JP2008028009A - Electric double-layer capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric double-layer capacitor capable of suppressing the departure of a carbon material in a negative electrode layer by preventing the local corrosion of a positive electrode by including a positive electrode layer in the negative electrode layer when viewed from the lamination direction of positive and negative electrodes and holding the negative electrode layer at the outer periphery of the positive electrode layer in a pressing state. <P>SOLUTION: In the electric double-layer capacitor 1A, the positive electrode 6, the negative electrode 9, and an outermost layer negative electrode 9b are laminated via a separator 2 so that the negative electrode layer 11a includes the positive electrode layer 8 when viewed from the lamination direction of the positive electrode 6, the negative electrode 9a, and the outermost layer negative electrode 9b. The electric double-layer capacitor 1A has pressing means 21a, 22A for pressing the positive electrode 6, the negative electrode 9a, the outermost layer negative electrode 9b, and the separator 2 in a lamination direction. The negative electrode layers 11a that are adjacent in the lamination direction of the negative electrode 9a and the outermost layer negative electrode 9b are held in a pressing state at least at one portion of the outer-periphery side of the positive electrode layer 8 by the pressing means 21a, 22A. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric double layer capacitor, and more particularly to an electrode structure capable of preventing the carbon material from being detached from a negative electrode portion not facing the positive electrode.

  For example, a general multilayer electric double layer capacitor is composed of a sheet-like positive electrode and negative electrode made of a carbon material such as activated carbon and having polarizability, and a positive electrode and a negative electrode that are formed of an insulating material and arranged to face each other. A cell portion having a porous separator interposed therebetween and an electrolytic solution impregnated with the separator, and utilizing the capacitance of an electric double layer generated at the interface between the positive electrode or the negative electrode and the electrolytic solution It is. In addition, since the electric double layer capacitor does not involve a chemical reaction in charge and discharge, there is an advantage that a large current can be charged and discharged instantaneously and charge and discharge efficiency is good. Furthermore, the electric double layer capacitor can be charged / discharged 100,000 times or more, and has a merit that the lifetime is 10 years or more and the reliability is high under general use.

  In addition, the electric double layer capacitor is characterized in that the capacitance of the electric double layer capacitor is much larger than that of a general capacitor such as an aluminum capacitor. It is expected to be a key device that helps to save energy and reduce carbon dioxide gas.

  And in order to raise an energy density, the method of laminating | stacking many cell parts in parallel and accommodating in a storage container is taken for the electrical double layer capacitor. At this time, both the front and back surfaces of the positive electrode and the negative electrode are orthogonal to the stacking direction.

  Here, in the positive electrode and the negative electrode facing each other through the separator, when the positive electrode has a portion not facing the negative electrode, when a voltage is applied between the positive electrode and the negative electrode, the positive electrode portion not facing the negative electrode The voltage becomes abnormally high and is corroded locally. It is known that when gas is generated due to corrosion and bubbles of the generated gas adhere to the positive electrode, the charge / discharge characteristics of the electric double layer are deteriorated.

  In view of the above problems, the conventional electric double layer capacitor is formed such that the area of the positive electrode (positive electrode side polarizable electrode) is smaller than the area of the negative electrode (negative electrode side polarizable electrode) and there is no portion of the positive electrode that does not face the negative electrode. The positive electrode and the negative electrode were disposed on the substrate (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 2002-75802

  In a conventional electric double layer capacitor, each of a positive electrode and a negative electrode is bonded to a current collector foil (current collector) made of aluminum or the like with a powdery carbon material (electrode active material) or the like using a binder or the like. It is constituted by.

And if an electric double layer capacitor repeats charging / discharging operation | movement, a carbon material will expand and contract repeatedly. For example, when nano-gate carbon capable of obtaining a large capacitance is used as the carbon material, it is known that the amount of fluctuation in the thickness direction of the positive electrode and the negative electrode in charge / discharge reaches 20 to 30%. Therefore, in order to suppress fluctuations in the thickness of the positive electrode and the negative electrode during charging / discharging, a pressure of about 2 kg / cm ^{2 is} normally applied to the stacked positive and negative electrodes by pressing the cell portions at both ends in the cell stacking direction. It is hung on each side.

  However, since the pressure is not transmitted to the negative electrode portion not facing the positive electrode, the carbon material of the negative electrode portion not facing the positive electrode is detached from the current collector foil after repeated expansion and contraction due to discharging. There is a case. The detached carbon material is mixed into the electrolyte in the separator and reaches the vicinity of the adjacent positive electrode, causing an electrical short circuit. Further, it is known that when a carbon material that is mixed and floated in the electrolyte solution comes into contact with the positive electrode, the positive electrode is easily corroded. Therefore, the problem that gas is generated due to corrosion of the positive electrode is reburned.

  The present invention has been made to solve the above-mentioned problems. When viewed from the lamination direction of the positive electrode and the negative electrode, the positive electrode layer is included in the negative electrode layer to prevent local corrosion of the positive electrode, and the positive electrode layer An object of the present invention is to obtain an electric double layer capacitor capable of suppressing the detachment of the carbon material of the negative electrode layer on the outer peripheral side of the positive electrode layer by holding the negative electrode layer on the outer periphery in a pressurized state.

  In the electric double layer capacitor of the present invention, the positive electrode having the positive electrode layer formed on both surfaces of the positive electrode current collector foil and the negative electrode having the negative electrode layer formed on both surfaces of the negative electrode current collector foil are the outermost layer. A negative electrode layer is formed on one surface of the negative electrode current collector foil, and an outermost negative electrode is formed on the outer surface of the positive electrode located in the outermost layer, with the negative electrode layer interposed between the positive electrode and the positive electrode. The negative electrode layer is disposed so as to face the electrode layer, and the negative electrode layer is formed in an outer shape including the positive electrode layer when viewed from the stacking direction of the positive electrode, the negative electrode, and the outermost negative electrode, and the electrolytic solution is the positive electrode layer, the negative electrode layer, and the separator And a pressurizing unit that pressurizes the positive electrode, the negative electrode, the outermost layer negative electrode and the separator in the stacking direction, and the negative electrode layers adjacent to each other in the stacking direction of the negative electrode and the outermost layer negative electrode are , Positive electrode layer It is held under pressure at least a portion of the outer peripheral side.

  According to the electric double layer capacitor of the present invention, since the negative electrode layer includes the positive electrode layer as viewed from the stacking direction of the positive electrode, the negative electrode, and the outermost negative electrode, local corrosion of the positive electrode is prevented. Further, the portion of the negative electrode layer on the outer periphery of the positive electrode layer is held in a pressurized state by the pressurizing means, and the separation of the carbon material from the negative electrode layer is prevented. It is possible to prevent the occurrence of an electrical short circuit or corrosion of the positive electrode before reaching the vicinity.

The best mode for carrying out the present invention will be described below with reference to the drawings.
Embodiment 1 FIG.
1 is a schematic side sectional view for explaining the configuration of an electric double layer capacitor according to Embodiment 1 of the present invention. FIG. 2 is a side view of the electric double layer capacitor according to Embodiment 1 of the present invention. FIG. 4 is a top view of the electric double layer capacitor according to Embodiment 1 of the present invention, FIG. 4 is a front view showing the structure of the positive electrode inclusion body of the electric double layer capacitor according to Embodiment 1 of the present invention, and FIG. The front view which shows the structure of the 1st negative electrode of the electric double layer capacitor which concerns on Embodiment 1, FIG. 6 is VI-VI arrow sectional drawing of FIG. 3, FIG. 7 is VII-VII arrow sectional drawing of FIG. 8 is a schematic side sectional view showing the state of the adjacent positive electrode inclusion body and the first negative electrode in the electric double layer capacitor according to Embodiment 1 of the present invention, and FIG. 9 is a cross-sectional view taken along arrow IX-IX in FIG. FIG.

