Battery manufacturing device and battery manufacturing method

Abstract

The present invention reduces the damage incurred to a member used to mitigate the collapse of an end part of a laminate. This battery manufacturing device (1) press-forms laminates (10) in which a positive electrode layer, a negative electrode layer, and a solid electrolyte layer interposed between the positive electrode layer and the negative electrode layer are laminated. The battery manufacturing device (1) comprises: press pins (31, 32) that apply pressure, to a plurality of the laminates (10) laminated in the thickness direction of the laminates (10), in the thickness direction; and a sandwich plate (6) that has a sandwiched part at least partially sandwiched by two of the laminates (10), a peripheral part provided spaced apart from and in the vicinity of the sandwiched part, and an intermediate part connected to the sandwiched part and the peripheral part and having a lower stiffness than the sandwiched part.

Description

Battery manufacturing apparatus and battery manufacturing method

[0001] The present invention relates to a battery manufacturing apparatus and the like.

[0002] An all-solid-state battery includes a laminate in which a positive electrode layer, a solid electrolyte layer, and a negative electrode layer are stacked. Each layer in such a laminate is formed from a powder material and is molded by pressure. In the pressure molding of a laminate, multiple laminates are stacked in the thickness direction of the laminate, and these laminates are then pressed in the thickness direction in order to shorten the takt time, etc. When a highly compressible powder material is pressure molded, the powder material is significantly deformed, which can cause the edges of each layer in the laminate to crumble. In particular, the larger the area of ​​the stacking surface in the laminate, the more likely the edges of each layer to crumble.

[0003] In response to this, for example, Patent Document 1 describes that when an all-solid-state battery in which laminates and conductive rigid bodies are alternately stacked is pressed, breakage due to rolling is suppressed in the laminates sandwiched between the conductive rigid bodies. The conductive rigid bodies function as a conductive material incorporated in the all-solid-state battery, and are preferably formed from stainless steel that plastically deforms when pressed so as to absorb the pressure acting on the laminates.

[0004] Japanese Patent Application Publication No. 2022-139307

[0005] However, in an apparatus for stacking and pressurizing a plurality of laminates as described above, if a member such as a conductive rigid body is used to mitigate collapse at the edge of the laminate, the member will become unreusable if it undergoes plastic deformation. Also, if the member is a highly rigid member that does not undergo plastic deformation, it can be reused, but because it is highly rigid, stress caused by pressure is concentrated at the edge of the member, which can cause damage to the member.

[0006] An object of one aspect of the present invention is to reduce damage to members used to mitigate collapse of the edges of a laminate.

[0007] In order to solve the above problems, one embodiment of the present invention provides a battery manufacturing apparatus that pressure-forms a laminate comprising a first electrode layer, a second electrode layer having a polarity opposite to that of the first electrode layer, and a solid electrolyte layer interposed between the first electrode layer and the second electrode layer, and includes a pressure unit that presses a plurality of the laminates stacked in the thickness direction of the laminate, a clamping unit having at least a portion sandwiched between two of the laminates, a peripheral portion that is provided around the clamping portion and spaced apart from the clamping portion, and a clamping plate that is connected to the clamping portion and the peripheral portion and has an intermediate portion with lower rigidity than the clamping portion.

[0008] In order to solve the above-mentioned problems, one embodiment of the present invention provides a battery manufacturing method that pressure-forms a laminate that includes a first electrode layer, a second electrode layer having a polarity opposite to that of the first electrode layer, and a solid electrolyte layer interposed between the first electrode layer and the second electrode layer, and includes a stacking step of alternately stacking the laminate, a clamping portion at least a portion of which is sandwiched between the two laminates, a peripheral portion that is provided around the clamping portion and spaced apart from the clamping portion, and a clamping plate that is connected to the clamping portion and the peripheral portion and has an intermediate portion with lower rigidity than the clamping portion, in a thickness direction of the laminate; and a pressurizing step of pressurizing the stacked laminate and the clamping plate in the thickness direction.

[0009] According to one aspect of the present invention, damage to members used to mitigate collapse of the edge of a laminate can be reduced.

[0010] 5 is a side view showing the configuration of a laminate constituting an all-solid-state battery manufactured by a battery manufacturing apparatus according to an embodiment of the present invention. FIG. 6 is a front view showing the configuration of the battery manufacturing apparatus. FIG. 7 is a plan view showing the configuration of a handling robot provided in the battery manufacturing apparatus. FIG. 8 is a plan view showing the configuration of a supply machine provided in the battery manufacturing apparatus. FIG. 9 is a plan view showing the configuration of a clamping plate provided as part of the battery manufacturing apparatus. FIG. 10 is a cross-sectional view taken along the arrow A-A in FIG. 5. FIG. 11 is a front view showing the configuration of a plunger provided in the clamping plate. FIG. 12 is a longitudinal cross-sectional view showing the configuration of a plunger provided in the clamping plate. FIG. 13 is another longitudinal cross-sectional view showing the configuration of a plunger provided in the clamping plate. FIG. 14 is a view showing a stacking step of a laminate by the battery manufacturing apparatus in the manufacture of the all-solid-state battery. FIG. 15 is a view showing a pressurizing step of a laminate by the battery manufacturing apparatus in the manufacture of the all-solid-state battery. FIG. 16 is a plan view showing the configuration of a clamping plate according to a modified embodiment. FIG. 17 is a plan view showing the configuration of a clamping plate according to another modified embodiment.

[0011] [Embodiment] Hereinafter, one embodiment of the present invention will be described in detail.

[0012] <Configuration of All-Solid-State Battery> In this embodiment, as an example of an all-solid-state battery, an all-solid-state secondary battery using a lithium ion conductive solid electrolyte, i.e., an all-solid-state lithium ion secondary battery, will be described. However, it goes without saying that the all-solid-state battery according to the present invention is not limited to an all-solid-state lithium ion secondary battery.

[0013] FIG. 1 is a side view showing the configuration of a laminate 10 that constitutes an all-solid-state battery manufactured by a battery manufacturing apparatus described below.

[0014] As shown in FIG. 1 , the laminate 10 includes a positive electrode layer 11 (first electrode layer), a negative electrode layer 12 (second electrode layer), and a solid electrolyte layer 13. The positive electrode layer 11 is an electrode layer having a positive polarity. The negative electrode layer 12 is an electrode layer having a polarity opposite to that of the positive electrode layer 11, i.e., a negative polarity. In this manner, the positive electrode layer 11 and the negative electrode layer 12 have opposite polarities. The solid electrolyte layer 13 is a layer formed of a solid electrolyte and is interposed between the positive electrode layer 11 and the negative electrode layer 12. The planar shape of the laminate 10 is rectangular (e.g., square). However, the planar shape of the laminate 10 is not limited to a rectangular shape and may be, for example, circular.

[0015] The positive electrode layer 11 is formed of a composite (mixture) of a positive electrode active material and a solid electrolyte, or of only the positive electrode active material. The positive electrode active material may be a material commonly used as a positive electrode active material in the field of all-solid-state batteries. Examples of the positive electrode active material include lithium-containing oxides (e.g., lithium cobalt oxide (LiCoO), lithium nickel oxide (LiNiO), and lithium manganese oxide (LiMnO)).

[0016] The negative electrode layer 12 is formed of a composite (mixture) of a negative electrode active material and a solid electrolyte, or of only the negative electrode active material. The negative electrode active material may be any material commonly used in the field of all-solid-state batteries. Examples of the negative electrode active material include graphite (natural graphite, artificial graphite, etc.), carbon materials (graphite carbon fiber, resin-baked carbon, etc.), tin, lithium, oxides, sulfides, nitrides, alloys, etc., regardless of the form of powder, foil, etc.

[0017] The solid electrolytes used in the positive electrode layer 11, the negative electrode layer 12, and the solid electrolyte layer 13 are materials that are commonly used in the field of lithium ion batteries. Examples of such solid electrolytes include organic compounds, inorganic compounds, and materials made of both organic and inorganic compounds. Among inorganic compounds, Li ２ S-P ２ S ５ Sulfides such as these have superior ionic conductivity compared to other inorganic compounds.

[0018] The all-solid-state battery is constructed by enclosing a battery unit including at least one laminate 10, a positive electrode current collector, and a negative electrode current collector (not shown) in an exterior body (not shown). The positive electrode current collector is a conductive member that contacts the positive electrode layer 11 of the laminate 10. The negative electrode current collector is a conductive member that contacts the negative electrode layer 12 of the laminate 10. The positive electrode current collector and the negative electrode current collector have tabs that are drawn out to the outside of the exterior body, and are electrically connected to the outside by the tabs.

[0019] <General Configuration of Battery Manufacturing Apparatus> FIG. 2 is a front view showing the configuration of the battery manufacturing apparatus 1. As shown in FIG.

[0020] The battery manufacturing apparatus 1 shown in Fig. 2 is an apparatus for pressure-molding a laminate 10. The battery manufacturing apparatus 1 includes a base 2, a press 3, a handling robot 4, a feeder 5, and a clamping plate 6. The base 2 is a platform that supports the press 3, the handling robot 4, and the feeder 5.

[0021] The battery manufacturing apparatus 1 alternately places the laminate 10 on the press 3 using the handling robot 4 and places the clamping plates 6 on the press 3 using the feeder 5, thereby stacking the laminate 10 and the clamping plates 6 alternately in the thickness direction of the laminate 10. The battery manufacturing apparatus 1 pressurizes the stacked laminate 10 and the clamping plates 6 using the press 3. The battery manufacturing apparatus 1 retrieves the laminate 10 after pressure molding from the press 3 using the handling robot 4, and retrieves the clamping plates 6 from the press 3 after pressure molding using the feeder 5.

[0022] <Configuration of Press Machine> The press machine 3 has press pins 31 and 32 (pressure units), a drive shaft 33, a drive unit 34, and a support unit 35. The press machine 3 is, for example, a uniaxial press machine.

[0023] The press pin 31 is disposed on the base 2, and the laminate 10 and the clamping plates 6 are stacked on the upper surface. The press pin 32 is provided so as to be movable up and down, and by descending, applies pressure to the laminate 10 and the clamping plates 6 stacked on the press pin 31. The drive shaft 33 is a shaft that drives the press pin 32 to move up and down, and its lower end is connected to the upper end surface of the press pin 32. The drive unit 34 has a drive mechanism, such as a mechanical or hydraulic type, to drive the drive shaft 33 to move up and down. The support unit 35 supports the drive unit 34 on the base 2.

[0024] The above-described configuration of the press machine 3 is one example, and other configurations may be used as long as they can apply pressure from above to the stacked laminate 10 and the clamping plates 6. For example, the press machine 3 may be configured to raise press pins 31 on which the stacked laminate 10 and the clamping plates 6 are placed, thereby pressing the stacked laminate 10 and the clamping plates 6 against press pins 32 fixed at predetermined positions above, thereby applying pressure.

[0025] <Configuration of Handling Robot> FIG. 3 is a plan view showing the configuration of the handling robot 4. As shown in FIG.

[0026] The handling robot 4 is a robot that transfers the laminate 10. Specifically, the handling robot 4 is a robot that picks up the laminate 10 from a predetermined transfer position, transfers it to above the press pins 31, places it on the press pins 31, and returns the pressure-molded laminate 10 on the press pins 31 to the transfer position. As also shown in Fig. 3 , the handling robot 4 has a main body 41, a pair of arms 42, and a tray 43.

[0027] The main body 41 is provided on the base 2 and houses a drive mechanism that drives the arms 42. The arms 42 are arranged in parallel with a gap between them. By narrowing the gap between them, the arms 42 clamp the stack 10 on both sides, and by widening the gap between them, the arms 42 are released from clamping of the stack 10 and are in a standby state. The arms 42 transport the stack 10 horizontally between a position above a transfer position in the front of the battery manufacturing apparatus 1 (the position indicated by the two-dot chain line in FIG. 3 ) and a specified position above the press pins 31 of the press machine 3. The arms 42 also transport the stack 10 vertically between the position above the transfer position and the transfer position, and between the position above the press pins 31 and the position where the stack 10 is placed.

[0028] At the transfer position, the arm 42 transfers the laminate 10 to a conveyor (not shown). The conveyor transports the laminate 10 between the transfer position and a storage location where the laminate 10 is stored before and after pressure molding.

[0029] The tray 43 is a plate-like member disposed on the lower end side of the arms 42. The tray 43 supports the laminate 10, which is sandwiched between the arms 42, on the lower side of the arms 42. The positive electrode layer 11, the negative electrode layer 12, and the solid electrolyte layer 13 that constitute the laminate 10 are each formed from a powder material and are therefore fragile before pressure molding. For this reason, the laminate 10 will crumble if it is sandwiched between the arms 42 with a strong force. Therefore, by supporting the laminate 10 with the tray 43, the arms 42 can sandwich the laminate 10 with a relatively weak force.

[0030] The above-described configuration of the handling robot 4 is merely an example, and it goes without saying that the handling robot 4 is not limited to this configuration. For example, the handling robot 4 may be an articulated robot.

[0031] <Configuration of Feeder> FIG. 4 is a plan view showing the configuration of the feeder 5. As shown in FIG.

[0032] The supply machine 5 is a robot that supplies the clamping plates 6 to the press machine 3 and retrieves the clamping plates 6 from the press machine 3. As also shown in FIG. 4 , the supply machine 5 has a main body 51 and a pair of arms 52.

