JP2014022436A - Electronic component and electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance productivity by sealing a concave container more reliably with a sealing plate.SOLUTION: A ramp 3b larger than a concave container 2 is formed partially or entirely on the outer periphery of a sealing plate 3. Positioning is facilitated when setting the sealing plate 3 in the concave container 2 before welding, by inclining the ramp 3b to the concave container 2 side. Furthermore, positional deviation can be prevented, even if the sealing plate 3 is brought into a state floating from the concave container 2 by electrodes 5, 6 or a separator 7.

Description

  The present invention relates to an electronic component and an electronic device, for example, an electrochemical cell such as an electric double layer capacitor and a nonaqueous electrolyte battery.

An electric double layer capacitor is a device that stores electricity by polarizing ions in an electrolyte and supplies electric power by discharging the ions.
With this storage / discharge function, the electric double layer capacitor is used, for example, for a clock function of an electronic device, a backup power source such as a semiconductor memory, and a standby power source of an electronic device such as a microcomputer or an IC memory.
In particular, a surface-mountable electric double layer capacitor can be reduced in size and thickness, and is suitable for a thin portable terminal.
In order to meet such a demand for downsizing and thinning, in Patent Document 1 below, as described below, a polarizing electrode and an electrolyte are housed in a container having a recess, and the opening is sealed with a sealing plate. Stopped electric double layer capacitors have been proposed.

FIG. 9 is a side sectional view of a conventional electric double layer capacitor 100.
A metal layer 111 is provided on the bottom surface of the ceramic concave container 102 in which the recess 113 is formed, and the positive electrode 106 is joined to the upper surface of the metal layer 111. The metal layer 111 penetrates the concave container 102 and is electrically connected to the positive electrode terminal 112 on the bottom surface of the concave container 102, so that the positive electrode 106 is electrically connected to the positive electrode terminal 112 through the metal layer 111. Connected to.
Further, the sealing plate 103 is bonded to the opening of the recess 113 by the metal bonding metal layer 108 to seal the recess 113.
A metal layer 115 that functions as a current collector is formed on the lower surface of the sealing plate 103, and the negative electrode 105 is bonded to the surface of the metal layer 115.
A metal layer 109 is formed on a side surface of the concave container 102 to connect the bonding metal layer 108 and the negative electrode terminal 110 on the bottom surface of the concave container 102.
The negative electrode 105 is electrically connected to the negative electrode terminal 110 through the metal layer 115, the bonding metal layer 108, and the metal layer 109.

A separator 107 that prevents these short circuits is provided between the negative electrode 105 and the positive electrode 106, and the negative electrode 105, the positive electrode 106, and the separator 107 are impregnated with an electrolyte.
The electric double layer capacitor 100 stores electricity when a voltage is applied to the negative electrode terminal 110 and the positive electrode terminal 112, and discharges the stored electric charge to supply power to the maintenance of a clock function, a memory, or the like.

  Thus, in the conventional electronic component, in order to prevent the electrolyte from leaking to the outside, it is necessary to seal the concave container 102 with the sealing plate 103, and the bonding metal layer formed on the concave end (side surface) of the concave container 102. 108 and the sealing plate 103 are sealed by laser welding or parallel seam welding.

However, since the conventional sealing plate 103 is flat as shown in FIG. 9, it is difficult to position it with respect to the concave container 102.
And since it is planar, it shifted | deviated easily, and there existed a case where sealing by welding could not fully be performed.

Further, the sealing plate 103 has a function of pressing the positive electrode 106, the separator 107, and the negative electrode 105 together with a function of sealing.
That is, the thicknesses of the electrodes 105 and 106 and the separator 107 before welding are formed larger than the depth of the recess 113, and the electrodes and separators are pressed by pressing the electrodes and the like in the thickness direction with the welded sealing plate 103. Is prevented from moving.
For this reason, the sealing plate 103 before welding may be in a state of being lifted from the concave container 102 due to the thickness of an electrode or the like, and there is a possibility that the sealing plate 103 is displaced during movement.

Further, in parallel seam welding, energization is performed in a state of being sandwiched from both sides (left and right sides in FIG. 9) of the sealing plate 103 by a pair of truncated cone-shaped electrode rolls. For this reason, since the electrode roll and the sealing plate 103 are in a point contact state, it is necessary to flow a large current in order to ensure sufficient heat generation by energization.
However, when a large current is applied, the overheated state occurs, and cracks may occur in the concave container.

  Such a problem occurs not only in the electric double layer capacitor but also in an electrochemical cell constituting another type of electronic component such as a nonaqueous electrolyte battery.

