JP5310450B2 - Non-aqueous electrochemical cell current collector and electrode using the same - Google Patents

Description

  The present invention is particularly suitable for a positive electrode current collector of a nonaqueous electrochemical cell such as a capacitor such as an electric double layer capacitor or a lithium ion capacitor, a nonaqueous electrolyte secondary battery such as a lithium ion battery or a lithium ion polymer battery. Further, the present invention relates to a composite of an aluminum plate and an aluminum porous sintered body, and an electrode using the same.

  In recent years, capacitors such as electric double layer capacitors and lithium ion capacitors, and non-aqueous electrolyte secondary batteries such as lithium ion batteries and lithium ion polymer batteries have come to be used in electric vehicles and hybrid vehicles. With the expansion of applications, the electrode current collectors in batteries are required to cope with higher output and improved cycle life. At present, aluminum foil is generally used as the positive electrode current collector of these non-aqueous electrochemical cells. As an electrode current collector, an aluminum porous body having open pores with a three-dimensional network structure is known. (Patent Documents 1 and 2).

  As a method for producing such an aluminum porous body, for example, after thickening molten aluminum with a thickener, titanium hydride is added as a foaming agent, and hydrogen gas generated by a thermal decomposition reaction of titanium hydride is used. There is known a foam melting method in which molten aluminum is solidified while being foamed (Patent Document 3). However, the foamed aluminum obtained by this method had large closed pores of several mm.

  In addition, as a second method, there is a method of obtaining foamed aluminum having a sponge skeleton by press-fitting aluminum into a mold having sponge urethane as a core and filling aluminum into a cavity formed by burning out urethane. According to this method, a foamed aluminum having a pore diameter of 40 PPI or less, that is, a pore diameter of 40 cells or less per inch (pore diameter: about 600 μm or more) is obtained.

Further, as a third method, there is a method in which aluminum is foamed by decomposition of TiH ₂ powder by heating and rolling a mixed powder of AlSi alloy powder and TiH ₂ powder between aluminum plate materials. The foamed aluminum to be obtained has a large pore diameter of several mm (Patent Document 4).

  Furthermore, as a fourth method, there is a method in which a metal having a eutectic temperature with aluminum lower than the melting point of aluminum is mixed with aluminum and heated and fired at a temperature higher than the eutectic temperature and lower than the melting point of aluminum. (Patent Document 5) The foamed aluminum obtained by the same method has a porosity as small as about 40% even if the pore diameter can be reduced. For this reason, the amount of the polarizable electrode material penetrating into the pores of the foamed aluminum as the current collector is small, and the desired high output and high energy density cannot be achieved.

  Therefore, among the above-mentioned methods, the second method can be adopted as a method for producing foamed aluminum having minute open pores that can achieve the purpose of high output and high energy density.

  However, even in this second method, in order to further reduce the pore diameter of the open pores, it is necessary to use fine sponge urethane, and the flow of aluminum becomes worse, making it impossible to press-fit or casting. Since the pressure becomes too high, it is difficult to produce foamed aluminum having a pore diameter smaller than 40 PPI.

  On the other hand, a foaming slurry containing metal powder and a foaming agent is used as a method for producing a high-porosity foam metal having small pore sizes and sized open pores in which a large number of minute open pores are evenly arranged. There is a slurry foaming method in which the material is foamed, dried and then sintered (Patent Document 6). According to this method, if a raw material powder that can be sintered is available, it is a high-porosity foam metal having dimensionally open pores having an arbitrary pore size ranging from about 10 PPI to about 500 PPI, that is, a pore size ranging from 2.5 mm to 50 μm. Can be easily manufactured. The slurry foaming method means a method in which a foamed metal is obtained by foaming by adding a foaming agent to a slurry containing metal powder, or by foaming by gas injection or stirring, drying, and sintering. .

  However, conventionally, in the slurry foaming method, it was difficult to produce foamed aluminum because non-pressure sintering of aluminum could not be performed due to the presence of an oxide film on the surface of the aluminum powder. Even if foamed aluminum can be manufactured, pure aluminum is soft, so the foamed aluminum breaks when rolling to increase the energy density after filling the pores with a polarizable electrode material. I am worried about it. Furthermore, for example, a high-power discharge at a discharge rate: several 10 to 100 C level is required for a hybrid type vehicle, and thermal stress due to heat generation due to a large current discharge increases, resulting in a short cycle characteristic. There is also a problem that it ends up.

