JP3058157B1 - Method for producing electrode for battery, electrode for battery and secondary battery - Google Patents

Abstract

The present invention aims to increase the capacity per unit area and increase the ratio of the electrode to the entire battery, and to facilitate the increase in the size of the battery. It is an object to provide a secondary battery. A film forming step of forming an electrode by forming an electrode mixture containing a polymer as an active material on a current collector, and a dividing step of dividing the formed electrode into a plurality of predetermined portions. ,
Performing a drying step of drying the electrode divided into a plurality of portions in an atmosphere at a predetermined temperature to increase the capacity per unit area and increase the proportion of the electrode in the entire battery, thereby easily increasing the size of the battery. A battery electrode is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a secondary battery technology, and more particularly, to the manufacture of a battery electrode for increasing the capacity per unit area and increasing the ratio of the electrode to the entire battery, thereby facilitating the enlargement of the battery. The present invention relates to a method, a battery electrode, and a secondary battery.

[0002]

2. Description of the Related Art Polymers as a battery active material have been extensively studied and developed since they have the following advantages. First, the molecular design is free, and it is easy to change the physical properties by changing the functional groups and the degree of polymerization.
Second, a light, thin, and flexible battery having excellent workability can be manufactured. Third, the number of reaction electrons is large and the capacity (unit is mAh · g ⁻¹ ) is large. For example,
Polypyridine can achieve a capacity of about 348 mAh · g ⁻¹ , and poly 1,5-diaminoanthraquinone has a capacity of about 33
A capacity of 8 mAh · g ⁻¹ can be realized (first prior art). When a polymer is used as an active material, for example, using a mask having a divided pattern in advance, a film is formed in a state where the electrodes are divided, and then dried at a temperature of about 120 ° C. It was possible to produce an electrode (second prior art). Further, as a conventional technique for preventing power generation performance deterioration and cracking of a power generation film, for example, there is a technique disclosed in Japanese Utility Model Laid-Open No. 6-70162 (third conventional technique). That is, the third prior art is
A solid electrolyte fuel cell having a power generation membrane in which an air electrode is formed on one side and a fuel electrode is formed on the other side. In the third prior art, since the thermal expansion coefficients of the solid electrolyte layer and the electrode layer are different, cracking and peeling of the electrode are likely to occur due to temperature change during firing or operation, and it is considered that the power generation performance is deteriorated. Is baked in a state of being applied on a solid electrolyte, and then divided into a plurality of regions. Further, electrodes are formed on the solid electrolyte layer (ion conductor). This can prevent the power generation film (= electrode) from cracking due to temperature change during firing or operation, and prevent the power generation film (= electrode) from warping or peeling from the solid electrolyte due to temperature change during firing or operation. In addition, power generation performance caused by cracking of the power generation film (= electrode) due to temperature change during firing or operation, warpage of the power generation film (= electrode) due to temperature change during firing or operation, or separation from the solid electrolyte It is disclosed that it has a function of preventing deterioration.

[0003]

However, in the polymer as the battery active material in the first prior art, since the polymer molecules swell or dissolve in the solvent, the volume shrinkage accompanying the removal of the solvent during drying is large. When an electrode mixture consisting of a polymer as an active material or a conductive agent, a binder and a solvent is formed and dried, the electrodes are integrally shrunk as a whole, causing strain during drying of the electrodes, causing cracks and cracks in the electrodes. As a result of peeling off from the electric body, there is a problem that it is difficult to increase the thickness of the electrode containing the polymer or increase the size of the electrode.

In the second prior art, when the capacity of a battery is increased by enlarging the area while keeping the film thin, the area of the current collector and the separator increases as well as the area of the electrode, and the amount of the electrolyte increases. There is a problem that the ratio of the electrode to the whole volume of the battery is small, and it is difficult to increase the capacity.

The third prior art mentions prevention of deterioration in power generation performance of a solid electrolyte fuel cell and prevention of cracks in a power generation film. However, the electrode thickness in a secondary battery is increased to increase the proportion of the electrode in the entire battery. It does not disclose that the size of the electrode is increased and the size of the battery is easily increased. The present invention has been made in view of such problems, and aims to increase the capacity per unit area and increase the ratio of electrodes to the entire battery,
An object of the present invention is to provide a battery electrode manufacturing method, a battery electrode, and a secondary battery that facilitate the upsizing of a battery.

