Electrode manufacturing method and electrode manufacturing apparatus

Abstract

To provide an electrode manufacturing method that achieves both a high degree of design freedom, high quality, and high productivity.SOLUTION: An electrode manufacturing method includes a first step of applying an electrode liquid composition containing an electrode mixture to an arbitrary position on a substrate in an arbitrary shape, a second step of acquiring information indicating a position in which the electrode liquid composition containing the electrode mixture is applied, and a third step of cutting out only the substrate at an arbitrary position in a region excluding an electrode mixture region to which the electrode liquid composition containing the electrode mixture is applied, and cutting out the electrode in an arbitrary shape.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] This invention relates to an electrode manufacturing method and an electrode manufacturing apparatus. [Background technology]

[0002] Rechargeable secondary batteries have seen a rapid expansion in recent years, ranging from small consumer devices such as wearable devices and smartphones to large devices such as electric vehicles and stationary storage batteries. However, conventional battery electrode manufacturing methods make it difficult to flexibly switch between product types, thus creating a need for new manufacturing methods.

[0003] Conventionally, the positive and negative electrodes for secondary batteries are generally manufactured by mixing battery materials, mainly ceramics and carbon, with auxiliary components such as conductive additives and binders to create a coating liquid, and then applying this coating liquid to a metal substrate using a continuous (analog) coating method. For example, aluminum foil is used as the metal substrate. For example, die coating or gravure printing is used as the continuous (analog) coating method.

[0004] The positive and negative electrodes, coated with positive and negative electrode composite layers, are processed to the required size and shape and combined with an insulating sheet consisting of a separator or solid electrolyte to form the basic structure of the cell. Shaping is primarily done using a die-cutting method with a die such as a Thomson blade. Changing the battery shape requires redesigning the die-cutting mold, stopping the production line, and replacing the die-cutting mold. Furthermore, the more complex the edge shapes of the positive and negative electrodes, the greater the risk of quality degradation, such as chipping of the electrode composite layer during die-cutting.

[0005] On the other hand, in recent years, an electrode cutting technique using a laser has been proposed (see, for example, Patent Document 1). The cutting technique using a laser eliminates the need for re-design of the mold and changeover, and can reduce the costs associated with switching production varieties. In addition, the cutting technique using a laser has a high degree of design freedom and facilitates the production of batteries of arbitrary shapes according to the shape of the device. Therefore, by effectively using the limited space, a battery system with a high energy density can be provided.

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when attempting to cut the electrode including the region where the electrode composite material layer is coated with a laser, there is a concern that damage due to the influence of heat is applied to the periphery of the electrode cutting portion, resulting in a decrease in battery performance. In addition, compared to cutting only a metal foil of about 5 μm to 20 μm used for the base material, in order to cut the electrode composite material layer simultaneously, measures such as slowing down the laser scan speed or increasing the number of scans are required. Therefore, the processing time using a laser becomes longer, which causes a decrease in productivity and an increase in costs. Thus, conventionally, an electrode manufacturing method with a high degree of design freedom, high quality, and high productivity has not been established.

[0007] The present invention has been made in view of the above, and an object thereof is to provide an electrode manufacturing method that achieves both a high degree of design freedom, high quality, and high productivity.

Means for Solving the Problems

[0008] This electrode manufacturing method includes a first step of applying an electrode liquid composition containing an electrode composite material at an arbitrary position on a base material in an arbitrary shape, a second step of acquiring position information of the position where the electrode liquid composition containing the electrode composite material is applied, and a third step of cutting only the base material at an arbitrary position in a region excluding the electrode composite material region where the electrode liquid composition containing the electrode composite material is applied, and cutting out an electrode in an arbitrary shape. Furthermore, in the second step, the position information is obtained by image recognition of a mark formed by printing the electrode liquid composition containing the electrode mixture in an area excluding the electrode mixture area. .

Effects of the Invention

[0009] According to the disclosed technology, an electrode manufacturing method that can achieve both high design freedom and high quality and high productivity can be provided.

Brief Description of the Drawings

[0010] [Figure 1] It is a plan view illustrating an electrode according to the first embodiment. [Figure 2] It is a cross-sectional view illustrating an electrode according to the first embodiment. [Figure 3] It is a diagram (part 1) illustrating an electrode manufacturing method according to the first embodiment. [Figure 4] It is a diagram (part 2) illustrating an electrode manufacturing method according to the first embodiment. [Figure 5] It is a diagram (part 3) illustrating an electrode manufacturing method according to the first embodiment. [Figure 6] It is a diagram (part 4) illustrating an electrode manufacturing method according to the first embodiment. [Figure 7] It is a plan view illustrating an electrode according to the second embodiment. [Figure 8] It is a cross-sectional view illustrating an electrode according to the second embodiment. [Figure 9] It is a diagram (part 1) illustrating an electrode manufacturing method according to the second embodiment. [Figure 10] It is a diagram (part 2) illustrating an electrode manufacturing method according to the second embodiment. [Figure 11] It is a plan view illustrating an electrode according to a modification of the second embodiment. [Figure 12] It is a cross-sectional view illustrating an electrode according to a modification of the second embodiment. [Figure 13] It is a cross-sectional view illustrating an electrode according to the third embodiment. [Figure 14] It is a diagram illustrating an electrode manufacturing method according to the third embodiment. [Figure 15] It is a cross-sectional view illustrating an electrode according to a modification of the third embodiment. [Figure 16] It is a diagram illustrating an electrode manufacturing method according to a modification of the third embodiment. [Figure 17] This is a schematic diagram (part 1) illustrating an electrode manufacturing apparatus. [Figure 18] This is an example of a block diagram of the main hardware components of a control system. [Figure 19] This is an example of a block diagram of the main functions of a control system. [Figure 20] This is a schematic diagram (part 2) illustrating an electrode manufacturing apparatus. [Modes for carrying out the invention]

[0011] The embodiments for carrying out the invention will be described below with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0012] <First Embodiment> [Electrode structure] Figure 1 is a plan view illustrating an electrode according to the first embodiment. Figure 2 is a cross-sectional view illustrating an electrode according to the first embodiment, showing a cross-section along line AA in Figure 1.

[0013] As shown in Figures 1 and 2, the electrode 10 comprises a base material 11 and an electrode composite layer 12 formed on one surface 11a of the base material 11. The electrode 10 can be used in electrochemical elements such as primary batteries, secondary batteries, or capacitors, but is particularly suitable for use in lithium-ion secondary batteries. In the electrode 10, the thickness of the base material 11 is, for example, about 5 μm to 20 μm, and the thickness of the electrode composite layer 12 is, for example, about several tens of μm to 100 μm. Note that the planar shape of the base material 11 and the electrode composite layer 12 (shape viewed from the normal direction of one surface 11a of the base material 11) is just an example and is not limited to the shape shown in Figure 1.

[0014] On one surface 11a of the substrate 11, the uncoated portion 11m is provided in an annular shape outside the outer peripheral portion 12p of the electrode composite layer 12 in a plan view. The uncoated portion 11m is the part of the substrate 11 where one surface 11a is exposed and not covered by the electrode composite layer 12. The area shown by the low-density dot pattern in Figure 1 is the uncoated portion 11m.

[0015] The uncoated portion is not necessarily located outside the outer peripheral portion 12p of the electrode composite layer 12. For example, through holes may be formed that penetrate the substrate 11 and the electrode composite layer 12, in which case, The uncoated portion is also formed in an annular shape on the inner side of the inner circumference of the electrode composite layer 12 in a plan view (i.e., around the through hole provided in the base material 11).

[0016] In Figures 1 and 2, the X direction is the longitudinal direction of the electrode 10, the Y direction is the short direction of the electrode 10, and the Z direction is the thickness direction of the electrode 10. The X, Y, and Z directions are mutually orthogonal.

[0017] [Method for manufacturing electrodes] Next, a method for manufacturing an electrode according to the first embodiment will be described. The electrode composite layer 12 can be formed on the substrate 11 by a coating process that applies a printing process, using an electrode liquid composition, which is the material for forming the electrode composite layer 12. As the printing process, it is preferable to use a printing method that can apply the electrode liquid composition at any position and in any shape using digital data, and inkjet printing is particularly preferable because it can directly print digital images. Here, digital data refers to information about numbers or quantities, for example, the amount, shape, or position of application of the electrode liquid composition containing the electrode composite, expressed as a series of numerical values.

[0018] In the following, the electrode manufacturing method according to the first embodiment will be described using the case of inkjet printing as an example.

[0019] (Step of applying an electrode liquid composition containing electrode material onto a substrate) Figure 3 is an illustrative diagram (part 1) of the electrode manufacturing method according to the first embodiment, schematically showing the step of applying an electrode liquid composition containing electrode composite material onto a substrate.