JP 2001-216852 A

  An object of the present invention is to provide an electronic component such as an electrochemical cell that can more reliably seal a concave container with a sealing plate, and to increase the productivity of the electronic component.

(1) In invention of Claim 1, formed in the exterior of the concave container, the sealing board which seals the said concave container, the 1st internal electrode arrange | positioned in the said concave container, and the said concave container A first external electrode; a first connecting means for electrically connecting the first internal electrode and the first external electrode; and a first gap between the first internal electrode and the first internal electrode. A second internal electrode; a second external electrode formed outside the concave container; and a second connection means for electrically connecting the second internal electrode and the second external electrode; The plate is provided with an inclined portion that is formed larger than at least the welded portion located inside the concave container and is inclined toward the concave container side.
(2) In the invention according to claim 2, the concave container and the sealing plate are joined by seam welding through an annular joining metal layer. I will provide a.
(3) The invention according to claim 3 provides the electronic component according to claim 1 or 2, wherein the inclined portion is formed over the entire circumference.
(4) In the invention according to claim 4, the seam welding is performed by energizing the sealing plate with a pair of truncated cone-shaped electrode rolls, and the inclined portion of the sealing plate is The electronic component according to claim 3, wherein the electronic component is formed at the same angle as an inclination angle of the electrode roll surface.
(5) The invention according to claim 5, wherein the inclined portion of the sealing plate is formed by a pressing force by the pair of electrode rolls during welding by the pair of electrode rolls. An electronic component according to claim 4 is provided.
(6) In the invention described in claim 6, the sealing plate has a concave portion in the concave container side direction or in the opposite direction formed on a surface facing the concave section formed in the concave container. An electronic component according to any one of claims 1 to 5 is provided.
(7) In the invention according to claim 7, the sealing plate is made of stainless steel, and the electronic component according to any one of claims 1 to 6 I will provide a.
(8) In the invention according to claim 8, the electronic component according to any one of claims 1 to 7, the power storage means for storing power in the electronic component, and a predetermined function There is provided an electronic apparatus comprising: another electronic component to be exhibited; and power supply means for supplying electric power to the other electronic component using the stored charge.

According to the present invention, positioning of the sealing plate is facilitated by the configuration including the inclined portion that is formed larger than the concave container and inclined toward the concave container at least at a part of the outer periphery of the sealing plate.
Moreover, since it is possible to prevent misalignment before welding by the inclined portion, it is possible to more reliably perform sealing with the sealing plate.
Furthermore, by forming the inclined part over the entire circumference and forming it at the same angle as the inclination angle of the electrode roll surface for seam welding, the contact area between the inclined part and the electrode can be increased, and the current can be reduced. It becomes possible to prevent cracking of the concave container due to overheating.

It is a figure for demonstrating the electric double layer capacitor which concerns on embodiment. It is explanatory drawing showing the cross-sectional shape of the inclination part in a sealing board. It is explanatory drawing showing the modification about the shape of the sealing plane part in a sealing board. It is explanatory drawing showing the other modification about the shape of the sealing plane part in a sealing board. It is explanatory drawing showing the planar shape of the inclination part in a sealing board. It is explanatory drawing showing the state which brazes a sealing board to a concave container with a joining metal layer by parallel seam welding. It represents the contact state between the electrode roll and the sealing plate. It is explanatory drawing showing the welding procedure with respect to the joining metal layer 8, and a welding state. It is a figure for demonstrating the conventional electric double layer capacitor.

(1) Outline of Embodiment An inclined portion larger than the concave container is formed on a part or the entire periphery of the outer periphery of the sealing plate. The sealing plate including the inclined portion is formed by forming and punching by pressing.
By inclining the inclined portion toward the concave container, positioning when the sealing plate is set in the concave container before welding is facilitated.
Further, even if the sealing plate is floated with respect to the concave container by the electrode or the separator, the positional deviation is prevented by the inclined portion.

  The shape of the sealing plate excluding the inclined portion is a shape corresponding to the concave container. In the case where the concave container is square, inclined portions are formed at least on two adjacent sides of the sealing plate, but it is more preferable for positioning to be formed on four sides. In the case where the concave container is circular or elliptical, inclined portions are formed at two positions, preferably at three or more positions at least at a predetermined interval of the sealing plate.

