JP5828503B2 - Electronic component and electronic device - Google Patents

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.

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. 10 is a cross-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 having a vertical inner wall is formed, and the positive electrode 106 is bonded 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 metal sealing plate 103 is joined to the opening of the recess 113 by the metal joining metal layer 108 to seal the recess 113. Note that a metal layer 115 is formed on the lower surface of the sealing plate 103, and the metal layer 115 is bonded to the bonding metal layer 108.
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 bonded to the lower surface of the sealing plate 103, and is electrically connected to the negative electrode terminal 110 through the sealing plate 103, 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 an electrolyte is sealed in the recess 113.
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.

However, when the positive electrode 106, the separator 107, and the negative electrode 105 are disposed in the recess 113, there is a possibility that the negative electrode 105 and the positive electrode 106 are short-circuited if a deviation occurs.
When the separator 107 is made of a thermoplastic material, the separator 107 may contract due to heating when the recess 113 is sealed with the sealing plate 103, and the negative electrode 105 and the positive electrode 106 may be short-circuited.

JP 2001-216852 A

  An object of the present invention is to improve the yield of an electric double layer capacitor or the like.

(1) In the invention described in claim 1, the container is formed by laminating sheet materials, the step is formed on the inner wall, and the hollow portion is formed in a rectangular parallelepiped shape, and is in contact with the step surface of the step. Installed in a rectangular shape separating the cavity into two regions, a first electrode installed in a region on one side of the separator, and a region on the other side of the separator A second electrode connected to the first electrode and connected to the outside of the container, and a second conductor connected to the second electrode and connected to the outside of the container And an electrolyte in contact with the first electrode and the second electrode. The separator has four corners in the cavity and the first electrode side and the second electrode. An electronic part characterized in that a communication part communicating with the electrode side is formed To provide.
(2) The invention according to claim 2 provides the electronic component according to claim 1 , wherein the communication portion has a notch shape.
(3) In the invention described in claim 3, at least a portion of the end portion of the separator, according to claim 1 or claim, characterized in that it is fixed by being sandwiched between the said stepped surface first electrode Item 2. An electronic component according to Item 2 is provided.
(4) In the invention according to claim 4, the end of the separator is fixed by being sandwiched between the step surface and the first electrode over the entire circumference. to provide an electronic component according to any one of claims of claims 3.
(5) In the invention according to claim 5, the length of the step surface in the movable direction is longer than the maximum value of the movable distance on the step surface of the separator placed on the step surface. The electronic component according to any one of claims 1 to 4 , wherein the electronic component is set large.
(6) In the invention described in claim 6, the electronic component according to any one of claims 1 to 5 , power storage means for storing electricity in the electronic component, and a predetermined function are exhibited. There is provided an electronic apparatus comprising: another electronic component that performs power supply, and a power supply unit that supplies power to the other electronic component using the stored charge.

  According to the present invention, the yield of an electric double layer capacitor or the like can be improved by forming a step in the recess and installing a separator on the step.

It is a figure for demonstrating 1st Embodiment and the modification 1 of 1st Embodiment. It is a figure for demonstrating the modification 2 of 1st Embodiment. It is a figure for demonstrating the magnitude | size of a separator. It is a figure for demonstrating the formation pattern of a step part. It is a figure for demonstrating the formation pattern of a step part. It is a figure for demonstrating 2nd Embodiment and the modification 1 of 2nd Embodiment. It is a figure for demonstrating the modification 2 of 2nd Embodiment. It is a figure for demonstrating the modification 3 of 1st Embodiment and 2nd Embodiment. It is a figure for demonstrating the modification 4 of 1st Embodiment and 2nd Embodiment. It is a figure for demonstrating a prior art example.

(1) Outline of Embodiment The concave portion 13 (FIG. 1A) has a two-stage structure having a step portion 51. The upper and lower electrodes 5 and 6 are separated by the separator 7 placed on the stepped portion 51.
The size of the separator 7 is set such that the opening by the step portion 51 is covered by the separator 7 even if the separator 7 is displaced to the maximum.
Therefore, even if the separator 7 is displaced, it is possible to effectively suppress a problem that the electrode 5 and the electrode 6 are short-circuited.
Moreover, the concave container 2 is formed by laminating and firing the sheet materials 41 to 44. By forming openings corresponding to the shape of the recesses 13 in the sheet materials 43 and 44, the recesses 13 and the step portions 51 can be easily formed.

(2) Details of the embodiment (first embodiment)
An electrochemical cell constituting the electronic component of the present embodiment will be described with reference to the drawings. In the following, an electric double layer capacitor will be described as an example as an embodiment, but the electronic component may be another type of electrochemical cell such as a nonaqueous electrolyte battery.

