JP2012248556A - Electrochemical device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrochemical device that reduces a manufacturing cost, does not cause self-discharge failure, has a small internal resistance and has excellent volume energy density, and to provide a method for manufacturing the same.SOLUTION: The electrochemical device comprises: an electrode body 15 that is formed by alternately stacking a positive electrode 22 and a negative electrode 32 through a separator 14, the positive electrode 22 and the negative electrode 32 having an active material electrode layer formed at least one principal surface of a collector made of a metal foil; a lithium supply sheet 12 which makes the negative electrode 32 store a lithium ion. The electrochemical device is manufactured by sealing the electrode body 15 and the lithium supply sheet 12 in a packaging material together with an electrolyte. The lithium supply sheet 12 is constituted by forming a lithium supply source 12a on one principal surface of a lithium collector 12b made of a metal foil. The lithium supply source 12a is arranged at least one outer surface side of an outermost layer of the electrode body 15 through the lithium collector 12b.

Description

  The present invention relates to an electrochemical device such as a lithium ion capacitor and a lithium ion secondary battery, and a method for producing the same.

  Conventionally, as an electrochemical device having a power supply function capable of charging and discharging, there are an electric double layer capacitor, a lithium ion secondary battery, and the like. In recent years, a hybrid type capacitor (hereinafter referred to as “hybrid capacitor”) such as a lithium ion capacitor in which a positive electrode of an electric double layer capacitor and a negative electrode of a lithium ion secondary battery are combined is also known.

Electrochemical devices such as those mentioned above are used as energy sources for driving motors such as electric vehicles, or as key devices for energy regeneration systems, as well as for CO ₂ emissions such as uninterruptible power supplies, wind power generation, and solar power generation. Application to various new uses that contribute to volume reduction is being studied.

  In recent years, electrochemical devices are required to increase the amount of energy that can be stored (higher energy) and lower resistance in application to energy sources and energy regeneration applications.

  Electric double layer capacitors are classified into an aqueous electrolyte type and a non-aqueous electrolyte type depending on the type of electrolyte used. The withstand voltage of a single electric double layer capacitor is about 1.2 V in the case of an aqueous electrolyte type, and about 2.7 V in the case of a non-aqueous electrolyte type. In order to increase the energy capacity that can be stored in the electric double layer capacitor, it is important to further increase the withstand voltage, but there is a limit in configuration.

  On the other hand, a lithium ion secondary battery is composed of a positive electrode mainly composed of a lithium-containing transition metal oxide, a negative electrode mainly composed of a carbon material capable of inserting and extracting lithium ions, and an organic electrolyte containing a lithium salt. Has been. When the lithium ion secondary battery is charged, lithium ions are desorbed from the positive electrode and occluded in the carbon material of the negative electrode. Conversely, when discharged, lithium ions are desorbed from the negative electrode and occluded in the metal oxide of the positive electrode. Lithium ion secondary batteries have the property of higher voltage and higher capacity than electric double layer capacitors.

  The lithium ion capacitor uses activated carbon for the positive electrode and a carbon material that can occlude and desorb lithium ions for the negative electrode. Since the negative electrode is accompanied by occlusion and desorption reactions of lithium ions during charging and discharging, the potential difference between the electrodes generated inside the capacitor increases. Therefore, compared with a conventional electric double layer capacitor using activated carbon for the positive electrode and the negative electrode, the withstand voltage can be further increased and the energy can be increased.

By the way, the lithium ion secondary battery put into practical use uses a carbon material such as graphite as a negative electrode and a lithium-containing metal oxide such as LiCoO ₂ or LiMn ₂ O ₄ as a positive electrode as described above. This lithium ion secondary battery is a rocking chair type structure in which lithium ions are supplied from the lithium-containing metal oxide of the positive electrode to the negative electrode by charging after the battery is assembled, and further, the lithium ion of the negative electrode is returned to the positive electrode in the discharge. It is.

  In order to realize high energy of the rocking chair type lithium ion secondary battery, there is a technique of pre-occlusion in which lithium derived from the positive electrode and negative electrode is previously contained in the battery, and lithium ions are occluded from the lithium to the positive electrode or negative electrode Has been done. This pre-occlusion is also applied to a lithium ion capacitor, realizing high energy. Specifically, metallic lithium is bonded to the negative electrode, inserted into the battery cell together with the positive electrode and the separator, an electrolytic solution is injected, and lithium ions are previously occluded in the negative electrode by electrical contact. However, this method has a problem that metal lithium foil needs to be bonded to each negative electrode, resulting in complicated manufacture. In addition, since there is a limit to the thickness of the metal lithium foil, there is a problem that the negative electrode on which the metal lithium foil is bonded becomes thick, resulting in design limitations.

  For example, Patent Document 1 proposes a countermeasure for the above-described problem. Patent Document 1 discloses an organic electrolyte battery including a positive electrode, a negative electrode, and an aprotic organic solvent solution of a lithium salt as an electrolytic solution, wherein the positive electrode current collector and the negative electrode current collector have holes that penetrate the front and back surfaces, respectively. The negative electrode active material is capable of reversibly supporting lithium, the negative electrode-derived lithium is supported by electrochemical contact with the negative electrode or lithium disposed opposite to the positive electrode, and the opposing area of lithium is the negative electrode An organic electrolyte battery that is 40% or less of the area is described.

  As in Patent Document 1, by using a punching metal or an expanded metal having holes that penetrate the front and back surfaces of the positive electrode current collector and the negative electrode current collector, lithium ions are stacked on the through holes of a plurality of current collectors. Moving in the direction, lithium from the negative electrode is inserted. Therefore, there is no need to bond the metal lithium foil to the negative electrode, and the design is less restricted by the thickness of the negative electrode on which the metal lithium foil is bonded.

  Patent Document 2 also includes a laminated electrode body in which positive and negative electrodes are alternately laminated with a separator interposed therebetween, a nonaqueous electrolytic solution in which lithium salt is dissolved, and a laminated electrode body together with the nonaqueous electrolytic solution. A lithium ion energy storage device has been proposed in which a metal container is installed on the side surface of a laminated electrode body.

  In Patent Document 2, by arranging metallic lithium along the side surface of the laminated electrode body, lithium ions reach the respective negative electrodes simultaneously and occluded from the laminated end face of the laminated electrode body. Therefore, there is no need to bond metal lithium to the negative electrode, and the design is less restricted by the thickness of the negative electrode bonded with metal lithium.

International Publication No. 98/33227 JP 2007-305521 A

  However, when a current collector having a through-hole is used for the positive electrode current collector and the negative electrode current collector as in Patent Document 1, the current collection performance of the current collector is impaired, and the internal resistance increases. . In addition, there is a problem that the contact area between the current collector and the active material decreases, the contact resistance increases, and the internal resistance increases.