[0020] In Figure 3, the electrode manufacturing apparatus 100 includes an inkjet head 101A, an image sensor 102A, and a conveyor belt 103. The electrode manufacturing apparatus 100 may also have multiple inkjet heads and multiple image sensors.

[0021] The inkjet head 101A is a line head that ejects an electrode liquid composition, such as ink, containing an electrode mixture 12A onto the substrate 11. The inkjet head 101A is equipped with a plurality of nozzles arranged perpendicular to the transport direction. The inkjet head 101A can apply the electrode liquid composition containing the electrode mixture 12A to any position on the substrate 11 in any shape.

[0022] The image sensor 102A acquires positional information for which the electrode liquid composition containing the electrode mixture 12A should be applied. The image sensor 102A is, for example, a CCD (Charge Coupled Device), a CMD (Cold Metal Detector), or a CMOS (Complementary Metal Oxide Semiconductor) sensor. The image sensor 102A can be appropriately selected from among these according to the required reading accuracy and speed.

[0023] The conveyor belt 103 is, for example, an endless belt stretched between two rollers and circulating. Here, the conveying direction of the conveyor belt 103 (sub-scanning direction) is defined as the Y direction, and the direction perpendicular to the conveying direction (main scanning direction) is defined as the X direction. These directions coincide with the X and Y directions in Figures 1 and 2.

[0024] Before applying the electrode liquid composition containing the electrode mixture 12A onto the substrate 11, the electrode manufacturing apparatus 100 determines the positions on the substrate 11 where the electrode liquid composition containing the electrode mixture 12A should be applied, based on information obtained from the image sensor 102A. For example, the image sensor 102A reads the distance from the edge 11e of the substrate 11 along the width direction (X direction) of the substrate 11, and calculates the application interval of the electrode liquid composition containing the electrode mixture 12A according to the speed at which the substrate 11 is transported along the transport direction Y.

[0025] As shown in Figure 3, for example, a long substrate 11 is placed on a conveyor belt 103. As the conveyor belt 103 transports the substrate 11 along the transport direction Y, the inkjet head 101A discharges an electrode liquid composition containing electrode material 12A from a nozzle. This coats the substrate 11 with an electrode liquid composition containing electrode material 12A of a predetermined shape. After being applied to the substrate 11, the electrode liquid composition containing electrode material 12A is dried in a drying process to form an electrode liquid layer 12.

[0026] By using a method that allows direct printing of digital images, such as inkjet printing, the electrode liquid composition containing the electrode mixture 12A can be applied to the substrate 11 at any position and in any shape based on a digital source. The digital data can be created using commercially available drawing software such as Adobe Illustrator.

[0027] (Step to acquire positional information of the electrode liquid composition containing the electrode mixture that has been applied) Figures 4 and 5 are diagrams (2) and (3) illustrating the electrode manufacturing method according to the first embodiment, and schematically show the step of acquiring positional information of the electrode composite layer 12 (i.e., positional information of the electrode liquid composition including the coated electrode composite 12A).

[0028] The positional information of the electrode composite layer 12 can be obtained, for example, by image recognition. Alternatively, the positional information of the electrode composite layer 12 may be obtained by irradiating the substrate 11 and the electrode composite layer 12 with light, receiving the reflected light, and detecting the step difference that occurs between the substrate 11 and the electrode composite layer 12. The method using image recognition is preferable because it is less affected by disturbances such as vibrations of the conveyor belt 103 and can obtain the positional information of the electrode composite layer 12 with high accuracy. The following will describe an example of obtaining the positional information of the electrode composite layer 12 by image recognition.

[0029] As shown in Figure 4, the positional information of the electrode composite layer 12 can be obtained using the image sensor 102B. Specifically, the image sensor 102B can obtain the positional information of the electrode composite layer 12 by, for example, image recognition of the edge shape 12e of the electrode composite region (the region where the electrode composite layer 12 is formed) to which the electrode liquid composition containing the electrode composite 12A is applied.

[0030] Furthermore, as shown in Figure 5, the image sensor 102B may acquire positional information of the electrode mixture layer 12 by image recognition of marks (alignment marks) formed in areas other than the electrode mixture region (the region where the electrode mixture layer 12 is formed) to which the electrode liquid composition containing the electrode mixture 12A is applied. Specifically, positional information of the electrode mixture layer 12 can be image-recognized using at least two alignment marks 300 placed near the electrode mixture layer 12. Note that one image sensor may be placed for each alignment mark.

[0031] Among these methods, the method of image recognition using alignment marks 300 is preferred because it does not require changing the image recognition algorithm depending on the shape of the electrode composite layer 12. The alignment marks 300 can be formed, for example, by inkjet printing or laser engraving.

[0032] When using inkjet printing, the alignment marks 300 can be formed by printing a colorant recognizable by the image sensor 102B onto the substrate 11, for example, in a cross shape. The colorant used to form the alignment marks 300 may be the same material as the material used to form the electrode composite layer 12, or a different material may be used, as long as it is an inkjet-dispensable colorant.

[0033] In this case, it is preferable to use the same material as the material used to form the electrode composite layer 12 as the colorant for the alignment marks 300. This allows the inkjet head and ink used to print the material for forming the alignment marks 300 to be the same as the inkjet head and ink used to print the material for forming the electrode composite layer 12, thereby simplifying the configuration of the printing system.

[0034] In addition to the printing described above, the alignment marks 300 may also be formed using a laser. For example, a laser may be used to form, for example, a cross-shaped through-hole in the substrate 11, and this through-hole may be used as the alignment marks 300.

[0035] (The process of cutting out electrodes) Figure 6 is an illustrative diagram (part 4) of the electrode manufacturing method according to the first embodiment, schematically showing the process of cutting out an electrode in an arbitrary shape.

[0036] After recognizing the positional information of the electrode mixture layer 12 (i.e., the positional information of the electrode liquid composition including the applied electrode mixture 12A) using image recognition, only the substrate 11 is cut at an arbitrary position in the region excluding the electrode mixture region to which the electrode liquid composition including the electrode mixture 12A is applied. For example, as shown in Figure 6, only the substrate 11 is cut at an arbitrary position 11c outside the electrode mixture layer 12 of the substrate 11 (i.e., a region that is not the region to which the electrode liquid composition including the electrode mixture 12A is applied). This makes it possible to produce an electrode 10 of any shape (see Figures 1 and 2) from which the electrode liquid composition including the electrode mixture 12A has been cut out.

[0037] As a method for cutting only the substrate 11, a method in which the processing position can be arbitrarily specified by digital data is preferred, and it is more preferable to use laser light 104L emitted from the laser head 104. An attenuator for adjusting the laser power, a reflective mirror, a beam expander for adjusting the laser beam diameter, a galvanometer scanner for laser scanning, and a focusing lens may be provided between the laser head 104 and the substrate 11 as needed. As for the wavelength range of the laser light 104L, it is preferable to use a wavelength range from visible to ultraviolet, and the oscillation pulse width is preferably shorter than nanoseconds, and more preferably several tens of picoseconds, considering the thermal effects of the substrate 11.

[0038] (Effects of combining digital printing and digital processing technologies) As described above, by combining inkjet printing, a digital printing technology, and laser cutting, a digital processing technology, it becomes possible to efficiently manufacture electrode composite layers 12 of any shape by, for example, modifying the digital data that can be used in common with each technology. In other words, the electrode manufacturing apparatus 100 can control the arbitrary position where the electrode liquid composition containing the electrode composite is applied, the arbitrary shape of the electrode liquid composition containing the electrode composite, and the arbitrary position where the substrate is cut, all using digital data. This enables an electrode manufacturing method with a high degree of design freedom.

[0039] The cutting of electrodes by laser cutting is disclosed, for example, in Patent Document 1 (JP 2018-129222 A), Patent Document 2 (JP 6432990 A), Patent Document 3 (JP 2012-221912 A), and Patent Document 4 (JP 2018-37143 A). However, the techniques disclosed in these documents all involve cutting the electrode liquid composition, which includes the electrode composite material applied together with the substrate, by laser, for electrodes in which the electrode-forming material is intermittently coated or continuously coated.

[0040] These methods result in significant differences in the laser cutting efficiency of the electrode liquid composition, which includes the substrate and electrode composite material. Therefore, as disclosed in Patent Document 3, it becomes necessary to change the laser intensity depending on the change in the cutting area, and as disclosed in Patent Document 4, depending on the material of the electrode liquid composition, which includes the electrode composite material, it may not be able to absorb the laser energy. As a result, the process of manufacturing electrodes becomes complicated, such as requiring a step to print a laser light absorbing member.

[0041] Furthermore, the cutting speed of the electrode liquid composition containing the electrode composite material is significantly lower than that of the substrate, leading to a decrease in production efficiency in the electrode cutting process. Additionally, the thermal effects associated with laser cutting on the electrode liquid composition containing the electrode composite material cannot be ignored, as disclosed in Patent Document 1 (Japanese Patent Application Publication No. 2018-129222).