  FIG. 1A is a side sectional view of the electric double layer capacitor 1 according to the first embodiment. The electric double layer capacitor 1 has a rectangular parallelepiped shape, and the size is, for example, a rectangular parallelepiped having a height of 1 [mm] or less, a length of about 2.5 [mm], and a width of about 3.0 [mm]. It has a shape.

Electric double layer capacitor 1, concave container 2 having a recess 13 with a step 51 formed in the middle, sealing plate 3 with a metal layer 15 formed on the lower surface, electrode 5 used as a negative electrode, used as a positive electrode The electrode 6, the separator 7, the bonding metal layer 8, the metal layer 9, the metal layer 11, the terminal 10, the terminal 12, and an electrolyte (not shown) sealed in the recess 13 are 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. 1, 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.

The concave container 2 is made of ceramics containing, for example, 90 wt% or more of an alumina component, and is formed by stacking and integrating a plurality of flexible ceramic sheet materials 41 to 44 called green sheets. It is formed. The thickness of each sheet after baking can be set to 100 to 300 μm, and the thickness of the side wall can be set to 100 to 500 μm. In Fig.1 (a), the junction part of the sheet | seat materials 41-44 is shown with the broken line.
An opening is formed in the sheet material 43 and the sheet material 44, and the opening of the sheet material 43 is formed smaller than the opening of the sheet material 44 by the size of the stepped portion 51.
For this reason, if the sheet | seat materials 41-44 are laminated | stacked and baked, the concave container 2 which has the recessed part 13 in which the step part 51 was formed will be formed.
Thus, since the concave container 2 is formed by laminating the sheet materials, the step shape can be easily formed.

The metal layer 11 is formed by conducting conductor printing in advance on the surface of the sheet material 42 with a paste containing a metal powder such as tungsten (W) and firing the concave container 2. A portion of the metal layer 11 that is in contact with the electrode 6 functions as a current collector.
Furthermore, the metal layer 11 penetrates the concave container 2 along the surface of the sheet material 42, and is connected to the terminal 12 through the side surface of the concave container 2. The portion formed on the outer side surface of the concave container 2 is formed after the concave container 2 is laminated. The metal layer 11 electrically connects the electrode 6 and the terminal 12.
Similarly, the metal layer 9 is also formed on the side surface of the concave container 2 to electrically connect the bonding metal layer 8 and the terminal 10, and the electrode 5 and the terminal 10 include the metal layer 15, the bonding metal layer 8, and the metal layer 9. Is electrically connected.
On the side surface of the concave container 2 where the metal layer 9 is formed, auxiliary electrodes are provided on the upper surfaces of the sheet materials 41 to 46 so that the electrical connection at the side surface is more reliable.

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.
Tungsten is suitable as an electrode to be formed in the recess 13 because it has a high melting point, hardly oxidizes, has an appropriate adhesion strength with the ceramic surface, and has a practical electrical resistance after firing. However, when tungsten is used as the positive electrode current collector, when a voltage is applied in contact with the electrolyte, it dissolves electrochemically into the electrolyte. Therefore, at least a portion of the surface of the metal layer 11 that is in contact with the electrolyte is used. A protective film (conductive protective layer) is required.
When a conductive protective layer is formed on the metal layer 11 using tungsten, a metal having good corrosion resistance such as aluminum, titanium, or niobium is formed by a thick film method such as a vacuum evaporation method or an RF sputtering method. In addition, a conductive resin can be used as the conductive protective layer.
Note that the conductive protective layer may be formed by using wet plating with Au or Cu. Further, it may be formed by Cu alloy plating or Au alloy plating.
In the present embodiment and the modification, although illustration of the conductive protective layer (protective film) for the metal layers 9 and 11 is omitted, the conductive layers are formed as described above.

The electrode 6 is joined to the upper surface of the metal layer 11 with a conductive adhesive containing carbon.
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.

A joining metal layer 8, which is a metal layer for joining the sealing plate 3 and the concave container 2, is formed at the end of the opening of the recess 13.
The joining metal layer 8 is composed of a metallized layer formed on the entire periphery of the end of the opening and a layer of brazing material (silver brazing, gold brazing, silver-copper brazing, etc.) formed on the metallizing layer. ing. The bonding metal layer 8 is sometimes called a seal ring in order to ensure airtightness between the sealing plate 3 and the concave container 2.

The bonding metal layer 8 is made of, for example, Kovar (alloy having a ratio of Co: 17, Ni: 29, Fe: 54), and the surface of the Kovar is made of a single metal or a plurality of kinds of metals such as nickel, gold and tin. It is repeatedly plated and is fixed by installing a metal ring made of Kovar at the end of the concave container 2 and welding the brazing material such as the above-mentioned silver brazing.
As will be described later, when the sealing plate 3 is placed in the opening of the recess 13 and heated, nickel on the surface of the metal ring melts as a brazing material and fuses with the metal layer 15 of the sealing plate 3, and the recess 13 becomes the sealing plate. 3 is sealed.