[0006]

SUMMARY OF THE INVENTION The gist of the present invention is to increase the capacity per unit area and increase the ratio of the electrode to the whole battery, thereby facilitating the enlargement of the battery. An electrode manufacturing method, comprising: forming a film by forming an electrode mixture containing a polymer as an active material on a current collector to form an electrode; and dividing the formed electrode into a plurality of predetermined portions. includes a dividing step of, a drying step of drying the electrode divided into the plurality of portions within a predetermined temperature atmosphere, the
The polymer used for the active material is capable of absorbing and desorbing protons and / or
Or doping and dedoping of ions other than protons
The present invention relates to a method for producing an electrode for a battery, characterized by comprising a polymer compound which causes an oxidation-reduction reaction associated with the step. Further, the gist of the invention according to claim 2 is a method for manufacturing a battery electrode for increasing the capacity per unit area and increasing the proportion of the electrode in the whole battery, and facilitating the enlargement of the battery. A film forming step of forming an electrode by forming an electrode mixture containing a polymer as a conductive material on a current collector; a dividing step of dividing the formed electrode into a plurality of predetermined portions; Drying the electrode divided into portions in an atmosphere at a predetermined temperature , wherein the polymer used for the conductive material is
A chain with π conjugation and a given conductivity
The present invention resides in a method for producing an electrode for a battery, characterized by containing a secondary compound . The gist of the invention described in claim 3 is that the film forming step includes a step of applying the electrode mixture on the current collector by a printing method. The method for producing a battery electrode described above is provided. Claims
The gist of the invention described in 4 is an electrode structure for a battery, which increases the capacity per unit area and the ratio of the electrode to the entire battery, and facilitates upsizing of the battery. forming a electrode mixture on a current collector including the
After the film is formed, the electrode is divided into a plurality of portions and then dried.
Has electrodes, a polymer used for the active material, characterized in that it comprises absorption and desorption of protons, and / or other except proton-doped as well as high molecular compound to produce a redox reaction accompanied by undoping of ions The battery electrode structure. The gist of the invention described in claim 5 is an electrode structure for a battery that increases the capacity per unit area and the ratio of the electrode to the entire battery, and facilitates the enlargement of the battery. An electrode mixture containing a polymer as a material is formed on a current collector , and the formed electrode is divided into a plurality of portions.
And a dried electrode, wherein the polymer used for the conductive material contains a polymer compound having π-conjugated molecular main chain and predetermined conductivity. The gist of the invention described in claim 6 is to increase the capacity per unit area and increase the ratio of the electrode to the whole battery, and to facilitate the increase in the size of the battery. In the battery electrode structure, the electrode mixture containing a polymer as an active material is formed on a current collector , and the formed electrode is formed in a plurality of portions.
A polymer which has an electrode which has been divided and then dried , wherein the polymer used for the active material includes a polymer compound which causes adsorption / desorption of protons and / or doping and dedoping of ions other than protons and an oxidation-reduction reaction accompanying the doping A secondary battery characterized by the above. The gist of the invention described in claim 7 is that a secondary battery having a battery electrode structure that increases the capacity per unit area and the ratio of the electrode to the entire battery, and facilitates upsizing of the battery. In the battery electrode structure, an electrode mixture containing a polymer as a conductive material is formed on a current collector , and the formed electrode is divided into a plurality of portions.
A secondary battery having an electrode which has been cracked and then dried , wherein the polymer used for the conductive material contains a polymer compound having π-conjugated molecular main chain and predetermined conductivity.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The features of each embodiment described below are as follows.
An electrode mixture containing a polymer as an active material or a conductive material is formed on a current collector (electron conductor), and the formed electrode is divided into a plurality of portions and then dried. This makes it possible to reduce cracking and peeling of the electrode, which is considered to be mainly caused by volume change (shrinkage) due to evaporation of the solvent during electrode drying. In addition, as a result of making it possible to increase the thickness of the electrode, the capacitance per unit area (mAh · c
m ⁻² ) can be increased, and the ratio of the electrode to the entire battery can be increased. At the same time, it is possible to increase the size of the electrode, and as a result, it is possible to easily increase the size of the battery. Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First Embodiment) As a polymer used for an active material, a polymer compound which causes an adsorption / desorption of protons or a redox reaction accompanying doping and / or undoping of other ions is used. Examples of the polymer compound involved in proton adsorption and desorption include a polymer having an amino group in the molecule such as polyaniline or a derivative thereof, polypyrrole, polypyridine, or a nitrogen-containing compound such as polypyrimidine or a derivative thereof, anthraquinone, benzoquinone, or the like. A polymer of a compound having a quinoid structure or a derivative thereof is used.

Examples of the high molecular compound involved in doping and / or undoping of ions other than protons include polythiophene, polyparaphenylene, polyaniline, and derivatives thereof, and heterocyclic polymers such as polypyrrole and polythiophene, and derivatives thereof. Etc. can be used.

