Battery cell manufacturing equipment

Abstract

Ensure proper resin welding during the manufacturing of battery cells. [Solution] The battery cell manufacturing apparatus 9 includes a first heating plate 91 that seals the openings 12 and 13 of the container 10 by applying pressure and heating the outer material 11 and resin 5 that form the container 10 of the battery cell 1 in the stacking direction, and a second heating plate 92 that seals the edges of the container by applying pressure and heating the edges of the outer materials that overlap in the stacking direction, at least in the stacking direction.

Description

Technical Field

[0001] The technology disclosed herein relates to a manufacturing apparatus for battery cells.

Background Art

[0002] Patent Document 1 describes a conventional laminated battery. A laminated battery is a battery in which an electrode body is housed in an exterior member. The laminated battery includes a plurality of current collector terminals drawn out from the electrode body to the outside of the exterior member. The plurality of current collector terminals overlap with a thermoplastic resin interposed therebetween. At the peripheral edge of the exterior member, the resins are welded to each other and welded to the exterior member, whereby the peripheral edge of the exterior member from which the current collector terminals are drawn out is closed. In the laminated battery, each of the plurality of current collector terminals is drawn out to the outside of the exterior member. The plurality of current collector terminals are not connected to each other inside the exterior member. In the laminated battery, the space inside the exterior member can be used for the expansion of the electrode body. The structure of the laminated battery is advantageous for improving the energy density of the battery.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The above-mentioned laminated battery is manufactured by a heat-sealing process. In the heat-sealing process, the resins overlapping at the peripheral edge of the exterior member are welded to each other by pressing the hot plate, which is an energy supply source, against the overlapping direction. Also, the exterior members overlapping at the peripheral edge of the exterior member, which are on the side of the resin, are joined by a heat-sealing process using a hot plate.

[0005] As the number of electrodes stacked within the battery cell increases, the number of current collectors drawn out of the outer casing increases, which in turn increases the amount of resin welded during the heat sealing process. Figure 7 illustrates a battery cell manufacturing apparatus 90 when the number of resins 5 to be welded is large. Figure 7 shows a cross-section corresponding to the opening 19 of the container 10. The container 10 is formed by stacking sheet-like outer casing materials 11 and welding the edges of the outer casing materials 11 together in the stacking direction (i.e., the vertical direction of the paper in Figure 7). The container 10 houses the power generation element inside. Reference numeral 30 denotes the current collector 30 of the power generation element that protrudes out of the container 10 through the opening 19. Note that the opening 19 of the container 10 here means the opening from which the current collector 30 is drawn out. The area where the edges of the outer casing materials 11 are welded together is not included in the opening 19.

[0006] Because there are many resins 5 to be welded, the thickness T of the opening 19 is significantly thicker than the thickness of the welded joints between the edges of the exterior material 11. Here, thickness T is the distance from the top of the opening 19 to the edge of the exterior material 11. A corner portion 18 is formed between the side of the opening 19 and the welded joints between the edges of the exterior material 11 adjacent to that side.

[0007] By performing the welding of the resin 5 and the welding of the edges of the exterior material 11 simultaneously, the manufacturing time for the battery cell can be reduced. The hot plate 99 used for welding the resin 5 can be shaped to match the shape of the battery cell, and may have a recessed portion 98. The depth D of the recessed portion 98 is set in advance to correspond to the thickness T of the opening 19, and the width W of the recessed portion 98 is set in advance to correspond to the width of the opening 19.

[0008] However, the pressure and temperature required for the heating plate 99 at the point where the numerous laminated resins 5 are welded together are different from the pressure and temperature required at the point where the edges of the exterior material 11 are welded together. It is difficult for the heating plate 99 to properly weld both the numerous laminated resins 5 and the edges of the exterior material 11 together.

[0009] Furthermore, since numerous resins 5 are laminated, it is conceivable to set the depth D and width W of the recessed portion 98 to be larger in advance to account for variations in the shape of the resins 5. However, if the size of the recessed portion is made larger, a gap may be created between the resin 5 and the exterior material 11 during hot plate welding, which may prevent the opening 19 from being stably sealed.

[0010] Furthermore, a heat plate 99 with a fixed size of recessed portion 98 can only be used to manufacture battery cells of the same shape. For example, if the number of electrode layers in a battery cell differs, the thickness T of the opening 19 changes. A heat plate 99 having a recessed portion 98 of depth D cannot be used to manufacture battery cells with different opening thicknesses T. A heat plate 99 having a recessed portion 98 has low versatility.

