Method for manufacturing a composite electrode and apparatus for manufacturing a composite electrode

Abstract

Embodiments of the present application relate to a manufacturing method of a composite electrode and a manufacturing apparatus of a composite electrode, and have high yield and material efficiency. According to the embodiments, a manufacturing method of a composite electrode provided with a base material and an insulating fiber film provided on the base material is provided. The manufacturing method includes: applying a primer solution on a base material in a tape shape; and discharging a charged raw material liquid in a direction parallel to a main surface of the base material that intersects with a side surface of the base material and stacking the raw material liquid on the base material, thereby forming the insulating fiber film on the main surface of the base material.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to a manufacturing method of a composite electrode and a manufacturing apparatus of a composite electrode. BACKGROUND

[0002] There is an electrospinning device that forms a fiber film by accumulating fine fibers on the surface of a collector or a substrate by an electrospinning method (sometimes also referred to as an electric field spinning method, a charge-induced spinning method, and the like). In an example of the electrospinning device, an electrospinning head is provided, and the electrospinning head includes a head main body and a nozzle that protrudes from the outer peripheral surface of the head main body. In the electrospinning head, a storage cavity that can store a raw material liquid is formed in the inside of the head main body. In addition, a flow path (nozzle flow path) that communicates with the storage cavity is formed in the inside of the nozzle, and a nozzle outlet of the flow path is formed in the protruding end of the nozzle that protrudes from the head main body. By applying a voltage between the nozzle (electrospinning head) and the collector or the substrate, the raw material liquid is ejected from the nozzle outlet of the flow path toward the surface of the collector or the substrate, and the fibers are accumulated on the surface of the collector or the substrate.

[0003] As a use of the fiber film thus formed, for example, a separator and the like used in an electric power storage device such as a lithium ion secondary battery, an electric double layer capacitor, and the like, and a separation film that requires electrical insulation are known. In addition, due to the spread of portable electronic devices and the like, miniaturization of the electric power storage device is desired. In the electrospinning method, the fibers that are ejected toward the surface of the collector or the substrate are accumulated over a relatively large range. Therefore, when the film obtained by the electrospinning method is applied to a small electric power storage device, further processing is required or waste of the material is generated. Therefore, with respect to the formation of a small-sized film, improvement of production efficiency and material efficiency is desired. SUMMARY

[0004] An object of the embodiments is to provide a manufacturing method of a composite electrode and a manufacturing apparatus thereof, which have high yield and material efficiency.

[0005] According to the embodiments, a manufacturing method of a composite electrode that includes a substrate and an insulating fiber film provided on the substrate is provided. The manufacturing method includes: applying a primer solution on a substrate in a belt shape; and forming an insulating fiber film on a main surface of the substrate by ejecting a charged raw material liquid in a direction parallel to the main surface that intersects with the side surface of the substrate and accumulating the raw material liquid on the substrate.

[0006] According to another embodiment, a manufacturing apparatus of a composite electrode is provided. The manufacturing apparatus includes a conveyance mechanism that conveys a band-shaped base material along a conveyance path, a coater that applies a primer solution to the base material, and an electrospinning unit in which a flow direction of a flow path that communicates with a nozzle that ejects a raw material liquid is set to be parallel to a main surface of the base material that intersects with a side surface. The coater applies the primer solution to the base material at a first position of the conveyance path. The electrospinning unit is provided at a second position of the conveyance path that is downstream of the first position of the conveyance path.

[0007] According to the manufacturing method and the manufacturing apparatus described above, a manufacturing method of a composite electrode and a manufacturing apparatus thereof can be provided with high yield and high material efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 FIG. 1 is a perspective view schematically showing an example of a manufacturing apparatus of a composite electrode according to an embodiment.

[0009] Figure 2 FIG. 2 is a schematic cross-sectional view showing an example of a coater included in the manufacturing apparatus of the composite electrode according to the embodiment.

[0010] Figure 3 FIG. 3 is a schematic cross-sectional view showing another example of the coater included in the manufacturing apparatus of the composite electrode according to the embodiment.

[0011] Figure 4 FIG. 4 is a partial perspective view schematically showing an example of an electrospinning machine included in the manufacturing apparatus of the composite electrode according to the embodiment.

[0012] Figure 5 FIG. 5 is a perspective view schematically showing another example of the electrospinning machine included in the manufacturing apparatus of the composite electrode according to the embodiment.

[0013] Figure 6 FIG. 6 is a schematic cross-sectional view showing an example of drying that can be included in the manufacturing method of the composite electrode according to the embodiment.

[0014] Figure 7 FIG. 7 is a schematic cross-sectional view showing an example of rolling that can be included in the manufacturing method of the composite electrode according to the embodiment.

[0015] Figure 8 FIG. 8 is a perspective view for schematically explaining expansion of a fiber when a raw material liquid is ejected based on an electrospinning method according to the related art.

[0016] Figure 9 FIG. 9 is a perspective view for schematically explaining expansion of a fiber when a raw material liquid is ejected based on an electrospinning method according to the related art.

[0017] Figure 10This is a plan view showing an example of the constituent parts of an electrolytic capacitor body manufactured using a composite electrode manufactured by the composite electrode manufacturing method described in the embodiment.

[0018] Figure 11 It is Figure 10 The image shown is an enlarged view of part A.

[0019] Figure 12 This is a partially developed perspective view showing an example of an electrolytic capacitor body including a composite electrode manufactured by the manufacturing method of the composite electrode according to the embodiment.

[0020] Figure 13 This is a perspective view schematically illustrating an example of an electrolytic capacitor comprising a composite electrode manufactured by the manufacturing method of the composite electrode according to the embodiment.

[0021] Figure 14 This is a plan view that schematically shows an example of the constituent parts of a conventional electrolytic capacitor body.

[0022] Figure 15 This is a partially developed perspective view that schematically represents an example of a conventional electrolytic capacitor body.

[0023] Explanation of symbols

[0024] 1: manufacturing device; 3a, 3b: first position; 4a, 4c: second position; 5: third position; 6: fourth position; 8: base material; 10: electrolytic capacitor; 11: anode; 11a: anode foil; 11b: anode terminal; 12: cathode; 12a: cathode foil; 12b: cathode terminal; 13: separator; 14: case; 15: sealing material; 16, 17: electrolytic capacitor body; 18: composite electrode; 18a: electrode foil; 18b: electrode terminal; 18c: insulating fiber film; 19: counter electrode; 19a: counter electrode foil; 19b: counter electrode terminal; 20: unwinder; 21: reel; 30a, 30b: coater; 31: container; 32: metering roll; 33: jet nozzle; 34: primer supply source; 40a, 40b, 40c: electrospinning machine; 41: electrospinning head; 42: raw material liquid supply source; 43: power supply; 44: control section; 45: stage; 46: jig; 47: hinge; 48: belt; 50: drying furnace; 60: press; 61: pressure roll; 70: winder; 71: reel; 81: primer coating film; 82: fiber; 83: insulating fiber film; 83a: expanded diameter; 88: base material; 90: guide roll; 100: conveyance path; 300: primer solution; 341: primer solution storage tank; 342: primer supply driving section; 343: primer supply adjusting section; 345: primer supply piping; 411: head main body; 412: electrospinning nozzle; 412a: nozzle base; 412b: needle portion; 415: storage cavity; 417: flow path; 418: jet outlet; 421: raw material liquid storage section; 422: raw material liquid supply driving section; 423: raw material liquid supply adjusting section; 425: raw material liquid supply piping. DETAILED DESCRIPTION

[0025] The manufacturing method of the embodiment is a method of manufacturing a composite electrode that has a base material having a tape shape and an insulating fiber film provided on the base material. The manufacturing method includes: applying a primer solution on the base material having a tape shape; and forming the insulating fiber film on a main surface of the base material. The charged raw material liquid is jetted in a direction parallel to a main surface of the base material that intersects with a side surface of the base material to be deposited on the base material, thereby forming the insulating fiber film on the main surface of the base material.

[0026] The manufacturing device of the embodiment is a manufacturing device of the above-described composite electrode, and is a device of manufacturing the composite electrode by the above-described manufacturing method. The manufacturing device has a conveyance mechanism, a coater, and an electrospinning unit. The conveyance mechanism conveys the base material having a tape shape along a conveyance path. The coater applies the primer solution on the base material at a first position of the conveyance path. The electrospinning unit is provided at a second position of the conveyance path that is downstream of the first position. The electrospinning unit is a flow path that communicates with a jet outlet that jets the raw material liquid, and a flow direction of the flow path is set to be parallel to a main surface of the base material that intersects with a side surface.