  A metal layer 9 connected to the bonding metal layer 8 and the terminal 10 is formed from the side surface to the upper surface of the concave container 2, whereby the bonding metal layer 8 and the terminal 10 are electrically connected. The metal layer 9 is made of the same material as that of the metal layer 11, and the bonding metal layer 8 is formed after the sheet materials 41 to 44 are laminated.

The terminals 10 and 12 are formed by conducting conductor printing with an ink containing tungsten or the like and baking it, and then plating gold, nickel, tin or the like on the surface thereof. The plating includes electrolytic plating and electroless plating, and may be formed by a vapor phase method such as vacuum deposition.
Thereby, the high solder wettability of the terminals 10 and 12 is ensured, and the electric double layer capacitor 1 can be satisfactorily surface-mounted on the substrate.
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 sealing plate 3 is a metal member made of Kovar or the like. Since Kovar has a thermal expansion coefficient approximately equal to that of ceramics, it is possible to suppress the stress generated between the sealing plate 3 and the concave container 2 when the electric double layer capacitor 1 is heated during reflow.
On the lower surface of the sealing plate 3, a metal layer 15 is formed by nickel plating in order to bond the sealing plate 3 to the bonding metal layer 8 satisfactorily.
When the metal layer 15 is brazed to the bonding metal layer 8, the sealing plate 3 is physically and electrically bonded to the opening of the recess 13.

In brazing, the sealing plate 3 is melted by being heated while being pressurized, 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 roller electrode is brought into contact with the edge of the sealing plate 3 with an appropriate pressure and is rotated while being energized. The bonding metal layer 8 is heated by the contact resistance, and pressurization and heating are performed. In addition to parallel seam welding, heat welding with a pulsed laser is also possible while pressurizing the sealing plate 3 with glass or the like that can transmit laser.

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. Thereby, it is not necessary to raise the welding power more than necessary.
Further, as a brazing material for joining the metal layer 9 and the joining metal layer 8, a brazing material such as gold brazing, silver brazing, or silver-copper brazing, or a solder material can be used.

An electrode 5 made of an electrode active material is joined to the lower surface of the metal layer 15 by a conductive adhesive containing carbon.
The material, shape and size of the electrode 5 are the same as those of the electrode 6. The portion of the metal layer 15 that is in contact with the electrode 5 functions as a current collector. And the part which is not in contact with the electrode 5 of the metal layer 15 functions as a conductor bonded to the current collector.
In this way, the electrode 5 is electrically connected to the terminal 10 via the metal layer 15, the bonding metal layer 8, and the metal layer 9.

The electrodes 5 and 6 face each other in a cavity formed by the recess 13 and the sealing plate 3, and a separator 7 is installed between the electrodes 5 and 6 to prevent a short circuit due to contact of the electrodes 5 and 6. Has been.
Examples of the material of the separator 7 include non-woven fabric made of a material imparting hydrophilicity to the surface, such as heat-resistant resin such as PPS (polyphenylene sulfide), PEEK (polyether ether ketone), and modified PEEK, and PTFE (polytetrafluoro). Ethylene), porous films made of the above-mentioned resins, or glass fibers can be used. Cellulosic separators may also be used.
The separator 7 preferably has not only a function of preventing a short circuit between the electrode 5 and the electrode 6 but also a function of containing more electrolyte, that is, a function of retaining a high electrolyte. As the separator 7 of the present embodiment, PTFE is used, and glass fiber is most desirable from the viewpoint of the liquid retention function.

The height of the step portion 51 is formed above the vicinity of the upper surface of the electrode 6. And the magnitude | size of the separator 7 is set larger than the opening part by the step part 51, and the edge part of the separator 7 is installed on the step part 51. FIG.
Further, as will be described later, the size of the separator 7 is set to a size that does not fall off the step portion 51 even if the separator 7 slides on the step portion 51.
When the size of the separator 7 is set in this way, even if the separator 7 moves to the maximum extent, the opening by the stepped portion 51 is always covered by the separator 7 and the electrodes 5 and 6 are not short-circuited.
When the wall surface is tapered as shown in FIG. 1B, it is difficult to break even by a load when welding the joining metal layer 8 and the sealing plate 3, and the electrodes can be easily inserted. The taper angle is preferably 1 to 5 degrees. Although not shown, other wall surfaces are also tapered.

Further, an electrolyte is enclosed in a hollow portion constituted by the recess 13 and the sealing plate 3.
The electrolyte is composed of a solution in which a supporting salt such as (CH3). (CH4) 3N.BF4 is dissolved in a nonaqueous solvent such as PC (propylene carbonate) or SL (sulfolane). As described above, in the present embodiment, a liquid is used as the supporting salt. However, it is also possible to use a gel or solid electrolyte in combination or as a single substance. Although depending on the sealing method, when a liquid solvent is used as the electrolyte, the boiling point is desirably 200 ° C. or higher.

