JP2010238425A - Manufacturing method and manufacturing device of battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method and a manufacturing device of a battery having high battery performance by suppressing mixing of air bubbles. <P>SOLUTION: The manufacturing device for manufacturing the battery by sticking laminates 40A, 40B formed by laminating an electrode and a separator and laminating the plurality of laminates, includes: a first holding means 120 negative pressure-holding the back surface with respect to the sticking surface of the first laminate 40B; a second holding means 110 holding the back surface with respect to the sticking surface of the second laminate 40A; and a driving means 150 by approaching the first holding means 120 negative pressure-holding the back surface of the first laminate 40B to the second holding means 110 holding the back surface of the second laminate 40A and laminating the first laminate 40B on the second laminate 40A through sticking. A separator 31 having air permeability is positioned on the back surface of the first laminate 40B, and the first holding means 120 negative pressure-holds the separator 31 at least until the first laminate 40B is laminated on the second laminate 40A through sticking. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a battery manufacturing method and a manufacturing apparatus.

  Bipolar secondary batteries and non-bipolar (stacked) secondary batteries are manufactured by laminating a stacked body in which electrodes and separators are stacked and stacking a plurality of stacked bodies (for example, see Patent Document 1). ).

JP-A-11-204136

  However, when the laminated body in which the electrode and the separator are laminated is bonded and laminated, bubbles may be mixed between the electrode and the separator. The mixed bubbles generate dead space or wrinkles in the separator. Therefore, there is a problem that the movement of ions in the separator is hindered (resistance increases), and the output decreases.

  The present invention has been made in order to solve the problems associated with the above-described prior art, and an object thereof is to provide a battery manufacturing method and a manufacturing apparatus having good battery performance by suppressing the mixing of bubbles. To do.

  The uniform phase of the present invention for achieving the above object is a manufacturing method for manufacturing a battery by laminating a laminated body in which an electrode and a separator are laminated and laminating a plurality of laminated bodies. In the manufacturing method, the first holding body holds the back surface of the bonding surface of the second stacked body while the back surface of the bonding surface of the first stacked body is held by the first holding means. The first laminated body is bonded to the second laminated body and laminated. In addition, a separator having air permeability is positioned on the back surface of the first laminated body, and the first holding means is at least used until the first laminated body is bonded and laminated to the second laminated body. Thus, the separator is held at a negative pressure.

  Another uniform phase of the present invention for achieving the above object is a manufacturing apparatus for manufacturing a battery by laminating and laminating a laminate in which electrodes and separators are laminated. The manufacturing apparatus includes: a first holding unit that can hold a back surface of a bonding surface of a first laminated body under negative pressure; a second holding unit that holds a back surface of a bonding surface of a second laminated body; The first holding means for holding the back surface of the body under negative pressure is brought close to the second holding means for holding the back surface of the second stacked body, and the first stacked body is attached to the second stacked body. Driving means for stacking together. In addition, an air-permeable separator is positioned on the back surface of the first laminated body, and the first holding unit is laminated with at least the first laminated body bonded to the second laminated body. Until the separator is kept under negative pressure.

  According to the method for producing a battery according to the uniform phase of the present invention and the method for producing a battery according to another uniform phase, the separator located on the back surface of the bonding surface of the first laminate has air permeability, and Since the bubbles are discharged through the separator until the first laminated body is bonded to the second laminated body and laminated, the bubbles can be prevented from remaining. Moreover, since the holding | maintenance site | part of a 1st laminated body and a 2nd laminated body is not the outer periphery but the back surface of a bonding surface, it is possible to make a laminated body surface-contact and suppress a bubble remaining in a bonding surface. It is. Thereby, since the generation of dead space and soot due to the mixing of bubbles is reduced, it is possible to avoid a decrease in battery (power generation element) output. Therefore, it is possible to provide a battery manufacturing method and a manufacturing apparatus that can suppress the mixing of bubbles.

It is a perspective view for demonstrating the battery which concerns on embodiment of this invention. It is sectional drawing for demonstrating the battery which concerns on embodiment of this invention. It is a perspective view for demonstrating the assembled battery using the battery shown by FIG. It is the schematic of the vehicle by which the assembled battery shown by FIG. 3 is mounted. It is process drawing for demonstrating the manufacturing method of the battery which concerns on embodiment of this invention. It is a top view for demonstrating the electrode formation process shown by FIG. It is a rear view for demonstrating the electrode formation process shown by FIG. It is sectional drawing regarding line VIII-VIII of FIG. It is a top view for demonstrating the 1st sealing material arrangement | positioning process shown by FIG. It is sectional drawing regarding line XX of FIG. It is the schematic for demonstrating the manufacturing apparatus applied to the assembly process shown by FIG. It is sectional drawing for demonstrating the sub assembly unit formation process shown by FIG. It is sectional drawing for demonstrating the conveyance process shown by FIG. It is sectional drawing for demonstrating the 2nd sealing material arrangement | positioning process shown by FIG. It is sectional drawing for demonstrating the lamination process shown by FIG. It is sectional drawing for demonstrating the repetition of a sub assembly unit formation process-a lamination process. It is sectional drawing for demonstrating the modification 1 which concerns on embodiment of this invention. It is sectional drawing for demonstrating the modification 2 which concerns on embodiment of this invention. It is sectional drawing for demonstrating the modification 3 which concerns on embodiment of this invention. It is sectional drawing for demonstrating the modification 4 which concerns on embodiment of this invention. It is process drawing for demonstrating the modification 4 which concerns on embodiment of this invention. It is the schematic for demonstrating the modification 4 which concerns on embodiment of this invention. It is a chart for demonstrating the micro short circuit test result of the battery which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 and 2 are a perspective view and a cross-sectional view for explaining a battery according to an embodiment of the present invention.

  The battery 10 according to the present embodiment is a bipolar lithium secondary battery, and includes an outer case 14, a battery main body 16 and terminal plates 11 and 12 disposed inside the outer case 14. As will be described later, the battery main body portion 16 is suppressed from being mixed with bubbles, and the battery 10 has good battery performance.

