A non-aqueous electrolyte secondary battery which has a ratio value of a battery volume (a product of a projected area of the battery including a battery outer casing body and a thickness of the battery) to a rated capacity of 10 cm 3 /Ah or less and a rated capacity of 3 Ah or more, the battery comprising: a power generating element including a positive electrode comprising a positive electrode active material layer containing a positive electrode active material formed on a surface of a positive electrode current collector, a negative electrode comprising a negative electrode active material layer containing a negative electrode active material formed on a surface of a negative electrode current collector, and a separator, wherein the negative electrode active material layer comprises a negative electrode active material represented by the following Formula: [Mathematical Formula 1] α Si material + β carbon material (in the formula, the Si material is a Si-containing alloy; the carbon material is one or two or more kinds selected from the group consisting of graphite, non-graphitizable carbon, and amorphous carbon; α and β represent % by mass of each component in the negative electrode active material layer; and 80 ≤ α + β ≤ 98, 0.1 ≤ α ≤ 40, and 58 ≤ β ≤ 97.9 are satisfied), when area proportions (%) of the Si material and the carbon material in an area of a field of view of each image of cross-sections of the negative electrode active material layer in a case where a plurality of arbitrary places is selected in a plane of the negative electrode active material layer are designated as S (%) and (100 - S) (%), respectively, a difference between the maximum value and the minimum value of S is within 5%; and wherein a variation in coating amount per unit area in the negative electrode active material layer at a plurality of selected sites in a case where a plurality of arbitrary places is selected in a plane of the negative electrode active material layer is within 5%. a power generating element including a positive electrode comprising a positive electrode active material layer containing a positive electrode active material formed on a surface of a positive electrode current collector, a negative electrode comprising a negative electrode active material layer containing a negative electrode active material formed on a surface of a negative electrode current collector, and a separator, wherein a positive electrode comprising a positive electrode active material layer containing a positive electrode active material formed on a surface of a positive electrode current collector, a negative electrode comprising a negative electrode active material layer containing a negative electrode active material formed on a surface of a negative electrode current collector, and a separator, wherein the negative electrode active material layer comprises a negative electrode active material represented by the following Formula: [Mathematical Formula 1] α Si material + β carbon material (in the formula, the Si material is a Si-containing alloy; the carbon material is one or two or more kinds selected from the group consisting of graphite, non-graphitizable carbon, and amorphous carbon; α and β represent % by mass of each component in the negative electrode active material layer; and 80 ≤ α + β ≤ 98, 0.1 ≤ α ≤ 40, and 58 ≤ β ≤ 97.9 are satisfied), when area proportions (%) of the Si material and the carbon material in an area of a field of view of each image of cross-sections of the negative electrode active material layer in a case where a plurality of arbitrary places is selected in a plane of the negative electrode active material layer are designated as S (%) and (100 - S) (%), respectively, a difference between the maximum value and the minimum value of S is within 5%; and wherein a variation in coating amount per unit area in the negative electrode active material layer at a plurality of selected sites in a case where a plurality of arbitrary places is selected in a plane of the negative electrode active material layer is within 5%.