JPH0338830Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to an electric double layer capacitor in which a coin-shaped cell, which is a capacitance element, is inserted into an exterior metal case. This invention relates to means for preventing rotation of an electrode unit disposed in an opening of the electrode unit.

[Conventional example]

Electric double layer capacitors are mainly used as memory backup capacitors, but since the rated voltage of a single cell is low, multiple cells are stacked to obtain a high voltage. That is, a predetermined number of cells are inserted into a cylindrical exterior metal case with a bottom, and an electrode unit consisting of a pair of electrode plates both having lead terminals and an electrically insulating plate interposed between them is arranged inside the case opening. After making electrical contact between the uppermost cell and one electrode plate, the case opening is caulked inward and its edge is mechanically and electrically joined to the other electrode plate. A desired voltage is obtained through the lead terminals.

[Problem that the invention attempts to solve]

When caulking the opening of the exterior metal case, increasing the caulking will improve the contact between the cells, between the cells and the case, and between the cells and the electrode plates, which will reduce the series resistance of the electric double layer capacitor itself. However, if the caulking pressure is too strong, there is a risk that the electrolyte sealed in the cell will leak and its properties will deteriorate.

Therefore, the case opening is caulked with enough force to prevent electrolyte leakage, but according to this method, when external force is applied, the electrode plate rotates inside the case opening, causing damage to the case itself or the case itself. Another drawback is that the relationship with the polarity display mark displayed on the sleeve is inconsistent.

This invention aims to solve the above-mentioned conventional drawbacks.

[Means for solving problems]

In order to achieve the above object, in this invention, a pair of parallel slits are provided in the opening of the exterior metal case along the axial direction to form a bendable tongue piece, and a bendable tongue piece is formed in the opening of the case. An engagement groove that engages with the tongue piece is provided on the side of the electrode unit to be placed, and after the electrode unit is placed in the case opening, the tongue piece is bent and engaged in the engagement groove.

〔Example〕

Hereinafter, one embodiment of this invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, this electric double layer capacitor includes a cylindrical exterior metal case 1 with a bottom. A plurality of coin-shaped cells 2, three in this embodiment, are inserted into the exterior metal case 1. A protrusion 1a is formed at the bottom of the exterior metal case 1 for making good electrical contact with the lowest cell 2. Furthermore, a sleeve 3 made of a synthetic resin film is placed around the three stacked cells 2 in order to electrically insulate them from the exterior metal case 1.

An electrode unit 4 for extracting voltage from the stack of cells 2 is arranged in the opening of the exterior metal case 1. This electrode unit 4 has a first electrode plate 5 having a lead terminal 5a long enough to protrude from the case opening, and a lead terminal 6a long enough to protrude from the case opening similarly to the second electrode plate 6. In this example, the lower first electrode plate 5 is arranged so as to be in contact with the electrode surface of the uppermost cell 2. According to this embodiment, the upper second electrode plate 6 has two grooves 6b, 6 cut in its diametrical direction from opposite edges.
c are formed, and the upper surface of the electrically insulating plate 7 has raised portions 7a, which engage with the grooves 6b, 6c.
7b is provided, so that the two are combined so that no relative rotational deviation occurs. Note that the first electrode plate 5 is formed to have a smaller diameter than the electrically insulating plate 7 so as not to come into contact with the exterior metal case 1, and its lead terminal 5a is bored in a raised portion 7a of the electrically insulating plate 7. It is drawn out through the small hole 7c.

The opening of the exterior metal case 1 has at least one
In this embodiment, two bendable tongues 8, 8 are provided with an interval of 180°. The tongue piece 8 is formed by cutting a pair of slits 8a, 8a parallel to the axial direction of the case 1 to a predetermined depth from the edge of the opening. On the other hand, a pair of engagement grooves 9, 9 are provided, for example, extending from the second electrode plate 6 to the electrically insulating plate 7 of the electrode unit 4, to engage with the tongue pieces 8, 8. That is, after the electrode unit 4 is placed in the opening of the case 1, the tongue pieces 8, 8 are bent inward and engaged with the engagement grooves 9, 9, so that the electrode unit 4 is locked in a non-rotatable manner. Ru. Thereafter, the opening of the case 1 is caulked inward by a caulking machine (not shown), and the opening edge 1b is mechanically and electrically joined to the second electrode plate 6. As a result, one electrode of the laminate of the cell 2 is drawn out through the exterior metal case 1, the second electrode plate 6 and its lead terminal 6a, and the other electrode is drawn out through the first electrode plate 5 and its lead terminal. 5a to the outside.

Note that the engagement groove 9 in the electrical insulating plate 7 is connected to the tongue piece 8.
In order to prevent electrical contact between the electrode plate 5 and the first electrode plate 5,
It is a groove with a bottom. Further, unlike the above embodiment, an engagement groove that engages with the tongue pieces 8, 8 may be provided only in the second electrode plate 6.

〔effect〕

As is clear from the description of the embodiments described above, according to this invention, a bendable tongue piece 8 is formed at the opening of the exterior metal case 1, and the tongue piece 8 is engaged with the electrode unit 4 side. After the electrode unit 4 is placed in the opening of the case 1, the tongue piece 8 is bent and engaged with the engagement groove 9, thereby reducing the caulking force at the case opening. Even if the cell 2 is folded to the extent that electrolyte leakage does not occur, the electrode plates 5 and 6 will not rotate due to impact force during product transportation, and the electrode plates 5 and 6 will not be misaligned with the polarity display mark. A double layer capacitor is obtained.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of an embodiment of an electric double layer capacitor constructed according to this invention;
FIG. 2 is a sectional view of the same embodiment in an assembled state. In the figure, 1 is an exterior metal case, 2 is a cell, 3 is a sleeve, 4 is an electrode unit, 5 is a first electrode plate,
6 is a second electrode plate, 5a, 6a are lead terminals, 7
8 is an electrically insulating plate, 8 is a tongue piece, and 9 is an engagement groove.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A predetermined number of coin-shaped cells, which are capacitive elements, are inserted into a bottomed cylindrical exterior metal case, and a lead protrudes outward from the opening of the exterior metal case. An electrode unit in which first and second electrode plates each having a terminal are stacked with an electrically insulating plate in between is inserted into the opening of the exterior metal case so that the first electrode plate is in electrical contact with the cell. an electric double layer capacitor in which the opening of the exterior metal case is crimped inward and the edge thereof is mechanically and electrically connected to the second electrode plate; A bendable tongue piece is formed by providing a pair of parallel slits in the axial direction of the electrode unit, and an engagement groove that can be engaged with the tongue piece is provided on the electrode unit side. The electric double layer capacitor is characterized in that the tongue piece is bent inward and engaged with the engagement groove after the tongue piece is placed in the case opening. (2) The electric double layer capacitor according to claim (1), wherein the engaging groove is formed from the second electrode plate to the electrically insulating plate. (3) The electric double layer capacitor according to claim (1), wherein the engaging groove is formed in the second electrode plate. (4) In claim (1) or (2) of utility model registration, it is stated that the second electrode plate and the electrical insulating plate are connected so that no relative rotational deviation occurs between them. Features of electric double layer capacitors. (5) In claim (1) for utility model registration, the lead terminal of the first electrode plate includes a small hole formed in the electrical insulation plate and a groove portion formed in the second electrode plate. An electric double layer capacitor, characterized in that the capacitor is drawn out to the outside of the exterior metal case through the capacitor.