| 摘要 |
PROBLEM TO BE SOLVED: To provide a carbon material excellent in dispersibility and electric conductivity imparting capability, and also to provide a nonaqueous secondary battery using the carbon material.SOLUTION: The carbon material is composed of: carbon black whose specific surface area is 30 to 70 m/g, and whose ratio between a DBP absorption amount and the specific surface area is 3.0(ml/100)/(m/g) or more; and a carbon nanofiber whose average fiber diameter is 5 to 40 nm, and the carbon material has a cumulative 50% particle diameter d50 of 2.0 to 10.0 μm and a cumulative 90% particle diameter d90 of 20.0 μm or less in the particle size distribution,. It is preferable that the content ratio of the carbon nanofiber is 5 to 35 mass%. In a method for producing the carbon material, a catalyst for carbon nanofiber generation is carried on the carbon black, and a carbon-containing compound is brought into contact with the catalyst. |
