Effect of dispersant on cathode slurry of graphene

The slurry of ternary materials LiNi_1/3Mn_1/3Co_1/3O₂/grapheme composites as cathode materials was effectively dispersed via adding Primary Alcobol Ethoxylate (AEO9). By scanning electron microscopy (SEM), electrochemical workstation and galvanostatic charge-discharge tests, the positive tab with different quality of dispersants were characterized for morphology, electrical properties and internal resistance. The results show that the positive electrode exhibits the best electric conductivity, the lowest interfacial resistance and the best electrochemical performance while 0.4 % of the dispersant is added to the slurry which makes the most effective dispersion. Within the range of 2.75~ 4.2 V and under 1 C charged and 6 C discharged, the discharged capacity will be reduced from 126 mAh/g to 106.2 mAh/g after 500 cycles and with the capacity retention ration at 84.2 % while discharge capacity retention ratio of battery without dispersant is 80 %.