JP5731836B2 - Electrochemical cell with terminal and manufacturing method thereof - Google Patents

Description

  The present invention relates to a terminal-attached electrochemical cell having a small size and low internal resistance, and a method for producing the same.

  Electrochemical cells such as lithium secondary batteries and electric double layer capacitors are used for main power, auxiliary power for main power, memory and clock function backup in various small electronic devices such as mobile phones, PDAs and portable game machines. It is mainly used as a power source.

  Especially for main power supply, auxiliary power supply for main power supply, etc., especially in applications such as load leveling of the portable device, a current of several A is instantaneously discharged or a current of several tens of mA is discharged for several seconds. Thus, operations such as driving the motor, blinking the light emitter, vibrating the piezoelectric body, and generating radio waves are performed. Therefore, in these electrochemical cells, the capacity (approx. Tens of mF to 1F) suitable for the above-mentioned use and an internal resistance value of several hundred mΩ, preferably 100 mΩ or less are required. A low resistance metal such as aluminum or copper is used as a material for the terminal. Further, when mounting on a circuit board, measures such as formation of a metal terminal that is easy to solder and protection of a connection portion have been taken so as not to cause resistance due to contact failure.

  Conventionally, the positive electrode terminal is composed of at least two kinds of metal partial clad materials, the interface between one metal and the other metal of the partial clad material is covered with an adhesive film, and the positive electrode lead portion and the positive electrode terminal are ultrasonicated. By welding, it is supposed to provide a highly reliable polymer electrolyte battery in which the positive electrode terminal is not broken by ultrasonic welding (for example, Patent Document 1).

  The positive electrode lead terminal is a strip-shaped clad plate including a nickel region formed on at least one surface or both surfaces of the connection allowance and an aluminum region, and the negative electrode lead terminal is formed on at least the connection allowance on one surface or both surfaces. By using a strip-like clad plate containing a nickel region and a copper region, a battery having excellent positive and negative lead terminals that is excellent in strength and corrosion resistance, can be easily soldered and spot welded, etc. It is supposed to be provided (for example, Patent Document 2).

JP 2001-126709 A JP 2004-39651 A

  By the way, in recent years, further improvement in the efficiency of the mounting process has been desired, and it has been desired that the electrochemical cell for the above-mentioned use also supports reflow automatic mounting. However, the electrochemical cells in Patent Document 1 and Patent Document 2 do not correspond to reflow mounting, and are constituted by an exterior body having a very low heat resistance such as a laminate film. Also, the terminals drawn out are not suitable for automatic reflow mounting because they are made of a soft metal material such as aluminum or copper.

  For this reason, mounting of this capacitor is unavoidable by soldering or the like after mounting other components by reflow processing. Moreover, since the exterior body is a laminate film, the drop impact characteristics after mounting are not satisfactory.

  Therefore, in order to produce an electrochemical cell with terminals that can be used for reflow automatic mounting in the above load leveling application, it is used as a material for small coin-type cells, as in the case of reflowing in a backup application cell. If stainless steel is used as an exterior body or terminal, it is excellent in heat resistance and durability at high temperatures, so that reflow mounting is possible. However, since stainless steel has a resistance value 10 times higher than that of aluminum or copper, it increases the internal resistance value of the cell.

For example, the resistance value of an external terminal manufactured by bending a stainless steel plate having a long side of 8 mm, a width of 2 mm, and a thickness of 0.15 mm is calculated as follows.
(Resistance value) = (resistivity) × ((long side) / (width × thickness))
= 7.2 × 10 ⁻⁷ Ωm × (8 × 10 ⁻³ m / (2 × 10 ⁻³ m × 0.15 × 10 ⁻³ m))
= 19.2mΩ
In the structure in which the external terminals are provided in a pair of positive and negative electrodes, the resistance value is close to 40 mΩ only with the external terminals. On the other hand, unlike a small coin type in which the internal resistance of the cell is about several hundred Ω, in the case of an electrochemical cell used for leveling the load of a portable device, the internal resistance is several hundred mΩ, preferably 100 mΩ or less. A value is determined. In particular, when an internal resistance of several tens of mΩ or less is required, only the external terminal occupies most of the resistance value.

  As described above, it has been a problem to produce an external terminal having a small resistance value and capable of maintaining durability at a high temperature during reflow mounting for an electrochemical cell that can be reflow mounted.

  The present invention has been made in view of such circumstances, and its purpose is to reduce the contribution of the resistance of the external terminal to the internal resistance of the cell, and to easily and firmly connect to the circuit board. It is an object of the present invention to provide an electrochemical cell with a terminal having low internal resistance and capable of surface mounting by automatic reflow mounting, which has heat resistance and durability at.

The present invention provides the following means in order to solve the above problems.
Terminal with the electrochemical cell according to the present invention comprises one or more terminals which are insulated fixed glass hermetic seal on one plane of the metal outer body having two plane faces, the interior of the outer body is accommodated power generation elements and an electrolyte, wherein a single cell positive electrode and the negative electrode is connected the terminal or the in the outer package and electrically the power generating element, and a fixed terminal connected to the other of the plane of said outer body, said An external terminal electrically connected to the power generation element via a terminal, wherein the fixed terminal includes a bottom surface portion that is a mounting surface with a circuit board, and the external terminal terminal is provided with a bottom portion is a mounting surface of the terminal connecting portion and the circuit board to be connected to the terminals, a first material said a metal terminal and the like, lower resistivity than said first material It has a multilayer structure consisting of the second material The features.

The manufacturing method of the electrochemical cell with a terminal which concerns on this invention is a metal exterior provided with one or more terminals insulated and fixed by the glass hermetic seal to one plane of the metal exterior body which has two opposing planes. and the outer body preparing step of preparing a case and a lid member constituting the body, accommodating the power generation element into the interior of the outer body, a positive electrode and a negative electrode of the power generating element is connected to the terminal or the outer body, said case and a step of preparing a single cell by welding and said cover member, a step of connecting the fixed terminal on the other plane of the exterior body, a step of connecting the outer portions pin, the outer a step of sealing housing the electrolyte in the body part, a method for producing a terminal with an electrochemical cell Ru wherein the external terminal is the mounting surface of the terminal connecting portion and the circuit board to be connected to the terminal A bottom portion, and the terminal It characterized in that the first material is a kind of metal, a multi-layer structure consisting of a second material which has lower resistivity than said first material.

  In the present invention, as a material for the external terminal, a multilayer structure including a first material that is the same kind of metal as the terminal and a second material having a resistivity lower than that of the first material is used. It is done. In particular, the resistance value of the external terminal is reduced by the layer of the second material having a low resistivity as compared with the case where only the first material is used as the material of the external terminal. Further, since the first material is the same kind of metal as the terminal, the weldability between the external terminal and the terminal is also maintained.

  Further, in the present invention, since a highly heat-resistant member is used for a power generation element composed of a metal exterior body, a positive electrode, a negative electrode, a separator, and the like, the temperature of the cell during reflow and the internal pressure are increased. Since it can withstand the rise, changes in internal resistance and capacitance are suppressed to a slight range. Furthermore, since the terminal used in the electrochemical cell with terminal and the first material of the external terminal are of the same type, the shape is maintained by heating during reflow.