  The exterior case 14 is used to prevent external impacts and environmental degradation, and is formed by joining a part or all of the outer peripheral portion of the sheet material by thermal fusion. The sheet material is composed of a polymer-metal composite laminate film in which metals (including alloys) such as aluminum, stainless steel, nickel, and copper are covered with an insulator such as a polypropylene film from the viewpoint of weight reduction and thermal conductivity. It is preferable.

  The battery body 16 includes a plurality of single cells (battery elements), and includes a bipolar electrode 20, an electrolyte layer 30, a first seal part 25, and a second seal part 27. The bipolar electrode 20 includes a negative electrode 22, a positive electrode 23, and a current collector 21. The positive electrode 23 and the negative electrode 22 are formed on one and the other surfaces of the current collector 21, and the current collector 21 is located between the positive electrode 23 and the negative electrode 22.

The negative electrode 22 has a negative electrode active material made of hard carbon (non-graphitizable carbon material). As the negative electrode active material, for example, a graphite-based carbon material or a lithium-transition metal composite oxide can be used. However, a negative electrode active material composed of carbon and a lithium-transition metal composite oxide is preferable from the viewpoint of capacity and output characteristics. The positive electrode 23 has a positive electrode active material made of LiMn ₂ O ₄ . The positive electrode active material is not limited to LiMn ₂ O ₄ , but it is preferable to apply a lithium-transition metal composite oxide from the viewpoint of capacity and output characteristics. The thicknesses of the positive electrode 23 and the negative electrode 22 are appropriately set in consideration of the intended use of the battery (for example, emphasis on output or energy) and ion conductivity.

  The current collector 21 is formed from a stainless steel foil. As a material for the current collector 21, an aluminum foil, a nickel / aluminum clad material, a copper / aluminum clad material, or a plating material of a combination of these metals can be used.

  The electrolyte layer 30 has a base layer formed by infiltrating a non-aqueous electrolyte into a breathable separator, and a surface layer made of an electrolyte that conducts ions between the separator and the positive electrode 23 or between the separator and the negative electrode 22.

  The separator is formed of porous (porous) PE (polyethylene) and has air permeability. As a material for the separator, other polyolefins such as PP (polypropylene), a laminate having a three-layer structure of PP / PE / PP, polyamide, polyimide, aramid, and non-woven fabric can be used. Nonwoven fabrics are, for example, cotton, rayon, acetate, nylon, and polyester. In addition, although a separator is an insulator, when electrolyte penetrates, it will exhibit ion permeability and electrical conductivity.

  The electrolyte is a gel polymer system and has an electrolytic solution and a host polymer.

The electrolytic solution contains an organic solvent composed of PC (propylene carbonate) and EC (ethylene carbonate), and a lithium salt (LiPF ₆ ) as a supporting salt. As the organic solvent, for example, other cyclic carbonates, chain carbonates such as dimethyl carbonate, and ethers such as tetrahydrofuran can be applied. As the lithium salt, for example, other inorganic acid anion salts and organic acid anion salts such as LiCF ₃ SO ₃ can be applied.

  The host polymer is PVDF-HFP (copolymer of polyvinylidene fluoride and hexafluoropropylene) containing 10% of HFP (hexafluoropropylene) copolymer. As the host polymer, other polymer having no lithium ion conductivity or polymer having ion conductivity (solid polymer electrolyte) can be applied. Other polymers having no lithium ion conductivity are, for example, PAN (polyacrylonitrile) and PMMA (polymethyl methacrylate). Examples of the polymer having ion conductivity include PEO (polyethylene oxide) and PPO (polypropylene oxide).

  The first seal portion 25 is a filling portion that is disposed on one surface of the current collector 21 and extends so as to surround the periphery of the positive electrode 23 and exhibits a good sealing effect, for example, internal mixing of moisture Suppress. The electrolyte layer 30 is disposed so as to cover the positive electrode 23 and the first seal portion 25. The second seal portion 27 is a filling portion that is aligned with the first seal portion 25, is disposed on the other surface of the current collector 21, and extends so as to surround the periphery of the negative electrode 22. An effect is exhibited, for example, internal mixing of moisture is controlled.

  The sealing material constituting the first seal portion 25 and the second seal portion 27 is a one-component thermosetting epoxy resin, but is not particularly limited, and other thermosetting resins (polypropylene, polyethylene, etc.) are applied. It is preferable to select a material that exhibits a good sealing effect in the usage environment according to the intended use.

  The terminal plates 11 and 12 are made of a highly conductive member, extend from the inside of the outer case 14 to the outside, and also serve as electrode tabs for drawing current from the battery body 16. It is also possible to draw an electric current from the battery body 16 by disposing an independent electrode tab and connecting it to the terminal plates 11 and 12 directly or using a lead. The highly conductive member is, for example, aluminum, copper, titanium, nickel, stainless steel, or an alloy thereof.

  The terminal plates 11 and 12 are disposed on the outermost layer (the uppermost layer and the lowermost layer) of the battery body 16 and are configured to cover at least all of the electrode projection surfaces. Therefore, the current extraction portion (current extraction in the surface direction) in the outermost layer is reduced in resistance, and the output of the battery can be increased. Note that the terminal plates 11 and 12 can also be configured by the current collector 21 located in the outermost layer of the battery body 16. It is also possible to arrange a reinforcing plate on the outer side of the terminal plates 11 and 12.

  FIG. 3 is a perspective view for explaining an assembled battery using the battery shown in FIG.

  The battery 10 can be used alone, but can be used in the form of the assembled battery 50. The assembled battery 50 is configured by connecting the batteries 10 in series and / or in parallel and connecting a plurality of the batteries 10, and includes conductive bars 52 and 54. The conductive bars 52 and 54 are connected to terminal plates 11 and 12 extending from the outer case 14 of each battery 10. The connection method is, for example, ultrasonic welding, heat welding, laser welding, rivet, caulking, or electron beam. For example, when the battery 10 is connected, the capacity and voltage can be freely adjusted by appropriately connecting in series or parallel.