Japanese Patent No. 3591055 JP 2009-43536 A Japanese Patent Application Laid-Open No. 08-209265 Special table 2003-520292 gazette Japanese Examined Patent Publication No. 61-48566 Japanese Patent No. 3535282

  The present inventors have found that by using a sintering aid containing titanium, it is possible to produce a high-strength aluminum porous sintered body by non-pressure sintering, and this aluminum porous sintering. An aluminum composite formed from a body and an aluminum plate was developed. In the present invention, this aluminum composite is used to collect current from a positive electrode of a non-aqueous electrochemical cell such as a capacitor such as an electric double layer capacitor or a lithium ion capacitor, a non-aqueous electrolyte secondary battery such as a lithium ion battery or a lithium ion polymer battery. It is an object of the present invention to provide a non-aqueous electrochemical cell having excellent cycle life when used as a body.

The present invention relates to a current collector for a positive electrode of a non-aqueous electrochemical cell and an electrode using the same, which have solved the above problems with the following configuration.
(1) A current collector made of an aluminum composite including an aluminum plate and an aluminum porous sintered body, wherein the aluminum porous sintered body has a metal skeleton having a three-dimensional network structure, and the metal skeleton A current collector for a positive electrode of a non-aqueous electrochemical cell, having pores in between and having an Al ₃ Ti compound dispersed in the metal skeleton.
(2) The current collector for a positive electrode of a nonaqueous electrochemical cell according to (1), wherein the aluminum plate has a thickness of 0.05 to 1 mm.
(3) The above, wherein the aluminum porous sintered body contains 0.2 to 2 parts by mass of nickel and 0.1 to 20 parts by mass of titanium with respect to 100 parts by mass of aluminum, nickel and titanium in total ( The collector for positive electrodes of the non-aqueous electrochemical cell as described in 1) or (2).
(4) A polarizable electrode material and a binder are included in the pores of the aluminum porous sintered body of the positive electrode current collector of the nonaqueous electrochemical cell according to any one of (1) to (3) above, A positive electrode of a non-aqueous electrochemical cell, characterized in that a metal skeleton part of a three-dimensional network structure of an aluminum porous sintered body is consolidated.

According to the present invention (1), an aluminum composite comprising a high-strength aluminum porous sintered body and an aluminum plate by dispersion of an Al ₃ Ti-based compound has high strength. By allowing the pores to contain the polarizable electrode material and then rolling, the aluminum porous sintered body of the aluminum composite as the current collector can be brought into close contact with the polarizable electrode material and the binder. Since the aluminum plate has good conductivity and high thermal conductivity, it can provide a positive electrode of a non-aqueous electrochemical cell having a high output density and particularly excellent cycle characteristics.

It is a scanning electron micrograph of the aluminum porous sintered compact of the aluminum complex of an Example. 2 is a partially enlarged scanning electron micrograph of FIG. 3 is a partially enlarged scanning electron micrograph of FIG. It is a conceptual diagram of the electrical power collector for positive electrodes of this invention. It is a schematic diagram of the structure of the test cell produced in the Example, the comparative example, and the prior art example. It is a figure explaining the preparation methods of a positive electrode current collection tab.

  Hereinafter, the present invention will be specifically described based on embodiments. Unless otherwise indicated,% is based on mass unless otherwise specified.

[Current collector for positive electrode of non-aqueous electrochemical cell]
The positive electrode current collector of the non-aqueous electrochemical cell of the present invention comprises an aluminum composite comprising an aluminum plate and an aluminum porous sintered body, and the aluminum porous sintered body is a sintered metal skeleton (hereinafter referred to as “sintered metal skeleton”). , Referred to as a metal skeleton), and having inter-frame vacancies, which are spaces surrounded by the metal skeleton, and intra-skeleton vacancies formed in the metal skeleton itself, and An Al ₃ Ti compound is dispersed in the metal skeleton. Here, the non-aqueous electrochemical cell refers to an electrochemical cell using a non-aqueous electrolyte, such as an electric double layer capacitor or a lithium ion capacitor, a non-aqueous electrolyte battery such as a lithium ion battery or a lithium ion polymer battery. A secondary battery etc. are mentioned.

