Hot pressing equipment, battery production system, battery cells, battery assembly, and electrical equipment.

Abstract

This application provides a hot pressing device, a battery production system, a battery cell, a battery device, and an electrical device. The hot pressing device is used to hot press an electrode assembly. The electrode assembly includes tabs that protrude along a first direction. The hot pressing device includes a driving member, a lower hot pressing member, and an upper hot pressing member. The upper and lower hot pressing members are arranged opposite to each other. At least one of the upper and lower hot pressing members is connected to the driving member and configured to move closer to or further away from each other under the drive of the driving member. At least one of the upper and lower hot pressing members includes a plate body and a compaction structure. The compaction structure is located on the side of the plate body facing the electrode assembly. The compaction structure has at least one pair of openings arranged opposite to each other along the first direction. The two openings in the pair extend towards the central region of the compaction structure in the first direction. The plate body covers at least a portion of the openings and is used to press against the electrode assembly through the openings. This application can improve the capacity retention rate of the battery cell.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a hot pressing device, a battery production system, a battery cell, a battery device, and an electrical device. Background Technology

[0002] Battery cells are widely used in electronic devices such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools, etc.

[0003] In the development of battery technology, improving the capacity retention rate of individual battery cells is a research direction. Summary of the Invention

[0004] This application provides a hot pressing device, a battery production system, a battery cell, a battery device, and an electrical device that can improve the capacity retention rate of the battery cell.

[0005] This application provides a hot pressing device for hot pressing an electrode assembly. The electrode assembly includes a tab that protrudes along a first direction. The hot pressing device includes a driving member, a lower hot pressing member, and an upper hot pressing member. The upper and lower hot pressing members are disposed opposite to each other. At least one of the upper and lower hot pressing members is connected to the driving member and configured to move closer to or further away from each other under the drive of the driving member. At least one of the upper and lower hot pressing members includes a plate body and a compaction structure. The compaction structure is located on the side of the plate body facing the electrode assembly. The plate body is used to generate heat, and the compaction structure is used to press against the electrode assembly. The compaction structure has at least one pair of openings disposed opposite to each other along the first direction. The two openings in the pair extend toward the central region of the compaction structure in the first direction. The plate body covers at least part of the openings and is used to press against the electrode assembly through the openings.

[0006] In the above technical solution, the hot pressing device of this embodiment provides a compaction structure on the upper hot pressing member and / or the lower hot pressing member. The compaction structure has a pair of openings arranged opposite to each other along the first direction, and the two openings extend toward the central region of the compaction structure in the first direction. In this way, the two electrode components corresponding to the two openings are not compacted, forming two exhaust channels. The gas generated in the central region of the electrode components in the first direction is discharged through the two exhaust channels, thereby reducing the impact of bubbles on the negative electrode sheet of the battery cell, reducing problems such as purple spots and lithium plating, improving the interface of the battery cell, and increasing the capacity retention rate of the battery cell.

[0007] In some embodiments, the compaction structure has multiple pairs of openings, which are spaced apart along a second direction, and the first and second directions intersect.

[0008] In the above technical solution, multiple pairs of openings are provided to increase the number of exhaust channels distributed in the second direction and improve the uniformity of exhaust from the electrode assembly.

[0009] In some embodiments, at least one pair of openings is located in the central region of the compaction structure in the second direction, where the first and second directions intersect.

[0010] In the above technical solution, at least one pair of openings are provided in the central region of the compaction structure in the second direction to improve the exhaust effect of the electrode assembly in the central region where it intersects in the second direction and the first direction.

[0011] In some embodiments, the compaction structure includes at least two first compaction portions and one second compaction portion. The two first compaction portions are spaced apart along a second direction and connected by a second compaction portion. The two first compaction portions and the second compaction portion enclose a pair of openings, and the first direction and the second direction intersect.