  FIG. 4 is a schematic view of a vehicle on which the assembled battery shown in FIG. 3 is mounted.

  The assembled battery 50 itself can be provided as an assembled battery module (large-sized assembled battery) 60 by serializing and / or parallelizing and connecting a plurality of them. Since the assembled battery module 60 can ensure a large output, it can be mounted as a motor driving power source for the vehicle 70. The vehicle is, for example, an electric vehicle, a hybrid electric vehicle, or a train.

  The assembled battery module 60 can perform very fine control such as performing charging control for each built-in exterior case 14 or each assembled battery 50, so that the travel distance per charge can be extended, and the life as an in-vehicle battery can be achieved. It is possible to improve the performance such as prolonging the time.

FIG. 5 is a process diagram for explaining a battery manufacturing method according to an embodiment of the present invention. A battery manufacturing method according to the present embodiment includes an electrode unit forming step for forming an electrode unit; An assembly process for forming a sub-assembly unit (stacked body) in which an electrode unit and a separator are stacked, and forming a bipolar secondary battery (battery body section) in which a plurality of the sub-assembly units are stacked; An assembling process for housing the housing in the exterior case. In the assembly process, air bubbles are prevented from being mixed so as to have good battery performance.

  The electrode unit formation step is divided into an electrode formation step, an electrolyte arrangement step, and a first seal material arrangement step. The assembly process is divided into a sub assembly unit formation process (first laminated body formation process), a transport process, a second sealing material arrangement process, a lamination process, a hot press process, a gel interface formation process, and an initial charging process.

  Next, each step of the electrode unit forming step will be described in detail.

  6 and 7 are a plan view and a rear view for explaining the electrode forming step shown in FIG. 5, and FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG.

  In the electrode formation step, as shown in FIGS. 6 and 7, the positive electrode slurry 23 </ b> A and the negative electrode slurry 22 </ b> A are applied to one and the other surfaces of the current collector 21, respectively. The current collector 21 is, for example, a stainless steel foil having a thickness of 20 μm.

The positive electrode slurry has, for example, a positive electrode active material [85 wt%], a conductive additive [5 wt%], and a binder [10 wt%], and is adjusted to a predetermined viscosity by adding a viscosity adjusting solvent. Yes. The positive electrode active material is LiMn ₂ O ₄ . The conductive auxiliary agent is acetylene black. The binder is PVDF (polyvinylidene fluoride). The viscosity adjusting solvent is NMP (N-methyl-2-pyrrolidone). Carbon black or graphite can also be used as the conductive assistant. The binder and viscosity adjusting solvent are not limited to PVDF and NMP.

  The negative electrode slurry has, for example, a negative electrode active material [90% by weight] and a binder [10% by weight], and is adjusted to a predetermined viscosity by adding a viscosity adjusting solvent. The negative electrode active material is hard carbon. The binder and viscosity adjusting solvent are PVDF and NMP.

  The coating film of the positive electrode slurry and the coating film of the negative electrode slurry are dried using, for example, a vacuum oven. As shown in FIG. 8, the positive electrode 23 made of the positive electrode active material layer and the negative electrode made of the negative electrode active material layer 22 is formed. At this time, NMP is removed by volatilization. The thickness of the positive electrode 23 and the negative electrode 22 is, for example, 30 μm.

  In the electrolyte arrangement step, an electrolyte (not shown) is applied to one and the other surfaces of the current collector 21. The electrolyte application sites are the electrode portions of the positive electrode 23 and the negative electrode 22.

  The electrolyte has, for example, an electrolytic solution [90% by weight] and a host polymer [10% by weight], and has a viscosity suitable for coating by adding a viscosity adjusting solvent. The electrolytic solution contains an organic solvent composed of PC and EC, and a lithium salt as a supporting salt. The lithium salt concentration is 1M. The host polymer is PVDF-HFP containing 10% HFP copolymer. The viscosity adjusting solvent is DMC (dimethyl carbonate). The viscosity adjusting solvent is not limited to DMC.

  FIG. 9 is a plan view for explaining the first sealing material arranging step shown in FIG. 5, and FIG. 10 is a cross-sectional view taken along line XX in FIG.

In the first sealing material arrangement step, the first sealing material 24 is arranged so as to extend around the positive electrode side outer peripheral portion where the current collector 21 is exposed and the positive electrode 23. The first sealing material 24 is a precursor made of a one-component thermosetting epoxy resin (uncured) that constitutes the first sealing portion 25. For example, application using a dispenser is applied to the arrangement of the first sealing material 24. Thereby, the electrode unit 35 is formed. The thickness H ₂ of the first sealing material 24 is set to be larger than the thickness H ₁ of the positive electrode (electrode) 23.

  FIG. 11 is a schematic view for explaining a manufacturing apparatus applied to the assembly process shown in FIG.

  The manufacturing apparatus 100 forms a subassembly unit (stacked body) 40 in which the electrode unit 35 and the separator 31 are stacked, and manufactures a bipolar secondary battery (battery body) in which a plurality of the subassembly units 40 are stacked. And has a mounting table (second holding means) 110, an upper arm (first holding means) 120, and a driving mechanism (driving means) 150. Hereinafter, the sub assembly unit held by the mounting table 110 is referred to by the lower stacked body (second stacked body) 40A, and the sub assembly unit held by the upper arm 120 is referred to as the upper stacked body (first stacked body). Reference is made at 40B. In the first stacking, the upper stacked body 40B held by the upper arm 120 is arranged as it is on the mounting table 110 and becomes the lower stacked body 40A.

  The mounting table 110 is used to hold the back surface 44 of the bonding surface 42 of the lower stacked body 40A and has a flat contact surface 114.