  The aluminum plate constituting the aluminum composite of the present invention preferably has a thickness of 0.05 to 1 mm from the viewpoint of the strength of the aluminum composite, the output density of the electrode, and the heat capacity of the aluminum plate.

  FIG. 1 shows a scanning electron micrograph of the aluminum porous sintered body of the aluminum composite before rolling produced in the example, FIG. 2 shows a partially enlarged scanning electron micrograph of FIG. 1, and FIG. FIG. 3 shows a partially enlarged scanning electron micrograph of FIG. As apparent from FIGS. 1, 2, and 3, the porous aluminum sintered body forms pores by a metal skeleton having a three-dimensional network structure. In addition, the metal skeleton itself has a feature of high porosity.

  The aluminum porous sintered body contains aluminum and titanium, and preferably further contains nickel. Here, it is preferable that the aluminum porous sintered body includes 0.2 to 2 parts by mass of nickel and 0.1 to 20 parts by mass of titanium with respect to 100 parts by mass in total of aluminum, nickel, and titanium. . If the nickel content is 0.2 to 2 parts by mass, the melting point of the raw material powder containing aluminum, nickel, and titanium is lowered, so that the sintering temperature can be less than 660 ° C., and the aluminum plate is melted during sintering. Can be avoided. Moreover, when titanium is less than 0.1 part by mass, a good aluminum porous sintered body cannot be obtained, and when it exceeds 20 parts by mass, it becomes brittle and a desired porous sintered body cannot be obtained. Become. Here, quantitative analysis of aluminum, nickel, and titanium is performed by the ICP method.

  In FIG. 4, the conceptual diagram of the electrical power collector for positive electrodes of this invention is shown. As shown in the right part of FIG. 4, the aluminum composite of the present invention has a portion where the aluminum plate and the aluminum sintered body are joined. Preferably, as shown in the left part of FIG. There is also a portion of an aluminum plate where the aluminum sintered body is not in close contact.

[Nonaqueous Electrochemical Cell Electrode]
The electrode of the non-aqueous electrochemical cell of the present invention includes a polarizable electrode material and a binder in the pores of the aluminum porous sintered body of the positive electrode current collector, and the three-dimensional aluminum porous composite. The metal skeleton part of the network structure is compacted. Here, the compaction means that the pores of the aluminum porous sintered body are deformed and increased in density by, for example, pressure such as rolling or pressing.

  Hereinafter, the case of the electric double layer capacitor electrode will be described. Examples of the polarizable electrode material contained in the pores of the porous aluminum sintered body include those used as polarizable electrode materials for electric double layer type capacitors, which can be polarized in an electrolyte. If there is, it will not be specifically limited. Conventionally, it is sufficient if it is generally used, and specifically, activated carbon having nano-sized pores is preferable. The polarizable electrode material is preferably a powder having an average particle size of 2 to 20 μm from the viewpoint of increasing the output of the electric double layer capacitor. Here, the average particle diameter is measured by a laser diffraction method.

  Examples of the binder include, but are not limited to, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), SBR, and polyimide.

  When used as an electrode for a lithium ion capacitor, the polarizable electrode material or the like may be replaced with one known to those skilled in the art for a lithium ion capacitor.

  The positive electrode current collector of the non-aqueous electrochemical cell of the present invention can be produced as follows.

  First, an aluminum mixed raw material powder is prepared by mixing titanium powder and / or titanium hydride powder with aluminum powder to obtain an aluminum mixed raw material powder (aluminum mixed raw material powder preparation step). Here, the aluminum mixed raw material powder preferably further contains nickel. The aluminum mixed raw material powder is mixed with a water-soluble resin binder, water, and a plasticizer to prepare a viscous composition (viscous composition preparation step). The viscous composition is dried in a state where air bubbles are mixed to form a pre-sintered molded body (pre-sintering process), and the pre-sintered molded body is 630 (° C.) ≦ heating and firing temperature (non-oxidizing atmosphere) T) <660 (° C.) and heat firing (sintering process).