Electrochemical cell with terminals according to the present invention comprises one or more terminals which are insulated fixed glass hermetic seal in a single plane of metal outer package is parallelepiped-shaped, power generation elements inside the outer body And the electrolyte, the positive electrode and the negative electrode of the power generation element are connected to the opposing surface of the plurality of single cells electrically connected to the terminal or the exterior body and the one plane of the exterior body A fixed terminal, and an external terminal and a balance terminal electrically connected to the power generation element via the terminal, and each single cell is connected so that the one plane and the facing surface are substantially in the same plane. The terminal-attached electrochemical cell electrically connected in series via the balance terminal, wherein the fixed terminal includes a bottom surface portion that is a mounting surface with a circuit board, Across a single cell Is, the external terminal and the balanced terminals is provided with a bottom portion is a mounting surface of the terminal connecting portion and the circuit board to be connected to the terminal, and the first material is a metal of the terminal and the same type, the first It is characterized in that it has a multilayer structure composed of a second material having a resistivity lower than that of the above material.

Method for producing a terminal with an electrochemical cell according to the present invention, constitutes a metal outer body having one or more terminals which are insulated fixed glass hermetic seal in a single plane of metal outer body is rectangular parallelepiped and the outer body preparing step of preparing a case and a lid member, houses a power generation element inside the outer body, a positive electrode and a negative electrode of the power generating element is connected to the terminal or the outer body, the said casing lid A step of manufacturing a single cell by welding a member, a step of connecting a plurality of the single cells such that the one plane and the opposing surface are substantially the same plane, and the one of the exterior bodies . a step of connecting the fixed terminal on the opposed surfaces of the plane, and the step of connecting the outer portions pin, a step of connecting the balance terminal and the terminal or the exterior body, inside the outer body Contains and seals electrolyte And that step a method for producing a terminal with an electrochemical cell Ru wherein the external terminal and the balanced terminals is provided with a bottom portion is a mounting surface of the terminal connecting portion and the circuit board to be connected to the terminal, It is a multilayer structure composed of a first material that is the same kind of metal as the terminal and a second material having a resistivity lower than that of the first material .

  In the present invention, as a material for the external terminal and the balance terminal, a multilayer structure including a first material that is the same kind of metal as the terminal and a second material having a lower resistivity than the first material. The body is used. In particular, the second material layer having a low resistivity reduces the resistance values of the external terminal and the balance terminal as compared with the case where only the first material is used as the material of the external terminal and the balance terminal. Moreover, since the first material is the same type of metal as the terminal, the weldability between the external terminal, the balance terminal, and the terminal is also maintained.

  Further, in the present invention, since a highly heat-resistant member is used for a power generation element composed of a metal exterior body, a positive electrode, a negative electrode, a separator, etc., each single cell has a temperature rise during reflow. In addition, the internal resistance value and capacity of the electrochemical cell can be suppressed to a slight range. Furthermore, since the first material of the terminal used in the electrochemical cell with terminal, the external terminal, and the balance terminal is the same type, the shape is maintained by heating during reflow.

Electrochemical cell with terminals according to the present invention, the multilayer structure, said first material, said second material entirely or partially disposed relative to the first material, which is composed of and wherein the structure der Rukoto.

  In the present invention, the external terminal and the balance terminal have a multilayer structure made of the first material and the second material. The first material and the second material are in contact with each other over the entire surface or the second material.

  In particular, when the second material is partially layered and has a region where only the first material exists, the terminal and the first material of the same material as the terminal are welded or the like. Therefore, welding with the same kind of metal without using the second material becomes possible, so that the welding becomes stronger.

Electrochemical cell with terminals according to the present invention, prior Symbol first material is formed from stainless steel, the second material is characterized in that it is formed from copper or an alloy containing copper.

Method for producing a terminal with an electrochemical cell according to the present invention, the use of those prior Symbol stainless with those formed by a first material, which is formed of an alloy containing copper or copper as the second material It is characterized by.

  In the present invention, the same kind of stainless steel as the terminal is used as the first material of the external terminal and the balance terminal. Stainless steel is suitable for reflow mounting because of its excellent heat resistance and durability. Moreover, since heat conductivity is low and it is hard to radiate heat, the energy input at the time of welding with a terminal is suppressed. In particular, in laser spot welding, the irradiation output is suppressed, and since the light absorptance is high in the wavelength region (1064 nm) of a YAG laser generally used as laser welding, welding is performed efficiently.

Moreover, copper or an alloy containing copper is used as the second material. Since the resistivity of copper at 293K is 1.68 × 10 ⁻⁸ Ωm, which is one tenth or less of the resistivity of stainless steel (7.2 × 10 ⁻⁷ Ωm), when used as a material for an external terminal, The resistance value is greatly reduced. Furthermore, copper is a material used for wiring of a circuit board, and has good wettability during soldering, and thus is suitable as a material for an external terminal in contact with the circuit board.

  According to the present invention, the multi-layer structure made of stainless steel and copper having the above characteristics is used as the external terminal and the balance terminal, so that the same heat resistance and durability as when formed with stainless steel are maintained. The external terminal and the balance terminal have a low resistance value. Also, the weldability with the terminal is good, and a good connection with the circuit board is possible at the time of surface mounting, and each is firmly connected.

  In the electrochemical cell with a terminal according to the present invention, the cross section of the external terminal is a crank shape having two horizontal portions and one upright portion, a U shape, a flat plate shape, or an L shape. Features.

  In the present invention, when the external terminal has a crank shape having two horizontal portions and one upright portion, alignment between the external terminal and the terminal is easy, and connection work can be simplified. When the external terminal is L-shaped, the bottom surface of the L-shaped external terminal is parallel to the bottom surface of the exterior body even when the terminal is not parallel to the bottom surface of the exterior body. Since it can connect to the said terminal, it can connect in parallel with the circuit board which mounts the electrochemical cell with a terminal. Furthermore, depending on the shape of the exterior body, a flat plate shape that is not bent into each of the above shapes is possible.

  Furthermore, when the external terminal is U-shaped, the connection work is simple as in the case of the crank shape, and the horizontal part connected to the circuit board is folded, so that the extension of the cell terminal Since the direction dimension can be shortened, it is practically preferable. In this case, when mounting on the circuit board, it is necessary to design the pattern so that the pattern of the circuit board and the bottom surface of the exterior body do not come into contact with each other.

  In the electrochemical cell with a terminal according to the present invention, the balance terminal has a crank-shaped or U-shaped cross section having two horizontal portions and one upright portion, a flat plate shape, a U-shaped shape, or an open end. It is the shape which made the U-shape which has a horizontal part in reverse.

  In the present invention, when the balance terminal has a crank shape having two horizontal portions and one upright portion, the balance terminal and the terminal or the exterior body can be easily aligned and connection work can be simplified. . Further, when the balance terminal has a U-shape or a shape in which a U-shape having a horizontal portion at the open end is turned upside down, the bottom surface of the balance terminal even when the terminal is not parallel to the bottom surface of the exterior body. Can be connected to the terminal so as to be parallel to the bottom surface of the exterior body. Thereby, it can connect in parallel with the circuit board which mounts the electrochemical cell with a terminal. Furthermore, depending on the shape of the exterior body, a flat plate shape that is not bent into each of the above shapes is possible.

  Furthermore, when the external terminal is U-shaped, the connection work is simple as in the case of the crank shape, and the horizontal part connected to the circuit board is folded, so that the extension of the cell terminal Since the direction dimension can be shortened, it is practically preferable. In this case, when mounting on the circuit board, it is necessary to design the pattern so that the pattern of the circuit board and the bottom surface of the exterior body do not come into contact with each other.

