JPH0430774Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention relates to a bobbin type non-aqueous electrolyte battery equipped with a positive electrode inner can.

<Prior art> In a bobbin type non-aqueous electrolyte battery such as a bobbin type lithium battery, a cylindrical negative electrode is inserted into the center of the positive electrode can.
This negative electrode is opposed to the positive electrode mixture placed outside through a separator, and a sealing gasket is sandwiched between the positive electrode can opening and the peripheral edge of the terminal plate provided in this opening. . Among these types of batteries, those with a high total battery height use a structure in which the sealing gasket is supported from below by an annular protrusion formed by constricting the opening of the battery can to prevent it from falling into the battery. However, for batteries with a relatively low total height, this configuration would result in a considerable reduction in the storage volume of the power generation element, so instead of this configuration, the inner periphery of the positive electrode can and the outer periphery of the positive electrode mixture A positive electrode inner can is provided between the positive electrode inner can and the positive electrode inner can, whose end on the positive electrode can opening side is bent inward, and the sealing gasket is supported from below by this bent end.

In a battery using such a positive electrode inner can, for example, a bobbin type lithium battery, as illustrated in FIG. 2, a positive electrode inner can 2, a positive electrode mixture 3,
While the lithium negative electrode 10 is sequentially housed through the separator 4, the other end of the lead terminal 6 for taking out current is fixed to the current collector attached to the inside of the lithium negative electrode by spot welding or the like. The terminal plate 7 was fixed to the terminal plate 7 by spot welding, etc., and then the terminal plate 7 was placed in the opening of the positive electrode can together with the sealing gasket 8 fitted around its periphery, and then the opening of the positive electrode can was caulked. Assembled in steps. In this case, if the lead terminal 6 is not long enough, it will be difficult to weld it to the current collector of the lithium negative electrode 10 or the terminal plate 7, so be sure to bend the lead terminal 6 when storing it during the above assembly. The state will be as follows.

<Problems to be Solved by the Invention> However, in a battery having such a structure, the lead terminal 6 is pressed into contact with the opening flange of the bent end 2a of the battery inner can 2 via the separator 4 due to the bending described above. will be done. Then, the burr of the lead terminal 6, that is, the thin jagged metal piece that remains at the cut end of the lead terminal 6 when the lead terminal 6 is cut, passes through the separator 4 and comes into contact with this opening flange, and furthermore, the lead terminal The bent part of 6 is separator 4
As a result, such as breaking and coming into direct contact with the opening flange part,
There was a problem in which a half-shot or shot occurred inside the battery, and if it was stored or used in this state, it would cause an abnormal voltage drop.

<Means for solving the problems> The bobbin type non-aqueous electrolyte battery of this invention has a hollow cylindrical positive electrode mixture 3 tightly attached to the inner peripheral surface of a positive electrode inner can 2 provided inside the positive electrode can 1. A cylindrical negative electrode 5 is placed in the hollow part of the positive electrode mixture 3 with a separator 4 in between, and the cylindrical negative electrode 5 and the inner surface of the terminal plate 7 provided in the opening of the positive electrode can 1 are connected. Electrical connection is made by the lead terminal 6, and this lead terminal 6
is bent and arranged between the cylindrical negative electrode 5 and the terminal plate 7, and the end of the positive electrode inner can 2 on the opening side of the positive electrode can 1 is bent inward, and this bent end 2a, in a bobbin type non-aqueous electrolyte battery having a structure that supports a sealing gasket 8 which is compressed between the opening of the positive electrode can 1 and the peripheral edge of the terminal plate 7, on the opening side of the positive electrode can 1, the cylinder The gist is that the upper end 5a of the shaped negative electrode 5 is provided to protrude closer to the terminal plate 7 than the opening flange of the bent end 2a of the positive electrode inner can 2. Note that the reference numerals immediately after the above-mentioned component names are for convenience to represent corresponding elements in the drawings, and therefore, the present invention is not limited to the descriptions in the drawings. The same applies to the next <effect> column.