[0027] Hereinafter, the embodiments will be described with reference to the drawings.

[0028] Figure 1 is a perspective view schematically showing an example of a manufacturing apparatus of a composite electrode according to the embodiment. The manufacturing apparatus 1 of the illustrated example is provided with an unwinder 20, a coater 30a, an electrospinning machine 40a including an electrospinning nozzle 412 as an electrospinning unit, a drying furnace 50, a press machine 60, a winder 70, and a plurality of guide rollers 90. In the manufacturing apparatus 1, a conveyance mechanism that conveys the base material 8 along a conveyance path 100 is constituted by the unwinder 20, the winder 70, and the plurality of guide rollers 90.

[0029] The unwinder 20 is provided with a winding shaft 21. The base material 8 is wound in a roll shape on the winding shaft 21. In the unwinder 20, the winding shaft 21 is rotated by a driving member (not shown) such as a motor. The base material 8 wound on the winding shaft 21 is unwound by the rotation. Then, the unwound base material 8 is fed out to the conveyance path 100.

[0030] The winder 70 is provided with a winding shaft 71. In the winder 70, the winding shaft 71 is rotated by a driving member (not shown) such as a motor. Thus, the base material 8 conveyed along the conveyance path 100 is wound in a roll shape by the winding shaft 71.

[0031] In the manufacturing apparatus 1, the base material 8 is conveyed from the unwinder 20 to the winder 70 along the conveyance path 100 by rotating the winding shaft 21 while rotating the winding shaft 71. In addition, the number and arrangement of the guide rollers 90 that guide the base material 8 from the unwinder 20 to the winder 70 are not limited to the illustrated case. Furthermore, the number and arrangement of the bent portions and the return portions in the conveyance path 100 from the unwinder 20 to the winder 70 are not limited to the illustrated case.

[0032] Figure 1 An example of a roll-to-roll apparatus in which the base material 8 fed out from the unwinder 20 continuously passes through each portion of the manufacturing apparatus 1 on the conveyance path 100 and is finally wound by the winder 70 is shown in FIG. 1. However, the embodiment (both the manufacturing method and the manufacturing apparatus) is not limited to this continuous mode. For example, the insulating fibrous film can be formed on the base material 8 in a single sheet mode at a downstream.

[0033] The base material 8 has a tape shape. The tape shape of the base material 8 has, for example, a short side width of 2 mm or more and 6 mm or less. The base material 8 is preferably a conductive foil. The base material 8 is more preferably a conductive foil on the surface of which an oxide coating film that functions as a dielectric layer is chemically formed. In one example, the base material 8 is an aluminum foil covered with an alumina coating film. The base material can have, for example, a thickness of 50 pm or more and 200 pm or less.

[0034] A coater 30a is provided at a first position 3a of the conveyance path 100 of the substrate 8, which is located downstream of the unwinder 20. The coater 30a applies a primer solution 300 to the substrate 8.

[0035] In the illustrated example, a method of applying the primer solution 300 to the substrate 8 by the dipping method at the first position 3a is shown. Figure 2 A primer treatment of the substrate 8 by the dipping method is shown in more detail in.

[0036] Figure 2 is a schematic sectional view showing in more detail the application of the primer solution 300 to the substrate 8 at the first position 3a in the method. The coater 30a provided at the first position 3a is provided with a container 31. The container 31 defines a space through which the substrate 8 passes, and is capable of containing the primer solution 300. In the illustrated example, the coater 30a is also provided with a pair of metering rollers 32. A guide roller 90 is provided at the first position 3a so as to pull the substrate 8 up from the primer solution 300 once it has passed through the primer solution 300. Further, the guide roller 90 is configured so that the substrate 8 pulled up from the primer solution 300 passes between the metering rollers 32.

[0037] At the first position 3a, the substrate 8 is dipped into the primer solution 300 midway through conveyance along the conveyance path 100, whereby the primer solution 300 is applied to the surface of the substrate 8 to form a primer coating film 81 covering the substrate 8. The substrate 8 covered by the primer coating film 81 passes between the pair of metering rollers 32, whereby excess primer solution 300 is removed to form a uniform primer coating film 81.

[0038] The primer solution 300 contains, for example, one or more selected from the group consisting of ethylene glycol and γ-butyrolactone. Further, as the primer solution 300, an organic solvent commonly used as a solvent for electrolyte solutions used in capacitors or condensers can be used. As examples of such an organic solvent, ethylene glycol monomethyl ether, glycerol, N-ethylformamide, and the like can be given.

[0039] The container 31 of the coater 30a is formed of a material resistant to the primer solution 300, such as a synthetic resin material.

[0040] In the manufacturing method and manufacturing apparatus of the embodiment, instead of the above-described dipping method, the primer solution 300 can be applied to the substrate 8 by the spraying method. Figure 3 A primer treatment of the substrate 8 by the spraying method is shown in.

[0041] Figure 3is a schematic cross-sectional view showing the outline of the application of the primer solution 300 to the substrate 8 by the spraying method. In the first position 3b, in addition to the guide roller 90 that defines the conveyance path 100 of the substrate 8, a coater 30b provided with a sprayer having a spray nozzle 33 that sprays the primer solution 300 toward the substrate 8 and a primer supply source 34 is arranged.

[0042] The primer solution 300 is supplied from the primer supply source 34 to the spray nozzle 33. The primer supply source 34 is provided with a primer solution storage tank 341, a primer supply drive section 342, a primer supply adjustment section 343, and a primer supply pipe 345. The primer solution storage tank 341, the primer supply drive section 342, the primer supply adjustment section 343, and the primer supply pipe 345 are each formed of a material that is resistant to the primer solution 300. The sprayer can also include a control section (not shown) that controls the drive of the primer supply drive section 342 and the operation of the primer supply adjustment section 343.

[0043] In the first position 3b, the primer solution 300 is sprayed from the spray nozzle 33 to both the front and back main surfaces of the substrate 8 conveyed along the conveyance path 100, whereby the main surfaces of the substrate 8 are covered with the primer coating film 81. In the illustrated example, the spray nozzle 33 is arranged in such a manner that one of the main surfaces of the substrate 8 is covered with the primer coating film 81 after the other main surface is covered, but the arrangement of the spray nozzle 33 is not limited to the illustrated example. For example, the spray nozzle 33 can be arranged so that both the main surfaces of the substrate 8 are simultaneously exposed to the mist of the primer solution 300.

[0044] In addition, the number of the spray nozzles 33 is not particularly limited, and one or more spray nozzles 33 can be provided for each surface of the substrate 8. Alternatively, a mechanism can be provided that changes the positional relationship between the spray nozzle 33 and the substrate 8 so that, after one or more spray nozzles 33 spray the primer solution 300 to one of the main surfaces of the substrate 8, the one or more spray nozzles 33 spray the primer solution 300 to the other main surface of the substrate 8. Furthermore, it is preferable that the primer solution 300 be sprayed not only to the main surfaces of the substrate 8 but also to the entire surface including the side surface.

[0045] The spray nozzle 33 is preferably formed of a material that is resistant to the primer solution 300, such as stainless steel.

[0046] As for the sprayer, as long as it has a configuration that sprays the primer solution 300 toward the substrate 8, it is not limited to the illustrated configuration provided with the spray nozzle 33 and the like.

[0047] The method of applying the primer solution 300 to the substrate 8 is not limited to the above-described dipping method and the spraying method.

[0048] On the conveyance path 100 of the substrate 8, an electrospinning machine 40a is provided at a second position 4a downstream of the first position 3a (or the first position 3b) at which the primer solution 300 is applied to the substrate 8. The electrospinning machine 40a is provided with electrospinning nozzles 412 arranged so that the nozzle outlets face the side surface of the substrate 8. At the second position 4a, the raw material liquid of the insulating fiber film of the composite electrode is ejected from the electrospinning nozzles 412 in an electrically charged state toward the side surface of the substrate 8 and is accumulated on the substrate 8. By ejecting the electrically charged raw material liquid from the electrospinning nozzles arranged so as to face the side surface of the substrate 8 and causing it to be accumulated on the substrate 8, an insulating fiber film is formed on the main surface of the substrate 8.