[0042] In the electrode manufacturing method according to the first embodiment, to address these issues, the electrode liquid composition containing the electrode composite material 12A is digitally printed in an arbitrary shape, allowing the substrate 11 to be laser-cut while avoiding the areas where the electrode liquid composition containing the electrode composite material 12A is applied. By cutting only the substrate 11 without cutting the electrode composite material layer 12 at all, the complexity of processes such as detailed design of the laser intensity in the electrode cutting process and the decrease in productivity can be suppressed, and an electrode of arbitrary shape with stable quality and no thermal effects of the electrode liquid composition containing the electrode composite material near the cut end can be obtained. In other words, the electrode manufacturing method according to the first embodiment can realize a high-quality and highly productive electrode manufacturing method.

[0043] In the electrode manufacturing method according to the first embodiment, since only the substrate 11 is cut with a laser while avoiding the electrode composite layer 12, an uncoated portion 11m is provided on one surface 11a of the substrate 11 located around the electrode composite region where the electrode composite layer 12 is formed, as shown in Figures 1 and 2. The length L of the uncoated portion 11m (see Figure 1) can be appropriately adjusted according to the oscillation pulse width in laser cutting, but is preferably 10 μm or more and 500 μm or less. If the length L is less than 10 μm, the electrode liquid composition containing the electrode composite that forms the electrode composite layer 12 will be affected by heat and deteriorate. If the length L is greater than 500 μm, the ratio of the area occupied by the electrode composite layer 12 to the area of ​​the substrate 11 will decrease, resulting in a decrease in the energy density of the battery.

[0044] The electrode 10 will be described in detail below.

[0045] (Base material 11) The substrate 11 can be any metal foil or insulating substrate. The form of the substrate 11 is not particularly limited and can be, for example, a sheet or a long strip. Examples of metal foils include copper foil, aluminum foil, stainless steel foil, or nickel foil. Examples of insulating substrates include glass, glass epoxy, polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), cellulose paper, or rubber.

[0046] (Electrode liquid composition containing electrode composite material 12A) The electrode liquid composition applied by inkjet printing comprises at least one of a positive electrode active material and a negative electrode active material. The electrode liquid composition applied by inkjet printing may further optionally contain one or more of a dispersion medium, a dispersant, a conductive additive, a binder, a non-aqueous electrolyte, a solid electrolyte, a gel electrolyte, or a monomer that becomes a gel electrolyte through a polymerization process.

[0047] (Cathode active material) The positive electrode active material may be used alone or as a mixture of two or more types. There are no particular restrictions on the positive electrode active material as long as it can reversibly intercept and release alkali metal ions; however, alkali metal-containing transition metal compounds can be used.

[0048] Examples of alkali metal-containing transition metal compounds include lithium-containing transition metal compounds such as composite oxides containing lithium and one or more elements selected from the group consisting of cobalt, manganese, nickel, chromium, iron, and vanadium.

[0049] Examples of lithium-containing transition metal compounds include lithium-containing transition metal oxides such as lithium cobaltate, lithium nickelate, or lithium manganeseate.

[0050] As alkali metal-containing transition metal compounds, polyanionic compounds having an XO4 tetrahedron (X=P,S,As,Mo,W, or Si, etc.) in their crystal structure can also be used. Among these, lithium-containing transition metal phosphate compounds such as lithium iron phosphate or lithium vanadium phosphate are preferred in terms of cycle characteristics. In particular, lithium vanadium phosphate has a high lithium diffusion coefficient and excellent power characteristics.

[0051] Furthermore, in terms of electronic conductivity, it is preferable that the polyanionic compound is composited with a conductive additive such as a carbon material that coats the surface.

[0052] Examples of sodium-containing transition metal compounds include NaMO2 type oxides, sodium chromate (NaCrO2), sodium ironate (NaFeO2), sodium nickelate (NaNiO2), sodium cobaltate (NaCoO2), sodium manganese (NaMnO2), or sodium vanadate (NaVO2). A portion of M may be substituted with a metal element other than M and Na, such as at least one selected from the group consisting of Cr, Ni, Fe, Co, Mn, V, Ti, and Al. Also, as a sodium-containing metal oxide, Na2F ePO4F, NaVPO4F, NaCoPO4, NaNiPO4, NaMnPO4, NaMn 1.5 Ni 0.5 O4, or Na2V2(PO4)3, etc. can also be used.

[0053] (Negative electrode active material) As the negative electrode active material, a material capable of occluding and desorbing a metal that alloys with an alkali metal ion such as Li ion or Na ion can be used. Examples of such materials include composite oxides of transition metals and Li, metal oxides, alloy-based materials, inorganic compounds such as transition metal sulfides, carbon materials, organic compounds, Li metal, and Na metal.

[0054] Examples of the composite oxides include LiMnO2, LiMn2O4, lithium titanate (Li4Ti5O 12 , Li2Ti3O7), lithium magnesium titanate (LiMg 1 / 2 Ti 3 / 2 O4), lithium cobalt titanate (LiCo 1 / 2 Ti 3 / 2 O4), lithium zinc titanate (LiZn 1 / 2 Ti 3 / 2 O4), lithium iron titanate (LiFeTiO4), lithium chromium titanate (LiCrTiO4), lithium strontium titanate (Li2SrTi6O 14 ), or lithium barium titanate (Li2BaTi6O 14 ), etc.

[0055] Examples of the sodium composite oxides include sodium titanate, such as Na2Ti3O7 or Na4Ti5O 12 , etc. A part of Ti or Na in sodium titanate may be substituted with other elements. Examples of such elements include at least one selected from the group consisting of Ni, Co, Mn, Fe, Al, and Cr.

[0056] Examples of the metal oxides include TiO2, Nb2TiO7, WO3, MoO2, MnO2, V2O5, SiO2, SiO, or SnO2, etc.

[0057] Examples of alloying materials include Al, Si, Sn, Ge, Pb, As, or Sb. Examples of transition metal sulfides include FeS or TiS. Examples of carbon materials include graphite, poorly graphitizable carbon, or easily graphitizable carbon. For inorganic compounds, compounds in which the transition metal of the above composite oxide is substituted with a different element may be used.

[0058] These negative electrode active materials may be used individually or in combination of two or more types.

[0059] (dispersion medium) The dispersion medium is not particularly limited as long as it can disperse the active material, but examples include aqueous dispersion media such as water, ethylene glycol, or propylene glycol, and organic dispersion media such as N-methyl-2-pyrrolidone, 2-pyrrolidone, cyclohexanone, ethyl lactate, butyl acetate, mesitylene, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, dibutyl ether, diethyl ether, di-tert-butyl ether, 2-n-butoxymethanol, 2-dimethylethanol, N,N-dimethylacetamide, anisole, diethoxyethane, n-hexane, heptane, octane, nonane, decane, or p-menthane. The dispersion medium may be used alone or in combination of two or more types.

[0060] (Conductive additive) The conductive additive may be compounded with the active material beforehand, or it may be added when preparing the dispersion.

[0061] As conductive additives, for example, conductive carbon black formed by the furnace method, acetylene method, or gasification method, as well as carbon materials such as carbon nanofibers, carbon nanotubes, graphene, or graphite particles can be used.

[0062] Other conductive additives besides carbon materials include, for example, metal particles such as aluminum, or metal fibers.

[0063] The mass ratio of the conductive additive to the active material is preferably 10% or less, and more preferably 8% or less. When the mass ratio of the conductive additive to the active material is 10% or less, the stability of the dispersion is improved.

[0064] (Dispersant) There are no particular limitations on the dispersant as long as it can improve the dispersibility of the active material, polymer particles, or conductive additive in the dispersion medium. Examples include polymer types such as polycarboxylic acid systems, naphthalene sulfonic acid formalin condensate systems, polyethylene glycol, polycarboxylic acid partial alkyl ester systems, polyether systems, and polyalkylene polyamine systems; surfactant types such as alkyl sulfonic acid systems, quaternary ammonium systems, higher alcohol alkylene oxide systems, polyhydric alcohol ester systems, and alkyl polyamine systems; and inorganic types such as polyphosphate systems.

[0065] (binder) A binder can be added when the bonding of positive electrode materials to each other, negative electrode materials to each other, or positive or negative electrode materials to the electrical conductive layer is insufficient with the dispersant or electrolyte material, thereby ensuring binding force. While there are no particular restrictions on the binder as long as it provides binding force, a compound that does not increase viscosity is preferable from the viewpoint of inkjet ejection performance. Binders can be prepared by polymerizing monomer compounds after inkjet printing, or by using polymer particles. Furthermore, as a material that does not increase the viscosity of the liquid composition, polymer compounds that can be dispersed in the dispersion medium can be used. In the case of using polymer compounds that can dissolve in the dispersion medium, the liquid composition in which the polymer compound is dissolved in the dispersion medium should have a viscosity that allows it to be ejected from the liquid ejection head.

