Lamination methods, battery cores and lamination systems.

Abstract

What was revealed was the lamination method, the battery core, and the lamination system. The process includes: heating and pressing the long sheet material of the first batch; cutting the material. It is a long sheet of the first set to form the sheet of the first set: heating and compressing the material. This is a long sheet from the second set: Cutting the long sheet material from the second set to form the sheet shape of the second set: Arrange one plate of spoons from the second set and at least one plate of spoons from the first set, respectively. From bottom to top, to shape the battery core and compress the battery core.

Description

Lamination method, battery cell and lamination system

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on March 31, 2021, with application number 202110352049.3. The entire contents of this application are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of power battery manufacturing, for example, to a stacking method, a battery cell and a stacking system. Background Art

[0003] Laminated lithium batteries have been widely used in various fields. The assembly process of laminated cells generally consists of lamination, gluing, preheating, hot pressing, pre-soldering, and main welding. The preheating process heats the laminated cells to achieve uniform temperatures inside and outside the cells. The hot pressing process uses high pressure and heat to press the cell electrodes and separators together, which helps improve cell performance. However, the long preheating and hot pressing processes have become a bottleneck restricting the efficiency of the entire laminated cell assembly process. Furthermore, the need to preheat and hot press the entire cell increases the size and space occupied by the preheating and hot pressing equipment, increasing the factory area. Furthermore, to ensure the temperature between the center and the outside of the cell is consistent, preheating equipment must be installed before hot pressing. This increases the number of process steps, reducing cell production efficiency, increasing energy consumption, and raising costs.

[0004] Summary of the Invention

[0005] The present application provides a lamination method, a battery cell and a lamination system, which ensure the heating effect and reduce the temperature difference between the center and the outside of the battery cell. There is no need to set up a preheating process before pressing the battery cell, which reduces the process steps, improves the production efficiency of the battery cell, reduces energy consumption, and reduces costs.

[0006] A lamination method, comprising:

[0007] Heating and pressing the first unit strip;

[0008] Cutting the first unit strip to form a first unit sheet, wherein the first unit sheet includes a first diaphragm sheet, a first polar sheet, a second diaphragm sheet, and a second polar sheet distributed from top to bottom;

[0009] Heating and pressing the second unit strip;

[0010] Cutting the second unit strip to form a second unit sheet, wherein the second unit sheet includes a third diaphragm sheet, a first polarity sheet, and a fourth diaphragm sheet distributed from top to bottom;

[0011] stacking a second unit cell and at least one first unit cell in sequence from bottom to top to form a battery cell;

[0012] The battery cells are pressed together.

[0013] A battery cell is manufactured using the above-mentioned lamination method.

[0014] A lamination system configured to prepare the above-mentioned battery cell, the lamination system comprising a first lamination device configured to prepare a first unit cell and a second lamination device configured to prepare a second unit cell, the first lamination device comprising a first feeding assembly, a first heat sealing assembly, a first cutting assembly, and a first detection assembly; the second lamination device comprising a second feeding assembly, a second heat sealing assembly, a second cutting assembly, and a second detection assembly;

[0015] The first feeding assembly includes a first diaphragm belt roller, a first polar belt roller, a second diaphragm belt roller, and a second polar belt roller, wherein the first diaphragm belt roller is configured to supply a first diaphragm belt, the second diaphragm belt roller is configured to supply a second diaphragm belt, the first polar belt roller is configured to supply a first polar belt, and the second polar belt roller is configured to supply a second polar belt; the first feeding assembly also includes two first cutting knives, wherein the two first cutting knives are respectively configured to cut the first polar belt and the second polar belt to form a first polar sheet and a second polar sheet;

[0016] The first feeding assembly further includes four first dischargers, one first discharger is provided on both sides of the first diaphragm strip, and one first discharger is provided on both sides of the second diaphragm strip; the first dischargers are configured to perform corona treatment on the first diaphragm strip and the second diaphragm strip; the first feeding assembly further includes four first deviation correctors, the four first deviation correctors being configured to perform deviation correction operations on the first diaphragm strip, the second diaphragm strip, the first polarity strip, and the second polarity strip, respectively;

[0017] The first heat sealing assembly is placed downstream of the first feeding assembly and is configured to heat and press the first unit strip, and the first heat sealing assembly includes a first pre-pressing roller, a first heating element and a first hot pressing roller which are sequentially arranged along the conveying direction of the first unit strip; two first pre-pressing rollers are provided, which are respectively placed on both sides of the first unit strip and are configured to pre-press the first diaphragm strip, the second diaphragm strip, the first polar sheet and the second polar sheet in the first unit strip; the first heating element is a heating plate structure and is provided with two heating plates, which are respectively placed on both sides of the first unit strip and are configured to heat the first unit strip; two first hot pressing rollers are provided, which are respectively placed on both sides of the first unit strip and are configured to press the first diaphragm strip, the second diaphragm strip, the first polar sheet and the second polar sheet in the first unit strip, so that the first diaphragm strip, the second diaphragm strip, the first polar sheet and the second polar sheet form an integral strip;

[0018] The first heat-sealing assembly further comprises two first polyethylene terephthalate (PET) film laying assemblies; one first PET film laying assembly is arranged above the first unit strip and is configured to lay a top layer of PET film for the first unit strip, and the other first PET film laying assembly is arranged below the first unit strip and is configured to lay a bottom layer of PET film for the first unit strip; each first PET film laying assembly comprises a first PET film unwinding roller and a first PET film receiving roller, the first PET film unwinding roller is arranged upstream of the first pre-pressing roller, and the first PET film receiving roller is arranged downstream of the first hot pressing roller;

[0019] The first cutting assembly is disposed downstream of the first heat sealing assembly and is configured to cut the first unit strip to form the first unit sheet. The first cutting assembly includes a second cutting blade configured to cut the first unit strip at a gap between two adjacent first polar sheets along a length direction of the first diaphragm strip to form the first unit sheet.

[0020] The first detection assembly is placed downstream of the first cutting assembly and is configured to detect the first unit piece. The first detection assembly includes a first appearance detection member configured to detect the appearance of the first unit piece and a first short circuit detection member configured to detect whether the first unit piece is short-circuited.