  In FIG. 1, in order to make the configuration of the electric double layer capacitor easier to understand, the positive electrode terminal and the negative electrode terminal are deviated from the actual arrangement relationship, or between the positive electrode and the first negative electrode or between the positive electrode and the second negative electrode. Although drawn in a separated state, in reality, the positive electrode terminal and the negative electrode terminal have the same coordinates in the stacking direction, and the positive electrode is included in close contact with the negative electrode as shown in FIG. ing.

  1 and FIGS. 7 to 9 exaggerate the thicknesses of the positive electrode, the first negative electrode, the second negative electrode, and the electrolyte connecting electrode layer. The length of each side of the both sides of the negative electrode and the second negative electrode is much longer than the total thickness of the stacked positive electrode, first negative electrode, and second negative electrode.

First, the main configuration of the electric double layer capacitor 1A will be described.
1 to 9, an electric double layer capacitor 1 </ b> A includes a positive electrode inclusion body 5 including a separator 2 and a sheet-like positive electrode 6 included in the separator 2, a first negative electrode 9 a, and a second negative electrode as an outermost layer negative electrode. It has a negative electrode 9b, an electrolytic solution (not shown), a positive electrode terminal 17, a negative electrode terminal 18, a positive electrode conductor 19, a negative electrode conductor 20, an electrolyte reservoir 21a as a pressurizing means and a strip member, and a storage container 22A as a pressurizing means. is doing.

And the positive electrode inclusion body 5 and the 1st negative electrode 9a are laminated | stacked so that each front and back both surfaces may become mutually parallel. Further, the second negative electrode 9b is disposed on the outer side in the stacking direction of the positive electrode inclusion 5 and the first negative electrode 9a so as to face the outermost positive electrode inclusion 5.
Hereinafter, the stacking direction of the positive electrode inclusion body 5, the first negative electrode 9a, and the second negative electrode 9b is simply referred to as a stacking direction.
The positive electrode 6 is included between the adjacent (opposite) first negative electrodes 9a or between the first negative electrode 9a and the second negative electrode 9b.

The strip-shaped electrolyte reservoir 21a is wound in layers so as to surround both surfaces of the second negative electrode 9b on the outer side in the stacking direction.
Furthermore, the positive electrode 6, the first negative electrode 9a, the second negative electrode 9b, and the separator 2 are impregnated with an electrolytic solution.

  Each positive electrode 6 is connected to a positive electrode terminal 17 and a plurality of positive electrode conductors 19, and each of the first negative electrode 9 a and the second negative electrode 9 b is connected to a negative electrode terminal 18 and a plurality of negative electrode conductors 20. Furthermore, the positive electrode inclusion body 5, the first negative electrode 9a, the second negative electrode 9b, the electrolyte reservoir 21a, and the like are stored in the storage container 22A.

Next, each configuration of the electric double layer capacitor 1A will be described in detail.
As shown in FIG. 4, the positive electrode inclusion body 5 includes a positive electrode 6 and a separator 2 that encloses the positive electrode 6, and the positive electrode 6 is formed on both the front and back surfaces of the positive electrode current collector foil 7 and the positive electrode current collector foil 7. And the positive electrode layer 8.

  The positive electrode current collector foil 7 is made of sheet-like aluminum or the like in which a large number of small holes (not shown) are formed in the thickness direction. The positive electrode current collector foil 7 has a positive electrode current collector foil base portion 7a having a square outer periphery and a positive electrode terminal connection portion 7b extending from a part of one side of the positive electrode current collector foil base portion 7a. Moreover, the positive electrode terminal connection part 7b is rectangular shape, and is extended so that a longitudinal direction may become perpendicular | vertical to one side of the positive electrode current collector foil base part 7a. The size of the positive electrode current collector foil base 7a is 10 cm × 10 cm.

A typical thickness of the positive electrode current collector foil 7 is 20 to 50 μm, but differs depending on a charge / discharge current when charging / discharging the electric double layer capacitor 1A. When the charge / discharge current is large, the positive electrode current collector foil 7 is thick in order to reduce the internal resistance. When the charge / discharge current is small, the charge / discharge time is long. In the case where it is acceptable, the one as thin as possible is used in order to reduce the size of the electric double layer capacitor 1A itself. Here, a positive electrode current collector foil 7 having a thickness of 20 μm is used.
The positive electrode current collector foil 7 may be made of another conductive material such as copper.

  For the positive electrode layer 8, a carbon material such as particulate activated carbon having a diameter of about 10 μm is used. For example, water vapor activated activated carbon, alkaline activated carbon, nanogate carbon, or the like can be used for the positive electrode layer 8. Then, steam-activated activated carbon or the like is bound to the entire area of the front and back surfaces of the positive electrode current collector foil base 7a by a binder (not shown) by a rolling method, a coating method, a molding method, or the like, thereby forming the positive electrode layer 8 Is done. Therefore, the outer shape of the positive electrode layer 8 is the same as that of the positive electrode current collector foil base 7a. For the binder, fluorine resin such as PTFE (polytetrafluoroethylene), SBR (styrene butadiene rubber), acrylic synthetic rubber, or the like is used.

At this time, the amount of the binder is adjusted so as to be a minimum necessary for holding the particulate carbon material so that the entire surface of the carbon material is not covered with the binder.
Thereby, when the electrolytic solution is supplied to the positive electrode layer 8, the electrolytic solution can spread in the positive electrode layer 8.
The typical thickness of the positive electrode layer 8 is 50 μm to 100 μm, but here, a thickness of 50 μm is used.

Separator 2 includes cellulose-based materials such as natural pulp, natural cellulose and solvent-spun cellulose, glass fibers, non-woven fabrics, and fibrillated forms or porous films such as polypropylene, polytetrafluoroethylene (PTFE) and silica-mixed polyethylene. In this case, a polypropylene porous film is used.
The electrolytic solution impregnated in the separator 2 can be transmitted in the thickness direction of the separator 2 through holes (not shown) formed in the thickness direction of the separator 2.

  The separator 2 is formed by folding a rectangular sheet made of polypropylene having a thickness of 25 μm into two at the middle portion in the longitudinal direction so that the surfaces are aligned. Here, the bent portion of the separator 2 is defined as a separator bent portion 3. And the positive electrode 6 is comprised between the two surfaces where the separator 2 opposes so that the thickness direction may correspond to the thickness direction of the separator 2.

At this time, the size of the two opposing surfaces of the separator 2 is larger than the size of the positive electrode current collector foil base 7 a, and the positive electrode layer 8 formed on both surfaces of the positive electrode current collector foil base 7 a It is in a state of being enclosed between two opposing surfaces. And only the front end side of the positive electrode terminal connection portion 7 b protrudes from the anti-bending portion side of the separator 2.
Further, the side of the positive electrode current collector foil base portion 7a on the side opposite to the positive electrode terminal connection portion is arranged along the separator bent portion 3, and both sides perpendicular to the side arranged along the separator bent portion 3 are separator bent portions. Are arranged along both side edges 4 perpendicular to 3.