[0049] Reference Signs List Figure 4 The formation of the insulating fiber film based on the electrospinning method will be described in detail. Figure 4 is a partial perspective view schematically showing an example of the electrospinning machine provided at the second position. In addition, in Figure 4 , the main surface of the substrate 8 is shown.

[0050] The illustrated electrospinning machine 40b is provided with an electrospinning head 41 as an electrospinning unit and a raw material liquid supply source (supply portion) 42, and is further provided with a power source 43 and a control portion 44.

[0051] The electrospinning head 41 is provided with a head main body 411 and the electrospinning nozzles 412. The electrospinning nozzles 412 are provided to the outer surface of the head main body 411. The head main body 411 and the electrospinning nozzles 412 are each formed of an electrically conductive material.

[0052] In addition, the number of the electrospinning nozzles 412 is not particularly limited, and one or more electrospinning nozzles 412 can be provided. Furthermore, the head main body 411 and the electrospinning nozzles 412 are each preferably formed of a material that is resistant to the raw material liquid described later, for example, stainless steel.

[0053] A receiving cavity 415 is formed in the inside of the head main body 411. The same number of flow paths (nozzle flow paths) 417 as the electrospinning nozzles 412 are formed in the electrospinning head 41, and one corresponding flow path 417 is formed in the inside of each of the electrospinning nozzles 412. One end of each of the flow paths 417 communicates with the receiving cavity 415 and extends from the receiving cavity 415 toward the outside of the head main body 411. Furthermore, a nozzle outlet 418 is formed at the end on the opposite side of the receiving cavity 415 in each of the flow paths 417, and each of the flow paths 417 opens to the outside through the nozzle outlet 418. One corresponding nozzle outlet 418 of the flow path 417 is formed at the tip end protruding from the head main body 411 in each of the electrospinning nozzles 412.

[0054] The electrospinning nozzle 412 can be, for example, a needle-type nozzle. In the illustrated example, the electrospinning nozzle 412 has a nozzle base portion 412a and a needle portion 412b. In the electrospinning nozzle 412, the nozzle base portion 412a is connected to the head body 411, forming a root of the protruding portion that protrudes from the head body 411. Further, in the electrospinning nozzle 412, the needle portion 412b further protrudes from the nozzle base portion 412a toward the outer peripheral side of the electrospinning head 41, forming a protruding end that protrudes from the head body 411. The needle portion 412b has a nozzle outlet 418 formed at the front end thereof. Further, the outer diameter of the needle portion 412b is smaller than the outer diameter of the nozzle base portion 412a. The shape of the electrospinning nozzle 412 is not limited to the illustrated example.

[0055] The raw liquid supply source 42 has a raw liquid storage portion 421, a raw liquid supply drive portion 422, a raw liquid supply adjustment portion 423, and a raw liquid supply pipe 425. The raw liquid storage portion 421, the raw liquid supply drive portion 422, the raw liquid supply adjustment portion 423, and the raw liquid supply pipe 425 each have resistance to raw liquid, and in one example, the raw liquid storage portion 421 and the raw liquid supply pipe 425 are each formed of an insulating material such as fluororesin.

[0056] The raw liquid storage portion 421 is a tank or the like that stores raw liquid. The raw liquid is a liquid obtained by dissolving a high molecular material in a solvent. The high molecular material and the solvent that dissolves the high molecular material are appropriately set in correspondence with the material type of the insulating fiber film formed on the base material 8 or the like.

[0057] The high molecular material is not particularly limited and can be appropriately changed in correspondence with the material of the insulating fiber film to be formed. In one example, as the high molecular material, one or more selected from the group formed of polyamide and polyamide-imide can be used. Further, as the high molecular material, for example, polypropylene, polyethylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, polycarbonate, nylon, and aromatic polyamide or the like can be used.

[0058] The solvent used in the raw liquid can dissolve the high molecular material. The solvent can be appropriately changed in correspondence with the high molecular material to be dissolved. As the solvent, for example, water, methanol, ethanol, isopropanol, acetone, benzene, toluene, N-methyl-2-pyrrolidone (NMP), and dimethylacetamide (DMAc) or the like can be used.

[0059] The raw liquid supply pipe 425 connects between the raw liquid storage portion 421 and the head body 411 of the electrospinning head 41. A flow path of the raw liquid is formed inside the raw liquid supply pipe 425. The raw liquid supply pipe 425 is connected to the head body 411, and the storage cavity 415 communicates with the inside of the raw liquid supply pipe 425.

[0060] The raw material liquid supply driving section 422 supplies the raw material liquid from the raw material liquid storage section 421 to the storage cavity 415 of the head main body 411 through the raw material liquid supply pipe 425 by being driven, etc. In one example, the raw material liquid supply driving section 422 is a pump. Further, in another example, the raw material liquid supply driving section 422 pressurizes the raw material liquid from the raw material liquid storage section 421 to the storage cavity 415 by supplying gas to the raw material liquid storage section 421. The storage cavity 415 can store the raw material liquid supplied through the raw material liquid supply pipe 425.

[0061] The raw material liquid supply adjustment section 423 adjusts the flow rate and pressure, etc. of the raw material liquid supplied to the electrospinning head 41. In one example, the raw material liquid supply adjustment section 423 is provided with a control valve capable of controlling the flow rate and pressure, etc. of the raw material liquid. In this case, the raw material liquid supply adjustment section 423 adjusts the raw material liquid to an appropriate flow rate and pressure, etc. based on the viscosity of the raw material liquid and the configuration of the electrospinning nozzle 412, etc. Further, in one example, the raw material liquid supply adjustment section 423 can switch the supply and stop of the supply of the raw material liquid from the raw material liquid storage section 421 to the electrospinning head 41. In this case, the raw material liquid supply adjustment section 423 is, for example, a switching valve.

[0062] Further, it is not necessarily required to provide the raw material liquid supply driving section 422 and the raw material liquid supply adjustment section 423. In one example, the raw material liquid storage section 421 is provided on the vertically upper side with respect to the head main body 411, and the raw material liquid is supplied from the raw material liquid storage section 421 to the electrospinning head 41 by the gravity. In this case, by adjusting the height difference of the raw material liquid storage section 421 with respect to the head main body 411, it is possible to switch the supply and stop of the supply of the raw material liquid, etc.

[0063] In the embodiment, the electrospinning head 41 provided in the electrospinning machine 40b as the electrospinning unit that ejects the raw material of the insulating fiber film from the ejection port is not limited to the configuration illustrated. Further, in addition to the electrospinning head 41 provided in the electrospinning machine 40b illustrated that is provided with one or more electrospinning nozzles 412, for example, as illustrated in the electrospinning machine 40a, the electrospinning machine can be provided with the electrospinning nozzle that directly supplies the raw material from the raw material liquid supply source 42 as the electrospinning unit, or can be provided with the nozzleless electrospinning head that does not have the electrospinning nozzle although a specific example is not illustrated but is provided with the flow path for the raw material liquid and the ejection port at a portion other than the nozzle. Figure 4 Figure 1 In the embodiment, the electrospinning head 41 provided in the electrospinning machine 40b as the electrospinning unit that ejects the raw material of the insulating fiber film from the ejection port is not limited to the configuration illustrated. Further, in addition to the electrospinning head 41 provided in the electrospinning machine 40b illustrated that is provided with one or more electrospinning nozzles 412, for example, as illustrated in the electrospinning machine 40a, the electrospinning machine can be provided with the electrospinning nozzle that directly supplies the raw material from the raw material liquid supply source 42 as the electrospinning unit, or can be provided with the nozzleless electrospinning head that does not have the electrospinning nozzle although a specific example is not illustrated but is provided with the flow path for the raw material liquid and the ejection port at a portion other than the nozzle.

[0064] ​The power supply 43 can apply voltage to the electric field spinning head 41. By applying voltage to the electric field spinning head 41, a voltage of a predetermined polarity is applied to each of the electric field spinning nozzles 412 via the head body 411. When multiple electric field spinning nozzles 412 are provided, voltages of the same polarity are applied to these electric field spinning nozzles 412. By applying voltage to the electric field spinning head 41 by the power supply 43 as described above, raw material liquid is supplied to the electric field spinning head 41 via the raw material liquid supply adjustment unit 423, thereby charging the raw material liquid to the same polarity as the electric field spinning nozzles 412 (electric field spinning head 41).