[0021] The second feeding assembly includes a third diaphragm strip roller, a third polarity strip roller and a fourth diaphragm strip roller; the third diaphragm strip roller is configured to supply a third diaphragm strip, the fourth diaphragm strip roller is configured to supply a fourth diaphragm strip, and the third polarity strip roller is configured to supply the first polarity strip; the second feeding assembly also includes a third cutting knife, and the third cutting knife is configured to cut the first polarity strip to form the first polarity sheet; the second feeding assembly also includes four second dischargers, one second discharger is provided on each side of the third diaphragm strip, and one second discharger is provided on each side of the fourth diaphragm strip; the second discharger is configured to perform corona treatment on the third diaphragm strip and the fourth diaphragm strip; the second feeding assembly also includes three second deviation correctors, and the three second deviation correctors are respectively configured to perform deviation correction operations on the third diaphragm strip, the fourth diaphragm strip and the first polarity strip;

[0022] The second heat sealing assembly is placed downstream of the second feeding assembly and is configured to heat and press the second unit strip. The second heat sealing assembly includes a second pre-pressing roller, a second heating element and a second hot pressing roller which are sequentially arranged along the conveying direction of the second unit strip. Two second pre-pressing rollers are provided, which are respectively placed on both sides of the second unit strip and are configured to pre-press the third diaphragm strip, the fourth diaphragm strip and the first polar sheet in the second unit strip. The second heating element is a heating plate structure and is provided with two heating plates, which are respectively placed on both sides of the second unit strip and are configured to heat the second unit strip. Two second hot pressing rollers are provided, which are respectively placed on both sides of the second unit strip and are configured to press the third diaphragm strip, the fourth diaphragm strip and the first polar sheet in the second unit strip, so that the third diaphragm strip, the fourth diaphragm strip and the first polar sheet form an integral strip.

[0023] The second heat-sealing assembly further includes two second PET film laying assemblies; one second PET film laying assembly is arranged above the second unit strip and is configured to lay a top layer of PET film for the second unit strip, and the other second PET film laying assembly is arranged below the second unit strip and is configured to lay a bottom layer of PET film for the second unit strip; each second PET film laying assembly includes a second PET film unwinding roller and a second PET film receiving roller, the second PET film unwinding roller is arranged upstream of the second pre-pressing roller, and the second PET film receiving roller is arranged downstream of the second hot pressing roller;

[0024] The second cutting assembly is disposed downstream of the second heat sealing assembly and is configured to cut the second unit strip to form the second unit sheet. The second cutting assembly includes a fourth cutting blade configured to cut the second unit strip at a gap between two adjacent first polarity sheets along the length direction of the third diaphragm strip to form the second unit sheet.

[0025] The second detection component is placed downstream of the second cutting component and is configured to detect the second unit piece. The second detection component includes a second appearance detection member configured to detect the appearance of the second unit piece and a second short circuit detection member configured to detect whether the second unit piece is short-circuited. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG1 is a schematic structural diagram of a lamination method provided in an embodiment of the present application;

[0027] FIG2 is a flowchart of the steps of a lamination method provided in an embodiment of the present application;

[0028] FIG3 is a schematic structural diagram of a first unit cell provided in an embodiment of the present application;

[0029] FIG4 is a schematic structural diagram of a second unit cell provided in an embodiment of the present application;

[0030] FIG5 is a schematic structural diagram of a first film-making device provided in an embodiment of the present application;

[0031] FIG6 is a schematic structural diagram of a second film-making device provided in an embodiment of the present application;

[0032] FIG7 is a structural diagram of a stacking process of a lamination method provided in an embodiment of the present application;

[0033] FIG8 is a schematic structural diagram of a laminating tape in a lamination method provided in an embodiment of the present application;

[0034] FIG9 is a flowchart of the steps of another lamination method provided in an embodiment of the present application.

[0035] In the picture:

[0036] 10. First diaphragm strip material; 20. Second diaphragm strip material; 30. Third diaphragm strip material; 40. Fourth diaphragm strip material; 50. First polarity strip material; 60. Second polarity strip material; 70. First unit strip material; 80. Second unit strip material; 90. Battery cell; 901. First unit cell; 902. Second unit cell;

[0037] 1. First diaphragm; 2. Second diaphragm; 3. Third diaphragm; 4. Fourth diaphragm; 5. First polarity sheet; 6. Second polarity sheet; 7. Adhesive tape;

[0038] 100, first film-making equipment; 101, first diaphragm belt roller; 102, first polarity belt roller; 103, second diaphragm belt roller; 104, second polarity belt roller; 105, first cutting blade; 106, first discharge motor; 107, first deflection corrector; 108, first pre-pressing roller; 109, first heating element; 1010, first hot pressing roller; 1011, first PET film unwinding roller; 1012, first PET film receiving roller; 1013, second cutting blade; 1014, first appearance inspection component; 1015, first short-circuit inspection component;

[0039] 200, second film-making equipment; 201, third diaphragm belt roller; 202, third polarity belt roller; 203, fourth diaphragm belt roller; 204, third cutting blade; 205, second discharge motor; 206, second deflection corrector; 207, second pre-pressing roller; 208, second heating element; 209, second hot pressing roller; 2010, second PET film unwinding roller; 2011, second PET film receiving roller; 2012, fourth cutting blade; 2013, second appearance inspection unit; 2014, second short-circuit inspection unit;

[0040] 300. Image acquisition component. DETAILED DESCRIPTION

[0041] The technical solutions of the embodiments of the present application will be described below in conjunction with the accompanying drawings. The described embodiments are only part of the embodiments of the present application.

[0042] In the description of this application, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. A person of ordinary skill in the art will understand the meaning of the above terms in this application according to the circumstances.

[0043] In this application, unless otherwise specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0044] The technical solution of this application is explained below with reference to the accompanying drawings and through specific implementation methods.

[0045] This embodiment provides a lamination method. As shown in Figures 1 to 9, the lamination method includes:

[0046] S1. Heating and pressing the first unit strip 70.

