peng⁴, Marnix Wagemaker⁵, Baohua Li⁶

Affiliations

¹ Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China.
² School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China.
³ Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China. c.zhao-1@tudelft.nl.
⁴ Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China. penglele@sz.tsinghua.edu.cn.
⁵ Department of Radiation Science and Technology, Delft University of Technology, Mekelweg 15, 2629JB, Delft, the Netherlands. m.wagemaker@tudelft.nl.
⁶ Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China. libh@mail.sz.tsinghua.edu.cn.

Abstract

Nickel-rich layered oxide cathodes promise ultrahigh energy density but is plagued by the mechanical failure of the secondary particle upon (de)lithiation. Existing approaches for alleviating the structural degradation could retard pulverization, yet fail to tune the stress distribution and root out the formation of cracks. Herein, we report a unique strategy to uniformize the stress distribution in secondary particle via Kirkendall effect to stabilize the core region during electrochemical cycling. Exotic metal/metalloid oxides (such as Al₂O₃ or SiO₂) is introduced as the heterogeneous nucleation seeds for the preferential growth of the precursor. The calcination treatment afterwards generates a dopant-rich interior structure with central Kirkendall void, due to the different diffusivity between the exotic element and nickel atom. The resulting cathode material exhibits superior structural and electrochemical reversibility, thus contributing to a high specific energy density (based on cathode) of 660 Wh kg^-1 after 500 cycles with a retention rate of 86%. This study suggests that uniformizing stress distribution represents a promising pathway to tackle the structural instability facing nickel-rich layered oxide cathodes.

Abstract

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