Surface Modification of LiNi_0.8 Co_0.15 Al_0.05 O₂ Particles via Li₃ PO₄ Coating to Enable Aqueous Electrode Processing

The successful implementation of an aqueous-based electrode manufacturing process for nickel-rich cathode active materials is challenging due to their high water sensitivity. In this work, the surface of LiNi_0.8 Co_0.15 Al_0.05 O₂ (NCA) was modified with a lithium phosphate coating to investigate its ability to protect the active material during electrode production. The results illustrate that the coating amount is crucial and a compromise has to be made between protection during electrode processing and sufficient electronic conductivity through the particle surface. Cells with water-based electrodes containing NCA with an optimized amount of lithium phosphate had a slightly lower specific discharge capacity than cells with conventional N-methyl-2-pyrrolidone-based electrodes. Nonetheless, the cells with optimized water-based electrodes could compete in terms of cycle life.