As the polymer used for the conductive material, a polymer compound having π conjugation in the molecular main chain and having predetermined conductivity is used. Examples of these include polyacene polymers, polythiophene, polyacetylene, polyparaphenylene, polyparaphenylenevinylene, polythiophenvinylene, polyaniline, polypyrrole, polythiophene, polyselenophene, poly (3-alkylthiophene), and polyisothianaphthene. Etc. can be used.

It is more preferable to use a carbon material such as graphite, carbon black or acetylene black as a conductive material in order to increase the conductivity of the electrode.

As an example of the current collector 1, a carbon plate, conductive rubber, or a metal plate or foil, which is not corroded by the electrolyte, may be appropriately selected and used.

An organic binder is used to secure the bonding force between the active material and the conductive material and to fix the electrode on the current collector 1. Examples of the type include thermoplastic resins such as polyester resin, polyamide resin, polyacrylate resin, polycarbonate resin, polyurethane resin, cellulose resin, polyolefin resin, polyvinyl resin, fluorine resin, and polyimide resin. Further, a compound (acrylate monomer or oligomer) into which a functional group is introduced may be mixed with these thermoplastic resins and used. Also, acrylates, oligomers alone, or mixed systems of oligomers and monomers can be used. Particularly preferred binders include polyvinylidene fluoride, styrene / butadiene copolymer, or hydrogenated styrene / butadiene copolymer.

As a method for preparing the mixture, an active material, a conductive material, and a binder appropriately selected from the above materials are mixed,
An organic solvent such as toluene, methyl ethyl ketone, N-methyl-2-pyrrolidone, N, N-dimethylformamide, or a mixture thereof is added thereto. And it prepares by mixing and dispersing using a disperser, such as a homogenizer, a ball mill, a sand mill, and a roll mill.

As the film forming method in the film forming step, the above-mentioned mixture is applied onto the current collector 1 by a general printing method such as dispenser, gravure, die head, screen printing, offset printing and the like. When a thick film is formed, it is preferable to pour the mixture into a frame provided on the current collector 1.

The jig used for dividing the electrodes may be a spatula having a V-shaped tip section, a roller, a needle, a nail, a wire, a net having a V-shaped tip section.
It can be a mesh, plate, or mold with a specific pattern. The electrode is divided into a plurality of parts by pressing or rubbing these jigs against the electrode.

FIG. 1 is a view for explaining a PDAAAQ electrode 2a manufactured in a first embodiment of a method for manufacturing a battery electrode according to the present invention, and FIG.
FIG. 2B is a schematic view of a cross-sectional structure of the PDAAQ electrode 2a, and FIG. 2C is a microstructure view of a cross-section of the PDAAQ electrode 2a. The divided portion is formed by removing part or all of the coating film after film formation. In particular, it is most preferable that the current collector 1 is exposed and the electrodes are completely divided.

Further, the electrode mixture obtained by film formation and division is dried to obtain an electrode. Examples of the heat source in the drying step include hot air, infrared rays, microwaves, high frequency waves and the like, and combinations thereof.

A method for forming a film by subdividing an electrode using a mask has been widely known and practiced. However, in this manufacturing method, as shown in FIG. 7B, when the film thickness of the electrode increases, the electrode 2f is lifted together with the mask 3 in the mask removing step, and the electrode 2f is separated from the current collector 1. Japanese Patent Application Laid-Open No. Hei 10-223209 discloses a method of dividing an electrode in order to obtain a non-coated portion for terminal attachment. However, the splitting of the electrodes is after the electrodes have dried.

In each of the embodiments according to the present invention, the electrode is divided after the film is formed, and then the electrode is dried to prevent the electrode from cracking or peeling off from the current collector 1, and to reduce the thickness and the thickness of the electrode. The method is characterized by facilitating an increase in area, and is completely different in purpose, configuration, and effect from the above-described conventionally known methods.

The phenomenon that occurs when the formed electrode is dried will be described in detail below. The polymer in the mixture is swollen or dissolved by taking in the solvent. During drying, the solvent evaporates and the electrode shrinks violently. On the other hand, the current collector 1 does not change in volume before and after the electrode is dried. Therefore, due to the difference in volume change between the two, distortion occurs inside the electrode during drying. As the area and / or thickness of the electrode increases, this strain increases and the electrode and the current collector 1
Peeling and cracks of the electrode (indicated by zigzag lines in FIG. 2A) occur.

