Preparation and corrosion resistance of β-Al2O3 - MgAl2O4 multiphase materials for synthesising Li-ion battery cathode materials

The sagger, primarily composed of aluminum-silicon, serves as an essential vessel in the sintering process of ternary lithium battery anode materials (LiNi(x)CoyMn(1-x-)yO(2), LNCM). However, the acidic oxide SiO(2 )in the sagger material readily reacts with Li2O in the cathode material, forming substances such as LiAlO2 or LiAlSiO4, resulting in volume expansion, which makes the sagger spalled and damaged. In this study, beta-Al2O3-MgAl2O4 multiphase materials with excellent alkali resistance were prepared using the high-temperature solid-state method. The effects of anhydrous sodium carbonate content and heat treatment temperature on the properties of the composites were investigated, and the thermal shock resistance of the specimens was evaluated by the water- rapid-cooling method, as well as the LNCM corrosion resistance of the specimens was evaluated by the static crucible method. The results showed that the overall performance of the specimens was the best at a anhydrous sodium carbonate content of 6 wt%, with a compressive strength of 57.50 MPa and a flexural strength of 42.49 MPa after firing at 1600 degrees C for 4 h. The strength retention of the specimens was 33.21 % after one thermal shock at a thermal shock temperature of 900 degrees C. The specimens showed excellent resistance to erosion as there were no obvious erosion traces on the surface of the specimens after undergoing five cycles of erosion.