[0066] Examples of using monomer compounds include a method of applying a dispersion containing a compound having polymerization sites and a polymerization initiator or catalyst, in which the compound having polymerization sites is dissolved, and then heating it, or a method of irradiating with non-ionizing radiation, ionizing radiation, or infrared radiation.

[0067] In compounds having polymerizable sites, the polymerization site may be a single site within the molecule, or it may be polyfunctional. A polyfunctional polymerizable compound means a compound having two or more polymerizable groups. There are no particular restrictions on polyfunctional polymerizable compounds as long as they can be polymerized by heating or irradiation with non-ionizing radiation, ionizing radiation, or infrared radiation. Examples of polyfunctional polymerizable compounds include acrylate resins, methacrylate resins, urethane acrylate resins, vinyl ester resins, unsaturated polyesters, epoxy resins, oxetane resins, vinyl ethers, or resins utilizing the en-thiol reaction. Among these, acrylate resins, methacrylate resins, urethane acrylate resins, or vinyl ester resins are preferred from the viewpoint of productivity.

[0068] Examples of materials that constitute polymer particles include polyvinylidene fluoride, acrylic resin, polyamide compounds, polyimide compounds, polyamide-imide, ethylene-propylene-butadiene rubber (EPBR), styrene-butadiene copolymer, nitrile butadiene rubber (HNBR), isoprene rubber, polyisobutene, polyethylene glycol (PEO), polymethyl methacrylic acid (PMMA), polyethylene vinyl acetate (PEVA), polyethylene, polypropylene, polyurethane, nylon, polytetrafluoroethylene, polyphenylene sulfide, polyethylene tephthalate, or polybutylene tephthalate.

[0069] Examples of polymer compounds include polyamide compounds, polyimide compounds, polyamide-imides, ethylene-propylene-butadiene rubber (EPBR), styrene-butadiene rubber (SBR), nitrile-butadiene rubber (NBR), isoprene rubber, polyisobutene, polyethylene glycol (PEO), polymethyl methacrylic acid (PMMA), or polyethylene vinyl acetate (PEVA).

[0070] The mass ratio of the binder to the active material is preferably 10% or less, and more preferably 5% or less. When the mass ratio of the binder to the active material is 10% or less, the binding force during electrode formation is improved without impairing the dispensing performance.

[0071] <Second Embodiment> In the second embodiment, an example of an electrode having an electronic insulating layer is shown. Figure 7 is a plan view illustrating an electrode according to the second embodiment. Figure 8 is a cross-sectional view illustrating an electrode according to the second embodiment, showing a cross-section along line BB in Figure 7.

[0072] As shown in Figures 7 and 8, electrode 20 differs from electrode 10 (see Figures 1 and 2) in that an electronic insulating layer 21 is formed on it. Preferably, the electronic insulating layer 21 covers the entire top and side surfaces of electrode composite layer 12, and there are no portions of electrode composite layer 12 exposed from the electronic insulating layer 21.

[0073] On one surface 11a of the substrate 11, the uncoated portion 11n is provided in an annular shape outside the outer peripheral portion 21p of the electronic insulating layer 21 in a plan view. The uncoated portion 11n is the part of the substrate 11 where one surface 11a is exposed and not covered by the electrode composite layer 12 or the electronic insulating layer 21. The uncoated portion 11n is shown by the low-density dot pattern in Figure 7.

[0074] (Layer coating of solid electrolytes or gel electrolytes, etc.) Figure 9 illustrates an electrode manufacturing method according to the second embodiment. As shown in Figure 4 or Figure 5, after acquiring positional information of the electrode composite layer 12 by image recognition, an electrolyte liquid composition 21A containing a solid electrolyte or gel electrolyte is inkjet printed onto the electrode composite layer 12 to form an electronic insulating layer 21, as shown in Figure 9. At this time, the electrolyte liquid composition 21A is applied so as to cover the entire electrode composite layer 12 (top and sides). When the electrolyte liquid composition 21A dries, it becomes an electronic insulating layer 21. Note that the electrolyte liquid composition 21A is an example of a liquid composition that does not contain an active material but contains an electronic insulating layer forming material. In this case, the electronic insulating layer forming material is a solid electrolyte or a gel electrolyte.

[0075] Furthermore, similar to the first embodiment, the substrate 11 is cut out at any position in the region where the electronic insulating layer 21 is not formed (the region where the electrolyte liquid composition 21A is not applied). As a result, as shown in Figures 7 and 8, exposure of the electrode composite layer 12 can be prevented in the electrode 20, and an electrode end structure can be obtained that can prevent short circuits inside the battery due to the sliding of active material, etc.

[0076] (Electrolyte liquid composition) As the electrolyte liquid composition 21A, for example, a liquid composition in which a solid electrolyte is dispersed in a dispersion medium can be used. The electrolyte liquid composition 21A may further contain, if necessary, a dispersant, a binder, or a monomer that becomes a polymer through a polymerization process. The average particle size of the solid electrolyte is preferably 10 μm or less, and more preferably 5 μm or less. When the average particle size of the solid electrolyte is 10 μm or less, the discharge stability and sedimentation resistance of the liquid composition are improved. The d10 of the solid electrolyte is preferably 0.1 μm or more. When the d10 of the solid electrolyte is 0.1 μm or more, the storage stability of the liquid composition is improved.

[0077] The electrolyte liquid composition of this embodiment may not contain a solid electrolyte, but may contain a gel electrolyte. As described above, the gel electrolyte contains a resin and a non-aqueous electrolyte, an ionic liquid, a grime, or an electrolyte salt. The viscosity of the liquid composition at 25°C is preferably in the range of 3 mPa·s to 100 mPa·s. More preferably, it is between 9 mPa·s and 50 mPa·s.

[0078] (Solid electrolyte or gel electrolyte) (Ceramic solid electrolyte for lithium-ion secondary batteries) As electrolytes, solid electrolytes made of ceramics such as oxides or sulfides, gel electrolytes, or composite electrolytes made of ceramics and polymers can be used.

[0079] Examples of oxides include LISICON-type oxides such as γ-Li3PO4, Li3BO4, 0.75Li4GeO4-0.25Li2ZnGeO4 solid solution, Li4SiO4-Zn2SiO4 solid solution, Li4GeO4-Li3VO4 solid solution, and NASICON-type oxides such as Li 1.3 Al 0.3 Ti 1.7 (PO4)3 or Li 1.6 Al 0.6 Ge 0.8 Ti 0.6 (PO4)3, (Li,La)TiO3 which has a perovskite structure, and La5Li3Nb2O which is a garnet-type oxide. 12 Li5La3TaO 12 , or Li7La3Zr2O 12 These are some examples.

[0080] Examples of sulfides include Li4GeS4-Li3PS4 solid solution, Li4SiS4-Li3PS4 solid solution, Li3PS4-Li2S solid solution, Li2S-P2S5 solid solution, Li2S-SiS2, Li 10 GeP2S 12 Argyrodite-type Li6PS5X (X=Cl, Br, I), or L7P3S 11 Crystals are an example.

[0081] (Ceramic solid electrolyte for sodium-ion secondary batteries) As an oxide, NASICON type Na 1+x Zr2Si x P 3-x O 12 Examples include (0≦x≦1) or the β-alumina type Na2O-11Al2O3. Examples of sulfides include Na2S-P2S5, Na3PS4, Na3SbS4, Na2S-SiS2, or Na2S-GeS2. Examples of selenides include Na3PSe4.

[0082] (Gel electrolyte) The gel electrolyte comprises a resin and a non-aqueous electrolyte, ionic liquid, grime, or electrolyte salt. Examples of resins for gel electrolytes include the polymers or polymerizable monomers used in the binders mentioned above.

[0083] The electrode liquid composition used when printing alignment marks 300 may be an electrode liquid composition containing conductive materials such as positive electrode active material, negative electrode active material, or conductive additive, or it may be an electrode liquid composition containing insulating materials such as solid electrolyte or semi-solid electrolyte. From a safety standpoint, printing with an electrode liquid composition made of insulating materials such as solid electrolyte or semi-solid electrolyte is more preferable, considering adhesion to the electrode composite layer due to detachment during cutting.

[0084] (Non-aqueous electrolyte) Mix at least one of the above-mentioned resins for gel electrolytes with a non-aqueous electrolyte containing an electrolyte salt, such that the weight ratio of the non-aqueous electrolyte to the resin is in the range of 50% to 2000%. The concentration of the electrolyte salt in the non-aqueous electrolyte can be appropriately selected depending on the purpose, but for swing-type energy storage elements, it is preferably 1 mol / L to 2 mol / L, and for reserve-type energy storage elements, it is preferably 2 mol / L to 4 mol / L. There are no particular restrictions on the non-aqueous electrolyte, and it can be appropriately selected depending on the purpose, but an aprotic organic solvent is preferred.