FIG. 2 is a view for explaining an integrated PDAAQ electrode 2b manufactured by the first comparative example of the conventional method, and FIG. 2A schematically shows the distortion when the PDAAQ electrode 2b is dried. (B) is a PDA.
FIG. 5 is a diagram schematically illustrating a state where the strain of the AQ electrode 2a is dispersed. The reason why the electrode cracks will be described with reference to the drawings. For the above reasons, the electrodes tend to shrink when dry. Then, distortion occurs in the direction indicated by the arrow 向 か う toward the four corners in FIG. As the area of the electrode increases, this strain increases, causing cracking. When the electrode is divided by the battery electrode manufacturing method of the present invention, as shown in FIG. 2 (b), the strain is distributed to each divided portion of the electrode and becomes smaller. As a result, cracking of the electrode can be prevented.

Next, the reason why the peeling of the electrode occurs is as follows.
This will be described with reference to the drawings. FIGS. 3A and 3B are views for explaining a PDAAQ electrode having an integral structure manufactured by applying the present invention to the first comparative example of the conventional method. FIGS.
It is a figure which shows typically the mode of peeling from the collector 1 by the distortion at the time of drying in the AQ electrodes 2a and 2b, and the figure (c) which applies this invention to the PDAAQ electrode 2a, and FIG. 3 is a cross-sectional view schematically showing a state in which strain and peeling from a current collector 1 are suppressed. As shown in FIG. 3A, since the lower part of the electrode is in close contact with the current collector 1, the shrinkage during drying is small. On the other hand, there is no restriction on the current collector 1 at the upper part of the electrode, and therefore, the electrode largely contracts. As the thickness of the electrode increases, the difference in shrinkage between the lower part and the upper part of the electrode increases, causing distortion inside the electrode. As shown in FIG. 3 (b), the electrode curves to relieve this distortion. For this reason, as the film thickness increases, both the distortion and the curvature increase, and the peeling of the electrode tends to occur. When the electrode is divided by the method for producing an electrode for a battery according to the present invention, as shown in FIG. 3 (c), the strain inside the electrode is distributed to each divided portion and becomes small, so that the separation of the electrode can be prevented.

As described above, by dividing the electrode by the method for manufacturing a battery electrode according to the present invention, it is possible to prevent the electrode from cracking due to an increase in the area or from the current collector 1 due to an increase in the film thickness.

The production method of the first embodiment will be described in more detail. As the current collector 1, a carbon plate (for example, size: 70)
× 70 × 0.6 mm), poly-1,5-diaminoanthraquinone (hereinafter, PDAAQ) as an active material, vapor grown carbon fiber (hereinafter, VGCF) as a conductive material, polyvinylidene fluoride (hereinafter, PVD) as a binder
F) was used. PDAAQ: VGCF: PVDF = 4
The mixture was mixed at a weight ratio of 6: 46: 8, and N, N-dimethylformamide (hereinafter, DMF) was added to prepare a paste of an electrode mixture. This paste was sufficiently stirred, a 50 mm × 50 mm mask was placed on a carbon plate, and the paste was poured to form a film. After the film formation, the mask was removed, and the electrode was divided according to the pattern shown in FIG. 1A using a spatula having a V-shaped cross section at the tip. The size of the divided electrodes is about 10 × 10 mm. The spatula used was made of polyethylene, the width of the spatula was 1 mm, the thickness was about 500 μm, and the angle of the tip was about 45 degrees. Then, the electrode is heated to 120 ° C.
And dried in a hot air circulating furnace to remove DMF.

The thickness of the mask is from about 200 μm to about 140
Up to 0 μm, about 200 μm was prepared, and 100 electrodes were prepared for each thickness of the mask. With drying, the thickness of the electrode shrunk to about half, and the thickness of the electrode after drying was about 100 to 700 μm. The prepared electrode was visually inspected for cracks or peeling, and was discriminated into a good product and a defective product. FIG. 8 shows the yield for each film thickness of the electrode manufactured in the first embodiment. Further, the maximum film thickness that can secure a yield of 80% or more is defined as the maximum film thickness in the present manufacturing method. As a result, when a 1200 μm mask is used, the first
The maximum film thickness in the embodiment was about 600 μm. According to the manufacturing method of the first embodiment, a thick electrode having the same area as the comparative example could be manufactured.

FIG. 9 is a diagram showing a comparison between the discharge characteristics of the PDAAQ electrode 2a manufactured according to the first embodiment of the present invention and the PDAAQ electrodes 2b and 2f manufactured according to the first and second comparative examples of the conventional method. Using a non-defective product having the maximum film thickness (measured film thickness: about 603 μm), discharge characteristics were examined. FIG. 9 shows the result. The measurement was carried out in a glass beaker of about 500 ml, the electrolyte was about 40% sulfuric acid, the counter electrode was the same shape as the current collector 1, a carbon plate of the same material, and the reference electrode was Ag / AgCl.
Using a (silver / silver chloride) electrode, the charge / discharge rate is about 1 mA
cm- ² . The electrode of the first embodiment is about 0.55 mAh · cm ⁻² , which is four times as large as the electrode manufactured by the conventional method.
Was obtained.