Electrochemical cell with terminals according to the present invention is characterized in that said terminal connecting portion is provided with a plurality of weld points that by the laser spot welding.

Method for producing a terminal with an electrochemical cell according to the present invention has a front Kigaibu pin, contact and said pin, by irradiating a laser beam toward the first material of the outer end terminal, wherein and said pin and an external terminal was welded by laser spot welding, and wherein the welding at a plurality of welding points for each weld point.
In the method for manufacturing an electrochemical cell with a terminal according to the present invention, the external terminal and the balance terminal are in contact with the terminal, and laser light is directed toward the first material of the external terminal and the balance terminal. By irradiating, the external terminal, the balance terminal, and the terminal are welded by laser spot welding, and welding is performed at a plurality of welding points for each welding point.

  In the present invention, laser spot welding is employed for welding the external terminal and balance terminal to the terminal or the exterior body. In laser spot welding, the spot diameter, welding power, and irradiation time can be easily adjusted, and a necessary and sufficient penetration depth can be formed between workpieces to be joined. In addition, it is also characterized by little thermal influence outside the vicinity of the welding target region, and is suitable for manufacturing a small electrochemical cell with a terminal. In addition, two or more welding points are formed at intervals in the welding location. As a result, for external forces in handling and mounting on jigs in each process after welding, handling and impact at the time of mounting by automatic mounting machine on circuit board, drop impact after being incorporated in electronic equipment, etc. It is possible to have excellent durability.

  In particular, in a cell using a metal outer package as in the present invention, the weight is about 2 to 3 times larger than that of an aluminum laminate package or the like of the same size. When the number of welding points at each welding point is one, there is a possibility that the external terminal or the like is peeled off at the welding point. This can be avoided by connecting a plurality of welding points with a space.

  Furthermore, the internal resistance value of the electrochemical cell with terminals is not only the resistance value determined from the power generation element and electrolyte housed in the exterior body, but also leads, terminals, external terminals and balance terminals connected to the power generation element. The material, dimensions, connection, or joining method of the material greatly contributes. Therefore, since laser spot welding is used for the connection between the external terminal and the terminal and the connection between the balance terminal and the terminal, a sufficient penetration depth can be formed at the welding point, and atoms of each material are diffused and joined together. The junction resistance value is sufficiently low, 1 mΩ or less.

  Here, when welding is performed by irradiating laser light, the first material is irradiated with light. Since the second material has a lower resistivity than the first material, the thermal conductivity tends to be high. Therefore, when the second material is irradiated with laser light, the required irradiation output becomes very large due to the diffusion of thermal energy as compared with the case where the second material is irradiated. When irradiating laser light, contact the terminal or exterior body with the surface of the second material, and irradiate from the first material side, so that the irradiated part can be efficiently melted and welded firmly. Can do.

  Further, when the external terminal or the balance terminal includes a region where the second material is partially layered and only the first material is present, the first material and the terminal are made of the same kind of metal. By laser spot welding with each other, it is possible to connect more firmly.

  The electrochemical cell with a terminal according to the present invention is characterized in that a surface having a connection portion between the terminal and the external terminal intersects the substrate surface perpendicularly.

  In the present invention, when the surface having the connection portion between the terminal and the external terminal intersects perpendicularly to the substrate surface, the bottom surface of the external terminal is installed horizontally even when the terminal is inclined downward. be able to. Thereby, it can connect in parallel with the circuit board which mounts the electrochemical cell with a terminal.

  According to the present invention, the contribution of the resistance of the external terminal to the internal resistance of the cell is reduced, it can be easily and firmly connected to the circuit board, and has low heat resistance and high temperature resistance and durability. An electrochemical cell capable of surface mounting by automatic reflow mounting can be obtained.

1 is an external perspective view of an electric double layer capacitor showing a first embodiment according to the present invention. It is an external appearance perspective view of the external terminal which comprises the electric double layer capacitor shown in FIG. It is a figure which shows the structural example of the laser spot welding of the external terminal shown in FIG. It is a schematic diagram of the connection form of the external terminal and terminal which comprise the electric double layer capacitor shown in FIG. It is an external appearance perspective view of the fixed terminal which comprises the electric double layer capacitor shown in FIG. It is an external appearance perspective view of the electric double layer capacitor which shows 2nd Embodiment concerning this invention. It is an external appearance perspective view of the balance terminal which comprises the electric double layer capacitor shown in FIG. It is an external appearance perspective view of the electric double layer capacitor which shows 3rd Embodiment concerning this invention. It is an external appearance perspective view of the electric double layer capacitor which shows 4th Embodiment concerning this invention.

(First embodiment)
Hereinafter, embodiments according to the present invention will be described with reference to FIGS. 1 to 5. In the present embodiment, an electric double layer capacitor will be described as an example of an electrochemical cell. In addition, it is also possible to configure a primary battery or a secondary battery.

  As shown in FIG. 1A, the electric double layer capacitor 1 of the present embodiment includes a metal box-shaped exterior body 2, a pair of terminals 3 fixed to this by an insulating member 4, and external terminals 5. And a fixed terminal 6, a power generation element 16 composed of a positive electrode, a negative electrode and a separator, and an electrolyte E. The positive electrode and the negative electrode are electrically connected to the terminal 3 inside the capacitor. In FIG. 1A, the case 12 is shown as a transparent body in order to show the inside of the exterior body 2.

  FIG. 1A is an external perspective view of the electric double layer capacitor 1 with a terminal. FIG. 1B is a cross-sectional view of the terminal-attached electric double layer capacitor 1 along the line A-A ′ shown in FIG. FIG. 1C is an external perspective view shown from the back of FIG.

  In the present embodiment, the metal exterior body 2 is made of stainless steel, specifically, SUS316L, and is a small rectangular container having a long side of 15 mm, a short side of 10 mm, a height of 3 mm, and a case thickness of 0.3 mm. It is. The exterior body 2 is composed of a plurality of constituent members. Specifically, the case 12 and the lid member 11 are fixed so as to close the opening of the case 12 by seam welding or the like, and the inside is airtight. Is sealed.

  The pair of terminals 3 are fixed to the lid member 11 with an interval in the lateral width direction. This terminal 3 is a solid round bar thin wire formed of stainless steel (SUS316L) in the same manner as the lid member 11, and is disposed so as to penetrate the lid member 11. The pair of terminals 3 have a hermetic seal structure made of an insulating member 4 obtained by baking glass, and are hermetically fixed to the lid member 11.

  In particular, both the exterior body 2 and the terminal 3 are made of stainless steel, which has corrosion resistance to the electrolyte E, and has high heat resistance and durability, so that a reflow mountable and highly reliable cell is manufactured. can do.

  The main material of the external terminal 5 of the present embodiment is produced by cold-welding the first material 51 made of stainless steel (SUS304) and the second material 52 made of copper over the entire surface. The clad material has a total thickness of 0.2 mm, a first material thickness of 0.15 mm, and a second material thickness of 0.05 mm. This base material is punched into a flat plate and bent into a crank shape to form an external terminal 5, a bottom surface portion 5b for connecting to a circuit board, and a terminal connecting portion 5a connected to the upper portion of the terminal Is formed. The external terminal 5 and the upper part of the terminal 3 are connected by laser spot welding. In particular, as shown in FIG. 1, by providing a plurality of welding points 25 by laser spot welding, the connection is mechanically strong, and the electrical resistance value by the connection is extremely low. Can be suppressed.