The sealing plate is formed by bonding an annular bonding metal layer to the upper surface of the open side (sealing plate side) of the concave container in which the concave portion is formed, and welding the bonding metal layer and the sealing plate. It is connected to the concave container through the bonding metal layer, and the concave container is sealed.
Welding is by seam welding in addition to laser welding.
The seam welding is performed while energizing at a predetermined interval (time or distance) while sandwiching from both sides of the sealing plate by a pair of electrode rolls having a truncated cone shape and rotating the electrode rolls.
At this time, since the inclined portion has the same inclination angle as the inclination of the electrode roll, the contact area between the sealing plate and the electrode roll can be increased. Therefore, in the portion where the inclined portion is formed, a small amount of current is applied. be able to.
In particular, by forming the inclined portion on the entire periphery of the sealing plate, the entire periphery can be reliably welded with a low current, and cracks due to heat of the concave container can be avoided.

Further, a flat sealing plate may be prepared, and the inclined portion may be inclined by a pressing force by an electrode roll at the time of seam welding. In other words, the inclined portion may be formed while performing seam welding. A flat sealing plate having a portion that becomes an inclined portion after welding is used.
In this case, the positioning is the same as in the prior art, but the contact area between the electrode roll and the sealing plate can be increased.
Note that the four corners or the like may be inclined in advance for positioning.
For the material of the sealing plate, metal such as Kovar (Co: 17, Ni: 29, Fe: 54 ratio) or stainless steel (SUS) is used. When forming an inclination, it is preferable to use stainless steel. By setting the thickness of the stainless steel in the range of 10 μm to 30 μm, preferably about 20 μm, it becomes possible to reduce the heating amount during seam welding or laser welding.

  By providing the sealing plate with an inclined portion that has been inclined in advance, the parts feeder can be used to select the front and back and boost the parts, thereby increasing the production efficiency. This is particularly effective when the small sealing plate is made of thin stainless steel.

(2) Details of Embodiment The electrochemical cell constituting the electronic component of the present embodiment will be described with reference to the drawings by taking an electric double layer capacitor as an example.
In addition, since each drawing to be used is displayed larger than other portions in order to clarify the portion to be explained, it is different from the actual size ratio.
FIG. 1A is a side sectional view of the electric double layer capacitor 1 according to the embodiment, and FIG. 1B is a plan view.
As shown in FIG. 1, the electric double layer capacitor 1 has a rectangular parallelepiped shape, and the size is, for example, a rectangular parallelepiped shape having a height of 1 mm or less, a length of about 2.5 mm × a width of about 3.2 mm, It has a rectangular parallelepiped shape with a height of 1 mm or less and a length of about 2.2 mm × width of about 2.9 mm.
In addition, the external shape of other electrochemical cells including the electric double layer capacitor 1 can be circular or elliptical as viewed from above. In this case, each part such as the concave portion 13, the electrodes 5, 6 and the separator 7 described as a square may be circular or elliptical, or may be square.

Moreover, although embodiment demonstrates the structure of the electronic component illustrated in FIG. 1, about shapes and structures other than the shape (especially inclination part 3b) of the sealing plate 3 which is the characteristic part of this embodiment, It can be configured.
For example, the concave container having the configuration shown in FIG. 9 or both electrodes 105 and 106, both terminals 110 and 112, both electrodes, and the electrodes 105 and 106 and both terminals 110 and 120 are electrically connected (metal layer 109, 111 etc.) may be adopted.

As shown in FIG. 1, the electric double layer capacitor 1 of this embodiment includes a concave container 2 having a concave portion 13, a sealing plate 3 having a metal layer 15 formed on the lower surface, an electrode 5 used as a negative electrode, Electrode 6 used as a positive electrode, separator 7, annular bonding metal layer 8, metal layer 11, current collector 18 a, through electrode 21, through electrode 22, terminal 10, terminal 12, and electrodes 5, 6 and separator 7 An electrolyte (not shown) or the like impregnated in is used.
The terminals 10 and 12 are terminals for surface mounting. In the following description, the terminals 10 and 12 are referred to as the downward direction, and the sealing plate 3 side is referred to as the upward direction.
In FIG. 1A, a gap is illustrated between the electrode 5, the separator 7 and the electrode 6 so that the joining relationship of the members can be easily understood. However, these members may be packed in the recess 13 without any gap. .

In the present embodiment, the electrode 5 and the electrode 6 function as a first internal electrode and a second internal electrode, respectively, and the terminal 10 and the terminal 12 function as a first external electrode and a second external electrode, respectively.
Further, the current collector 18b, the metal layer 15 (and the sealing plate 3), the bonding metal layer 8, the metal layer 9, and the through electrode 21 function as a first connection means for electrically connecting the electrode 5 and the terminal 10. Yes.
The current collector 18 a, the metal layer 11, and the through electrode 22 function as second connection means for electrically connecting the electrode 6 and the terminal 12.