[0012] In the above technical solution, this embodiment forms a pair of openings by enclosing two first compaction parts and one second compaction part. In this way, by setting the size of the second compaction part along the first direction, a good venting effect can be achieved on the central area of ​​the electrode assembly in the first direction under the premise of compaction.

[0013] In some embodiments, the number of first compaction portions is greater than two, the number of second compaction portions is at least two, the plurality of first compaction portions and the plurality of second compaction portions are arranged sequentially at intervals along the second direction, any two adjacent first compaction portions are connected through the second compaction portions, and the plurality of first compaction portions and the plurality of second compaction portions surround to form multiple pairs of openings arranged at intervals along the second direction.

[0014] In the above technical solution, multiple first compaction parts and multiple second compaction parts are set to form multiple pairs of openings. The multiple pairs of openings are spaced apart along the second direction. In this way, the electrode assembly can form more exhaust channels, thereby increasing the number of exhaust channels distributed in the second direction and improving the uniformity of exhaust from the electrode assembly.

[0015] In some embodiments, there are two first compaction sections and one second compaction section. The dimension of the first compaction section along the second direction is W1, and the dimension of the second compaction section along the second direction is W2. W1 and W2 satisfy: W1≤W2.

[0016] In the above technical solution, the size of the second compaction part is set to be greater than or equal to the size of the first compaction part, so as to form a wider exhaust channel and improve the exhaust effect of the central area of ​​the electrode assembly.

[0017] In some embodiments, W1, W2 and W3 satisfy: 1 / 4W3≤W1≤W2≤1 / 2 W3.

[0018] In the above technical solution, the values ​​of W1 and W2 are limited to be greater than or equal to 1 / 4 W3 to improve the venting effect of the electrode assembly; the values ​​of W1 and W2 are limited to be less than or equal to 1 / 2 W3 so that the dimensions of the first compaction part 322 and the second compaction part 323 are more balanced along the second direction Y, thereby forming a better compaction effect.

[0019] In some embodiments, the two openings that form a pair are mirror-image arranged, and / or the two first compaction sections are mirror-image arranged.

[0020] In the above technical solution, the two paired openings are mirror-imaged to improve the uniformity of venting in the upper and lower parts of the counter electrode assembly. The two first compaction sections are mirror-imaged to improve the uniformity of compaction in the left and right regions of the counter electrode assembly.

[0021] In some embodiments, the size of the opening along the first direction is h1, and the size of the compaction structure along the first direction is h2, where h1 and h2 satisfy: 35% ≤ h1 / h2 ≤ 45%.

[0022] In the above technical solution, the value of h1 / h2 is limited to greater than or equal to 35% to form a larger exhaust channel in the first direction, thereby improving the exhaust effect on the central region of the electrode assembly; the value of h1 / h2 is limited to less than or equal to 45% to improve the compaction effect on the central region of the electrode assembly in the first direction.

[0023] In some embodiments, h1 and h2 satisfy: 38% ≤ h1 / h2 ≤ 42%.

[0024] In the above technical solution, the value of h1 / h2 is further limited to greater than or equal to 38% to form a larger exhaust channel in the first direction, thereby further improving the exhaust effect on the central region of the electrode assembly; the value of h1 / h2 is further limited to less than or equal to 42% to further improve the compaction effect on the central region of the electrode assembly in the first direction.

[0025] In some embodiments, the plate body and the compaction structure are integrally formed.

[0026] In the above technical solution, the plate body and the compaction structure are integrally formed, so the relative positional relationship between the plate body and the compaction structure is more accurate and the connection is more secure.

[0027] In some embodiments, the compaction structure is adhered to the plate body.

[0028] In the above technical solution, the compaction structure is pasted onto the plate body. In this way, the required size of the compaction structure can be pasted according to actual needs. For example, the overall size of the compaction structure or the size of the opening can be adjusted, thereby improving the applicability of the hot pressing device.