[0085] As the aprotic organic solvent, carbonate-based organic solvents such as linear carbonates or cyclic carbonates can be used. Among these, linear carbonates are preferred due to their high solubility of the electrolyte salt. Furthermore, aprotic organic solvents with low viscosity are preferred from the viewpoint of discharge stability.

[0086] Examples of linear carbonates include dimethyl carbonate (DMC), diethyl carbonate (DEC), or methyl ethyl carbonate (EMC).

[0087] There are no particular restrictions on the content of linear carbonates in the non-aqueous solvent, and it can be appropriately selected depending on the purpose, but it is preferable that it be 50% by mass or more. When the content of linear carbonates in the non-aqueous solvent is 50% by mass or more, even if the solvent other than the linear carbonates is a cyclic substance with a high dielectric constant (e.g., cyclic carbonate or cyclic ester), the content of the cyclic substance will be low. For this reason, even when a non-aqueous electrolyte with a high concentration of 2M or more is prepared, the viscosity of the non-aqueous electrolyte will be low, and the penetration of the non-aqueous electrolyte into the electrode and ion diffusion will be good.

[0088] Examples of cyclic carbonates include propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate (BC), and vinylene carbonate (VC).

[0089] In addition, as a non-aqueous solvent other than carbonate-based organic solvents, ester-based organic solvents such as cyclic esters or linear esters, cyclic ethers, or linear ethers may be used as necessary.

[0090] Examples of cyclic esters include γ-butyrolactone (γBL), 2-methyl-γ-butyrolactone, acetyl-γ-butyrolactone, or γ-valerolactone.

[0091] Examples of linear esters include alkyl propionate esters, dialkyl malonate esters, alkyl acetate esters (methyl acetate (MA), or ethyl acetate, etc.), or alkyl formate esters (methyl formate (MF), or ethyl formate, etc.).

[0092] Examples of cyclic ethers include tetrahydrofuran, alkyltetrahydrofuran, alkoxytetrahydrofuran, dialkoxytetrahydrofuran, 1,3-dioxolane, alkyl-1,3-dioxolane, or 1,4-dioxolane.

[0093] Examples of linear ethers include 1,2-dimethylethane (DME), diethyl ether, ethylene glycol dialkyl ether, diethylene glycol dialkyl ether, triethylene glycol dialkyl ether, or tetraethylene glycol dialkyl ether.

[0094] (Ionic liquid) As an ionic liquid, the cation species is Li + or Na + The compound contains at least one of BMP (1-butyl-1-methylpyrrolidinium), EMI (1-ethyl-3-methylimidazolium), and BMMI (1-butyl-2,3-dimethylimidazolium), and the anionic species may be TFSI (bis(trifluoromethaneSulfonyl)imide) or FSI (bisfluorosulfonyl)imide.

[0095] (Grime) As a grime, RO-(CHCHO) generally forms a stable Lewis acid-base type 1:1 complex cation. n -Triphlyme (G3) or tetraglyme (G4) with n=3 or 4 of R can be used.

[0096] (Electrolyte salts) The electrolyte salt is not particularly limited as long as it has high ionic conductivity and is soluble in a non-aqueous solvent. The electrolyte salt preferably contains a halogen atom. Examples of cations constituting the electrolyte salt include lithium ions or sodium ions. Examples of anions constituting the electrolyte salt include BF4. - PF6 - AsF6 - CF3SO3 - , (CF3SO2)2N - (C2F5SO2)2N - (C2F5SO2)2N - , (FSO2)2N - , or (CF3SO2)3C - These are some examples.

[0097] There are no particular restrictions on the lithium salt, and it can be appropriately selected depending on the purpose. Examples include lithium hexafluorophosphate (LiPF6), lithium borate (LiBF4), lithium arsenide hexafluoride (LiAsF6), lithium trifluoromethasulfonate (LiCF3SO3), lithium bis(trifluoromethylsulfonyl)imide (LiN(CF3SO2)2), lithium (bispentafluoroethylsulfonyl) or imide (LiN(C2F5SO2)2), etc. Among these, LiPF6 is preferred in terms of ionic conductivity, and LiBF4 is preferred in terms of stability.

[0098] There are no particular restrictions on the sodium salt used, and it can be appropriately selected depending on the purpose. Examples include sodium hexafluorophosphate (NaPF6), sodium borofluoride (NaBF4), sodium arsenic hexafluoride (NaAsF6), sodium trifluoromethasulfonate (NaCF3SO3), sodium bis(trifluoromethylsulfonyl)imide (NaN(CF3SO2)2), or sodium (bispentafluoroethylsulfonyl)imide (NaN(C2F5SO2)2). The electrolyte salt may be used alone or in combination of two or more types.

[0099] (Inorganic particles) Furthermore, the gel electrolyte may also contain inorganic particles. Examples of inorganic particles include silica (SiO2), alumina (Al2O3), LISICON-type oxides of oxide solid electrolyte materials such as γ-Li3PO4, Li3BO4, 0.75Li4GeO4-0.25Li2ZnGeO4 solid solution, Li4SiO4-Zn2SiO4 solid solution, Li4GeO4-Li3VO4 solid solution, and NASICON-type oxides such as Li 1.3 Al 0.3 Ti 1.7 (PO4)3 or Li 1.6 Al 0.6 Ge 0.8 Ti 0.6 (PO4)3, (Li,La)TiO3 which has a perovskite structure, and La5Li3Nb2O which is a garnet-type oxide. 12 Li5La3TaO 12 , or Li7La3Zr2O 12 These are some examples. At least one of these inorganic particles is mixed with an ionic liquid such that the weight ratio of the ionic liquid to the inorganic particles is in the range of 50% to 200%.

[0100] (Method for manufacturing electrode liquid composition) To manufacture the electrode liquid composition, the active material is dispersed in a dispersion medium, an ionic liquid, a grime, and a non-aqueous electrolyte. The average particle size of the active material is preferably 10 μm or less, and more preferably 5 μm or less. When the average particle size of the active material is 10 μm or less, the discharge stability and sedimentation resistance of the electrode liquid composition are improved. The d10 of the active material is preferably 0.1 μm or more, and more preferably 0.15 μm or more. When the d10 of the active material is 0.1 μm or more, the storage stability of the electrode liquid composition is improved. The electrode liquid composition of the first embodiment may further contain, as necessary, conductive additives, dispersants, binders, solid electrolytes, gel electrolytes, or monomers that become gel electrolytes through a polymerization process. The viscosity of the electrode liquid composition at 25°C is preferably in the range of 3 mPa·s to 100 mPa·s. More preferably, it is 9 mPa·s to 50 mPa·s.

[0101] Here, the average particle diameter refers to the volume-average particle diameter based on the effective diameter, and the average particle diameter is measured by, for example, laser diffraction / scattering or dynamic light scattering. Furthermore, the viscosity of the electrode liquid composition at 25°C is measured at 100 rpm using a Type B viscometer (cone plate viscometer) equipped with a rotor No. CPA-40Z.

[0102] (Formation of separators) As shown in Figure 4 or Figure 5, after acquiring positional information of the electrode composite layer 12 by image recognition, an insulating layer liquid composition 21B containing a polymerizable compound for forming an electronic insulating layer 21 is inkjet printed onto the electrode composite layer 12 as shown in Figure 10. At this time, the insulating layer liquid composition 21B is applied so as to cover the entire electrode composite layer 12 (top and sides). The insulating layer liquid composition 21B forms a crosslinkable structure by irradiation with light or heat, and becomes an electronic insulating layer 21 when dried. Note that the insulating layer liquid composition 21B is an example of a liquid composition that does not contain an active material but contains an electronic insulating layer forming material.

[0103] (Electron insulating layer forming material) The polymerizable compound is a precursor of the resin for forming the electronic insulating layer 21, and is not particularly limited as long as it is a resin that can form a crosslinkable electronic insulating layer by irradiation with light or heat. Examples include acrylate resins, methacrylate resins, urethane acrylate resins, vinyl ester resins, unsaturated polyesters, epoxy resins, oxetane resins, vinyl ethers, or resins that utilize the en-thiol reaction. Among these, acrylate resins, methacrylate resins, urethane acrylate resins, or vinyl ester resins are particularly preferred from the viewpoint of productivity because their high reactivity allows for easy formation of the electronic insulating layer using radical polymerization.

[0104] The above resin can be cured by light or heat by preparing a mixture of polymerizable monomers and compounds that generate radicals or acids by light or heat. Furthermore, in order to form the electronically insulating layer 21 by polymerization-induced phase separation, an ink can be prepared by pre-mixing pologen with the above mixture.

