JP5494726B2 - Bipolar battery manufacturing method and manufacturing apparatus - Google Patents

Description

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

  In recent years, reduction of carbon dioxide emissions has been strongly desired for environmental protection. In the automobile industry, there is a great expectation for the reduction of carbon dioxide emissions by introducing electric vehicles and hybrid electric vehicles, and attention has been focused on bipolar type (bipolar) batteries as a power source for driving motors, which is the key to their practical use. ing.

  A bipolar battery is composed of a laminate in which current collectors on which a positive electrode and a negative electrode are arranged and separators (electrolyte layers) are alternately arranged, and the laminate is pressurized (see, for example, Patent Document 1). .

JP 9-23003 A

  However, in order to transport the laminate and place it on the press plate for pressurization, handling to remove the laminate or place it on the press plate is necessary from the device for forming the laminate. It is. The handling of the laminated body may cause the current collector and the separator to be displaced and distort the laminated body, thereby deteriorating the flatness of the laminated body. Therefore, there is a problem that it is difficult to uniformly press the laminate.

  The present invention has been made to solve the above-described problems associated with the prior art, and an object of the present invention is to provide a bipolar battery manufacturing method and manufacturing apparatus that can press a laminated body evenly.

In order to achieve the above object, the invention described in claim 1
A bipolar electrode having a current collector, a positive electrode disposed on one surface of the current collector, and a negative electrode disposed on the other surface of the current collector, and an electrolyte layer are alternately disposed on a cradle. , A laminating step for forming a laminate,
A transport step for transporting the cradle in which the laminate is disposed; and
Having a pressing step for heat-pressing the laminate disposed on the cradle in a state of being disposed on the cradle;
In the lamination step,
A support structure to which a holding mechanism having a plurality of clip mechanisms is attached in a direction perpendicular to the surface direction of the bipolar electrode on which the electrolyte layer is disposed is disposed in the perpendicular direction with respect to the cradle. The bipolar electrode gripped by the clip mechanism is sequentially released at the timing when the bipolar electrode gripped by the clip mechanism comes into contact with the cradle. is there.

In order to achieve the above object, the invention according to claim 7 provides:
Bipolar electrodes having a current collector, a positive electrode disposed on one surface of the current collector, and a negative electrode disposed on the other surface of the current collector, and an electrolyte layer are alternately disposed on a cradle And laminating means for forming a laminate,
Conveying means for conveying the cradle in which the laminate is arranged, and
The laminate disposed on the cradle has a pressing means for heat-pressing in a state of being disposed on the cradle,
The laminating means includes
A clip mechanism capable of gripping the bipolar electrode on which the electrolyte layer is disposed;
A holding mechanism having a plurality of the clip mechanisms in a direction perpendicular to the surface direction of the bipolar battery;
A support structure to which the holding mechanism is attached;
A bipolar battery manufacturing apparatus comprising: a Z-axis moving means for moving the support structure relative to the cradle in the vertical direction.

  According to the first aspect of the present invention, in the stacking process for forming the stack, the holding mechanism (clip mechanism) and the cradle move relative to each other in the direction perpendicular to the surface direction of the bipolar battery. . Since the relative movement suppresses the shake of the bipolar battery, the bipolar batteries are stacked with high accuracy. In addition, the formed laminate is transported and subjected to a heat press in a state of being placed on the cradle used to form the laminate, so that it can be removed from the cradle of the laminate or pressed. Handling is not required, and the occurrence of misalignment based on handling can be avoided. Therefore, the laminate is pressed evenly. That is, it is possible to provide a method of manufacturing a bipolar battery that can uniformly press the laminate.

  According to the invention described in claim 7, the stacking means for forming the stacked body relatively moves the holding mechanism (clip mechanism) and the cradle with respect to the direction perpendicular to the surface direction of the bipolar battery. It is possible. Since the relative movement suppresses blurring of the bipolar battery, the bipolar battery is accurately stacked. Further, the formed laminate is transported from the laminating means to the pressing means by the cradle used to form the laminar body, and is heated and pressed in a state of being placed on the cradle. Removal of the body from the cradle and handling for placement on the press means can be eliminated, and the occurrence of misalignment due to handling can be avoided. Therefore, the laminate can be pressed evenly. That is, it is possible to provide a bipolar battery manufacturing apparatus that can press the laminate evenly.

1 is a perspective view for explaining a bipolar battery according to Embodiment 1. FIG. 4 is a cross-sectional view for explaining the bipolar battery according to Embodiment 1. FIG. It is a perspective view for demonstrating the assembled battery using the bipolar battery shown by FIG. It is the schematic of the vehicle by which the assembled battery shown by FIG. 3 is mounted. FIG. 3 is a process diagram for explaining the manufacturing method of the bipolar battery according to the first embodiment. It is a front view for demonstrating the positive electrode which concerns on the electrode formation process shown by FIG. It is a rear view for demonstrating the negative electrode which concerns on the electrode formation process shown by FIG. It is sectional drawing regarding line VIII-VIII of FIG. It is a front view for demonstrating the 1st seal precursor of the seal precursor arrangement | positioning process shown by FIG. It is sectional drawing regarding line XX of FIG. It is a front view for demonstrating the 2nd seal precursor of the seal precursor arrangement | positioning process shown by FIG. It is sectional drawing regarding the line XII-XII of FIG. It is the schematic for demonstrating the clip mechanism of the holding mechanism which concerns on the electrode setting process shown by FIG. It is sectional drawing for demonstrating an electrode setting process. It is the schematic for demonstrating the vacuum processing apparatus which concerns on the vacuum introduction process-vacuum release process shown by FIG. It is the schematic for demonstrating the electrode lamination process shown by FIG. It is sectional drawing for demonstrating the press process shown by FIG. It is sectional drawing for demonstrating the pressurization holding process shown by FIG. FIG. 6 is a schematic diagram for explaining a first modification according to the first embodiment. FIG. 10 is a schematic diagram for explaining a second modification according to the first embodiment. FIG. 10 is a schematic diagram for explaining a third modification according to the first embodiment. FIG. 10 is a schematic diagram for explaining a modification example 4 according to the first embodiment. FIG. 10 is a schematic diagram for explaining a fifth modification according to the first embodiment. FIG. 6 is a process diagram for explaining the manufacturing method of the bipolar battery according to the second embodiment. It is sectional drawing for demonstrating the seal | sticker precursor arrangement | positioning process shown by FIG. It is sectional drawing for demonstrating the electrode setting process shown by FIG.

