Negative electrode active material for lithium ion battery

Abstract

The present invention provides a negative electrode active material for lithium ion batteries which has high adhesiveness and followability to a negative electrode active material in volume expansion and contraction during charging and discharging, excellent contact and adhesiveness to a conductive aid, a binder, and a current collector, and a high suppressing effect on decomposition of an electrolyte solution. Due to these features, the negative electrode active material for lithium ion batteries is capable of achieving excellent cycle characteristics and rate characteristics and high coulombic efficiency. The present invention also provides a negative electrode for lithium ion secondary batteries and a lithium ion secondary battery each including the negative electrode active material for lithium ion batteries, and a method for producing a negative electrode active material for lithium ion batteries. Provided is a negative electrode active material for lithium ion batteries, including: a negative electrode active material; and a coating layer containing an amorphous carbon on a surface of the negative electrode active material, the amorphous carbon constituting the coating layer having a ratio of a peak derived from a sp2 component to a peak derived from a sp3 component of 1 or higher as determined byC solid-state NMR, and a ratio of a peak derived from aromatic carbon having a bond with a hydroxy group to the peak derived from the sp2 component of 0.2 or lower.