Cylindrical battery

Abstract

In the cylindrical battery (10), a point (P) is defined as the position of the positive electrode (11) that overlaps with the positive electrode start end (11x) in the radial direction of the electrode body (14) and is located at the center of the width direction of the positive electrode (11) that is one turn outside the positive electrode start end (11x). A circle passing through point (P) with the winding center (Z) as the center is defined as a circle (α1). A circle (α2) is defined as the circle passing through the first point that moves 3° from the center of the width direction of the positive electrode (11) towards the winding start side, the second point that moves 3° from the point (P) towards the winding end side, and the third point (P). In the case where the curvature R2 of circle (α2) is less than or equal to the curvature R1 of circle (α1), the ratio (R2 / R1) is less than or equal to 0.90.

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