  Moreover, when using expanded metal and punching metal as a current collector having a through hole, the material cost of these current collectors is about 10 times that of a foil-shaped current collector without a through hole. There is a problem that costs increase. When the through-hole of the current collector is molded with a mold, the opening diameter is large, and the following problems may occur when an active material is applied to one or both sides of the current collector. That is, when the active material is applied to one side of the current collector or both sides of the current collector, the electrode slurry that forms the active material layer may fall off the surface of the current collector. It is conceivable that the electrode that has fallen out may cause conduction between the positive electrode and the negative electrode, and a phenomenon in which a significant voltage drop occurs when left untreated, that is, self-discharge failure increases. Also, when performing double-sided simultaneous coating with a multi-coater, etc., it is difficult to adjust the coating thickness, resulting in large thickness variations, and the current collector has poor strength due to the through-holes in the current collector. Therefore, the manufacturing process of the active material layer becomes complicated and the manufacturing cost increases.

  When a foil-like current collector without through-holes is used for the positive electrode current collector and the negative electrode current collector, there is a problem that even when lithium ions are preoccluded from the lithium supply source to the negative electrode, it is difficult to occlude evenly. . For example, it is conceivable that excessive lithium ions are occluded in the negative electrode disposed closest to the lithium supply source, and if the lithium ions are not occluded evenly, the potential of the excessively occluded negative electrode is remarkably lowered and metal lithium is deposited. In addition, a self-discharge failure may occur.

  On the other hand, in the case of a configuration in which metallic lithium is arranged on the side surface of a laminated electrode body composed of a positive electrode, a negative electrode, and a separator as in Patent Document 2, a space for arranging metallic lithium on the side surface is required. Since the space for arranging the metal lithium does not contribute to the capacity of the lithium ion storage element, there is a problem in that the volume energy density is lowered.

  The present invention has been made in order to solve the above-described problems, and its purpose is to reduce the manufacturing cost, to have no self-discharge failure, to have a low internal resistance, and to have a good volume energy density, and its electrochemical device. It is to provide a manufacturing method.

  The present invention provides a second collector on the outer surface side of at least one of the outermost layers of an electrode body in which positive and negative electrodes each having an active material layer formed on a first current collector are alternately laminated via separators. A lithium supply source is provided via an electric body. The negative electrode is preliminarily occluded in which lithium ions are inserted from a lithium supply source. At this time, with the configuration of the present invention, lithium ions diffuse radially from the lithium supply source, and the diffused lithium ions move from the side surface direction of the electrode body and are occluded in each negative electrode. Therefore, even when no through hole is provided in the current collector, each negative electrode can be preliminarily occluded.

  That is, according to the present invention, an electrode body in which positive electrodes and negative electrodes each having an active material layer formed on at least one main surface of a first current collector made of metal foil are alternately stacked via separators. And an electrochemical device comprising a lithium supply plate that occludes lithium ions in the negative electrode, wherein the electrode body and the lithium supply plate are sealed together with an electrolyte with an exterior material, the lithium supply plate, A lithium supply source is formed on at least a part of one main surface of the second current collector made of a metal foil, and the lithium supply source is on at least one outer surface side of the outermost layer of the electrode body, An electrochemical device is obtained, which is arranged via the second current collector.

  Further, according to the present invention, there is obtained the above electrochemical device characterized in that the lithium supply source is formed on the entire surface of one main surface of the second current collector.

  Further, according to the present invention, the above-described electrochemical device is obtained, wherein the lithium supply source is formed at an end portion of the second current collector.

  Further, according to the present invention, there is obtained the above electrochemical device characterized in that the lithium supply source is metallic lithium or a lithium-containing transition metal oxide.

  According to the present invention, the lithium-containing transition metal oxide is selected from any one of lithium manganate, lithium cobaltate, lithium nickelate, lithium nickel cobaltate, nickel cobalt lithium manganate, and lithium iron phosphate. The above-described electrochemical device is obtained.

  In addition, according to the present invention, an electrode body is produced by alternately laminating a positive electrode and a negative electrode having an active material layer formed on at least one main surface of a first current collector made of metal foil via a separator. A method for producing an electrochemical device, wherein the negative electrode is provided with a lithium supply plate that occludes lithium ions, and the electrode body and the lithium supply plate are sealed together with an electrolyte with an exterior material. Is formed by forming a lithium supply source on at least a part of one main surface of the second current collector made of metal foil, and the lithium supply source is formed on at least one outer surface side of the outermost layer of the electrode body. In addition, a method for producing an electrochemical device is provided, wherein the electrochemical device is disposed via the second current collector.

  Further, according to the present invention, the method for producing an electrochemical device described above is characterized in that after the lithium ion is occluded in the negative electrode, the lithium supply plate is taken out of the exterior material.

  Further, according to the present invention, there is obtained the above-described electrochemical device manufacturing method, wherein the lithium supply source is formed on the entire surface of one main surface of the second current collector.

  According to the present invention, there is provided the method for producing an electrochemical device described above, wherein the lithium supply source is formed at an end of the second current collector.

  Moreover, according to this invention, the said lithium supply source is metallic lithium or a lithium containing transition metal oxide, The manufacturing method of said electrochemical device characterized by the above-mentioned is obtained.

  According to the invention, the lithium-containing transition metal oxide is selected from lithium manganate, lithium cobaltate, lithium nickelate, lithium nickel cobaltate, nickel cobalt lithium manganate, and lithium iron phosphate. The method for producing an electrochemical device described above is obtained.

  In the electrochemical device of the present invention, when lithium ions are previously occluded in the negative electrode, lithium ions diffuse radially from a lithium supply source disposed on the outer surface side of the electrode body via the second current collector. The electrode body moves from the side surface in the stacking direction to the negative electrode. Therefore, lithium ion can be evenly occluded in the negative electrode, self-discharge failure can be improved, and a capacitance equivalent to the conventional one can be secured. Moreover, since the lithium supply plate is arranged in parallel with the negative electrode or the like constituting the electrode body, it is possible to reduce the size and increase the energy density. Further, by using a metal foil having no through-hole as the current collector, the current collecting property and the contact resistance are improved, so that the resistance can be reduced and the self-discharge failure can be improved. Furthermore, since an expensive current collector such as an expanded metal or a punching metal having a through hole is not used, the material cost can be reduced and the manufacturing can be simplified, and the manufacturing cost can be reduced.

  Therefore, according to the present invention, it is possible to provide an electrochemical device with reduced manufacturing cost, no self-discharge failure, low internal resistance, and good volume energy density, and a method for manufacturing the same.