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

  1 is a cross-sectional view for explaining a bipolar battery according to Embodiment 1, FIG. 2 is a cross-sectional view for explaining the bipolar battery according to Embodiment 1, and FIG. 3 is shown in FIG. FIG. 4 is a schematic view of a vehicle on which the assembled battery shown in FIG. 3 is mounted.

  Bipolar battery 110 according to Embodiment 1 is an electrolyte system, and includes negative electrode 112, positive electrode 113, current collector 111, separator (electrolyte layer) 120, first seal 115, and second seal 117. The current collector 111 is disposed between the positive electrode 113 and the negative electrode 112. The electrolyte layer is formed by soaking the electrolytic solution into the negative electrode surface. The first seal 115 is disposed so as to surround the periphery of the positive electrode 113. The separator 120 is disposed so as to cover the positive electrode 113 and the first seal 115. The second seal 117 is disposed on the separator 120 in alignment with the first seal 115.

  The bipolar battery 110 is in the form of a stacked body 100 of a plurality of single cells (battery elements), and is housed in an outer case 104 for preventing external impact and environmental degradation. Terminal plates 101 and 102 are arranged on the outermost layer (the uppermost layer and the lowermost layer) of the laminate 100.

  The terminal plates 101 and 102 are made of a highly conductive member, and are configured to cover at least all of the outermost electrode projection surfaces of the multilayer body 100. Therefore, the resistance of the current extraction portion in the outermost layer is lowered, and the output of the battery can be increased by reducing the resistance in the current extraction in the surface direction. The highly conductive member is, for example, aluminum, copper, titanium, nickel, stainless steel, or an alloy thereof.

  The terminal plates 101 and 102 extend to the outside of the outer case 104 and also serve as electrode tabs for drawing current from the laminate 100. In addition, it is also possible to draw an electric current from the laminated body 100 by disposing an independent separate electrode tab and connecting it to the terminal plates 101 and 102 directly or using a lead. In addition, the terminal plates 101 and 102 can be configured by the current collector 111 located in the outermost layer of the stacked body 100.

  The outer case 104 is a sheet such as a polymer-metal composite laminate film in which a metal (including an alloy) such as aluminum, stainless steel, nickel, or copper is covered with an insulator such as a polypropylene film from the viewpoint of weight reduction and thermal conductivity. It consists of a material, and part or all of the outer peripheral part is formed by joining by heat sealing | fusion.

  The outer case 104 can be used alone, but can be used, for example, in the form of an assembled battery 130. The assembled battery 130 is configured by connecting a plurality of exterior cases 104 in series and / or in parallel, and includes conductive bars 132 and 134. The conductive bars 132 and 134 are connected to terminal plates 101 and 102 extending from the inside of each outer case 104.

  When connecting and configuring the outer case 104, the capacitance and voltage can be freely adjusted by appropriately connecting in series or parallel. The connection method is, for example, ultrasonic welding, heat welding, laser welding, rivet, caulking, or electron beam.

  The assembled battery 130 itself may be provided in the form of an assembled battery module (large-sized assembled battery) 140 by serializing and / or parallelizing and connecting a plurality of them.

  Since the assembled battery module 140 can ensure a large output, for example, it can be mounted as a power source for driving the motor of the vehicle 145. The vehicle is, for example, an electric vehicle, a hybrid electric vehicle, or a train.

  The assembled battery module 140 can perform very fine control such as charging control for each built-in exterior case 104 or each assembled battery 130, 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 the bipolar battery manufacturing method according to the first embodiment.

  The bipolar battery manufacturing method according to the first embodiment includes an electrode formation step, a seal precursor placement step, an electrode setting step, an electrolyte layer formation step, a vacuum introduction step, an electrode lamination step, a pressing step, a vacuum release step, and pressurization. It has a holding process and a casing process.

  Next, each step will be described in order with reference to FIGS.

  6 is a front view for explaining the positive electrode according to the electrode forming step shown in FIG. 5, FIG. 7 is a rear view for explaining the negative electrode according to the electrode forming step shown in FIG. 5, and FIG. It is sectional drawing regarding line VIII-VIII of FIG.

  In the electrode forming step, first, the positive electrode slurry is adjusted. The positive electrode slurry has a positive electrode active material [85% by weight], a conductive additive [5% by weight], and a binder [10% by weight], and is adjusted to a predetermined viscosity by adding a viscosity adjusting solvent.

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).

  The positive electrode slurry is applied to one surface of a current collector 111 made of stainless steel foil (thickness 20 μm). The coating film of the positive electrode slurry is dried using, for example, a vacuum oven to form the positive electrode 113 made of a positive electrode active material layer having a thickness of 30 μm. At this time, NMP is removed by volatilization.

  Next, the negative electrode slurry is adjusted. The negative electrode slurry has a negative electrode active material [90% by weight] and a binder [10% by weight], and has 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 negative electrode slurry is applied to the other surface of the current collector 111. The coating film of the negative electrode slurry is dried using, for example, a vacuum oven to form the negative electrode 112 made of a negative electrode active material layer having a thickness of 30 μm. At this time, NMP is removed by volatilization.

  As a result, a bipolar electrode in which the positive electrode 113 and the negative electrode 112 are formed on one surface and the other surface of the current collector 111 (bipolar battery 110 in which no electrolyte layer is formed) is obtained.

  The bipolar battery 110 is cut to a size of 330 × 250 (mm). The outer peripheral portions of the positive electrode 113 and the negative electrode 112 are peeled off with a width of 20 mm in order to expose the current collector 111. Thereby, an electrode non-arranged part is formed, and the area (and length) of the current collector 111 is larger than the areas (and length) of the positive electrode 113 and the negative electrode 112. The presence of the electrode non-arranged portion facilitates the arrangement of the first seal precursor 114 and the second seal precursor 116 described later and the gripping by the clip mechanism 153.

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. For example, carbon black or graphite can be used as the conductive assistant. Further, the binder and the viscosity adjusting solvent are not limited to PVDF and NMP.

  The material constituting the current collector 111 is not limited to stainless steel foil, and for example, an aluminum foil, a nickel-aluminum clad material, a copper-aluminum clad material, or a plating material of a combination of these metals may be used. Is possible.

  The negative electrode active material is not limited to hard carbon (non-graphitizable carbon material), and for example, a graphite-based carbon material or a lithium-transition metal composite oxide can be used. A negative electrode active material made of carbon and a lithium-transition metal composite oxide is preferable from the viewpoint of capacity and output characteristics.

  The thicknesses of the positive electrode 113 and the negative electrode 112 are not particularly limited, and are set in consideration of the intended use of the battery (for example, emphasis on output and energy) and ion conductivity.

  9 is a front view for explaining the first seal precursor in the seal precursor arrangement step shown in FIG. 5, FIG. 10 is a sectional view taken along line XX in FIG. 9, and FIG. The front view for demonstrating the 2nd seal precursor of the seal precursor arrangement | positioning process shown, FIG. 12 is sectional drawing regarding the line XII-XII of FIG.

  In the seal precursor arrangement step, first, a first seal precursor (one-component uncured epoxy resin) 114 is arranged on the outer periphery of the positive electrode side where the current collector 111 is exposed. At this time, a non-arranged portion is provided with a width of about 10 mm from the outer peripheral end face. For example, application using a dispenser is applied to the arrangement of the first seal precursor 114.

  Next, the separator 120 is arrange | positioned so that all the positive electrode side surfaces of the electrical power collector 111 may be covered. The separator 120 is made of polyethylene, and the thickness and size thereof are 12 μm and 335 × 255 (mm). That is, the area (and length) of the separator 120 is larger than the area of the current collector 111. Therefore, in the case of being laminated, it is possible to suppress contact between the outer peripheral portions of the adjacent current collectors 111, and it is possible to improve insulation.

  Thereafter, a second seal precursor (one-component uncured epoxy resin) 116 is disposed on the separator 120. At this time, the second seal precursor 116 is positioned so as to face (overlap) the arrangement site of the first seal precursor 114. For example, application using a dispenser is applied to the arrangement of the second seal precursor 116.

  The constituent material of the first seal precursor 114 and the second seal precursor 116 is not limited to the one-component uncured epoxy resin, and a material that exhibits a good sealing effect in the usage environment is appropriately selected according to the application. can do. For example, other thermosetting resins (polypropylene, polyethylene, etc.) and thermoplastic resins can be applied.

  The constituent material of the separator 120 is not limited to polyethylene, and other polyolefins such as polypropylene, resin materials such as polyamide and polyimide can be applied.

  FIG. 13 is a schematic view for explaining a clip mechanism of the holding mechanism according to the electrode setting step shown in FIG. 5, and FIG. 14 is a cross-sectional view for explaining the electrode setting step.

  In the electrode setting step, six bipolar batteries 110 (110A to 110F) are set in the electrode stocker (stacking means) 150 with the negative electrode surface facing up.

  Note that the configurations of the bipolar batteries 110A and 110F held at the uppermost and lowermost positions are appropriately set in consideration of productivity and subsequent processes. In Embodiment 1, the bipolar battery 110A held at the top does not have the negative electrode 112, and the bipolar battery 110F held at the bottom has only the negative electrode 112 and the current collector 111, The positive electrode 113, the first seal precursor 114, the second seal precursor 116, and the separator 120 are not disposed.

  The electrode stocker (stacking means) 150 includes a holding mechanism, a support structure 154, a cradle 156, and a control unit (not shown).

  The holding mechanism has six clip mechanisms 153 that can grip two opposing portions of the outer peripheral portion of the bipolar battery 110, and can set six bipolar batteries 110. The part of the bipolar battery 110 held by the clip mechanism 153 is located in a region having a width of about 10 mm from the outer peripheral end face, and the first seal precursor 114 and the second seal precursor 116 are not arranged. It is a part.

  The clip mechanism 153 is based on elastic force and includes lower and upper arms 191 and 193, a guide block 195, a movable block 197 and a drive rod 198.

  The lower arm 191 has a distal end portion on which the bipolar battery 110 is placed and a base portion that extends from the distal end portion via a lower stepped portion 192. The upper arm 193 has a tip portion that presses the bipolar battery 110, an intermediate portion that extends from the tip portion via the first upward inclined portion, and a base portion that extends from the intermediate portion via the second upward inclined portion 194. . The lower and upper arms 191 and 192 are elastically biased so as to be close to each other, for example, by an elastic member (not shown) made of a spring.

  The guide block 195 is fixed to the base of the lower arm 191 and has a through hole 196. The movable block 197 is disposed between the guide block 195 and the lower step 192 of the lower arm 191, and is elastically biased toward the guide block 195 by, for example, an elastic member (not shown) made of a spring. Yes.

  The drive rod 198 is disposed so as to freely reciprocate, and the diameter of the drive rod 198 is set so as to pass through the through hole 196 of the guide block 195. Accordingly, the tip of the drive rod 198 protruding from the through hole 196 presses the movable block 197 and moves it toward the lower step 192 of the lower arm 191.

  Since the movable block 197 is in contact with the second upper inclined portion 194 of the upper arm 193, the movement of the movable block 197 causes the upper arm 193 to rise.

  That is, when the drive rod 198 is protruded, the tip portions of the lower and upper arms 191 and 192 are separated from each other, so that the bipolar battery 110 can be disposed or released (released). . On the other hand, when the drive rod 198 is retracted, the tip portions of the lower and upper arms 191 and 192 are close to each other, so that the bipolar battery 110 can be gripped. The clip mechanism 153 is not particularly limited to the above configuration as long as the bipolar battery 110 can be gripped.

  The support structure 154 has a frame shape and a holding mechanism attached to avoid interference when the bipolar battery 110 is set. The holding mechanism is attached in a direction (Z-axis direction) perpendicular to the surface direction (XY-axis direction) of the bipolar battery 110 so that the bipolar batteries 110 are aligned and do not contact each other.

  The support structure 154 is provided with Z-axis moving means (not shown) for moving in a vertical direction toward the cradle 156. Since the Z-axis moving means moves the support structure 154 relative to the cradle 156, the installation space can be used effectively. In particular, since the electrode stocker 150 is disposed inside a vacuum processing apparatus 160 (described later), the equipment cost can be reduced by downsizing the vacuum processing apparatus 160.

When the Z-axis moving means is disposed on the support structure 154, the structure of the cradle 156 and its surroundings can be simplified. However, the Z-axis moving means is disposed on the cradle 156 and supports the cradle 156. it is also possible to relatively move with respect to structure 154. In this case, the support structure 154 is fixed, and the cradle 156 moves inside the support structure 154, so that the support structure 154 can be prevented from shaking. Further, the Z-axis moving means can be arranged in the clip mechanism 153.

Cradle 156, formed of a laminate 100 of the bipolar battery 110, are used for conveying and pressing.

  The stacked body 100 sequentially mounts the bipolar batteries 110, that is, a bipolar having a positive electrode 113 disposed on one surface of the current collector 111 and a negative electrode 112 disposed on the other surface of the current collector 111. It is formed by alternately arranging the mold electrodes and the separators 120 constituting the electrolyte layer on the cradle.

  The conveying means is, for example, a belt conveyor, and is used to move the cradle 156 to the next process. Therefore, it is possible to transport the laminated body 100 to the next process in a state where it is disposed on the cradle 156. This eliminates the need for handling for removing the laminate 100 from the cradle 156 during transport, and avoids the occurrence of misalignment. The conveying means is not limited to a belt conveyor, and can be configured as a separate body from the receiving table 156.

  The outer periphery of the contact surface of the cradle 156 with respect to the bottom surface of the stacked body 100 is surrounded by a recess, and the area (and length) of the contact surface is smaller than the area (and length) of the current collector 111. .

  The control unit is used to sequentially stack the bipolar battery 110 held by the clip mechanism 153 on the cradle 156, and for example, controls the holding and release of the bipolar battery 110 by the clip mechanism 153.

  In the electrolyte layer forming step, 1 ml of the electrolyte is applied to the negative electrodes 112 of the five bipolar batteries 110B to 110F, excluding the bipolar battery 110A held at the top, using, for example, a micropipette. It is infiltrated by putting it on the surface.

The electrolytic solution contains an organic solvent composed of PC (propylene carbonate) and EC (ethylene carbonate), a lithium salt (LiPF ₆ ) as a supporting salt, and a small amount of a surfactant. The lithium salt concentration is 1M.

The organic solvent is not particularly limited to PC and EC, and for example, other cyclic carbonates, chain carbonates such as dimethyl carbonate, and ethers such as tetrahydrofuran can be applied. The lithium salt is not particularly limited to LiPF ₆ , and other inorganic acid anion salts and organic acid anion salts such as LiCF ₃ SO ₃ can be applied.

  15 is a schematic diagram for explaining the vacuum processing apparatus according to the vacuum introduction process to the vacuum release process shown in FIG. 5, and FIG. 16 is a schematic diagram for explaining the electrode stacking process shown in FIG. 17 is a cross-sectional view for explaining the pressing step shown in FIG. 5, and FIG. 18 is a cross-sectional view for explaining the pressurizing and holding step shown in FIG.

  The vacuum processing apparatus 160 includes a vacuum unit 162, a press unit 172, and a control unit 178.

  The vacuum unit 162 includes a vacuum chamber 163, a vacuum pump 164, and a piping system 165. The vacuum chamber 163 has a detachable (openable) lid, and a fixed base on which the electrode stocker 150 and the press means 172 are arranged. The vacuum pump 164 is, for example, a centrifugal type, and is used to bring the inside of the vacuum chamber 163 into a vacuum state. The piping system 165 is used to connect the vacuum pump 164 and the vacuum chamber 163, and a leak valve (not shown) is arranged.

  The press unit 172 includes a base plate 174, a press plate 176 that is arranged to be close to and away from the base plate 174, a lower heating unit 175, and an upper heating unit 177.

  On the base plate 174, a cradle 156 that is transported in a state where the stacked body 100 is disposed is placed. The cradle 156 functions as a lower press plate. Therefore, handling for removing the laminated body 100 from the cradle 156 becomes unnecessary during pressing, and the occurrence of deviation can be avoided.

  The press plate 176 is used to press the stacked body of the bipolar battery 110 in cooperation with the cradle 156.

  The outer periphery of the contact surface of the press plate 176 with respect to the upper surface of the laminate 100 is surrounded by a recess, and the area (and length) of the contact surface is smaller than the area (and length) of the current collector 111.

  The lower heating means 175 and the upper heating means 177 have, for example, resistance heating elements, are disposed inside the base plate 174 and the press plate 176, and are used to raise the temperature of the base plate 174 and the press plate 176. Is done.

  The controller 178 controls the temperature of the press plate 176 and the pressure of the press plate 176 and the temperature of the lower heating means 175 and the upper heating means 177 to perform an appropriate heat press on the stacked body of the bipolar battery 110 under vacuum. Used for.

  One of the lower heating means 175 and the upper heating means 177 can be omitted, or the lower heating means 175 and the upper heating means 177 can be arranged outside the base plate 174 and the press plate 176. Furthermore, the base plate 174 can be omitted as appropriate.

  Next, a vacuum introduction process to a vacuum release process to which the vacuum processing apparatus 160 is applied will be sequentially described.

  In the vacuum introduction process, the lid of the vacuum chamber 163 is removed, and the electrode stocker 150 holding the bipolar battery 110 is disposed at the base of the vacuum chamber 163. When the lid of the vacuum chamber 163 is attached and the vacuum chamber 163 is sealed, the vacuum pump 164 is operated and the inside of the vacuum chamber 163 is evacuated.

  In the electrode stacking step, the support structure 154 of the electrode stocker 150 is moved toward the cradle 156 under vacuum by the Z-axis moving means. That is, the holding mechanism (clip mechanism 153) and the cradle 156 are relatively moved by the Z-axis moving unit in the direction perpendicular to the surface direction of the bipolar battery 110. Since the relative movement suppresses the shake of the bipolar battery 110, the bipolar battery 110 is stacked with high accuracy.

  On the other hand, when the bipolar battery 110 held by the clip mechanism 153 of the support structure 154 comes into contact with the cradle 156, the drive rod 198 of the clip mechanism 153 is controlled to cancel the holding of the bipolar battery 110. .

  Then, by continuing the movement of the support structure 154 with respect to the cradle 156, the bipolar batteries 110F to 110A are sequentially stacked (see FIG. 16).

  As described above, blurring of the bipolar battery 110 is suppressed, and the bipolar batteries can be stacked with high accuracy. Therefore, the occurrence of displacement between the bipolar electrode and the electrolyte layer constituting the bipolar battery 110 is suppressed and the occurrence of an internal short circuit can be avoided, so that the occurrence of defective products can be reduced.

  In addition, since the layers are stacked under vacuum, mixing of bubbles with respect to the stack interface between the electrode and the electrolyte layer is suppressed. Therefore, the movement of ions during use is not harmed and the battery resistance does not increase, so that a high output density can be achieved. That is, since a bipolar battery in which the mixing of bubbles is suppressed is obtained, the movement of ions during use is not harmed, and the battery resistance does not increase, so that a high output density can be achieved.

  The laminated body 100 is conveyed to a press process in the state arrange | positioned at the receiving stand 156. FIG. This eliminates the need for handling for removing the laminate 100 from the cradle 156 during transport, and avoids the occurrence of misalignment.

  In the pressing step, the cradle 156 of the electrode stocker 150 is disposed on the base plate 174 (see FIG. 17). At this time, the pedestal 156 holds the stacked body 100 of the bipolar batteries 110 formed by the electrode stacking process.

The press plate 176 descends toward the cradle 156 and cooperates with the cradle 156 functioning as the other press plate, thereby pressing the laminate 100 and applying a surface pressure of 1.0 × 10 ⁵ Pa.

  Since the laminated body 100 is not removed from the cradle 156 after the formation, and the occurrence of deviation is suppressed, the laminated body 100 is pressed evenly. The laminate 100 is pressed by the contact surface of the press plate 176 and the cradle 156 that is smaller than the area of the current collector 111.

  On the other hand, the lower heating unit 175 and the upper heating unit 177 are operated to heat the stacked body of the cradle 156 and the bipolar battery 110 via the base plate 174 and the press plate 176. The laminated body of the bipolar battery 110 is heated to 80 ° C., which is the curing temperature of the one-component uncured epoxy resin constituting the first seal precursor 114 and the second seal precursor 116.

The first seal precursor 114 and the second seal precursor are held for 1 hour under the pressing conditions (surface pressure 1.0 × 10 ⁵ Pa and 80 ° C.) while maintaining the vacuum state in the electrode lamination step. 116 hardens | cures, the 1st seal | sticker 115 and the 2nd seal | sticker 117 of predetermined thickness are formed, and the laminated body 100 is obtained.

The press pressure is not limited to 1.0 × 10 ⁵ Pa, and is, for example, 1.0 × 10 ⁴ Pa to 1.0 × 10 ⁶ Pa in consideration of physical properties such as strength of the constituent material of the laminate 100. It is preferable. The pressing temperature is not limited to 80 ° C., and the physical properties such as the heat resistance of the electrolytic solution and the curing temperature of the first seal precursor 114 (first seal 115) and the second seal precursor 116 (second seal 117). In consideration, for example, it is preferably 60 ° C to 150 ° C.

  In addition, since a press is laminated | stacked under a vacuum, it can suppress that purge gas mixes into a lamination | stacking interface. Further, by controlling the distance between the cradle 156 and the press plate 176 at the time of pressing and setting the thickness of the laminate 100 to a predetermined value, it is possible to reduce the volume and the electrolyte resistance. Since it is a heating press, the first seal precursor 114 and the second seal precursor 116 are cured simultaneously, so that the manufacturing process can be shortened.

  In the vacuum release process, the vacuum pump 164 is stopped, and the vacuum state of the vacuum chamber 163 is released by opening the leak valve. The press plate 176 is raised and the lid of the vacuum chamber 163 is removed. The cradle 156 of the electrode stocker 150 arranged on the base plate 174 is taken out while holding the stacked body 100. Further, parts of the electrode stocker 150 other than the cradle 156 are also taken out.

  In the pressurizing and holding step, the pressurized state of the heat-pressed laminate 100 is held by the pressurizing and holding unit 183 until it is transferred to the casing step (see FIG. 18).

  The pressure holding unit 183 includes a support plate 184, a pressing plate 185, and a weight 186. The stacked body 100 is disposed on the support plate 184. The pressing plate 185 is disposed on the upper surface of the stacked body 100. The weight 186 is disposed on the upper surface of the pressing plate 185.

  Therefore, the weight 186 can generate a pressing force for maintaining the pressurized state of the stacked body 100 by its own weight. The weight of the weight 186 is appropriately set in consideration of physical properties such as the press pressure and the strength of the constituent material of the laminate 100.

  In the casing process, the laminated body 100 in which the pressurized state is maintained is accommodated in the exterior case 104 (see FIGS. 1 and 2). The exterior case 104 is formed, for example, by joining outer peripheral portions of a sheet-shaped exterior material. The exterior material is, for example, a polymer-metal composite laminate film in which a metal (including an alloy) such as aluminum, stainless steel, nickel, or copper is coated with an insulator such as a polypropylene film. Thermal fusion such as impulse sealing, ultrasonic fusion, and high frequency fusion is applied.

  FIG. 19 is a schematic diagram for explaining the first modification according to the first embodiment.

  In order to shorten the time of the pressing process, it is also possible to arrange an oven 182 for preheating the electrode stocker 150. In this case, the bipolar battery 110 and the cradle 156 held by the electrode stocker 150 are heated by heating means (not shown) of the oven 182. The heating means is not particularly limited, and is, for example, an infrared halogen lamp or a resistance heating element.

  In addition, by incorporating the heating means 182 in the cradle 156, the cradle 156 and the stacked body 100 placed on the cradle 156 can be heated by the heating means 182. Further, the cradle 156 may be disposed on the base plate 174 and incorporated in the electrode stocker 150 after being heated by the lower heating means 175.

  Furthermore, it is possible to shorten the time of the pressing process by operating the lower heating means 175 and the upper heating means 177 and preheating the base plate 174 and the press plate 176 before the cradle 156 is arranged. is there.

  FIG. 20 is a schematic diagram for explaining a second modification according to the first embodiment.

  The laminated body 100 is not limited to the structure directly pressed by the cradle 156 and the press plate 176. For example, the sheet-like elastic bodies 189 and 190 can be disposed on the cradle 156 and the press plate 176.

  In this case, the elastic bodies 189 and 190 are positioned so as to face the laminate 100, have an abutment surface for pressing the laminate 100, and the area (and length) of the abutment surface is The current collector 111 is set to be smaller than the area (and length) of the current collector 111. In addition, since the cradle 156 and the press plate 176 do not have an abutting surface, the hollow part arrange | positioned so that the outer periphery of the cradle 156 and the press plate 176 may be unnecessary.

  FIG. 21 is a schematic diagram for explaining the third modification according to the first embodiment.

  The pressing force in the pressurizing and holding unit 183 is not limited to using the weight of the weight 186, and the clamping mechanisms 187 and 188 can also be used. The clamp mechanisms 187 and 188 have a pair of arms, and by pressing the outer surfaces of the support plate 184 and the pressing plate 185 with their tip portions, it is possible to generate a pressing force. For driving the arm, for example, urging by an elastic member such as a spring or screw tightening by a fastening member can be used.

  FIG. 22 is a schematic diagram for explaining the fourth modification according to the first embodiment.

  It is also possible to arrange a correction means for correcting the positional deviation at the time of relative movement of the bipolar battery 110 in the electrode stocker 150. The correcting means includes a position sensor 158 arranged on the support structure 154 and an XY axis moving means (not shown) arranged on the cradle 156.

  The position sensor 158 is disposed at a position corresponding to the four sides of the bipolar battery 110 on the upper surface of the support structure 154 and constitutes a two-dimensional position detection unit. Therefore, the position sensor 158 can detect a positional shift during the relative movement of the bipolar battery 110, that is, during the movement of the bipolar battery 110 toward the cradle 156. As the two-dimensional position detection means, for example, a CCD (solid-state imaging device) image sensor can be used. In this case, the two-dimensional position detection means can be configured by disposing at one of the four corners on the upper surface of the support structure 154.

  The XY axis moving means is used to move the cradle 156 in the surface direction of the bipolar battery 110.

  Therefore, when the position sensor 158 detects a positional shift in the relative movement of the bipolar battery 110, the position in the surface direction of the cradle 156 is adjusted by controlling the XY axis moving means. It is possible to further improve the stacking accuracy. Further, since the cradle 156 is irrelevant to the holding mechanism, the movement of the cradle 156 does not affect the position of the bipolar battery 110 and the positional deviation can be easily adjusted.

  Note that the XY-axis moving means is not limited to being disposed on the cradle 156, and by placing it on the holding mechanism, the structure of the cradle 156 and the vicinity thereof can be simplified. Further, the Z-axis moving means can be arranged in the clip mechanism 153. By making one axial direction of the XY axis moving means coincide with the moving direction of the cradle 156 to the next process, the XY axis moving means can also be used as a moving mechanism for the cradle 156 to the next process. It is.

  FIG. 23 is a schematic diagram for explaining the fifth modification according to the first embodiment.

  In order to improve the output density of the battery, it is possible to divide the pressing process into two parts, a first pressing process and a second pressing process, and to insert an initial charging process for removing bubbles generated by the initial charging. The initial charging condition is, for example, 4 hours at 21 V-0.5 C on a capacity basis estimated from the coating weight of the positive electrode.

  In this case, the charge / discharge device 180 is disposed in the vacuum processing device 160. The charging / discharging device 180 is configured to be electrically connectable to the stacked body 100 via the base plate 174 and the press plate 176 of the press means 172.

The pressing condition of the first pressing step is holding for 60 seconds at a surface pressure of 1.0 × 10 ⁵ Pa and a normal temperature. The pressing condition of the second pressing step is holding for 1 hour at a surface pressure of 1.0 × 10 ⁵ Pa and 80 ° C. The press conditions of the first press step are not particularly limited, and are set so that the first seal precursor and the second seal precursor are not cured in consideration of the press conditions of the second press step.

  As described above, Embodiment 1 can provide a method for manufacturing an electrolyte-based bipolar battery that can press the laminate evenly.

