Understanding the effect of surface coating and elemental doping on mitigating the decomposition of LiNiO2 and LiNi0.8Mn0.1Co0.1O2 cathode powders

LiNiO2 and LiNi0.8Mn0.1Co0.1O2 are promising cathode materials for next-generation high-energy-density Li-ion battery cathodes. However, their strong sensitivity to moisture and air prevents their industrial commercialisation. They react with H2O, CO2 and O2 under ambient conditions to form impurities such as LiOH and Li2CO3, which also leads to structural transitions in the parent material, thereby worsening their electrochemical performance. Therefore, these cathode materials are typically processed in dry rooms, which are expensive to maintain. Thus, reducing their sensitivity to ambient atmospheric conditions through either surface coating techniques or elemental doping, will make their processing simpler and cheaper, thereby directly facilitating their commercialisation. In this proposal, we intend to use in situ neutron diffraction studies to investigate whether these strategies can successfully mitigate the atmospheric degradation of these cathode materials. By following the structural transitions occurring in the parent and modified materials when heated under air through the in situ experiment, we will be able to gauge the utility of these techniques to improve the stability of these materials.