The external terminal 5 is formed of a flat plate having a length of 8 mm and a width of 2 mm. When the first material 51 and the second material are entirely in pressure contact, the resistance value is calculated as follows. Compared to the case of stainless steel, it is greatly reduced.
(Resistance value of the first material) = (resistivity) × ((long side) / (width × thickness))
= 7.2 × 10 ⁻⁷ Ωm × (8 × 10 ⁻³ m / (2 × 10 ⁻³ m × 0.15 × 10 ⁻³ m))
= 19.2mΩ
(Resistance value of second material) = (resistivity) × ((long side) / (width × thickness))
= 1.68 × 10 ⁻⁸ Ωm × (8 × 10 ⁻³ m / (2 × 10 ⁻³ m × 0.05 × 10 ⁻³ m))
= 1.3mΩ
(Resistance value) = 1 / (1 / (resistance value of the first material) + 1 / (resistance value of the second material))
= 1.3mΩ
In the external terminal 5, the first material 51 and the second material 52 are entirely layered. In particular, as shown in FIG. 2, the second material 52 is composed of the first material 51. There may be a layer of only the first material 51 in contact with the first material 51. In this case, as shown in FIG. 3, the terminal connection portion 5 a is composed of only the first material 51 and is laser spot welded to the upper portion of the terminal 3. Thereby, welding between the same kind of metals becomes possible, and since a plurality of welding points 25 by laser spot welding are provided, the connection is strong.

  As for the shape of the external terminal 5, in addition to the crank shape shown in FIG. 2 (a), a U-shape, an L-shape, a flat plate shape, etc., for surface mounting as shown in FIGS. 2 (b) to 2 (d). Various suitable shapes can be applied.

  In FIG. 4, (a) shows the connection form of the respective external terminals 5 having a crank-shaped cross section, (b) a U-shape, (c) an L-shape, and (d) a rectangular shape. Various connection forms as shown in FIGS. 4A to 4D are possible for the external terminal 5 and the terminal 3 shown in FIG. In FIG. 1 (a), a crank-shaped external terminal 5 is disposed so as to cover the terminal 3, and is laser spot welded from above, but as shown in FIG. 4 (a), the external terminal 5 However, each upright portion may be shortened while maintaining the crank shape, and the terminal connection portion 5a may be connected to the lower side of the terminal 3. Further, as shown in FIG. 4B, a connection between the U-shaped external terminal 5 and the terminal 3 may be used. Alternatively, as shown in FIG. 4C, the L-shaped external terminal 5 and the end face of the terminal 3 may be connected, or may be connected to the side face of the terminal 3 although not shown. Furthermore, as shown in FIG. 4D, when the exterior body is thin, it is also possible to use a flat plate-like external terminal 5.

  In FIG. 5, (a) shows a fixed terminal 11 having an L-shaped cross section, (b) a U-shape, and (c) a rectangular shape. As shown in FIG. 5A, the fixed terminal 6 of the present embodiment is formed by bending a stainless steel (SUS304) plate having a thickness of 0.15 mm into an L-shaped structure, and is connected to a circuit board. Bottom surface portion 6 b and an upright portion 6 a for connecting to the exterior body 2. Regarding the shape of the fixed terminal 6, as shown in FIG. 5, in addition to the L shape, various shapes such as a U shape and a flat plate shape are possible according to the structure of the exterior body and the arrangement of the circuit board. . The fixed terminal 6 is connected to the exterior body 2 by laser spot welding.

  The sealing plug 9 is used to block an electrolyte injection hole provided at one location of the outer package 2 shown in FIG. Further, since the sealing plug 9 is in contact with the electrolyte E, the sealing plug 9 is formed of a disk made of stainless steel (SUS316L) of the same quality as the exterior body 2.

  The heights of the bottom surface portion 5b of the external terminal 5 and the bottom surface portion 6b of the fixed terminal 6 are equal so as to be mounted horizontally on the circuit board. The assumed horizontal plane formed by these bottom surface portions, that is, the horizontal plane formed by the surface of the circuit board to be mounted is designed and disposed so as to be lower than the bottom surface of the exterior body. It is preferable that the clearance H between the assumed horizontal plane and the bottom surface of the exterior body shown in FIG. However, when the mounting height as a surface mounting component is limited, the numerical value of this clearance can be adjusted.

  The power generation element 16 is housed inside the exterior body 2. The power generation element 16 is provided with a positive electrode and a negative electrode with a separator interposed therebetween, and these are alternately stacked and manufactured by winding or stacking. The positive electrode and the negative electrode are made of a material that has corrosion resistance to the electrolyte E and can withstand a high temperature environment in the reflow mounting process. In the present embodiment, an aluminum current collector is used in which a positive electrode active material and a negative electrode active material made of activated carbon or the like are supported. In addition, a resin having mechanical strength and heat resistance is used for the separator. For the separator, glass fiber, ceramic porous body, and the like can be used in addition to the above-described resin.

  The electrolyte E is housed inside the hermetic outer package 2 and penetrates into the power generation element 16. In the present embodiment, an electrolytic solution in which a supporting salt is dissolved in a non-aqueous solvent having a high boiling point is used so as to withstand a high temperature environment in the reflow mounting process. Examples of the non-aqueous solvent include cyclic esters, chain esters, cyclic ethers, chain ethers, and the like. In the present embodiment, a single compound or a composite selected from solvents having a high boiling point such as γ-butyrolactone, propylene carbonate, and ethylene carbonate is used. Thereby, the pressure inside the exterior body 2 can be suppressed in a high temperature environment. In addition, as the supporting salt, among the various salts having durability against the reflow temperature, those having the optimum conductivity by the combination with the solvent are used.

  As the electrolyte E, in addition to the above electrolytic solution, a polymer electrolytic solution, an inorganic solid electrolyte, an ionic liquid, a room temperature molten salt, or the like can be used.

  The electric double layer capacitor 1 in which the power generating element 16 and the electrolyte E are accommodated in the above-described size has an internal resistance value lower than 100 mΩ. Accordingly, it can be suitably used as an auxiliary power source for a main power source in various electronic devices such as instantaneously discharging a current of several A or discharging a current of several tens of mA for several seconds. In addition, by providing excellent heat resistance, changes in electrical characteristics can be suppressed even when exposed to high temperatures during the reflow mounting process.

  Furthermore, the fabricated electric double layer capacitor 1 was heat-treated at a reflow temperature, then incorporated into a mobile phone, and a drop impact test was performed to drop it onto concrete from a height of 1.5 m. Even if it repeated below, the external terminal did not come off from the terminal, and the connection was maintained.

  Next, a method for manufacturing the electric double layer capacitor 1 configured as described above will be described below.

  The manufacturing method according to the present embodiment includes an exterior body manufacturing process, a process of storing a power generation element, a welding process of a fixed terminal and an external terminal, and a sealing process. Each of these steps will be described in detail.

  First, an exterior body manufacturing process for manufacturing the case 12 and the lid member 11 constituting the exterior body is performed. The case 12 is made by deep drawing of stainless steel. Here, the transfer process is gradually deepened and finally the sizing process is performed to precisely finish the opening surface of the case.

  On the other hand, the lid member 11 is first prepared by preparing a glass tablet (sintered product) for forming a hermetic seal, a thin rod for terminals, and a plate with a hole for the lid member. A glass tablet through which a thin rod is passed is attached to the hole of the plate with holes, and is placed on a firing jig for positioning them, and heat-treated in a firing furnace. In this manner, the lid member 11 having a pair of hermetic seal structures in which the terminals 3 are fixed by the insulating member 4 is produced.