[0029] In some embodiments, the projection of the compaction structure onto the plate body along a third direction is located within the plate body, and the third direction is parallel to the arrangement direction of the plate body to the compaction structure.

[0030] In the above technical solution, the projection of the compaction structure onto the plate body along a third direction is located within the plate body, so that the heat generated by the plate body can be distributed throughout the entire compaction structure, and it is also convenient to set up the compaction structure.

[0031] In some embodiments, the hot pressing device further includes a pressure sensor, a first temperature sensor, and a second temperature sensor. The upper hot pressing member is provided with a pressure sensor and a first temperature sensor, and the lower hot pressing member is provided with a second temperature sensor. The pressure sensor is used to measure the pressure between the upper hot pressing member and the electrode assembly, the first temperature sensor is used to measure the temperature of the upper hot pressing member, and the second temperature sensor is used to measure the temperature of the lower hot pressing member.

[0032] In the above technical solution, a pressure sensor, a first temperature sensor, and a second temperature sensor are set up to monitor the pressure and temperature parameters during the hot pressing process, thereby achieving accurate monitoring of pressure and temperature in the hot pressing process.

[0033] Secondly, this application also provides a battery production system, including the hot pressing device and the forming device described above. The forming device is used to wind or stack positive electrode sheets, negative electrode sheets and separators to form an electrode assembly.

[0034] Thirdly, embodiments of this application also provide a battery cell, including a housing and an electrode assembly, the electrode assembly being located inside the housing, the electrode assembly being configured to be hot-pressed by a hot-pressing device as described above, the surface of the electrode assembly having indentations corresponding to at least a portion of the compaction structure, the indentations surrounding areas forming regions corresponding to paired openings.

[0035] Fourthly, embodiments of this application also provide a battery device, including the battery cell described above.

[0036] Fifthly, embodiments of this application also provide an electrical device, including the battery device described above, which is used to provide electrical energy. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the structure of a battery production system provided in some embodiments of this application;

[0039] Figure 2 This is a schematic diagram of the structure of the hot pressing device and electrode assembly provided in some embodiments of this application;

[0040] Figure 3 A schematic diagram of the upper hot pressing component in a hot pressing device provided in some embodiments of this application;

[0041] Figure 4 Another structural schematic diagram of the upper hot pressing component in the hot pressing device provided in some embodiments of this application;

[0042] Figure 5 This is a partial structural schematic diagram of a hot pressing device provided in some embodiments of this application;

[0043] Figure 6 This is a schematic diagram of the structure of a battery cell provided in some embodiments of this application;

[0044] Figure 7 This is a schematic diagram of the structure of a battery device provided in some embodiments of this application;

[0045] Figure 8 The diagram shows the structural features of a vehicle provided in some embodiments of this application.

[0046] The reference numerals in the accompanying drawings for the specific embodiments are as follows:

[0047] 100. Battery production system; 200. Hot pressing device; 300. Molding device; 400. Preheating device; 500. Pre-pressing device; 600. Electrode assembly; 610. Tab; 620. Dent; 700. Battery cell; 710. Casing; 800. Battery assembly; 810. Battery cell assembly; 820. Housing; 900. Vehicle; 910. Controller; 920. Motor;

[0048] 1. Driving components;

[0049] 2. Lower hot-pressed parts;

[0050] 3. Upper hot press component; 31. Plate body; 32. Compaction structure; 321. Opening; 322. First compaction section; 323. Second compaction section;

[0051] 4. Pressure sensor;

[0052] 5. First temperature sensor;

[0053] 6. Controller;

[0054] X, first direction; Y, second direction; Z, third direction. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0056] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0057] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0058] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0059] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0060] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0061] In this application, "multiple" means two or more (including two).

[0062] In this application, the battery cell may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell, a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc., and the embodiments of this application are not limited thereto. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited thereto.