And between each side 4 of 2 surfaces which the separator 2 opposes is fuse | melted, and the separator junction part 4a is formed. Between the side edges 4 of the separator 2 is closed by the separator joint 4a, and the separator 2 is formed in a bag shape. For the fusion of the separator joining portion 4a, the periphery of each side 4 of the opposing surface of the separator 2 is raised to near the melting point temperature of the material of the separator 2 (polypropylene), and pressure is applied in the thickness direction of the separator 2. It is done by.
Here, the separator 2 has a thickness of 25 μm, and the total thickness of the positive electrode layer 8 formed on both surfaces of the positive electrode current collector foil base 7a and the positive electrode current collector foil base 7a is 120 μm. The total thickness of the portion including the electrode layer 8 is 170 μm.

As shown in FIG. 5, the first negative electrode 9a includes a negative electrode current collector foil 10a and negative electrode layer 11a formed on both the front and back surfaces of the negative electrode current collector foil 10a.
The negative electrode current collector foil 10a is made of sheet-like aluminum or the like in which many small holes (not shown) are formed in the thickness direction, and the negative electrode current collector foil base 25a and the negative electrode current collector foil base 25a have a square outer periphery. Negative electrode terminal connection part 25b extended from a part of one side. The negative electrode current collector foil base 25a has a larger area than the positive electrode current collector foil base 7a. Here, the negative electrode current collector foil base 25a has an outer size of 10.5 cm × 10.5 cm. . Moreover, the negative electrode terminal connection part 25b is rectangular shape, and is extended so that a longitudinal direction may become perpendicular | vertical to one side of the negative electrode current collector foil base 25a.
In addition, you may use other electrically-conductive materials, such as copper, for the material of the negative electrode current collector foil 10a.

Further, the negative electrode layer 11a is formed of the same material as that of the positive electrode layer 8 on both the front and back surfaces of the negative electrode current collector foil base 25a.
The representative thickness of the negative electrode layer 11a is 70 μm to 200 μm, but a voltage larger than that of the positive electrode layer 8 is easily applied to the negative electrode layer 11a, and an overvoltage is prevented from being applied to the first negative electrode 9a. Therefore, the thickness of the negative electrode layer 11a is generally larger than the thickness of the positive electrode layer 8. Here, a negative electrode layer 11a having a thickness of 200 μm is used.

And in each of the negative electrode layer 11a of the 1st negative electrode 9a, on the surface by the side of an anti-negative electrode collector foil, as shown in FIG. 5, the thickness direction of the negative electrode layer 11a is made into the depth direction. Are formed so as to be symmetrical on both sides in the stacking direction of the negative electrode current collector foil 10a.
The first recess portion 15a to the third recess portion 15c are formed by pressing at a predetermined position of the negative electrode layer 11a with high pressure in the thickness direction of the negative electrode layer 11a or by hot pressing. The

  The first recess 15a has a counter current collector of the negative electrode layer 11a while leaving the vicinity of the outer periphery of the negative electrode layer 11a so that a square having four sides parallel to the respective sides of the negative electrode layer 11a has an outer peripheral shape. It is recessed on the surface on the foil side. Here, the outer peripheral shape of the first recess 15 a corresponds to the outer shape of the portion of the separator 2 including the positive electrode layer 8. The depth of the first recess 15a is 80 μm. Therefore, the thickness of the negative electrode layer 11a in the portion where the first recess 15a is formed is 120 μm.

  Furthermore, the 2nd dent part 15b and the 3rd dent part 15c are formed between the one side by which the negative electrode terminal connection part 25b in the negative electrode layer 11a is extended, and the 1st dent part 15a. Yes. The second recess 15b and the third recess 15c are formed by pressing the negative electrode layer 11a so as to compress it by 25 μm and 35 μm, respectively. Therefore, the thickness of the negative electrode layer 11a in the portion where the second recess 15b and the third recess 15c are formed is 175 μm and 165 μm, respectively.

Of the surface on the anti-negative electrode current collector foil side of the negative electrode layer 11a, the portions excluding the bottoms of the first recess portion 15a to the third recess portion 15c are the first negative electrode adhesion surface 16a and the second recess portion 15b. The bottom portions of the third recess 15c are referred to as a second negative electrode contact surface 16b and a third negative electrode contact surface 16c, respectively.
That is, the negative electrode layer 11a is formed by laminating the positive electrode inclusion body 5, the first negative electrode 9a, and the second negative electrode 9b so as to include the positive electrode layer 8 when viewed from the stacking direction. The portion of the negative electrode layer 11a that protrudes to the outer peripheral side of the layer 8 is formed by the first negative electrode adhesion surface 16a to the third negative electrode adhesion surface 16c.

The second negative electrode 9b includes a negative electrode current collector foil 10a, a negative electrode layer 11a formed on one surface of the negative electrode current collector foil 10a, and an electrolyte connecting electrode layer 12a formed on the other surface of the negative electrode current collector foil 10a. It consists of
In addition, a conductive and porous material is used as the material of the electrolyte solution connection electrode layer 12a. Here, the same material as that of the negative electrode layer 11a is used to bind to the other surface of the negative electrode current collector foil base 25a. Is done. However, the electrolyte connection electrode layer 12a is formed to a uniform thickness of 200 μm and does not have an uneven shape.
Here, in the first negative electrode 9a and the second negative electrode 9b, the side on the side opposite to the negative electrode terminal connecting portion is set as a base side 13a, and two sides perpendicular to the base side 13a are set as side sides 14a.
The electrolyte reservoir 21a is formed in a long band shape having the same width as one side of the negative electrode current collector foil base 25a, and the same material as that of the separator 2 is used.

The electrolytic solution is an ionic liquid or the like in which an electrolyte is dissolved in a solvent.
Examples of the electrolyte include a combination of a cation and an anion. , 3-trialkylimidazolium and the like, a salt of which the anion is BF ₄ ⁻ , PF ₆ ⁻ , ClO ₄ ⁻ , or CF ₃ SO ₃ ^— , 1-ethyl-3-methylimidazolium (EMI), 1, 2-dimethyl-3-AlCl propyl imidazolium (DMPI) ₄ ^- or BF ₄ ^- and salts, such as are used. In addition, as a solvent, propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, dimethoxymethane, diethoxyethane, γ-butyllactone, acetonitrile, a mixed solvent of two or more of these selected from propionitrile, and the like are used. ing.

  The storage container 22A is composed of a first half container 23a and a second half container 23b that are bowl-shaped and formed in the same shape, and the first half container 23a and the second half container 23b cooperate with each other. In other words, the opening edges of the first half container 23a and the second half container 23b are combined to contain the positive electrode inclusion body 5, the first negative electrode 9a, the second negative electrode 9b, and the electrolyte reservoir 21a. Is.

The first half-container 23a and the second half-container 23b are formed of an aluminum laminate film, plastic, various metals, or the like. Also, as shown in FIG. 3, the notches 24a and 24b are formed in the first half-container 23a. Cutouts 24c and 24d are formed on one side of the opening side edge of the second half-container 23b, and the first half-container 23a and the second half-container 23b are combined. In this case, the notch 24a and the notch 24c, and the notch 24b and the notch 24d cooperate to form the positive electrode terminal hole 26a and the negative electrode terminal hole 26b communicating with the inside and outside of the storage container 22A. The positive terminal 17 and the negative terminal 18 are respectively inserted into the positive terminal hole 26 a and the negative terminal hole 26 b, and electrical exchange between the inside and outside of the storage container 22 </ b> A is performed via the positive terminal 17 and the negative terminal 18.

