Method for manufacturing a battery cell

Abstract

The present invention suppresses the influence of heat on the power generation element during the manufacturing of a battery cell. In the manufacturing method of the battery cell (1), electrode sheets (3, 4) are stacked in the stacking direction to form a power generation element (2). The electrode sheets (3, 4) have electrodes (32, 42) located in a container (10) and current collectors (31, 41) connected to the electrodes in the container and protruding outward from the container opening (12, 13). At the location of the container opening, the resin (51) located between the stacked current collectors is pressurized and heated from the outside to the center side in the stacking direction. During the pressurization and heating of the resin, heat is promoted to move from the power generation element to the outside of the power generation element. Then, the resin is fused between the current collectors and the container opening is sealed.

Description

Technical Field

[0001] The technology disclosed herein relates to a method for manufacturing a single battery cell. Background Technology

[0002] Patent Document 1 describes a conventional laminated battery. A laminated battery is a battery in which an electrode body is housed within an outer casing. The laminated battery has a plurality of current collector terminals extending from the electrode body to the outer casing. These current collector terminals overlap with a thermoplastic resin. At the periphery of the outer casing, the resin is fused together and to the outer casing, thereby sealing the periphery of the outer casing from which the current collector terminals extend. In the laminated battery, each current collector terminal extends outward from the outer casing. Within the outer casing, the plurality of current collector terminals are not connected to each other. In the laminated battery, the space within the outer casing can be used to expand the electrode body. The structure of the laminated battery is advantageous for increasing the battery's energy density.

[0003] [Existing Technical Documents] [Patent Documents] [Patent Document 1] Japanese Patent Application Publication No. 2009-272161. Summary of the Invention

[0004] [The technical problem the invention aims to solve] The stacked battery is manufactured through a heat seal process. In the heat seal process, a heating plate, which serves as the energy supply source, is pressed in the overlapping direction, thereby causing the resin overlapping at the periphery of the outer component to fuse together.

[0005] Here, in the stacked battery, as previously described, the electrode body is enlarged in the outer casing. The electrode body is located near the periphery of the outer casing. During the heat sealing process, when the resin is heated by a heating plate, the temperature of the electrode body near the heating plate may rise excessively. If the temperature of the electrode body is too high, the separator of the electrode body will thermally shrink, which may cause a short circuit in the manufactured stacked battery.

[0006] The technology disclosed herein is used to suppress the effects of heat on power generation components during the manufacture of battery cells.

[0007] Technical means to solve technical problems The technology disclosed herein relates to a method for manufacturing a single battery cell. In this manufacturing method, Electrode sheets are stacked in a stacking direction to form a power generation element. The electrode sheets have electrodes located inside a container and current collectors connected to the electrodes inside the container and protruding outward from the opening of the container. At the opening of the container, the resin located between the stacked current collectors is pressurized and heated from the outside to the center in the stacking direction. During the pressurization and heating of the resin, heat is facilitated to move from the power generation element to the outside of the power generation element, and then... The resin is welded between the current collectors and the opening of the container is sealed.

[0008] In a battery cell manufactured using this method, a plurality of stacked current collectors protrude outwards through openings in the container. These current collectors are connected, for example, to electrodes of the same polarity. Inside the container, the current collectors are not connected to each other. This eliminates the need for connection spaces between the current collectors within the container. The power generation element, including the electrodes, can be expanded using the space inside the container. This battery cell structure can improve energy density.

[0009] The container opening is sealed with resin. The resin is, for example, a thermoplastic resin. During the manufacture of the battery cell, at the container opening, the stacked current collectors and the resin between them are pressurized and heated from the outside to the center in the stacking direction. For example, a pair of heating plates located on the outside of the container can be used to sandwich multiple resins in the stacking direction, with the heating plates supplying heat to the resin from the outside to the center in the stacking direction, thereby pressurizing and heating the resin. The resin is then fused between the current collectors, sealing the container opening.

[0010] Here, the power generation element extends to the vicinity of the container opening. During pressurization and heating, the resin sealing the opening may also cause the power generation element to be heated excessively.