As shown in FIG. 1 (a), the sealing plate 3 is formed on the outer peripheral surface of the sealing flat surface portion 3a and the sealing flat surface portion 3a that forms a hollow portion for accommodating the electrodes 5, 6 and the like together with the concave portion 13 of the concave container 2. And an inclined portion 3b to be formed.
The sealing flat surface portion 3 a is a portion facing the concave container 2 and is formed in the same area as the outer periphery of the opposing concave container 2, but is an annular shape formed slightly smaller than the outer periphery of the concave container 2. What is necessary is just an area more than the outer periphery of the joining metal layer 8.
The inclined portion 3 b is formed so as to extend from the outer peripheral edge of the bonding metal layer 8.
For example, when the outer dimensions of the concave container 2 are 2.5 mm in length × 3.2 mm in width, the outer dimensions of the bonding metal layer 8 are 2.2 mm in length × 2.9 mm in width and are annular with a width of 0.25 mm. For this reason, the outer periphery of the joining metal layer 8 is located 0.3 mm inside over the entire outer periphery of the concave container 2.
On the other hand, the length in the extending direction of the inclined portion 3b of the sealing plate 3, that is, the length from the outer peripheral edge of the bonding metal layer 8 to the extended end of the inclined portion 3b is selected according to the material of the sealing plate 3. The thickness of the sealing plate 3 is preferably about the same. For example, when a Kovar having a thickness of 0.1 mm is used as the sealing plate 3, the length in the extending direction of the inclined portion 3 b is about 0.1 mm, and the length in the extending direction when SUS having a thickness of 20 μm is used. The thickness is about 20 μm.
As a result, the outward extending end of the inclined portion 3b of the sealing plate is located between the outer periphery of the bonding metal layer 8 and the outer periphery of the concave container 2, and the inclined portion 3b protrudes outside the concave container 2. Absent.

The inclined portion 3b of the sealing plate 3 is inclined toward the concave container 2 by being bent at the boundary portion with the sealing flat surface portion 3a.
The sealing plate 3 can be easily positioned with respect to the concave container 3 (joining metal layer 8) by the inclination of the inclined portion 3b.
Details of the width and shape of the inclined portion 3b will be described later.

The sealing plate 3 is made of an alloy such as Kovar or SUS foil. The thickness of the sealing plate 3 is about 0.1 mm when Kovar is used, and about 20 μm when SUS is used.
A metal layer 15 is formed on the sealing plate 3 by nickel plating over the entire surface on the concave container 2 side. Since the metal layer 15 is formed to satisfactorily bond the sealing plate 3 to the bonding metal layer 8, it is not always necessary to form the entire surface of the sealing plate 3 on the concave container side. You may make it form the metal layer 15 cyclically | annularly by the predetermined width in the part corresponding to the cyclic | annular joining metal layer 8, ie, the outer peripheral side of the sealing board 3. FIG.
A current collector 18b (second current collector) using carbon as a conductive material is formed on the upper surface (lower side in the drawing) of the metal layer 15, and an electrode 5 (second electrode) used as a negative electrode on the upper surface. ) Is fixed.
In addition, about the material and formation of the electrical power collector 18b and the electrode 5, since it is the same as that of the electrical power collector 18a electrode 6 mentioned later, it abbreviate | omits.

The sealing plate 3 to which the electrode 5 is fixed by the current collector 18 b is physically and electrically connected to the opening of the recess 13 by brazing the metal layer 15 to the bonding metal layer 8. It is joined.
The brazing is dissolved by heating the sealing plate 3 while applying pressure, and the sealing plate 3 and the concave container 2 are joined.
More specifically, it is possible to use parallel seam welding in which the electrode roll is brought into contact with the edge of the sealing plate 3 with an appropriate pressure and is rotated while being energized. The joining metal layer 8 is heated by the contact resistance, and pressurization and heating are performed. The joining metal layer 8 is melted and fused with the metal layer 15 by the heating, and the recess 13 is sealed by the sealing plate 3.
In addition to parallel seam welding, heat welding by laser is also possible.