  The sintering aid containing titanium preferably contains 0.1 to 20 parts by mass of titanium with respect to 100 parts by mass in total of aluminum, nickel and titanium, and the sintering aid containing nickel contains aluminum, nickel It is preferable to contain 0.2-2 parts by mass of nickel with respect to 100 parts by mass in total of titanium. Here, the average particle diameter of the nickel powder is desirably smaller than the average particle diameter of aluminum. For example, the average particle diameter is preferably 0.5 μm to 3 μm, more preferably 0.8 μm to 2 μm. If the amount of nickel powder is too small, the effect of promoting the sintering will not be exhibited. On the other hand, if the amount is too large, coarse particles of visible droplet spherical aluminum having a diameter of 0.5 mm or more are generated in the sintered body. Therefore, the blending amount of nickel powder is preferably 0.2 to 2 parts by mass, more preferably 0.4 to 1.4 parts by mass.

  The average particle size of titanium hydride is preferably 0.1 (μm) ≦ r ≦ 30 (μm), more preferably 4 (μm) ≦ r ≦ 20 (μm). This is because if the average particle size of titanium hydride is smaller than 0.1 μm, spontaneous ignition may occur, and if it exceeds 30 μm, desired strength cannot be obtained in the sintered body.

  The blending amount of titanium hydride is preferably 0.1 (mass%) ≦ W ≦ 20 (mass%). If the amount is less than 0.1% by mass, the sintering becomes insufficient. On the other hand, if the blending ratio W of the sintering aid powder exceeds 20% by mass, the sintered body becomes brittle and the desired porous sintered body is obtained. It is because it becomes impossible to obtain.

  Next, in the viscous composition preparation step, a water-soluble resin binder, a plasticizer, distilled water, and a surfactant are added to the aluminum mixed raw material powder, respectively.

  And after kneading | mixing these, it is made to foam by mixing a C5-C8 water-insoluble hydrocarbon-type organic solvent, and the viscous composition with which the bubble was mixed is adjusted. As the water-insoluble hydrocarbon organic solvent having 5 to 8 carbon atoms, at least one selected from the group consisting of pentane, hexane, heptane and octane can be used.

  In the next pre-sintering step, after applying the viscous composition to the strip-shaped aluminum foil by a doctor blade method, a slurry extrusion method or a screen printing method so as to have a thickness of 0.05 mm to 5 mm, Ambient temperature and humidity are controlled for a certain period of time to size the bubbles and then dried at 70 ° C. in an air dryer. Here, from the viewpoint of mechanical strength, the thickness of the aluminum foil is preferably 10 μm or more and less than 50 μm, and more preferably 15 μm or more and 25 μm or less.

  And the viscous composition after drying is cut out to desired shape with aluminum foil, and the aluminum foil side is mounted on the aluminum plate of desired shape, and a pre-sintered molded object is obtained. By making aluminum foil exist on an aluminum plate, when aluminum mixed raw material powder shrink | contracts at the time of sintering, aluminum foil can be slid on an aluminum plate and the crack of an aluminum porous sintered compact can be prevented.

  In the next sintering step, the above-mentioned pre-sintered compact is placed on an alumina setter coated with a powder such as zirconia and heated at 520 ° C. for 1 hour in an argon atmosphere with a dew point of −20 ° C. or lower. Pre-baking is performed. As a result, debinding that volatilizes and / or decomposes the binder solution of the water-soluble resin binder component, plasticizer component, distilled water, and surfactant in the pre-sintered molded body is performed, and hydrogen is used as the sintering aid powder. When titanium fluoride is used, dehydrogenation is performed.

  Thereafter, the pre-sintered shaped body after temporary firing is heated and fired at 630 (° C.) ≦ heating and firing temperature (T) <660 (° C.) to obtain an aluminum composite.

  In addition, in order to suppress the growth of the oxide film on the surface of an aluminum particle, the surface of a titanium particle, and the surface of a nickel particle, it is necessary to perform the heat baking in a sintering process in non-oxidizing atmosphere. However, if the heating temperature is 400 ° C. or lower and maintained for about 30 minutes, the oxide film on the aluminum particle surface, titanium particle surface and nickel particle surface does not grow much even when heated in air. The formed compact may be heated and held at 300 ° C. to 400 ° C. in air for about 10 minutes to remove the binder, and then heated and fired at a predetermined temperature in an argon atmosphere.

  Here, the non-oxidizing atmosphere means an atmosphere that includes an inert atmosphere or a reducing atmosphere and does not oxidize the aluminum mixed raw material powder. In addition, the above-described heating and firing temperature is not the temperature of the aluminum mixed raw material powder, that is, does not measure the reaction temperature of the aluminum mixed raw material powder, but means the holding temperature around the aluminum mixed raw material powder. .