[0011] In the manufacturing method described above, during the pressurization and heating of the resin, heat is facilitated to move from the power generation element to the outside of the element. This suppresses temperature rise in the power generation element. The power generation element is less susceptible to heat during the manufacturing of the battery cell. This also suppresses the occurrence of defects in the manufactured battery cell.

[0012] Alternatively, the electrode sheet may also have a diaphragm that is in contact with the electrode on the side opposite to the current collector and separates the individual electrodes in the stacking direction between the stacked electrode sheets.

[0013] Heating the separator may cause it to shrink. As mentioned earlier, the temperature rise of the power generation element is suppressed during the pressurization and heating of the resin, thus suppressing the thermal shrinkage of the separator. This also helps to prevent the generation of electrode short circuits in the manufactured battery cells.

[0014] Alternatively, the stacked resins can be sandwiched in the stacking direction by a pair of heating plates located outside the container, thereby pressurizing and heating the resins. During the pressurization and heating of the resin, the heat sink contacts the outer surface of the container at a position corresponding to the electrode of the power generation element, thereby promoting the movement of heat from the power generation element to the heat sink.

[0015] When the resin is pressurized and heated using a heating plate, the heat from the heating plate can also be easily transferred to the power generation element located near the resin.

[0016] To address this, the heat sink contacts the outer surface of the container at the position corresponding to the electrodes of the power generation element, thereby promoting heat movement from the power generation element to the heat sink. This helps to suppress the temperature rise of the power generation element. The position corresponding to the electrodes of the power generation element also corresponds to the position of the diaphragm of the power generation element. This helps to suppress the thermal contraction of the diaphragm.

[0017] Alternatively, the heat sink may be in contact with the outer surface of the container before the resin is pressurized and heated.

[0018] If the heat sink is in contact with the outer surface of the container beforehand, heat will rapidly begin to move from the power generation element to the heat sink after the resin is pressurized and heated. This effectively suppresses the temperature rise of the power generation element.

[0019] Alternatively, the heat sink can be cooled by a cooling device.

[0020] If the heat sink is cooled, it can further promote the movement of heat from the power generation element to the heat sink, thus further suppressing the temperature rise of the power generation element.

[0021] Alternatively, the resin can be preheated by the current collector before the pressurization and heating of the resin begin.

[0022] When multiple resins are sandwiched in a stacking direction using pairs of heating plates located on the outside of the container, and heat is supplied to the resins from the outside towards the center in the stacking direction, the heat is transferred sequentially from the resins on the outside to the resins on the center. Due to attenuation, the heat supplied to the resins located on the center side in the stacking direction is tends to be lower than the heat supplied to the resins located on the outside of the stacking direction.

[0023] In the manufacturing method, the resin is preheated by a current collector before pressurization and heating begin. Heat is efficiently supplied to the resin located at the center of the lamination direction via a current collector positioned at the center of the lamination direction.

[0024] The combination of resin preheating via the current collector and pressurization and heating from the outside of the stacking direction ensures a sufficient supply of heat to both the resin located on the outside and the resin located on the center side of the stacking direction. As a result, during the manufacture of the battery cell, all resin is fused along the entire stacking direction. This suppresses variations in the sealing strength of the container opening due to differences in location.

[0025] Preheating via the current collector improves the sealing quality of the container opening. However, heating the current collector also transfers heat to the power generation element. The temperature of the electrodes or diaphragm is prone to rise. Therefore, in the manufacturing method described above, promoting the movement of heat from the power generation element to the outside of the element effectively suppresses the temperature rise of the power generation element.

[0026] Alternatively, the preheating performed by the current collector can continue even after the pressurization and heating of the resin begins.

[0027] If preheating via the current collector is stopped during resin pressurization and heating, the resin temperature may drop due to heat dissipation through the current collector. By continuing preheating via the current collector even after resin pressurization and heating have begun, heat dissipation through the current collector can be suppressed. All resin is welded, stably sealing the container opening.

[0028] Alternatively, after the resin has been pressurized and heated, heat is continuously promoted to move from the power generation element to the outside of the power generation element.