When performing parallel seam welding, it is desirable to select a material with good compatibility between the bonding metal layer 8 and the sealing plate 3. For example, when electrolytic nickel or electroless nickel is used for the bonding metal layer 8, the sealing plate 3 is , Kovar with electrolytic nickel or electroless nickel is used.
Or, conversely, when electrolytic nickel is used for the bonding metal layer 8, the sealing plate 3 is obtained by applying electroless nickel to Kovar. Thereby, it is not necessary to raise the welding power more than necessary. Furthermore, when performing electroless nickel, various reducing agents can be used. Examples include dimethylamine borane, hypophosphorous acid, hydrazine, sodium borohydride and the like. Here, when the nickel used for plating is melted as the brazing material, it is desirable that the melting point of nickel is lower. Therefore, by using hypophosphorous acid as a reducing agent during plating, when the chemical composition of the finished plating is “Ni: 90% -96%, P: 4% -10%”, boron Compared to the case of containing, it has a lower melting point and is suitable for brazing.

  Thus, the metal layer 15 of the sealing plate 3 is brazed to the bonding metal layer 8, so that the electrode 5 is connected to the terminal 10 via the current collector 18 b, the metal layer 15, the bonding metal layer 8, and the through electrode 21. Connect electrically.

At the opening side end of the side wall surrounding the concave portion 13 of the concave container 2, a metal layer 9 (metallized layer) is printed on the entire circumferential surface, for example, by tungsten conductor printing, and is formed when the ceramic is fired.
A joining metal layer 8 functioning as a seal ring is fixed to the metal layer 9 formed in the concave container 2 in advance using a brazing material such as gold brazing or silver brazing or a solder material.

The concave container 2 is made of, for example, ceramics using alumina. In the present embodiment, a plurality of flexible ceramic sheet materials 41 to 45 called green sheets are stacked and fired to be integrated. However, in FIG. 1A, the joint portions of the sheet materials 41 to 45 are indicated by broken lines. However, the concave container 2 may be formed not by laminating sheet materials but by baking alumina integrally formed with the concave portions 13.
The green sheet has openings corresponding to the recesses 13 and the reservoirs 17 and holes corresponding to the through holes in which the through electrodes 21 and 22 are installed. These green sheets are laminated in the thickness direction and fired. Thereby, the concave container 2 having the concave portion 13 and the through holes for the through electrodes 21 and 22 is formed. The diameter of the through electrode is formed to be about 100 μm.
The storage part 17 is formed in the center of the bottom part of the recessed part 13, and is provided in order to prevent the conductive paste from scattering or protruding before solidifying and causing a short circuit.
However, as the concave container 2, only the concave portion 13 may be formed without providing the storage portion 17.

The concave portion 13 has a rectangular cross section when viewed from above, and a concave storage portion 17 having a metal layer 11 formed on the bottom surface is formed at the bottom of the concave portion 13.
The metal layer 11 is formed by conducting conductor printing on the surface of the sheet material 42 corresponding to the bottom surface of the storage portion 17 and firing the concave container 2.
Here, the size of the metal layer 11 is reduced to the minimum necessary to reduce the cost. Note that the metal layer 11 may be formed on the entire bottom surface of the reservoir 17.
The conductor printing of the metal layer 11 is performed by screen printing with an ink containing a high melting point metal material that has corrosion resistance such as tungsten and can withstand firing of the concave container 2.

In order to protect the metal layer 11 made of tungsten from the electrolyte, aluminum (not shown) is vapor-deposited on the surface of the metal layer 11 and is further covered with a current collector 18a obtained by solidifying the conductive paste.
The method of coating the conductive paste film is by transfer, screen printing, ink jetting, coating with a dispenser, podding, or the like.
As the conductive paste, a paste obtained by processing a phenolic resin containing a carbon material (graphite powder, amorphous carbon (carbon black), etc.) for imparting conductivity and a solvent is used. The applied conductive paste is heated to dry the solvent and polymerize (solidify) the phenolic resin component, thereby forming a resin current collector 18a using a phenolic resin as a binder and carbon as a conductor. In addition, the electrode 6 is firmly fixed to the center of the storage portion 17 (the inner bottom surface of the concave container 2).

  The electrode 6 is formed by forming an electrode active material mainly composed of activated carbon into a sheet and cutting it into a rectangle. For example, a natural material is coconut husk, and an artificial material is a coal pitch, petroleum pitch or phenolic material. Resin carbides that are activated with water vapor, chemicals, or electrochemistry are used.