[0011] The technology disclosed herein enables proper welding of resin during the manufacturing of battery cells. [Means for solving the problem]

[0012] The technology disclosed herein relates to a battery cell manufacturing apparatus.

[0013] The battery cell comprises a container housing a power generation element in which a plurality of electrodes are stacked in the stacking direction, a plurality of current collectors connected to the electrodes within the container, which are stacked in the stacking direction and protrude out of the container through the opening of the container, and a resin that seals the opening of the container by being welded to the current collectors between the stacked current collectors. The container having the opening is formed by welding together the edges of the outer materials that are stacked in the stacking direction.

[0014] The battery cell manufacturing apparatus is, A first heating plate seals the opening at the position of the opening of the container by applying pressure and heating the outer material and the resin in the lamination direction, A second heating plate is provided on the side of the resin at the opening of the container, which pressurizes and heats the edges of the exterior materials that overlap in the stacking direction, at least in the stacking direction, to weld the edges of the exterior materials together. It is equipped with.

[0015] In a battery cell, each of the stacked current collectors protrudes out of the container through an opening. The multiple current collectors are connected, for example, to electrodes with the same polarity. The multiple current collectors are not connected to each other inside the container. The connection space between current collectors inside the container can be eliminated. The electrodes of the battery cell can be enlarged using the space inside the container. Battery cells with this structure can have a high energy density.

[0016] The opening of the container is sealed with resin. The resin is, for example, a thermoplastic resin. A container with an opening is formed by welding the edges of the outer materials that overlap in the stacking direction together. Note that the opening of the container referred to here is the part from which the current collector protrudes and which is sealed with resin. The part where the edges of the outer materials are welded together is not included in the opening of the container.

[0017] The battery cell manufacturing equipment performs welding of the outer casing material and resin, as well as welding of the edges of the outer casing material.

[0018] The first heating plate pressurizes and heats the outer material and resin in the stacking direction at the opening of the container. In order to weld together the multiple layers of resin, the first heating plate requires relatively high pressure and relatively high temperature.

[0019] The second heating plate applies pressure and heat to the edges of the outer packaging material in the lamination direction, on the side of the resin at the opening of the container. Since the edges of the outer packaging material are sealed by welding them together, the second heating plate requires a relatively low pressure and a relatively low temperature.

[0020] The manufacturing apparatus described above welds different parts of a battery cell using a first hot plate and a second hot plate. The pressing force and temperature of the first hot plate can be optimized, and the pressing force and temperature of the second hot plate can be optimized. The manufacturing apparatus described above can appropriately perform welding during the manufacture of the battery cell. Further, since different parts of the battery cell can be welded simultaneously using the first hot plate and the second hot plate, the manufacturing apparatus described above enables reduction of the manufacturing man-hours.

[0021] A corner portion is formed between a side portion of the opening and an edge portion of the container. The first hot plate presses the exterior material and the resin in the stacking direction by moving in the stacking direction. The second hot plate may have a first surface that contacts a side portion of the opening and a second surface that contacts an edge portion of the container, and presses the exterior material in a direction orthogonal to the stacking direction and in the stacking direction by moving in a diagonal direction approaching the opening with respect to the stacking direction.

[0022] In a laminate in which a plurality of resins are stacked, there is a risk that dimensional variations will increase. If the dimensional variations are large, there is a risk that a gap will occur between the resin and the exterior material in a direction orthogonal to the stacking direction or in the stacking direction at the opening of the container.

[0023] On the other hand, in the manufacturing apparatus described above, the first hot plate moves in the stacking direction. The first hot plate can appropriately weld a plurality of resins and an exterior material stacked at the opening by pressing the exterior material and the resin in the stacking direction.

[0024] The second hot plate moves in a diagonal direction approaching the opening with respect to the stacking direction. The first surface of the second hot plate contacts the side portion of the opening and presses the exterior material in a direction orthogonal to the stacking direction. The exterior material is welded to the side portion of the resin stacked at the opening without a gap. Generation of a gap between the resin and the exterior material in a direction orthogonal to the stacking direction is suppressed. The second surface of the second hot plate contacts the edge portion of the container and presses the exterior material in the stacking direction. The edges of the exterior material are appropriately welded together.

[0025] The second hot plate that can move in a direction different from the first hot plate can, together with the first hot plate, suppress the occurrence of a gap at the opening of the container and stably seal the opening.