Next, a structure in which the first negative electrode adhesion surface 16a to the third negative electrode adhesion surface 16c of the negative electrode layer 11a protruding from the outer periphery of the positive electrode layer 8 as viewed from the stacking direction are pressurized will be described in detail.
The positive electrode inclusion body 5 and the first negative electrode 9a configured as described above are alternately laminated so that the front and back surfaces of the positive electrode inclusion body 5 and the front and back surfaces of the first negative electrode 9a are parallel to each other.

  At this time, the positive electrode inclusion body 5 is laminated in five layers so as to come to the outermost layer, and the first negative electrode 9a is laminated in four layers. Furthermore, the second negative electrode 9 b is disposed on the outer side of the outermost positive electrode inclusion body 5 in the stacking direction so as to face the positive electrode inclusion body 5. At this time, the electrolyte connection electrode layer 12a is disposed so as to be directed outward in the stacking direction. As a result, the positive electrode 6, the first negative electrode 9 a, and the second negative electrode 9 b are alternately stacked with the separators 2 interposed therebetween so that the front and back surfaces are parallel to each other.

  The positive electrode layer 8 is fitted in the first recess 15a of the negative electrode layer 11a of the first negative electrode 9a or the second negative electrode 9b. Therefore, the positive electrode layer 8 is included between the negative electrode layers 11a of the adjacent first negative electrodes 9a or between the first negative electrode 9a and the negative electrode layer 11a of the second negative electrode 9b. That is, the surface of the positive electrode layer 8 on the side of the anti-positive electrode current collector foil faces the bottom surface of the first recess 15a.

  At this time, the positive electrode inclusion body 5, the first negative electrode 9a, and the second negative electrode 9b are arranged such that the positive electrode terminal connection portion 7b and the negative electrode terminal connection portion 25b protrude in the same direction. Moreover, the anti-bending part side of both surfaces of the positive electrode terminal connection part 7b and the opposing separator 2 protrudes from between the adjacent negative electrode layers 11a. Further, the tip of the positive electrode terminal connection portion 7 b further protrudes from the tip of the separator 2 on the side opposite to the bent portion. At this time, the second recessed portion 15b and the third recessed portion 15c formed in each of the negative electrode layer 11a are formed on the portion of the separator 2 that extends from the upper end of the positive electrode layer 8 on the side opposite to the bent portion. Of these, the third recess 15c corresponds to the portion of the separator 2 that interposes the positive electrode terminal connection portion 7b.

  In the adjacent negative electrode layer 11a, the first negative electrode contact surface 16a directly faces without the separator 2 interposed therebetween, and the second negative electrode contact surface 16b and the third negative electrode contact surface 16c face the separator 2. ing.

As described above, the depth of the first recess 15a of the negative electrode layer 11a is 80 μm, the thickness of the positive electrode layer 8 is 50 μm, the thickness of the positive current collector foil 7 is 20 μm, The separator 2 has a thickness of 25 μm.
Therefore, the total thickness of the portion of the positive electrode terminal connection portion 7b that is in close contact with the separator 2 and the separator 2 is 70 μm, and the total thickness of the portion of the separator 2 that is in direct contact is 50 μm. It is.

  Accordingly, when the first recess 15a is fitted from both sides of the positive electrode inclusion body 5 and the bottom of the first recess 15a is in close contact with the separator 2 including the positive electrode layer 8, the stacking direction If the pressure is not applied, the distance between the first negative electrode contact surface 16b of the negative electrode layer 11a facing each other is 10 μm, and the separator is opposed to each of the second negative electrode contact surface 16b and the third negative electrode contact surface 16c. The distance from 2 is 5 μm. However, the pressure is applied to each of the positive electrode 6, the first negative electrode 9a, the second negative electrode 9b, and the separator 2 by the electrolyte reservoir 21a and the storage container 22A from both outside in the stacking direction to the inside. . Accordingly, a surface pressure is applied between the surface of the positive electrode layer 8 on the side of the anti-positive current collector foil and the bottom surface of the first recess 15a, and further, the positive electrode 6, the first negative electrode 9a, and the second negative electrode 9b. And the separator 2 is compressed.

  That is, as the positive electrode 6, the first negative electrode 9 a, the second negative electrode 9 b, and the separator 2 are compressed, the first negative electrode close contact surface 16 a is opposed to the opposing first negative electrode close contact surface 16 a. The surface 16b and the third negative electrode adhesion surface 16c are pressed against the separator 2 facing each other, and the first negative electrode adhesion surface 16a to the third negative electrode adhesion surface 16c of the adjacent first negative electrode 9a or second negative electrode 9b. Are in close contact and held in a pressurized state. That is, the portion of the negative electrode layer 11a that protrudes from the outer peripheral side of the positive electrode layer 8 when viewed from the stacking direction is also maintained in a pressurized state.

  Here, a plurality of electrolyte reservoirs 21a are provided so as to cover the outer surfaces of the electrolyte solution connecting electrode layers 12a disposed at both ends in the stacking direction and the end surfaces of the negative electrode layer 11a on both sides 14a side. The positive electrode inclusion body 5, the first negative electrode 9a, and the second negative electrode 9b are pressed in the stacking direction. Further, the winding start portion of the electrolyte reservoir 21a is on the outer surface in the stacking direction of the electrolyte connecting electrode layer 12a, and the winding end portion of the electrolyte reservoir 21a is adhesive on the wound electrolyte reservoir 21a itself. May be fixed.

  Further, when the first half-container 23a and the second half-container 23b enclose the positive electrode inclusion body 5, the first negative electrode 9a, the second negative electrode 9b, and the electrolyte reservoir 21a with the respective opening edges aligned. Further, the inner walls of the first half container 23a and the second half container 23b are in close contact with the outer peripheral surface of the electrolyte reservoir 21a in a pressed state, so that the positive electrode 6, the first negative electrode 9a, the second negative electrode 9b, and the separator 2, pressure is applied in the stacking direction. And between the opening edge part of the 1st half container 23a and the 2nd half container 23b which were match | combined, it is fixed with an adhesive agent etc., and 22 A of storage containers are formed.

As a result, the first negative electrode contact surface 16a of the adjacent negative electrode layer 11a, the second negative electrode contact surface 16b, the third negative electrode contact surface 16c, and the separator 2 are in close contact with each other and the pressurized state is maintained. Retained. Further, the surface of the electrolyte solution connecting electrode layer 12a on the side opposite to the negative electrode current collector foil and the electrolyte reservoir 21a are brought into close contact with each other and the pressurized state is maintained. Note that when the applied pressure is 2 kg / cm ² or more, the activated carbon of the negative electrode current collector foil 10a is more effectively prevented from being detached.

  Further, the positive electrode terminal hole 26a and the negative electrode terminal hole 26b formed by the cutout 24a and the cutout 24c and the cutout 24b and the cutout 24d are extended from the positive electrode terminal connection portion 7b and the negative electrode terminal connection portion 25b. Are arranged. The positive electrode terminal 17 and the negative electrode terminal 18 are inserted into the positive electrode terminal hole 26a and the negative electrode terminal hole 26b so as to protrude into and out of the storage container 22A.

