Sanyo Electric Co., Ltd.

Akira Nishida

Yoshifumi Magari

Kazuaki Tamura

Atsutoshi Ako

Tomoyuki Yamada

Taiki Nonaka

Kentaro Tsukamoto

Kensuke Watanabe

A secondary battery provided with: a belt-like positive electrode plate having a plurality of positive electrode tabs; and a positive electrode current collector which is connected so that the plurality of positive electrode tabs are stacked, wherein the positive electrode plate has a positive electrode core body and a positive electrode active material layer formed on the positive electrode core bodies. At one edge side of the positive electrode plate where the plurality of positive electrode tabs are provided, one surface of the positive electrode core body has formed thereon a first protrusion that protrudes from said surface of the positive electrode core body in the thickness direction of the positive electrode core body, whereas the other surface of the positive electrode core body has no protrusion formed to protrude from said other surface of the positive electrode core body in the thickness direction of the positive electrode core body.

Secondary battery

A positive electrode plate that has a positive electrode active material layer formed on a positive electrode core, wherein the positive electrode core has, on an edge side, a thick portion which has a thickness that is greater than the thickness of a portion of the positive electrode core that has the positive electrode active material layer formed on both sides, and the positive electrode plate has a first region that extends into the thick portion from the portion of the positive electrode core that has the positive electrode active material layer formed on both sides and a second region that is positioned outside the first region in the thick portion. The average maximum diameter of the metal crystal grains that compose the first region is smaller than those of the second region.

Electrode plate and method for manufacturing same, and secondary battery and method for manufacturing same

The nonaqueous electrolyte secondary battery according to one embodiment includes a flat wound electrode body in which a positive plate and a negative plate are wound via a separator and characterized in that the positive plate has a positive core and a positive mixed material layer that is formed on both sides of the positive core, the positive mixed material layer includes a lithium metal composite oxide represented by general formula Li1+xMaO2+b (in the formula, x, a, and b satisfy the conditions x+a=1, −0.2<x≤0.2, and −0.1≤b≤0.1, and M includes Ni and Co and at least one element selected from the group consisting of Mn and Al), and the positive plate has a flexibility index of 15 to 19. Such a positive plate is capable of having a high packing density while suppressing cracks in the positive mixed material layer and buckling of the positive plate and the negative plate.

Method for manufacturing nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery

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Hyogo, Japan

Akira Nishida