Advancements in Alumina Ultrathin Coatings for Enhanced Electrochemical Performance of Ni-Rich NMC811 Thick Electrodes

Lithium-ion batteries, renowned for their high energy density, face a significant challenge in the development of stable, high-performing, and cost-effective cathode materials. Ni-rich cathodes, while promising, suffer from instability issues such as microcracking, high surface reactivity, phase transformation, and thermal runaway. This study introduces a breakthrough: the application of an alumina (Al2O3) ultrathin coating to enhance the stability of Ni-rich thick electrodes. The uniform distribution of the Al2O3 coating across the electrode acts as a protective barrier, effectively reducing oxygen lattice release and microcracking. Our findings reveal that this atomic layer deposition (ALD) technique markedly boosts the cycling stability of the electrodes. Coated electrodes maintained high specific capacity after long cycling, significantly outperforming uncoated electrodes, which retained only small capacity. This innovative approach shows great potential for the development of high-performance and stable lithium-ion batteries. Figure 1