[0047] S2. Cut the first unit strip 70 to form a first unit sheet 901. The first unit sheet 901 includes a first diaphragm sheet 1, a first polar sheet 5, a second diaphragm sheet 2, and a second polar sheet 6 distributed from top to bottom.

[0048] The first diaphragm 1 and the second diaphragm 2 are composed of a polyethylene or polypropylene base film, and both sides of the first diaphragm 1 and the second diaphragm 2 are coated with a uniform polyvinylidene fluoride (poly(1,1-difluoroethylene), PVDF) or ceramic layer. The thickness of the first diaphragm 1 and the second diaphragm 2 are both 5-20μ; the first polar plate 5 is based on a copper foil, and the first electrode layer is coated on both sides of the copper foil. The material of the first electrode layer includes graphite, silicon oxide, carboxymethyl cellulose, styrene-butadiene rubber, and polyacrylonitrile; the second polar plate 6 is based on an aluminum foil, and the second electrode layer is coated on both sides of the aluminum foil. The material of the second electrode layer includes lithium iron phosphate, lithium nickel cobalt manganese oxide, PVDF, and carbon nanotubes;

[0049] S3, heating and pressing the second unit strip 80.

[0050] The heating temperature is 50-120 degrees Celsius and the pressing pressure is 980-3920N.

[0051] S4. Cut the second unit strip 80 to form a second unit sheet 902. The second unit sheet 902 includes a third diaphragm sheet 3, a first polarity sheet 5, and a fourth diaphragm sheet 4 arranged from top to bottom.

[0052] S5. Stack a second unit cell 902 and at least one first unit cell 901 in sequence from bottom to top to form a battery cell 90.

[0053] S6. Press-fit the battery cells 90.

[0054] The pressing pressure is 49000-196000N.

[0055] In this embodiment, the first polarity and the second polarity are two opposite polarities. For example, if the first polarity is negative, the second polarity is positive. Then the first polarity sheet 5 is a negative electrode sheet, and the second polarity sheet 6 is a positive electrode sheet.

[0056] In the lamination method provided in this embodiment, when preparing the first and second unit sheets 901, 902, the first and second unit strips 70, 80 are preheated and pressed together. Subsequently, the residual heat of the first and second unit sheets 901, 902 can be used to directly press the battery cells 90 together. Only the first and second unit strips 70, 80 are heated, which reduces the thickness required for heating, reduces the size of the equipment and the space occupied, while ensuring the heating effect and reducing the temperature difference between the center and the outside of the battery cells 90. There is no need for a preheating step before pressing the battery cells 90 together, which reduces the number of process steps, improves the production efficiency of the battery cells 90, and reduces energy consumption and costs. Furthermore, by cutting and processing the first and second unit strips 70, 80, into the first and second unit sheets 901, the first and second unit strips 901, 902 can be processed simultaneously, saving processing time and preventing the qualified rate of the first unit sheet 901 from affecting the qualified rate of the second unit sheet 902. The two preparation processes are independent of each other. Moreover, the first unit sheet 901 places the electrode sheet at the bottom layer to avoid damage caused by friction between the diaphragm and the conveying structure such as the conveyor belt, thereby ensuring the integrity of the diaphragm, thereby avoiding contact between the positive and negative electrodes and ensuring safety. This embodiment directly uses the first unit sheet 901 and the second unit sheet 902 for lamination to form the battery cell 90, thereby improving the production efficiency of the lamination. By using the corona treatment of the diaphragm and the form of heating during the lamination process, the qualified rate of the battery cell 90 product is guaranteed, and the consistency of the performance of multiple battery cells 90 in batch production is improved. By setting the positive and negative electrode sheet composite sequence in which the outermost sides of the battery cell 90 are both negative electrode sheets, it is ensured that lithium ions can completely enter the negative electrode after being deintercalated from the positive electrode, the number of higher-cost positive electrode sheets is less than the number of negative electrode sheets, and the positive electrode sheets are fully utilized, and the production cost of the battery cell 90 is reduced. The present application ensures the protection of the risk of diaphragm scratches during the composite lamination process, thereby improving the safety performance of the battery cell 90.

[0057] 5 is a schematic structural diagram of a first film-making device provided in an embodiment of the present application, wherein the first film-making device 100 is configured to prepare a first unit sheet 901. The first film-making device 100 includes a first feeding assembly, a first heat-sealing assembly, and a first cutting assembly.

[0058] The first feeding assembly includes a first membrane strip roller 101, a first polarity strip roller 102, a second membrane strip roller 103, and a second polarity strip roller 104. The first membrane strip roller 101 is configured to supply a first membrane strip 10, the second membrane strip roller 103 is configured to supply a second membrane strip 20, the first polarity strip roller 102 is configured to supply a first polarity strip 50, and the second polarity strip roller 104 is configured to supply a second polarity strip 60. The first feeding assembly also includes two first cutting knives 105, which are configured to cut the first polarity strip 50 and the second polarity strip 60, respectively, to form a first polarity sheet 5 and a second polarity sheet 6.

[0059] The first feeding assembly also includes four first dischargers 106, one first discharger 106 is provided on both sides of the first diaphragm strip 10, and one first discharger 106 is provided on both sides of the second diaphragm strip 20. The first dischargers 106 can perform corona treatment on the first diaphragm strip 10 and the second diaphragm strip 20. The diaphragm strip used in this embodiment has double-sided adhesive tape, and the adhesive surface is a smooth surface. The first dischargers 106 turn the smooth adhesive surface into a rough surface, thereby improving the adhesion effect between the diaphragm strip and the electrode. The first feeding assembly also includes four first deviation correctors 107, which are respectively configured to perform deviation correction operations on the first diaphragm strip 10, the second diaphragm strip 20, the first polarity strip 50, and the second polarity strip 60, to ensure the conveying direction of the above four strips, so as to ensure that the four strips in the first unit strip 70 are arranged in a facing relationship, thereby avoiding the risk of short circuit caused by contact between the positive and negative poles and improving safety. The first and second diaphragm strips 10 and 20 are first passed through a first discharger 106 and then corrected by a first deflection corrector 107. The first polarity strips 50 and second polarity strips 60 are first corrected by the first deflection corrector 107 and then cut by two first cutting blades 105 to form first polarity sheets 5 and second polarity sheets 6. Figure 5 shows only two first dischargers 106.