In the concave container 2, a through-hole penetrating the opening side end of the side wall and the bottom surface of the concave container 2 is formed in the side wall surrounding the concave portion 13, and a cylinder that electrically connects the bonding metal layer 8 and the terminal 10. A penetrating electrode 21 having a shape is disposed.
In addition, a through-hole penetrating the inner bottom surface of the concave portion 13 and the outer bottom surface of the concave container 2 is formed below the concave portion 13 of the concave container 2, and a cylindrical through hole that electrically connects the metal layer 11 and the terminal 12. An electrode 22 is provided.
The through electrodes 21 and 22 both seal the through hole of the concave container 2. The through electrodes 21 and 22 are also called VIA.

  The through electrodes 21 and 22 are filled with a metal paste mainly composed of a metal powder such as tungsten in the through holes and sintered, or a conductive paste such as carbon is injected and solidified, or a metal rod It is formed by inserting a material or a plate material. As the material of the through electrodes 21 and 22, for example, aluminum, stainless steel, tungsten, nickel, silver, gold, or conductive resin containing carbon can be used.

The terminals 10 and 12 functioning as external electrodes are formed by conducting conductor printing with an ink containing tungsten or the like and baking it, and then plating the surface with gold or nickel. Furthermore, a metal such as gold or tin can be plated on the nickel plating for rust prevention.
In addition, in this embodiment, although the terminals 10 and 12 were provided in the outer bottom face part of the concave container 2, you may form in an outer side face part, or may form continuously from an outer bottom face to a side face.
The terminals 10 and 12 are formed after the through electrodes 21 and 22 are installed in the through holes.

The electric double layer capacitor 1 configured as described above is surface-mounted on a substrate with the terminal 10 as a negative electrode and the terminal 12 as a positive electrode, and can be used as, for example, a mobile phone memory or a clock backup power source.
In this case, the mobile phone charges the electric double layer capacitor 1 at the same time that the battery of the main power source is mounted, and the electric charge accumulated in the electric double layer capacitor 1 is changed when the battery is replaced or when the voltage of the main power source decreases. Is discharged to supply power to the memory or to maintain a function such as a clock.

As described above, the overall configuration of the electronic component has been described by taking the electric double layer capacitor 1 as an example. Next, since the width and shape of the inclined portion 3b in the sealing plate 3 can be various forms, refer to the drawings. While explaining.
FIG. 2 shows a cross section of the inclined portion 3b of the sealing plate 3 in a direction orthogonal to the surface of the sealing flat surface portion 3a.
2A shows the arrangement relationship between the bonding metal layer 8 and the side wall portion of the concave container 2 connected to the sealing flat surface portion 3a of the sealing plate 3, but the other FIG. Since the sealing plate 3 shown in (d) is the same, the display is omitted.
In FIG. 2, the display of the metal layer 15 formed on the sealing plate 3 is omitted.

FIG. 2A shows the sealing flat surface portion 3a inclined at the same inclination angle as that of the electrode roll when seam welding described later is performed as in FIG.
However, when the sealing plate 3 is formed of stainless steel foil, it is inclined for positioning (an inclination angle smaller than the inclination angle of the electrode roll), and is further bent by the roll pressure of the electrode roll during welding, You may make it equal to the inclination-angle of an electrode roll.

FIG. 2B shows an example in which the inclined angle of the inclined portion 3b is bent at a right angle with respect to the sealing flat surface portion 3a.
When the contact surface with the electrode roll in seam welding is not considered, the shape of the inclined portion 3b shown in FIG. 2B is preferable.
Therefore, in the case of laser irradiation, the shape shown in FIG. 2B is preferable.

FIG. 2 (c) shows the inclined part 3b inclined in a right angle direction and formed with curved surfaces on both the inner side (concave container 2 side) and the outer side at the boundary part with the sealing flat part 3a.
On the other hand, FIG.2 (d) forms a curved surface only in the inner side (concave container 2 side) in the boundary part with the sealing plane part 3a.
Contrary to FIG. 2D, a curved surface may be formed only outside the boundary portion.

3 and 4 show modified examples of the shape of the sealing flat surface portion 3a in the sealing plate 3. FIG.
3 (a) to (d) and FIGS. 4 (a) to (d) of this modification correspond to the shapes of the inclined portions 3b described in FIGS. 2 (a) to (d), respectively. Yes.
In this modification, the sealing flat surface portion 3a of the sealing plate 3 is formed with a concave portion on the concave container 2 side or the opposite side.