The figure which shows the electrode body and lithium supply board of the lithium ion capacitor which concern on this invention. 1A is a perspective view, and FIG. 1B is a schematic cross-sectional view in which the thickness direction of the AA line is enlarged. The top view which shows other embodiment of the lithium supply board which concerns on this invention. The figure which shows the lithium ion capacitor which concerns on this invention. 3A is a plan view, FIG. 3B is a front view, and FIG. 3C is a cross-sectional view taken along the line BB. The figure which shows the structure of the electrode body which concerns on this invention. 4A is a plan view of the negative electrode plate, FIG. 4B is a plan view of the separator, and FIG. 4C is a plan view of the positive electrode plate. The perspective view which shows the electrode body which concerns on this invention. The perspective view which shows the electrode body and external terminal which concern on this invention. The top view which shows the electrode which concerns on the comparative example 1. FIG. The top view which shows the electrode which concerns on the comparative example 2. FIG. The top view which shows the electrode and lithium supply source which concern on the comparative example 3.

  Embodiments of the electrochemical device of the present invention will be described below with reference to the drawings.

  FIG. 1 is a view showing an electrode body and a lithium supply plate of a lithium ion capacitor according to the present invention, FIG. 1 (a) is a perspective view, and FIG. 1 (b) is a schematic view in which the thickness direction of the AA line cross section is enlarged. FIG. In this embodiment mode, a case of a lithium ion capacitor as an electrochemical device is shown. Even in the case of a lithium ion secondary battery, the configuration and arrangement of the lithium supply plate used, the arrangement of the positive electrode active material layer and the negative electrode active material layer, the configuration provided with the external terminal plate, the electrolytic solution, and the exterior film There is no particular difference in the configuration of the sheet, and the present embodiment can be applied.

  As shown in FIG. 1, in the present invention, the lithium supply plate 12 is disposed on at least one outer surface side of the outermost layer of the electrode body 15 in which the positive electrodes 22 and the negative electrodes 32 are alternately stacked via the separators 14. It has a configuration. In the lithium supply plate 12, a lithium supply source 12a is formed on one surface of a lithium current collector 12b that is a second current collector, and the surface on which the lithium supply source 12a is formed is connected to the electrode body 15 via the lithium current collector 12b. It is the structure located in the outer surface side.

  In the lithium supply plate 12, metal lithium as a lithium supply source 12a is bonded and fixed to a lithium current collector 12b made of a metal foil such as copper. The lithium supply source 12a may be formed on the entire surface of one side of the lithium current collector 12b, but is preferably formed partially. Furthermore, the lithium ion can be smoothly occluded in the negative electrode by being formed at the end of the lithium current collector 12b. FIG. 2 is a plan view showing another embodiment of the lithium supply plate according to the present invention. As described above, in the lithium supply plate 12, the formation position of the lithium supply source 12a is preferably the end of the lithium current collector 12b, but the formation location is not particularly limited. As shown in FIG. 1, the lithium supply source 12a may be formed at both ends of the short side of the lithium current collector 12b so as to be parallel to the long side, or as shown in FIG. It may be formed in a U shape at both end portions and one end portion of the long side, or may be formed at end portions of all sides.

  The lithium supply plate 12 is provided with an extending portion for attaching an external terminal, and the lithium supply plate external terminal 11 is joined by ultrasonic welding. The joining method is not limited to ultrasonic welding, but may be resistance welding, laser welding, or the like.

  3A and 3B are diagrams showing a lithium ion capacitor according to the present invention, in which FIG. 3A is a plan view, FIG. 3B is a front view, and FIG. 3C is a cross-sectional view taken along line BB. The lithium ion capacitor 100 includes an electrode body 15 and a lithium supply plate 12 and is immersed in an electrolytic solution. The lithium ion capacitor 100 is covered with an exterior material 16. The positive electrode external terminal 21 and the negative electrode external terminal 31 protrude from one short side, and the lithium supply plate external terminal 11 protrudes from the other short side. . As shown in FIGS. 3A and 3B, the positive electrode external terminal 21, the negative electrode external terminal 31, and the lithium supply plate external terminal 11 are sandwiched by the exterior material 16 and project outward.

  The outer packaging material 16 sandwiches the electrode body 15 and the lithium supply plate 12 from the upper side and the lower side, adheres the upper and lower outer packaging materials 16 to each other at the peripheral edge, seals the contents containing the electrolyte, and leaks the leakage. Is configured to prevent. In addition, in the joint portion where the positive electrode external terminal 21, the negative electrode external terminal 31, and the lithium supply plate external terminal 11 are led out, the periphery of each external terminal is covered and sealed. Therefore, the lithium ion capacitor 100 is completely sealed by adhesion between the exterior materials 16 and covering around the joint portion between the positive external terminal 21 and the negative external terminal 31 by the external material 16. A laminate film in which a metal foil and a polyolefin film are bonded can be used for the exterior material 16. Further, a thermoplastic resin is formed inside the exterior material 16, and polyethylene, polypropylene, acid-modified propylene, an ethylene-methacrylic acid copolymer, or the like can be used as the thermoplastic resin.

  In the lithium ion capacitor 100 according to the embodiment of the present invention, lithium ions are preoccluded in the negative electrode by an electrochemical method. As an electrochemical method, the lithium supply plate external terminal 11 and the negative electrode external terminal 31 are electrically connected, and a lithium ion is occluded by utilizing a potential difference between the lithium supply source and the negative electrode in the electrolytic solution. Various methods according to the prior art, such as a method of occluding lithium ions while being controlled by an external device such as a discharge device, can be applied. Further, a method in which lithium ions are adsorbed on the positive electrode and the lithium ions are occluded in the negative electrode of the counter electrode is also possible. Although it is desirable to take out the lithium supply plate 12 after occlusion of lithium ions into the negative electrode, it is set in advance so that it is consumed using a lithium supply source that matches the occlusion amount, and the external terminals 11 of the lithium supply plate external terminals 11 A portion protruding from the material 16 to the outside may be cut.

  4A and 4B are diagrams showing the configuration of the electrode body according to the present invention. FIG. 4A is a plan view of the negative electrode, FIG. 4B is a plan view of the separator, and FIG. 4C is a plan view of the positive electrode. FIG. 4A includes a negative electrode active material layer 32a and a negative electrode current collector 32b. Of these, the negative electrode active material layer 32a is generally a negative electrode current collector made of a metal foil such as copper or a copper alloy. It is formed on one side or both sides of the electric body 32b. The negative electrode active material layer 32a is an electrode mixture layer containing a large amount of an active material mainly composed of a carbon material, and often contains a binder and a conductive agent. The negative electrode current collector 32b is provided with an extending portion for attaching an external terminal, and is generally formed integrally with the negative electrode current collector 32b, but some thin metal body is welded to the negative electrode current collector 32b. Or it may be fixed by a method such as crimping.