[0060] The first heat sealing assembly is placed downstream of the first feeding assembly. The first heat sealing assembly is configured to heat and press the first unit strip 70. The first heat sealing assembly includes a first pre-pressing roller 108, a first heating element 109, and a first hot pressing roller 1010, which are sequentially arranged along the conveying direction of the first unit strip 70. There are two first pre-pressing rollers 108, which are respectively placed on both sides of the first unit strip 70. They are configured to pre-press the first diaphragm strip 10, the second diaphragm strip 20, the first polar sheet 5, and the second polar sheet 6 in the first unit strip 70, thereby avoiding the movement between the internal polar sheet and the diaphragm strip during the subsequent heating and pressing process of the first unit strip 70, thereby avoiding contact between the positive and negative poles and ensuring safety. The first heating element 109 is a heating plate structure and is provided with two heating plates. The two heating plates are respectively placed on both sides of the first unit strip 70 and are configured to heat the first unit strip 70 to increase the stickiness of the adhesive surface on the diaphragm strip. Two first hot pressing rollers 1010 are provided, one on each side of the first unit strip 70, and are configured to press the first diaphragm strip 10, the second diaphragm strip 20, the first polar sheet 5, and the second polar sheet 6 in the first unit strip 70, so that the first diaphragm strip 10, the second diaphragm strip 20, the first polar sheet 5, and the second polar sheet 6 form an integral strip, which is convenient for subsequent cutting and avoids contact between the positive and negative electrodes. In this embodiment, the first hot pressing roller 1010 has a heating function to ensure that the first unit strip 70 is always heated during the pressing process, thereby ensuring the stickiness of the adhesive surface of the diaphragm strip. Among them, the hot pressing roller is a related technology and will not be described in detail here.

[0061] The first heat-sealing assembly also includes two first polyethylene glycol terephthalate (PET) film laying assemblies. One of the first PET film laying assemblies is positioned above the first unit strip 70 and is configured to lay a top layer of PET film for the first unit strip 70. The other first PET film laying assembly is positioned below the first unit strip 70 and is configured to lay a bottom layer of PET film for the first unit strip 70. The PET film is configured to protect the first unit strip 70 during the heat-sealing process, thereby ensuring the qualified rate of the battery cell 90 products. In this embodiment, each first PET film laying assembly includes a first PET film unwinding roller 1011 and a first PET film receiving roller 1012. The first PET film unwinding roller 1011 is positioned upstream of the first pre-pressing roller 108, and the first PET film receiving roller 1012 is positioned downstream of the first hot pressing roller 1010.

[0062] The first cutting assembly is positioned downstream of the first heat sealing assembly and is configured to cut the first unit strip 70 to form the first unit sheet 901. The first cutting assembly includes a second cutting blade 1013, which is configured to cut the first unit strip 70 in the gap between two adjacent first polar sheets 5 along the length of the first diaphragm strip 10 to form the first unit sheet 901. The first cutting blade 105 and the second cutting blade 1013 are both related technologies and will not be described in detail here.

[0063] The first production device 100 further includes a first detection assembly, positioned downstream of the first cutting assembly, configured to inspect the first unit cell 901. The first detection assembly includes a first appearance detection member 1014 configured to detect the appearance of the first unit cell 901, and a first short circuit detection member 1015 configured to detect whether the first unit cell 901 is short-circuited. Both the first appearance detection member 1014 and the first short circuit detection member 1015 are related technologies and will not be described in detail herein.

[0064] FIG6 shows a second production apparatus 200 configured to produce a second unit sheet 902. The second production apparatus 200 is similar in structure to the first production apparatus 100. The first production apparatus 100 and the second production apparatus 200 are arranged on the same horizontal plane. The second production apparatus 200 includes a second feeding assembly, a second heat sealing assembly, and a second cutting assembly.

[0065] The second feeding assembly includes a third diaphragm strip roller 201, a third polarity strip roller 202, and a fourth diaphragm strip roller 203. The third diaphragm strip roller 201 is configured to feed the third diaphragm strip 30, the fourth diaphragm strip roller 203 is configured to feed the fourth diaphragm strip 40, and the third polarity strip roller 202 is configured to feed the first polarity strip 50. The second feeding assembly also includes a third cutting knife 204, which is configured to cut the first polarity strip 50 to form the first polarity sheet 5. The second feeding assembly also includes four second dischargers 205, one second discharger 205 is provided on each side of the third diaphragm strip 30, and one second discharger 205 is provided on each side of the fourth diaphragm strip 40. The second dischargers 205 are capable of performing corona treatment on the third diaphragm strip 30 and the fourth diaphragm strip 40. The diaphragm strip used in this embodiment is double-sided with adhesive, and the adhesive surface is smooth. The second discharge motor 205 roughens the smooth adhesive surface, improving the adhesion between the diaphragm strip and the electrode sheet. The second feed assembly also includes three second deflection correctors 206, which are configured to perform deflection correction operations on the third diaphragm strip 30, the fourth diaphragm strip 40, and the first polarity strip 50, respectively. This ensures the correct conveying direction of the three strips, ensuring that the three strips in the second unit strip 80 are aligned with each other. This avoids the risk of short circuits caused by contact between the negative electrode of the first unit sheet 901 and the positive electrode of the second unit sheet 902, thereby improving safety. The third diaphragm strip 30 and the fourth diaphragm strip 40 first pass through the second discharge motor 205 and then through the second deflection corrector 206. The first polarity strip 50 first passes through the second deflection corrector 206 and is then cut by the third cutting blade 204 to form the first polarity sheet 5. Only two second deflection correctors 205 are shown in Figure 6.

