MATERIAL FOR CATHODE AND METHOD OF ITS MANUFACTURE

摘要

A material for a cathode is made of a carbon material hard to turn to graphite and obtainable by burning a carbon precursor. For this carbon material having the graphitization resistance, the weight % Ps of carbon in the material is smaller than 0.59 or the stacking index SI is smaller than 0.76. This carbon has a structure of stacked layers, which is determined by the diffraction peak due to the (002) plane of the crystal lattice, and the X-ray diffraction spectrum on the side of an angle lower than the diffraction peak among the X-ray diffraction spectrum. The average Nave of the number of stacked layers is smaller than 2.46. Alternatively, letting the burning temperature be T DEG C, and the half-width of a peak appearing near 1,340 cm<-1> in the Raman spectrum be HW, the following condition is satisfied: HW > 138-0.06 T. This carbon material is manufactured by thermally treating a carbon precursor by burining it in an inert gas atmosphere flown at a flow rate of 0.1 ml per minute or more per one gram of the carbon precursor at a temperature of 600 DEG C or high, or in an atmosphere pressurized at 50 kPa or less at a temperature of 600 DEG C or high. In this case, the carbon precursor is placed in a layer so that the contact area of the precursor with the atmosphere is 10 cm<2> or more.