Structural developments of artificial graphite scraps in further graphitization and its relationships with discharge capacity

Petroleum coke graphite (PCG) and needle coke graphite (NCG) scraps with different aggregate and morphology were selected. The structural developments in the temperature range from 2400°C to 3000°C showed that the graphite crystallites in samples increased faster in the base plane direction (100) compared to that in the vertical direction (002). The crystallite volume of sample NCG is much bigger than the sample PCG under each condition because the former is easier to be graphitized to the latter. The discharge capacity of graphite scrap anode was mainly determined by its crystallite parameters. Although the discharge capacities of samples PCG or NCG were well fitted with their crystallite parameters separately, the correlation coefficients between the capacities and Lc, La and V of all the samples decreased. This is because big differences exist in the parameters of different samples. The discharge capacity of graphite anode still depends strongly on graphitization degree even if additional four needle coke artificial graphite scraps are introduced into the group of samples PCG and NCG. The equation obtained is D=166.9+1.8584×G, in which its correlation coefficient is as high as 0.9744.