  The upper arm 120 is used to hold the back surface 44 of the upper laminated body 40B by negative pressure, and has a negative pressure holding mechanism 121 and a base portion 128 on which the negative pressure holding mechanism 121 is arranged. The negative pressure holding mechanism 121 includes a suction pad (support portion) 122 that comes into contact with the back surface 44 of the upper laminate 40B, and a negative pressure introduction portion 126 connected to an external negative pressure source. The suction pad 122 is made of a porous material and has a flat contact surface 124. The negative pressure holding mechanism 121 is set to be capable of holding the entire back surface 44 of the upper laminated body 40B by sucking the back surface 44 of the upper laminated body 40B located below the contact surface 124 of the suction pad 122.

  The separator 31 having air permeability is located on the back surface 44 of the upper laminate 40B. Further, the upper arm 120 is set so as to hold the separator 31 under a negative pressure until at least the upper laminated body 40B is bonded and laminated to the lower laminated body 40A.

  The drive mechanism 150 is used to bring the upper arm 120 close to the mounting table 110, and the upper stacked body 40B is bonded to the lower stacked body 40A to be stacked. For example, a multi-joint (multi-axis) type is used. It consists of a robot arm.

  The manufacturing apparatus 100 further includes means (first laminate forming means) for forming the upper laminate 40B by bonding the electrode unit 35 and the separator 31 and laminating them. This means is shared by the upper arm 120 and the drive mechanism 150 in the present embodiment. That is, the upper arm 120 holds the back surface of the bonding surface of the separator 31 with a negative pressure, and the drive mechanism 150 brings the upper arm 120 close to the electrode unit 35 and bonds the separator 31 to the electrode unit 35. And used for lamination.

  As described above, in the manufacturing apparatus 100, the separator 31 positioned on the back surface 44 of the bonding surface 42 of the upper laminate 40B has air permeability and is held by negative pressure, and the upper laminate 40B. Since the bubbles are discharged through the separator 31 until the layer is bonded to the lower laminated body 40A and stacked, it is possible to suppress the remaining of the bubbles. Moreover, since the holding | maintenance site | part of the upper laminated body 40B and the lower laminated body 40A is not the outer periphery but the back surface 44 of the bonding surface 42, the laminated bodies are brought into surface contact and the residual of the bubble in a bonding surface is suppressed. Is possible. Thereby, since the generation of dead space and soot due to the mixing of bubbles is reduced, it is possible to avoid a decrease in battery (power generation element) output. That is, it is possible to provide a battery having good battery performance by suppressing the mixing of bubbles.

  The bonding surface 42 of the lower stacked body 40A and the upper stacked body 40B held by the mounting table 110 and the upper arm 120 is supported in a state where the back surface 44 is supported by flat contact surfaces 114 and 124 and the plane is maintained. Since they are laminated together, it is difficult for wrinkles to occur due to misalignment during adsorption, and it is possible to reliably eliminate bubbles.

  Moreover, when forming the upper laminated body 40B, since bubbles are discharged through the separator 31, it is possible to suppress residual bubbles. That is, it is possible to form the upper laminated body 40B in which mixing of bubbles is suppressed.

  Since the formed upper laminated body 40B is bonded and laminated to the lower laminated body 40A while being maintained at a negative pressure by the upper arm 120, mixing of bubbles during movement (conveyance) is suppressed. Further, since the contact surface 124 of the upper arm 120 does not come into contact with the gel electrolyte applied to the positive electrode 23, handling during transportation is easy.

  In addition, it is also possible to arrange | position the apparatus which forms the upper laminated body 40B by bonding the electrode unit 35 and the separator 31 and laminating | stacking independently.

  Next, each process of the assembly process to which the manufacturing apparatus 100 is applied will be described.

  FIG. 12 is a cross-sectional view for explaining the sub-assembly unit forming step shown in FIG.

  In the sub assembly unit forming step, the electrode unit 35 is disposed on the contact surface 114 made of a flat surface of the mounting table 110, while the rear surface of the air-permeable separator 31 is placed on the upper surface through the contact surface 124 made of a flat surface. A negative pressure is maintained by the arm 120. Then, the upper arm 120 is controlled by the drive mechanism 150, the upper arm 120 is brought close to the electrode unit 35, and the separator 31 is bonded to the electrode unit 35 and laminated. Thereby, the separator 31 is piled up on the positive electrode 23 (electrolyte) and the 1st sealing material 24, and the upper laminated body 40B is formed. The thickness of the separator 31 is 12 μm, for example.

  At this time, the separator 31 bonded and laminated to the electrode unit 35 has air permeability and is held by negative pressure, and when forming the upper laminated body 40B, air bubbles are passed through the separator 31. Since air is discharged, it is possible to suppress residual bubbles. Thereby, the upper laminated body 40B by which mixing of the bubble was suppressed can be formed.

The thickness H ₂ of the first sealing material 24 is set to be larger than the thickness H ₁ of the positive electrode 23 with respect to the stacking direction orthogonal to the bonding surface (see FIG. 10). Protrudes from the positive electrode 23. Therefore, when the separator 31 is bonded to the electrode unit 35 and stacked, after the first sealing material 24 comes into contact with the separator 31, bubbles (gas) try to escape outside.

  At this time, as a result of the first sealing material 24 being extended outward, the distribution of the first sealing material 24 becomes uniform, and it is possible to ensure good and stable sealing performance. For example, since the first sealing material 24 spreads evenly to the edge portion of the current collector 21, short-circuiting at the current collector edge is reduced, and the initial failure rate can be improved. Further, the extension of the first sealing material 24 is in the outward direction (outside in the plane direction) and is prevented from coming into contact with the electrolyte before curing located inside, so that the first sealing material 24 reacts with the electrolyte. By preventing the phenomenon that the resin does not harden, the sealing failure is reduced.

  The back surfaces of the separator 31 and the electrode unit 35 are supported by contact surfaces 114 and 124 that are flat surfaces of the upper arm 120 and the mounting table 110. For this reason, the bonding surfaces of the separator 31 and the electrode unit 35 are bonded and stacked while maintaining a flat surface, so that wrinkles due to misalignment at the time of adsorption are unlikely to occur and bubbles can be reliably eliminated. is there.

