![]() ![]() Publication Date: Research Org.: Argonne National Lab. Chemical Sciences and Engineering Division The diffusion of Al into the bulk was found to be detrimental to the protection function of surface coatings leading to poor overall cyclability, indicating the importance of compatibility between surface coatings and bulk oxides on the electrochemical performance of coated cathode materials.In conclusion, these results are important in developing a better coating method for synthesis of next-generation cathode materials for lithium-ion batteries. Structural characterization of pristine NMC particles also suggests surface Co segregation, which may act to mediate the more » diffusion of the Al from the surface to the bulk. The presence of a high surface Li concentration and strong alumina diffusion into the bulk led to a smoother surface coating on NMC811 with no excess alumina aggregated on the surface. It was also noted that the cathode composition affected the observed morphology and surface chemistry of the coated material, which has an effect on electrochemical cycling. By use of a variety of spectroscopic techniques, Al was seen to have a high bulk compatibility with higher Ni/Co content, and low bulk compatibility was associated with Mn in the transition metal layer. Changing cathode composition from LiNi 0.5Mn 0.3Co 0.2O 2 (NMC532) to LiNi 0.6Mn 0.2Co 0.2O 2 (NMC622) and LiNi 0.8Mn 0.1Co 0.1O 2 (NMC811) was found to facilitate the diffusion of surface alumina into the bulk after high-temperature annealing. In this work, we systematically studied the effect of the composition of Ni-rich LiNi xMn 圜o 1–x–yO 2 (NMC) on the surface alumina coatings. However, a detailed understanding of the relationship between the surface coatings and the bulk layered oxides is needed to better define the critical cathode–electrolyte interface. Surface alumina coatings have been shown to be an effective way to improve the stability and cyclability of cathode materials. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |