LiNi1/3Mn1/3Co1/3O2 nanoparticles produced by flame spray pyrolysis with crystallinity characteristics similar to commercial NMC particles

Abstract

To achieve higher energy densities in lithium-ion batteries, improvements in the battery cathode performance are crucial. As cathode materials, nickel-rich layered transition metal oxides play an important role in the market. However, they suffer from surface degradation which contributes to the capacity fade. Using nanoparticles, which offer a large surface to volume ratio, these surface degradation reactions can be better understood. But to do so, nanoparticles with properties similar to those of primary particles in commercial NMC are necessary. In this work, we present the synthesis of sub-100 nm of LiNi_1/3Mn_1/3Co_1/3O₂ (NMC111) nanoparticles through a flame spray pyrolysis and post-calcination. We study the phase purity and electrochemical performance of the NMC111 nanoparticles as a function of the calcination temperature and demonstrate that optimizing the calcination temperature enables us to achieve a pure layered phase and electrochemical performance on par with commercial NMC111 particles. Mild acid treatment can be used to remove surface impurities that develop with air exposure and improve the long-term stability.