[0065] Alternatively, in one example, terminals (not shown) may be provided that are electrically connected to the electric field spinning nozzles 412 respectively, and the power supply 43 applies voltage to the electric field spinning nozzles 412 respectively via the terminals. In this case, it is not necessary to form the head body 411 from a conductive material. Furthermore, the polarity of the voltage applied to the electric field spinning nozzles 412 can be either positive or negative. In the examples shown in the figures, the power supply 43 is a DC power supply, and a positive voltage is applied to the electric field spinning nozzles 412 respectively.

[0066] exist Figure 4 In one example, substrate 8 is grounded. Therefore, when a positive voltage is applied to the electric field spinning nozzle 412, the voltage of substrate 8 to ground is 0V or approximately 0V. In another example, substrate 8 is not grounded. For example, as... Figure 1 As shown in the electric field spinning machine 40a, a voltage of opposite polarity to the electric field spinning nozzle 412 is applied to the guide roller 90 located at the second position 4a via a power source 43 or a power source different from the power source 43. By applying voltage to the guide roller 90, which is made of a conductive material, voltage can be indirectly applied to the substrate 8.

[0067] The electric field spinning nozzle 412 is configured such that the nozzle outlet 418 faces the side of the substrate 8 along its long side. Here, the side facing the nozzle outlet 418 refers to the edge of the substrate 8 along the long side of its strip shape. That is, the side of the substrate 8 referred to here is the surface that intersects with the main surface of the substrate 8. In other words, the side of the substrate 8 is the surface along the thickness direction of the substrate 8. That is, the electric field spinning unit (electric field spinning nozzle 412) is arranged such that the flow direction 419 of the flow path 417 is parallel to the main surface of the substrate 8. In one example, the diameter of the nozzle outlet 418 is 200 μm or more and 500 μm or less.

[0068] In a state where the raw material liquid is supplied to the electrospinning head 41 by the raw material liquid supply source 42, a voltage is applied to the electrospinning head 41 by the power source 43, and thus the raw material liquid is charged to the same polarity as the electrospinning head 41. Alternatively, a voltage is applied to the electrospinning head 41, and the raw material liquid is supplied to the electrospinning head 41, and thus the raw material liquid is charged to the same polarity as the electrospinning head 41. By the raw material liquid being charged to the same polarity as the electrospinning head 41, a potential difference is generated between the raw material liquid of the electrospinning head 41 (the electrospinning nozzle 412) and the base material 8. By the potential difference between the electrospinning head 41 (the electrospinning nozzle 412) and the base material 8, the raw material liquid is ejected toward the base material 8. By the raw material liquid being ejected from the ejection ports 418 of the respective electrospinning nozzles 412 toward the base material 8, the fibers 82 are deposited on the surface of the base material 8, and the insulating fiber film 83 is formed by the deposited fibers 82. That is, the insulating fiber film 83 is formed by the electrospinning method (sometimes also referred to as the electrospinning method and the charge-induced spinning method, etc.).

[0069] In addition, the voltage applied between the electrospinning head 41 and the base material 8, that is, the potential difference between the respective electrospinning nozzles 412 and the base material 8, is adjusted to an appropriate size in correspondence with the kind of the polymer contained in the raw material liquid and the distance of the respective electrospinning nozzles 412 from the base material 8, etc. In one example, a direct current voltage of an arbitrary size of 10 kV or more and 100 kV or less is applied between the respective electrospinning nozzles 412 and the base material 8.

[0070] The raw material liquid ejected from the ejection ports 418 of the electrospinning nozzles 412 moves along the in-plane direction of the main surface of the base material 8 while changing into the fibers 82, and is deposited on the base material 8. That is, the raw material liquid is ejected in a direction parallel to the main surface of the base material, and is deposited on the base material 8 as the fibers 82. Before the raw material liquid ejected from the respective ejection ports 418 of the electrospinning nozzles 412 is deposited on the base material 8 as the fibers 82, the trajectory of the raw material liquid / fibers 82 can be substantially parallel or approximately parallel to the main surface of the base material 8, for example. By ejecting the raw material liquid from the ejection ports 418 of the electrospinning nozzles 412 disposed in a manner that the flow direction 419 of the flow path 417 is parallel to the side surface of the base material 8, the ejection direction of the raw material liquid and the trajectory of the raw material liquid / fibers 82 can be made parallel or approximately parallel to the main surface of the base material 8. In addition, by the potential difference between the charged raw material liquid and the base material 8, the trajectory of the raw material liquid is guided in a direction from the ejection ports 418 toward the base material 8, and thus the influence of gravity on the raw material liquid / fibers 82 can not be a concern.

[0071] The primer coating film 81 is formed by applying the primer solution 300 on the main surface of the substrate 8 at the first position 3a, whereby even if the raw material liquid is ejected toward the direction along the main surface of the substrate 8, the fibers 82 can be accumulated on the main surfaces of the substrate 8 on both sides in a state suitable for the insulating fiber film 83. A part of the fibers 82 exceeds the area of the main surface of the substrate 8 and extends to the outside from the side (across the edge of the substrate 8 on the opposite side in the short side direction) of the substrate 8 on the side opposite to the side facing the ejection port 418 of the electrospinning nozzle 412. The main surface of the substrate 8 is covered with the primer coating film 81, whereby compared to the case where the primer coating film 81 is not present, the extent of the fibers 82 extending can be suppressed to be small. By reducing the extension of the fibers 82, the manufacturing efficiency is improved because there is no need to remove the excess fibers 82. Further, by providing the primer coating film 81 on the main surface of the substrate 8, the fibers 82 can be made to accumulate more on the main surface, and the material efficiency in the manufacturing is improved.

[0072] The fibers 82 are also accumulated on the side of the substrate 8 opposite to the side facing the ejection port 418 of the electrospinning nozzle 412, which corresponds to the face of the edge of the long side of the substrate 8 having a tape shape. On the other hand, on the long side on the side opposite to the side facing the ejection port 418, although the fibers 82 extend as described above, it is difficult for the fibers 82 to be accumulated on the side itself on the opposite side. That is, the side on the opposite side of the substrate 8 is located in a dead angle with respect to the ejection port 418, compared to the side facing the ejection port 418.

[0073] In order to accumulate the fibers 82 on the sides of the substrate 8 along the two long sides on the sides of the tape shape, it is preferable to eject the raw material liquid toward the sides of each long side of the substrate 8 from two directions along the short side direction of the substrate 8. That is, as in the example shown, it is preferable to provide one or more electrospinning nozzles 412 in a manner that the ejection port 418 faces the side of one long side of the substrate 8, and to provide another one or more electrospinning nozzles 412 in a manner that the ejection port 418 faces the side of the other long side of the substrate 8. However, in order to avoid the influence of interference and the like of the electrospinning nozzles 412 to which the same polarity of voltage is applied, it is necessary to take care that the respective ejection ports 418 do not face each other (across the substrate 8). For example, the electrospinning nozzle 412 provided on the one long side of the substrate 8 and the electrospinning nozzle 412 provided on the other long side of the substrate 8 are respectively arranged in a staggered manner along the transport path 100 of the substrate 8.

[0074] The control unit (controller) 44 is, for example, a computer. The control unit 44 includes a processor or integrated circuit (control circuit) such as a CPU (Central Processing Unit), ASIC (Application Specific Integrated Circuit), or FPGA (Field Programmable Gate Array), and a storage medium such as a memory. The control unit 44 may have only one integrated circuit or multiple integrated circuits. The control unit 44 performs processing by executing programs stored in the storage medium. The control unit 44 controls the driving of the raw material supply drive unit 422, the operation of the raw material supply adjustment unit 423, and the output from the power supply 43.

[0075] like Figure 1 As shown, while conveying the substrate 8 along the conveying path 100, raw material liquid / fiber 82 is ejected toward the side of the substrate 8, thereby enabling the continuous formation of an insulating fiber film 83 along the long side direction of the substrate 8. As mentioned above, the manufacturing process may not be continuous. For example, the insulating fiber film 83 may be formed sequentially on the substrate 8 having a predetermined length along its long side. In this case, in order to form the insulating fiber film 83 throughout the length of the substrate 8, the substrate 8 may be movable, or the electric field spinning unit may be moved along the long side direction of the substrate 8. Furthermore, in such a case, the ejection of raw material liquid from an electric field spinning unit facing the side of the substrate 8 along one long side and the ejection of raw material liquid from an electric field spinning unit facing the side of the substrate 8 along the other long side may be performed alternately.