  The separator 14 shown in FIG. 4 (b) is an insulating thin plate, and generally has a slightly larger area than the formation area of the positive electrode active material layer 22a and the negative electrode active material layer 32a, and is a material that easily penetrates the electrolyte. is required.

  The positive electrode 22 shown in FIG. 4C is composed of a positive electrode active material layer 22a and a positive electrode current collector 22b. Of these, the positive electrode active material layer 22a is generally a positive electrode current collector made of a metal foil such as aluminum or aluminum alloy. It is formed on one side or both sides of the electric body 22b. The positive electrode active material layer 22a is an electrode mixture layer containing a large amount of an active material mainly composed of a carbon material, and often contains a binder and a conductive agent. The positive electrode current collector 22b is provided with an extension for attaching an external terminal, and is generally integrally formed with the positive electrode current collector 22b, but some thin metal body is welded to the positive electrode current collector 22b. Or it may be fixed by a method such as crimping.

  The electrode body is formed by laminating the separator shown in FIG. 4 (b), the negative electrode shown in FIG. 4 (a), the separator shown in FIG. 4 (b), and the positive electrode shown in FIG. 4 (c) from the top. is there. There must be a separator between the adhesive layer inside the upper exterior material and the uppermost negative electrode, between the positive electrode and the negative electrode, and between the lowermost negative electrode and the adhesive layer inside the lower exterior material. One by one is inserted. That is, the configuration of the electrode body in the exterior material is separator / negative electrode / separator / positive electrode / separator /./ separator / positive electrode / separator / negative electrode / separator. The dimensions and number of the positive electrode and the negative electrode are not necessarily the same.

  FIG. 5 is a perspective view showing an electrode body according to the present invention. As described above, the electrode body 15 is configured by laminating the positive electrode 22 and the negative electrode 32 via the separator. From one short side of the positive electrode 22 and the negative electrode 32, an extending portion for attaching an external terminal is drawn out.

  FIG. 6 is a perspective view showing an electrode body and external terminals according to the present invention. The positive electrode external terminal 21 and the negative electrode external terminal 31 are attached to the electrode body 15. The extended portions of the plurality of positive electrodes 22 and the positive external terminals 21 extending from one short side of the electrode body 15, and the extended portions and negative electrode external terminals of the plurality of negative electrodes 32 that are also extended. 31 is joined by ultrasonic welding. The joining method is not limited to ultrasonic welding, but may be resistance welding, laser welding, or the like.

  Here, an example of a method for manufacturing a lithium ion capacitor as a multilayer hybrid capacitor in the embodiment of the present invention will be described below.

(Positive electrode)
The positive electrode has a current collector made of a metal foil made of aluminum foil, stainless steel foil, or the like, and an active material layer mainly composed of a carbon material, a binder, and a conductive agent mixed into a sheet-like positive electrode active material layer. It has been made. The carbon raw material used as the active material includes plant materials such as wood, sawdust, coconut husk and pulp waste liquid, coal, heavy petroleum oil, coal-based and petroleum-based pitch obtained by pyrolyzing them, and petroleum coke. Various materials such as fossil fuel materials such as carbon aerogel and tar pitch, and synthetic polymer materials such as phenol resin, polyvinyl chloride resin, and polyvinylidene chloride are used. These carbon material after carbonization, and activating the gas activation method or chemical activation method, the specific surface area to obtain a carbon-based active material of 700m ² / g~3000m ² / g. The specific surface area of the active material is particularly preferred if the 1000m ² / g~2000m ² / g. As the binder, fluorine-containing resins such as polytetrafluoroethylene, polyvinylidene fluoride and fluoroolefin copolymer cross-linked polymers, rubber binders such as styrene-butadiene rubber, thermoplastic resins such as polypropylene and polyethylene, etc. are used. In addition, it is preferable to produce the binder including about 3 mass% to 20 mass% of the binder in the whole positive electrode active material layer. Among these substances, polytetrafluoroethylene is particularly preferable as the binder from the viewpoint of heat resistance, chemical resistance, and strength of the sheet-like polarizable electrode layer to be produced. In addition, as the conductive agent, a material selected from carbon black such as acetylene black and ketjen black, natural graphite, and thermally expanded graphite carbon fiber is added in an amount of about 5% by mass to 30% by mass of the entire positive electrode active material layer. It is preferable.

  Next, an example of a method for producing a positive electrode will be described. In the following example, a phenol resin is used as a carbon raw material to be an active material, polytetrafluoroethylene is selected as a binder material, and ketjen black is selected as a conductive agent. First, activated carbon powder obtained by carbonizing and activating a phenol resin, a binder made of polytetrafluoroethylene, and a ketjen black are kneaded, and then rolled to form a sheet-like active material layer. The positive electrode active material layer thus obtained is bonded to a roughened positive electrode current collector made of aluminum or stainless steel using a conductive carbon paste. Furthermore, it integrates by heating-drying and makes this a positive electrode. At this time, it is preferable to previously form one extension portion on the positive electrode current collector, and to provide a portion to which the external terminal plate is attached so as not to form the positive electrode active material layer.

  The positive electrode may be manufactured by a method in which the positive electrode active material layer and the positive electrode current collector are overlapped with each other and are bonded to each other instead of the above method. Moreover, this positive electrode active material layer may be adhered to one surface of the positive electrode current collector, or may be adhered to both surfaces. Further, by mixing and dispersing the above active material and conductive agent in a solution in which a binder such as methylcellulose or polyvinylidene fluoride is dissolved in a solvent, a slurry is formed, and this slurry is applied to one or both sides of the positive electrode current collector. A positive electrode active material layer may be formed.

(Negative electrode)
The negative electrode has a negative electrode active material layer formed by mixing a metal foil current collector made of copper foil, nickel foil, stainless steel foil, or the like with an active material mainly composed of a carbon material, a binder, and a conductive agent into a sheet shape. , Integrated. As the active material containing a carbon material as a main component, a carbon-based material such as graphite or amorphous carbon that can occlude and desorb lithium ions can be used. As the conductive agent, carbon black such as acetylene black and ketjen black, natural graphite, and thermally expanded graphite carbon fiber are preferable, and it is preferable to add about 5 to 30% by weight of the whole negative electrode active material layer. The binder includes fluorine-containing resins such as polytetrafluoroethylene, polyvinylidene fluoride and fluoroolefin copolymer crosslinked polymers, rubber binders such as polybutadiene rubber and styrene-butadiene rubber, and thermoplastic resins such as polypropylene and polyethylene. In particular, polyvinylidene fluoride is preferable from the viewpoints of heat resistance, chemical resistance, and sheet strength. It is preferable that the negative electrode active material layer is made to contain about 3 to 20% by weight of the binder.