  The aluminum porous sintered body of the aluminum composite obtained in this manner has a metal skeleton with a three-dimensional network structure, has pores between the metal skeletons, and is almost uniformly in the metal sintered body. Al—Ti compound is dispersed. When used for an electric double layer capacitor, the positive electrode current collector of the present invention can also be used as a negative electrode current collector.

  The electrode of the non-aqueous electrochemical cell of the present invention has a polarizable electrode in the pores of a current collector made of an aluminum composite including an aluminum plate and an aluminum porous sintered body having a metal skeleton having a three-dimensional network structure. The slurry containing the material and the binder can be filled, dried and then rolled.

[Method of manufacturing positive electrode for capacitor]
As an example of a detailed method for producing an electrode of a non-aqueous electrochemical cell of the present invention, a method for producing a capacitor electrode is disclosed below.

  The slurry containing the polarizable electrode material and the binder can be obtained, for example, as follows. First, the binder is dissolved or uniformly dispersed in an organic solvent. This mixed solution and polarizable electrode material are mixed to form a slurry. Alternatively, there is a method of uniformly mixing the polarizable electrode material and the binder and then adding an organic solvent to form a slurry, but is not particularly limited. At this time, the apparatus to be used may be those normally used by those skilled in the art, such as a planetary mixer, a ball mill, and a Henschel mixer. Here, the organic solvent has a viscosity that allows the slurry to be easily immersed in the aluminum porous sintered body in the step of immersing the next aluminum porous sintered body in the slurry, for example, 10 to 60 Pa · s. It is preferable to add. In addition, you may add conductive support agents, such as carbon black, acetylene black, and ketjen black, to the said slurry.

  Examples of the organic solvent for dissolving or dispersing the binder include tetrahydrofuran (hereinafter referred to as THF), methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, N-methylpyrrolidone, acetone, acetonitrile, dimethyl carbonate, ethyl acetate, butyl acetate, and the like. Although it can be used, in order to selectively remove this organic solvent by drying, a volatile organic solvent having a boiling point of 100 ° C. or lower such as THF or acetone, or N-methylpyrrolidone having a high ability to dissolve a binder is preferable.

  Next, the pores of the aluminum porous sintered body of the aluminum composite are filled with a slurry of polarizable electrode material and dried. Examples of the filling method include a method of dipping into a slurry of polarizable electrode material with the aluminum porous sintered body facing down, a method of pouring the slurry from the upper part of the aluminum porous sintered body, and the like. By passing the slurry of excess polarizable electrode material adhering to the surface by passing between rolls or rubbing with a spatula, the polarizable electrode material is more effectively put into the pores of the porous aluminum sintered body. Can be filled. Drying may be left in the air, or a dryer or the like may be used. After drying, measure the mass ratio of the aluminum composite to the polarizable electrode material and the binder. If the mass ratio of the polarizable electrode material and the binder is low, repeat immersion and drying again to obtain the desired amount. can do. On the other hand, when the mass ratio of the polarizable electrode material and the binder is high, the viscosity of the slurry can be lowered, and dipping and drying can be performed again to obtain a desired amount.

Next, the aluminum composite containing the polarizable electrode material and the binder is rolled to obtain a capacitor electrode. In the aluminum composite of the present invention, an Al ₃ Ti compound is dispersed in the metal skeleton of the aluminum porous sintered body, and the aluminum porous sintered body alone has high strength, particularly tensile strength, and an aluminum plate Thus, the aluminum composite can be rolled to a desired thickness, the porosity of the electrode body can be reduced, and the electrode density can be increased. Here, the electrode thickness is preferably 0.03 to 3 mm. Here, the density of the aluminum composite can also be increased by pressing or the like, but rolling is preferred from the viewpoint of productivity.

  The capacitor electrode described above is effectively used as an electric double layer capacitor and a lithium ion capacitor having high output density and excellent cycle characteristics. In addition, when using for an electric double layer type capacitor, it can be used also as an electrode for negative electrodes. Moreover, it can be used also as a positive electrode of a lithium ion battery or a lithium ion polymer battery.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these.