[0076] As with Figure 1 The different continuous roller-to-roll methods shown are referenced. Figure 5 A method for forming an insulating fiber film 83 on a substrate 8 by electric field spinning in a monolithic manner will be described.

[0077] Figure 5is a perspective view schematically showing a method of forming an insulating fiber film by a single sheet method. The electrospinning machine 40c that forms an insulating fiber film by a single sheet method is provided with a belt 48 that conveys the substrate 8 in a state held by the jig 46 and an electrospinning nozzle 412 that ejects a raw material liquid toward the substrate 8. At the 2nd position 4c, the conveying path of the belt 48 is defined by a guide roller 90. The belt 48 is conveyed by a not-shown motor. The jig 46 that is provided with a stage 45 is loaded on the belt 48, and the substrate 8 is held by the jig 46. The electrospinning nozzle 412 is disposed so that the ejection port opposes the side surface of the substrate 8 held by the jig 46 along both side edges. The electrospinning nozzle 412 is supplied with a raw material liquid, but the supply source of the raw material liquid is omitted for simplicity of the drawing. The power supply 43 is disposed so as to be able to apply a voltage of one polarity to the electrospinning nozzle 412 and a voltage of the opposite polarity to the guide roller 90.

[0078] The substrate 8 is cut into a prescribed length in the length direction of the belt shape, and can have a rectangular shape, for example. The dimensions of the rectangular shape are adjusted according to the size of the desired composite electrode, and the length in the long edge direction of the belt shape can be 16 cm or more and 24 cm or less, for example. The portion of the substrate 8 held by the jig 46 becomes a state in which it is shielded by the jig 46, and therefore the fiber 82 does not accumulate in this portion. Therefore, the portion of the substrate 8 held by the jig 46 is cut off when the composite electrode is manufactured, and therefore it is preferable to make the dimensions in the long edge direction of the substrate 8 longer than the long edge length of the electrode foil of the desired composite electrode.

[0079] In the illustrated example, the jig 46 has a configuration that can be opened and closed with the hinge 47 as an axis, and therefore has a mechanism that holds the substrate 8. The configuration of the jig 46 is not limited to the illustrated example, and can have a chuck that holds the substrate 8, for example. The jig 46 preferably has a configuration that can hold the substrate 8 in a state in which the substrate 8 is stretched in a manner that applies a moderate tension to the substrate 8, so that the substrate 8 does not relax.

[0080] A voltage is applied to the electrospinning nozzle 412 by the power supply 43, and the raw material liquid is thereby charged. In the illustrated example, the guide roller 90 is made of an electrically conductive material, and a voltage of the opposite polarity to each electrospinning nozzle 412 is applied to the guide roller 90 by the power supply 43. The belt 48, the stage 45, and the jig 46 are each formed of an electrically conductive material, and a voltage of the opposite polarity to each electrospinning nozzle 412 is indirectly applied to the substrate 8. The guide roller 90 can also be grounded. Figure 5

[0081] As explained previously, the raw material liquid is ejected from the electrospinning nozzle 412 toward the side surface of the substrate 8 by the potential difference between the charged raw material liquid and the substrate 8, and the fiber 82 accumulates on the surface of the substrate 8 covered with the primer solution to form an insulating fiber film.

[0082] ​With the conveyance of the belt 48, the jig 46, which is loaded on the belt 48, and which holds the substrate 8, is moved. That is, the illustrated example corresponds to a manner in which the substrate 8 is movable. Instead of the manner in which the substrate 8 is moved, the electric field spinning nozzle 412 can be moved along the longitudinal direction of the substrate 8.

[0083] By shifting the positional relationship between the substrate 8 and the electric field spinning nozzle 412 along the longitudinal direction of the substrate 8, the insulating fiber film can be formed over the entire length of the longitudinal direction of the substrate 8. The raw material liquid can be simultaneously ejected from each of the electric field spinning nozzles 412, which are disposed on both sides with the substrate 8 interposed therebetween, or the raw material liquid can be alternately ejected from each of the electric field spinning nozzles 412. However, it is to be noted that the ejection ports of each of the electric field spinning nozzles 412 are opposed without the substrate 8 interposed therebetween. Further, from the viewpoint of material efficiency, it is preferable to interrupt the ejection from the electric field spinning nozzle 412 in a state in which the ejection port and the side surface of the substrate 8 are not opposed.

[0084] Alternatively, a plurality of electric field spinning nozzles 412 can be disposed in a manner corresponding to the entire length of the substrate 8, and the raw material liquid can be ejected to form the insulating fiber film without moving either the substrate 8 or the electric field spinning nozzle 412. In this case, for example, by alternately ejecting the raw material liquid from the electric field spinning nozzle 412 disposed on one longitudinal side of the substrate 8 and the raw material liquid from the electric field spinning nozzle 412 disposed on the other longitudinal side, it is possible to avoid interference between the electric field spinning nozzles 412 to which the same polarity of electric field is applied.

[0085] The application of the primer solution 300 at the first position 3a (or the first position 3b) can be performed in a state in which the substrate 8 is held by the jig 46. Further, the drying at the downstream third position 5 can be performed in a state in which the substrate 8 is held by the jig 46. The substrate 8 can be conveyed from the first position 3a to the second position 4c and from the second position 4c to the third position 5 in a state in which the substrate 8 is held by the jig 46.

[0086] In this way, the insulating fiber film can be formed by stacking the fibers 82 on the substrate 8 in a single piece manner in units of each rectangular shape cut to a prescribed length.

[0087] As described above, by applying the primer solution on the substrate 8 and ejecting the raw material liquid toward the side surface of the substrate 8 by the electric field spinning method to stack the insulating fiber film on the main surface of the substrate 8, the composite electrode 18 can be manufactured. Figure 1 A manner in which the drying and the rolling are preferably performed at the third position 5 and the fourth position 6, which are downstream of the second position 4a in the conveyance path 100 of the substrate 8, is shown in FIG. 12.

[0088] In the manufacturing apparatus 1 in which drying is preferably performed, a drying furnace 50 is provided at a third position 5 downstream of the second position 4a. The base material 8 on which the insulating fiber film 83 is formed is transported from the electrospinning machine 40a to the drying furnace 50. Then, the drying furnace 50 dries the primer coating film 81 coated on the surface of the base material 8 passing through the inside thereof and the insulating fiber film 83 formed on the surface of the base material 8. Referring to Figure 6 The drying is described in detail.

[0089] Figure 6 is a schematic cross-sectional view of the drying of the base material 8 on which the primer coating film 81 and the insulating fiber film 83 are formed. The drying furnace 50 provided at the third position 5 can have, for example, an infrared heater 51. The infrared heater 51 generates infrared rays. Then, the infrared heater 51 radiates the generated infrared rays to the insulating fiber film 83 formed on the surface of the base material 8. In the primer solution forming the primer coating film 81 and the insulating fiber film 83, functional groups contained in the organic material and the solvent and the like absorb the infrared rays radiated from the infrared heater 51, whereby the primer coating film 81 and the insulating fiber film 83 are heated, and the solvent contained in the primer solution forming the primer coating film 81 and the insulating fiber film 83 evaporates. Thus, the primer coating film 81 is removed and the amount of the solvent contained in the insulating fiber film 83 is reduced, and the base material 8 and the insulating fiber film 83 are dried.

[0090] Here, it is preferable that the infrared heater 51 radiate infrared light having a wavelength of 10 μm or less corresponding to the maximum radiation intensity to the primer coating film 81 and the insulating fiber film 83. In this case, the temperature of the infrared heater 51 is 17°C (290 K) or higher in a state in which infrared rays are radiated. Here, the functional groups contained in the organic material and the solvent and the like in the insulating fiber film 83 easily absorb infrared rays having a wavelength of 10 μm or less. Therefore, by radiating infrared rays having a wavelength of 10 μm or less corresponding to the maximum radiation intensity, the functional groups contained in the organic material and the solvent and the like in the insulating fiber film 83 more easily absorb the radiated infrared rays, and the solvent contained in the insulating fiber film 83 easily evaporates by heating. Thus, the drying of the insulating fiber film 83 can be more appropriately performed. As the functional groups contained in the solvent of the insulating fiber film 83 that easily absorb infrared rays having a wavelength of 10 μm or less, methyl groups and carbonyl groups and the like can be mentioned.

