JP2012099264A5

JP2012099264A5 -

Info

Publication number: JP2012099264A5
Application number: JP2010244114A
Authority: JP
Filing date: 2010-10-29
Publication date: 2013-09-19

Description

本発明による二次電池は、活物質が両面に塗布されたシート状の正負極板をセパレータを介在させて扁平形状に捲回され、最外周面が前記セパレータで覆われた電極群と、開口部が設けられた電池缶と、前記開口部を覆う電池蓋と、前記電池蓋に固定され、前記正負極板とそれぞれ正負極接続板により電気的に接続されている正負極外部端子とを有し、前記電極群は、前記電池缶の表裏に広がる幅広面と対向する一対の平坦部と、一対の平坦部の両端で正負極板が折り返される折り返し部とを有し、前記電極群は前記折り返し部が前記電池缶の底面と対向して前記電池缶の中に配置され、前記セパレータの巻き終わり端部は、その端縁が前記電池缶の底面の方向とは異なる方向を向いて固着されていることを特徴とする。 The secondary battery according to the present invention includes an electrode group in which a sheet-like positive and negative electrode plate coated with an active material on both sides is wound into a flat shape with a separator interposed therebetween, and an electrode group whose outermost peripheral surface is covered with the separator Yes and battery can section is provided, a battery lid for covering the opening, secured to said battery cover, a negative electrode external terminal which is electrically connected by the positive and negative electrode plates and each negative electrode connecting plate The electrode group includes a pair of flat portions facing the wide surfaces spreading on the front and back of the battery can, and a folded portion where the positive and negative electrode plates are folded at both ends of the pair of flat portions. The folded portion is disposed in the battery can so as to face the bottom surface of the battery can, and the end of the winding end of the separator is fixed in a direction different from the direction of the bottom surface of the battery can. It is characterized by.

Claims

An electrode group in which a sheet-like positive and negative electrode plate coated with an active material on both sides is wound into a flat shape with a separator interposed therebetween, and an outermost peripheral surface is covered with the separator,
A battery can provided with an opening ;
A battery lid covering the opening ;
The positive and negative electrode external terminals fixed to the battery cover and electrically connected by the positive and negative electrode plates and the positive and negative electrode connection plates, respectively,
The electrode group has a pair of flat portions facing the wide surface spreading on the front and back of the battery can, and a folded portion where the positive and negative electrode plates are folded at both ends of the pair of flat portions,
The electrode group is disposed in the battery can with the folded portion facing the bottom surface of the battery can,
The secondary battery is characterized in that the end of winding end of the separator is fixed with its edge facing in a direction different from the direction of the bottom surface of the battery can.

The secondary battery according to claim 1,
The secondary battery is characterized in that an edge of the separator is located in a flat portion region of the electrode group.

The secondary battery according to claim 1 or 2,
The secondary battery is characterized in that an edge of the separator faces a back surface direction of the battery lid.

The secondary battery according to claim 1,
The secondary battery is characterized in that an edge of the separator is located in a surface region having a curvature of a folded portion of the electrode group.

The secondary battery according to any one of claims 1 to 4,
The secondary battery is characterized in that an edge of the separator is fixed to a wound immediate lower layer in a part or the entire width in the width direction.

The secondary battery according to any one of claims 1 to 4,
The secondary battery is characterized in that the edge and the immediately lower winding layer are fixed by an adhesive tape.

The secondary battery according to any one of claims 1 to 4,
The secondary battery according to claim 1, wherein the edge and the immediately lower layer of the winding are fixed by an adhesive.

The secondary battery according to any one of claims 1 to 4,
The secondary battery is characterized in that the edge and the immediately lower winding layer are fixed by thermocompression bonding.

A sheet-like positive and negative electrode plate coated with an active material on both sides is wound while interposing a separator,
A first step of producing an electrode group whose outermost peripheral surface is covered with the separator;
A second step of connecting the positive and negative electrode connection plates respectively connected to the positive and negative electrode external terminals installed on the battery lid and the positive and negative electrode plates;
A third step in which the electrode group to which the positive and negative electrode connection plates are connected is inserted into the flat rectangular parallelepiped battery can by inserting the folded portion toward the bottom surface of the battery can from the opening; and
A fourth step of sealing the opening with the battery lid after the third step;
The second step includes a fifth step of defining the posture and form of the electrode group so that the edge of the separator on the outermost peripheral surface of the electrode group faces the back surface of the battery lid. Manufacturing method.

In the manufacturing method of the rechargeable battery according to claim 9,
The first step includes
A sixth step of measuring the winding length of the positive and negative electrode plates and the separator;
And a seventh step of determining a position for cutting the separator based on the winding length of the separator measured in the sixth step,
The manufacturing method of the secondary battery, wherein the seventh step is determined to have such a length that an edge of the separator is positioned on a flat portion of the electrode group.