Non-aqueous electrolyte secondary battery, method of evaluating negative electrode composite material layer, and method of producing non-aqueous electrolyte secondary battery

A method of evaluating a negative electrode composite material layer,

• the method comprising at least:
• preparing a negative electrode composite material layer;
• and
• performing evaluation of the negative electrode composite material layer,
• the negative electrode composite material layer including a negative electrode active material, a conductive material, and a binder,
• the negative electrode active material including a silicon oxide material and a graphite material,
• the evaluation of the negative electrode composite material layer being performed based on an elongation of the negative electrode composite material layer at a bending point in a plot made by:
• stretching the negative electrode composite material layer by 1% in a direction orthogonal to a thickness direction of the negative electrode composite material layer;
• performing measurement of an electrical resistance of the negative electrode composite material layer thus stretched;
• repeating the stretching in the same direction while each stretching is followed by the measurement;
• and
• making a plot of values thus obtained by the measurement, the plot being made on an orthogonal coordinate system, the orthogonal coordinate system having an abscissa representing the elongation of the negative electrode composite material layer and an ordinate representing the electrical resistance of the negative electrode composite material layer.