  Next, an example of a method for producing a negative electrode will be described. In the following example, a non-graphitizable carbon material is used as a carbon raw material as an active material, polytetrafluoroethylene is selected as a binder material, and ketjen black is selected as a conductive agent. First, a non-graphitizable carbon material powder, a binder composed of the above polytetrafluoroethylene, and ketjen black are kneaded and then rolled to form a sheet-like active material electrode layer. The negative electrode active material layer thus obtained is bonded to a copper, nickel or stainless steel negative electrode current collector using a conductive carbon paste. Furthermore, it integrates by heating-drying and makes this a negative electrode. At this time, it is preferable to previously form one extension portion on the negative electrode current collector, and to provide a portion to which the external terminal plate is attached so as not to form the negative electrode active material layer.

  The negative electrode may be produced by a method in which the negative electrode active material layer and the negative electrode current collector are superposed and bonded to each other instead of the above method. Moreover, this negative electrode active material layer may be adhered to one surface of the negative electrode current collector, or may be adhered to both surfaces. Further, by mixing and dispersing the above active material and conductive agent in a solution in which a binder such as methylcellulose or polyvinylidene fluoride is dissolved in a solvent, a slurry is obtained, and this slurry is applied to one or both sides of the negative electrode current collector. A negative electrode active material layer may be produced.

(Separator)
The separator provided between the positive electrode and the negative electrode or between the exterior material and the negative electrode is preferably a material having a small thickness and high electronic insulation and ion permeability. Although the constituent material of a separator is not specifically limited, For example, the nonwoven fabrics, such as polyethylene and a polypropylene, or the papermaking of a viscose rayon or a natural cellulose is used suitably. The constituent material of the separator is preferably selected according to the type of electrochemical device to be produced.

(Lithium supply plate)
Next, an example of a method for producing a lithium supply plate will be described. As the lithium source, metallic lithium or lithium-containing transition metal oxide is used. Examples of the lithium-containing transition metal oxide include lithium manganate (LiMnO ₂ , LiMn ₂ O ₄ ), lithium cobaltate (LiCoO ₂ ), lithium nickelate (LiNiO ₂ ), and lithium nickel cobaltate (LiNi _1/2 Co _{1 / 2} O ₂ ), nickel cobalt lithium manganate (LiNi _1/3 Co _1/3 Mn _1/3 O ₂ ), and lithium iron phosphate (LiFePO ₄ ) can be preferably used. When metallic lithium is used as the lithium supply source, it is preferable to use the same metal foil as the negative electrode current collector, such as a copper foil, nickel foil, or stainless steel foil, as the lithium current collector. The size of the lithium current collector is not particularly limited, but a size similar to the negative electrode current collector size or a size slightly smaller (side length is 1 to 5 mm smaller) is preferably used. Metal lithium that has been cut in advance is bonded to a lithium current collector by a roll press or the like. At this time, it is preferable to previously form one extension portion in the lithium current collector, and to provide a portion for attaching the external terminal plate so as not to form metallic lithium.

  When a lithium-containing transition metal oxide is used as the lithium supply source, it is preferable to use the same metal foil as the positive electrode current collector, such as an aluminum foil or a stainless steel foil, as the lithium current collector. The size of the lithium current collector is not particularly limited, but a size similar to the positive electrode current collector size or a size slightly smaller (side length is 1 to 5 mm smaller) is preferably used. As an example of the manufacturing method, a lithium-containing transition metal oxide is used as a lithium supply source, polytetrafluoroethylene is used as a binder material, and ketjen black is used as a conductive agent. First, a lithium-containing transition metal oxide powder, a binder composed of polytetrafluoroethylene, and ketjen black are kneaded and then rolled to form a sheet-like lithium supply source. The sheet-like lithium supply source thus obtained is bonded to a roughened lithium current collector made of aluminum or stainless steel using a conductive carbon paste. Further, they are integrated by heating and drying, and this is used as a lithium supply plate. At this time, it is preferable to previously form one extension portion on the lithium current collector and to provide a portion to which the external terminal plate is attached so as not to form a lithium supply source.

  Also, instead of the above method, a metal lithium powder or lithium-containing transition metal oxide powder and a conductive agent are mixed and dispersed in a solution in which a binder such as methylcellulose or polyvinylidene fluoride is dissolved in a solvent. The lithium supply plate may be produced by a method of applying to the lithium current collector.

  Hereinafter, examples and comparative examples will be described. In addition, Examples 1-15 and Comparative Examples 1-5 produced a lithium ion capacitor as an electrochemical device, and Example 16 and Comparative Example 6 produced a lithium ion secondary battery, respectively, and performed various evaluations. .

Example 1
With respect to a powder obtained by mixing 92 parts by mass of a phenol-based activated carbon powder having a specific surface area of 1500 m ² / g as a positive electrode active material and 8 parts by mass of graphite as a conductive agent, 3 parts by mass of styrene-butadiene rubber as a binder and 3 parts by mass of carboxymethyl cellulose And 200 parts by mass of water as a solvent and kneaded to obtain a slurry. Next, an aluminum foil having a thickness of 20 μm whose both surfaces were roughened by etching treatment was used as a positive electrode current collector, and the slurry was uniformly applied to both surfaces thereof. Then, it was dried and rolled and pressed to form a positive electrode active material layer having a thickness of 30 μm to obtain a positive electrode. In addition, an extension part in which the aluminum foil extended in a tab shape was formed on a part of one short side of the positive electrode, and the positive electrode active material layer was not formed on both surfaces of the part, and the aluminum foil was exposed. .

  With respect to the powder obtained by mixing 88 parts by mass of the non-graphitizable material powder as the negative electrode active material and 6 parts by mass of acetylene black as a conductive agent, 5 parts by mass of styrene-butadiene rubber, 4 parts by mass of carboxymethyl cellulose, and 200 parts by mass of water as a solvent. And kneaded to obtain a slurry. Next, using the copper foil having a thickness of 10 μm as a negative electrode current collector, the slurry was uniformly applied on both surfaces thereof. Then, it was dried and rolled and pressed to form a negative electrode active material layer having a thickness of 20 μm to obtain a negative electrode. In addition, an extension part in which the copper foil extended in a tab shape was formed on a part of one short side of the negative electrode, and the negative electrode active material layer was not formed on both surfaces of the part, and the copper foil was exposed. .

  As a separator, a thin plate of a natural cellulose material having a thickness of 35 μm was used. The size and shape of the separator was configured to be slightly larger than the shape excluding the extended portion of each electrode.

  Subsequently, these three members were laminated in the order of a separator, a negative electrode, a separator, a positive electrode, and a separator to obtain an electrode body. One separator was always arranged on the outermost part of the electrode body. In this example, four stacked positive electrodes per sample, five negative electrodes, and 10 separators were formed. The dimensions excluding the extended portion were 88 mm × 128 mm for the positive electrode, 90 mm × 130 mm for the negative electrode, and 92 mm × 132 mm for the separator. Moreover, the extension part formed in each electrode extended from the different location of the same short side of each electrode, and the dimension of the extension part was 13.5 mm x 18 mm, respectively.