[0029] After the resin pressurization and heating are completed, the temperature of the power generation element is also high. If the movement of heat from the power generation element to the outside of the element is continuously promoted, the temperature of the power generation element will decrease rapidly. This is to suppress the effects of heat on the power generation element during the manufacture of the battery cell.

[0030] [Invention Effects] In the method for manufacturing the battery cell, the effects of heat on the power generation element during the manufacturing of the battery cell can be suppressed. Attached Figure Description

[0031] Figure 1 It is a cross-sectional view of a single battery cell; Figure 2 The illustration shows a part of the manufacturing process of a single battery cell; Figure 3 The illustration shows a part of the manufacturing process of a single battery cell; Figure 4 The illustration shows a part of the manufacturing process of a single battery cell; Figure 5 The illustration shows a part of the manufacturing process of a single battery cell; Figure 6 The illustration shows a part of the manufacturing process for a single battery cell. Detailed Implementation

[0032] The following describes an implementation of the battery cell manufacturing process with reference to the accompanying drawings. The battery cell manufacturing process described here is an example.

[0033] (Structure of a single battery cell) Figure 1 The diagram schematically illustrates the overall structure of battery cell 1. Battery cell 1 is a secondary battery. Battery cell 1 is, for example, a lithium-ion battery.

[0034] The battery cell 1 is a so-called pouch-type battery. The battery cell 1 includes a power generation element 2 and a container 10. The container 10 is sealed while housing the power generation element 2 and electrolyte. The container 10 is a pouch-shaped object formed by folding one sheet of laminated material 11 or overlapping two sheets of laminated material 11. The laminated material 11 is, for example, a three-layer structure with 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).

[0035] 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 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 each other. 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 laminate. Hereinafter, the direction in which the first electrode sheet 3 and the second electrode sheet 4 are laminated is sometimes referred to as the lamination direction. The lamination direction is... Figure 1 And then... Figures 2-6 The top and bottom directions of the paper.

[0036] The first electrode 3 has a current collector body 31. The current collector body 31 is a thin sheet or foil extending in a direction orthogonal to the lamination direction. The end of the current collector body 31, i.e. Figure 1 The left end of the container protrudes out of the container 10 from the first opening 12 of the container 10.

[0037] An active material is coated onto the first and second surfaces of the current collector 31 located inside the container 10. The first surface... Figure 1 The middle is the upper surface of the current collector 31, and the second surface is... Figure 1 The lower surface of the current collector 31 is in the middle. The active material forms the first electrode 32. The current collector 31 is connected to the first electrode 32 inside the container 10.

[0038] The first electrode 3 has a diaphragm 33. The diaphragm 33 separates the first electrode 32 of the first electrode 3 from the second electrode 42 of the second electrode 4 (described later). The diaphragm 33 is, for example, a porous material that is permeable to ionic materials.

[0039] A diaphragm 33 covers the respective surfaces of the two first electrodes 32 in the first electrode sheet 3. The diaphragm 33 can be formed by attaching a membrane to the first electrode 32. Alternatively, it can be formed by drying the suspension coated on the first electrode 32. The area of ​​the diaphragm 33 can be the same as or larger than the area of ​​the first electrode sheet 3.

[0040] The second electrode plate 4 has a current collector 41. The current collector 41 is a thin plate or foil extending in a direction orthogonal to the lamination direction. The end of the current collector 41, i.e. Figure 1 The right end of the current collector 41 protrudes outward from the second opening 13 of the container 10. In a direction orthogonal to the stacking direction, the second opening 13 is the opposite of the first opening 12. The protruding direction of the current collector 41 is not limited to the opposite direction of the protruding direction of the current collector 31.

[0041] An active material is coated onto 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.

[0042] As previously described, 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 in the stacking direction inside the container 10 via a diaphragm 33.

[0043] The first opening 12 of container 10 is sealed with resin 5. Resin 5 is a sealing material. Resin 5 is located between the laminated material 11 and the current collector 31, and between each current collector 31. Similarly, the second opening 13 is sealed with resin 5. Resin 5 is located between the laminated material 11 and the current collector 41, and between each current collector 41.