[0026] The relative movement amount of the first hot plate in the stacking direction with respect to the second hot plate may be variable.

[0027] If the relative movement amount of the first hot plate is variable, the manufacturing apparatus for the battery cell can optimize the position of the first hot plate according to the shape of the battery cell. The manufacturing apparatus can stably seal the opening of the container for battery cells of various shapes. The manufacturing apparatus has versatility.

[0028] The temperature of the first hot plate is set to a first temperature, The temperature of the second hot plate may be set to a second temperature lower than the first temperature.

[0029] Since the first hot plate and the second hot plate are separate bodies, the temperature of the first hot plate and the temperature of the second hot plate can be optimized respectively.

[0030] Also, since the second hot plate for welding the edges of the exterior material has a relatively low temperature, the second hot plate can suppress overheating of the exterior material.

[0031] The pressing force of the first hot plate is set to a first pressing force, The pressing force of the second hot plate may be set to a second pressing force lower than the first pressing force.

[0032] Since the first hot plate and the second hot plate are separate bodies, the pressing force of the first hot plate and the pressing force of the second hot plate can be optimized respectively.

[0033] Also, since the second hot plate for welding the edges of the exterior material has a relatively low pressing force, the second hot plate can suppress overpressing of the exterior material.

[0034] The pressing and heating time of the first hot plate is set to a first time, The pressurization and heating time of the second heating plate may be set to a second time, which is shorter than the first time.

[0035] Since the first and second heating plates are separate components, the pressurizing and heating times for the first heating plate and the pressurizing and heating times for the second heating plate can be optimized independently.

[0036] Furthermore, since the second heating plate, which welds the edges of the exterior materials together, has a relatively short pressurization and heating time, it can suppress excessive pressurization and heating of the exterior materials.

[0037] In the aforementioned battery cell, the direction in which the first current collector connected to the negative electrode protrudes outward through the first opening of the container is the same as the direction in which the second current collector connected to the positive electrode protrudes outward through the second opening of the container. The battery cell manufacturing apparatus may further include a third heating plate that seals the edges of the container by applying pressure and heating in the stacking direction to the edges of the outer casing materials that overlap in the stacking direction, between the first and second openings which are adjacent in a direction perpendicular to the stacking direction.

[0038] The third heating plate, like the second heating plate, requires relatively low pressure and temperature to weld the edges of the overlapping exterior materials in the stacking direction. The battery cell manufacturing apparatus includes a third heating plate separate from the first and second heating plates, allowing for optimization of the pressure and temperature of the third heating plate. The aforementioned manufacturing apparatus can properly weld the battery cells during manufacturing and can simultaneously and stably seal both the first and second openings. [Effects of the Invention]

[0039] The aforementioned battery cell manufacturing apparatus can properly perform welding during the manufacturing of battery cells. [Brief explanation of the drawing]

[0040] [Figure 1] Figure 1 is a cross-sectional view of a battery cell. [Figure 2]Figure 2 is a disassembled perspective view of a battery cell. [Figure 3] Figure 3 shows the manufacturing equipment for battery cells. [Figure 4] Figure 4 shows the manufacturing state of battery cells when the number of electrode layers differs. [Figure 5] Figure 5 shows the manufacturing state of battery cells when the position of the peripheral edge of the container is different. [Figure 6] Figure 6 shows a manufacturing apparatus for producing battery cells with a first opening and a second opening arranged side by side. [Figure 7] Figure 7 shows a conventional battery cell manufacturing apparatus. [Modes for carrying out the invention]

[0041] The following describes an embodiment of a battery cell manufacturing apparatus with reference to the drawings. The battery cell manufacturing apparatus described here is illustrative.

[0042] (Battery cell structure) Figure 1 schematically shows the overall structure of battery cell 1. Figure 2 is an exploded perspective view of battery cell 1. More specifically, Figure 2 is a perspective view of the power generation element 2 of battery cell 1. Hereafter, the left-right direction in Figure 1 will be referred to as the X direction, the direction perpendicular to the plane of Figure 1 will be referred to as the Y direction, and the up-down direction in Figure 1 will be referred to as the Z direction. The Z direction corresponds to the stacking direction, which will be described later, and the Y direction corresponds to the direction perpendicular to the stacking direction.