[0105] Polymerizable compounds have at least one radical polymerizable functional group. Examples include monofunctional, difunctional, or trifunctional or more radical polymerizable compounds, functional monomers, and radical polymerizable oligomers. Among these, difunctional or more radical polymerizable compounds are particularly preferred.

[0106] Examples of monofunctional radical polymerizable compounds include 2-(2-ethoxyethoxy)ethyl acrylate, methoxypolyethylene glycol monoacrylate, methoxypolyethylene glycol monomethacrylate, phenoxypolyethylene glycol acrylate, 2-acryloyloxyethyl succinate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, tetrahydrofurfuryl acrylate, 2-ethylhexyl carbitol acrylate, 3-methoxybutyl acrylate, benzyl acrylate, cyclohexyl acrylate, isoamyl acrylate, isobutyl acrylate, methoxytriethylene glycol acrylate, phenoxytetraethylene glycol acrylate, cetyl acrylate, isostearyl acrylate, stearyl acrylate, or styrene monomer. These may be used individually or in combination of two or more.

[0107] Examples of bifunctional radical polymerizable compounds include 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, diethylene glycol diacrylate, polyethylene glycol diacrylate, neopentyl glycol diacrylate, EO-modified bisphenol A diacrylate, EO-modified bisphenol F diacrylate, neopentyl glycol diacrylate, or tricyclodecanedimethanol diacrylate. These may be used individually or in combination of two or more.

[0108] Examples of radical polymerizable compounds with three or more functions include trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate, EO-modified trimethylolpropane triacrylate, PO-modified trimethylolpropane triacrylate, caprolactone-modified trimethylolpropane triacrylate, HPA-modified trimethylolpropane trimethacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate (PETTA), glycerol triacrylate, ECH-modified glycerol triacrylate, EO-modified glycerol triacrylate, PO-modified glycerol triacrylate, and Tris Examples include (acryloxyethyl) isocyanurate, dipentaerythritol hexaacrylate (DPHA), caprolactone-modified dipentaerythritol hexaacrylate, dipentaerythritol hydroxypentaacrylate, alkyl-modified dipentaerythritol pentaacrylate, alkyl-modified dipentaerythritol tetraacrylate, alkyl-modified dipentaerythritol triacrylate, dimethylolpropane tetraacrylate (DTMPTA), pentaerythritol ethoxytetraacrylate, EO-modified phosphate triacrylate, or 2,2,5,5-tetrahydroxymethylcyclopentanone tetraacrylate. These may be used individually or in combination of two or more.

[0109] As photopolymerization initiators, photoradical generators can be used. For example, photoradical polymerization initiators such as Michler ketone and benzophenone, known by trade names Irgacure and Darocure, and more specifically, benzophenone, acetophenone derivatives, such as α-hydroxy- or α-aminocetophenone, 4-aloyl-1,3-dioxolane, benzyl ketal, 2,2-diethoxyacetophenone, p-dimethylaminoacetophenone, p-dimethylaminopropiophenone, benzophenone, 2-chlorobenzophenone, pp'-dichlorobenzophenone, pp'-bis-diethylaminobenzophenone, Michler's ketone, benzyl, benzoin, benzyldimethyl ketal, tetramethylthiuram monosulfide, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, azobisisobutyronitrile, benzoin peroxide, di-tert-butyl peroxide, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropyl Pan-1-one, methylbenzoylformate, zoin isopropyl ether, benzoin methyl ether, benzoin ethyl ether, ben ether, benzoin isobutyl ether, benzoin n-butyl ether, benzoin n-propyl, and other benzoin alkyl ethers and esters, 1-hydroxycyclohexyl-phenyl-ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 1-hydroxycyclohexyl-phenyl-ketone, 2,2-dimethyl Xy-1,2-diphenylethane-1-one, bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole-1-yl)-phenyl)titanium, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2-methyl-1[4-(methylthio)phenyl]-2-molifolinopropan-1-one, 2-hydroxy-2-methyl-1-phenyl-propan-1-one (Darocure 1173), bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one monoacylphosphine oxide, bisacylphosphine oxide or titanocene, fluorescene, anthraquinone, thioxanthone or xanthone, rhofin dimer, trihalomethyl or dihalomethyl compounds, active ester compounds, organoboron compounds, etc. are preferably used.

[0110] Furthermore, photocrosslinking radical generators such as bisazide compounds may be included simultaneously. Also, when polymerization is carried out by heat alone, conventional thermal polymerization initiators such as A(AIBN), which are typical photoradical generators, can be used.

[0111] Alternatively, a similar function can be achieved by preparing a mixture of a photoacid generator that generates acid upon light irradiation and at least one monomer that polymerizes in the presence of acid. When light is irradiated onto such a liquid ink, the photoacid generator generates acid, which functions as a catalyst for the crosslinking reaction of polymerizable compounds.

[0112] Furthermore, the generated acid diffuses within the ink layer. Moreover, the diffusion of the acid and the acid-catalyzed crosslinking reaction can be accelerated by heating, and unlike radical polymerization, this crosslinking reaction is not inhibited by the presence of oxygen. The resulting resin layer also exhibits superior adhesion compared to the radical polymerization system.

[0113] Polymerizable compounds that can be crosslinked in the presence of acid include compounds having cyclic ether groups such as epoxy groups, oxetane groups, and oxolane groups; acrylic or vinyl compounds having the above-mentioned substituents in their side chains; carbonate compounds; low molecular weight melamine compounds; vinyl ethers and vinylcarbazoles; styrene derivatives; alpha-methylstyrene derivatives; vinyl alcohol esters including ester compounds of vinyl alcohol with acrylic and methacrylic; and monomers having a vinyl bond that can be cationically polymerized.

[0114] Examples of photoacid generators that produce acid upon light irradiation include onium salts, diazonium salts, quinone diazide compounds, organic halides, aromatic sulfonate compounds, bisulfone compounds, sulfonyl compounds, sulfonate compounds, sulfonium compounds, sulfamide compounds, iodonium compounds, or sulfonyl diazomethane compounds, and mixtures thereof.

[0115] In particular, onium salts are preferred as photoacid generators. Examples of usable onium salts include diazonium salts, phosphonium salts, and sulfonium salts with fluoroborate anion, hexafluoroantimonate anion, hexafluoroarsenate anion, trifluoromethanesulfonate anion, p-toluenesulfonate anion, and p-nitrotoluenesulfonate anion as counterions. In addition, halogenated triazine compounds can also be used as photoacid generators.

[0116] The photoacid generator may optionally further contain a sensitizing dye. Examples of sensitizing dyes include acridine compounds, benzoflavins, perylene, anthracene, and laser dyes.

[0117] Pologen is mixed in to form vacancies in the cured electronic insulating layer 21. Any liquid substance can be selected as pologen, as long as it is capable of dissolving the polymerizable monomer and the compound that generates radicals or acids upon exposure to light or heat, and can cause phase separation during the polymerization process of the polymerizable monomer and the compound that generates radicals or acids upon exposure to light or heat.

[0118] Examples of pologenes include ethylene glycols such as diethylene glycol monomethyl ether, ethylene glycol monobutyl ether, and dipropylene glycol monomethyl ether; esters such as γ-butyrolactone and propylene carbonate; and amides such as NN-dimethylacetamide.

[0119] Furthermore, liquid substances with relatively large molecular weights, such as methyl tetradecanoate, methyl decanoate, methyl myristate, and tetradecane, also tend to function as pologenes. In particular, many ethylene glycols have high boiling points. The phase separation mechanism is highly dependent on the concentration of pologenes in the structure that is formed. Therefore, using the above liquid substances makes it possible to form a stable electronic insulating layer 21. Pologenes may be used alone or in combination of two or more types.

[0120] Furthermore, similar to the first embodiment, the substrate 11 is cut out at any position in the region where the electronic insulating layer 21 is not formed (the region where the insulating layer liquid composition 21B is not applied). As a result, as shown in Figures 7 and 8, exposure of the electrode composite layer 12 can be prevented in the electrode 20, and an electrode end structure can be obtained that can prevent short circuits inside the battery due to the sliding of active material, etc.

[0121] (Printing on the current collector) Figure 11 is a plan view illustrating an electrode according to a modified example of the second embodiment. Figure 12 is a cross-sectional view illustrating an electrode according to a modified example of the second embodiment, showing a cross-section along the CC line in Figure 11. When an insulating substrate is used for the base material 11, it is necessary to form an electrically conductive layer 31 for current collection, as shown in the electrode 30 in Figures 11 and 12. A portion of the electrically conductive layer 31 is exposed at the edge of the electronically insulating layer 21.

[0122] To form the electrically conductive layer 31, a conductive liquid composition is prepared containing, for example, at least one metal nanoparticle or fiber of silver, copper, gold, nickel, and aluminum, or a highly conductive carbon material such as carbon nanotubes or graphene, or a conductive ceramic such as titanium nitride.