  Next, a step of housing the power generation element 16 in the exterior body 2 is performed. First, the positive electrode, the negative electrode, and the separator which comprise the electric power generation element 16 are prepared, respectively. Then, a step of welding a pair of leads 17 to the positive and negative electrode current collectors is performed.

Subsequently, the positive and negative electrode current collectors to which the leads 17 are connected are alternately stacked with the separator interposed therebetween, and then the power generation element 16 is manufactured by winding, stacking, and the like. Subsequently, a pair of leads 17 are connected to the terminals 3 respectively. Thereby, the electric power generation element 16 and the cover member 11 are integrated. Furthermore, the power generation element 16 to which the lid member 11 is connected is pushed into the case 12, and the lid member 11 and the case 12 are seam welded to produce the exterior body 2.
At this point, the process of storing the power generation element is completed.

  Next, a process of welding the fixed terminal 6 to the exterior body 2 is performed. First, the fixed terminal 6 is prepared. Specifically, after nickel and gold are partially plated on a stainless steel flat plate, punching and bending are performed by a press or the like. Thereby, the fixed terminal 6 can be obtained.

  Then, the process of welding the upright part 6a of the fixed terminal 6 to the exterior body 2 by laser spot welding is performed. Specifically, the upright portion 6 a is overlaid on the bottom surface of the case 12. And YAG laser beam is irradiated from a perpendicular direction, and the upright part 6a and the exterior body 2 are welded. As a welding condition, for example, YAG laser light is irradiated to four rectangular peripheral portions of the upright portion 6a at an output of 1.2 kW and an irradiation time of 1.5 msec. By providing at least two to three or more welding points, the fixed terminal 6 and the exterior body 2 can be firmly connected.

  Next, a welding process for welding the external terminal 5 to the terminal 3 fixed to the exterior body 2 is performed. First, the external terminal 5 is prepared and prepared. Specifically, after the stainless steel plate material as the first material 51 and the copper plate material as the second material 52 are overlapped, the two plate materials are pressed and combined. Then, the pressed plate material is punched and bent by a press or the like. Thereby, the external terminal 5 can be obtained. The stainless steel plate material and the copper plate material may be pressed together over the entire surface, or the copper plate material may be partially pressed into the stainless steel plate material as shown in FIG. About how to combine board | plate materials, it can select freely according to design conditions, such as welding conditions with the terminal 3, and resistance of a terminal.

  Further, copper is easily corroded, and after the press-bonding process is performed so as to cover the second material 52 in order to improve the solder wettability during mounting and make the mounting on the circuit board easier. Nickel plating and gold plating are performed between any of the processes up to.

  Then, the process of welding the terminal connection part 5a of the external terminal 5 to the terminal 3 fixed to the exterior body 2 by laser spot welding is performed.

  Specifically, the terminal connection portion 5a of the external terminal 5 is overlaid on the terminal 3 by the arrangement as shown in FIG. Then, YAG laser light is irradiated from above toward the surface of the first material 51 to weld the terminal connection portion 5a and the terminal 3 together. Under the welding conditions described later, YAG laser light is irradiated to two adjacent points as indicated by the irradiation spot 25. In particular, by providing two or more welding points, the external terminal 5 and the terminal 3 can be mechanically firmly connected, and can be electrically connected with a sufficiently low connection resistance. In the present embodiment, the external terminal 5 is disposed so as to cover the terminal 3. The external terminal 5 may be shortened in the upright portion while maintaining the crank shape, and the terminal connection portion 5 a may be connected to the lower side of the terminal 3.

  An example of adjustment of welding conditions between the terminal 3 and the external terminal 5 is shown. In the case of using the external terminal 5 in which the first material 51 and the second material 52 are press-contacted over the entire surface, the irradiation time is fixed to 1.5 msec, the peak output is changed, and the terminal 3 side at the welding location The penetration depth was measured by cross-sectional observation. As shown in Table 1, in this example, the penetration was good in the range of 1.3 to 1.8 kW, and welding was possible in this output range. On the other hand, welding was performed at an output exceeding 2.0 kW, but sputtering occurred because the output was too strong, and there was almost no penetration. For this reason, in this embodiment, welding is performed at 1.3 kW, which is the minimum output in a suitable output range.

  Further, in the case where the external material is partially formed of the second material as shown in FIG. 2, only the first material 51 of the terminal connection portion 5a is formed as shown in FIG. The formed portion is overlapped with the terminal 3 and welded. In this case, welding is performed with the same kind of metal between stainless steels. For example, welding is performed under the same conditions as the welding conditions between the fixed terminal 6 and the exterior body 2, an output of 1.2 kW, and an irradiation time of 1.5 msec. On the other hand, in the case of the external terminal 5 having a structure in which the first material and the second material are in pressure contact with each other, since the copper used for the second material is also melted together, it differs as described above. It becomes welding conditions.

  Subsequently, sealing of the exterior body 2 in which the electrolyte E and the power generation element 16 are housed is performed by enclosing the electrolyte E in the exterior body 2 and welding the case 12 and the sealing plug 9. Stop process.

This sealing step will be specifically described.
First, in the present embodiment, an electrolyte solution made of a supporting salt dissolved in a nonaqueous solvent is used as the electrolyte E, and the inside of the exterior body 2 is formed from an injection hole formed in one place of the case 12 of the exterior body 2. Inject a fixed amount. In order to inject the predetermined amount, the work of defoaming the electrolyte, the work of depressurizing the inside of the exterior body, and the work of pressurizing are performed to sufficiently penetrate the positive and negative electrode materials of the power generation element. In the case of this example, about 0.2 g of electrolyte was injected.

  Thereafter, the electrolytic solution adhering to the opening of the injection hole is wiped off, and the sealing plug 9 is disposed in the injection hole. Then, the outer periphery of the sealing plug 9 is sealed by seam welding.

  As a result, the terminal-attached electric double layer capacitor 1 shown in FIG. 1 in which the electrolyte E and the power generation element 16 are housed in the exterior body 2 can be obtained.

  In addition, the welding conditions shown by the said manufacturing process are examples, and conditions, such as an output and irradiation time, are not limited to this but can be implemented. However, in the welding process of the terminal 3 and the external terminal 5, the insulating member 4 made of glass having a hermetic structure may be cracked by a thermal shock caused by laser irradiation, leading to leakage. It is desirable to carry out welding in an appropriate range in which the crack does not occur.

(Second Embodiment)
Next, a second embodiment according to the present invention will be described with reference to FIGS. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 6, the electric double layer capacitor 10 with a terminal of this embodiment is a series connection body of two small electric double layer capacitor single cells, and each single cell is a metal box-shaped outer package. 2, a pair of terminals 3 fixed thereto by an insulating member 4, a power generation element composed of a positive electrode, a negative electrode and a separator, and an electrolyte. The positive electrode and the negative electrode are electrically connected to the terminal 3 inside the exterior. Connected.

  The single cells are arranged side by side so as to align the surfaces of the side surfaces that form the exterior body 2 and the terminals, and are fixed via the connecting plate 8. Furthermore, the external terminal 5 and the balance terminal 7 are connected in series.

  In the present embodiment, as shown in FIG. 6, the side surfaces including the terminals 3 of the single-cell exterior bodies 2 are aligned, and the side surfaces orthogonal to the side surfaces are in close contact and juxtaposed, with the connecting plate 8 interposed therebetween. Each single cell is mechanically connected.