[0043] The battery cell 1 is a secondary battery. The battery cell 1 is, for example, a lithium-ion battery. The battery cell 1 is a so-called pouch-type battery. The battery cell 1 comprises a power generation element 2 and a container 10. The container 10 is sealed with the power generation element 2 and electrolyte contained within it. The container 10 is made into a bag shape by folding one outer casing material 11 or by overlapping two outer casing materials 11 and sealing the edges together. The outer casing material 11 has a three-layer structure, for example, a metal layer sandwiched between resin layers. The metal layer is, for example, aluminum or stainless steel. The resin layer is, for example, polypropylene (PP) or polyethylene (PE).

[0044] The power generation element 2 has a first electrode sheet 3. The first electrode sheet 3 is, for example, a negative electrode sheet. The power generation element 2 also has a second electrode sheet 4. The second electrode sheet 4 is, for example, a positive electrode sheet. The first electrode sheet 3 and the second electrode sheet 4 overlap alternately. The number of first electrode sheets 3 and second electrode sheets 4 in the power generation element 2 is arbitrary. The power generation element 2 is an electrode stack. In the following, the direction in which the first electrode sheet 3 and the second electrode sheet 4 are stacked may be referred to as the stacking direction.

[0045] The first electrode sheet 3 has a current collector 31. The current collector 31 is a thin plate or foil extending in the X direction. The end of the current collector 31, that is, the left end in Figure 1, protrudes out of the container 10 through the left opening 12 of the container 10.

[0046] An active material is applied to the first and second surfaces of the current collector 31 located inside the container 10. The first surface is the upper surface of the current collector 31 in Figure 1, and the second surface is the lower surface of the current collector 31 in Figure 1. The active material forms the first electrode 32. The current collector 31 is connected to the first electrode 32 inside the container 10.

[0047] The first electrode sheet 3 has a separator 33. The separator 33 separates the first electrode 32 of the first electrode sheet 3 from the second electrode 42 of the second electrode sheet 4, which will be described later. The separator 33 is, for example, a porous material that allows ionic substances to pass through.

[0048] The separator 33 covers the surface of each of the two first electrodes 32 on the first electrode sheet 3. The separator 33 may be formed by attaching a film to the first electrodes 32. Alternatively, the separator 33 may be formed by drying a slurry applied to the first electrodes 32. The area of ​​the separator 33 may be the same as the area of ​​the first electrode sheet 3, or it may be larger than the area of ​​the first electrode sheet 3.

[0049] The second electrode sheet 4 has a current collector 41. The current collector 41 is a thin plate or foil extending in the X direction. The end of the current collector 41, that is, the right end in Figure 1, protrudes out of the container 10 through the right opening 13 of the container 10. The right opening 13 is the opposite opening to the left opening 12 in the X direction. Note that the protruding direction of the current collector 41 is not limited to the opposite direction of the protruding direction of the current collector 31.

[0050] An active material is applied to the first and second surfaces of the current collector 41 located inside the container 10. The active material forms the second electrode 42. The current collector 41 is connected to the second electrode 42 inside the container 10.

[0051] As mentioned above, the first electrode sheet 3 and the second electrode sheet 4 are stacked alternately. The first electrode 32 and the second electrode 42 are stacked inside the container 10 via the separator 33 in the stacking direction, that is, in the Z direction.

[0052] The left opening 12 of the container 10 is sealed with resin 5. Resin 5 is a sealing material. Resin 5 is located between the outer material 11 and the current collector 31, and between the current collectors 31. Similarly, the right opening 13 is sealed with resin 5. Resin 5 is located between the outer material 11 and the current collector 41, and between the current collectors 41.

[0053] Multiple current collectors 31 are not connected inside the container 10, but protrude individually outside the container 10. Similarly, multiple current collectors 41 are not connected inside the container 10, but protrude individually outside the container 10. Since the connection space for the current collectors 31 and 41 inside the container 10 can be eliminated, the area of ​​the first electrode 32 and the second electrode 42 can be increased by the amount of space saved. The battery cell 1 can have a high energy density.

[0054] (Method of manufacturing battery cells) The manufacturing method for the battery cell 1 follows the procedure below. First, a first electrode sheet 3 and a second electrode sheet 4 are prepared. As described above, the first electrode sheet 3 has a current collector 31, a first electrode 32, and a separator 33. The first electrode sheet 3 also has a resin 5 (see Figure 2). The resin 5 is located in the current collector 31 between the end of the current collector 31 and the first electrode 32. The resin 5 is pre-welded to the first and second surfaces of the current collector 31, respectively.