The positive electrode terminal 17 and the positive electrode terminal connection portion 7b, and the negative electrode terminal 18 and the negative electrode terminal connection portion 25b are connected in advance by the positive electrode conductor 19 and the negative electrode conductor 20.
The material of the positive electrode terminal 17 and the negative electrode terminal 18 is not particularly limited as long as it is conductive, but aluminum, copper, or the like is used. At this time, if the material of the storage container 22A is conductive, the positive electrode terminal 17, the negative electrode terminal 18 and the storage container 22A are brought into contact so that the positive electrode terminal 17 and the negative electrode terminal 18 are not short-circuited via the storage container 22A. An insulating material (not shown) is interposed in the portion.

Here, the activated carbon of the positive electrode layer 8, the negative electrode layer 11a, and the electrolyte connecting electrode layer 12a expands when the electric double layer capacitor 1A is charged and contracts during discharge.
Therefore, the electrolytic solution overflows when the activated carbon expands during charging and there is no gap between the activated carbons, and it is necessary to recapture the overflowed electrolytic solution during discharge.
Here, as described above, the separator 2, the positive electrode current collector foil 7, and the negative electrode current collector foil 10 a are formed with holes in the thickness direction, and the electrolyte solution includes the positive electrode 6, the first negative electrode 9 a, and the first negative electrode current collector foil 10 a. It is possible to flow between the two negative electrodes 9b.

When a shortage of the electrolytic solution occurs in the positive electrode layer 8 and the negative electrode layer 11a, the electrolytic solution in the electrolytic solution reservoir 21a is supplied to the electrolytic solution communication electrode layer 12a in close contact with the electrolytic solution reservoir 21a, and then the second electrode It flows to the negative electrode current collector foil 10a and the negative electrode layer 11a of 9b. Furthermore, the electrolyte solution of the negative electrode layer 11a of the second negative electrode 9b flows to the adjacent positive electrode 6 with the separator 2 interposed therebetween. Then, the electrolytic solution impregnated in the positive electrode 6 adjacent to the second negative electrode 9b further flows to the first negative electrode 9a adjacent to the positive electrode 6 inward in the stacking direction. The electrolytic solution sequentially flows toward the inner side of the first negative electrode 9a and the positive electrode 6 in the stacking direction while compensating for the shortage of the electrolytic solution in the positive electrode 6 and the first negative electrode 9a. On the contrary, when the electrolytic solution oozes out from the positive electrode layer 8 or the negative electrode layer 11a, the electrolytic solution is absorbed into the electrolytic solution reservoir 21a.
Accordingly, when the electrolyte reservoir 21a repeatedly expands due to charging or contracts due to discharge, the electrolyte reservoir 21a absorbs the overflowing electrolyte and compensates for the insufficient electrolyte.

  In the first embodiment, a positive electrode 6 is included in a bag-like separator 2. The first negative electrode 9 a and the negative electrode layer 11 a of the second negative electrode 9 b are formed larger than the positive electrode layer 8 of the positive electrode 6. Further, first to third recesses 15a to 15c corresponding to the outer shape of the positive electrode 6 are provided in the negative electrode layer 11a. And the part of the positive electrode layer 8 of the positive electrode inclusion body 5 is included between the 1st recessed parts 15a of the adjacent negative electrode layer 11a. Moreover, the 2nd dent part 15b and the 3rd dent part 15c of the negative electrode layer 11a are arrange | positioned in the part of the separator 2 and the positive electrode terminal connection part 7b extended from the one side of the positive electrode current collection foil base 7a. . Therefore, each of the first negative electrode adhesion surface 16a to the third negative electrode adhesion surface 16c of the adjacent negative electrode layer 11a is arranged to face each other directly or via the separator 2 or the like.

  And it has so that it has the inner wall of the shape which can press the electrolyte solution reservoir 21a and the electrolyte solution reservoir 21a wound so that the space | interval of the surface of the electrolyte solution connection electrode layer 12a arrange | positioned at the both ends of the lamination direction may be covered. The positive container 5, the first negative electrode 9 a, and the second negative electrode 9 b are pressed in the stacking direction by the storage container 22 </ b> A manufactured in the above. Therefore, not only between the portion of the negative electrode layer 11a facing the positive electrode layer 8 and the separator 2, but also between the first negative electrode adhesion surface 16a of the adjacent negative electrode layer 11a without passing through the negative electrode current collector foil 10a, Furthermore, the separator 2 facing each of the second negative electrode contact surface 16b and the third negative electrode contact surface 16c is in close contact and held in a pressurized state. Further, the surface on the side of the anti-negative electrode current collector foil of the electrolyte solution communication electrode layer 12a is also brought into close contact with the electrolyte solution reservoir 21a and held in a pressurized state. In addition to this, a large pressure is applied by the storage container 22A. .

  Therefore, according to the first embodiment, since the entire areas of both the front and back surfaces of the negative electrode layer 11a and the electrolyte solution connection electrode layer 12a are pressurized, it is possible to prevent the carbon material of the activated carbon from being separated. Therefore, it is possible to prevent the detached carbon material from reaching the positive electrode 6 to cause an electrical short circuit or the like, or to corrode the positive electrode. Furthermore, since the positive electrode layer 8 is fitted into the first recess 15a, the positive electrode 6 can be reliably disposed at a predetermined position of the negative electrode layer 11a without causing a positional shift or the like.

Further, since the first negative electrode contact surfaces 16a of the adjacent negative electrode layers 11a are directly in close contact with each other and the adjacent negative electrode layers 11a are electrically connected, the internal resistance of the electric double layer capacitor 1A can be lowered. .
Further, since the electrolyte reservoir 21a is formed of a porous material, the electrolyte can be impregnated, and when the electric double layer capacitor 1A repeatedly expands and contracts due to discharge, the positive electrode inclusion 5 and the first The electrolyte overflowing from the negative electrode 9a and the second negative electrode 9b can be absorbed, and the insufficient electrolyte can be compensated.
Further, the provision of the conductive and porous electrolyte connection electrode layer 12a does not hinder the exchange of the electrolyte with the electrolyte reservoir 21a, and further reduces the internal resistance of the electric double layer capacitor 1A. be able to.

  In addition, by using the positive electrode inclusion body 5 included in the separator 2 formed in a bag shape, it is not necessary to align the positive electrode 6 and the separator 2 when the electric double layer capacitor 1A is assembled. Even if a part of the carbon material of the positive electrode layer 8 is detached, the separator bent portion 3 and the side 4 of the separator 2 are closed, so that the carbon material is directed from the positive electrode inclusion body 5 to the outside. This makes it difficult to float and short-circuiting due to the carbon material reaching the negative electrode is suppressed.

Embodiment 2. FIG.
10 is a side sectional view of the electric double layer capacitor according to the second embodiment of the present invention, and FIG. 11 is a sectional view taken along the line XI-XI in FIG.
10 and 11, the third negative electrode 9c is composed of a negative electrode current collector foil 10a and negative electrode electrode layers 11b formed on both the front and back surfaces of the negative electrode current collector foil 10a. The fourth negative electrode 9d as the outermost layer negative electrode includes a negative electrode layer 11b formed on one surface of the negative electrode current collector foil 10a, and an electrolyte connecting electrode layer 12a formed on the other surface of the negative electrode current collector foil 10a. It consists of The negative electrode layer 11b is made of the same material as the negative electrode layer 11a, has the same vertical and horizontal dimensions as the negative electrode layer 11a, and has a uniform thickness of 200 μm.

  And the positive electrode inclusion body 5 and the 3rd negative electrode 9c are laminated | stacked so that each front and back both surfaces may become mutually parallel. Furthermore, the fourth negative electrode 9d is disposed so as to face the outermost positive electrode inclusion body 5 on the outer side in the stacking direction.

