Cost-Effective Processing of Nickel-Rich Layered Cathodes for Li Batteries

Sunday, 9 October 2022: 14:40
Galleria 1 (The Hilton Atlanta)
K. Z. Fung and S. Y. Tsai (National Cheng Kung University)
The layered structured cathode material can provide a higher capacity and stable cycle retention, which is a desired property for lithium-ion batteries. Among them, NMC composed of Ni, Mn and Co as transition metals is considered a promising positive electrode. However, because Co is slightly toxic and an expensive strategic resource, reducing the Co content and maintaining the capacitance and cycle stability are the objectives of this study.

In this study, LiNi0.8Mn0.1Co0.1O2 were investigated. Adjust the amount of Li2CO3 and the temperature of calcination to control the size of the crystal grains to achieve better retention. The value of the I(003) and I(104) ratio in XRD pattern represent cation mixing in layered structure. And this parameter is closely related to its electrochemical properties. Discussion will be carried out based on the results of XRD analysis and the charge–discharge profiles and cycling performance.

The layered structured cathode material may provide a high capacity and stable cycle retention, which is a desired property for lithium-ion batteries. Among them, NMC composed of Ni, Mn and Co as transition metals is considered a promising positive electrode. However, because Co is slightly toxic and an expensive strategic resource, reducing the Co content and maintaining high capacity and cycle stability are the objectives of this study. In addition, the fabrication of NMC adopting single-crystal (grain size: 1~6 mm) process tends to give better long-term performance than ones with particles in nanometer range.

In this study, LiNi0.8Mn0.1Co0.1O2 (NMC811) with substitution of Ni/Mn for Co were selected as the Ni-rich layered cathode investigated. Due to the low melting point of Li2CO3, the heating temperature/time of powder mixture become crucial to control the adequate grain size of to achieve better retention. The value of the I(003) and I(104) ratio in XRD pattern represent cation mixing in layered structure. And this parameter is closely related to its electrochemical properties. Discussion will be carried out based on the results of XRD analysis and the charge–discharge profiles and cycling performance.