[0055] The second electrode sheet 4 includes a current collector 41, a second electrode 42, and a resin 5. The resin 5 of the second electrode sheet 4, like the resin 5 of the first electrode sheet 3, is located on the current collector 41 between the end of the current collector 41 and the second electrode 42. The resin 5 is pre-welded to the first and second surfaces of the current collector 41.

[0056] Next, as shown in Figure 2, the first electrode sheet 3 and the second electrode sheet 4 are stacked alternately. The first electrode 32 and the second electrode 42 overlap via a separator 33. The first electrode sheet 3 and the second electrode sheet 4 are stacked to form the power generation element 2. At this time, the first electrode sheet 3 and the second electrode sheet 4 are stacked in such a way that the current collector 31 of the first electrode sheet 3 and the current collector 41 of the second electrode sheet 4 protrude in opposite directions from each other.

[0057] In the current collector 31 of the first electrode sheet 3, resin 5 is located between the end of the current collector 31 and the power generation element 2. The resin 5 is aligned in the lamination direction. In the current collector 41 of the second electrode sheet 4, resin 5 is also located between the end of the current collector 41 and the power generation element 2. The resin 5 is aligned in the lamination direction.

[0058] Resin 5 is a thermoplastic resin. Resin 5 is selected from unoriented polypropylene (CPP), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), biaxially oriented polypropylene (OPP), polyethylene terephthalate (PET), or biaxially oriented nylon (ONY). Resin 5 and the resin layer of the exterior material 11 may be the same resin.

[0059] After the power generation element 2 is formed, the exterior material 11 is placed over the power generation element 2, as virtually shown in Figure 2. In Figure 2, the first edge 111 in the X direction of the exterior material 11, which is shaded, is located at the position of the resin 5 of the first electrode sheet 3. The second edge 112 in the X direction of the exterior material 11 is located at the position of the resin 5 of the second electrode sheet 4. Both edges of the exterior material 11 in the Y direction are located outside the edges of the power generation element 2.

[0060] Next, the edges of the exterior material 11 and the resin 5 are welded together. Figure 3 corresponds to the III-III cross-sectional view in Figure 2. Here, the manufacturing method of the battery cell 1 is explained using the welding of the resin 5 and the first edge 111 of the exterior material 11 at the left opening 12 as an example, but the welding of the resin 5 and the second edge 112 of the exterior material 11 at the right opening 13 is similar.

[0061] The manufacturing apparatus 9 for the battery cell 1 is a hot plate welding apparatus. The manufacturing apparatus 9 is equipped with a first hot plate 91. The first hot plate 91 is a hot plate that welds the resin 5 and the outer material 11 together. More specifically, the first hot plate 91 pressurizes and heats the first edge 111 of the outer material 11 and the resin 5 in the stacking direction at the position of the left opening 12 of the container 10. The width of the first hot plate 91 (width in the left-right direction of the paper in Figure 3) corresponds to the width of the left opening 12.

[0062] The first heating plate 91 is located on the outside of the upper exterior material 11 and on the outside of the lower exterior material 11, respectively, in the Z direction. The first heating plate 91 pressurizes the exterior material 11 and the resin 5 in the Z direction by hydraulic cylinders 911, 911 (see black arrows in Figure 3). The hydraulic cylinders 911, 911 extend in the Z direction. By extending the hydraulic cylinders 911, 911, the first heating plate 91 can pressurize the first edge 111 of the exterior material 11 and the resin 5 in the Z direction. The hydraulic cylinders 911, 911 are an example of a pressurizing mechanism that generates the pressure applied to the first heating plate 91. The dashed line in Figure 3 virtually shows the interface where the resin 5 of the first electrode sheet 3 are welded together.

[0063] The battery cell 1 has a large number of current collectors 31 and 41 stacked in the Z direction. A corner portion 18 is formed between the side of the opening 12 and the edge of the container 10 adjacent to the side in the Y direction.

[0064] The manufacturing apparatus 9 includes a second heating plate 92. The second heating plate 92 is a heating plate that welds the first edges 111 of the outer casing material 11 together. More specifically, the second heating plate 92 pressurizes and heats the first edges 111 of the outer casing material 11, which are overlapping in the Z direction, at least in the Z direction, on the side of the resin 5 at the left opening 12 of the container 10. The second heating plate 92 is located above the upper outer casing material 11 and below the lower outer casing material 11, respectively, in the Z direction. The second heating plate 92 is also located on each side of the first heating plate 91 in the Y direction. The manufacturing apparatus 9 includes a total of four second heating plates 92.