[0123] Then, the above liquid composition is dispensed onto the insulating substrate 11 by inkjet printing to form an electrically conductive layer 31. With inkjet printing, the electrically conductive layer 31 can be formed in any shape and at any location on the substrate 11.

[0124] The average particle size of the dispersion in the liquid composition for forming the electrically conductive layer is preferably 0.01 μm or more and 3 μm or less, and the viscosity of the liquid composition for forming the electrically conductive layer at 25°C is preferably in the range of 3 mPa·s or more and 18 mPa·s or less.

[0125] If the average particle size of the dispersed state in the liquid composition for forming the electrically conductive layer is 0.01 μm or larger, the discharge stability of the liquid composition is stable, and if it is 3 μm or smaller, the storage stability of the liquid composition is improved. Furthermore, if the viscosity of the liquid composition for forming the electrically conductive layer at 25°C is in the range of 3 mPa·s to 18 mPa·s, it becomes easier to discharge as droplets, making it easier to control the discharge amount.

[0126] After the printing process, the liquid composition can be fired by a firing method commonly used in this field. In the case of metal nanoparticles, more preferably 10 in order to prevent oxidation. -4 Drying and sintering are performed under a vacuum of Pa or less, in a nitrogen atmosphere, or in an argon atmosphere. To improve sinterability, light sintering using a xenon flash lamp can also be used.

[0127] <Third Embodiment> In the third embodiment, an example of an electrode having electrode composite layers on both sides of the substrate is shown. Figure 13 is a cross-sectional view illustrating the electrode according to the third embodiment. The plan view of the electrode according to the third embodiment is the same as that of Figure 1.

[0128] As shown in Figure 13, the electrode 40 differs from the electrode 10 (see Figures 1 and 2) in that an electrode composite layer 42 is formed on the other surface 11b of the base material 11. The electrode composite layer 42 is formed, for example, in a position that overlaps with the electrode composite layer 12 in a plan view. The thickness of the electrode composite layer 42 is, for example, the same as the thickness of the electrode composite layer 12.

[0129] On the other surface 11b of the substrate 11, the uncoated portion 11p is provided in an annular shape outside the outer peripheral portion 42p of the electrode composite layer 42 in a plan view. The uncoated portion 11p is the portion of the other surface 11b of the substrate 11 that is exposed without being covered by the electrode composite layer 42. The uncoated portion 11p is formed, for example, at a position that overlaps with the uncoated portion 11m in a plan view.

[0130] (Both sides coated) Figure 14 illustrates an electrode manufacturing method according to the third embodiment. As shown in Figure 14(a), after cutting out the substrate 11 on which the electrode composite layer 12 is formed, the substrate 11 is inverted vertically as shown in Figure 14(b), and the position information of the electrode composite layer 12 is obtained by image recognition of the cut edge of the substrate 11 with an image sensor 102B. Then, as shown in Figure 14(c), an electrode liquid composition containing electrode composite 42A is applied to the other surface 11b of the substrate 11 so as to overlap with the position of the electrode composite layer 12 in a plan view. The electrode liquid composition containing electrode composite 42A can be applied using an inkjet head 101B in the same manner as the electrode liquid composition containing electrode composite 12A. The electrode liquid composition containing electrode composite 42A may have the same composition as the electrode liquid composition containing electrode composite 12A, or it may have a different composition.

[0131] The method of recognizing the end shape of the substrate 11 with an image sensor 102B to determine the position of the substrate 11 may also be used in the case of single-sided coating. For example, when manufacturing the electrode 20 shown in Figure 7, etc., in a structure in which an electrode composite layer 12 is formed on the substrate 11, only the substrate 11 may be cut, and then the end shape of the substrate 11 may be recognized with an image sensor 102B, and an electrolyte liquid composition 21A or insulating layer liquid composition 21B that covers the electrode composite layer 12 may be applied.

[0132] (Bipolar application) In particular, a bipolar electrode can be formed by applying an electrode liquid composition containing electrode material 42A having a different polarity from the electrode liquid composition containing electrode material 12A. Alternatively, as shown in Figure 15, an electronic insulating layer 21 and 51 covering the electrode liquid composition layers 12 and 42 may be formed on one surface 11a and the other surface 11b of the substrate 11.

[0133] On the other surface 11b of the substrate 11, the uncoated portion 11q is provided in an annular shape outside the outer peripheral portion 51p of the electronic insulating layer 51 in a plan view. The uncoated portion 11q is the portion of the other surface 11b of the substrate 11 that is exposed without being covered by the electrode composite layer 42 or the electronic insulating layer 51. The uncoated portion 11q is formed, for example, at a position that overlaps with the uncoated portion 11n in a plan view.

[0134] The coating on the other side 11b may be performed between the step of coating the electrode liquid composition containing the electrode mixture 12A onto the substrate 11 and the step of cutting only the substrate 11, as shown in Figure 16. In Figure 16, the alignment marks 310 are through holes formed in the substrate 11 by laser processing. In this case, by image recognition of the alignment marks 310, it is possible to obtain positional information of the electrode liquid composition containing the electrode mixture 12A from the other side 11b of the substrate 11.

[0135] First, as shown in Figure 16(a), an electrode liquid composition containing electrode material 12A is applied to one surface 11a of the substrate 11. Then, as shown in Figure 16(b), the substrate 11 is inverted, and the alignment mark 310 is image-recognized from the other surface 11b of the substrate 11 using the image sensor 102B to read the position information of the electrode liquid composition containing electrode material 12A. Then, as shown in Figure 16(c), the inkjet head 101B applies an electrode liquid composition containing electrode material 42A to the other surface 11b of the substrate 11 so that, in a plan view, it overlaps with the application position of the electrode liquid composition containing electrode material 12A.

[0136] Furthermore, if the alignment marks are visible only from one side 11a of the substrate 11, it is possible to perform image recognition of the alignment marks from one side 11a of the substrate 11 and apply the electrode liquid composition containing the electrode mixture 42A to the other side 11b, timing the application based on the transport speed of the substrate 11.

[0137] (electrode manufacturing equipment) Figure 17 is a schematic diagram illustrating an electrode manufacturing apparatus. As shown in Figure 17, the electrode manufacturing apparatus 100A includes an inkjet head 101A, image sensors 102A and 102B, a transport belt 103, a laser head 104, a control device 130, an inkjet printing control board 140, image sensor control boards 150A and 150B, and a laser processing control board 160. The control device 130 can issue various commands to the inkjet printing control board 140, the image sensor control boards 150A and 150B, and the laser processing control board 160.

[0138] The inkjet head 101A is an example of a means for applying an electrode liquid composition containing electrode material to any position on a substrate in any shape. The image sensors 102A and 102B are examples of means for acquiring positional information of the applied electrode liquid composition containing electrode material. The laser head 104 is an example of a means for cutting only the substrate at any position in the area excluding the electrode liquid composition area to which the electrode liquid composition containing electrode material has been applied, thereby cutting out an electrode in any shape. The electrode manufacturing apparatus 100A can control the arbitrary position to apply the electrode liquid composition containing electrode material, the arbitrary shape of the electrode liquid composition containing electrode material, and the arbitrary position to cut the substrate using digital data.

[0139] Figure 18 is an example of a main hardware block diagram of a control device. As shown in Figure 18, in the electrode manufacturing apparatus 100A, the control device 130 includes a CPU 131, a ROM 132, a RAM 133, an NVRAM 134, an ASIC 135, an I / O 136, and an operation panel 137.

[0140] The CPU 131 controls the entire electrode manufacturing apparatus 100A. The ROM 132 stores programs executed by the CPU 131 and other fixed data. The RAM 133 temporarily stores data related to electrode manufacturing. The NVRAM 134 is a non-volatile memory that retains data even when the power to the apparatus is cut off. The ASIC 135 processes image processing, including various signal processing and sorting of image data, and input / output signals for controlling the entire apparatus. The I / O 136 is an interface for inputting and outputting signals to the inkjet printing control board 140, image sensor control boards 150A and 150B, and laser processing control board 160. The operation panel 137 inputs and displays information necessary for the control device 130.

[0141] Figure 19 is an example of a main functional block diagram of a control device. As shown in Figure 19, the control device 130 has a head control unit 1301, a sensor control unit 1302, and a laser control unit 1303 as functional blocks.

[0142] The head control unit 1301 issues a drive command to the inkjet printing control board 140 at a specified timing and number of drops based on the given waveform data and discharge conditions such as the discharge frequency. The sensor control unit 1302 issues commands to the image sensor control boards 150A and 150B to acquire necessary information, including position information of the electrode liquid composition containing the electrode mixture, from the image sensors 102A and 102B. The laser control unit 1303 issues commands to the laser processing control board 160 to control the required amount of emitted light to cut the substrate 11, and to scan the laser beam based on the position information of the electrode liquid composition containing the electrode mixture acquired by the sensor control unit 1302.