[0033] The main body 51 is provided on the base 2 and houses a drive mechanism that drives the arm 52 in the vertical direction, and a plurality of clamping plates 6. The plurality of clamping plates 6 are stored in a vertically stacked manner at the bottom of the main body 51. Also, although not shown, the main body 51 is provided with an elevating mechanism that moves the clamping plates 6 up and down between a storage position and the lower limit position of the arm 52.

[0034] The arms 52 are arranged parallel to each other at a distance from each other, and by narrowing the gap between them, they clamp the clamping plates 6 on both sides, while by widening the gap between them, they are placed in a state where they release the clamping of the clamping plates 6 and in a standby state. The arms 52 are belt conveyors having a width greater than the thickness of the clamping plates 6. The belt conveyors are arranged so that the belt surfaces face each other between the arms 52. The arms 52 use the belt conveyor to transport the clamped clamping plates 6 horizontally between a position above the press pins 31 and the interior of the main body 51. During stacking, the arms 52 lower the clamping plates 6 from a position above the press pins 31 to a position where the clamping plates 6 are placed above the press pins 31, and after stacking, they raise the clamping plates 6 from the position where they are placed to an upper position.

[0035] <Configuration of clamping plate> Fig. 5 is a plan view showing a clamping plate 6 provided as part of the battery manufacturing apparatus. Fig. 6 is a cross-sectional view taken along line A-A in Fig. 5. Fig. 7 is a front view showing the configuration of a plunger 63 provided on the clamping plate 6. Fig. 8 is a vertical cross-sectional view showing the configuration of the plunger 63. Fig. 9 is another vertical cross-sectional view showing the configuration of the plunger 63.

[0036] As shown in FIGS. 5 and 6, the clamping plate 6 has a clamping portion 61, a peripheral portion 62, and a plunger 63 (middle portion).

[0037] The clamping portion 61 is a plate-shaped member at least a portion of which is clamped between the two laminates 10. The planar shape of the clamping portion 61 is the same as the planar shape of the laminate 10, and the area of ​​the planar portion is larger than the area of ​​the planar portion of the laminate 10. The clamping portion 61 is formed of a high-strength material because a high pressure is applied to it by the press 3. Examples of high-strength materials include tool steel and die steel.

[0038] The peripheral portion 62 is a plate-like member provided around the clamping portion 61 at a distance from the clamping portion 61. The peripheral portion 62 is formed in a frame shape so as to surround the clamping portion 61. The peripheral portion 62 is formed in a shape corresponding to the planar shape of the clamping portion 61. The peripheral portion 62 is not sandwiched between the two laminates 10, and is therefore not pressed by the press 3. Therefore, the peripheral portion 62 is not required to have a higher strength than the clamping portion 61. However, from the viewpoint of standardizing the material, the peripheral portion 62 may be formed from the same material as the clamping portion 61.

[0039] Holes 62a are provided at intervals in the peripheral portion 62. The holes 62a are formed to penetrate the peripheral portion 62 in a direction perpendicular to the outer peripheral surface and the inner peripheral surface. A plunger 63 is fitted into the holes 62a.

[0040] The plunger 63 is connected to the clamping portion 61 and the surrounding portion 62, and has lower rigidity than the clamping portion 61. Because the plunger 63 has lower rigidity than the clamping portion 61, it has elasticity. As shown in FIGS. 7 and 8, the plunger 63 has a housing 631, a ball 632, and a spring 633. The housing 631 is cylindrical with a bottom, and has a recess 631a formed inside. The spring 633 is fitted into and fixed in the recess 631a.

[0041] When plunger 63 receives an external force applied to ball 632, spring 633 is compressed, and ball 632 is pushed into recess 631a as shown in Fig. 9. When the external force applied to ball 632 is removed, the restoring force of spring 633 pushes ball 632 out of recess 631a as shown in Fig. 8. Due to this structure, plunger 63 has elasticity.

[0042] The plunger 63 is disposed in the hole 62a so that the ball 632 faces the side surface of the clamping portion 61. A groove 61a having a V-shaped cross section is formed around the entire periphery on the side surface of the clamping portion 61. The ball 632 of the plunger 63 is pressed toward the side surface of the clamping portion 61 by the elastic force of the spring 633 and fits into the groove 61a.

[0043] In this way, the plunger 63 is connected to the peripheral portion 62 by being fixed to the peripheral portion 62. The plunger 63 is also connected to the clamping portion 61 by fitting the ball 632 into the groove 61a.

[0044] <Pressure Molding of Laminate> The pressure molding of the laminate 10 in the production of an all-solid-state battery will be described.

[0045] Fig. 10 is a diagram showing a step of stacking the laminate 10 by the battery manufacturing apparatus 1 in the production of an all-solid-state battery. Fig. 11 is a diagram showing a step of pressurizing the laminate 10 by the battery manufacturing apparatus 1 in the production of an all-solid-state battery.

[0046] As shown in FIG. 10, first, in the press machine 3, with the press pins 32 in the standby position, the feeder 5 places the clamping plate 6 on the press pins 31, and the handling robot 4 places the laminate 10 on top of it (step S1).

[0047] In step S1, the supply machine 5 takes out the clamping plate 6 stored in the main body 51, and transfers the clamping plate 6 to above the press pins 31 by the arms 52 and lowers it onto the press pins 31. Thereafter, the supply machine 5 waits with the gap between the arms 52 widened to outside the range where the press pins 32 are lowered.

[0048] In step S1, the handling robot 4 receives the laminate 10 from the conveyor at the delivery position using the arm 42, transports the laminate 10 to above the press pins 31, and lowers it onto the clamping plates 6. The handling robot 4 positions the laminate 10 so that it rests on the clamping portions 61 of the clamping plates 6 without extending beyond the peripheral portions 62. The handling robot 4 then moves to a position outside the range where the press pins 32 are lowered and waits.

[0049] Next, the feeder 5 places the clamping plate 6 on the stack 10 placed in step S1 (step S2). In step S2, the feeder 5 removes the clamping plate 6 from the main body 51, lowers the clamping plate 6 onto the stack 10 by the arm 52, and transitions to a standby state, as in step S1. The feeder 5 places the clamping plate 6 so that the clamping portion 61 rests on the stack 10.

[0050] Next, the handling robot 4 places the stack 10 on the clamping plate 6 placed in step S2 (step S3). In step S3, the feeder 5 removes the clamping plate 6 from the main body 51, and lowers the clamping plate 6 onto the stack 10 by the arm 52, as in step S1, and transitions to a standby state.

[0051] Then, the supplying machine 5 places the clamping plate 6 on the stack 10 placed in step S3, similar to step S2 (step S4). Furthermore, the handling robot 4 places the stack 10 on the clamping plate 6 placed in step S4, similar to step S3 (step S5). Finally, the supplying machine 5 places the clamping plate 6 on the stack 10 placed in step S5, similar to step S2 (step S6).

[0052] In this way, the clamping plates 6 and the laminates 10 are alternately stacked in the thickness direction of the laminates 10 (stacking process). Here, the process of placing three laminates 10 on the press pins 31 has been described, but the number of laminates 10 placed on the press pins 31 is not limited to this.

[0053] In the battery manufacturing apparatus 1, the clamping plates 6 stored in the main body 51 of the supply machine 5 are transported between the main body 51 and the press machine 3 by the arm 52. Alternatively, the clamping plates 6 may be placed on the press pins 31 and retrieved manually. Specifically, the worker retrieves the clamping plates 6 from a clamping plate 6 storage provided in the battery manufacturing apparatus 1, first places the clamping plates 6 on the press pins 31, and then places the clamping plates 6 on the stacks 10. When placing the clamping plates 6 on the stacks 10, the worker places the clamping plates 6 so that the clamping portions 61 are on the stacks 10, similar to step S2 described above.

[0054] When the worker places the clamping plates 6, the worker may operate the handling robot 4 and place the clamping plates 6 after the stack 10 has been placed by the handling robot 4. Alternatively, the handling robot 4 may have a sensor that detects the clamping plates 6, and when the sensor detects the clamping plates 6 placed by the worker, the worker may place the stack 10 on the clamping plates 6.

[0055] In retrieving the clamping plates 6 after pressurizing and forming the laminate 10, similar to the above-described placement of the clamping plates 6, the worker may operate the handling robot 4 and retrieve the clamping plates 6 after the laminate 10 has been retrieved by the handling robot 4. Alternatively, the handling robot 4 may have a sensor that detects the laminate 10, and retrieve the laminate 10 when the worker detects the laminate 10 by removing the clamping plates 6 from above the laminate 10.

[0056] After step S6, as shown in Fig. 11, the press pins 32 are lowered so as to abut against the uppermost clamping plate 6, and the clamping plates 6 and the laminate 10 stacked on the press pins 31 are pressed in the thickness direction of the laminate 10 (pressing step). In the pressing step, pressing is performed at a predetermined pressure and a predetermined temperature for a specified time.

[0057] When the pressurization process is completed, the press pins 32 rise and return to their standby positions, the feeder 5 retrieves the clamping plates 6, and the handling robot 4 retrieves the pressure-molded laminate 10. The feeder 5 transports the laminate 10, with the clamping plates 6 held by the arms 52, into the main body 51 and hands it over to the lifting mechanism. The lifting mechanism lowers the clamping plates 6 and returns it to the storage position. The handling robot 4 transports the laminate 10, supported by the arms 42 and tray 43, from on the press pins 31 to the delivery position and hands it over to the conveyor. The conveyor transports the laminate 10 received from the handling robot 4 to a storage location.

[0058] As described above, the battery manufacturing apparatus 1 stacks the clamping plates 6 and the stack 10 in the press 3 and then applies pressure. However, the battery manufacturing apparatus 1 is not limited to this configuration, and the clamping plates 6 and the stack 10 may be stacked outside the press 3, and the stacked clamping plates 6 and stack 10 may be transported to the press 3 and then applied pressure.

[0059] Effects of the Embodiment As described above, the battery manufacturing apparatus 1 according to the present embodiment includes the press 3 having the press pins 31, 32, and the clamping plate 6 stored in the press 3. The battery manufacturing method using the battery manufacturing apparatus 1 also includes the stacking step and the pressurizing step described above.

[0060] In the pressurizing step, a large pressure is applied to the clamping portion 61 of the clamping plate 6 in the thickness direction of the clamping portion 61. As a result, the clamping portion 61 is deformed in the planar direction due to stress concentrated at the outer circumferential edge. Because the plunger 63 of the clamping plate 6 is elastic, the ball 632 of the plunger 63 is pushed into the recess 631a and elastically deforms as the clamping portion 61 deforms, thereby easing the stress concentration at the outer circumferential edge of the clamping portion 61. This reduces damage to the clamping plate 6.

[0061] Furthermore, the reduction in stress concentration as described above allows the thickness of the clamping portion 61 to be reduced, and therefore the entire clamping plate 6 can be formed thin.

[0062] It is preferable that the area of ​​the side of the clamping portion 61 that contacts the laminate 10 (the area of ​​the first surface) is equal to or greater than the area of ​​the surface along the laminate surface where the positive electrode layer 11 and the negative electrode layer 12 in the laminate 10 contact the solid electrolyte layer 13 (the area of ​​the second surface).

[0063] If the area of ​​the first surface is smaller than the area of ​​the second surface, the end of the laminate 10 reaches the peripheral portion 62. This causes a difference in the stress generated in the laminate 10 between the clamping portion 61 side and the peripheral portion 62 side. The laminate 10 will be damaged if a shear force generated by this difference acts on it.

[0064] In contrast, by making the area of ​​the first surface equal to or greater than the area of ​​the second surface, the laminate 10 can be positioned so that the second surface is contained within the range of the first surface. This prevents the laminate 10 from reaching the peripheral portion 62. Therefore, the above-described shear force is not applied to the laminate 10. This prevents damage to the laminate 10.

[0065] <Modification> FIG. 12 is a plan view showing the configuration of a clamping plate 6A according to a modification of this embodiment.

[0066] The battery manufacturing apparatus 1 described above includes a clamping plate 6A shown in Fig. 12 instead of the clamping plate 6. Like the clamping plate 6, the clamping plate 6A includes a clamping portion 61, a peripheral portion 62, and a plunger 63, but differs from the clamping portion 61 in that it further includes a pin 7 and the peripheral portion 62 includes a fitting hole 62b. The pin 7 and the fitting hole 62b form a positioning structure for the clamping plate 6A.

[0067] The pins 7 and the fitting holes 62b are provided at the four corners of the peripheral portion 62. Fig. 12 shows a longitudinal cross section of one side of the peripheral portion 62 in the longitudinal direction, including two adjacent corners of the four corners of the peripheral portion 62. Note that the pins 7 and the fitting holes 62b may be provided at positions other than the four corners of the peripheral portion 62.

[0068] The positioning structure is provided to determine the position of the clamping plate 6A, which faces the clamping plate 6A with the laminate 10 between them, when the clamping plate 6A and the laminate 10 are stacked on the press pins 31. The pins 7 are fixed to the peripheral portion 62 by having the ends opposite their heads held in retaining holes 62c provided in the peripheral portion 62. The retaining holes 62c are formed to a predetermined depth in the thickness direction from the upper surface side of the peripheral portion 62. The fitting holes 62b have a size and shape to fit the heads of the pins 7 and are formed to a predetermined depth in the thickness direction of the peripheral portion 62 from the lower surface side of the peripheral portion 62 so as to connect to the retaining holes 62c. The reason for connecting the fitting holes 62b and the retaining holes 62c in this manner is to form the clamping plate 6A thin and thereby reduce its weight. However, if the clamping plate 6A is made thicker, the fitting holes 62b and the retaining holes 62c do not need to be connected.

[0069] The above-described positioning structure standardizes the structure of the clamping plate 6A by aligning the positions of the fitting holes 62b and the retaining holes 62c in the peripheral portion 62. In order to ensure the required depths of the fitting holes 62b and the retaining holes 62c at the same positions, such clamping plates 6A cannot be made thinner than the combined depth of the fitting holes 62b and the retaining holes 62c. In contrast, although not shown, it is possible to reduce the thickness of the clamping plates 6A by providing two different types of clamping plates 6A as follows.

[0070] One type of clamping plate 6A (referred to as the first clamping plate) has fitting holes 62b and retaining holes 62c formed at different positions in the peripheral portion 62. The other type of clamping plate 6A (referred to as the second clamping plate) is placed on top of the first clamping plate, and has fitting holes 62b formed at positions that coincide with the retaining holes 62c of the first clamping plate, and retaining holes 62c formed at positions that coincide with the fitting holes 62b of the first clamping plate, respectively. The first clamping plate and the second clamping plate are placed alternately.

[0071] As a result, the pins 7 held in the retaining holes 62c of the first clamping plate fit into the fitting holes 62b of the second clamping plate placed on top of the first clamping plate, and the pins 7 held in the retaining holes 62c of the second clamping plate fit into the fitting holes 62b of the first clamping plate placed on top of the second clamping plate. With this positioning structure, the fitting holes 62b and the retaining holes 62c are provided in different positions, so that the clamping plate 6A can be made thin to the depths required for the fitting holes 62b and the retaining holes 62c.

[0072] With this positioning structure, when the clamping plates 6A and the laminate 10 are alternately stacked on the press pins 31, the heads of the pins 7 held by the lower clamping plate 6A are fitted into the fitting holes 62b of the upper clamping plate 6A. This allows accurate and easy positioning of the opposing clamping plates 6 with the laminate 10 between them. This allows efficient pressure molding of the laminate 10.

[0073] FIG. 13 is a plan view showing the configuration of a clamping plate 6B according to another modified example of this embodiment.

[0074] The above-described battery manufacturing apparatus 1 includes a clamping plate 6B shown in Fig. 13 instead of the clamping plate 6. Like the clamping plate 6, the clamping plate 6B has a clamping portion 61 and a peripheral portion 62, but differs from the clamping plate 6 in that it has a connecting portion 64 (middle portion) instead of the plunger 63. The connecting portion 64 is made of an elastic material such as rubber.

[0075] As a result, similar to the plunger 63, the connecting portion 64 is elastically deformed, thereby alleviating stress concentration at the outer peripheral end of the clamping portion 61. This makes it possible to reduce damage to the clamping plate 6.

[0076] [Summary] As described above, the battery manufacturing apparatus according to aspect 1 of the present invention is a battery manufacturing apparatus that pressure-forms a laminate that includes a first electrode layer, a second electrode layer having a polarity opposite to that of the first electrode layer, and a solid electrolyte layer interposed between the first electrode layer and the second electrode layer, and includes a pressure unit that presses a plurality of the laminates that are stacked in the thickness direction of the laminates, a clamping unit at least a portion of which is sandwiched between two of the laminates, a peripheral unit that is provided around the clamping unit and spaced apart from the clamping unit, and a clamping plate that is connected to the clamping unit and the peripheral unit and has an intermediate unit with lower rigidity than the clamping unit.

[0077] In the above configuration, when the clamping portion is pressed in its thickness direction as a result of the pressure applied to the laminate by the pressure applying portion, the middle portion is deformed by the stress concentrated at the outer peripheral edge of the clamping portion, thereby alleviating the stress concentration at the outer peripheral edge of the clamping portion, thereby reducing damage to the clamping plates.

[0078] A battery manufacturing apparatus according to a second aspect of the present invention is the battery manufacturing apparatus according to the first aspect, wherein the intermediate portion has elasticity.

[0079] In the above configuration, the intermediate portion is elastically deformed by the stress concentrated on the outer peripheral end of the clamping portion, thereby efficiently alleviating the stress concentrated on the outer peripheral end of the clamping portion.

[0080] A battery manufacturing apparatus according to a third aspect of the present invention may be configured such that, in the first or second aspect described above, the area of ​​a first surface of the clamping portion that contacts the stack is equal to or greater than the area of ​​a second surface that is a surface along the stacking surface where the first electrode layer and the second electrode layer of the stack contact the solid electrolyte layer.

