| 摘要 |
There is provided a carbon material for a negative electrode of a lithium ion secondary battery which is capable of maintaining a high level of charge and discharge capacity and suppressing capacity degradation which will occur due to repetition of a charge and discharge cycle, storage under a charged state, and float charging. The carbon material for a negative electrode of a lithium ion secondary battery includes: particles having a structure including a plurality of stacked plates which are prepared from a raw coke materials obtained by a delayed coking method, where the ratio of the total of the generation rate (mass%) of a hydrogen gas, a hydrocarbon gas having one carbon atom (C1 gas), and a hydrocarbon gas having two carbon atoms (C2 gas) to be generated by subjecting a heavy oil to coking and the formation rate (mass%) of a raw coke materials satisfies the condition: total of generation rate/formation rate = 0.30 to 0.60, and where the structure is curved into a bow shape, and where, in each of the plates, an average plate thickness is defined as T, an average bow height including the plate thickness is defined as H, and an average length in the vertical direction is defined as L, L/T is 5.0 or more and H/T is from 1.10 to 1.25. |