  Further, out of a total of four terminals 3, the outermost two terminals are connected to an external terminal 5 that is positive and negative, and the balance terminal 7 is connected to the remaining two adjacent terminals.

  As for the main material of the external terminal 5 in this embodiment, as in the first embodiment, the first material 51 formed of stainless steel and the second material 52 formed of copper are cold-welded over the entire surface. The clad material thus produced has a total thickness of 0.2 mm, a first material thickness of 0.15 mm, and a second material thickness of 0.05 mm. This base material is punched into a flat plate and bent into a crank shape to form an external terminal 5. As shown in FIG. 2, a bottom surface portion 5b for connection to a circuit board and an upper portion of the terminal are formed. A terminal connection portion 5a to be connected is formed.

  When the external terminal 5 is formed of a flat plate having a length of 8 mm and a width of 2 mm in which the first material 51 and the second material 52 are pressed together over the entire surface, as in the first embodiment, the resistance value is It is calculated as 1.3 mΩ, which is greatly reduced as compared with the case where it is made of stainless steel (19.2 mΩ).

  As for the external terminal 5, as in the first embodiment, the first material 51 and the second material 52 are entirely layered, and the second material 52 is the first material. There may be a layer in contact with the first material 51 and only the first material 51. In this case, the terminal connecting portion 5a is composed of only the first material 51 and is laser spot welded to the upper portion of the terminal 3. As a result, welding between the same kind of metals becomes possible, and a plurality of welding points by laser spot welding are provided, so that the connection is strong.

  The main material of the balance terminal 7 is a clad material produced by cold-welding a first material 71 made of stainless steel (SUS304) and a second material 72 made of copper over the entire surface. The total thickness is 0.2 mm, the thickness of the first material is 0.15 mm, and the thickness of the second material is 0.05 mm. This base material is punched into a flat plate and bent into a crank shape to form a balance terminal 7. As shown in FIG. 7, a bottom surface portion 7b for connecting to a circuit board and an upper portion of the terminal are formed. A terminal connection portion 7a to be connected is formed. The balance terminal 7 and the upper part of the terminal 3 are connected by laser spot welding. In particular, by providing a plurality of welding points by laser spot welding, as described above, the mechanical connection becomes strong and the electrical resistance value due to the connection can be suppressed to an extremely low value. Is possible.

  When the balance terminal 7 shown in FIG. 7 is formed from a flat plate having a length of 8 mm and a width of 6 mm in which the first material 71 and the second material 72 are pressed together over the entire surface, the resistance value is the external value shown in FIG. As in the case of the terminal 5, it is calculated as 0.4 mΩ, which is greatly reduced as compared with the case of being made of stainless steel (6.4 mΩ).

  Similar to the external terminal 5, the balance terminal 7 has a first material 71 and a second material 72 that are entirely layered, and in particular, as shown in FIG. However, the first material 71 may be partially in contact with the first material 71 alone. In this case, the terminal connection portion 7a is composed of only the first material 71 and is laser spot welded to the upper portion of the terminal 3. As a result, welding between the same kind of metals becomes possible, and a plurality of welding points by laser spot welding are provided, so that the connection is strong.

  As for the shape of the external terminal 5, as shown in FIG. 5, in addition to the crank shape shown in FIG. 2A, a U shape, an L shape, a flat plate shape, etc. Various shapes suitable for surface mounting can be applied as shown in FIG.

  Similarly, the balance terminal 7 has a U-shape, a flat plate shape, or a U-shape having a horizontal portion at the opening, in addition to the crank shape as shown in FIG. Various shapes suitable for surface mounting can be applied, for example, as shown in FIGS.

  Various connection forms as shown in FIGS. 4A to 4D are possible for the external terminal 5 and the terminal 3 shown in FIG. In FIG. 1 (a), a crank-shaped external terminal 5 is disposed so as to cover the terminal 3, and is laser spot welded from above, but as shown in FIG. 4 (a), the external terminal 5 However, each upright portion may be shortened while maintaining the crank shape, and the terminal connection portion 5a may be connected to the lower side of the terminal 3. Further, as shown in FIG. 4B, a connection between the U-shaped external terminal 5 and the terminal 3 may be used. Alternatively, as shown in FIG. 4C, the L-shaped external terminal 5 and the end face of the terminal 3 may be connected, or may be connected to the side face of the terminal 3 although not shown. Furthermore, as shown in FIG. 4D, when the exterior body is thin, it is also possible to use a flat plate-like external terminal 5.

  Further, the connection form between the balance terminal 7 and the terminal 3 can be various forms similar to those of the external terminal 5 and the terminal 3.

  The connecting plate 8 is a flat plate made of stainless steel (SUS304) having a thickness of 0.15 mm, and is connected across the two single-cell exterior bodies 2 as shown in FIG.

  Moreover, in this embodiment, the attachment position of the connecting plate 8 may be the other surface of the exterior body in addition to the side surface including the terminals 3 in the exterior body as shown in FIG. In particular, as shown in FIG. 6, the connecting plate 8 and the fixed terminal 6 face each other and are connected across a plurality of single cells, so that the single cells are more firmly fixed to each other. Position and parallelism are aligned.

  As for the method of manufacturing the electric double layer capacitor with terminal 10 shown in FIG. 6, the outer body manufacturing step, the step of storing the power generation element and manufacturing the single cell, the step of connecting the single cells, the fixed terminal, the external terminal And each welding process of a balance terminal and the sealing process are provided. Among these, the details of the steps shown in the first embodiment are omitted, and the steps used only in this embodiment will be described.

  The process of connecting the single cells will be described as follows. First, the connecting plate 8 is punched out of a stainless plate with a press or the like and finished to a predetermined size. Subsequently, the plurality of unit cells to be connected are juxtaposed with the side surfaces aligned in the arrangement shown in FIG. Thereafter, the connecting plate 8 is stacked so as to straddle the outer casings 2 of a plurality of single cells, YAG laser light is irradiated from the vertical direction of the connecting plate, and the two adjacent outer casings 2 and the connecting plate 8 are welded. As welding conditions, for example, YAG laser light is applied to four rectangular peripheral portions of the connecting plate 8 at an output of 1.2 kW and an irradiation time of 1.5 msec. By providing at least two to three or more welding points, the connecting plate 8 and the exterior body 2 can be firmly connected.

  Next, the welding process for welding the balance terminal 7 and the terminal 3 fixed to the exterior body 2 will be described below. First, the balance terminal 7 is produced and prepared. Specifically, after a stainless steel plate and a copper plate are superposed, the two plates are pressed and combined. Then, the pressed plate material is punched and bent by a press or the like.

  In addition, copper is easily corroded, and after stamping to cover the second material 72 in order to improve solder wettability during mounting and make mounting on the circuit board easier. Nickel plating and gold plating are performed between any of the processes up to. Thereby, the balance terminal 7 shown in FIG. 7 can be obtained.

  Then, the process of welding the terminal connection part 7a of the balance terminal 7 to the terminal 3 fixed to the exterior body 2 by laser spot welding is performed. About the welding conditions of the external terminal 5 and the balance terminal 7, it is the same as the welding conditions of the external terminal 5 of 1st Embodiment.

(Third embodiment)
Next, an embodiment further different from the above embodiment is shown in FIG. In each of the above embodiments, the exterior body is illustrated in a box shape, but various shapes such as a cylindrical shape such as a cylindrical shape or a button shape, or a cross-sectional shape such as a track shape can be implemented. FIG. 8 shows a shallow button shape in the depth direction.