As described above, according to the first embodiment, by dividing the electrode after film formation, strain due to volume shrinkage during drying can be dispersed, and cracking or peeling can be prevented. Therefore, as a result of increasing the electrode area and thickness, when this electrode is used as a battery electrode,
First, since the electrode area can be increased, the trouble of combining and integrating small electrodes can be omitted, and as a result, the size of the battery can be easily increased. Also the second
In addition, since the electrode thickness can be increased, the volume and weight of the electrode can be increased, and as a result, the capacity of the battery can be increased. Third, even when the film thickness is the same, the electrode structure retains more force than the electrode having a single structure, so there is no embrittlement or relaxation during use and stable operation for a long period of time is possible. This has the effect of becoming

(Second Embodiment) An electrode mixture was prepared using the same active material, conductive material and binder as in the first embodiment, and a film was formed by the same method. After film formation, the mold was pressed to divide the electrodes. FIG. 4 is a schematic diagram of the PDAAQ electrode 2c after the division. The diameter of the divided electrode is about 10 mm.
The mold used is made of stainless steel, and the tip is thin to avoid peeling of the electrode during pressing. Thereafter, the electrode was dried with a hot air dryer at about 120 ° C. to remove DMF.

FIG. 8 shows each film thickness of the PDAAQ electrode 2c manufactured according to the second embodiment of the present invention and the first and second conventional methods.
FIG. 9 is a diagram showing the yield with respect to each film thickness of PDAAQ electrodes 2b and 2f manufactured by Comparative Example 2. By changing the mask thickness in the same manner as in the first embodiment, 100 electrodes were manufactured for each film thickness. As shown in FIG. 8, the maximum film thickness of the second embodiment was about 500 μm. It has been found that a thick electrode can be obtained by the manufacturing method of the second embodiment, similarly to the first embodiment.

FIG. 9 is a diagram showing a comparison between the discharge characteristics of the PDAAQ electrode 2c manufactured according to the second embodiment of the present invention and the PDAAQ electrodes 2b and 2f manufactured according to the first and second comparative examples of the conventional method. FIG. 9 shows the discharge characteristics of a non-defective product having a maximum film thickness (measured film thickness: about 495 μm) manufactured in the second embodiment.
Are shown together. The configuration and the discharge rate of the battery cell are the same as in the first embodiment. Also in the second embodiment, the discharge capacity was increased as compared with the comparative example, and the effect of increasing the thickness of the electrode by this manufacturing method was confirmed.

(Third Embodiment) FIG. 5 shows a PDAAQ manufactured in a third embodiment of the method for manufacturing a battery electrode according to the present invention.
FIGS. 4A and 4B are diagrams for explaining the electrodes 2d and 2e, wherein FIG. 4A is a schematic view of the PDAAAQ electrodes 2d and 2e as viewed from a cross section, and FIG. It is a figure which shows a structure typically. Also in the third embodiment, the same current collector 1 and electrode mixture as those in the first and second embodiments were used. The film forming method, the division pattern, the electrode division method, and the drying method are exactly the same as in the first embodiment.
After the drying, as shown in FIGS. 5A and 5B, the electrode mixture 2e having the same composition was embedded in the divided portions of the electrodes to integrate the electrodes. Thereafter, the electrode mixture was dried again at about 120 ° C., but the embedded electrode mixture did not crack or peel during drying.

FIG. 8 shows the respective thicknesses of the PDAAQ electrodes 2d and 2e manufactured according to the third embodiment of the present invention and the PDAAQ electrodes 2b and 2 manufactured according to the first and second comparative examples of the conventional method.
It is a figure which shows the yield for each film thickness of f. FIG. 8 shows the yield with respect to the film thickness as in the first and second embodiments. The maximum thickness of the third embodiment was about 600 μm.
According to the manufacturing method of the third embodiment, the same yield as that of the first embodiment was obtained, and a smooth electrode was manufactured.

FIG. 9 shows PDAAQ electrodes 2d and 2e manufactured according to the third embodiment of the present invention and first and second conventional methods.
FIG. 9 is a diagram showing a comparison of discharge characteristics of PDAAQ electrodes 2b and 2f manufactured according to a comparative example. FIG. 9 shows the discharge characteristics of a non-defective product having the maximum film thickness (measured film thickness: about 598 μm) manufactured in the third embodiment. All measurement conditions are the same as in the first and second embodiments. By filling the electrode mixture again in the divided portion, the amount of the active material was increased, and the capacity was further increased as compared with the first and second embodiments.