  As the positive electrode external terminal, an aluminum material having a length of 30 mm, a width of 15 mm, and a thickness of 0.2 mm was used. The negative electrode external terminal used was a Ni material plated on a copper material having a length of 30 mm, a width of 15 mm, and a thickness of 0.2 mm. The area derived from the exterior material was 15 mm long and 15 mm wide. For the surface to be thermally bonded to the exterior material, one having a sealant made of an acid-modified polyolefin resin applied on both sides was used. Next, the extending portions of the positive electrode and the negative electrode extending from the electrode body were bundled and collectively fixed to the end portions of the external terminals by ultrasonic welding.

  The lithium supply plate was prepared by bonding metal lithium as a lithium supply source to a lithium current collector made of a copper foil having a thickness of 10 μm. Moreover, the extension part was provided in a part of copper foil, and the external terminal for lithium supply plates was fixed by ultrasonic welding. The dimension excluding the extended portion of the lithium supply plate was 90 mm × 130 mm. At this time, the metallic lithium was bonded to the inner side with a length of 10 mm from the edge of three sides other than the side where the extending portion of the copper foil was provided with a thickness of 140 μm. The produced lithium supply plate was disposed in the upper part of the electrode body in the stacking direction in parallel with the electrode body. At this time, it arrange | positioned so that a lithium supply source may be located in the outer surface side of the outermost layer of an electrode body through a lithium electrical power collector. That is, a lithium current collector is interposed between the lithium supply source and the electrode body, and the arrangement of the lithium supply source is a non-facing surface of the electrode body.

  Next, the electrode body and the lithium supply plate are wrapped with two exterior materials, and the peripheral portions of the three sides including the short sides of the two sides on which the positive electrode external terminal and the negative electrode external terminal and the lithium supply plate external terminal are arranged are heated. Crimped into a bag. A 40 μm-thick thermoplastic resin layer made of an acid-modified polyolefin resin was formed on the inner surface of the exterior material, and the exterior material was joined by thermocompression bonding the thermoplastic resin layer.

  Further, an electrolyte was injected into the bag-shaped exterior material. As the electrolytic solution, a solution prepared by dissolving lithium hexafluorophosphate in a mixed solvent in which propylene carbonate and diethyl carbonate were mixed at a ratio of 1: 1 and adjusted to a concentration of 1.0 mol / l was used. After injecting the electrolytic solution, the remaining one side where the exterior material was not joined was sealed by thermocompression bonding in a vacuum atmosphere. Then, the external terminal for lithium supply plates and the negative electrode external terminal were electrically connected by welding, and lithium ions were occluded from the lithium supply plate into the negative electrode active material layer by an electrochemical method. The occlusion amount was 400 mAh / g with respect to the weight of the negative electrode active material layer. After completion of occlusion of lithium ions, a part of the exterior material was opened and the lithium supply plate was taken out. Further, it was thermocompression-bonded again in a vacuum atmosphere and sealed.

  A multilayer lithium ion capacitor was obtained by the above method. Fifty lithium ion capacitors were produced by this method.

(Comparative Examples 1-3: Structure of electrode)
In the same manner as in Example 1, 50 lithium ion capacitors were produced for each condition described below.

  Comparative Examples 1 and 2 apply the configuration of conventional electrodes (positive electrode and negative electrode). FIG. 7 is a plan view showing an electrode according to Comparative Example 1. FIG. FIG. 8 is a plan view showing an electrode according to Comparative Example 2. FIG. In Comparative Example 1, as shown in FIG. 7, an active material layer 17 a was formed using a current collector 17 b made of a punched punching metal, and an electrode 17 was produced. In Comparative Example 2, as shown in FIG. 8, an active material layer 18 a was formed by using a current collector 18 b made of an expanded metal obtained by machining a foil into a mesh (diamond shape), and an electrode 18 was produced. The manufacturing method used the same active material containing slurry as Example 1, and applied with the multicoater.

  In Comparative Example 1, the diameter of the through hole formed in the electrode was 1 mm, the hole area ratio was 30%, and the distance between the circle centers was 1.73 mm. In the lithium supply plate, the lithium current collector was arranged on the outer surface side of the outermost layer of the electrode body so that the lithium supply source faced the electrode body. This arrangement of the lithium supply source is defined as an opposing surface of the electrode body. 50 lithium ion capacitors were produced under the same conditions as in Example 1 except for the configuration of each electrode and the arrangement of the lithium supply plate.

  In Comparative Example 2, the aperture ratio of the opening formed in the electrode was 30%. Similarly to Comparative Example 1, a lithium supply plate was disposed, and a lithium supply source was disposed on the opposing surface of the electrode body. 50 lithium ion capacitors were produced under the same conditions as in Example 1 except for the configuration of each electrode plate and the arrangement of the lithium supply plate.

  Comparative Example 3 is a comparison with the present invention similar to the arrangement of a conventional lithium source. FIG. 9 is a plan view showing an electrode and a lithium supply source according to Comparative Example 3. In Comparative Example 3, a lithium supply source 12c made of metallic lithium was disposed on the surface side portion of the negative electrode current collector 19b of the negative electrode 19 separately from the negative electrode active material layer 19a. At this time, the size of the negative electrode 19 was 105 mm × 130 mm, and the size of the separator was 107 mm × 132 mm. The metallic lithium disposed on the side of the negative electrode current collector 19b was 10 mm × 130 mm and the thickness was 72 μm. The dimensions of the positive electrode were 88 mm × 128 mm as in Example 1. Further, since the lithium supply source 12c was disposed on the surface side portion of the negative electrode current collector 19b, the lithium supply plate used in Example 1 was not disposed. 50 lithium ion capacitors were produced under the same conditions as in Example 1 except for the configuration and dimensions of the negative electrode, the dimensions of the separator, and the arrangement of the lithium supply plate.

(Examples 2 to 5, Comparative Example 4: Size of lithium supply source)
In the same manner as in Example 1, 50 lithium ion capacitors were produced for each condition described below.

  In Examples 2 to 5 and Comparative Example 4, the formation position of the lithium supply source on the lithium supply plate was changed, and the other configurations were the same as in Example 1. Metallic lithium was formed inward from the edge of the three sides excluding the side where the extended portion of the lithium current collector was formed, and the formation length from the edge of the three sides was changed. The thickness was 5 mm in Example 2, 15 mm in Example 3, 20 mm in Example 4, 25 mm in Example 5, and 30 mm in Comparative Example 4. Here, the thickness of metallic lithium formed in Examples 2 to 5 and Comparative Example 4 was adjusted so that Example 1 and the volume (supply amount) of metallic lithium were the same.