  Furthermore, it is desirable that the vapor pressure does not increase due to the heat applied during sealing. A low boiling point solvent having a boiling point of less than 100 ° C. can be added to the electrolytic solution, but at least the vapor pressure at the melting point of the resin is preferably 0.2 MPa-G or less. When injecting an electrolytic solution, the electrolyte can be impregnated into the details of the electrode by injecting the electrolytic solution into the concave portion 13 and then singly or in combination with reduced pressure, heating, or increased pressure.

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.
Further, by using an electrode having a positive electrode active material such as Li4Ti5O12, Li4Mn5O12, LiCoO2, a negative electrode containing Li-Si-O, Li-AL, or the like, and an electrolytic solution in which 1M LiBF4 is dissolved in PC, lithium is used. An ion battery can be constructed. At this time, a conductive additive or a binder can be used in combination with each active material.
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.

In the above, the concave container 2 is made of ceramics (HTCC) whose main component is alumina, but it can also be made of heat-resistant materials such as heat-resistant resin, glass, ceramic glass, and low-temperature co-fired ceramics (LTCC). It is.
When the concave container 2 is formed of glass or glass ceramic, a low melting point metal material mainly composed of silver is provided on a low melting point glass or glass ceramic by conductor printing, laminated, and then fired at a low temperature.

(Modification 1)
FIG.1 (c) is the figure for demonstrating the modification 1 which concerns on 1st Embodiment.
In the first embodiment described above, the mutually facing surfaces of the electrodes 5 and 6 are set to the same size, but in the first modification, the electrode 5 is set to be large.
The surface (lower surface) of the electrode 5 facing the electrode 6 is set larger than the opening formed by the step portion 51.
The distance between the lower surface of the electrode 5 and the step portion 51 is set to be smaller than the thickness of the separator 7.

For this reason, when the concave portion 13 is sealed with the sealing plate 3, the end portion 61 of the separator 7 is sandwiched and fixed between the step portion 51 and the lower surface of the electrode 5.
As described above, since the end portion 61 of the separator 7 is sandwiched and fixed between the upper surface of the step portion 51 and the lower surface of the electrode 5, it is possible to prevent the separator 7 from being displaced.
Furthermore, even when the separator 7 is contracted by heating, the contraction can be suppressed by fixing the end portion 61.

(Modification 2)
FIG. 2 is a diagram for explaining a second modification according to the first embodiment.
In this example, the lower surface of the electrode 5 is formed smaller than the upper surface of the electrode 6.
In this case, since the positive electrode (electrode 6) is larger than the negative electrode (electrode 5), it is advantageous for power storage as follows.

The electric double layer capacitor applies, for example, a voltage exceeding 0 V to the electrode 5 and a voltage exceeding 2.6 V to the electrode 6. At this time, since a voltage is applied to the negative side of the electrode 5, cations are adsorbed, and since a voltage is applied to the electrode 6 on the positive side, anions are adsorbed.
By continuing to apply this voltage, the cation and anion constituting the solvent and the supporting salt of the electrolytic solution are decomposed in the electrolytic solution. By storing the voltage applied to each electrode in the potential window, decomposition of the constituent components of the electrolytic solution can be suppressed and avoided.
As a method of storing in the potential window, there is a method of shifting the potential while maintaining the voltage applied to both electrodes, and the potential can be shifted by reducing the density of ions adsorbed on the electrode.

Reducing the density of ions adsorbed on the electrode can be realized by changing the specific surface area of one electrode compared to the other. That is, as in Modification 2 described above, when an electrode having a specific surface area per unit volume is used, this can be realized by forming the lower surface of the electrode 5 smaller than the upper surface of the electrode 6.
By shifting this potential, the voltage applied to both electrodes can be stored in the potential window, the deterioration of the electrolyte can be suppressed, and a capacitor with stable quality can be obtained.

FIG. 3 is a diagram for explaining the size of the separator 7.
Here, it is assumed that the separator 7 is installed on the step portions 51a and 51b, and the moving direction of the separator 7 is the direction in which the step portions 51a and 51b are formed. As shown in the figure, the separator 7 is set to be larger than the opening formed by the step portions 51a and 51b.
The distances between the separator 7 and the wall surface of the recess 13 are L1 and L2, and the lengths of the step portions 51a and 51b (distance protruding from the wall surface of the recess 13) are M1 and M2.
In this case, even if the separator 7 slides on the step portions 51a and 51b, the length that the separator 7 always covers the opening by the step portions 51a and 51b, or the length that does not fall off from the step portions 51a and 51b. Is L1 + L2> (the smaller of M1 and M2) (1).
In the example of FIG. 3, since M1 <M2, Expression (1) is L1 + L2> M1.
In consideration of the case where the separator contracts, the separator 7 is made larger than the theoretically required minimum value to provide a margin.

