NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

The present disclosure aims to, in a nonaqueous electrolyte secondary battery using a silicon compound as a negative electrode active material, suppress deformation of a negative electrode. A nonaqueous electrolyte secondary battery according to one example of an embodiment includes a winding type electrode body in which a positive electrode (11) and a negative electrode (12) are spirally wound with at least one separator interposed therebetween. In a negative electrode mixture layer (41), a silicon compound is contained as a negative electrode active material. A winding-start side end (42) of the negative electrode mixture layer (41) extends to a winding-start end side of the electrode body past a winding-start side end (32) of a positive electrode mixture layer (31). A length Y (mm) of a portion of the negative electrode mixture layer (41) extending from the winding-start side end (32) of the positive electrode mixture layer (31) and a rate X (percent by mass) of the silicon compound with respect to the total mass of the negative electrode active material satisfy a relationship of Y≥3X-15 (6≤X≤15).