[0081] If the area of ​​the first surface is smaller than the area of ​​the second surface, the edge of the laminate reaches the peripheral portion, which causes a difference in stress between the sandwiched portion side and the peripheral portion side of the laminate, resulting in shear force that damages the laminate.

[0082] In contrast, in the above configuration, the area of ​​the first surface is equal to or greater than the area of ​​the second surface, so the laminate can be positioned so that the second surface is contained within the range of the first surface. This prevents the laminate from reaching the peripheral portion, so no shear force acts on the laminate. Therefore, it is possible to prevent the laminate from shearing.

[0083] A battery manufacturing apparatus according to a fourth aspect of the present invention is the battery manufacturing apparatus according to the first or second aspect, wherein the clamping plate may have a positioning structure for determining the position of the clamping plate facing the clamping plate with the stack therebetween.

[0084] In the above-described configuration, the clamping plates can be positioned accurately and easily, thereby enabling the laminate 10 to be efficiently pressure-molded.

[0085] A battery manufacturing method according to a fifth aspect of the present invention is a battery manufacturing method for pressure-molding a laminate including a first electrode layer, a second electrode layer having a polarity opposite to that of the first electrode layer, and a solid electrolyte layer interposed between the first electrode layer and the second electrode layer, the method including a stacking step of alternately stacking the laminate, a clamping portion at least a portion of which is sandwiched between the two laminates, a peripheral portion provided around the clamping portion at a distance from the clamping portion, and a clamping plate connected to the clamping portion and the peripheral portion and having an intermediate portion having a lower rigidity than the clamping portion, in a thickness direction of the laminate, and a pressurizing step of pressurizing the stacked laminate and the clamping plate in the thickness direction.

[0086] According to the above method, as in the battery manufacturing apparatus, the stress concentrated on the outer peripheral edge of the clamping plate due to the pressure applied to the stack by the pressure unit is alleviated by the middle part, thereby reducing damage to the clamping plates.

[0087] [Notes] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Furthermore, the technical scope of the present invention also includes configurations obtained by appropriately combining the technical means disclosed in the respective embodiments.

[0088] REFERENCE SIGNS LIST 1 Battery manufacturing device 6, 6A, 6B Clamping plate 7 Pin (positioning structure) 11 Positive electrode layer (first electrode layer) 12 Negative electrode layer (second electrode layer) 13 Solid electrolyte layer 31, 32 Press pin (pressure portion) 61 Clamping portion 62 Surrounding portion 62b Fitting hole (positioning structure) 63 Plunger (middle portion) 64 Connection portion (middle portion)

Claims

1. A battery manufacturing device that pressure-forms a laminated body that includes a first electrode layer, a second electrode layer having a polarity opposite to that of the first electrode layer, and a solid electrolyte layer interposed between the first electrode layer and the second electrode layer, the battery manufacturing device comprising: a pressurizing unit that presses a plurality of the laminated bodies that are stacked in the thickness direction of the laminated bodies; a clamping unit that clamps at least a portion of the laminated bodies between two of the laminated bodies, a peripheral unit that is provided around the clamping unit and spaced apart from the clamping unit, and a clamping plate that is connected to the clamping unit and the peripheral unit and has an intermediate unit with lower rigidity than the clamping unit.

2. The battery manufacturing apparatus according to claim 1, wherein the intermediate portion has elasticity.

3. A battery manufacturing apparatus as described in claim 1 or 2, wherein the area of ​​the first surface of the clamping portion that contacts the stack is equal to or greater than the area of ​​the second surface, which is the surface along the stacking surface where the first electrode layer and the second electrode layer of the stack contact the solid electrolyte layer.

4. The battery manufacturing apparatus according to claim 1 or 2, wherein the sandwiching plate has a positioning structure for determining the position of the sandwiching plate facing the stack between them.

5. A battery manufacturing method for pressure-molding a laminate comprising a first electrode layer, a second electrode layer having a polarity opposite to that of the first electrode layer, and a solid electrolyte layer interposed between the first electrode layer and the second electrode layer, the battery manufacturing method comprising: a lamination step of alternately stacking the laminate, a clamping portion at least a portion of which is sandwiched between two of the laminates, a peripheral portion provided around the clamping portion with a gap between the clamping portion, and a clamping plate connected to the clamping portion and the peripheral portion and having an intermediate portion with lower rigidity than the clamping portion, in the thickness direction of the laminate; and a pressurization step of pressurizing the stacked laminate and the clamping plate in the thickness direction.

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