METHOD OF PRODUCING NEGATIVE ELECTRODE MATERIAL FOR NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY, NEGATIVE ELECTRODE MATERIAL FOR NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY, NEGATIVE ELECTRODE FOR NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY, AND LITHIUM-ION SECONDARY BATTERY

摘要

The present invention is a method of producing a negative electrode material for a non-aqueous electrolyte secondary battery, including: preparing silicon-based negative electrode active material particles; and coating each of the prepared particles with a conductive carbon coating by using a rotary kiln while controlling the rotary kiln such that the following relationships (1) and (2) hold true:;W/(376.8×R×T2)≦1.0  (1); and;(T×R2/0.353)≦3.0  (2),where R is a rotation rate (rpm) of the furnace tube of the rotary kiln, W is a mass (kg/h) of the particles that are put in the furnace tube per hour, and T is an inner diameter (m) of the furnace tube. This method can not only efficiently produce a negative electrode material that is coated with a uniform carbon coating and crystallinity, but also mass-produce negative electrode materials having a high capacity and a high cycle performance.

主权项

1. A method of producing a negative electrode material for a non-aqueous electrolyte secondary battery, comprising:
preparing silicon-based negative electrode active material particles; and coating each of the prepared particles with a conductive carbon coating that is mainly made of carbon by using a rotary kiln having a rotatable furnace tube to perform chemical vapor deposition using a hydrocarbon-based gas on the particles in an interior of the furnace tube while agitating the particles put in the interior of the furnace tube by rotating the furnace tube and controlling the rotary kiln such that the following relationships (1) and (2) hold true:
W/(376.8×R×T2)≦1.0  (1); and(T×R2/0.353)≦3.0  (2), where R is a rotation rate (rpm) of the furnace tube of the rotary kiln, W is a mass (kg/h) of the particles that are put in the furnace tube per hour, and T is an inner diameter (m) of the furnace tube.