[Production of porous aluminum sintered body]
According to the above-described embodiment, an aluminum porous sintered body was manufactured. First, an aluminum powder having an average particle diameter of 24 μm (including impurities: Fe: 0.15 mass%, Si: 0.05 mass% and Ni: 0.01 mass%), and nickel powder having an average particle diameter of 1 μm The titanium hydride powder having an average particle diameter of 9.1 μm is mixed in a total of 500 g so that the mass ratio of the aluminum powder, the nickel powder and the titanium hydride powder is 94: 1: 5 to prepare an aluminum mixed raw material powder. did.

  Binder solution: 100 parts by mass of binder solution: 0.1 parts by mass of methyl cellulose, 2.9 parts by mass of ethyl cellulose, 3 parts by mass of glycerin, 3 parts by mass of polyethylene glycol, 0.5 parts by mass of alkyl betaine It was prepared in a total of 500 g at a ratio of part and remaining water.

  Aluminum mixed raw material powder: 50 parts by mass, binder solution: 49 parts by mass, and hexane: 1 part by mass were mixed in a total of 500 g to prepare a viscous composition.

  Next, this viscous composition is stretched and applied onto an aluminum foil having a thickness of 20 μm by a doctor blade method, and the temperature and humidity are controlled to be maintained for a certain period of time. It dried at the temperature of 70 degreeC with the dryer. The coating thickness of the viscous composition at this time was 0.35 mm, the temperature was 35 ° C., the humidity was 90 minutes, and the holding time was 20 minutes. Subsequent drying was performed at 70 ° C. for 50 minutes. And the viscous composition after drying was cut out to the rectangle of 50 mm x 70 mm with aluminum foil, and it mounted on the aluminum plate of thickness: 0.5 mm and 60 mm x 90 mm, and obtained the compact before sintering.

This pre-sintered compact was pre-baked (debindered) in an argon stream atmosphere and then heated and fired to obtain an aluminum composite 1. Debinding was performed at 520 ° C. for 30 minutes. Heating and baking were performed at 650 ° C. for 30 minutes in an argon atmosphere to obtain an aluminum composite. In the obtained aluminum composite, the aluminum porous body part was sintered and contracted to 45 mm × 63 mm and joined to the aluminum plate, and the total thickness of the aluminum porous body joined part was 1.2 mm. As a result of observing an aluminum porous sintered body portion (hereinafter referred to as “aluminum porous sintered body”) of the aluminum composite by X-ray diffraction, Al and Al ₃ Ti compounds were confirmed.

[Manufacture of electrodes for electric double layer capacitors]
Example 1
Activated carbon powder as a polarizable electrode material, ketjen black (KB) as a conductive material, and polyvinylidene fluoride (PVDF) as a binder at a mass ratio of 80:10:10, a total of 200 g is mixed to prepare an electrode agent. The electrode material was mixed with 162 g of N-methyl-2pyrrolidone as a solvent to prepare a polarizable electrode material slurry.

  Next, the produced aluminum porous sintered body was immersed in this polarizable electrode material slurry for 10 minutes, taken out and dried, and then rolled and rolled into an electric double layer type capacitor of Example 1 having a thickness of 0.5 mm An electrode was prepared. Here, after the aluminum porous sintered body is immersed in the polarizable electrode material slurry, dried, and before rolling, the polarizable electrode material slurry adhering to the surface of the aluminum porous sintered body is wiped off, and almost the entire amount is obtained. The polarizable electrode material, the conductive aid and the binder were included in the pores of the aluminum porous sintered body.

(Examples 2 and 3)
In the same manner as in Example 1, the polarizable electrode material slurry was immersed and dried twice, and the electrode of the electric double layer capacitor of Example 2 was also immersed and dried in the polarizable electrode material slurry. The electrode of the electric double layer type capacitor of Example 3 was produced.

(Conventional example 1)
As the foamed aluminum of Conventional Example 1, 30 PPI foamed aluminum produced by press-fitting aluminum into a mold having sponge urethane as a core, which is the second method of the prior art, was used.

  The electric double layer capacitor of Conventional Example 1 having a thickness of 0.5 mm after being immersed in the polarizable electrode material slurry produced in Example 1 for 10 minutes, and then taken out and dried, and rolled. An electrode was prepared.

[Performance test of electrode for electric double layer type capacitor]
(Discharge capacity)
In order to measure the energy density, a test cell of an electric double layer capacitor was fabricated. FIG. 5 shows a schematic diagram of the configuration of the test cell used.