[0066] The second heat sealing assembly is positioned downstream of the second feeding assembly and is configured to heat and press the second unit strip 80. The second heat sealing assembly includes a second pre-pressing roller 207, a second heating element 208, and a second hot pressing roller 209, which are sequentially arranged along the conveying direction of the second unit strip 80. Two second pre-pressing rollers 207 are provided, one on each side of the second unit strip 80, and are configured to pre-press the third diaphragm strip 30, the fourth diaphragm strip 40, and the first polar sheet 5 within the second unit strip 80. This prevents movement between the internal polar sheet and the diaphragm strip during the subsequent heating and pressing process of the second unit strip 80, thereby avoiding the risk of short circuits caused by contact between the negative electrode in the first unit sheet 901 and the positive electrode in the second unit sheet 902, thereby ensuring safety. The second heating element 208 is a heating plate structure and is provided with two heating plates, one on each side of the second unit strip 80, and is configured to heat the second unit strip 80 and increase the stickiness of the adhesive surface on the diaphragm strip. Two second hot pressing rollers 209 are provided, one on each side of the second unit strip 80, and are configured to press the third diaphragm strip 30, the fourth diaphragm strip 40, and the first polarity sheet 5 within the second unit strip 80, so that the third diaphragm strip 30, the fourth diaphragm strip 40, and the first polarity sheet 5 form an integral strip, which is convenient for subsequent cutting and avoids contact between the positive and negative electrodes. In this embodiment, the second hot pressing roller 209 has a heating function to ensure that the second unit strip 80 is always heated during the pressing process, thereby ensuring the stickiness of the adhesive surface of the diaphragm strip. Among them, the hot pressing roller is related technology and will not be described in detail here.

[0067] The second heat-sealing assembly also includes two second PET film laying assemblies. One of the second PET film laying assemblies is positioned above the second unit strip 80 and is configured to lay a top layer of PET film for the second unit strip 80. The other second PET film laying assembly is positioned below the second unit strip 80 and is configured to lay a bottom layer of PET film for the second unit strip 80. The PET film is configured to protect the second unit strip 80 during the heat-sealing process, thereby ensuring the qualified rate of the battery cells 90. In this embodiment, each second PET film laying assembly includes a second PET film unwinding roller 2010 and a second PET film receiving roller 2011. The second PET film unwinding roller 2010 is positioned upstream of the second pre-pressing roller 207, and the second PET film receiving roller 2011 is positioned downstream of the second hot pressing roller 209.

[0068] The second cutting assembly is positioned downstream of the second heat sealing assembly and is configured to cut the second unit strip 80 to form a second unit sheet 902. The second cutting assembly includes a fourth cutting blade 2012, which is configured to cut the second unit strip 80 in the gap between two adjacent first polar sheets 5 along the length of the third diaphragm strip 30 to form the second unit sheet 902. The third cutting blade 204 and the fourth cutting blade 2012 are both related technologies and will not be described in detail here.

[0069] The second film-making device 200 also includes a second detection assembly, which is positioned downstream of the second cutting assembly. The second detection assembly is configured to detect the second unit piece 902. The second detection assembly includes a second appearance detection member 2013 configured to detect the appearance of the second unit piece 902, and a second short-circuit detection member 2014 configured to detect whether the second unit piece 902 is short-circuited. The second appearance detection member 2013 and the second short-circuit detection member 2014 are both related technologies and will not be described in detail herein.

[0070] In this embodiment, the first polarity is the negative electrode and the second polarity is the positive electrode, so the first polarity strip material 50 is the negative electrode strip material and the second polarity strip material 60 is the negative electrode strip material.

[0071] FIG9 is a flowchart of another lamination method provided by this embodiment. The lamination process is described below with reference to FIG1 to FIG9. The lamination process includes:

[0072] S1. Heating and pressing the first unit strip 70.

[0073] In step S1 of this embodiment:

[0074] S11 , pre-pressing the stacked first diaphragm strip 10 , the first polar sheet 5 , the second diaphragm strip 20 and the second polar sheet 6 to form a first unit strip 70 . Two first pre-pressing rollers 108 are used for pre-pressing.

[0075] The first polarity strip 50 and the second polarity strip 60 are first corrected by the first deflection corrector 107, and then cut by the first cutting knife 105 to form the first polarity sheet 5 and the second polarity sheet 6, which is convenient for cutting the first polarity strip 50 and the second polarity strip 60 according to the actual length requirements, thereby expanding the scope of application. Moreover, before being cut by the first cutting knife 105, they are corrected by the first deflection corrector 107, which ensures the accuracy of the shape and size of the pole pieces and the qualified rate of the battery cell 90. In this embodiment, in the first unit strip 70, a plurality of first polarity sheets 5 and a plurality of second polarity sheets 6 are arranged at intervals along the length direction of the first diaphragm strip 10, and the first diaphragm strip 10 and the second diaphragm strip 20 are parallel and extend in the same direction. The plurality of first polarity sheets 5 and the plurality of second polarity sheets 6 are arranged one by one in a facing relationship.

[0076] Before step S11, it also includes: S10, corona treatment of the first diaphragm strip 10 and the second diaphragm strip 20. The first discharge machine 106 is used to perform corona treatment on the first diaphragm strip 10 and the second diaphragm strip 20, which increases the roughness of the adhesive surface of the diaphragm strip, facilitates lamination with the electrode, and also improves the connection strength between the diaphragm and the electrode. After the corona treatment, the first deviation corrector 107 corrects the first diaphragm strip 10 and the second diaphragm strip 20 to ensure the position of the subsequent diaphragm, correct the change in the position of the diaphragm caused by the corona treatment, ensure that the diaphragm can cover the electrode, avoid contact between the positive and negative electrodes, and ensure safety. Among them, the corona voltage is 2.0-4.0KV.

[0077] S12. Heating the pre-pressed first unit strip 70. The first heating element 109 heats the pre-pressed first unit strip 70 to make the adhesive surface of the diaphragm within the first unit strip 70 sticky, facilitating connection to the electrode. The heating temperature is 50-120 degrees Celsius, and the pressing pressure is 980-3920 Newtons.