[0044] A plurality of current collectors 31 are not connected inside the container 10, and each protrudes outward from the container 10. Similarly, a plurality of current collectors 41 are not connected inside the container 10, and each protrudes outward from the container 10. The connection space for the current collectors 31 and 41 can be omitted inside the container 10, thus allowing for a corresponding increase in the area of ​​the first electrode 32 and the second electrode 42. Figure 1 In this configuration, the end of the first electrode 3 is located near the openings 12 and 13 of the container 10. The battery cell 1 can improve energy density.

[0045] (Manufacturing method of battery cell) Next, refer to Figure 2 , 3 Sections 4, 5, and 6 describe the manufacturing method of battery cell 1. The manufacturing method of battery cell 1 is as follows: Figure 2 , 3The process is carried out in the order of 4, 5, and 6. Here, the manufacturing method of the battery cell 1 will be explained using the welding of resin in the first opening 12 as an example. The welding of resin in the second opening 13 is the same.

[0046] First, prepare the first electrode plate 3 and the second electrode plate 4. As mentioned earlier, the first electrode plate 3 has a current collector 31, a first electrode 32, and a diaphragm 33. The first electrode plate 3 also has a resin 51 (see reference). Figure 2 The resin 51 is located between the end of the current collector 31 and the first electrode 32 in the current collector 31. The resin 51 is pre-fused to the first surface and the second surface of the current collector 31, respectively.

[0047] The second electrode 4 has a current collector 41, a second electrode 42, and resin. The resin of the second electrode 4, like the resin 51 of the first electrode 3, is located in the current collector 41 between the end of the current collector 41 and the second electrode 42. The resin is pre-fused to the first and second surfaces of the current collector 41, respectively.

[0048] Next, as Figure 2 As shown, the first electrode plate 3 and the second electrode plate 4 are stacked alternately. Figure 3 As shown, the first electrode 32 and the second electrode 42 are overlapped by a diaphragm 33. Resin 51 is located between the current collectors 31 of the first electrode 3. The resin 51 is arranged in the stacking direction. Resin is also located between the current collectors 41 of the second electrode 4.

[0049] Resin 51 is a thermoplastic resin. Resin 51 is selected from cast polypropylene (CPP), low-density polyethylene (LDPE), linear low-density polyethylene (LDPE), high-density polyethylene (HDPE), oriented polypropylene (OPP), polyethylene terephthalate (PET), or biaxially oriented nylon (ONY).

[0050] After the first electrode sheet 3 and the second electrode sheet 4 are stacked to form the power generation element 2, the stacked material 11 covers the power generation element 2. For example... Figure 3 As shown, the edge of the laminated material 11 ( Figure 3 The position of the left edge (in the middle) corresponds to the position of the resin 51. In the stacking direction, the stacked material 11 is located on the outside relative to the outermost current collector 31. That is, in Figure 3 In the vertical direction, the stacked material 11 is located above the uppermost current collector 31 and below the lowermost current collector 31.

[0051] Next, cooling of the power generation element 2 begins. Cooling of the power generation element 2 is performed using heat sinks 63, 63. Heat sinks 63, 63 are in contact with the outer surface of the laminated material 11. Heat sinks 63, 63 are located at positions corresponding to the first electrode 32 and the diaphragm 33 of the power generation element 2. Heat sinks 63, 63 are in indirect contact with the power generation element 2 via the laminated material 11.

[0052] The lengths of the heat sinks 63, 63 in the direction orthogonal to the stacking direction can also be lengths corresponding to the lengths of the first electrode 32 and the diaphragm 33. The lengths of the heat sinks 63, 63 can also be shorter than the lengths of the first electrode 32 and the diaphragm 33.

[0053] Heat sinks 63, 63 are at least adjacent to resin 51. This is to promote the movement of heat from the power generation element 2 adjacent to resin 51 to heat sinks 63 when resin 51 is heated by the first heating plate 61 or the second heating plate 62 (described later).