Each figure of FIG. 4 is a figure for demonstrating the formation pattern of the step part 51. FIG.
As shown in the figure, when viewed from above, the concave container 2 and the concave portion 13 have a rectangular shape.
Although it can be formed in a circular shape, a dead space is generated when it is installed on a substrate. Therefore, the electric double layer capacitor 1 has a rectangular shape.
When viewed from above, the bonding metal layer 8 (seal ring) has a square shape with R. Thickness is about 0.15mm. The metal layer 9 is gold-plated for rust prevention on the upper surface of nickel plating.

FIG. 4A shows an example in which a step portion 51 is formed on the entire circumference of the recess 13. By forming the step portion 51 on the entire circumference, the opening by the step portion 51 is covered with the separator 7 regardless of the direction in which the separator 7 moves, and the short circuit between the electrode 5 and the electrode 6 can be effectively prevented. it can.
FIG. 4B is an example in which a step 51 is set on the longer side of the rectangular shape, and FIG. 4C is an example in which the step 51 is set on the shorter side of the rectangular shape.
In this way, when the step portions 51 are formed in one pair of the two pairs of rectangular shapes, the installation area of the electrode 6 can be increased, and the electrode 6 can be enlarged.
FIG. 5D is an example in which stepped portions 51 are formed at the four corners of the recess 13, and FIG. 5E is an example in which the stepped portions 51 are formed on the four sides of the recessed portion 13 except for the four corners.

(Second Embodiment)
FIG. 6A is a side sectional view of the electric double layer capacitor 1 according to the second embodiment.
In the present embodiment, the electrode 5 and the terminal 10, and the electrode 6 and the terminal 12 are connected by the through electrodes 21 and 22 that penetrate the inside of the main body of the concave container 2.
Hereinafter, the through electrodes 21 and 22 will be described. The through electrode is made of tungsten (W) and is also called VIA.

Under the concave portion 13 of the concave container 2, sheet materials 41 and 42 having holes for the through electrodes 22 are laminated, so that the diameter of the opening having openings on the bottom surface of the concave portion 13 and the bottom surface of the concave container 2 is about 0. A 1 mm through hole is formed.
A cylindrical through electrode 22 that electrically connects the metal layer 11 and the terminal 12 is formed in the through hole.
The outer diameter of the through electrode 22 and the inner diameter of the through hole are set to be the same, and an intermediate electrode larger than the cross-sectional area of the through hole is formed so that no gap is generated between the through electrode 22 and the inner wall of the through hole. doing.

  The through electrode 22 can be formed simultaneously with the firing of the container by pouring a paste containing metal tungsten particles into the through hole in advance. Further, it is formed by injecting and solidifying a conductive paste or inserting a metal bar. As the metal material, for example, aluminum, stainless steel, tungsten, nickel, silver, gold, or a conductive resin containing carbon can be used. The electrode 6 is electrically connected to the terminal 12 via the metal layer 11 and the through electrode 22 via the protective layer.

Further, each of the sheet materials 41 to 44 has a hole for the through electrode 21 having a diameter of about 0.1 mm. By laminating the sheet materials 41 to 44, the recesses 13 are formed in the side walls surrounding the recess 13. A through-hole having an opening is formed at the end of the opening and the bottom surface of the concave container 2.
A cylindrical through electrode 21 that electrically connects the bonding metal layer 8 and the terminal 10 is formed in the through hole, whereby the bonding metal layer 8 and the terminal 10 are electrically connected. . For this reason, the electrode 5 is electrically connected to the terminal 10 through the metal layer 15, the bonding metal layer 8, and the through electrode 21.
The outer diameter of the through electrode 21 and the inner diameter of the through hole are set to be the same, and no gap is generated between the through electrode 21 and the inner wall of the through hole.
The material and forming method of the through electrode 21 are the same as those of the through electrode 22.

When the wiring is formed on the side surface of the concave container 2 like the metal layers 9 and 11 of the first embodiment, when the electric double layer capacitor 1 is surface-mounted on the substrate, the solder is the metal layer 9, In this embodiment, wirings connecting the electrode 5 and the terminal 10 and the electrode 6 and the terminal 12 are formed inside the main body of the concave container 2. Therefore, it is possible to prevent the solder from creeping up.
In addition, since both ends of the through hole of the through electrode 22 are sealed by the metal layer 11 and the terminal 12, even when the vapor pressure of the electrolyte in the recess 13 is increased by heating during reflow, leakage of the electrolyte can be prevented. it can.