(First Comparative Example) FIG. 6 is a schematic view of an integrated PDAAQ electrode 2b manufactured from the first comparative example of the conventional method as viewed from above. The exactly same electrode mixture and current collector 1 as in the first to third embodiments were used. In the first comparative example, FIG.
As shown in Fig. 7, after the integrated electrode was manufactured, no division was performed. Thereafter, the electrode was dried at 120 ° C. First
As in the third to third embodiments, electrodes having different thicknesses were manufactured by changing the thickness of the mask. However, as shown in FIG. 8, the maximum thickness in the first comparative example was only about 100 μm. The thickness of the mask used at this time is about 200 μm. A non-defective product having the maximum film thickness (measured film thickness:
As shown in FIG. 9, the discharge capacity of about 108 μm) is about 0.1 μm.
It was 14 mAh · cm ⁻² . First to third measurement
As in the embodiment, good electrodes were used, but floating from the current collector 1 was observed during the measurement. The electrode manufactured in the first comparative example is considered to have poor adhesion to the current collector 1.

(Second Comparative Example) FIG. 7 is a view for explaining a second comparative example of the conventional method. FIG. 7A shows the structure of the mask 3 used in the second comparative example of the conventional method. It is a figure which shows typically, and the figure (b) is a 2nd comparative example of a conventional method,
FIG. 4 is a diagram schematically illustrating a state in which an electrode is lifted and removed from a current collector 1 when a mask 3 is removed after film formation. The same electrode mixture and current collector 1 as in the first to third embodiments and the first comparative example were used. As shown in FIG. 7A, a film was formed in a state where the electrodes were divided using a mask 3 having a division pattern in advance, and then dried at 120 ° C.

FIG. 8 shows the respective film thicknesses of the PDAAQ electrodes 2a, 2c, 2d, and 2e manufactured according to the first to third embodiments of the present invention, and the P-type manufactured according to the first and second comparative examples of the conventional method.
It is a figure which shows the yield for each film thickness of DAAQ electrode 2b, 2f. The horizontal axis is the average thickness of the electrode (unit is [μ
m]) and the vertical axis is the yield (unit is [%]). First
The yield with respect to the PDAAQ electrode 2a manufactured according to the embodiment is indicated by ●, and the PDA manufactured according to the second embodiment
The yield for the AQ electrode 2c is indicated by ■, the yield for the PDAAQ electrodes 2d and 2e manufactured according to the third embodiment is indicated by で, and the PDAA manufactured according to the first comparative example.
The yield for the Q electrode 2b is indicated by x, and the yield for the PDAAQ electrode 2f manufactured in the second comparative example is ◆.
Indicated by

In the same manner as in the first to third embodiments and the first comparative example, 100 electrodes of each thickness were produced by the production method of the second comparative example. In the second comparative example, FIG.
As shown in (b), when the mask 3 was removed, the electrode was lifted together with the mask 3 and peeled off from the current collector 1, so that it was difficult to increase the film thickness. As shown in FIG. 8, the maximum thickness of the second comparative example was about 200 μm.

FIG. 9 shows PDAAQ electrodes 2a, 2c and 2d manufactured according to the first to third embodiments of the present invention, and PDAAQ electrodes 2 manufactured according to the first and second comparative examples of the conventional method.
It is a figure which shows and compares discharge characteristics of b and 2f. The horizontal axis represents the discharge capacity (unit: [mAh · cm ⁻² ]), and the vertical axis represents the output voltage (unit: [mV]). As shown in FIG. 9, the discharge capacity of the non-defective product having the maximum film thickness (actually measured film thickness: 201 μm) manufactured by the second comparative example was about 0.22 mAh · cm ⁻² . This is about 1 / compared to the first to third embodiments.
It was only 2/3.