[0143] By using the electrode manufacturing apparatus 100A shown in Figures 17 to 19, the design can be changed by transferring digital data, electrodes of any shape can be formed by inkjet printing, and electrodes of any shape can be cut out by laser processing. In this way, electrode shape design data is transferred from the control device 130 to the inkjet printing control board 140, the image sensor control boards 150A and 150B, and the laser processing control board 160, respectively. This makes it possible to switch to manufacturing electrodes with different designs without changing the setup, such as redesigning or replacing masks and plates.

[0144] (Environment during the coating process) Furthermore, the liquid compositions used as electrodes or electrolytes contain materials that react with moisture in the atmosphere, causing performance degradation. In particular, sulfide solid electrolytes are known to generate toxic hydrogen sulfide gas when they react with moisture, requiring strict moisture control. In processes where these moisture-reactive materials are exposed, it is preferable to maintain an inert gas environment such as dry air with a low dew point, nitrogen, or argon. At least the application of the electrode liquid composition, including the electrode mixture, is preferably carried out in an environment filled with dry air or an inert gas with a dew point of -40°C or lower. Moreover, it is more preferable that the environment filled with dry air or an inert gas is under positive pressure relative to the external environment.

[0145] According to the electrode manufacturing method of the first embodiment, etc., a series of electrode manufacturing processes from coating to electrode cutting can be controlled solely by the exchange of digital data, enabling remote operation. For example, the coating of the electrode liquid composition containing the electrode composite material can be performed in an environment filled with dry air or inert gas with a dew point of -40°C or lower, and the coating position and coating shape of the electrode liquid composition containing the electrode composite material can be changed while maintaining this environment.

[0146] For example, as shown in Figure 20, by creating a locally moisture-controlled environment only in the limited space 170 surrounding the process of applying the liquid composition or cutting the substrate, electrode manufacturing becomes possible while ensuring performance and safety. Consequently, costs associated with production line stoppages and setup changes due to design changes, as well as running costs due to atmosphere control in the restricted space, can be reduced, enabling low-cost electrode manufacturing.

[0147] Although preferred embodiments have been described in detail above, the invention is not limited to the embodiments described above, and various modifications and substitutions can be made to the embodiments described above without departing from the scope of the claims. [Explanation of symbols]

[0148] 10, 20, 30, 40, 50 electrodes 11 Base material 11a One side of the substrate 11 11b The other side of the base material 11 11c position 11e End of base material 11 11m, 11n, 11p, 11q Unpainted section 12, 42 Electrode composite layer 12A, 42A electrode mixture 12p Outer periphery of electrode composite layer 12 21 Electronic insulating layer 21A Electrolyte liquid composition 21B Insulating Layer Liquid Composition 21p Outer periphery of the electronic insulating layer 21 31 Electrical Conductive Layer 42p Outer periphery of electrode composite layer 42 51p Outer periphery of the electronic insulating layer 51 100, 100A electrode manufacturing equipment 101A, 101B inkjet heads 102A, 102B image sensors 103 Conveyor belt 104 Laser Head 104L laser light 130 Control device 131 CPU 132 ROM 133 RAM 134 NVRAM 135 ASIC 136 I / O 137 Control Panel 140 Inkjet Printing Control Board 150A, 150B Image Sensor Control Board 160 Laser Processing Control Board 300, 310 Alignment Marks 1301 Head Control Unit 1302 Sensor Control Unit 1303 Laser Control Unit [Prior art documents] [Patent Documents]

[0149] [Patent Document 1] Japanese Patent Publication No. 2018-129222 [Patent Document 2] Patent No. 6432990 [Patent Document 3] Japanese Patent Publication No. 2012-221912 [Patent Document 4] Japanese Patent Publication No. 2018-37143

Claims

1. A first step involves applying an electrode liquid composition containing an electrode mixture to a substrate at any position and in any shape. A second step of acquiring positional information of the electrode liquid composition containing the electrode mixture material to which the electrode liquid composition has been applied, The third step involves cutting only the substrate at an arbitrary position in an area other than the electrode mixture area to which the electrode liquid composition containing the electrode mixture is applied, thereby cutting out an electrode in an arbitrary shape. An electrode manufacturing method characterized in that, in the second step, the position information is obtained by image recognition of a mark formed by printing the electrode liquid composition containing the electrode mixture in an area excluding the electrode mixture area.

2. A first step involves applying an electrode liquid composition containing an electrode mixture to a substrate at any position and in any shape. A second step of acquiring positional information of the electrode liquid composition containing the electrode mixture material to which the electrode liquid composition has been applied, The third step involves cutting only the substrate at an arbitrary position in an area other than the electrode mixture area to which the electrode liquid composition containing the electrode mixture is applied, thereby cutting out an electrode in an arbitrary shape. An electrode manufacturing method characterized in that at least the first step is carried out in an environment filled with dry air or an inert gas with a dew point of -40°C or lower, and the application position and application shape of the electrode liquid composition containing the electrode composite material can be changed while maintaining the environment.

3. The electrode manufacturing method according to claim 2, characterized in that, in the second step, the position information is obtained by image recognition of the end shape of the electrode composite region.

4. The electrode manufacturing method according to claim 2, characterized in that the second step involves acquiring the positional information by image recognition of the holes formed in the substrate.

5. The electrode manufacturing method according to claim 2, characterized in that the second step involves cutting the substrate in an arbitrary shape and obtaining the position information by image recognition of the cut edge of the substrate.

6. The electrode manufacturing method according to any one of claims 1 to 5, characterized in that the arbitrary position, arbitrary shape, and arbitrary position for cutting the substrate in the first to third steps are controllable by a control device.

7. The electrode manufacturing method according to claim 6, characterized in that the control device controls the arbitrary position, arbitrary shape, and arbitrary position for cutting the substrate of the electrode liquid composition containing the electrode mixture using digital data.

8. The electrode manufacturing method according to any one of claims 1 to 7, characterized in that the first step involves discharging the electrode liquid composition containing the electrode mixture from a nozzle.

9. The electrode manufacturing method according to any one of claims 1 to 8, characterized in that the third step involves cutting only the substrate with laser light.

10. The electrode manufacturing method according to any one of claims 1 to 9, characterized in that the substrate is a single sheet of metal foil or an insulating substrate.

11. The electrode manufacturing method according to any one of claims 1 to 9, characterized in that the substrate is a strip-shaped metal foil or an insulating substrate.

12. In the first step described above, an electrode liquid composition containing an active material is applied to form an electrode liquid composition containing the electrode mixture, An electrode manufacturing method according to any one of claims 1 to 11, further comprising the step of applying a liquid composition containing an electronic insulating layer forming material but not the active material onto the electrode composite layer, after the first step, to form an electronic insulating layer on the electrode composite layer that covers the entire electrode composite layer.

13. The electrode manufacturing method according to any one of claims 1 to 12, characterized in that between the first step and the second step, the step of inverting the substrate and applying the electrode liquid composition containing the electrode mixture to any position on the side of the substrate where the electrode liquid composition containing the electrode mixture has not been applied.

14. A first means for applying an electrode liquid composition containing an electrode mixture to a substrate at any position and in any shape, A second means for acquiring positional information of the electrode liquid composition containing the electrode mixture material to which the electrode liquid composition has been applied, A third means for cutting only the substrate at an arbitrary position in an area other than the electrode mixture area to which the electrode liquid composition containing the electrode mixture is applied, thereby cutting out an electrode in an arbitrary shape, The system includes a control device capable of controlling the arbitrary position, arbitrary shape, and arbitrary position for cutting the substrate of the electrode liquid composition comprising the electrode mixture in the first to third means described above. The second means is an electrode manufacturing apparatus that acquires positional information by image recognition of a mark formed by printing an electrode liquid composition containing the electrode mixture in an area excluding the electrode mixture area.

15. A first means for applying an electrode liquid composition containing an electrode mixture to a substrate at any position and in any shape, A second means for acquiring positional information of the electrode liquid composition containing the electrode mixture material to which the electrode liquid composition has been applied, A third means for cutting only the substrate at an arbitrary position in an area other than the electrode mixture area to which the electrode liquid composition containing the electrode mixture is applied, thereby cutting out an electrode in an arbitrary shape, The system includes a control device capable of controlling the arbitrary position, arbitrary shape, and arbitrary position for cutting the substrate of the electrode liquid composition comprising the electrode mixture in the first to third means described above. At least the first means is an electrode manufacturing apparatus capable of changing the application position and application shape of the electrode liquid composition containing the electrode mixture while maintaining an environment filled with dry air or an inert gas with a dew point of -40°C or lower.

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