[0065] The second heating plate 92 has a first surface 921 and a second surface 922. The first surface 921 is a surface facing the Y direction and is the surface that contacts the side of the left opening 12. As will be described later, the first surface 921 presses the first edge 111 of the exterior material 11 toward the side of the stacked resin 5 in the Y direction. The second surface 922 is a surface facing the Z direction and is the surface that contacts the edge of the container 10. As will be described later, the second surface 922 presses the first edges 111 of the exterior material 11 toward each other in the Z direction.

[0066] The second heat plate 92 is independent of the first heat plate 91. The second heat plate 92 has a pressurizing mechanism separate from the first heat plate 91. That is, the pressurizing mechanism of the second heat plate 92 has a hydraulic cylinder 923. The extension direction of the hydraulic cylinder 923 is inclined with respect to the Z direction. The pressurizing direction of the second heat plate 92 is different from the pressurizing direction of the first heat plate 91.

[0067] More specifically, the extension direction of the hydraulic cylinder 923 is inclined toward the left opening 12 with respect to the Z direction. The first surface 921 of the second heat plate 92 presses the exterior material 11 toward the side of the left opening 12 as the hydraulic cylinder 923 extends. The second surface 922 of the second heat plate 92 presses the exterior material 11 toward each other in the Z direction as the hydraulic cylinder 923 extends.

[0068] The pressing force of the first heating plate 91 is set to the first pressing force. The first pressing force is a relatively high pressing force. The first heating plate 91 can sufficiently pressurize the multiple resins 5 and exterior materials 11 that are stacked in the Z direction.

[0069] The pressure applied by the second heating plate 92 is set to the second pressure. The second pressure is lower than the first pressure. The second heating plate 92 can appropriately pressurize the overlapping exterior materials 11 in the Z direction without applying excessive pressure.

[0070] The temperature of the first heat plate 91 is set to a first temperature, which is a relatively high temperature. Thermal energy from the high-temperature first heat plate 91 is transmitted through the exterior material 11, the resin 5, and the current collector 31 from the outside in the stacking direction towards the center. Each of the multiple resins 5 stacked in the Z direction receives the thermal energy and melts.

[0071] The temperature of the second heating plate 92 is set to a second temperature, which is lower than the first temperature. Thermal energy from the second heating plate 92 is transferred to the exterior material 11, and the resin on the back of the exterior material 11 melts due to the thermal energy.

[0072] The pressurization and heating time of the first heating plate 91 is set to the first time. The first time is a relatively long time. The first heating plate 91 can supply sufficient thermal energy to each of the multiple resins 5 and exterior materials 11 stacked in the Z direction.

[0073] The pressurization and heating time of the second heating plate 92 is set to the second time. The second time is shorter than the first time. The second heating plate 92 can suppress the supply of excessive thermal energy to the exterior material 11 that overlaps in the Z direction.

[0074] The manufacturing apparatus 9 welds different parts of the openings 12 and 13 of the battery cell 1 using the first heating plate 91 and the second heating plate 92. The pressure, temperature, and time of the first heating plate 91 can be optimized, as can the pressure, temperature, and time of the second heating plate 92. The manufacturing apparatus 9 can properly weld the battery cell 1 during manufacturing. Furthermore, since the manufacturing apparatus 9 equipped with the first heating plate 91 and the second heating plate 92 can simultaneously weld different parts of the openings 12 and 13 of the battery cell 1, it is possible to reduce the number of manufacturing steps.

[0075] Laminates formed by stacking multiple resins 5 may have large dimensional variations. Large dimensional variations may cause gaps to form between the resin 5 and the outer packaging material 11 in the Y or Z direction at the openings 12 and 13 of the container 10 when the resin 5 is welded by the manufacturing equipment 9. The more layers of resin 5 there are, the more difficult it becomes to properly weld the resin 5 and the outer packaging material 11 and stably seal the openings 12 and 13.

[0076] In contrast, in the manufacturing apparatus 9 described above, the first heating plate 91 can apply pressure to the exterior material 11 and the resin 5 in the Z direction independently of the second heating plate 92. Multiple layers of resin 5 and exterior material 11 stacked at the openings 12 and 13 are properly welded together.