[0091] Further, in the spectrum of the infrared rays radiated from the infrared ray heater 51, the wavelength corresponding to the maximum radiation intensity is more preferably 4 μm or more and 7 μm or less. By setting the wavelength corresponding to the maximum radiation intensity in the spectrum of the infrared rays radiated to 7 μm or less, the temperature of the infrared ray heater 51 in a state where the infrared rays are radiated is 137°C (410 K) or more. Therefore, by radiating the infrared rays having the spectrum in which the wavelength corresponding to the maximum radiation intensity is 7 μm or less, the organic solvent or the like having a boiling point of 100°C or more also easily evaporates, and the solvent contained in the primer solution forming the primer coating film 81 and the insulating fiber film 83 is more appropriately evaporated. Further, by setting the wavelength corresponding to the maximum radiation intensity in the spectrum of the infrared rays radiated to 4 μm or more, the temperature of the infrared ray heater 51 in a state where the infrared rays are radiated is 451°C (724 K) or less. Therefore, in a state where the infrared rays are radiated, the temperature of the space where the substrate 8 and the insulating fiber film 83 are dried can be effectively prevented from becoming excessively high.

[0092] In addition, the drying of the substrate 8 and the insulating fiber film 83 in the drying furnace 50 is not limited to drying using the infrared rays radiated from the infrared ray heater 51. In some cases, in the drying furnace 50, the substrate 8 and the insulating fiber film 83 can be dried using hot air instead of the infrared rays radiated from the infrared ray heater 51.

[0093] The amount of the solvent contained in the insulating fiber film 83 is reduced by the drying in the drying furnace 50, and thus the amount of the solvent contained in the insulating fiber film 83 in the composite electrode manufactured by the manufacturing device 1 is suppressed to be low. Therefore, the durability of the insulating fiber film 83 of the manufactured composite electrode can be ensured, and the performance of a product using the composite electrode can be ensured.

[0094] For example, in a capacitor using the composite electrode manufactured by the manufacturing method and the manufacturing device according to the embodiment, the amount of the solvent contained in the insulating fiber film 83 functioning as a separator is suppressed to be low, and thus the durability of the insulating fiber film 83 is improved, and the durability of the capacitor is also improved. Further, the amount of the solvent contained in the insulating fiber film 83 is suppressed to be low, and thus the internal resistance of the capacitor is suppressed to be low, and the high output of the capacitor can be achieved. Therefore, the performance of the capacitor can be ensured.

[0095] A press 60 is provided at a fourth position 6 downstream of the third position 5. The press 60 has a pair of press rollers 61. The press 60 is configured to press the insulating fiber film 83 formed on the surface of the substrate 8, and the insulating fiber film 83 is rolled (pressed) by the press, and thus the insulating fiber film 83 is compressed, and the density and the strength of the insulating fiber film 83 can be improved. The details of the press will be described with reference to FIG. 6. Figure 7 The details of the press treatment will be described.

[0096] Figure 7 is a schematic cross-sectional view showing an example of a press that the manufacturing apparatus 1 can have. The press 60 provided at the fourth position 6 on the conveyance path 100 of the base material 8 has a pair of pressure rollers 61. The pair of pressure rollers 61 is driven by, for example, an electric motor or the like. The base material 8 having the insulating fiber film 83 formed on the surface thereof is conveyed along the conveyance path 100 and is sandwiched by the pair of pressure rollers 61. At this time, one of the pressure rollers 61 presses the insulating fiber film 83 and the base material 8 from one side in the thickness direction of the base material 8, and the other of the pressure rollers 61 presses the insulating fiber film 83 and the base material 8 from the other side in the thickness direction of the base material 8. In order to obtain the insulating fiber film 18c having a desired density and thickness as a separator of a composite electrode, the pressing process can be appropriately adjusted.

[0097] In the manufacturing apparatus 1, the press 60 preferably presses the insulating fiber film 83 formed on the surface of the base material 8 at least before the base material 8 is wound by the winding machine 70. In the manufacturing apparatus 1, the press 60 is preferably provided at a position on the conveyance path 100 of the base material 8 that is downstream of the drying furnace 50. By removing the primer solution 300 by drying before pressing by the press 60, it is possible to avoid contamination of the pressure rollers 61 of the press 60. Thus, it is possible to reduce the frequency of cleaning of the pressure rollers 61 or to omit the cleaning process. Furthermore, by drying before pressing, it is possible to more reliably evaporate the solvent of the primer solution 300, the raw material liquid.

[0098] In the manufacturing method of the composite electrode of the above-described embodiment, in a case where a base material having a narrow width is used while the electrospinning method is employed, it is possible to reduce the amount of fibers that protrude outside the area of the main surface of the base material. Reference is made to Figure 8 and Figure 9 for an explanation.

[0099] Figure 8 and Figure 9 schematically show the spread of fibers when the raw material liquid is ejected by the electrospinning method of the prior art method. In Figure 8 and Figure 9In the embodiment, the power source 43 applies a voltage to the base material 88 and between the base material 8 and the electrospinning nozzle 412, the electrospinning nozzle 412 has a nozzle base 412a having a flow path (not shown) intersecting (for example, orthogonal or substantially orthogonal) the flow direction 419 and the base material 88 or the base material 8, and a needle portion 412b, the raw material liquid is supplied from the raw material liquid supply source 42 to the electrospinning nozzle 412 and charged, the charged raw material liquid is ejected from the electrospinning nozzle 412 toward the main surface of the base material 88 and the base material 8, and the raw material liquid is accumulated on the base material 88 and the base material 8 as the fiber 82. When the fiber 82 is accumulated on the main surface of the base material 88 and the base material 8 in a uniform distribution, the spread diameter 83a of the fiber 82 is typically about 40 mm or less. On the other hand, as in the example shown in FIG. 8, if the base material 88 has a rectangular main surface with each side dimension of 50 mm or more, the fiber 82 can be accumulated without extending outward from the base material 88. On the other hand, as in the example shown in FIG. 9, in a case where the short side width of the main surface of the base material 8 is small and the spread diameter 83a of the fiber 82 ejected toward the main surface of the base material 8 exceeds the short side width of the main surface, the fiber 82 extends outward from the area of the main surface of the base material 8. As a specific example, for the base material 8 having a short side width of 6 mm or less, when the spread diameter 83a of the fiber 82 is about 40 mm or more, the fiber 82 extends outward in the short side direction of the base material 8 by 14 mm or more in total. Therefore, the process of removing the excess fiber 82 is added in the manufacturing process, and the material efficiency of the raw material liquid of the fiber 82 is low. On the other hand, as in the example shown in FIG. 8, if the base material 88 has a rectangular main surface with each side dimension of 50 mm or more, the fiber 82 can be accumulated without extending outward from the base material 88. On the other hand, as in the example shown in FIG. 9, in a case where the short side width of the main surface of the base material 8 is small and the spread diameter 83a of the fiber 82 ejected toward the main surface of the base material 8 exceeds the short side width of the main surface, the fiber 82 extends outward from the area of the main surface of the base material 8. As a specific example, for the base material 8 having a short side width of 6 mm or less, when the spread diameter 83a of the fiber 82 is about 40 mm or more, the fiber 82 extends outward in the short side direction of the base material 8 by 14 mm or more in total. Therefore, the process of removing the excess fiber 82 is added in the manufacturing process, and the material efficiency of the raw material liquid of the fiber 82 is low. Figure 8 On the other hand, as in the example shown in FIG. 8, if the base material 88 has a rectangular main surface with each side dimension of 50 mm or more, the fiber 82 can be accumulated without extending outward from the base material 88. On the other hand, as in the example shown in FIG. 9, in a case where the short side width of the main surface of the base material 8 is small and the spread diameter 83a of the fiber 82 ejected toward the main surface of the base material 8 exceeds the short side width of the main surface, the fiber 82 extends outward from the area of the main surface of the base material 8. As a specific example, for the base material 8 having a short side width of 6 mm or less, when the spread diameter 83a of the fiber 82 is about 40 mm or more, the fiber 82 extends outward in the short side direction of the base material 8 by 14 mm or more in total. Therefore, the process of removing the excess fiber 82 is added in the manufacturing process, and the material efficiency of the raw material liquid of the fiber 82 is low. Figure 9 On the other hand, as in the example shown in FIG. 8, if the base material 88 has a rectangular main surface with each side dimension of 50 mm or more, the fiber 82 can be accumulated without extending outward from the base material 88. On the other hand, as in the example shown in FIG. 9, in a case where the short side width of the main surface of the base material 8 is small and the spread diameter 83a of the fiber 82 ejected toward the main surface of the base material 8 exceeds the short side width of the main surface, the fiber 82 extends outward from the area of the main surface of the base material 8. As a specific example, for the base material 8 having a short side width of 6 mm or less, when the spread diameter 83a of the fiber 82 is about 40 mm or more, the fiber 82 extends outward in the short side direction of the base material 8 by 14 mm or more in total. Therefore, the process of removing the excess fiber 82 is added in the manufacturing process, and the material efficiency of the raw material liquid of the fiber 82 is low. On the other hand, as in the example shown in FIG. 8, if the base material 88 has a rectangular main surface with each side dimension of 50 mm or more, the fiber 82 can be accumulated without extending outward from the base material 88. On the other hand, as in the example shown in FIG. 9, in a case where the short side width of the main surface of the base material 8 is small and the spread diameter 83a of the fiber 82 ejected toward the main surface of the base material 8 exceeds the short side width of the main surface, the fiber 82 extends outward from the area of the main surface of the base material 8. As a specific example, for the base material 8 having a short side width of 6 mm or less, when the spread diameter 83a of the fiber 82 is about 40 mm or more, the fiber 82 extends outward in the short side direction of the base material 8 by 14 mm or more in total. Therefore, the process of removing the excess fiber 82 is added in the manufacturing process, and the material efficiency of the raw material liquid of the fiber 82 is low.