  FIG. 13 is a cross-sectional view for explaining the conveying step shown in FIG.

  In the transporting process, the upper arm 120 is controlled by the drive mechanism 150 so that the formed upper laminated body 40B is opposed to the lower laminated body 40A disposed on the contact surface 114 formed of the plane of the mounting table 110. Position. At this time, the separator 31 positioned on the back surface 44 of the upper stacked body 40B is continuously held at a negative pressure by the upper arm 120. Therefore, mixing of bubbles during movement (conveyance) is suppressed. Further, since the contact surface 124 of the upper arm 120 does not come into contact with the gel electrolyte applied to the positive electrode 23, handling during transportation is easy.

  FIG. 14 is a cross-sectional view for explaining the second sealing material arranging step shown in FIG.

  In the second sealing material arranging step, the second sealing material 26 is arranged on the bonding surface 42 (separator 31) of the lower laminated body 40A. At this time, the second sealing material 26 is positioned so as to correspond (overlap) with the arrangement site of the first sealing material 24. The second sealing material 26 is a precursor made of a one-component thermosetting epoxy resin (uncured) that constitutes the second seal portion 27. For example, application using a dispenser is applied to the second sealing material 26.

  In addition, if a 2nd sealing material arrangement | positioning process is before a lamination process, it will not specifically limit to arrange | positioning between a conveyance process and a lamination process.

  FIG. 15 is a cross-sectional view for explaining the stacking step shown in FIG.

  In the stacking step, while holding the back surface 44 of the upper stacked body 40B with a negative pressure by the upper arm 120, the upper stacked body 40B is brought close to the mounting table 110 that holds the back surface 44 of the lower stacked body 40A. The laminated body 40B is bonded and laminated to the lower laminated body 40A. At this time, the air-permeable separator 31 is positioned on the back surface 44 of the upper laminated body 40B, and at least until the upper laminated body 40B is bonded to the lower laminated body 40A and laminated, The separator 31 is maintained at a negative pressure.

  Thus, since the bubbles are discharged through the separator 31 until the upper stacked body 40B is bonded to the lower stacked body 40A and stacked, the remaining of the bubbles can be suppressed. Moreover, since the holding | maintenance site | part of the upper laminated body 40B and the lower laminated body 40A is not the outer periphery but the back surface 44 of the bonding surface 42, the laminated bodies are brought into surface contact and the residual of the bubble in a bonding surface is suppressed. Is possible. Thereby, since the generation of dead space and soot due to the mixing of bubbles is reduced, it is possible to avoid a decrease in battery (power generation element) output. That is, it is possible to provide a battery having good battery performance by suppressing the mixing of bubbles.

  The bonding surface 42 of the lower stacked body 40A and the upper stacked body 40B held by the mounting table 110 and the upper arm 120 is supported in a state where the back surface 44 is supported by flat contact surfaces 114 and 124 and the plane is maintained. Since they are laminated together, it is difficult for wrinkles to occur due to misalignment during adsorption, and it is possible to reliably eliminate bubbles. In the first stacking, the upper stacked body 40B held by the upper arm 120 is arranged as it is on the mounting table 110 and becomes the lower stacked body 40A.

  FIG. 16 is a cross-sectional view for explaining the repetition of the sub-assembly unit forming process to the stacking process.

  When the stacking process is completed, the upper arm 120 releases the upper stacked body 40B and moves up. Thereby, the lower laminated body 40A integrated with the upper laminated body 40B bonded and laminated is held by the mounting table 110. And a sub assembly unit formation process-a lamination process are repeated a predetermined number of times. That is, every time the sub assembly unit forming process to the stacking process are repeated, the number of sub assembly units included in the lower stacked body 40A held by the mounting table 110 increases.

In the hot press step, for example, the lower laminate 40A having a predetermined sub-assembly unit is pressed in a heated state by a hot press machine. The applied pressure is, for example, 0.98 × 10 ⁵ Pa. The heating condition is, for example, 80 ° C. for 1 hour. Thereby, the thickness of the first and second sealing materials 24 and 26 included in the lower laminate 40A is adjusted to a predetermined value (thickness equivalent to the extreme thickness), and the first and second sealing materials 24, The battery body 16 is formed by thermally curing 26 and forming the first and second seal portions 25 and 27.

  In addition, it is also possible to divide a heat press process into the press process which adjusts the thickness of the 1st and 2nd sealing materials 24 and 26, and the heating process which thermosets the 1st and 2nd sealing materials 24 and 26. is there. In this case, when the lower laminated body 40A is configured to be pressed (pressed) by the upper arm 120 of the manufacturing apparatus 100, the stacking process and the pressing process can be continuously performed.

  In the gel interface forming step, by pressurizing the battery body 16 under heating, the electrolyte is infiltrated into the separator 31 included in the battery body, and a gel interface is formed.

  In the initial charging process, the initial charging is performed by the charge / discharge device electrically connected to the battery body 16 to generate bubbles.

  In the assembly process, the battery body 16 is housed in the outer case 14 and the battery 10 (see FIG. 1) is manufactured.

  FIG. 17 is a cross-sectional view for explaining the first modification according to the embodiment of the present invention.

  The size of the separator is not limited to a form larger than the size of the current collector. For example, as shown in FIG. 17, it is possible to make the size of the separator 31A smaller than the size of the current collector 21, and in this case, the sealing material 24A is disposed on the current collector 21 of the lower laminate 40A. Is done.

  The thickness of the sealing material 24 </ b> A is preferably set to be larger than the total thickness of the separator 31 </ b> A, the negative electrode 22, the positive electrode 23, and the current collector 21. Thus, in the laminating step, when the upper laminate 40B is bonded to the lower laminate 40A and laminated, after the sealing material 24A of the lower laminate 40A contacts the current collector 21 of the upper laminate 40B, Air bubbles (gas) try to escape outside. At this time, as a result of the seal material 24A being extended outward, the distribution of the seal material 24A becomes uniform, and it is possible to ensure good and stable sealing performance.