<Function> In the bobbin type non-aqueous electrolyte battery having the configuration described in the above section <Means for solving the problems>,
With the separator 4 in between, the cylindrical negative electrode 5 covers the inside of the opening flange of the bent end 2a of the positive inner can 2, and the bent part of the lead terminal 6 is covered with this covering. Since the lead terminal 6 cannot reach the bent end 2a of the positive electrode inner can 2, the contact between the lead terminal 6 and the positive electrode inner can 2 is reliably prevented.

<Example> Next, an example in which this invention is applied to a bobbin type lithium battery will be described.

In Figure 1, inside a positive electrode can 1 made of stainless steel and having a bottomed cylindrical shape, there is a positive electrode inner can 2 made of stainless steel, an active material such as carbon fluoride or manganese dioxide, and a conductive agent, a binder, etc. A positive electrode mixture 3 press-molded into a hollow cylindrical shape after addition and kneading, a separator 4 made of polypropylene nonwoven fabric, and a cylindrical lithium negative electrode 5 are housed in this order. One end of a lead terminal 6 for taking out current is spot welded to a current collector such as a punched metal attached to the inside of the lithium negative electrode 5, and the other end of this lead terminal 6 is a terminal. The wires are connected to the inner surface of the plate 7 by spot welding. A synthetic resin sealing gasket 8 placed on the bent end 2a of the positive inner can 2 is clamped between the positive electrode can opening and the peripheral edge of the terminal plate.

In the battery having the above configuration, in the state after the battery is assembled as shown in FIG. It is located nearby.

The battery of this embodiment having such a configuration is assembled in the same manner as the conventional battery described above. At that time, even if the bent lead terminal 6 is pressed toward the opening flange of the bent end 2a, the upper end 5a of the lithium negative electrode 5 pushes the lead terminal 6 toward the bent end of the positive electrode inner can 2. 2a, and this prevents the opening flange from coming into contact with the lead terminal 6 or its burr, thereby eliminating the occurrence of shoots or half-shots in the battery as in the conventional case.

<Effects of the invention> According to the bobbin-type non-aqueous electrolyte battery of this invention constructed as described above, contact between the lead terminal and the positive electrode inner can during and after battery assembly is prevented, thereby preventing damage inside the battery. As a result of preventing half-shot or shot, abnormal voltage drop caused by the contact during storage or use can be eliminated, and the performance and reliability of the battery can be improved. In addition, since half-shot or short-shot due to bent lead terminals can be reliably prevented, the bending position of the lead plate can be freely selected, making assembly easier, which also has the advantage of facilitating battery manufacture.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional example. 1... Positive electrode can, 2... Positive electrode inner can, 3... Positive electrode mixture, 4... Separator, 5, 10... Lithium negative electrode, 6... Lead terminal, 8... Sealing gasket.

Claims (1)

[Claim for Utility Model Registration] A hollow cylindrical positive electrode mixture is placed in close contact with the inner peripheral surface of a positive inner can provided inside the positive electrode can, and a cylindrical positive electrode mixture is placed in the hollow part of the positive electrode mixture through a separator. A negative electrode is positioned and arranged, and this cylindrical negative electrode and the inner surface of the terminal plate provided in the opening of the positive electrode can are electrically connected by a lead terminal, and this lead terminal is connected to the cylindrical negative electrode and the terminal plate. and a plate, and further bending the end of the positive electrode inner can on the positive electrode can opening side,
In a bobbin type non-aqueous electrolyte battery having a structure in which the bent end portion supports a sealing gasket which is compressed between the positive electrode can opening and the terminal plate peripheral portion, the tube is arranged on the positive electrode can opening side. 1. A bobbin type non-aqueous electrolyte battery, characterized in that the upper end of the shaped negative electrode projects closer to the terminal plate than the opening flange of the bent end of the positive electrode inner can.