At this time, the positive electrode inclusion body 5, the third negative electrode 9c, and the fourth negative electrode 9d are stacked so that the negative electrode layer 11b includes the positive electrode layer 8 when viewed from the stacking direction.
Further, the portion of the negative electrode layer 11b that protrudes from the positive electrode layer 8 when viewed from the stacking direction is defined as a fourth negative electrode adhesion surface 16d.

  The first contact member 27 as a negative electrode contact member in the form of a rectangular sheet having a long side having the same length as one side of the positive electrode layer 8 is an anti-bending portion of the separator 2 of the positive electrode layer 8. Arranged on the side.

  The first contact member 27 is arranged such that the end surface on one side of the long side is aligned with the end surface of the positive electrode layer 8 on the side opposite to the bent portion. The first contact member 27 is formed using the same material as the separator 2 and has the same thickness (50 μm) as the positive electrode layer 8, but the portion overlapping the positive electrode terminal connection portion 7 b is preliminarily formed by a high pressure press. The positive terminal connection portion 7b is compressed by a thickness of 20 μm. Further, the other side of the long side of the first contact member 27 protrudes further from the end surface of one side of the negative electrode layer 11b extending side of the negative electrode terminal connection portion 25b.

Further, in the adjacent negative electrode layer 11b, a second contact member 28 as a negative electrode contact member is disposed in a space between the faces directly facing each other without the separator 2 interposed therebetween. The thickness of the second contact member 28 is formed to be the same as the thickness (170 μm) of the portion having the positive electrode layer 8 of the positive electrode inclusion body 5. Each of the second contact members 28 is formed in a U-shape, and from one end side of the first contact member 27, the side 4 on one side of the separator 2, the bent portion 3, and the separator 2. It extends along the other side 4 so as to reach the other end of the first contact member 27.
The fourth negative electrode adhesion surface 16d of the adjacent negative electrode layer 11b is held in a pressurized state by the first adhesion member 27 via a separator or by the second adhesion member 28.

The second contact member 28 is made of the same material as the negative electrode layer 11a (or the positive electrode layer 8) or a conductive material such as a metal foil such as an aluminum foil or a copper foil. Here, what formed the steam activated carbon by 170 micrometers in thickness with the binder is used.
Other configurations are the same as those in the first embodiment.

  In the electric double layer capacitor 1B configured as described above, the first close contact member 27 and the second close contact member 28 interpose the negative electrode layer 11b of the adjacent third negative electrode 9c. Or a space between the third negative electrode 9c and the negative electrode layer 11b of the fourth negative electrode 9d is eliminated.

  In this state, when the electrolyte reservoir 21a is wound and the storage container 22A is further assembled, the fourth negative electrode close contact surface 16d and the second close contact member 28 and the fourth negative electrode close contact surface 16d The portion of the separator 2 that encloses the first contact member 27 is brought into close contact with each other and is held in a pressurized state. Furthermore, the adjacent negative electrode layer 11b is brought into close contact via the conductive second contact member 28, and the adjacent negative electrode layer 11b conducts, so that the internal resistance of the electric double layer capacitor 2B is reduced. .

  Therefore, according to the second embodiment, the same effect as in the first embodiment can be obtained.

Embodiment 3 FIG.
FIG. 12 is a side sectional view of an electric double layer capacitor according to Embodiment 3 of the present invention, and FIG. 13 is a sectional view taken along arrow XIII-XIII in FIG.

  12 and 13, the positive electrode inclusion body 5 and the fifth negative electrode 9 e are laminated so that both front and back surfaces are parallel to each other. Furthermore, the sixth negative electrode 9f as the outermost layer negative electrode is arranged on the outer side in the stacking direction so as to face the positive electrode inclusion body 5 of the outermost layer.

  The fifth negative electrode 9e and the sixth negative electrode 9f are formed larger than the outer shapes of the third negative electrode 9c and the fourth negative electrode 9d. The signs of the negative electrode 9e and the sixth negative electrode 9f (negative current collector foil, negative electrode layer, and electrolyte connection electrode layer) are the same as the signs of the third negative electrode 9c and the fourth negative electrode 9d. Something is used.

Of the fifth negative electrode 9e and the sixth negative electrode 9f, a portion protruding from the outer peripheral side of the positive electrode layer 8 when viewed from the stacking direction forms a bent portion 30.
Four sides of each of the fifth negative electrode 9e and the sixth negative electrode 9f are bent toward the fifth negative electrode 9f disposed at the center of the stack among the plurality of fifth negative electrodes 9f stacked.
Further, the bending angle of the sixth negative electrode located outward in the stacking direction is the largest, and the bending angle is smaller toward the fifth negative electrode 9e disposed at the inner center in the stacking direction.
The electrolyte reservoir 21 b is also wound around the bent portion 30.

Furthermore, the inner wall of the storage container 22A is in close contact with the electrolyte reservoir 21b in a state of pressing the electrolyte reservoir 21b, and not only the stacking direction of the positive electrode inclusion body 5, the fifth negative electrode 9e, and the sixth negative electrode 9f, The fifth negative electrode 9e and the sixth negative electrode 9f are formed in a shape that allows pressure to be applied also in the thickness direction of the bent portion 30.
Other configurations are the same as those of the second embodiment.

In the electric double layer capacitor 1C configured as described above, not only the portion of the negative electrode layer 11a facing the positive electrode layer 8 but also the adjacent bent portion 30 is added by the electrolyte reservoir 21b and the storage container 22A. Held in pressure. That is, the entire area of the front and back surfaces of the negative electrode layer 11a is maintained in a pressurized state.
Therefore, according to the third embodiment, the same effect as in the first embodiment can be obtained.

Embodiment 4 FIG.
FIG. 14 is a side sectional view of an electric double layer capacitor according to Embodiment 4 of the present invention.

  In FIG. 14, the seventh negative electrode 9 g as the outermost layer negative electrode is disposed further outward in the stacking direction of the positive electrode inclusion body 5 stacked in the outermost layer.

The seventh negative electrode 9g is composed of a negative electrode layer 11c formed on one surface of the negative electrode current collector foil 10b and an electrolyte connecting electrode layer 12b formed on the other surface of the negative electrode current collector foil 10b.
The base side 13b side of the seventh negative electrode 9g extends from the base side 13a of the first negative electrode 9a. A portion of the seventh negative electrode 9 g that extends from the base side 13 a of the first negative electrode 9 a is referred to as an outermost negative electrode bent portion 31.

  Each of the outermost negative electrode bent portions 31 of the seventh negative electrode 9g is bent at 90 degrees toward the inner side in the stacking direction. At this time, the respective end surfaces of the outermost negative electrode bent portion 31 are arranged to face each other and are in close contact with each other. Furthermore, the end surface on the base side 13a side of the negative electrode layer 11a of the first negative electrode 9a is covered in close contact with the surface on the anti-negative electrode current collector foil side of the outermost negative electrode bent portion 31 of the seventh negative electrode 9g. .

The inner walls of the third half container 23c and the fourth half container 23d of the storage container 22B press the electrolyte connection electrode layer 12b of the outermost negative electrode bent portion 31 of the electrolyte reservoir 21a in the thickness direction. It is formed to be in close contact.
Other configurations are the same as those in the first embodiment.

