PRODUCING METHOD OF 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 provides a method for producing a negative electrode material for a non-aqueous electrolyte secondary battery, which can produce a negative electrode material having a uniform carbon coating film when using a rotary kiln and allows mass production of a negative electrode material for a non-aqueous electrolyte secondary battery having high capacity and high cycle characteristics. The method for producing a negative electrode material for a non-aqueous electrolyte secondary battery comprises the steps of: preparing particles of a silicon-based negative electrode active material; and carrying out carbon coating by forming a carbon coating film on the surfaces of the particles, wherein the carbon coating uses a rotary kiln and the rotation number (R (rpm)) of the kiln core tube of the rotary kiln, weight of the particles introduced to the kiln core tube per unit time (W (kg/h)) and the inner diameter of the kiln core tube (T (m)) are controlled to satisfy both the following relational expression (1), W / (376.8 x R x T^2) <= 1.0, and relational expression (2), (T x R^2 / 0.353) <= 3.0.