  FIG. 18 is a cross-sectional view for explaining the second modification according to the embodiment of the present invention.

  The mounting table is not limited to a form in which the electrode unit 35 and the lower stacked body 40A are held by their own weight in the sub-assembly unit forming process and the stacking process. For example, a negative pressure holding mechanism 111 and a base 118 on which the negative pressure holding mechanism 111 is disposed can be provided as in the mounting table 110A shown in FIG. The negative pressure holding mechanism 111 has a suction pad (supporting portion) 112 and a negative pressure introducing portion 116 connected to an external negative pressure source. The suction pad 112 is made of a porous material and has a flat contact surface 114.

  Thereby, in the sub assembly unit forming step, the electrode unit 35 can be held at a negative pressure by the mounting table 110A. Accordingly, when the separator 31 is bonded to the electrode unit 35 and stacked, the displacement of the electrode unit 35 is suppressed, so that the stacking accuracy is improved. Further, since the back surface of the electrode unit 35 is maintained at a negative pressure, the smoothness of the bonded surface of the electrode unit 35 is improved.

  On the other hand, in the stacking process, the lower stacked body 40A can be held at a negative pressure by the mounting table 110A. Therefore, when the upper laminated body 40B is bonded to the lower laminated body 40A and laminated, the deviation of the lower laminated body 40A is suppressed, so that the lamination accuracy is improved. Moreover, since the back surface of 40 A of lower laminated bodies is hold | maintained with a negative pressure, the smoothness of the bonding surface of 40 A of lower laminated bodies improves.

  FIG. 19 is a cross-sectional view for explaining a third modification according to the embodiment of the present invention.

  A lamination process is not limited to the form implemented under atmospheric pressure (normal pressure). For example, as shown in FIG. 19, by providing the manufacturing apparatus 100 with the sealing means 130 and the pressure reducing mechanism 140, the stacking process can be performed under reduced pressure. The sealing means 130 is used to seal a space formed between the mounting table 110A holding the lower stacked body 40A and the upper arm 120 holding the upper stacked body 40B. And an upper airtight seal 132, a lower airtight seal 134 and a casing part 136.

  The upper airtight seal 132 is made of an elastic body and is disposed along the outer periphery of the base 128 of the upper arm 120. The lower airtight seal 134 is made of an elastic body and is disposed along the outer periphery of the base 118 of the mounting table 110A. The casing 136 is configured such that a mounting table 110A and an upper arm 120 that respectively hold the lower laminated body 40A and the upper laminated body 40B are slidable.

  Therefore, the upper airtight seal 132 is positioned between the inner surface of the casing portion 136 and the outer periphery of the base portion 128 of the upper arm 120, while the lower airtight seal 134 is disposed between the inner surface of the casing portion 136 and the base portion 118 of the mounting table 110A. When located between the outer periphery, the space between the mounting table 110 </ b> A and the upper arm 120 is sealed. That is, the casing part 136, the upper arm 120, and the mounting table 110A integrally form a hermetic chamber by interposing the upper hermetic seal 132 and the lower hermetic seal 134 therebetween.

  The decompression mechanism 140 is used to decompress the space sealed by the sealing means 130, and includes a decompression piping system 142 and a discharge means 144. The decompression piping system 142 is connected to an external decompression source (not shown) such as a vacuum pump. The discharge means 144 is used to discharge the gas existing in the space and includes an exhaust port disposed in the casing portion 136.

  Accordingly, in the stacking process, when the upper arm 120 descends toward the mounting table 110 while sliding on the inner surface of the casing part 136, the upper airtight seal 132 is attached to the inner surface of the casing part 136 and the outer periphery of the base part 128 of the upper arm 120. On the other hand, the lower airtight seal 134 is located between the inner surface of the casing part 136 and the outer periphery of the base part 118 of the mounting table 110. Therefore, the space between the mounting table 110 and the upper arm 120 is sealed.

  Then, the lowering of the upper arm 120 is continued, and immediately before the lower laminated body 40A and the upper laminated body 40B are bonded and laminated, the pressure reducing mechanism 140 is operated, and the exhaust port 144 and the reduced pressure are arranged in the casing part 136. The sealed space is decompressed by discharging the gas present in the sealed space via the piping system 142.

  The lowering of the upper arm 120 is further continued, and the bonding surface 42 of the upper laminated body 40B held by the upper arm 120 and the bonding surface 42 of the lower laminated body 40A held by the mounting table 110 are brought into contact with each other. Then, the upper laminate 40B and the lower laminate 40A are bonded and laminated.

  In the stacking process according to Modification 3, as described above, the upper stack 40B held by the upper arm 120 and the lower stack 40A held by the mounting table 110 are bonded together under reduced pressure. It is possible to stack, and mixing of bubbles on the bonding surface of the lower stacked body 40A and the upper stacked body 40B can be suppressed.

  20, FIG. 21, and FIG. 22 are cross-sectional views, process drawings, and schematic diagrams for explaining a fourth modification according to the embodiment of the present invention.

  In general, in a bipolar secondary battery, by arranging the seal portion 25 as described above, the electrolyte of the adjacent single cell layer moves over the current collector and is electrically connected through the current collector. This prevents the battery function from stopping due to a liquid junction. However, since the first sealing material 24 constituting the seal portion 25 contacts the separator when the separators are stacked, it is difficult to discharge bubbles remaining between the electrode surface and the separator. On the other hand, in the present embodiment, since air bubbles are discharged through the separator, air bubbles remaining between the electrode surface and the separator are suppressed even when the seal portion 25 (first seal material 24) is present. Is possible. That is, this embodiment is particularly effective for a bipolar secondary battery having a seal portion (seal material) arranged so as to extend around the current collector.