  The electric double layer capacitor 1D configured as described above is opposed to the positive electrode layer 8 of the negative electrode layers 11a and 11c of the first negative electrode 9a and the seventh negative electrode 9g by the electrolyte reservoir 21a and the storage container 22B. In addition to the portions to be applied, the entire areas of the front and back surfaces of the negative electrode layers 11a and 11c and the electrolyte solution connection electrode layer 12b are maintained in a pressurized state. Further, the respective end faces of the negative electrode layer 11a on the base side 13a side are connected by the negative electrode layer 11c of the seventh negative electrode 9g, and the current collecting effect on the base side 13a side is further enhanced.

  Therefore, according to the fourth embodiment, in addition to the effect similar to the effect of the first embodiment, the effect that the internal resistance of the electric double layer capacitor 1D can be further reduced can be obtained.

Embodiment 5. FIG.
15 is a cross-sectional view of an electric double layer capacitor according to Embodiment 5 of the present invention.
In addition, a cross-sectional view is a figure equivalent to sectional drawing when an electric double layer capacitor is cut | disconnected in the surface perpendicular | vertical to the paper surface in FIG. 1 and parallel to a lamination direction.

  In FIG. 15, the eighth negative electrode 9 h as the outermost layer negative electrode is disposed further outward in the stacking direction of the positive electrode inclusion body 5 stacked in the outermost layer.

The eighth negative electrode 9h is composed of a negative electrode layer 11d formed on one surface of the negative electrode current collector foil 10c and an electrolyte connecting electrode layer 12c formed on the other surface of the negative electrode current collector foil 10c.
And the both sides 14b side of the 8th negative electrode 9h is extended from the end surface of the both sides 14a of the 1st negative electrode 9a.

Each side 14b is bent at 90 degrees toward the negative electrode layer 11a arranged at the center of the stack. Here, in the eighth negative electrode 9h, a portion extending from the side 14a is defined as the outermost surface negative electrode bent portion 32. At this time, the respective front end surfaces of the outermost surface negative electrode bent portion 32 are arranged so as to be in close contact with each other. Further, the surface of the negative electrode layer 11d on the side of the anti-negative electrode current collector foil is in close contact with the end surface of the first negative electrode 9a on the side 14a side at the outermost surface negative electrode bent portion 32.
Other configurations are the same as those in the first embodiment.

  The thus configured electric double layer capacitor 1E is opposed to the positive electrode layer 8 among the negative electrode layers 11a and 11d of the first negative electrode 9a and the eighth negative electrode 9h by the electrolyte reservoir 21a and the storage container 22A. Not only the portion, but the entire area of both the front and back surfaces of the negative electrode layers 11a and 11d is maintained in a pressurized state. Further, the respective end surfaces of the negative electrode layer 11a on the side 14a side are in close contact with and connected to the negative electrode layer 11d of the eighth negative electrode 9h, thereby further enhancing the current collecting effect on the side 14a.

  Therefore, according to the fifth embodiment, in addition to the same effect as that of the first embodiment, an effect that the internal resistance of the electric double layer capacitor 1E can be further reduced can be obtained.

Embodiment 6 FIG.
FIG. 16 is a cross-sectional view of an electric double layer capacitor according to Embodiment 6 of the present invention.

  In FIG. 16, the ninth negative electrode 9i as the outermost layer negative electrode is composed of a rectangular negative electrode current collector foil 10d and a negative electrode layer 11e formed on one surface of the negative electrode current collector foil 10d.

  Then, the ninth negative electrode 9i faces the negative electrode layer 11e inward so as to cover each of the outermost surface of the positive electrode inclusion body 5 in the stacking direction and the end surfaces of the negative electrode layer 11a on both sides 14a side. It is wound only once. Further, a negative electrode winding member 33 as a rectangular sheet-like band member is wound so as to cover the outer periphery of the negative electrode current collector foil 10d. The negative electrode winding member 33 may be conductive, but aluminum is used here.

Further, the negative electrode winding member 33 is tensioned in the length direction so that the surface pressure is applied to both the front and back surfaces of the positive electrode inclusion body 5, the negative electrode layer 11a of the first negative electrode 9a, and the second negative electrode layer 11e. Winding while working, both ends of the negative electrode winding member 33 are fixed by a caulking portion 33a wound in a cigar shape.
Although other configurations are formed in the same manner as in the first embodiment, the electrolyte reservoir 21a is not wound.

The electric double layer capacitor 1F configured as described above includes the positive electrode layer 8 and the negative electrode layers 11a and 11e of the first negative electrode 9a and the ninth negative electrode 9i by the negative electrode winding member 33 and the storage container 22A. Not only the facing portions but also the entire areas of the front and back surfaces of the negative electrode layer 11a and the negative electrode layer 11e are maintained in a pressurized state.
Further, the respective end surfaces of the negative electrode layer 11a on the side 14a side are connected by the negative electrode layer 11d of the ninth negative electrode 9i, and the current collecting effect on the side 14a side is further enhanced.

  Therefore, according to the sixth embodiment, the internal resistance can be reduced in addition to the effect of the first embodiment. Moreover, since the negative electrode winding member 33 covers the side edge 14a side of the negative electrode layer 11a, the electrolyte solution can be prevented from leaking from the side edge 14a side of the negative electrode layer 11a.

  Although both ends of the negative electrode winding member 33 are fixed by the caulking portion 33a, the fixing of both ends of the negative electrode winding member 33 is not limited to that by the caulking portion 33a, and both ends of the negative electrode winding member 33 are fixed. May be bent together, or both ends of the negative electrode winding member 33 may be combined and fixed with an adhesive or the like.

Embodiment 7 FIG.
FIG. 17 is a side sectional view of an electric double layer capacitor according to Embodiment 7 of the present invention.

  In FIG. 17, the tenth negative electrode 9j as the outermost layer negative electrode includes a rectangular negative electrode current collector foil 10e, a negative electrode layer 11f formed on one surface of the negative electrode current collector foil 10e, and the other surface of the negative electrode current collector foil 10e. And an electrolyte solution connecting electrode layer 12d formed on the substrate.

The tenth negative electrode 9j is formed in a U shape with the tenth negative electrode layer 11f as an inner wall, and the positive electrode inclusion body 5 and the first negative electrode 9a stacked on the inner wall of the tenth negative electrode 9j. Is covered. At this time, the end face on the base 13a side of the first negative electrode 9a is in close contact with the bottom of the U-shape, and the U-shaped side piece is in close contact with the outer surface in the stacking direction of the positive electrode inclusion body 5 as the outermost layer. ing.
Other configurations are the same as those in the first embodiment.

The thus configured electric double layer capacitor 1G is opposed to the positive electrode layer 8 to the negative electrode layers 11a and 11f of the first negative electrode 9a and the tenth negative electrode 9j by the electrolyte reservoir 21a and the storage container 22B. Not only the part to perform, but the whole area of both the front and back surfaces of the negative electrode layer 11a and the negative electrode layer 11e is maintained in a pressurized state.
In addition, since the bottom of the negative electrode layer 11f of the tenth negative electrode 9j is in contact with the end surface on the base 13a side of the first negative electrode 9a, current collection on the base 13a side of the first negative electrode 9a is performed. The effect is further increased.

  Therefore, according to the seventh embodiment, in addition to the effects of the first embodiment, the internal resistance can be further reduced.

Embodiment 8 FIG.
FIG. 18 is a schematic side sectional view of an electric double layer capacitor according to Embodiment 8 of the present invention, and FIG. 19 is a cross sectional view of the electric double layer capacitor according to Embodiment 8 of the present invention.