In the modification of FIG. 3, a concave portion 310 is formed on the concave container 2 side of the sealing flat surface portion 3a, and the opposite side is formed in a convex state. The recess 310 is formed on the inner side (center side) of the inner peripheral surface of the bonding metal layer 8 in order to secure a bonding surface with the annular bonding metal layer 8.
On the other hand, in the modification of FIG. 4, the recessed part 320 is formed in the opposite side to the concave container 2 side of the sealing plane part 3a, and the concave container 2 side is formed in the convex state. The recess 320 is formed on the inner side (center side) of the inner peripheral surface of the bonding metal layer 8 in order to secure a bonding surface with the annular bonding metal layer 8. In the modification of FIG. 4, an inclined portion for forming the recess 320 is also formed inside the annular bonding metal layer 8, and positioning is performed on both the inside and outside of the bonding metal layer 8 together with the inclined portion 3b. Will be.

In the modification shown in FIGS. 3 and 4, the inner bottom surfaces of the recesses 310 and 320 (both of which are on the concave container side) are formed to have an area larger than that of the electrode 5.
When the sealing plate 3 is formed of stainless steel foil, the planar strength can be increased by forming the recesses 310 and 320.

FIG. 5 shows the planar shape (the shape seen from above) of the inclined portion 3 b in the sealing plate 3. In addition, you may make it employ | adopt the modification shown in FIG. 3, 4 about the sealing plane part 3a.
FIG. 5A shows an inclined portion 3b formed over the entire outer periphery of the sealing flat surface portion 3a. As will be described later, when performing parallel seam welding using a frustoconical electrode roll, the shape is most suitable for enabling reliable welding with a low current over the entire circumference.
FIG. 5B shows a pair of inclined portions 3b facing each other at the center of the long side and the short side of the sealing flat surface portion 3a. Thus, in order to position, it is preferable to provide a pair of inclined portions 3b opposed to both sides, but one inclined portion 3b may be formed on each adjacent side.
In addition, the pair of inclined portions 3b provided on both sides of the long side and the short side are illustrated as being opposed to each other. However, the inclined portions 3b are formed so as to be partially opposed or not opposed at all. May be.

FIG.5 (c) provides the inclination part 3b in the four corners (corner part) of the sealing plane part 3a.
Since each inclined portion 3b includes a portion extending from the long side and a portion extending from the short side, the single inclined portion 3b can be positioned in either the long side direction or the short side direction. For this reason, in the example of FIG. 5C, the inclined portions 3b are provided at the four corners, but one inclined portion 3b is provided at any one corner, and the inclined portions 3b are provided at two or three locations. It may be. When providing in two places, you may make it provide in two adjacent corners or both corners on a diagonal.

FIG. 5 (d) is an example in which an inclined portion 3b is provided on the entire long side of the sealing flat surface portion 3a, and an inclined portion 3b having both end sides shortened by a predetermined length is provided on the short side.
The length on the short side is arbitrary, but when the entire circumference is welded by parallel seam welding described later, the length reaches the welding region on the long side. That is, it is preferable that the inclined part 3b on the short side has a length that reaches the long side wall that surrounds the concave part 13 of the concave container 2 and a length that reaches the center of the side wall. This is for performing parallel seam welding by energizing through the inclined portion 3b over the entire circumference.
Note that the long side and the short side in FIG. 5D may be reversed, and the inclined portion 3b having the same length as the short side and the inclined portion 3b shorter than the long side by a predetermined length may be used.

FIG. 5E shows the planar shape of the sealing plate 3 when the planar shape of the electronic component (the shape of the concave container 2) is circular.
As shown in FIG. 5 (e), the inclined portions 3b are provided at three places, but two places are also possible. When providing the inclined part 3b in two places, it is preferable that the angle between both virtual lines which connect each inclined part 3b and a center shall be about 45 to 60 degree | times.
Similarly to FIG. 5A, the inclined portion 3b can be formed over the entire circumference of the sealing flat surface portion 3a.

Next, a method for sealing the concave container 2 with the sealing plate 3 through the bonding metal layer 8 will be described.
In addition, although brazing by heating with a laser is also possible as described above, parallel seam welding will be described here.
FIG. 6 shows a state in which the sealing plate 3 is brazed to the concave container 2 by the joining metal layer 8 by parallel seam welding.
As shown in FIG. 6, the pair of electrode rolls 52 and 54 used in parallel welding have a truncated cone shape and are rotatably supported by the anode arm 51 and the cathode arm 53, respectively.
The electrode roll 52 is connected to the anode of the power source 60 through the anode arm 51, and the electrode roll 54 is connected to the cathode of the power source 60 through the cathode arm 53.
Although not shown, the power source 60 is connected via an energization control unit that controls energization between the electrode roll 52 and the electrode roll 54.