[0100] In the manufacturing method and the manufacturing apparatus of the embodiment, when the fiber 82 formed from the raw material liquid is accumulated on the surface of the base material 8 by the electrospinning method, the primer treatment of applying the primer solution 300 on the surface of the base material 8 is performed in advance, and the raw material liquid is ejected toward the side surface of the base material 8 from a direction parallel or substantially parallel to the main surface of the base material 8, not from a direction intersecting the main surface of the base material 8, and the fiber 82 is accumulated on the main surface and the side surface of the base material 8. By this method, the fiber 82 can be efficiently accumulated on the surface of the base material 8, and the amount of the fiber 82 extending from the area of the main surface of the base material 8 can be reduced. Figure 10 and Figure 11 The composite electrode obtained by the manufacturing method and the manufacturing apparatus of the embodiment is shown in FIG. 10.

[0101] Figure 10This is a plan view schematically illustrating an example of a composite electrode and an example of its counter electrode obtained by the manufacturing method and apparatus described above. The composite electrode 18 includes an electrode foil 18a, an electrode terminal 18b, and an insulating fiber membrane 18c formed of fibers 82 and functioning as a separator. The composite electrode 18 has a configuration where the electrode (electrode foil 18a) and the separator (insulating fiber membrane 18c) are integral. The counter electrode 19 includes a counter electrode foil 19a and a counter electrode terminal 19b. The counter electrode 19 is the counter electrode relative to the composite electrode 18. Alternatively, the composite electrode 18 may be a composite anode where the anode and separator are integral, and the counter electrode 19 may be a cathode. Or, the composite electrode 18 may be a composite cathode where the cathode and separator are integral, and the counter electrode 19 may be an anode. The illustrated example is the former combination; in typical specifications, the cathode terminal (counter electrode terminal 19b) is shorter than the anode terminal (electrode terminal 18b) so that the anode terminal and cathode terminal can be visually distinguished.

[0102] The composite electrode 18 is suitable for use as a composite electrode (composite anode or composite cathode) for electrolytic capacitors. The counter electrode 19 can be an electrode (cathode or anode) for electrolytic capacitors.

[0103] Electrode foil 18a and counter electrode foil 19a have a strip shape. Electrode foil 18a and counter electrode foil 19a are preferably conductive foils. More preferably, electrode foil 18a and counter electrode foil 19a are conductive foils on which an oxide coating, functioning as a dielectric layer, is chemically formed on their surface. In one example, each foil is an aluminum foil covered with an aluminum oxide coating. Electrode foil 18a is a reference... Figure 1 The substrate 8, as described above, has, for example, an insulating fiber film 18c formed by the deposition of fibers 82 at position 2a, drying at position 3a, and rolling at position 4a.

[0104] Electrode terminal 18b and counter electrode terminal 19b may, for example, be rod-shaped. Electrode terminal 18b and counter electrode terminal 19b are electrically connected to electrode foil 18a and counter electrode foil 19a, respectively. Each terminal may be electrically connected, for example, by being die-cut and fixed to the foil. The long side of the rod shape of each terminal is oriented, for example, along the short side of the strip shape of the foil. Furthermore, one end of the rod shape of each terminal is aligned with one long side of the strip shape of the foil, and the other end extends from the other long side of the strip shape of the foil. Electrode terminal 18b may be partially covered by an insulating fiber film 18c.

[0105] Figure 11 It is Figure 10 A magnified view of a portion of the composite electrode 18 shown. Figure 10 (Enlarged view of part A). Short side width W of electrode foil 18a FIn a range of 2 mm or more and 6 mm or less. The range in which the insulating fiber film 18c extends in the short side direction of the composite electrode 18 is wider than the short side width W of the electrode foil 18a on both long side sides of the electrode foil 18a F Each of the protruding widths W S . Along both long sides of the electrode foil 18a, the protruding widths W S are 0.2 mm or less. The composite electrode 18 is manufactured by the manufacturing method and the manufacturing apparatus of the embodiment, and thus the protruding widths W S are 0.2 mm or less. In a case where the protruding widths W S are large, the insulating fiber film 18c can more reliably function as a separator that electrically insulates the composite electrode 18 from the counter electrode 19, but from the viewpoint of increasing the electrostatic capacitance per unit volume of the capacitor, it is preferable to make the protruding widths W S on both sides 0.2 mm or less. The protruding widths W S may further be 0.1 mm or less, and specifically, for example, can be 0.06 mm.

[0106] It is preferable to preliminarily nail down the electrode terminal 18b to the base material 8 (electrode foil 18a) before forming the insulating fiber film 18c (insulating fiber film 83) on the surface of the electrode foil 18a. That is, it is desirable to nail down the electrode terminal 18b to the base material 8 before applying the primer solution 300 to the base material 8. By preliminarily nailing down the electrode terminal 18b to the base material 8 before forming the insulating fiber film 18c, it is possible to omit the removal of a part of the insulating fiber film 18c that is generated in a case where the electrode terminal 18b is electrically connected to the base material 8 (electrode foil 18a) later. Furthermore, it is possible to avoid the loss of the function as a separator due to the peeling of the insulating fiber film 18c when the electrode terminal 18b is nailed down later. Also, the surface of the electrode terminal 18b can be partially covered with the insulating fiber film 18c, and thus it is possible to prevent short-circuiting via the electrode terminal 18b. In addition, for a part of the electrode terminal 18b that is not desired to be covered with the insulating fiber film 18c, it is possible to cope with, for example, by removing the excess insulating fiber film 18c later or by performing masking on the part that is not covered.

[0107] The counter electrode foil 19a of the counter electrode 19 can have the same degree of size as the electrode foil 18a of the composite electrode 18.

[0108] By using the composite electrode 18 and the counter electrode 19, it is possible to manufacture an electrolytic capacitor main body that is a main constituent element of an electrolytic capacitor. Figure 12 and Figure 13 Examples of the electrolytic capacitor main body and the electrolytic capacitor are respectively shown in FIGS. 1 to 3.

[0109] Figure 12This is a partial unfolded perspective view of the main body of an electrolytic capacitor using a composite electrode 18 and a counter electrode 19. Figure 13 It is a three-dimensional view that summarizes the electrolytic capacitor body.

[0110] Figure 12 The electrolytic capacitor body 16 shown includes the aforementioned composite electrode 18 and counter electrode 19. The electrolytic capacitor body 16 is manufactured by overlapping the composite electrode 18 and counter electrode 19 such that the ends of the electrode terminals 18b and counter electrode terminals 19b extending from the electrode foil 18a and counter electrode foil 19a, respectively, are oriented in the same direction, and by winding the laminate of the composite electrode 18 and counter electrode 19 such that the electrode terminals 18b and counter electrode terminals 19b extend from the winding end face.