(Example 6: Arrangement of lithium supply plate)
In the same manner as in Example 1, 50 lithium ion capacitors were produced for each condition described below.

  In Example 6, the lithium supply plates were disposed on the top and bottom surfaces of the electrode body in the stacking direction. At this time, the metal lithium of the lithium supply plate was half the thickness of Example 1. Metallic lithium was disposed on the non-facing surface of the electrode body.

(Examples 7 to 9: Arrangement of lithium supply source)
In the same manner as in Example 1, 50 lithium ion capacitors were produced for each condition described below.

  In Examples 7 to 9, the side to be formed when the lithium supply source was formed at the end of the lithium current collector was changed, and the other configurations were the same as in Example 1. In Example 7, the lithium current collector was disposed on one side of the long side, in Example 8, the long side was disposed on two sides, and in Example 9, the long side was disposed on four sides. At this time, it formed in the length of 10 mm from the edge of each side inside, and adjusted the thickness so that Example 1 and the volume of metallic lithium might become the same.

(Examples 10 to 15: Types of lithium supply source)
In the same manner as in Example 1, 50 lithium ion capacitors were produced for each condition described below.

In Examples 10 to 15, an aluminum foil having a thickness of 10 μm was used for the current collector of the lithium supply plate, the type of the lithium supply source was changed, and other configurations were the same as those in Example 1. Example 10 is LiMn ₂ O ₄ , Example 11 is LiCoO ₂ , Example 12 is LiNiO ₂ , Example 13 is LiNi _1/2 Co _1/2 O ₂ , and Example 14 is Li _1/3 Co _1/3. Mn _1/3 O ₂ Example 15 was LiFePO ₄ .

(Comparative Example 5: Arrangement of lithium supply source)
In the same manner as in Example 1, 50 lithium ion capacitors were produced for each condition described below.

  In Comparative Example 5, the lithium supply source was disposed on the opposing surface of the electrode body, and the other configurations were the same as in Example 1.

(Example 16, comparative example 6: kind of electrochemical device)
In Example 16, lithium cobalt oxide (LiCoO ₂ ) was used for the positive electrode active material layer, and a polyethylene-based separator was used for the separator. Except for these, 50 lithium ion secondary batteries were manufactured in the same manner using the same materials as in Example 1. In Comparative Example 6, the same expanded metal as in Comparative Example 2 was used for the positive electrode current collector and the negative electrode current collector. The same active material-containing slurry as in Example 16 was used for this current collector, and coating was performed with a multicoater to obtain an active material layer. Except for each current collector, 50 lithium ion secondary batteries were produced under the same conditions as in Example 16.

(Evaluation method)
The electrochemical devices produced in Examples 1 to 16 and Comparative Examples 1 to 6 were evaluated as follows. That is, four types of measurements, ie, insulation resistance measurement, direct current resistance (hereinafter referred to as DC-R) measurement, capacity measurement, and self-discharge measurement, and evaluation by calculation of volume energy density were performed.

Insulation resistance measurement was performed by applying a measurement voltage of 100 V and measuring insulation resistance using an insulation resistance measuring machine in a state where a contact pressure of 1 kg / cm ² per unit area was applied to the positive electrode external terminal and the negative electrode external terminal. The pass / fail judgment of the insulation resistance was determined to be 200 MΩ or higher. The defect rate was calculated from the number of defects relative to the number of evaluations.

  In the DC-R measurement, the electrochemical device was charged at a predetermined constant voltage for 1 hour with a charging / discharging device, and then the DC-R was measured when discharged at a current value of 20C. The DC-R selection standard is based on the comparative example 1 which is the prior art, and the average value of DC-R values measured for 20 samples (excluding obvious defective products) extracted from the comparative example 1 + 3σ or less. did. Those larger than the screening standard were regarded as defective, and the defect rate was calculated from the number of defects relative to the evaluation number. Since Example 17 and Comparative Example 5 are lithium ion secondary batteries, they were excluded from defective selection.

  In the capacity measurement, the electrochemical device was charged at a predetermined constant voltage for 1 hour with a charging / discharging device, and then the current capacity was measured when the electrochemical device was discharged at a current value of 20 C to the lower limit voltage. The capacity selection standard was set to 90% or more of the average capacity value measured for 20 samples (excluding obvious defective products) extracted from Comparative Example 1. Those smaller than the screening standard were regarded as defective, and the defect rate was calculated from the number of defects relative to the evaluation number. Since Example 17 and Comparative Example 5 are lithium ion secondary batteries, they were excluded from defective selection.

  Self-discharge measurement evaluation is performed after charging an electrochemical device at a predetermined constant voltage with a charging / discharging device for 1 hour, and then leaving the terminals open circuited and leaving the terminals at 60 ° C. for 72 hours in a constant temperature bath. The inter-voltage was measured. The selection standard for self-discharge was equal to or greater than the voltage average value −3σ measured for 10 samples (excluding obvious defective products) extracted from Comparative Example 1. The selection standard of the self-discharge of the lithium secondary battery was set to be equal to or higher than the voltage average value −3σ measured for 10 samples extracted from Comparative Example 4. Those smaller than the screening standard were regarded as defective, and the defect rate was calculated from the number of defects relative to the evaluation number.

  By the above method, four types of evaluations of insulation resistance measurement, DC-R measurement, capacity measurement, and self-discharge measurement were performed for each sample condition in Examples 1-16 and Comparative Examples 1-6. Table 1 shows the volume energy density calculated from the average capacity, average DC-R, overall failure rate, overall results, DC-R failure, insulation failure, self-discharge failure, and product size.

  In the examples of the present invention, good results were obtained in all of the evaluations of insulation resistance measurement, DC-R measurement, capacity measurement, and self-discharge measurement. Moreover, the favorable result was obtained also in the energy density per volume.

  In particular, in Example 1, the average value of DC-R is about 25% lower than that of Comparative Example 1, the resistance can be reduced, and the average value of volume energy density is about 7% higher than that of Comparative Example 3, and the high energy density is high. Was achieved. Since Example 1 does not have a through-hole in the current collector, current collection and contact resistance are superior to Comparative Example 1. Moreover, since Example 1 does not arrange | position a lithium supply source to the side surface of a negative electrode plate, size reduction of a product can be implement | achieved and a volume energy density is superior to the comparative example 3. Furthermore, in Example 1, since the energy loss at the time of discharge was improved by reducing the internal resistance, a higher capacity was obtained than in Comparative Example 1.

  Regarding Comparative Examples 1 and 2, burrs of through holes formed by machining occurred in the extended portions where the active material electrode layers of a plurality of electrodes were not formed, and there was an insulation failure between the electrodes via the separator. There was a sample generated. Moreover, the variation of DC-R was large, and a DC-R defect occurred.