[0054] The heat sink 63 is connected to the chiller 64. The heating medium circulates between the heat sink 63 and the chiller 64 (see reference). Figure 3 (Arrow). The refrigerator 64 cools the heat sink 63 via a heating medium. The refrigerator 64 is an example of a cooling device for cooling the heat sink 63. The cooling device is not limited to the refrigerator 64.

[0055] After the cooling of power generation element 2 begins, as Figure 4 As shown, preheating of resin 51 begins. Preheating of resin 51 is performed using a pair of first heating plates 61, 61. The pair of first heating plates 61, 61 sandwich a plurality of current collectors 31 in the stacking direction at the ends of the current collectors 31. The plurality of current collectors 31 overlap in the stacking direction. The high-temperature first heating plates 61, 61 heat the plurality of current collectors 31 in a state where they overlap in the stacking direction. Figure 4 As indicated by the hollow arrow, heat energy is supplied from the pair of first heating plates 61, 61 to resin 51 through current collector 31. Figure 4 In the diagram, only the current collector 31 at the center of the stacking direction is shown with an arrow, but heat energy is supplied to the resin 51 connected to the current collector 31 through each current collector 31. Each resin 51 heats up.

[0056] As the current collector 31 heats up, heat is transferred to the first electrode 32, the second electrode 42, and the diaphragm 33 of the power generation element 2. If the temperature of the diaphragm 33 is too high, the diaphragm 33 may thermally shrink.

[0057] In response, heat sink 63, as Figure 4 As indicated by the hollow arrow, it facilitates the movement of heat from the power generation element 2 to the heat sink 63, and suppresses the temperature rise of the diaphragm 33.

[0058] After the preheating of resin 51 begins, as follows Figure 5 As shown, the resin 51 arranged in the lamination direction is welded using a heating plate. The welding is performed using a pair of second heating plates 62, 62. The pair of second heating plates 62, 62 are located on the outer side of the laminated material 11, and apply pressure to the resin 51 arranged in the lamination direction from the outer side towards the center (see reference). Figure 4 (The gray arrow indicates the location of the first heating plate 61), and the resin 51 arranged in the stacking direction is heated. After the welding of the second heating plate 62, 62 begins, the preheating of the first heating plate 61, 61 continues.

[0059] The heat energy from the high-temperature second heating plates 62 is transferred from the outer side to the central side in the lamination direction through the laminated material 11, resin 51, and current collector 31. The resin 51 receives the heat energy and melts.

[0060] Here, as Figure 5 As indicated by the hollow arrow, due to attenuation, the heat energy supplied from the second heating plates 62, 62 to the resin 51 located at the center of the lamination direction is tends to be lower than the heat energy supplied to the resin 51 located at the outer side of the lamination direction. This may result in insufficient welding of the resin 51 located at the center of the lamination direction.

[0061] In this regard, the resin 51 located at the center of the lamination direction is preheated by the current collector 31. The resin 51 located at the center of the lamination direction is heated by the current collector 31, and heat energy is also supplied from the second heating plate 62 in the lamination direction. Sufficient heat energy is supplied to the resin 51 located at the center of the lamination direction.

[0062] In this way, sufficient heat energy is supplied to both the resin 51 located on the outer side of the lamination direction and the resin 51 located on the central side of the lamination direction. Figure 6 As shown, at the opening of container 10 (here, the first opening 12), the laminated material 11 and the current collector 31 are sealed by the fused resin 5, as well as between each current collector 31.

[0063] Here, during the heating plate welding of resin 51 using the second heating plates 62, 62, the heat sink 63 also facilitates heat transfer from the power generation element 2 to the heat sink 63. Since the power generation element 2 extends to the vicinity of resin 51, heat from the second heating plates 62, 62 is easily transferred to the diaphragm 33 of the power generation element 2. The heat sink 63 also suppresses the temperature rise of the diaphragm 33 during heating plate welding, thus suppressing thermal shrinkage of the diaphragm 33.

[0064] like Figure 6As shown, if the fusion of resin 51 is completed, the pressurization and heating of the second heating plates 62 and 62 will end, and the heating of the first heating plates 61 and 61 will end. If the first heating plates 61 and 61 separate from the current collector 31, sometimes the current collectors 31 will separate from each other in the stacking direction.