  However, this embodiment can also be applied to a non-bipolar (stacked) secondary battery 10A as shown in FIG.

  The battery body portion 16 of the battery 10A does not have the first and second seal portions 25 and 27, and has a negative electrode 22 so that the negative electrode 22 and the positive electrode 23 face each other with the electrolyte layer 30 therebetween. A non-bipolar electrode having a mold electrode, an electrolyte layer 30 and a positive electrode 23 is laminated in this order. Note that the non-bipolar electrode having the negative electrode 22 includes a negative electrode current collector 21A in which the negative electrode 22 is formed on both surfaces. The non-bipolar electrode having the positive electrode 23 has a positive electrode current collector 21B in which the positive electrode 23 is formed on both surfaces.

  The negative electrode current collector 21A and the positive electrode current collector 21B are connected to a negative electrode current collector plate 17 and a positive electrode current collector plate 18 made of a highly conductive member. The negative electrode current collector plate 17 and the positive electrode current collector plate 18 extend from the inside of the exterior case 14 toward the outside, and also serve as electrode tabs for drawing current from the battery body 16.

  As shown in FIG. 21, the manufacturing method according to Modification 4 includes an electrode unit forming process divided into an electrode forming process and an electrolyte arranging process, a sub-assembly unit forming process, a transporting process, a laminating process, and a gel interface forming process. And an assembly process divided into an initial charging process and an assembling process for accommodating the battery main body in the outer case. In addition, since a hot press process-an assembly process substantially correspond to this Embodiment mentioned above, the description is abbreviate | omitted.

  In the electrode forming step, the positive electrode slurry is applied to both surfaces of the positive electrode current collector 21B. The positive electrode current collector 21B is, for example, an aluminum foil having a thickness of 20 μm. Moreover, negative electrode slurry is apply | coated to both surfaces of the negative electrode collector 21A. The negative electrode current collector 21A is, for example, a copper foil having a thickness of 20 μm.

  In the electrolyte arrangement step, an electrolyte (not shown) is applied to both surfaces of the positive electrode current collector 21B to form a positive electrode unit (non-bipolar electrode). The application site of the electrolyte is the electrode portion of the positive electrode 23. In addition, an electrolyte (not shown) is applied to both surfaces of the negative electrode current collector 21A to form a negative electrode unit (non-bipolar electrode). The application part of the electrolyte is an electrode part of the negative electrode 22.

  In the sub-assembly unit forming step, as shown in FIG. 21, the electrode unit 35A is arranged on the contact surface 114 made of a flat surface of the mounting table 110, while the rear surface of the air-permeable separator 31 is made of a flat surface. Negative pressure is held by the upper arm 120 via the contact surface 124. Then, the upper arm 120 is controlled by the drive mechanism 150, the upper arm 120 is brought close to the electrode unit 35, and the separator 31 is bonded to the electrode unit 35 and laminated. Thereby, separator 31 is piled up on electrolyte and the 1st seal material 24, and upper layered product 40B is formed. The thickness of the separator 31 is 12 μm, for example. A positive electrode unit and a negative electrode unit are alternately applied as the electrode unit 35A.

  In the transporting process, the upper arm 120 is controlled by the drive mechanism 150 so that the formed upper laminated body 40B is opposed to the lower laminated body 40A disposed on the contact surface 114 formed of the plane of the mounting table 110. Position.

  In the stacking step, while holding the back surface 44 of the upper stacked body 40B with a negative pressure by the upper arm 120, the upper stacked body 40B is brought close to the mounting table 110 that holds the back surface 44 of the lower stacked body 40A. The laminated body 40B is bonded and laminated to the lower laminated body 40A.

  FIG. 23 is a chart for explaining the results of the micro short circuit test of the battery according to the embodiment of the present invention.

  In the micro short circuit test, the initial charge was charged at 21 V-0.5 C for 4 hours on the capacity basis estimated from the coating weight of the positive electrode, and then the voltage after 1 hour was measured. The yield (%) per 100 pieces was calculated by taking the appearance defect at the time of completion, those that could not be initially charged, and those with high voltage as the initial failure.

  Example 1 relates to Modification Example 4 and 12 unit cells are stacked by stacking 12 non-bipolar electrodes. Example 2 does not have the first and second sealing materials, and 12 unit cells are stacked by stacking 13 bipolar secondary electrodes. Example 3 is the same as Example 2 except that the first and second sealing materials having a thickness of 50 μm are arranged. The comparative example is formed by manually stacking the separators without holding negative pressure. In addition, the size (mm) of the electrode surface, current collector, and separator in Example 1 is 160 × 128, 160 × 133, and 170 × 140. The sizes (mm) of the electrode surfaces, current collectors, and separators in Examples 2 and 3 and the comparative example are 140 × 110, 160 × 130, and 170 × 140.

  As shown in FIG. 23, the yield of Comparative Examples was 94%, while the yields of Examples 1 to 3 were 97 to 99%, indicating good results.

  As described above, in the method and apparatus for manufacturing a battery according to the present embodiment, bubbles are discharged through the separator until the upper laminate is bonded to the lower laminate and stacked. Residue can be suppressed. Moreover, since the holding | maintenance site | part of an upper laminated body and a lower laminated body is not the outer periphery but the back surface of a bonding surface, it is possible to surface-contact each other and to suppress the bubble remaining in a bonding surface. . Thereby, since the generation of dead space and soot due to the mixing of bubbles is reduced, it is possible to avoid a decrease in battery (power generation element) output. That is, it is possible to provide a battery having good battery performance by suppressing the mixing of bubbles. Therefore, it is possible to provide a battery manufacturing method and a manufacturing apparatus having good battery performance by suppressing the mixing of bubbles.

  Adhering surfaces of the lower laminate and upper laminate, which are held by the mounting table and upper arm, are supported by a flat abutment surface, and the laminate is bonded and laminated while maintaining a flat surface. It is difficult for wrinkles to occur due to time shifts, and it is possible to reliably eliminate bubbles.