  Next, the positive electrode 10 having the positive electrode current collecting tab 10a was produced as follows. As shown in FIG. 6 (A), each of the above-mentioned electrodes includes a portion for forming the positive electrode current collecting tab 10a and contains the polarizable electrode material portion 20, and is compacted by rolling to be an aluminum porous sintered body portion. Was cut into a width of 30 mm and a length of 50 mm so as to include 30 mm × 40 mm. As shown in FIG. 6B, after making a cut 21 having a length of 25 mm and a width of 5 mm on one side of the positive electrode 10, the folding line 22 is folded into a valley and the folding line 23 is folded into a mountain to produce the positive electrode current collecting tab 10 a. did. Similarly, the negative electrode 11 having the negative electrode current collecting tab 11a was produced. As the separator 12, a polypropylene microporous membrane (thickness: 20 μm) separator 12 was cut into a width of 32 mm and a length of 47 mm. These were laminated in order of the negative electrode current collection tab 11a, the negative electrode 11, the separator 12, the positive electrode 10, and the positive electrode current collection tab 10a, and the laminated body was produced.

  The welded portions 13c on the three sides of the pair of aluminum laminate films 13a and 13b, which were cut to a size that can accommodate the laminated body, were heat-sealed to obtain an exterior body 13.

In an inert atmosphere, the laminate is inserted through the opening of the exterior body 13, and the laminate is accommodated in the exterior body 13, and 1.5 M (C ₂ H ₅ ) ₃ CH ₃ NBF ₄ / PC After injecting the nonaqueous electrolyte, the opening of the outer package 13 was heat-sealed and sealed to prepare a test cell.

  The test cell was charged / discharged at a charge / discharge rate of 0.2C and a charge / discharge voltage of 0 to 2.5V. Table 1 shows the results of the discharge capacity.

(Output characteristics)
The test cell was charged / discharged at a charge / discharge rate of 100C and a charge / discharge voltage of 0 to 2.5V. Table 1 shows the results of these discharge capacities.

(Cycle characteristics)
The above test cell was subjected to a cycle test under the conditions of charge / discharge rate: 100 C, charge / discharge voltage: 0 to 2.5 V, with “charge → rest: 5 minutes → discharge → rest: 5 minutes” as one cycle. . Table 1 shows the results of the discharge capacity after 500 cycles. In addition, [“discharge capacity after 500 cycles” / “initial discharge capacity”] was defined as a capacity maintenance rate (unit: “%”). Table 1 shows the results of the capacity retention rate.

  As can be seen from Table 1, the test cells using the electrodes of Examples 1 to 3 are capable of high power discharge at 100 C, and the capacity retention rate is 91 to 92% even after 100 cycles. showed that. In contrast, Comparative Example 1 was inferior in capacity retention rate of 78%.

  As described above, it has been found that the electric double layer type capacitor of the present invention can produce an electric double layer type capacitor having high output and excellent cycle life.

DESCRIPTION OF SYMBOLS 10 Positive electrode 10a Positive electrode current collection tab 11 Negative electrode 11a Negative electrode current collection tab 12 Separator 13 Exterior body 13a, 13b Aluminum laminate film 13c Welding part 20 Minute polar electrode material part

Claims (3)

A current collector made of an aluminum composite comprising an aluminum plate and an aluminum porous sintered body,
The aluminum porous sintered body is manufactured by pressureless sintering using nickel and titanium as a sintering aid, and 0.2 to 2 nickel is added to 100 parts by mass of aluminum, nickel, and titanium in total. Including 0.1 to 20 parts by mass of titanium and titanium,
The aluminum porous sintered body has a metal skeleton having a three-dimensional network structure, has pores between the metal skeletons, and an Al ₃ Ti compound is dispersed in the metal skeleton. A current collector for a positive electrode of a non-aqueous electrochemical cell.   The current collector for a positive electrode of a non-aqueous electrochemical cell according to claim 1, wherein the aluminum plate has a thickness of 0.05 to 1 mm. A three-dimensional aluminum porous sintered body comprising a polarizable electrode material and a binder in the pores of the aluminum porous sintered body of the positive electrode current collector of the nonaqueous electrochemical cell according to claim 1 or 2. A positive electrode of a non-aqueous electrochemical cell, characterized in that a metal skeleton portion having a network structure is consolidated.