[0065] After the heating of the first heating plates 61 and 62 and the pressurization and heating of the second heating plates 62 and 62 are completed, the heat sink 63 continues to be in contact with the outer surface of the laminated material 11. Heat continues to move from the power generation element 2 to the heat sink 63. The temperature of the diaphragm 33 decreases rapidly. The diaphragm 33 is prevented from maintaining a high temperature. Thermal shrinkage of the diaphragm 33 is suppressed.

[0066] For example, after a specified time has elapsed since the heating of the first heating plates 61 and 62 and the pressurization and heating of the second heating plates 62 and 62 ended, the heat sink 63 separates from the outer surface of the laminated material 11.

[0067] As previously described, during the welding of the heating plates using the second heating plates 62, 62, the heat sink 63 is used to facilitate the transfer of heat from the power generation element 2 to the heat sink 63. This suppresses the temperature rise of the separator 33 of the power generation element 2, thus preventing thermal shrinkage of the separator 33. In the manufactured battery cell 1, short circuits of the electrodes 32, 42 are prevented. A battery cell 1 in which the plurality of current collectors 31 are not connected inside the container 10, and the areas of the first electrode 32 and the second electrode 42 are correspondingly enlarged, can be stably manufactured using the aforementioned manufacturing method.

[0068] Furthermore, in the aforementioned manufacturing method, before starting the heating plate welding using the second heating plates 62, 62, the resin 51 is preheated using the first heating plates 61, 61. Sufficient heat is supplied to both the resin 51 located at the center of the lamination direction and the resin 51 located at the outer side of the lamination direction.

[0069] Furthermore, if the resin 51 is preheated by the current collector 31 before the heating plate is welded, the time from the start of pressurization and heating from the outside of the lamination direction to the supply of sufficient heat energy to the resin 51 in the center of the lamination direction can be shortened. This can suppress the excessive supply of heat energy to the resin 51 on the outside of the lamination direction.

[0070] This prevents the sealing strength of the openings 12 and 13 of the container 10 from varying depending on the location. It also ensures stable fusion of all resin 51, thus improving the sealing quality of the openings 12 and 13 of the container 10.

[0071] Furthermore, the preheating of the first heating plates 61, 61 via the current collector 31 continues after the welding of the second heating plates 62, 62 begins. Therefore, during the welding of the second heating plates 62, 62, heat dissipation generated through the current collector 31 is suppressed. This suppresses the temperature drop of the resin 51 due to heat dissipation, thus enabling sufficient welding of the resin 51.

[0072] Furthermore, the preheating of the first heating plates 61, 61 via the current collector 31 ends simultaneously with the completion of the welding of the heating plates using the second heating plates 62, 62. If preheating continues via the current collector 31 after the welding of the heating plates has ended, excessive heat may be supplied to the resin 51. By ending the preheating via the current collector 31 simultaneously with the completion of the welding of the heating plates, excessive heat supply to the resin 51 can be prevented.

[0073] The preheating of the first heating plates 61, 61 through the current collector 31 can also be completed before the welding of the heating plates 62, 62 is finished.

[0074] Preheating of the resin 51 via the current collector 31 improves the sealing quality of the openings 12 and 13 of the container 10. On the other hand, heat is transferred to the power generation element 2 via the current collector 31, which is disadvantageous in terms of temperature rise of the diaphragm 33. Using the heat sink 63 promotes heat transfer from the power generation element 2 to the heat sink 63, thus suppressing temperature rise of the diaphragm 33 even when the resin 51 is preheated via the current collector 31.

[0075] Cooling using the heat sink 63 begins before the preheating of the resin 51 starts via the current collector 31. During the preheating of the resin 51, the temperature rise of the power generation element 2 is also suppressed, and if the heating plate welding begins, the heat sink 63 can rapidly cool the power generation element 2. This effectively suppresses the temperature rise of the power generation element 2.

[0076] The refrigerator 64 is then used to cool the heat sink 63, thus further promoting the movement of heat from the power generation element 2 to the heat sink 63. This further effectively suppresses the temperature rise of the power generation element 2.