The end portions of the terminals 10 and 12 are not formed to the end portion of the bottom surface of the concave container 2, and the end portions of the terminals 10 and 12 and the bottom end portion of the concave container 2 are not aligned.
With this configuration, when a large number of electric double layer capacitors 1 are formed on a large sheet material at one time and divided to take out individual electric double layer capacitors 1 (sometimes called chocolate breaks), the division is performed. Accordingly, it is possible to prevent the terminals 10 and 12 from being peeled off or cracked. This is an example, and the terminals 10 and 11 may be formed up to the end of the bottom surface of the concave container 2.
Alternatively, the terminals 10 and 11 may be formed continuously from the bottom surface to the side surface. In this case, the end portions of the terminals 10 and 12 are on the side surface of the concave container 2 and are perpendicular to the substrate.
For this reason, when the electric double layer capacitor 1 is reflowed, the solder crawls up and solidifies the vertical portions of the terminals 10 and 12 to improve the bonding strength between the electric double layer capacitor 1 and the substrate.

(Modification 1)
FIG. 6B is a side cross-sectional view of the electric double layer capacitor 1 according to the first modification of the second embodiment.
In the present modification, the through electrode 22 is set such that the diameter at the sheet material 42 is larger than the diameter at the sheet material 41, and even when the pressure in the concave portion 13 is increased by heating during reflow, It is possible to prevent the pressure from acting on the through electrode 22 and the through electrode 22 from falling out of the concave container 2.
Similarly, the through electrode 21 is set such that the diameter of the sheet material 44 is larger than the diameter of the sheet materials 41 to 43.

(Modification 2)
FIG. 7 is a side cross-sectional view of an electric double layer capacitor 1 according to Modification 2 of the second embodiment.
The concave container 2 is formed by laminating sheet materials 41 to 45.
In this modification, the opening of the sheet material 44 is set larger than the opening of the sheet material 43, and the opening of the sheet material 45 is set larger than the opening of the sheet material 44.
As a result, a step 51 is formed by the sheet material 43, and a step 52 is formed by the sheet material 44.
As described above, in the present modification, the two step portions 51 and 52 are provided in the concave portion 13. However, since the concave container 2 is formed by stacking the sheet materials, such a complicated step portion can be easily formed. Can be formed.

In the step portion 51, the separator 7 is installed as in the first embodiment.
On the upper surface of the stepped portion 52, the metal layer 16 is formed on the side of the stepped portion 52 on the through electrode 21 side. The metal layer 16 is formed by the same material and manufacturing method as the metal layer 11.
Then, one end of the electrode 5 is joined on the metal layer 16.
Note that a gap is provided between the other end of the electrode 5 and the stepped portion 52, and an electrolyte is injected between the electrode 5 and the electrode 6 through the gap.

The metal layer 16 penetrates into the main body of the concave container 2 along the surface of the sheet material 44, and is joined to the through electrode 21 inside the main body of the concave container 2.
For this reason, the electrode 5 is electrically connected to the terminal 10 via the metal layer 16 and the through electrode 21.
In the modified example 2, since the sealing plate 3 is not used as a current collector, the sealing plate 3 can be formed of an insulating member such as a resin sheet material.

For this reason, the sheet materials 41 to 45 may be formed by laminating resin sheet materials and sealed with a sealing plate 3 that is also a resin sheet material.
As the resin, for example, PTFE (polytetrafluoroethylene) or PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer) can be used.

  In addition, an aluminum foil is installed on the upper surface of the electrode 5, and an end of the aluminum foil is joined to the metal layer 16, thereby providing an aluminum foil current collector on the upper surface of the electrode 5. The power storage / discharge function of the multilayer capacitor 1 can also be enhanced.

Next, a modified example related to the separator 7 will be described.
In addition, about the modified example of the separator 7 demonstrated below, although the case where it arrange | positions on the step part 51 is demonstrated to an example, with respect to the electrical double layer capacitor (for example, refer FIG. 10) in which the step part 51 is not formed. It is possible to apply.

FIG. 8 is a view for explaining another modification 3 with respect to the first embodiment and its modifications 1 and 2 and the second embodiment and its modification 1, with respect to the separator 7 and the electrode 5. It is a representation.
FIG. 8A shows the separator 7 and the electrode 5 having a basic shape applied to each of the embodiments and modifications described in FIG. As shown in FIG. 8A, the basic separator 7 has a flat plate shape. In FIG. 1A, the electrode 5 is displayed in a state of being separated from the separator 7. However, as shown in FIG. 8A, the electrode 5 is in contact with the separator, or the electrode 5 is The separator may be in a pressurized state.

On the other hand, in the separator 7 of the modified example 3, as shown in FIGS. 8B and 8C, the separator 7 is formed of a flat plate portion 7a and a wall portion 7b formed on the outer edge thereof. The flat plate portion 7a of the separator 7 is in contact with the electrode 7 (may be separated as shown in FIG. 1A), while the wall portion 7b is opposed to the outer peripheral side surface of the electrode 5.
In addition, about the wall part 7b, it may be formed over the outer periphery whole surface of the plane part 7a, and may be formed about a part. In the case of being formed as a part, in addition to the case where it is formed on the entire two opposite sides of the flat surface portion 7a, it is formed on all sides, but not on the entire length of the side, There is a case where it is formed on the entire side, or a case where it is formed on a part of any side.
According to the third modification, the contact between the electrode 5 and the electrode 6 can be avoided more reliably.

