Patent ID: 8986874
Filing Date: 2015-03-24
Classification: H01M,Y02E,Y02P,Y10T

Abstract:
1. A prismatic cell comprising: a wound electrode body that includes a positive electrode sheet having a first metal foil on which a positive active material has been applied, a negative electrode sheet having a second metal foil on which a negative active material has been applied, and a separator intervening between the positive and negative electrode sheets, wherein the positive electrode sheet, the negative electrode sheet and the separator are wound around a winding axis into a flat shape, and a part of the first metal foil is applied with no positive active material at one end of the wound electrode body in a direction of the winding axis to constitute a first non-applied part of the wound electrode body, and a part of the second metal foil is applied with no negative active material at another end of the wound electrode body in the direction of the winding axis to constitute a second non-applied part of the wound electrode body; a flat container having a flat shape in cross-section, in which the wound electrode body is accommodated, the container having an opening, first opposite sides and second opposite sides and a bottom, with the first opposite sides being shorter than the second opposite sides; a lid that seals the opening of the container; positive and negative external terminals provided on the lid; a positive electrode collector member that is connected to the first non-applied part of the wound electrode body, wherein the positive electrode collector member includes a horizontal flat plate opposite to a back surface of the lid, a vertical flat plate that is bent from the horizontal flat plate toward the bottom of the container and a pair of positive electrode connector leaves provided at both sides of a lower end of the vertical flat plate, the pair of the positive electrode connector leaves protruding from both sides of a lower end of the vertical flat plate, being inclined such that a gap therebetween is decreasing as the positive electrode connector leaves extend from one of the first opposite sides toward an inside of the container, extending toward the bottom of the container, and being respectively connected to an outer peripheral surface of the first non-applied part of the wound electrode body; and a negative electrode collector member that is connected to the second non-applied part of the wound electrode body, wherein the negative electrode collector member includes a horizontal flat plate opposite to a back surface of the lid, a vertical flat plate that is bent from the horizontal flat plate toward the bottom of the container and a pair of negative electrode connector leaves provided at both sides of a lower end of the vertical flat plate, the pair of the negative electrode connector leaves protruding from both sides of a lower end of the vertical flat plate, being inclined such that a gap therebetween is decreasing as the negative electrode connector leaves extend from one of the first opposite sides toward an inside of the container, extending toward the bottom of the container, and being respectively connected to an outer peripheral surface of the second non-applied part of the wound electrode body; the positive electrode sheet has the first non-applied part of the wound electrode body, and the first non-applied part has two positive electrode sheet laminates that are present as two separated laminates with respect to each other such that the two separated laminates are expanded outwardly, and the positive electrode sheet laminates have a peripheral surface that is situated in the external boundary of the positive electrode sheet laminate, and the pair of the positive electrode connector leaves are respectively connected to portions of the outer peripheral surfaces that oppose an inner surface of the flat container; the negative electrode sheet has the second non-applied part of the wound electrode body, and the second non-applied part has two negative electrode sheet laminates that are present as two separated laminates with respect to each other such that the two separated laminates are expanded outwardly, and the negative electrode sheet laminates have a peripheral surface that is situated in the external boundary of the negative electrode sheet laminate, and the pair of the negative electrode connector leaves are respectively connected to portions of the outer peripheral surfaces that oppose the inner surface of the flat container; the pair of the positive electrode connector leaves protruding from the both sides of the vertical flat plate directly and extending toward inside to the flat container; and the pair of the negative electrode connector leaves protruding from the both sides of the vertical flat plate directly and extending toward inside to the flat container.