[0077] Furthermore, the second heating plate 92 can move diagonally with respect to the Z direction. The first surface 921 of the second heating plate 92 can weld the outer packaging material 11 to the sides of the stacked resin 5 at the openings 12 and 13 without any gaps. Also, the second surface 922 of the second heating plate 92 can properly weld the edges of the outer packaging material 11 together. The second heating plate 92, which can move in a different direction from the first heating plate 91, together with the first heating plate 91 can suppress the formation of gaps at the openings 12 and 13 of the container 10 and stably seal the openings 12 and 13.

[0078] Thus, as shown in Figure 3, the opening of the container 10 (in this case, the left opening 12) is sealed by the welded resin 5. The manufacturing apparatus 9 can improve the sealing quality of the openings 12 and 13 of the container 10.

[0079] In the manufacturing apparatus 9, the relative movement of the first heating plate 91 with respect to the second heating plate 92 in the Z direction is configured to be variable. The manufacturing apparatus 9 can stably seal the openings 12 and 13 of the container 10 for battery cells 1 of various shapes.

[0080] For example, Figure 4 illustrates the manufacturing state of a battery cell 101 in which the number of stacked electrode sheets 3 and 4 is less than that of the battery cell 1 in Figure 3. The thickness T of the openings 12 and 13 of the container 10 is relatively thin. Since the relative movement of the first heating plate 91 is variable, it can be positioned to correspond to the thickness T of the openings 12 and 13, and can pressurize the first edge 111 of the outer material 11 and the resin 5 in the Z direction. The manufacturing apparatus 9 can stably seal the openings 12 and 13 of the container 10 even for battery cells 101 with different shapes.

[0081] Furthermore, Figure 5 illustrates, for example, the manufacturing state of a battery cell 102 in which the position in the Z direction of the joint between the edges of the exterior material 11 is different from that of battery cell 1 in Figure 3. It can be said that battery cell 102 has different thicknesses T of the openings 12 and 13 of the container 10. As mentioned above, thickness T is the distance in the Z direction from the upper end of the openings 12 and 13 to the edge of the exterior material 11. Since the relative movement amount of the first heating plate 91 with respect to the second heating plate 92 is variable, it can be positioned to correspond to the thickness T of the openings 12 and 13 and can pressurize the first edge 111 of the exterior material 11 and the resin 5 in the Z direction. In addition, the second heating plate 92 can pressurize the edges of the exterior material 11 that are overlapping in the Z direction on the side of the first heating plate 91 in the Z direction, and can also pressurize the exterior material 11 toward the side of the stacked resin 5 in the Y direction. The manufacturing apparatus 9 can reliably seal the openings 12 and 13 of the container 10, even for battery cells 102 with different shapes.

[0082] The manufacturing apparatus 9, which includes a first heating plate 91 and a second heating plate 92 that are independent of each other, can manufacture battery cells 1 of various shapes and is highly versatile.

[0083] (modified version) Figure 6 shows a modified example of the manufacturing apparatus 9. The manufacturing apparatus 9 in Figure 6 includes a third heating plate 93. In the battery cell 1 manufactured by the manufacturing apparatus 9 in Figure 6, the current collectors 31 and 41 protrude in the same direction. At the first end of the container 10 in the X direction, a first opening 14 from which the current collector 31 protrudes and a second opening 15 from which the current collector 41 protrudes are provided side by side in the Y direction. The container 10 has a welded portion between the first opening 14 and the second opening 15 where the first edges 111 of the exterior material 11, which overlap in the Z direction, are welded together.

[0084] In the manufacturing apparatus 9 of Figure 6, the third heating plate 93 is interposed, so the first heating plate 91 is separated into a first heating plate 91 corresponding to the first opening 14 and a first heating plate 91 corresponding to the second opening 15. However, the first heating plate 91 may be a single unit.

[0085] The third heating plate 93 pressurizes and heats the first edges 111 of the exterior materials 11, which are stacked in the stacking direction, in the Z direction between the first opening 14 and the second opening 15. The manufacturing apparatus 9 is equipped with a pressurizing mechanism for the third heating plate 93. The pressurizing mechanism is a hydraulic cylinder 931. The hydraulic cylinder 931 extends in the Z direction. By extending the hydraulic cylinder 931, the third heating plate 93 can pressurize the first edges 111 of the exterior materials 11 in the Z direction.