[0078] S13. Laminating the heated first unit strip 70. The heated first unit strip 70 is laminated to form a single strip, facilitating subsequent cutting. In step S13, the first unit strip 70 is laminated using a first hot pressing roller 1010. The first hot pressing roller 1010 has a heating function, ensuring that the first unit strip 70 is heated during the lamination process, thereby maintaining the adhesive surface of the diaphragm strip.

[0079] S2. Cut the first unit strip 70 to form a first unit sheet 901. The first unit sheet 901 includes a first diaphragm sheet 1, a first polar sheet 5, a second diaphragm sheet 2, and a second polar sheet 6 distributed from top to bottom.

[0080] The first unit strip 70 is cut into the first unit piece 901 using a second cutting knife 1013 . The second cutting knife 1013 is configured to cut the first unit strip 70 in the gap between two adjacent first polarity pieces 5 along the length direction of the first diaphragm strip 10 to form the first unit piece 901 .

[0081] S3, heating and pressing the second unit strip 80.

[0082] Step S3 includes:

[0083] S31 , pre-pressing and stacking the third diaphragm strip 30 , the first polar sheet 5 and the fourth diaphragm strip 40 to form a second unit strip 80 .

[0084] The first polarity strip 50 is first corrected by the second deflection corrector 206 before being cut by the third cutting blade 204 to form the first polarity segments 5. This facilitates cutting the first polarity strip 50 to the required length, expanding its applicability. Furthermore, the second deflection corrector 206 corrects the polarity segments before cutting by the third cutting blade 204, ensuring the accuracy of the polarity segment shape and size, and guaranteeing the qualified rate of the battery cells 90. In this embodiment, in the second unit strip 80, multiple first polarity segments 5 are arranged at intervals along the length of the third diaphragm strip 30. The third diaphragm strip 30 and the fourth diaphragm strip 40 extend parallel to each other and in the same direction.

[0085] Before step S31, it also includes: S30, corona treatment of the third diaphragm strip 30 and the fourth diaphragm strip 40. Similar to step S10, the third diaphragm strip 30 and the fourth diaphragm strip 40 are subjected to corona treatment using the second discharger 205, which increases the roughness of the adhesive surface of the diaphragm strip, facilitates lamination with the electrode, and also improves the firmness of the connection between the diaphragm and the electrode. After the corona treatment, the second deviation corrector 206 corrects the deviation of the third diaphragm strip 30 and the fourth diaphragm strip 40 to ensure the position of the subsequent diaphragm, correct the change in the position of the diaphragm caused by the corona treatment, ensure that the diaphragm can cover the electrode, avoid contact between the positive and negative electrodes, and ensure safety.

[0086] S32: Heating the pre-pressed second unit strip 80. The second heating element 208 is used to heat the pre-pressed second unit strip 80 to make the adhesive surface of the diaphragm in the second unit strip 80 sticky, facilitating connection with the electrode.

[0087] S33, pressing the heated second unit strip 80, pressing the heated second unit strip 80 to form the second unit strip 80 into an integral strip shape, which is convenient for subsequent cutting to form second unit sheets 902. In step S33, the second unit strip 80 is pressed using a second hot pressing roller 209. The second hot pressing roller 209 not only performs a pressing function but also a heat preservation function, further ensuring the adhesion of the diaphragm strip.

[0088] S4. Cut the second unit strip 80 to form a second unit sheet 902. The second unit sheet 902 includes a third diaphragm sheet 3, a first polarity sheet 5, and a fourth diaphragm sheet 4 arranged from top to bottom.

[0089] The second unit strip 80 is cut into a second unit piece 902 using a fourth cutting blade 2012 . The fourth cutting blade 2012 is configured to cut the second unit strip 80 in the gap between two adjacent first polarity pieces 5 along the length direction of the third diaphragm strip 30 to form the second unit piece 902 .

[0090] S5. Stack a second unit cell 902 and at least one first unit cell 901 in sequence from bottom to top to form a battery cell 90.

[0091] In this embodiment, a second unit cell 902 is first placed on the stacking platform, and first unit cells 901 are sequentially stacked on top of the second unit cell 902 to form a battery cell 90. Since the pole piece in the second unit cell 902 is the first polarity piece 5, the first unit cell 901 is placed with the second polarity piece 6 facing downward and toward the second unit cell 902, so that the first polarity piece 5 - the second polarity piece 6 - the first polarity piece 5 - the second polarity piece 6 are alternately arranged. The number of first unit cells 901 is not limited.

[0092] In step S4, each time the first unit cell 901 is stacked, the first unit cell 901 is also corrected by using an image acquisition component 300 positioned directly above the battery cell 90 to facilitate observation and correction of the position of the first unit cell 901. The image acquisition component 300 can be a charge coupled device (CCD) camera, etc., and is not limited here.

[0093] In step S5, a heating plate is installed below the second unit sheet 902. The heating temperature of the heating plate is 50-90 degrees Celsius. The installation of the heating plate can play a role in heat preservation. Because the first unit strip 70 and the second unit strip 80 are both heated during the pressing process, the first unit sheet 901 and the second unit sheet 902 retain residual heat. The installation of the heating plate can slow down the temperature drop of the first unit sheet 901 and the second unit sheet 902, facilitating the subsequent overall pressing of the battery cell 90. The heating plate is fixed to the lamination platform, and the second unit sheet 902 of the battery cell 90 is placed on the heating plate.

[0094] S6. Press-fit the battery cells 90.

[0095] The battery cell 90 is pressed together as a whole, forming a single unit for easy transport and storage. Furthermore, during the pressing process, the battery cell 90 is always placed on a heating plate, which provides insulation and ensures a secure connection between the electrode and the diaphragm. The device for pressing the battery cell 90 is related art and will not be described in detail here.

[0096] After step S6 , the process further includes: S7 , applying adhesive tape 7 to the outside of the battery cell 90 .