Here, the above-described Japanese Utility Model Laid-Open Publication No. 6-70162 (third prior art) and the above embodiments will be compared. First
Focusing on the object of the invention, the third prior art mentions prevention of deterioration of the power generation performance of the solid electrolyte fuel cell and prevention of cracking of the power generation film, but the object of the present invention is to increase the electrode film thickness in the secondary battery. The purpose is different in that the ratio of the electrode to the entire battery is increased, and the size of the electrode is increased to facilitate the size of the battery. Second, focusing on the configuration of the invention, in the third conventional technique, the electrode is formed on the solid electrolyte layer (ion conductor), whereas the electrode of the invention is the current collector 1 (electron conductor). The configuration differs greatly in that it is formed above. Further, in the third prior art, there is no description about the division of the electrodes, and it is completely unknown whether the film is to be formed in a state of being divided from the beginning or to be divided after the film is formed. On the other hand, in the present invention, the electrode after film formation is divided into a plurality of portions, and this is dried, whereby a specific effect can be exhibited. Thirdly, focusing on the operation and effect of the invention, in the third prior art, since the thermal expansion coefficients of the solid electrolyte layer and the electrode layer are different, firing,
Alternatively, it is described that cracking and peeling of the electrode are easily caused by a temperature change during operation, and the power generation performance is deteriorated.
However, it is completely unknown what process leads to cracking and peeling of the electrode. On the other hand, in the present invention, it is explained that the cracking and peeling of the electrode is caused by a volume change (shrinkage) accompanying the evaporation of the solvent when the electrode is dried, and the process leading to the cracking and peeling is described in detail. The operation and effect are different in that it is stated that the problem can be solved by providing the above configuration. That is, as described above, the present invention and Japanese Utility Model Laid-Open Publication No. 6-70162 differ from each other in the purpose, configuration, operation, and effect.

It should be noted that the present invention is not limited to the above embodiments, and each embodiment can be appropriately modified within the scope of the technical idea of the present invention. Further, the number, position, shape, and the like of the constituent members are not limited to the above-described embodiment,
The number, position, shape, and the like suitable for carrying out the present invention can be obtained. In each drawing, the same components are denoted by the same reference numerals.

[0042]

According to the present invention, by dividing the electrode after film formation, the strain accompanying the volume shrinkage at the time of drying can be dispersed, and cracking or peeling can be prevented. Therefore, the electrode area and thickness can be increased. As a result, when this electrode is used as a battery electrode, firstly, it is possible to increase the electrode area, thereby combining small electrodes and integrating them. This saves time and, as a result, facilitates upsizing of the battery. Second, since the electrode thickness can be increased, the volume and weight of the electrode can be increased, and as a result, the capacity of the battery can be increased. Also the third
In addition, even if the film thickness is the same, since the holding force of the electrode structure is improved as compared with the electrode having a single structure, there is no embrittlement or relaxation during use, and stable operation can be performed for a long time. It works.

[Brief description of the drawings]

FIG. 1 is a method for manufacturing a battery electrode according to the present invention, and a PDA manufactured in the first embodiment of a battery electrode and a secondary battery.
It is a figure for demonstrating an AQ electrode, and the same figure (a) is P
FIG. 2B is a top view of the DAAAQ electrode, and FIG. 2B is a schematic view of a cross-sectional structure of the PDAAQ electrode, and FIG.

FIG. 2 is a view for explaining a PDAAAQ electrode having an integral structure manufactured according to a first comparative example of a conventional method, and FIG. 2A is a view schematically showing a strain when the PDAAQ electrode is dried. FIG. 2B is a diagram schematically showing a state in which the strain of the PDAAQ electrode is dispersed.

FIGS. 3A and 3B are diagrams for explaining a PDAAAQ electrode having an integral structure manufactured by applying the present invention to a first comparative example of a conventional method. FIGS.
It is a figure which shows typically the mode of the peeling from the current collector 1 by the distortion at the time of drying, and the figure (c) which applied this invention to the PDAAQ electrode, and shows the distortion at the time of drying and the current collector 1 It is sectional drawing which shows the mode that peeling was suppressed typically.

FIG. 4 is a PDA manufactured by the method of the second embodiment of the present invention.
It is the schematic diagram which looked at the AQ electrode from the upper part.

FIG. 5 is a diagram illustrating a method for manufacturing a battery electrode according to the present invention, and a PDA manufactured in a third embodiment of a battery electrode and a secondary battery.
It is a figure for demonstrating an AQ electrode, and the same figure (a) is P
FIG. 3B is a schematic view of the DAAQ electrode viewed from a cross section, and FIG.
FIG. 3 is a diagram schematically showing a fine structure of a cross section of a PDAAAQ electrode.

FIG. 6 is a schematic diagram of a PDAAAQ electrode having an integral structure manufactured according to a first comparative example of a conventional method, as viewed from above.

FIG. 7 is a diagram for explaining a second comparative example of the conventional method, and FIG. 7A is a diagram schematically showing the structure of a mask used in the second comparative example of the conventional method. FIG. 2B is a view schematically showing a state in which the electrode is lifted up and removed from the current collector when removing the mask after film formation in the second comparative example of the conventional method.

FIG. 8 is a diagram showing the yield for each film thickness of the PDAAQ electrode manufactured according to the first to third embodiments of the present invention and the film thickness of the PDAAQ electrode manufactured according to the first and second comparative examples of the conventional method.

