Understanding the Role of Temperature and Cathode Composition on Interface and Bulk: Optimizing Aluminum Oxide Coatings for Li-Ion Cathodes

• DOI: 10.1021/acsami.7b00595
• Publication Date: 2017-04-07T14:40:36Z
• Authors: Binghong Han; Tadas Paulauskas; Baris Key; Cameron Peebles; Joong Sun Park; Robert F. Klie; John T. Vaughey; Fulya Dogan
• Keywords: 02 engineering and technology; 0210 nano-technology

Surface coating of cathode materials with Al2O3 has been shown to be a promising method for stabilization and improved cycling performance at high operating voltages. However, detailed understanding on how process composition change the chemical composition, morphology, distribution within interface bulk lattice is still missing. In this study, we use wet-chemical synthesize series Al2O3-coated LiNi0.5Co0.2Mn0.3O2 LiCoO2 cathodes treated under various annealing temperatures combination structural characterization techniques understand homogeneity, morphology layer cathode. Nuclear magnetic resonance electron microscopy results reveal that nature highly dependent temperature composition. For LiNi0.5Co0.2Mn0.3O2, higher leads more homogeneous closely attached materials, corresponding better electrochemical performance. Lower content found helpful further improve initial capacity cyclability, which can greatly outperform pristine material. LiCoO2, incorporation Al into observed after temperatures, implying transformation from "surface coatings" "dopants", not LiNi0.5Co0.2Mn0.3O2. As result, annealed shows similar but lower retention compared temperature, due intercalation surface alumina layered structure forming solid solution.