  Lithium ion capacitor which does not cause capacity defect, DC-R defect, insulation defect, and self-discharge defect by arranging lithium supply source on the outer surface side (non-opposing surface) of the electrode body through a lithium current collector was gotten. In Comparative Example 1, Comparative Example 2, and Comparative Example 5 in which the lithium supply source is disposed so as to face the electrode body (opposite surface), voltage abnormality occurs in all cases, significant discoloration occurs on the surface of the opposing negative electrode, and lithium Metal lithium remained on the surface of the supply plate. This is presumed to be due to the following phenomenon. The negative electrode disposed near the outer layer of the electrode body adjacent to the lithium supply source and the negative electrode disposed near the center of the electrode body have different lithium ion movement distances and remarkably different movement resistances. . Therefore, excessive lithium ions are occluded in the negative electrode active material layer facing the lithium ion supply source. As a result, the potential is remarkably lowered as compared with other negative electrodes, and a voltage near the lithium oxidation-reduction potential is obtained, and it is considered that significant discoloration occurs on the electrode surface due to lithium deposition on the electrode surface. In the embodiment of the present invention, since the lithium supply source is arranged via the electrode body and the lithium current collector, the movement of lithium ions to each negative electrode active material layer is performed from the side surface in the stacking direction. There is no significant difference in the resistance of the negative electrode, and lithium ions are evenly occluded.

  As shown in Example 6, even when the lithium supply plates are arranged on the top and bottom surfaces of the electrode body, the non-facing surface of the electrode body is arranged so that the lithium supply source is arranged on the outer surface side through the lithium current collector. Good results were obtained by arranging them in the positions.

  Moreover, as shown in Example 1, Examples 2-5, Comparative Example 4, and Examples 7-9, the lithium supply source of the lithium supply plate is partially formed at the end of the lithium current collector. Preferably, the side to be formed can be selected as appropriate. In this example, the formation of a lithium supply source in the range of 25 mm or less from the edge of an arbitrary side of the lithium current collector did not cause capacity failure, DC-R failure, insulation failure, or self-discharge failure. . When the lithium current collector of Comparative Example 4 was formed 30 mm from the edge, the lithium metal on the lithium supply plate remained. This is presumed to be due to the following reasons. The movement of lithium ions is affected by the movement (diffusion) resistance in the electrolyte and the charge transfer resistance of the active material. These resistances tend to increase with increasing distance. Therefore, in Comparative Example 4, which is 30 mm or more from the edge of the lithium current collector, these resistances are increased, lithium ions are difficult to move, and metallic lithium remains.

  Further, as shown in Examples 13 to 15, even when the lithium supply source provided on the lithium supply plate was a lithium-containing transition metal oxide, no capacity failure, DC-R failure, insulation failure, or self-discharge failure occurred.

  Furthermore, as shown in Example 1, Example 16, and Comparative Example 6, the present invention can be applied to both a lithium ion capacitor and a lithium ion secondary battery. As shown in Example 16, in the lithium ion secondary battery as well as the lithium ion capacitor, no capacity failure, DC-R failure, insulation failure, or self-discharge failure occurred.

  Therefore, according to the present invention, it is possible to provide an electrochemical device having a reduced manufacturing cost, no self-discharge failure, a low internal resistance, and a good volume energy efficiency, and a manufacturing method thereof.

  Further, the description of each of the above examples is for explaining the effect in the case of the embodiment of the present invention, and thereby restricts the invention described in the claims or claims. It does not reduce the range. Moreover, each part structure of this invention is not restricted to said embodiment, A various deformation | transformation is possible within the technical scope as described in a claim.

100 Lithium Ion Capacitor 11 External Terminal 12 for Lithium Supply Plate Lithium Supply Plate 12a, 12c Lithium Supply Source 12b Lithium Current Collector 14 Separator 15 Electrode Body 16 Exterior Material 17, 18 Electrode 17a, 18a Active Material Layer 17b, 18b Current Collector 19, 32 Negative electrode 19a, 32a Negative electrode active material layer 19b, 32b Negative electrode current collector 21 Positive electrode external terminal 22 Positive electrode 22a Positive electrode active material layer 22b Positive electrode current collector 31 Negative electrode external terminal

Claims (11)

  An electrode body in which positive and negative electrodes each having an active material layer formed on at least one main surface of a first current collector made of metal foil are alternately stacked with a separator interposed therebetween, and lithium ions on the negative electrode An electrochemical device in which the electrode body and the lithium supply plate are sealed together with an electrolyte with an exterior material, wherein the lithium supply plate is made of a metal foil. A lithium supply source is formed on at least a part of one main surface of the electric body, and the lithium supply source includes the second current collector on at least one outer surface side of the outermost layer of the electrode body. Electrochemical device characterized by being arranged via.   The electrochemical device according to claim 1, wherein the lithium supply source is formed on the entire surface of one main surface of the second current collector.   The electrochemical device according to claim 1, wherein the lithium supply source is formed at an end of the second current collector.   The electrochemical device according to any one of claims 1 to 3, wherein the lithium supply source is metallic lithium or a lithium-containing transition metal oxide.   The lithium-containing transition metal oxide is selected from lithium manganate, lithium cobaltate, lithium nickelate, lithium nickel cobaltate, nickel cobalt lithium manganate, and lithium iron phosphate. 4. The electrochemical device according to 4.   A positive electrode and a negative electrode having an active material layer formed on at least one principal surface of a first current collector made of metal foil are alternately laminated via a separator to produce an electrode body, and lithium ions are applied to the negative electrode. A method for producing an electrochemical device comprising: a lithium supply plate that occludes lithium; and the electrode body and the lithium supply plate are sealed together with an electrolyte by an exterior material, wherein the lithium supply plate is made of a metal foil. A lithium supply source is formed on at least a part of one main surface of the current collector, and the lithium supply source is arranged on the outer surface side of at least one outermost layer of the electrode body. A method for producing an electrochemical device, wherein the method is arranged through a body. The method for producing an electrochemical device according to claim 6, wherein after the lithium ion is occluded in the negative electrode, the lithium supply plate is taken out of the exterior material.   8. The method of manufacturing an electrochemical device according to claim 6, wherein the lithium supply source is formed on the entire surface of one main surface of the second current collector.   The method for manufacturing an electrochemical device according to claim 6, wherein the lithium supply source is formed at an end portion of the second current collector.   The method for producing an electrochemical device according to any one of claims 6 to 9, wherein the lithium supply source is metallic lithium or a lithium-containing transition metal oxide.   11. The lithium-containing transition metal oxide is selected from lithium manganate, lithium cobaltate, lithium nickelate, nickel cobaltate lithium, nickel cobalt lithium manganate, and lithium iron phosphate. The manufacturing method of the electrochemical device as described in any one of.

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