[0086] The third heating plate 93 is independent of the first heating plate 91 and the second heating plate 92. The pressure applied to the third heating plate 93 is set to the third pressure. The temperature of the third heating plate 93 is set to the third temperature. The pressurizing and heating time for the third heating plate 93 is set to the third time. The pressurizing, temperature, and time for the third heating plate 93 are optimized, respectively. Because the first heating plate 91, the second heating plate 92, and the third heating plate 93 are independent of each other, the manufacturing apparatus 9 can appropriately pressurize and heat different parts of the openings 14 and 15 of the container 10. The manufacturing apparatus 9 can stably seal the openings 14 and 15 of the container 10.

[0087] The hydraulic cylinder 923 mentioned above is an example of a pressurizing mechanism that generates pressure on the second heat plate 92. The pressurizing mechanism for the second heat plate 92 is not limited to the hydraulic cylinder 923. A known cam mechanism may also be used for the pressurizing mechanism of the second heat plate 92. The cam mechanism converts the vertical pressurizing force into a direction inclined with respect to the vertical. The cam mechanism allows the second heat plate 92 to move in a direction oblique to the Z direction.

[0088] The second heating plate 92 may be configured to move in the Z direction. [Explanation of Symbols]

[0089] 1 battery cell 10 containers 11 Exterior materials 111 First edge 112 Second edge 12 Left opening 13 Right opening 14. First opening 15. Second opening 18 Corner 3. First electrode sheet 31 Current collector 32 1st electrode 4. Second electrode sheet 41 Current collector 42 2nd electrode 5 resin 91 1st hot plate 92 2nd heating plate 921 Page 1 922 2nd page 93 Third heating plate

Claims

1. A battery cell manufacturing apparatus, The battery cell comprises a container housing a power generation element in which a plurality of electrodes are stacked in the stacking direction, a plurality of current collectors connected to the electrodes within the container, which are stacked in the stacking direction and protrude out of the container through the opening of the container, and a resin that seals the opening of the container by being welded to the current collectors between the stacked current collectors. The container having the opening is formed by welding together the edges of the outer materials that overlap in the stacking direction. A first heating plate seals the opening of the container by applying pressure and heating the outer material and the resin in the lamination direction at the position of the opening of the container. A second heating plate seals the edge of the container by applying pressure and heating to at least the stacking direction to the edges of the outer materials that overlap in the stacking direction, located on the side of the resin at the opening of the container. Equipped with, Battery cell manufacturing equipment.

2. In the battery cell manufacturing apparatus described in claim 1, A corner is formed between the side of the opening and the edge of the container. The first heating plate moves in the stacking direction, thereby pressurizing the exterior material and the resin in the stacking direction. The second heating plate has a first surface that is in contact with the side of the opening and a second surface that is in contact with the edge of the container, and by moving in an oblique direction toward the opening with respect to the stacking direction, it pressurizes the exterior material in a direction perpendicular to the stacking direction and in the stacking direction, respectively. Battery cell manufacturing equipment.

3. In the battery cell manufacturing apparatus according to claim 2, The relative movement of the first heating plate with respect to the second heating plate in the stacking direction is variable. Battery cell manufacturing equipment.

4. In a battery cell manufacturing apparatus according to any one of claims 1 to 3, The temperature of the first heating plate is set to a first temperature. The temperature of the second heating plate is set to a second temperature that is lower than the first temperature. Battery cell manufacturing equipment.

5. In a battery cell manufacturing apparatus according to any one of claims 1 to 3, The pressure applied to the first heating plate is set to the first pressure. The pressure applied to the second heating plate is set to a second pressure that is lower than the first pressure. Battery cell manufacturing equipment.

6. In a battery cell manufacturing apparatus according to any one of claims 1 to 3, The pressurization and heating time of the first heating plate is set to the first hour. The pressurization and heating time of the second heating plate is set to a second time that is shorter than the first time. Battery cell manufacturing equipment.

7. In the battery cell manufacturing apparatus described in claim 1, In the aforementioned battery cell, the direction in which the first current collector connected to the negative electrode protrudes outward through the first opening of the container is the same as the direction in which the second current collector connected to the positive electrode protrudes outward through the second opening of the container. The container further includes a third heating plate that seals the edge of the container by applying pressure and heating to the edges of the exterior materials that overlap in the stacking direction, between the first and second openings that are adjacent to each other in a direction perpendicular to the stacking direction. Battery cell manufacturing equipment.

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