Toyota Jidosha Kabushiki Kaisha

Kabushiki Kaisha Toyota Jidoshokki

Junpei Terashima

Masato Kamiya

Shinji Suzuki

Taira Saito

Ayumu Kamakura

Kazuma Abe

A non-aqueous electrolyte secondary battery includes a wound electrode body in which a first and a second separator, and a negative and a positive electrode body are stacked and wound. The wound electrode body has two R portions and is positioned in a flat portion. In a cross section orthogonal to a winding axis, when a distance from a bending end straight line to the winding starting end of the negative electrode body in a reference direction is denoted by A, a distance from the bending end straight line to the winding starting end of the positive electrode body in the reference direction is denoted by B, and X represents a distance from the bending end straight line to the winding end of the negative electrode body in the reference direction in the cross section is denoted by X, A, B, and X satisfy Condition: A&#x3c;B&#x3c;X.

Non-aqueous electrolyte secondary battery

A flat electrode body of a battery has a first-side curved end positioned on a first side of an electrode body width direction and a second-side curved end positioned on a second side. A positive electrode innermost curved portion of a positive electrode sheet is disposed inside the first-side curved end. When the dimension from a positive electrode connecting portion to the end on the first side of the electrode body is defined as a distance and the dimension from the positive electrode connecting portion to the end on the second side of the electrode body is defined as a distance, the positive electrode connecting portion being in the positive electrode protrusion wound portion and connected to a terminal connecting portion of a positive terminal member, the terminal connecting portion is connected to the positive electrode connecting portion at a position satisfying the condition Ha&#x2265;1.1Hb.

Battery

The present invention provides a lithium secondary battery having a positive electrode provided with a positive electrode active material formed of a lithium-manganese complex oxide represented by the general formulaLi(MnCoNi)MO&#x2003;&#x2003;(1)(where, a, b, and c are 0&#x3c;a&#x3c;0.65, 0&#x2266;b, and 0&#x2266;c, and x and y are 0&#x3c;x&#x3c;1.3 and 0&#x3c;y&#x3c;0.05), with the element M being an element that has a larger bond energy with oxygen than Mn, Co, or Ni.

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Nagoya, Japan

Junpei Terashima