[0077] (Variation example) The temperatures of the first heating plate 61 and the second heating plate 62 can be the same or different. By setting the temperature and heating period of the first heating plate 61 and the temperature and heating period of the second heating plate 62 separately, multiple resins 51 can be appropriately fused together. Controlling the preheating of the first heating plate 61 and the fusion of the heating plate 62 separately can improve the sealing quality of the openings 12 and 13 of the container 10.

[0078] In addition, in the aforementioned method for manufacturing the battery cell 1, the first heating plates 61, 61 are heated while a plurality of current collectors 31 are stacked in the stacking direction. However, the first heating plates 61, 61 may also selectively heat the current collector 31 located at the center side in the stacking direction.

[0079] Furthermore, in the aforementioned method for manufacturing the battery cell 1, the preheating of the resin 51 using the first heating plates 61, 61 can be omitted.

[0080] In addition to heating plate welding using the second heating plate 62, energy can also be supplied to the resin 51 from the outer side towards the center side in the lamination direction, for example, by vibration welding, ultrasonic welding, or high-frequency welding, thereby welding the resin 51. In all these welding methods, even with energy attenuation during welding, the manufacturing method described above can adequately weld the resin located on the center side in the lamination direction by combining resin preheating via a current collector.

[0081] The cooling device for heat sink 63 can also be omitted. The heat sink may, for example, have heat sink fins. A heat sink with heat sink fins can be cooled by a fan or by natural cooling.

[0082] Furthermore, in the structure that facilitates the movement of heat from the power generation element 2 to the outside of the power generation element 2, the disclosed technology does not exclude the omission of the heat dissipation plate 63 that contacts the outer surface of the laminated material 11.

[0083] [Numbering Explanation] 1. Battery cell 10 containers 12 First opening 13 Second opening 3. Electrode 1 31 Current collector 32 First Electrode 33 Diaphragm 4. Second electrode plate 41 Current collector 42 Second electrode 5. Resin 51 Resin 61 First heating plate 62 Second heating plate 63 Heat sink 64. Refrigeration unit (cooling device)

Claims

1. A method for manufacturing a battery cell, wherein in the method for manufacturing a battery cell, Electrode sheets are stacked in a stacking direction to form a power generation element. The electrode sheets have electrodes located inside a container and current collectors connected to the electrodes inside the container and protruding outward from the opening of the container. At the opening of the container, pressure and heat are applied to the resin located between the stacked current collectors from the outer side towards the center in the stacking direction. During the pressurization and heating of the resin, heat is facilitated to move from the power generation element to the outside of the power generation element, and then... The resin is welded between the current collectors and the opening of the container is sealed.

2. The method for manufacturing a single battery cell according to claim 1, characterized in that: The electrode sheet also has a diaphragm that is in contact with the electrode on the side opposite to the current collector and that separates the individual electrodes in the stacking direction between the stacked electrode sheets.

3. The method for manufacturing a single battery cell according to claim 1, characterized in that: The stacked resins are sandwiched in the stacking direction by a pair of heating plates located outside the container, thereby pressurizing and heating the resins. During the pressurization and heating of the resin, the heat sink is in contact with the outer surface of the container at a position corresponding to the electrode of the power generation element, thereby promoting the movement of heat from the power generation element to the heat sink.

4. The method for manufacturing a single battery cell according to claim 3, characterized in that: The heat sink contacts the outer surface of the container before the resin is pressurized and heated.

5. The method for manufacturing a single battery cell according to claim 3 or 4, characterized in that: The heat sink is cooled by a cooling device.

6. The method for manufacturing a single battery cell according to claim 1, characterized in that: Before pressurizing and heating the resin, the resin is preheated by the current collector.

7. The method for manufacturing a single battery cell according to claim 6, characterized in that: Preheating via the current collector continues after the pressurization and heating of the resin begins.

8. The method for manufacturing a single battery cell according to claim 1, characterized in that: After the resin is pressurized and heated, heat continues to move from the power generation element to the outside of the power generation element.

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