Chlorination behavior of Li(Ni1/3Co1/3Mn1/3)O2

The chlorination behavior of Li(Ni1/3Co1/3Mn1/3)O-2 (NCM) was investigated as a function of the reaction temperature (400-600 degrees C) and time (1-8 h) for application in a chlorination-based recycling process. Structural analysis results revealed that chlorination leads to a sequential transition from a hexagonal LiMO2 structure to a hexagonal Li1-x ' MO2-y ' (observed only at 400 degrees C), a hexagonal Li1-xMO2-y (x >= x ', y >= y ', at 400-600 degrees C), and a spinel-type M3O4 phase (>= 500 degrees C, M represents Ni,Co,Mn). It was also found that this structural transition is accelerated by an increase in the reaction temperature, except at 600 degrees C, where the thermal decomposition of the Li1-xMO2-y phase inhibited the formation of the M3O4 phase. Weight changes of the samples suggested that the chlorination of the transition metals begins at 500 degrees C and that its rate increases with an increase in the reaction temperature. It was revealed by a composition analysis that an increase in the reaction temperature (except at 600 degrees C) and longer times result in a higher Li removal ratio. A temperature of 550 degrees C was proposed as the optimum temperature for the chlorination of NCM in consideration of the findings from this work.