Carbonaceous material for negative electrodes of nonaqueous electrolyte secondary batteries and method for producing same
View Patent ↗Provided is a manufacturing method of carbonaceous material for a negative electrode of non-aqueous electrolyte secondary batteries, wherein the carbonaceous material is obtained from plant-derived char as a source, potassium is sufficiently removed, and an average particle diameter thereof is small; and a carbonaceous material for a negative electrode of non-aqueous electrolyte secondary batteries. The method for manufacturing a carbonaceous material having an average particle diameter of 3 to 30 μm, for a negative electrode of non-aqueous electrolyte secondary batteries includes the steps of: (1) heating plant-derived char having an average particle diameter of 100 to 10000 μm at 500° C. to 1250° C. under an inert gas atmosphere containing halogen compound to demineralize in a gas-phase, (2) pulverizing a carbon precursor obtained by demineralization in a gas-phase, (3) calcining the pulverized carbon precursor at 1000° C. to 1600° C. under an non-oxidizing gas atmosphere.
1. A method for manufacturing a carbonaceous material having an average particle diameter of 3 to 30 μm, for a negative electrode of non-aqueous electrolyte secondary batteries comprising the steps of:
(1) heating plant-derived char having an average particle diameter of 100 to 10000 μm at 850° C. to 1250° C. under an inert gas atmosphere containing a chlorine compound to demineralize the plant-derived char in a gas-phase,
(2) pulverizing a carbon precursor obtained by the demineralization of the plant-derived char in a gas-phase, and
(3) heat treating the pulverized carbon precursor at 1000° C. to 1600° C. under a non-oxidizing gas atmosphere.
2. The method for manufacturing a carbonaceous material for a negative electrode of non-aqueous electrolyte secondary batteries according to claim 1 , further comprises a step of removing particles having a particle diameter of 1 μm or less so that an amount of the particle diameter of 1 μm or less became 3 volume % or less in the pulverized carbon precursor, during or after the pulverizing step (2).
3. A carbonaceous material for a negative electrode of non-aqueous electrolyte secondary batteries, obtained by the method of claim 1 ,
wherein an average particle diameter is 3 to 30 μm,
an amount of element potassium is 0.1 weight % or less, and
an amount of element iron is 0.02 weight % or less.
4. The carbonaceous material according to claim 3 , comprising particles having a particle diameter of 1 μm or less account for 3.0 volume % or less.
5. The carbonaceous material according to claim 3 , comprising a specific surface area is 1 to 50 m 2 /g.
6. A negative electrode of a non-aqueous electrolyte secondary battery comprising the carbonaceous material according to claim 3 .
7. The negative electrode of a non-aqueous electrolyte secondary battery according to claim 6 , wherein an active material layer exists on one surface or both surfaces of a metal current collector, and a thickness of the active material layer on one surface is 80 μm or less.
8. A non-aqueous electrolyte secondary battery comprising the negative electrode according to claim 6 .
9. A non-aqueous electrolyte secondary battery comprising the carbonaceous material according to claim 3 .
10. A vehicle having the non-aqueous electrolyte secondary battery according to claim 9 .