  FIG. 8A is an external perspective view of the electric double layer capacitor 1 with terminals. FIG. 8B is a cross-sectional view of the terminal-attached electric double layer capacitor 1 taken along line B-B ′ shown in FIG.

  As shown in FIGS. 8A and 8B, the electric double layer capacitor 20 shown in the present embodiment includes a metal button-type exterior body 21 and one terminal fixed thereto by an insulating member 41. 31, an external terminal 53, a fixed terminal 61, a power generation element 18 including a positive electrode, a negative electrode, and a separator, and an electrolyte E. Inside the capacitor, one of the positive and negative electrodes of the power generation element 18 is electrically connected to the terminal 31 via the lead 19. The other pole is electrically connected to the exterior body 21 via the lead 19. Thereby, the exterior body 21 has either positive or negative potential.

  The external terminal 53 has a multilayer structure composed of a first material 54 made of stainless steel and a second material 55 made of copper, and has a crank shape. This external terminal 53 is connected to the terminal 31. Since the second material is partially formed with respect to the first material, the first material 54 and the terminal 31 are welded with the same kind of stainless steel, and not only an electrical connection but also a mechanical connection. Is also firmly connected.

  A flat plate-shaped fixed terminal 61 is electrically connected to the bottom surface of the outer package 21. Either of the positive and negative electrodes can be electrically connected to the circuit board by the fixed terminal 61, and the fixed terminal 61 plays the same role as the external terminal. For this reason, in the present embodiment, the fixed terminal 61 also has a multilayer structure composed of the first material 62 and the second material 63. As a result, not only the internal resistance is reduced, but also copper that can be easily soldered is the second material, so that it can be firmly attached to the circuit board to be mounted.

(Fourth embodiment)
Next, an embodiment in which the connection between the external terminal and the terminal is different is shown in FIG. In the above-described embodiment, as shown in FIG. 1A, the crank-shaped external terminal 5 is connected to the upper portion of the terminal, and the bottom surface portion 5 b is extended in the long side direction of the exterior body 2. As shown in FIG. 9A, the electric double layer capacitor 30 having a structure in which the L-shaped external terminal 56 and the side surface of the terminal 3 are welded may be used.

  In the exterior body manufacturing process described above, when the terminal 3 is fixed by the insulating member 4, the terminal 3 may be inclined and fixed. For the purpose of miniaturization, the length of the terminal 3 is about 4 to 5 mm, the diameter is also selected to be 1 mm or less, and there is a clearance tolerance with a firing jig such as carbon that fixes the position of the terminal 3 during firing. When it is slightly larger, the angle of the terminal 3 is likely to occur although it is a slight angle. In that case, as shown in FIG. 1A, if the shape of the external terminal 5 is a crank shape, the bottom surface height of the external terminal 5 may vary due to the inclination of the terminal 3 with respect to the horizontal plane. There is a risk that the circuit board cannot be mounted horizontally or the connection strength is insufficient.

  Therefore, in such a case, it is preferable that the external terminal has a shape shown in FIG. 9A and the welding position with the terminal 3 is not the top surface of the terminal 3 but the side surface. In this way, it is possible to suppress variations in the height direction that occur from the inclination of the terminal 3 as will be described later. Further, if the external terminal 56 is arranged so as to be welded without exceeding the length of the terminal 3, the length of the electric double layer capacitor 30 in the long side direction is shortened as in the example shown in FIG. As a result, the mounting area can be reduced.

  Here, the connection between the external terminal 56 and the terminal 3 will be described. The two external terminals 56 are placed on the side surface of the terminal 3 so that their bottom surfaces 56b are in contact with one horizontal plane, and then laser spot welding is performed on the side surface of the terminal 3 in consideration of the inclination of the terminal 3. The external terminal 56 is welded by laser irradiation from the lateral direction. At this time, if the inclination of the terminal 3 is recognized in advance by an image processing technique or the like, the height of the welding position can be finely adjusted according to the angle at which the terminal 3 is inclined.

FIG. 9B is a schematic diagram for explaining this situation, and is a cross-sectional view taken along the line BB ′ shown in FIG. The terminal 3 fixed to the insulating member 4 is slightly inclined downward from the horizontal plane (the inclination is θ), but is exaggerated in the drawing. The external terminal 56 is welded to the terminal 3 at two welding points 25a and 25b, and the center of the second welding point 25b is in contact with the first welding point 25a in consideration of the inclination θ of the terminal 3. The distance is set to the lower side by a distance of m × tan (θ) taking into account the horizontal distance m and the inclination θ.
Thus, even when the terminal 3 is inclined, the bottom surface 56b of the external terminal 56 can be set horizontally and can be maintained at a predetermined height.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in each of the above embodiments, an electric double layer capacitor has been described as an example of an electrochemical cell. It can also be applied to other electrochemical cells.

  In each of the above embodiments, the thickness and outer dimensions of the external terminal, balance terminal, fixed terminal, and connecting plate, and the outer dimensions of the terminals and the pitch between the terminals are appropriately set to have optimum dimensions and shapes. It is possible to design. Further, the position and number of terminals to be taken out and the arrangement of single cells in series connection are not limited.

  Further, in each of the embodiments described above, the manufacturing method by deep drawing has been described for the case of the exterior body. However, the case is not limited to the case of pressing or deep drawing with a bottomed shape, and a hollow corner. Alternatively, a cylindrical pipe may be cut into a certain length, and a member to be a bottom plate may be joined by welding.

  Moreover, in each said embodiment, the material of the exterior body and the terminal was set to SUS316L which is austenitic stainless steel from a viewpoint of intensity | strength and corrosion resistance. However, it is not limited to this. For example, SUS329J4L, which is a two-phase stainless steel, may be used, and other stainless steels can be selected. It is also possible to select the material of the exterior body and the material of the terminal separately.

  Furthermore, materials other than stainless steel can be selected as materials for the outer package and the terminal. For example, cold rolled steel plated with a corrosion-resistant material such as nickel can be selected as the exterior body. The terminal can be made of a material such as Kovar.

In each of the above embodiments, copper is used as the second material of the external terminal and the balance terminal, but in addition, the resistivity is lower than that of stainless steel, and it has heat resistance and durability at the reflow temperature. Other metals may be used as long as mounting on a circuit board is easy. For example, the resistivity of nickel at 293K is slightly higher than that of copper, which is 6.99 × 10 ⁻⁸ Ωm, which is about one tenth of that of stainless steel. It is also a good material for mounting on a circuit board.

  In each of the above embodiments, the external terminals and the balance terminals are made of stainless steel and copper clad materials. However, the present invention is not limited to this, and any manufacturing method may be used as long as a multilayer structure such as plating or printing can be formed. .

  In each of the above embodiments, if the external terminal and the balance terminal have a multilayer structure composed of the first material and the second material, in addition to the first material and the second material, further other materials are used. It may be a multilayer structure provided. For example, various structures such as a three-layer structure of stainless steel / copper / stainless steel and a three-layer structure of stainless steel / copper / nickel can improve weldability with a terminal and connection with a circuit board.

  Further, in each of the above embodiments, the fixed terminal is made of a stainless steel flat plate. A partially formed structure may be used. As a result, similar to the plate-like fixed terminal, the circuit board can be mounted in a plurality of regions, and the external body potential can be set to a specific potential or grounded on the circuit board. In that case, it is desirable that the plurality of single cells are firmly connected by a connecting plate or the like so as to withstand a drop impact after mounting.