In FIG. 18 and FIG. 19, the extending direction of the negative electrode terminal connecting portion 25b is opposite to the extending direction of the positive electrode terminal connecting portion 7b. Furthermore, the positive electrode terminal 17 and the negative electrode terminal 18 are taken out from the opposite surfaces of the storage container 22C.
Other configurations are the same as those in the first embodiment.

The electric double layer capacitor 1H configured in this manner also takes out the positive electrode terminal 17 and the negative electrode terminal 18 from the opposite surfaces of the storage container 22C, and also on the first negative electrode adhesion surface 16a to the third negative electrode adhesion surface 16c. As in the first embodiment, a surface pressure is applied.
Therefore, according to the eighth embodiment, in addition to the effects of the first embodiment, the degree of freedom in the mechanism design of the electric double layer capacitor 1H can be increased.

In each embodiment, the number of stacked positive electrode inclusions 5 is five and the number of first negative electrodes 9a is four. However, the stack of positive electrode inclusions 5 and first negative electrodes 9a is described. The number is not limited, and the number of stacked layers of the positive electrode inclusion body 5 and the first negative electrode 9a may be appropriately determined according to the specification environment of the electric double layer capacitor.
Further, the outer shape and size of the positive electrode current collector foil 7 and the positive electrode layer 8, the negative electrode current collector foils 10a to 10e, and the negative electrode layers 11a to 11f may be appropriately determined according to the specification environment of the electric double layer capacitor. .

  Further, the negative electrode layers adjacent to each other in the stacking direction have been described as being held in a pressurized state over the entire outer peripheral portion of the positive electrode layer viewed from the stacking direction. When always used in a constant state, the portion of the negative electrode layer on the outer peripheral side of the positive electrode layer that is disposed below the positive electrode in the direction of gravity is a carbon material even if the carbon material is detached from each negative electrode layer. However, it is not always necessary to maintain the pressurized state because it floats in the electrolyte and hardly reaches the positive electrode side.

  Further, the parallel multilayer type electric double layer capacitors 1A to 1H have been described as examples, but the present invention can also be applied to a wound type electric double layer capacitor.

It is a side cross-sectional schematic diagram for demonstrating the structure of the electric double layer capacitor which concerns on Embodiment 1 of this invention. 1 is a side view of an electric double layer capacitor according to Embodiment 1 of the present invention. It is a top view of the electric double layer capacitor according to the first embodiment of the present invention. It is a front view which shows the structure of the positive electrode inclusion body of the electric double layer capacitor which concerns on Embodiment 1 of this invention. It is a front view which shows the structure of the 1st negative electrode of the electric double layer capacitor which concerns on Embodiment 1 of this invention. It is VI-VI arrow sectional drawing of FIG. It is a VII-VII arrow sectional view of Drawing 3. In the electric double layer capacitor according to the first embodiment of the present invention, it is a schematic side sectional view showing the state of adjacent positive electrode inclusions and first negative electrodes. It is IX-IX arrow sectional drawing of FIG. It is a sectional side view of the electric double layer capacitor which concerns on Embodiment 2 of this invention. It is XI-XI arrow sectional drawing of FIG. It is a sectional side view of the electric double layer capacitor which concerns on Embodiment 3 of this invention. It is XIII-XIII arrow sectional drawing of FIG. It is a sectional side view of the electric double layer capacitor which concerns on Embodiment 4 of this invention. It is a cross-sectional view of the electric double layer capacitor according to the fifth embodiment of the present invention. It is a cross-sectional view of the electric double layer capacitor according to the sixth embodiment of the present invention. It is a sectional side view of the electric double layer capacitor based on Embodiment 7 of this invention. It is a side cross-sectional schematic diagram of the electric double layer capacitor which concerns on Embodiment 8 of this invention. It is a cross-sectional view of the electric double layer capacitor according to the eighth embodiment of the present invention.

Explanation of symbols

  1A to 1H Electric double layer capacitor, 2 separator, 6 positive electrode, 7 positive electrode current collector foil, 8 positive electrode layer, 9a first negative electrode (negative electrode), 9b second negative electrode (outermost layer negative electrode), 9c third negative electrode (Negative electrode), 9e 5th negative electrode (negative electrode), 9d 4th negative electrode (outermost layer negative electrode), 9f-9j 6th-10th negative electrode (outermost layer negative electrode), 10a-10d Negative electrode current collector foil, 11a- 11f Negative electrode layer, 12a-12d Electrolyte connection electrode layer, 21a, 21b Electrolyte reservoir (band-like member, pressurizing means), 22A, 22B Storage container (pressurizing means), 15a-15c First recess-first 3 indentations (indentations), 27 first adhesion member (negative electrode adhesion member), 28 second adhesion member (negative electrode adhesion member), 30 bent portion, 33 negative electrode winding member (band member) .

Claims (9)

A positive electrode in which the positive electrode layer is formed on both sides of the positive electrode current collector foil and a negative electrode in which the negative electrode layer is formed on both surfaces of the negative electrode current collector foil are laminated via a separator so that the positive electrode is the outermost layer,
The outermost negative electrode formed by forming the negative electrode layer on one surface of the negative electrode current collector foil is opposed to the positive electrode layer with the negative electrode layer interposed on the outer side of the positive electrode located in the outermost layer. Arranged,
The negative electrode layer is formed in an outer shape that includes the positive electrode layer as viewed from the stacking direction of the positive electrode, the negative electrode, and the outermost negative electrode,
In the electric double layer capacitor in which the electrolytic solution is impregnated in the positive electrode layer, the negative electrode layer and the separator,
A pressurizing means for pressurizing the positive electrode, the negative electrode, the outermost negative electrode, and the separator in the stacking direction;
The negative electrode layers adjacent to each other in the stacking direction of the negative electrode and the outermost negative electrode are held in a pressurized state by at least a part of the outer peripheral side of the positive electrode layer by the pressurizing means. Electric double layer capacitor.   A recess is formed on the surface of the negative electrode layer facing the positive electrode, the positive electrode layer is included between the recesses of the adjacent negative electrode layer, and the adjacent negative electrode layers are 2. The electric double layer capacitor according to claim 1, wherein the electric double layer capacitor is held in a pressurized state directly on the outer peripheral side of the positive electrode layer or through the separator.   A bent portion is formed by bending the outer peripheral side of the positive electrode layer of the negative electrode and the outermost negative electrode to the negative electrode side disposed at the center of the stack, and the adjacent bent portions are directly or the separators 3. The electric double layer capacitor according to claim 1, wherein the electric double layer capacitor is held in a pressurized state.   The electric double layer capacitor according to claim 1, wherein the negative electrode adhesion member is interposed between the outer peripheral sides of the positive electrode layers of the adjacent negative electrode layers.   5. The electric double layer capacitor according to claim 4, wherein at least a part of the negative electrode adhesion member has conductivity.   The electric double layer capacitor according to any one of claims 1 to 5, wherein the separator is formed in a bag shape containing the positive electrode.   The said pressurizing means is a strip | belt-shaped member wound so that the said positive electrode, the said negative electrode, the said outermost layer negative electrode, and the said separator may be enclosed, The any one of Claim 1 thru | or 6 characterized by the above-mentioned. The electric double layer capacitor as described.   8. The electric double layer capacitor according to claim 7, wherein the belt-shaped member is an electrolyte reservoir in which a porous material is impregnated with an electrolyte.   9. The electric double layer capacitor according to claim 8, wherein a porous and conductive electrolyte connecting electrode layer is formed on the other surface of the negative electrode current collector foil of the outermost negative electrode.

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