FIG. 8B shows the third modification in which the outer edge portion of the separator 7 is curved. As a material of the separator 7 when the outer edge portion is curved as shown in FIG. 8B, a material that maintains the curved shape is preferable, and for example, PTFE is suitable.
FIG. 8C shows a modification 3 in which a recess is formed in the separator 7. In this case, the curved portion may or may not be formed on the outer peripheral portion of the inner bottom surface of the concave portion of the separator 7. The concave portion of FIG. 8C is formed by the depression of the contact portion with the separator 7 and its peripheral portion by the compressive force of the electrode 5. As the material of the separator 7 that is depressed by the pressure of the electrode 5 in this manner, for example, a nonwoven fabric, a cellulosic material, glass fiber, or the like can be used. However, the depression of the separator 7 is not formed by the pressure of the electrode 5, but a depression is formed in the separator 7 in advance, and the electrode 5 may be brought into contact with the bottom 7a.

8B and 8C show the case where the wall portion 7b of the separator 7 is formed at the same height as the thickness of the electrode 5, the height of the wall portion 7b is as follows. It is also possible to make it lower than the thickness of the electrode 5.
That is, when the thickness of the electrode 5 is m1, the height m2 of the wall 7b is m2 ≦ m1, for example, m2 = (1/2) m, (2/3) m, (1/4). ) M or (1/5) m.

FIG. 9 is a diagram for explaining another modification 4 with respect to the first embodiment and modifications 1 and 2 thereof, and the second embodiment and modifications 1 and 2 thereof.
FIG. 9A is a diagram (top view) showing a state in which the basic shape separator 7 disposed on each step portion 51 described in FIGS. 4 and 5 is viewed from above. As shown in FIG. 9A, the basic separator 7 has a shape corresponding to the shape of the recess 13, that is, a rectangular shape.
On the other hand, in the separator 7 according to the modified example 4, a communication portion (communication means) that connects the electrode 5 side and the electrode 6 side in the recess 13 is provided. This communication part is for venting the gas that has entered the lower side of the separator 7 when the electric double layer capacitor is formed.
As the communicating portion, a notch 7d is formed in the corner of the separator 7 as shown in FIGS. 9B and 9C, and a through hole 7e for venting gas is formed in the corner as shown in FIG. 9D. May form.
When the separator 7 according to the fourth modification is disposed on the step portion 51, the communication portion (the notch 7 d and the through hole 7 e) is formed at a position shifted from the step portion 51 (a position not overlapping the step portion 51). .

Although FIG. 9B shows the notch 7d formed by C chamfering at one place and FIG. 9C at the four corners, they may be formed by R chamfering. Moreover, you may form the notch 7d by C chamfering or R chamfering in two places (two parallel corners and two diagonal corners).
FIG. 9D shows a case where a through hole 7e for venting gas is formed at one place. In FIG. 9D, the through hole has a circular cross section, but the cross section may have another shape such as an ellipse, a square, or a triangle. Further, similarly to the notch 7d, any of two places, three places, and four places may be used. In the case of two places, two parallel corners or two opposite corners may be used.
In addition, although each communication part shown in FIG. 9 was formed in the corner of the separator 7, you may make it provide a notch in any one part, or a through-hole.

  In addition, it is also possible to set it as the separator 7 which combined the modification 3 and the modification 4. That is, it is possible to form both the wall portion 7 b and the communication portion in the separator 7. In this case, any of the examples described in the modification 3 and any of the examples described in FIG. 4 may be combined.

The following effects can be obtained by the embodiment and the modification described above.
(1) By forming the concave container 2 by laminating sheet materials, the stepped portion 51 can be easily formed in the concave portion 13 that houses the electrodes 5 and 6.
(2) By providing the step portion 51 in the recess 13, the internal structure of the concave container 2 is made two steps, and the end of the separator 7 is always in contact with the upper surface of the step portion 51, so 5 and 6 can be completely separated, and even if the separator 7 is displaced, it can be prevented from being short-circuited.
(3) In the first modification of the first embodiment, the end of the separator 7 is sandwiched between the electrode 5 and the step portion 51 even if the separator 7 contracts due to heat or the like. Short circuit can be reduced.
(4) Since the short circuit between the electrode 5 and the electrode 6 can be effectively suppressed, the yield of the electric double layer capacitor 1 can be improved.
(5) Since the concave container 2 has an intermediate surface parallel to the lower surface between the upper surface where the recess 13 is open and the lower surface, the intermediate surface Can be used for installing the separator 7.