  When forming the upper laminate, the bubbles are discharged through the separator, so that the bubbles can be prevented from remaining. That is, it is possible to form an upper laminated body in which mixing of bubbles is suppressed. Further, since the formed upper laminated body is bonded and laminated to the lower laminated body while the negative pressure is continuously maintained by the upper arm, mixing of bubbles during movement (conveyance) is suppressed. Further, since the contact surface of the upper arm does not come into contact with the gel electrolyte applied to the positive electrode, handling during transportation is easy.

  The thickness of the first sealing material is set to be larger than the thickness of the positive electrode in the stacking direction orthogonal to the bonding surface, and the first sealing material protrudes from the positive electrode. Therefore, when the separator is bonded to the electrode unit and stacked, the bubbles (gas) try to escape outside after the first sealing material contacts the separator. At this time, as a result of the first sealing material being extended outward, the distribution of the first sealing material becomes uniform, and it is possible to ensure good and stable sealing performance.

  The mounting table is preferably provided with a negative pressure holding mechanism. In this case, in the sub assembly unit forming step and the laminating step, misalignment between the electrode unit and the lower laminated body is suppressed, so that the laminating accuracy is improved. Moreover, since the negative pressure is maintained on the back surfaces of the electrode unit and the lower laminated body, the smoothness of the bonding surfaces of the electrode unit and the lower laminated body is improved.

  In the stacking step, it is preferable that the upper stacked body held by the upper arm and the lower stacked body held by the mounting table are bonded and stacked under reduced pressure. In this case, mixing of bubbles on the bonding surface of the lower laminate and the upper laminate can be suppressed.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.

  For example, a thermoplastic resin can be applied to the first and second sealing materials. In this case, the first and second sealing materials are plastically deformed by heating to form the first and second sealing portions.

10 Bipolar secondary battery,
10A non-bipolar (stacked) secondary battery,
11,12 terminal plate,
14 exterior case,
16 Battery body (laminate),
17 Negative current collector 18 Positive current collector 20 Bipolar electrode,
21 current collector,
21A negative electrode current collector,
21B positive electrode current collector,
22 negative electrode,
22A negative electrode slurry,
23 positive electrode,
23A positive electrode slurry,
24 first sealing material,
24A sealing material,
25 first seal part,
26 second sealing material,
27 Second seal part,
30 electrolyte layer,
31, 31A separator,
35, 35A electrode unit,
40 Sub-assembly unit (laminate),
40A lower laminate (second laminate),
40B Upper laminate (first laminate),
42 Bonding surface,
44 back,
50 battery packs,
52, 54 conductive bar,
60 battery module,
70 vehicles,
100 manufacturing equipment,
110, 110A mounting table (second holding means),
111 negative pressure holding mechanism,
112 Suction pad (support),
114 abutment surface,
116 negative pressure introduction part,
118 base,
120 upper arm (first holding means),
121 negative pressure holding mechanism,
122 suction pads,
124 abutment surface,
126 negative pressure introduction part,
128 base,
130 sealing means,
132 upper hermetic seal,
134 Lower airtight seal,
136 casing part,
140 decompression mechanism,
142 decompression piping system,
144 Exhaust port (discharge means),
150 drive mechanism (drive means),
H ₁ and H ₂ thickness.

Claims (7)

A production method for producing a battery by laminating a laminate in which an electrode and a separator are laminated, and laminating a plurality of layers,
While holding the back surface of the bonding surface of the first laminated body by the first holding means, the first laminated body is brought close to the second holding means for holding the back surface of the bonding surface of the second laminated body. , Having a laminating step of laminating the first laminate to the second laminate,
A separator having air permeability is located on the back surface of the first laminate, and at least until the first laminate is laminated to the second laminate by the first holding means, The manufacturing method, wherein the separator is held under negative pressure.   2. The manufacturing method according to claim 1, wherein the back surfaces of the first stacked body and the second stacked body are supported by contact surfaces formed by flat surfaces of the first holding means and the second holding means. . Before the laminating step, the electrode and the separator are bonded to each other and further laminated to form the first laminated body, and further includes a first laminated body forming step,
In forming the first laminated body, the separator is bonded to the electrode and stacked while holding the back surface of the bonding surface of the separator at a negative pressure by the first holding means. The manufacturing method of Claim 1 or Claim 2. The electrode is disposed on one surface of the current collector;
Before the first laminated body forming step, further comprising a sealing material arranging step of arranging a sealing material around the electrode on one surface of the current collector,
The manufacturing method according to claim 2, wherein a thickness of the sealing material is greater than a thickness of the electrode with respect to a stacking direction orthogonal to the bonding surface. A manufacturing apparatus for manufacturing a battery by laminating a laminate in which an electrode and a separator are laminated, and laminating a plurality of layers,
First holding means capable of holding negative pressure on the back surface of the bonding surface of the first laminate;
Second holding means for holding the back surface of the bonding surface of the second laminate;
The first holding means for holding negative pressure on the back surface of the first stacked body is brought close to the second holding means for holding the back surface of the second stacked body, and the first stacked body is moved to the second position. Driving means for laminating and laminating the laminate,
A separator having air permeability is located on the back of the first laminate,
The manufacturing apparatus, wherein the first holding unit holds the separator at a negative pressure until at least the first stacked body is bonded to the second stacked body and stacked.   The said 1st holding means and the said 2nd holding means have the contact surface which consists of a plane which contact | abuts the back surface of the bonding surface of a said 1st laminated body and a said 2nd laminated body. The manufacturing apparatus as described. The first laminate forming means for forming the first laminate by laminating and laminating the electrode and the separator,
The first laminated body forming means comprises the first holding means and the driving means,
The first holding means holds the back surface of the bonding surface of the separator under negative pressure,
The said drive means makes the said 1st holding means which hold | maintains the negative pressure of the back surface of the said separator adjoining with the said electrode, The said separator is bonded and laminated | stacked on the said electrode. Or the manufacturing apparatus of Claim 6.

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