Lithium secondary battery

Abstract

A lithium secondary battery 10 of the present invention is a secondary battery provided with a positive electrode 30 having a positive electrode active material layer 34 on a positive electrode collector 32, and a negative electrode 50 having a negative electrode active material layer 54 on a negative electrode collector 52. The positive electrode active material layer 34 contains a positive electrode active material capable of reversibly storing and releasing lithium ions. The negative electrode active material layer 54 contains a negative electrode active material made up of lamellar graphite that is bent so as to have an average number of bends f per particle of 0<f≦3, and an average aspect ratio of 1.8 or higher. In a cross-section perpendicular to the surface of the negative electrode collector 52, the negative electrode active material is oriented in such a manner that the perpendicularity defined as n2/n1, is 1 or greater, n1 being the number of negative electrode active material units such that 0°≦θn≦30°, and n2 being the number of negative electrode active material units such that 60°≦θn≦90°, where θn is the angle formed by a major axis of the negative electrode active material units with respect to the surface of the negative electrode collector 52.

Dependencies are inferred from the claim text.