  In addition, it is also possible to laminate | stack alternately with a bipolar type electrode (bipolar type | mold battery with no electrolyte layer arrange | positioned) by making an electrolyte layer (separator) into a different body. In this case, the holding mechanism holds the electrolyte layer and the bipolar electrode alternately, and is aligned with respect to the plane direction of the bipolar electrode and the electrolyte layer so that the bipolar electrode and the electrolyte layer are aligned and do not contact each other. And attached to the support structure 154 in a perpendicular direction.

  In addition, the electrode setting process is preferably performed in the atmosphere in consideration of the installation process and the like, but may be performed in a vacuum as necessary.

  Next, a second embodiment will be described. In the following, members having the same functions as those in the first embodiment are denoted by similar reference numerals, and the description thereof is omitted to avoid duplication.

  FIG. 24 is a process diagram for explaining the manufacturing method of the bipolar battery according to the second embodiment.

  The bipolar battery according to Embodiment 2 is a gel polymer electrolyte system, and the manufacturing method thereof includes an electrode formation process, an electrolyte layer formation process, a seal precursor formation process, an electrode setting process, a vacuum introduction process, an electrode lamination process, It has a press process, a vacuum release process, a pressure holding process, and a casing process.

  Next, each step will be described sequentially. FIG. 25 is a cross-sectional view for explaining the seal precursor arranging step shown in FIG. 24, and FIG. 26 is a cross-sectional view for explaining the electrode setting step shown in FIG.

  In the electrode formation step, as in the first embodiment, a bipolar electrode in which the positive electrode 213 and the negative electrode 212 are formed on one surface and the other surface of the current collector 211 (bipolar type in which no electrolyte layer is formed) A battery 210) is obtained.

  In the electrolyte layer forming step, an electrolyte is applied to the electrode portions of the positive electrode 213 and the negative electrode 212.

  The electrolyte has 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 (propylene carbonate) and EC (ethylene carbonate), and a lithium salt (LiPF ₆ ) as a supporting salt. The lithium salt concentration is 1M.

  The host polymer is PVDF-HFP (copolymer of polyvinylidene fluoride and hexafluoropropylene) containing 10% of HFP (hexafluoropropylene) copolymer. The viscosity adjusting solvent is DMC (dimethyl carbonate).

  The electrolyte applied to the electrode part is dried and the DMC is volatilized to form gel polymer electrolyte layers 218 and 219 on the positive electrode 213 and the negative electrode 212.

  The host polymer is not limited to PVDF-HFP, and other polymers that do not have lithium ion conductivity or polymers that have ion conductivity (solid polymer electrolyte) can also 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 viscosity adjusting solvent is not limited to DMC.

  In the seal precursor forming step, the first seal precursor 214, the separator 220, and the second seal precursor 216 are arranged as in the first embodiment.

  In the electrode setting step, an electrode stocker 250 having a holding mechanism (clip mechanism 253), a support structure 154, a cradle 156, a position sensor 158, and a control unit (not shown) is used as in the first embodiment. In addition, six bipolar batteries 210 (210A to 210F) are set in the electrode stocker 250 with the negative electrode face up. Note that the bipolar battery 210F held at the lowest level does not include the gel polymer electrolyte layer 218 on the positive electrode side, the first seal precursor 214, the second seal precursor 216, and the separator 220.

  In the vacuum introduction process, by using a vacuum processing apparatus having a vacuum unit, a press unit, and a control unit, the electrode stocker holding the bipolar battery 210 is connected to the base of the vacuum chamber as in the first embodiment. When placed in the vacuum chamber, the inside of the vacuum chamber is maintained in a vacuum state.

  In the electrode stacking step, the holding mechanism (clip mechanism 253) and the cradle 256 are relatively moved by a Z-axis moving unit in a direction perpendicular to the surface direction of the bipolar battery 210 under vacuum. Since the relative movement suppresses the shake of the bipolar battery 210, the bipolar battery 210 is stacked with high accuracy.

  On the other hand, when the bipolar battery 210 held by the clip mechanism 253 of the support structure 254 comes into contact with the cradle 256, the drive rod of the clip mechanism 253 is controlled to cancel the holding of the bipolar battery 210.

  Then, by continuing the movement of the support structure 254 with respect to the cradle 256, the bipolar batteries 210F to 210A are sequentially stacked.

  In addition, the laminated body 200 is conveyed to a press process in the state arrange | positioned at the receiving stand 256. FIG. This eliminates the need for handling for removing the laminate 200 from the cradle 256 during transport, and avoids the occurrence of misalignment.

  In the pressing process, the cradle 256 of the electrode stocker 250 is disposed on the base plate. At this time, the stacked body 200 of the bipolar battery 210 formed by the electrode stacking process is held on the cradle 256.

The laminated body 200 is heated and pressed by a press plate and a cradle 256 in a state where a vacuum state is maintained. The pressing conditions are 1 hour holding at a surface pressure of 1.0 × 10 ⁵ Pa and 80 ° C. Thereby, the first seal precursor and the second seal precursor are cured, and the first seal and the second seal having a predetermined thickness are formed. Further, the gel polymer electrolyte layers 218 and 219 are plasticized and have a predetermined thickness.

  As described above, the laminated body 200 is not removed from the cradle 256 after formation, and the occurrence of deviation is suppressed. Therefore, the laminate 200 is pressed evenly.

  In addition, since the pressing is performed under heating, the first seal precursor 214 and the second seal precursor 216 are cured and the gel polymer electrolyte layers 218 and 219 are completed at the same time, so that the manufacturing process can be shortened. it can.

  In the vacuum releasing step, the vacuum state of the vacuum chamber is released and the stacked body 200 is taken out.

  In the pressurization and holding process, the pressurized state of the laminated body 200 that has been hot-pressed is held until it is transferred to the casing process.

  In the casing process, the laminated body 200 in which the pressurized state is maintained is accommodated in the outer case 104 (see FIGS. 1 and 2).