In parallel seam welding, the sealing plate 3 is sandwiched between the electrode rolls 52 and 54 from both sides thereof, and the electrode roll is rotated at a predetermined interval (indicated by a white arrow in FIG. This is done by energizing in time or distance.
Then, the bonding metal layer 8 is heated by the contact resistance during energization, pressurization and heating are performed, the bonding metal layer 8 is melted and fused with the metal layer 15 by heating, and the recess 13 is sealed with the sealing plate 3. The

FIG. 7 shows a contact state between the electrode roll 54 and the sealing plate 3.
FIG. 7A shows a contact state when the inclined portion 3 b is formed on the sealing plate 3. That is, it is a contact state when the inclined portion 3b is formed over the entire circumference of the sealing flat surface portion 3a, or a contact state in the inclined portion 3b when the inclined portion 3b is partially formed.
On the other hand, FIG.7 (b) represents the contact state in case the inclination part 3b is not formed. That is, in a state of contact with the conventional sealing plate 103 (see FIG. 9) where the inclined portion 3b does not exist, or when the inclined portion 3b is formed in a part of the sealing flat surface portion 3a. Contact state.

  As shown in FIG. 7A, the sealing plate 3 is in contact with the electrode rolls 52 and 54 with a sufficient area due to the presence of the inclined portion 3b, so that the energization current is reduced as compared with the state of FIG. 7B. be able to.

FIG. 8 shows a welding procedure and a welding state with respect to the joining metal layer 8, and the same applies to both laser welding and parallel seam welding. However, in parallel seam welding, the welding location is outside of FIG.
In the case of the parallel seam welding described in FIG. 6, after welding one of the long side in FIG. 8A and the short side in FIG. 8B, the other is welded.
As shown in the figure, the welding is performed in a plurality of times. In the figure, the dotted circle is the first welding and the practical circle is the second welding.
By energizing by parallel seam welding or irradiating with laser, it is welded in a range of a predetermined area (a range indicated by a dotted line or a practical circle). When the length in the welding direction of this predetermined area to be welded is L (about 100 μm), the first welding is performed at a pitch interval of approximately L + α, and the second welding is shifted by 1/2 pitch. Done.
Here, α is, for example, in the range of about 0 to 50 μm.

  Thus, overheating is prevented by preventing the same part from being welded continuously for the purpose of being indicated by a dotted circle or a practical circle.

DESCRIPTION OF SYMBOLS 1 Electric double layer capacitor 2 Concave container 3 Sealing plate 3a Sealing plane part 3b Inclination part 310 Concave part 320 Concave part 5 Electrode 6 Electrode 7 Separator 8 Bonding metal layer 9 Metal layer 10 Terminal 11 Metal layer 12 Terminal 13 Concave part 15 Metal layer 17 Storage part 18a, 18b Current collector 19a, 19b Meniscus 21, 22 Through electrode 41-45 Sheet material

Claims (8)

A concave container;
A sealing plate for sealing the concave container;
A first internal electrode disposed in the concave container;
A first external electrode formed outside the concave container;
First connection means for electrically connecting the first internal electrode and the first external electrode;
A second internal electrode disposed in the concave container at a predetermined interval from the first internal electrode;
A second external electrode formed outside the concave container;
Second connection means for electrically connecting the second internal electrode and the second external electrode;
With
The sealing plate is formed larger than at least a welded portion located inside the concave container, and includes an inclined portion inclined toward the concave container side.
An electronic component characterized by that. The concave container and the sealing plate are joined by seam welding via an annular joining metal layer,
The electronic component according to claim 1. The inclined portion is formed over the entire circumference.
The electronic component according to claim 1, wherein the electronic component is an electronic component. The seam welding is performed by energizing the sealing plate with a pair of frustoconical electrode rolls,
The inclined portion of the sealing plate is formed at the same angle as the inclination angle of the electrode roll surface,
The electronic component according to claim 3. The inclined portion of the sealing plate is formed by a pressing force by the pair of electrode rolls during welding by the pair of electrode rolls.
The electronic component according to claim 4. In the sealing plate, a concave portion in the concave container side direction or the opposite side direction is formed on a surface facing the concave portion formed in the concave container.
The electronic component according to claim 1, wherein the electronic component is any one of claims 1 to 5. The sealing plate is made of stainless steel,
The electronic component according to any one of claims 1 to 6, characterized in that: An electronic component according to any one of claims 1 to 7, and
Power storage means for storing power in the electronic component;
With other electronic components that perform the specified function,
Power supply means for supplying power to the other electronic component using the stored charge;
An electronic device comprising:

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