[0097] Adhesive tape 7 is wrapped around the outside of the battery cells 90, bundling the cells 90 into a single, integrated structure. This facilitates transport and transfer, ensures proper alignment between the electrode sheets within the cells 90, and guarantees a high yield rate. In this embodiment, adhesive tape 7 can be directly wrapped around the sidewalls of the cells 90 to bond the multiple electrode sheets and diaphragms to the tape 7. In other embodiments, the tape 7 can be divided into multiple sections, each of which is U-shaped, with two straight edges attached to the diaphragms at each end of the cells 90, and the connecting edge between the two straight edges attached to the side of the cells 90.

[0098] After step S7, the process further includes: S8, testing the battery cell 90. Performing a short circuit test and an external thickness test on the battery cell 90 as a whole. In other embodiments, other types of tests may be performed on the battery cell 90, which are not limited here.

[0099] Testing the battery cell 90 includes: testing the resistance value of the battery cell 90 , wherein the testing voltage is 50-300V and the testing time is 3-5s; testing the thickness of the battery cell 90 , wherein the testing pressure is 490-4900N; and testing the size of the battery cell 90 , wherein the width of the battery cell 90 is 50-200mm and the length of the battery cell 90 is 100-1500mm.

Claims

1. The lamination method consists of: heating and compressing the first set of long sheets (70); cutting the first set of long sheets (70) to form the first set sheet (901), in which the first set sheet (901) is composed of the first diaphragm sheet (1), the first polarized sheet (5), the second diaphragm sheet (2), and the second polarized sheet (6), which are distributed from top to bottom; heating and compressing the second set of long sheets (80); cutting the second set of long sheets (80) to form the second set sheet (902), in which the second set sheet (902) is composed of the third diaphragm sheet (3),1. The first polar plate (5) and the fourth diaphragm plate (4) are distributed from top to bottom; stacking one plate of the second series (902) and at least one plate of the first series (901) respectively from bottom to top to form the battery core (90) and compress the battery core (90).

2. The lamination method under claim 1 in which the heating plate is arranged below one plate of the second series (902).

3. The lamination method under claim 1 in which the heating and compression steps of the long sheet material of the first series (70) are combined. This includes: the compression of the first diaphragm long sheet material (10), the first polarized sheet (5), the second diaphragm long sheet material (20) and the second polarized sheet (6) which are stacked to form the first long sheet material (70); heating the first compressed long sheet material (70) and the compression of the first heated long sheet material (70).

4. The lamination method under claim 3, in which the compression step of the first heated long sheet material (70)Comprising: Compression of the first set of long sheets (70) by the first hot press roller (1010).

5. Lamination method according to claim 3, prior to the compression of the first diaphragm long sheet (10), the first polarized sheet (5), the second diaphragm long sheet (20) and the second polarized sheet (6) which are pre-assembled to form the first set of long sheets (70), which is further comprising: Corona treatment of the first diaphragm long sheet (10) and the second diaphragm long sheet (20).

6. Lamination method according to claim 1 in which the heating and compression steps of the second set of long sheets (80) are comprising: Compression of the third diaphragm long sheet (30),The lamination method under claim 6, in which the step of pressing the heated second set of long sheets (80) is included: pressing the second set of long sheets (80) by using a heated roller. Second (209)8. Lamination method according to claim 6. Prior to compression of the long sheet material of the third diaphragm (30), the first polarized sheet (5) and the long sheet material of the fourth diaphragm (40) which are stacked to form the long sheet material of the second set (80) which is further assembled with: Corona treatment of the long sheet material of the third diaphragm (30) and the long sheet material of the fourth diaphragm (40).

9. Any one of the lamination methods according to claims 1 through 8, after compression of the battery core (90),10. Lamination method according to claim 9, after the application of adhesive tape (7) on the exterior of the battery core (90), which includes: detection of the battery core (90).