  Moreover, in each said embodiment, although the terminal, the external terminal, and the balance terminal were welded by laser spot welding, if it is a method which can be connected by local energy irradiation, it will not necessarily be limited to laser spot welding. . For example, if it is the same non-contact type, electron beam welding capable of irradiating a sufficient amount of energy can be employed. Alternatively, connection by resistance welding may be used.

  Moreover, in each said embodiment, it is supposed that it will weld via a connection board about the connection method of exterior bodies at the time of series connection of a cell, but it is not restricted to this, For example, resistance welding, laser welding, electron beam welding, arc The exterior bodies can also be directly fixed using various types of welding such as welding, brazing, adhesion with resin, or the like. In each welding process, the welding conditions are set so as to avoid the heat effect on the power generation element and the electrolyte inside the exterior body. In that case, in order to improve weldability, it is desirable that the exterior bodies are adjacent to each other without a gap. On the other hand, if the exterior bodies are firmly connected via the connecting plate, the exterior bodies do not necessarily have to be in close contact with each other.

DESCRIPTION OF SYMBOLS 1, 10, 20, 30 ... Electric double layer capacitor 2, 21 ... Exterior body 25, 25a, 25b ... Welding point 11 ... Cover member 12 ... Case 3, 31 ... Terminal 4, 41 ... Insulating member 5, 53, 56 ... External terminal 51, 54, 62, 71 ... 1st material 52, 55, 63, 72 ... 2nd material 5a, 56a ... Terminal connection part 5b, 56b ... Bottom surface part 6, 61 ... Fixed terminal 6a ... Upright part 6b ... bottom part 7 ... balance terminal 7a ... terminal connection part 7b ... bottom part 8 ... connecting plate 9 ... sealing plug 16, 18 ... power generation element 17, 19 ... lead E ... electrolyte

Claims (13)

Comprising one or more terminals which are insulated fixed glass hermetic seal on one plane of the metal outer body having two plane faces, power generation elements and an electrolyte are housed inside the outer package, the generator A single cell in which a positive electrode and a negative electrode of the element are electrically connected to the terminal or the exterior body, a fixed terminal connected to the other plane of the exterior body , and the power generation element electrically via the terminal A terminal-attached electrochemical cell comprising connected external terminals,
The fixed terminal includes a bottom surface portion that is a mounting surface with a circuit board,
The external terminal has a bottom portion which is the mounting surface of the terminal connecting portion and the circuit board to be connected to the terminal, and the first material is a metal of the terminal and the same type, resistivity than the first material A terminal-attached electrochemical cell having a multi-layer structure made of a second material having a low level. Comprising one or more terminals which are insulated fixed glass hermetic seal in a single plane of metal outer package is parallelepiped-shaped, power generation elements and an electrolyte are housed inside the outer body, the positive electrode of the power generating element And a plurality of unit cells in which the negative electrode is electrically connected to the terminal or the exterior body, a fixed terminal connected to a surface facing the one plane of the exterior body , and the power generation via the terminal An external terminal and a balance terminal electrically connected to the element, each unit cell is connected so that the one plane and the facing surface are substantially the same plane, and electrically connected via the balance terminal An electrochemical cell with terminals connected in series,
The fixed terminal includes a bottom surface portion that is a mounting surface with a circuit board, and is connected across the plurality of single cells on the facing surface,
Said external terminal and said balanced terminals is provided with a bottom portion is a mounting surface of the terminal connecting portion and the circuit board to be connected to the terminal, and the first material is a metallic of the terminal and the same type, the first material end child with electrochemical cells you being a multilayer structure composed of a low resistivity second material than. The multilayer structure, according to claim, wherein said first material, said second material entirely or partially disposed relative to the first material, the structure der Rukoto constructed from The electrochemical cell with a terminal according to 1 or 2 . Before SL first material is formed of stainless, with a terminal electrochemical cell according to claim 1 or 2, wherein the second material is characterized in that it is formed from copper or an alloy containing copper. Before the cross-section of Kigaibu terminal, a crank shape or U-shaped or having two horizontal portions and one upright section, or flat shape, or according to claim 1 or 2, characterized in that the L-shaped the electrochemical cell with the terminal. Inverted section before Symbol balance terminal, a crank shape or U-shaped or having two horizontal portions and one upright section, or flat plate, or, the U-shaped having a horizontal portion in a U-shape or open end The electrochemical cell with a terminal according to claim 2, wherein the electrochemical cell has a shape. The terminal connecting portion electrochemical cell with terminals according to any one of claims 1 6, characterized in that it comprises a plurality of weld points that by the laser spot welding. Before SL is the surface having the connecting portion between the terminal and the external terminal, an electrochemical cell with terminals according to any one of claims 1 to 7, characterized in that intersects perpendicularly to the substrate surface. Production of exterior body for producing case and lid member constituting metal exterior body including one or more terminals insulated and fixed by glass hermetic seal on one plane of metal exterior body having two opposed planes Preparation and steps, houses a power generation element inside the outer body, a positive electrode and a negative electrode of the power generating element is connected to the terminal or the outer body, a single cell by welding and said cover member and said casing a step of a step of connecting the fixed terminal on the other plane of the exterior body, a step of connecting the outer portions pin, a step of sealing accommodating said exterior body inside the electrolyte, the a method for producing an electrochemical cell with with Ru terminal,
The external terminal includes a terminal connection portion connected to the terminal and a bottom surface portion that is a mounting surface of the circuit board, and has a first material that is the same kind of metal as the terminal, and a resistivity higher than that of the first material. method for producing an electrochemical cell with terminals with you, characterized in that the a low multi-layer structure comprising a second material. And the outer body preparing step of preparing a case and a lid member constituting the metal outer body comprising one or more terminals which are insulated fixed glass hermetic seal in a single plane of metal outer body is a rectangular parallelepiped shape, accommodating the power generation element into the interior of the outer body, a positive electrode and a negative electrode of the power generating element is connected to the terminal or the exterior body, a process of forming a single cell by welding and said cover member and said casing a step plane and the facing surface of said one said unit cell to connect the step of plurality linked so that substantially the same plane, respectively, the fixed terminal on the surface facing the said one plane of said outer body a step of connecting the outer portions pin, Ru comprising a step of connecting the balance terminal and the terminal or the exterior body, a step of sealing accommodating said exterior body inside the electrolyte, the terminal Of attached electrochemical cells A law,
The external terminal and the balance terminal each include a bottom surface portion that is a mounting surface of a terminal connection portion and a circuit board that are connected to the terminal, and a first material that is the same type of metal as the terminal, and the first material method for producing an electrochemical cell with terminals with you being a multilayer structure composed of a low resistivity second material than. Used as formed in the previous SL stainless as the first material, with terminal according to claim 9 or 10, characterized in that used as said formed of copper or an alloy containing copper as the second material Electrochemical cell manufacturing method. Before Kigaibu pin, contact and said pin, by irradiating a laser beam toward the first material of the outer end element, and said pin and the external terminal is welded by laser spot welding The method for producing an electrochemical cell with a terminal according to claim 9 , wherein each welding location is welded at a plurality of welding points. The external terminal, the balance terminal, and the terminal are in contact with each other, and the external terminal, the balance terminal, and the terminal are irradiated by irradiating laser light toward the first material of the external terminal and the balance terminal. The method of manufacturing an electrochemical cell with a terminal according to claim 10, wherein welding is performed by laser spot welding, and welding is performed at a plurality of welding points for each welding point.

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