  As described above, Embodiment 2 can provide a manufacturing method and manufacturing apparatus for a gel polymer electrolyte bipolar battery that can uniformly press the laminate.

  Since the gel polymer electrolyte layers 218 and 219 are of a thermoplastic type in which an electrolytic solution is held in a polymer skeleton, liquid leakage can be prevented and a liquid crystal can be prevented to form a highly reliable bipolar battery. is there. The gel polymer electrolyte is not limited to a thermoplastic type, and a thermosetting type can also be applied. In this case as well, liquid leakage is prevented by curing the electrolyte layer with a hot press, and a liquid junction can be prevented.

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

  For example, the first to fifth modifications according to the first embodiment can be applied to the second embodiment.

100 laminates,
101,102 terminal plate,
104 exterior case,
110 (110A to 110F) bipolar battery,
111 current collector,
112 negative electrode,
113 positive electrode,
114 first seal precursor,
115 first seal,
116 second seal precursor,
117 second seal,
120 separator,
130 battery pack,
132,134 conductive bar,
140 assembled battery module,
145 vehicles,
150 electrode stocker,
153 clip mechanism,
154 support structure,
156 cradle,
158 position sensor,
160 vacuum processing equipment,
162 vacuum means,
163 vacuum chamber,
164 vacuum pump,
165 piping system,
172 pressing means,
174 base plate,
175 Lower heating means,
176 press plate,
177 Upper heating means,
178 controller,
180 charging / discharging device,
182 oven,
183 pressure holding means,
184 support plate,
185 pressing plate,
186 weight,
187,188 Clamp mechanism,
189, 190 elastic body,
191 Lower arm,
192 Lower step,
193 Upper arm,
194 second upward inclined portion,
195 guide block,
196 through hole,
197 movable block,
198 Drive rod,
200 laminates,
210 bipolar battery,
210 (210A to 210F) bipolar battery,
211 current collector,
212 negative electrode,
213 positive electrode,
214 first seal precursor;
216 second seal precursor;
218, 219 Gel polymer electrolyte layer,
220 separator,
250 electrode stocker,
253 clip mechanism,
254 support structure,
256 cradle.

Claims (13)

A bipolar electrode having a current collector, a positive electrode disposed on one surface of the current collector, and a negative electrode disposed on the other surface of the current collector, and an electrolyte layer are alternately disposed on a cradle. , A laminating step for forming a laminate,
A transport step for transporting the cradle in which the laminate is disposed; and
Having a pressing step for heat-pressing the laminate disposed on the cradle in a state of being disposed on the cradle;
In the lamination step,
A support structure to which a holding mechanism having a plurality of clip mechanisms is attached in a direction perpendicular to the surface direction of the bipolar electrode on which the electrolyte layer is disposed is disposed in the perpendicular direction with respect to the cradle. The bipolar electrode gripped by the clip mechanism is sequentially released at the timing when the bipolar electrode gripped by the clip mechanism comes into contact with the cradle.   In the pressing step, the laminated body is pressurized by bringing the cradle and a press plate facing the laminated body close to each other, and also by heating the cradle and / or the press plate. The method of manufacturing a bipolar battery according to claim 1, wherein the temperature is raised.   The area of the current collector is larger than the areas of the positive electrode and the negative electrode, and the area of the separator of the electrolyte layer is larger than the area of the current collector. The manufacturing method of the bipolar battery of description.   The bipolar battery manufacturing method according to claim 1, further comprising a heating step for heating the cradle before being conveyed to the pressing step.   A pressurizing and holding step for holding a pressurized state of the heat-pressed laminate, and a casing step for accommodating the laminate in a pressurized state in an exterior case. The manufacturing method of the bipolar battery of any one of Claims 1-4.   The bipolar battery according to any one of claims 1 to 5, wherein in the stacking step, the stacked body is formed under vacuum, and in the pressing step, heat pressing is performed under vacuum. Method. Bipolar electrodes having a current collector, a positive electrode disposed on one surface of the current collector, and a negative electrode disposed on the other surface of the current collector, and an electrolyte layer are alternately disposed on a cradle And laminating means for forming a laminate,
Conveying means for conveying the cradle in which the laminate is arranged, and
The laminate disposed on the cradle has a pressing means for heat-pressing in a state of being disposed on the cradle,
The laminating means includes
A clip mechanism capable of gripping the bipolar electrode on which the electrolyte layer is disposed;
A holding mechanism having a plurality of the clip mechanisms in a direction perpendicular to the surface direction of the bipolar battery;
A support structure to which the holding mechanism is attached;
A bipolar battery manufacturing apparatus, comprising: Z-axis moving means for moving the support structure relative to the cradle in the vertical direction. The pressing means is disposed so as to be close to and away from the cradle conveyed by the conveying means, and presses the press plate facing the laminated body, and the cradle and / or the press plate. The bipolar battery manufacturing apparatus according to claim 7, further comprising: a heating unit.   The said cradle and the said press plate have a contact surface for pressing the said laminated body, The area of the said contact surface is smaller than the area of the said collector. Item 9. The bipolar battery manufacturing apparatus according to Item 8.   It has a sheet-like elastic body arranged on the cradle and the press plate, and the elastic body is positioned so as to face the laminated body and has a contact surface for pressing the laminated body. The bipolar battery manufacturing apparatus according to claim 7, wherein an area of the contact surface is smaller than an area of the current collector.   The bipolar battery manufacturing apparatus according to claim 7, further comprising a heating unit configured to heat the cradle before being conveyed to the pressing unit. The bipolar battery manufacturing apparatus according to any one of claims 7 to 11 , further comprising a pressurizing and holding unit configured to hold a pressurized state of the laminate that has been heated and pressed by the pressing unit. . The bipolar battery manufacturing apparatus according to any one of claims 7 to 12 , further comprising vacuum means for operatively holding the laminating means and the pressing means under vacuum.