[0111] Figure 13 The electrolytic capacitor 10 shown includes an electrolytic capacitor body (not shown), a housing 14, and a sealing material 15. The electrolytic capacitor body 16 is housed within the housing 14, and the opening of the housing 14 is sealed by the sealing material 15 such that the electrode terminals 18b and the counter electrode terminal 19b are exposed to the outside, thereby constituting the electrolytic capacitor 10. Furthermore, the electrolytic capacitor 10 may further include an electrolyte (not shown) within the housing 14. The electrolyte may, for example, be impregnated with an insulating fiber membrane 18c.

[0112] The electrolytic capacitor 10 can be, for example, an aluminum electrolytic capacitor. In this example of an electrolytic capacitor 10, the electrode foil 18a is an aluminum foil covered with an alumina coating.

[0113] The electrolytic capacitor 10 has a composite electrode 18 manufactured by the manufacturing method or apparatus described in this embodiment, which serves as either the anode or cathode. Therefore, the electrostatic capacitance per unit volume is relatively large. The reasons for this are explained below.

[0114] Figure 14 as well as Figure 15 The diagram shows the components of a conventional electrolytic capacitor. Figure 14 This is a plan view that schematically shows an example of the electrodes and separators included in a conventional electrolytic capacitor. Figure 15 It is a summary of the use Figure 14 A three-dimensional view of the electrolytic capacitor body obtained by the electrodes and separator shown.

[0115] The anode 11 includes a strip-shaped anode foil 11a and an anode terminal 11b. The cathode 12 includes a strip-shaped cathode foil 12a and a cathode terminal 12b. The cathode 12 is the counter electrode opposite to the anode 11. The anode 11 and cathode 12, except that they each lack an insulating fiber membrane, are respectively capable of having... Figure 10 The composite electrode 18 shown has the same configuration or is similar to...Figure 10 The counter electrode 19 is formed in the same manner as the anode 11 and the cathode 12.

[0116] The separator 13 is a member having electrical insulation, such as an insulating paper. The separator 13 can have a belt shape having the same size as the anode 11 and the cathode 12 or a slightly larger size than the anode 11 and the cathode 12.

[0117] The laminate obtained by superimposing the anode 11, one separator 13, the cathode 12, and the other separator 13 in this order is wound so that the anode terminal 11b and the cathode terminal 12b protrude from the winding end surface, thereby producing the electrolytic capacitor main body 17.

[0118] In addition, in Figure 14 and Figure 15 examples of the electrolytic capacitor main body 17 using two separators 13 each having the same length of the long side as the anode 11 and the cathode 12 are illustrated, but various other types of electrolytic capacitor main bodies are being put into practical use.

[0119] In the electrolytic capacitor main body 16 obtained by the manufacturing method and the manufacturing apparatus of the embodiment, unlike the conventional type of electrolytic capacitor main body 17 using the separator 13 formed of an insulating paper or the like independent of the electrode, instead of separately superimposing the separator 13 on the electrode, the insulating fibrous film 18c is formed directly on the electrode foil 18a. The insulating fibrous film 18c can be formed thinner without impairing the function as a separator. Therefore, the electrolytic capacitor main body 16 using the composite electrode 18 can realize the reduction of the volume of the electrolytic capacitor while maintaining the same electrostatic capacitance as the conventional type of electrolytic capacitor main body 17. Alternatively, the electrolytic capacitor main body 16 using the composite electrode 18 can realize the increase of the electrostatic capacitance of the electrolytic capacitor while maintaining the same volume as the conventional type of electrolytic capacitor main body 17. As for this increase of the electrostatic capacitance per unit volume, the amount of the insulating fibrous film 18c protruding from the area of the main surface of the electrode foil 18a is small in the composite electrode 18 manufactured by the manufacturing method and the manufacturing apparatus of the embodiment, which also contributes to this.

[0120] Further, when the electrolytic capacitor main body 16 is produced using the composite electrode 18, the number of components used is smaller compared to the case where the electrolytic capacitor main body 17 is produced using the independent separator 13 on the basis of the electrode, and thus it is expected that the frequency of production of defective products is suppressed and the yield of the manufactured products is improved.

[0121] According to one or more of the above-described embodiments, a method of manufacturing a composite electrode and a device of manufacturing a composite electrode are provided. The composite electrode manufactured by the method and the device has a base material in a belt shape and an insulating fiber film provided on the base material. The method of manufacturing includes: applying a primer solution on the base material; and discharging a charged raw material liquid in a direction parallel to a main surface intersecting a side surface of the base material and depositing the raw material liquid on the base material, thereby forming the insulating fiber film on the main surface of the base material. The device of manufacturing includes: a conveying mechanism that conveys the base material along a conveying path; an applicator that applies the primer solution on the base material at a first position of the conveying path; and an electrospinning unit that is disposed at a second position of the conveying path downstream of the first position, with a flow direction of a flow path communicating with a discharge port of the raw material liquid being parallel to the main surface intersecting the side surface of the base material. According to the method of manufacturing and the device of manufacturing, the composite electrode can be manufactured with a high yield and material efficiency.

[0122] The embodiments of the present application have been described, but these embodiments are suggested as examples and are not intended to limit the scope of the application. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the scope of the application. These embodiments and modifications are included in the scope and spirit of the application, and are included in the scope of the application and equivalents thereof described in the patent claim.

Claims

1. A method of manufacturing a composite electrode, comprising: applying a primer solution to a substrate in a tape shape; and discharging an electrically charged raw material liquid toward a side surface of one of long sides of the substrate in a direction parallel to a main surface intersecting the side surface of the substrate, and discharging an electrically charged raw material liquid toward a side surface of the other of the long sides of the substrate at a position offset in a length direction of the substrate, and accumulating the raw material liquids on the substrate, thereby forming an insulating fiber film on the main surface of the substrate, the composite electrode having the substrate and the insulating fiber film provided on the substrate.

2. The method of manufacturing a composite electrode according to claim 1, wherein a short side width of the tape shape of the substrate is 2 mm or more and 6 mm or less.

3. The method of manufacturing a composite electrode according to claim 1 or 2, wherein the primer solution contains one or more selected from the group consisting of ethylene glycol and γ-butyrolactone.

4. The method of manufacturing a composite electrode according to claim 1 or 2, wherein the primer solution is applied to the substrate by an immersion method.

5. The method of manufacturing a composite electrode according to claim 1 or 2, wherein the primer solution is applied to the substrate by a spraying method.

6. The method of manufacturing a composite electrode according to claim 1 or 2, wherein the tape shape of the substrate has a rectangular shape, and the insulating fiber film is formed on the main surface of the substrate by discharging the electrically charged raw material liquid toward the main surface of the substrate in a direction parallel to the main surface and accumulating the raw material liquid on the substrate in units of the rectangular shape by a single sheet method.

7. The method for manufacturing a composite electrode according to claim 1 or 2, wherein Further comprising: before the primer solution is applied to the substrate, an electrode terminal is fixedly secured to the substrate.

8. An apparatus for manufacturing a composite electrode, comprising: a conveying mechanism that conveys a substrate in a tape shape along a conveying path; an applicator that applies a primer solution to the substrate conveyed along the conveying path; and an electrospinning unit that has a discharge port that discharges a raw material liquid toward the substrate conveyed along the conveying path downstream of a position at which the primer solution is applied by the applicator, one or more of the discharge ports facing a side surface of one of long sides of the substrate being disposed offset in a long side direction of the substrate from another one or more of the discharge ports facing a side surface of the other of the long sides of the substrate, and a flow direction of a flow path communicating with the discharge ports being disposed parallel to a main surface of the substrate intersecting the side surface.

9. The apparatus for manufacturing a composite electrode according to claim 8, wherein Further comprising: a drying furnace disposed at a position downstream of the position of the electrospinning unit in the conveying path, the substrate passing through an interior of the drying furnace.

10. The apparatus for manufacturing a composite electrode according to claim 9, wherein Further comprising: a press disposed at a position downstream of the position of the drying furnace in the conveying path, the insulating fiber film provided on the substrate being rolled by the press.

11. The apparatus for manufacturing a composite electrode according to any one of claims 8 to 10, wherein the applicator has a sprayer that sprays the primer solution toward the substrate.

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