FIG. 9 is a diagram showing a comparison of the discharge characteristics of the PDAAQ electrodes manufactured according to the first to third embodiments of the present invention and the PDAAQ electrodes manufactured according to the first and second comparative examples of the conventional method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Current collector 2a ... PDAA manufactured by 1st Embodiment of this invention
Q electrode 2b: PDAAA having an integral structure manufactured according to the first comparative example of the conventional method Qc 2c: PDAA manufactured according to the second embodiment of the present invention
Q electrode 2d: PDAA fabricated according to the third embodiment of the present invention
Q electrode (PDAAQ electrode after division) 2e: PDAA manufactured according to the third embodiment of the present invention
Q electrode (PDAAQ electrode formed second time) 2f ... PDAAQ electrode formed in second comparative example of conventional method 3 ... Mask used for film formation in second comparative example of conventional method

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaki Fujiwara 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation (72) Inventor Toshihiko Nishiyama 5-7-1 Shiba, Minato-ku, Tokyo NEC (56) References JP-A-59-49161 (JP, A) JP-A-7-296792 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01M 4/02 -4/04 H01M 4/60 H01M 4/62 H01M 10/40

Claims (7)

(57) [Claims] 1. A method for manufacturing an electrode for a battery, wherein the capacity per unit area is increased and the ratio of the electrode to the entire battery is increased, and the size of the battery is easily increased. A film forming step of forming an electrode by forming a film on the current collector, a dividing step of dividing the formed electrode into a plurality of predetermined portions, and a predetermined process of dividing the electrode divided into the plurality of portions into predetermined portions. A drying step of drying in a temperature atmosphere , wherein the polymer used for the active material absorbs and desorbs protons.
Doping and elimination of ions other than protons and / or protons
A method for producing an electrode for a battery , comprising a polymer compound that causes an oxidation-reduction reaction accompanying doping . 2. A method for manufacturing an electrode for a battery, wherein the capacity per unit area is increased and the ratio of the electrode to the entire battery is increased, and the size of the battery is easily increased. A film forming step of forming an electrode by forming a film on the current collector, a dividing step of dividing the formed electrode into a plurality of predetermined portions, and a predetermined process of dividing the electrode divided into the plurality of portions into predetermined portions. A drying step of drying in a temperature atmosphere , wherein the polymer used for the conductive material has π conjugation in the molecular main chain.
A method for producing an electrode for a battery , comprising a polymer compound having predetermined conductivity . 3. The method according to claim 1, wherein the film forming step includes a step of applying the electrode mixture on the current collector by a printing method. 4. An electrode structure for a battery, which increases the capacity per unit area and increases the ratio of the electrode to the entire battery, and facilitates upsizing of the battery, wherein the electrode assembly includes a polymer as an active material. The agent was formed on the current collector and the film was formed.
Has a post and the electrode is divided and then dried into a plurality partial electrodes, the polymer used in the active material, absorption and desorption of protons, and / or due to doping and undoping of other ions except proton redox reaction An electrode structure for a battery, comprising a polymer compound that produces the following. 5. An electrode structure for a battery, which increases the capacity per unit area and the ratio of the electrode to the entire battery, and facilitates upsizing of the battery, wherein the electrode assembly includes a polymer as a conductive material. Film is formed on the current collector, and the electrode after the film formation is divided into a plurality of portions.
An electrode structure for a battery, comprising a dried electrode, wherein the polymer used for the conductive material includes a polymer compound having π conjugation in a molecular main chain and having a predetermined conductivity. 6. A secondary battery having a battery electrode structure for increasing the capacity per unit area and increasing the ratio of the electrode to the whole battery to facilitate upsizing of the battery. The structure is such that an electrode mixture containing a polymer as an active material is formed on a current collector , and the electrode after the film formation is formed.
A polymer having an electrode which is divided into a plurality of portions and then dried , wherein the polymer used for the active material causes adsorption / desorption of protons and / or doping of other ions other than protons and redox reaction accompanying dedoping A secondary battery comprising a compound. 7. A secondary battery having a battery electrode structure that facilitates upsizing of a battery by increasing the capacity per unit area and increasing the ratio of the electrode to the entire battery, wherein the battery electrode is provided. The structure is such that an electrode mixture containing a polymer as a conductive material is formed on a current collector , and the electrode after the film formation is formed on the current collector.
A secondary battery having an electrode that is divided into a plurality of portions and then dried , wherein the polymer used for the conductive material includes a polymer compound having π conjugation in the molecular main chain and having a predetermined conductivity. .