The following configurations can be obtained by the embodiment and the modification described above.
The concave container 2 is formed by laminating the sheet materials 41 to 44, and the hollow portion formed by the concave portion 13 has the step portion 51 on the inner wall, so the sheet material is laminated and the step portion is formed on the inner wall. It functions as a container having a hollow portion.
Since the separator 7 is placed on the upper surface of the stepped portion 51 and the concave container 2 is divided into two parts, the separator 7 is placed in contact with the stepped surface of the stepped portion and separates the hollow portion into two regions. Is functioning as
The electrode 5 functions as a first electrode installed in a region on one side of the separator, and the electrode 6 functions as a second electrode installed in a region on the other side of the separator.
The metal layer 15, the bonding metal layer 8, the metal layer 9, and the terminal 10 are connected to the first electrode and function as a first conductor that conducts to the outside of the container. The metal layer 11 and the terminal 12 are , Function as a second conductor connected to the second electrode and conducting to the outside of the container.
In addition, the electrolyte sealed in the recess 13 functions as an electrolyte in contact with the first electrode and the second electrode.

  In Modification 1 of the first embodiment, since the separator 7 is sandwiched and fixed between the step portion 51 and the electrode 5, at least a part of the end portion of the separator includes the step surface and the first portion. It is sandwiched and fixed between electrodes.

  The step 51 can be formed on the entire inner wall of the recess 13 and the end of the separator 7 can be fixed over the entire circumference with the electrode 5 and the step 51. In this case, the end of the separator And is fixed by being sandwiched between the step surface and the first electrode.

In addition, the size of the separator 7 satisfies the formula (1), so that the separator 7 is movable more than the maximum value of the movable distance on the step surface of the separator placed on the step surface. The length of the step surface in any direction is set large.
Furthermore, the electrode 5 is an electrode sheet composed of silicon oxide activated by metallic lithium (50 wt%), a conductive additive (40 wt%), and a polyacrylic acid binder (20 wt%). , An electrode sheet composed of an active material (85 wt%) having a spinel type crystal structure of lithium-manganese-oxygen element, a conductive assistant (10 wt%), and a PTFE binder (5 wt%), glass fiber It is also possible to provide a battery composed of the separator 7 made of 1 and 1M LiN (SO2CF3) 2 in PC and an electrolyte. Here, the size of the positive electrode and the negative electrode can be 1 mm long × 1.5 mm wide × 0.2 mm thick.

The electric double layer capacitor 1 can be used as, for example, a mobile phone memory or a clock backup power source.
In this case, the cellular phone exhibits predetermined functions such as an electronic component composed of the electric double layer capacitor 1, a power storage means for storing the battery of the main power supply and storing the electronic component at the same time, and a memory and a clock. Functions as an electronic device including other electronic components and power supply means for supplying power to the other electronic components using the stored charges, such as discharging the stored charges and supplying power to the memory or clock. doing.

DESCRIPTION OF SYMBOLS 1 Electric double layer capacitor 2 Concave container 3 Sealing plate 5 Electrode 6 Electrode 7 Separator 8 Bonding metal layer 9 Metal layer 10 Terminal 11 Metal layer 12 Terminal 13 Recess 15 Metal layer 16 Metal layer 21, 22 Through electrode 41-45 Sheet material 51 , 52 Step part 61 End part 100 Electric double layer capacitor 102 Concave container 103 Sealing plate 105 Negative electrode 106 Positive electrode 107 Separator 108 Bonding metal layer 109 Metal layer 110 Negative electrode terminal 111 Metal layer 112 Positive electrode terminal 113 Recessed part 115 Metal layer

Claims (6)

A container formed by laminating sheet materials, a stepped portion is formed on the inner wall, and a hollow portion formed in a rectangular parallelepiped shape;
A separator that is installed in contact with the stepped surface of the stepped portion and is formed in a rectangular shape that separates the hollow portion into two regions;
A first electrode installed in a region on one side of the separator;
A second electrode installed in a region on the other side of the separator;
A first conductor connected to the first electrode and conducting to the outside of the container;
A second conductor connected to the second electrode and conducting to the outside of the container;
An electrolyte in contact with the first electrode and the second electrode;
Comprising
The electronic component according to claim 1, wherein the separator is formed with a communication portion at four corners for communicating the first electrode side and the second electrode side in the hollow portion. The electronic component according to claim 1 , wherein the communication portion has a notch shape. 3. The electronic component according to claim 1, wherein at least a part of an end of the separator is fixed by being sandwiched between the step surface and the first electrode. End of the separator, either one of claims of claims 3 that claim 1, characterized in that is fixed by being sandwiched between the first electrode and the stepped surface over the entire circumference Electronic components described in The length of the step surface in the movable direction is set larger than the maximum value of the movable distance on the step surface of the separator placed on the step surface. The electronic component according to any one of claims 1 to 4 . The electronic component according to any one of claims 1 to 5 , 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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