11. Battery core constructed by any of the lamination methods according to claims 1 through 10.

12. Lamination system arranged to prepare the battery core according to claim 11, in which the lamination system includes the device used to prepare the first plate (10). 0) The equipment used to prepare the first set of plates (901) and the equipment used to prepare the second set of plates (200) are arranged to prepare the second set of plates (902) and the equipment used to prepare the first set of plates (100) are combined with the first set feeding assembly, the first set hot sealing assembly, the first set cutting assembly and the first set detection assembly: The equipment used to prepare the second set of plates (200) are combined with the second set feeding assembly, the second set hot sealing assembly,The second cutting assembly and the second detection assembly; the first feeding assembly consists of the first diaphragm long sheet material roller (10), the first pole long sheet material roller (102), the second diaphragm long sheet material roller (103), and the second pole long sheet material roller (104). The first diaphragm long sheet material roller (101) is arranged to feed the first diaphragm long sheet material (10), the second diaphragm long sheet material roller (103) is arranged to feed the second diaphragm long sheet material (20).The first pole long sheet material roller (102) is arranged to feed the first pole long sheet material (r0), and the second pole long sheet material roller (104) is arranged to feed the second pole long sheet material (60). The first feeding assembly is further equipped with two first-grade trimming knives (105), and two first-grade trimming knives (105) are arranged to trim the first pole long sheet material (50) and the second pole long sheet material (60), respectively, to form the first pole plate (5) and the second pole plate (6). The first feeding assembly is further equipped with four first-grade electric cutting knives (106).One first-stage (106) metal cutter is arranged on each side of the long sheet material of the first diaphragm (10) and one first-stage (106) metal cutter is arranged on each side of the long sheet material of the second diaphragm (20); the first-stage (106) metal cutter is arranged to perform corona treatment on the long sheet material of the first diaphragm (10) and the long sheet material of the second diaphragm (20): the first-stage feed assembly is further assembled with four first-stage (107) deflection correction devices and four first-stage (107) deflection correction devices are arranged to perform deflection treatment on the long sheet material of the first diaphragm (10), the long sheet material of the second diaphragm (20),The first polarized sheet material (R0) and the second polarized sheet material (60), respectively: the first hot-sealing assembly is arranged at the end of the first feeding assembly and is arranged to heat and compress the first sheet material (70), and the first hot-sealing assembly consists of two first pre-pressing rollers (108), two first heating elements (109), and two first hot-pressing rollers (1010), which are arranged in the conveying direction of the first sheet material (70); the two first pre-pressing rollers (108) are arranged on the two sides of the first sheet material (70), respectively, and are arranged to compress the first diaphragm sheet material (10), the second diaphragm sheet material (20), the first polarized sheet (5), and the second polarized sheet (6) before the first sheet material (70).The first two heating elements (109) have a plate heating structure and two heating plates are arranged on the two sides of the first set's long sheet material (70) respectively and are arranged to heat the first set's long sheet material (70). The first two hot press rollers (1010) are arranged on the two sides of the first set's long sheet material (70) and are arranged to compress the first set's long sheet material (10), the second set's long sheet material (20), the first polarized plate (5) and the second polarized plate (6) in the first set's long sheet material (70), until the first set's long sheet material (10), the second set's long sheet material (20),The first polarized sheet (5) and the second polarized sheet (6) form the entire ribbon: the first heat sealing assembly is further assembled with two first polyethylene glycol terephthalate (PET) film placement assemblies: one first PET film placement assembly is placed on top of the first long sheet material (70) and arranged to place the top PET film for the first long sheet material (70) and the remaining first PET film placement assembly is placed below the first long sheet material (70) and arranged to place the bottom PET film for the first long sheet material (70); each first PET film placement assembly is assembled with one first PET film dispensing roller (1011) and one first PET film dispensing roller (1012),The first PET film dispensing roller (1011) is positioned at the beginning of the first pre-pressing roller (108), and the first PET film dispensing roller (1012) is positioned at the end of the first hot-pressing roller (1010); the first cutting assembly is positioned at the end of the first hot-sealing assembly and is arranged to cut the long sheet material of the first assembly (70) to form the sheet of the first assembly (901); the first cutting assembly is integrated with the second trimming knife (103).It is arranged to cut the long sheet material of the first set (70) in the space between the two adjacent first-set terminal plates (5) in the length direction of the long sheet material of the first diaphragm (10) to form the first set plate (901); the first set detection assembly is arranged at the end of the first set cutting assembly and is arranged to detect the first set plate (901) and the first set detection assembly is combined with the first appearance detection component (1014) which is arranged to The first set's plate (901) and the first short-circuit detection component (1015) are arranged to detect whether the first set's plate (901) is short-circuited; the second set's feed assembly consists of the third diaphragm's long sheet material roller (201), the third terminal long sheet material roller (202), and the fourth diaphragm's long sheet material roller (203): the third diaphragm's long sheet material roller (201) is arranged to feed the third diaphragm's long sheet material (30).The long sheet material roller of the fourth diaphragm (203) is arranged to feed the long sheet material of the fourth diaphragm (40), and the long sheet material roller with poles of the third diaphragm (202) is arranged to feed the long sheet material with poles of the first diaphragm (50); the second feeding assembly is further assembled with a third trimming knife (204), the third trimming knife (204) is arranged to trim the long sheet material with poles of the first diaphragm (50) to form the long sheet with poles of the first diaphragm (5); the second feeding assembly is further assembled with four second electric cutting machines (205), one second electric cutting machine (205) is arranged on each side of the long sheet material of the third diaphragm (30), and one second electric cutting machine (205) is arranged on each side of the long sheet material of the fourth diaphragm (40).A second electrically charged metal cutter (205) is arranged to perform corona work on the long sheet material of the third diaphragm (30) and the long sheet material of the fourth diaphragm (40); the second feed assembly is further assembled with: two and three deviation correction devices (206) and two and three deviation correction devices (206) are arranged to perform deviation correction work on the long sheet material of the third diaphragm (30), the long sheet material of the fourth diaphragm (40) and the long sheet material of the first pole (50), respectively; a second hot-sealing assembly is arranged at the end of the second feed assembly to heat and compress the long sheet material of the second (80) and the second hot-sealing assembly is assembled with two second pre-pressing rollers (207),Two second heating elements (208) and two second hot press rollers (209) are arranged in the conveying direction of the second set of long sheet material (80); two second pre-press rollers (207) are arranged on the two sides of the second set of long sheet material (80) respectively and are arranged to press the long sheet material of the third diaphragm (30), the long sheet material of the fourth diaphragm (40) and the first pole plate (5) preceding the long sheet material of the second set (80); the heating elements The second set of two heating plates (208) has a heating plate structure and two heating plates are arranged on two sides of the long sheet material of the second set (80) respectively and are arranged to heat the long sheet material of the second set (80): the second set of two hot press rollers (209) are arranged on two sides of the long sheet material of the second set (80) and are arranged to press the long sheet material of the third diaphragm (30), the long sheet material of the fourth diaphragm (40) and the first pole plate (5) in the long sheet material of the second set (80),This causes the long sheet material of the third diaphragm (30), the long sheet material of the fourth diaphragm (40), and the first polarized sheet (5) to form the entire ribbon; the second heat sealing assembly is further assembled with two second PET film placement assemblies; one second PET film placement assembly is placed on top of the second long sheet material (80) and arranged to place the top PET film for the second long sheet material (80), and the remaining second PET film placement assembly is placed below the second long sheet material (80) and arranged to place the bottom PET film for the second long sheet material (80); each second PET film placement assembly is assembled with one second PET film dispensing roller (2010) and one second PET film dispensing roller (2011).The second PET film dispensing roller (2010) is positioned at the beginning of the second pre-pressing roller (207), and the second PET film dispensing roller (2011) is positioned at the end of the second hot press roller (209); the second cutting assembly is positioned at the end of the second hot sealing assembly and is arranged to cut the long sheet material of the second assembly (80) to form the sheet of the second assembly (902): the second cutting assembly is integrated with the fourth trimming knife (2012).It is arranged to cut the long sheet material of the second assembly (80) in the space between the two adjacent first-stage terminal plates (5) in the length direction of the long sheet material of the third diaphragm (30) to form the second assembly plate (902), and the second detection assembly is arranged at the end of the second cutting assembly and is arranged to detect the second assembly plate (902), and the second detection assembly consists of the second appearance detection component (2013) which is arranged to detect the appearance of the second assembly plate (902) and the second short-circuit detection component (2014) which is arranged to detect whether the second assembly plate (902) is short-circuited;

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