[0063] A single battery cell includes electrode components and an electrolyte. The electrode components include a positive electrode, a negative electrode, and a separator. The battery cell primarily functions by the movement of metal ions between the positive and negative electrodes. The positive electrode includes a positive current collector and a positive active material layer, which is coated on the surface of the positive current collector. The positive current collector includes a positive electrode coating area and a positive electrode tab connected to the coating area. The coating area is coated with the positive active material layer, while the tab is not. Taking a lithium-ion battery cell as an example, the positive current collector can be made of aluminum, and the positive active material layer includes the positive active material, which can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode sheet includes a negative current collector and a negative active material layer, the negative active material layer being coated on the surface of the negative current collector. The negative current collector includes a negative electrode coating area and a negative electrode tab connected to the negative electrode coating area. The negative electrode coating area is coated with the negative active material layer, while the negative electrode tab is not coated with the negative active material layer. The material of the negative current collector can be copper, and the negative active material layer includes negative active material, which can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0064] A battery cell typically consists of an electrode assembly and a casing. Before being installed in the casing, the electrode assembly needs to undergo a hot pressing process, which involves using an upper and lower hot pressing plate to press the electrode assembly into a compact whole in order to improve the performance of the battery cell.

[0065] Research has revealed that during the formation stage, the central region of the electrode assembly generates a large amount of gas in the height direction. Since the entire electrode assembly is in a compacted state, the gas generated in the central region cannot be discharged from the electrode assembly in time. This leads to problems such as bubble-like purple spots and lithium plating on the negative electrode sheet, affecting the interface of the battery cell and causing a decrease in the capacity retention rate of the battery cell.

[0066] In view of this, this application provides a hot pressing device, which provides a compaction structure on an upper hot pressing member and / or a lower hot pressing member. The compaction structure has at least two openings facing away from each other along a first direction, and the openings extend toward the central region of the compaction structure in the height direction. In this way, the electrode assembly corresponding to the opening is not completely compacted, and the gas is discharged through the loose part that is not completely compacted, thereby reducing the impact of air bubbles on the negative electrode sheet of the battery cell, improving the interface of the battery cell, and improving the capacity retention rate of the battery cell.

[0067] Figure 1 This is a schematic diagram of the structure of a battery production system 100 provided in some embodiments of this application.

[0068] like Figure 1 As shown, the battery production system 100 includes a forming device 300 and a hot pressing device 200. The forming device 300 is used to wind or stack positive electrode sheets, negative electrode sheets and separators to form an electrode assembly 600.

[0069] For example, the battery production system 100 also includes an electrode coating apparatus for coating active material on at least one side of the current collector.

[0070] For example, the battery production system 100 also includes a drying device located downstream of the electrode coating device, which is used to dry the current collector coated with active material to form a dried electrode.

[0071] For example, the battery production system 100 also includes a preheating device 400, which includes a heating furnace for heating the electrode assembly 600. The preheating device 400 is located upstream of the hot pressing device 200. Optionally, the electrode assembly 600 is placed in the heating furnace for heating for 300s-600s to maintain the temperature of the electrode assembly 600 at a preset temperature.

[0072] For example, the battery production system 100 also includes a pre-pressing device 500, which includes an upper pressure plate, a lower pressure plate, and a driving mechanism. The upper and lower pressure plates are disposed opposite to each other. The lower pressure plate is used to support the electrode assembly 600, and the driving mechanism is connected to the upper pressure plate and drives the upper pressure plate to press down the electrode assembly 600. The pre-pressing device 500 is located upstream of the preheating device 400.

[0073] Figure 2 This is a schematic diagram of the structure of the hot pressing device and electrode assembly provided in some embodiments of this application. Figure 3 This is a schematic diagram of the upper hot pressing component in a hot pressing device provided in some embodiments of this application.

[0074] like Figure 2 and Figure 3 As shown, this application also provides a hot pressing device 200 for hot pressing an electrode assembly 600. The electrode assembly 600 includes a tab 610, which protrudes along a first direction X. The hot pressing device 200 includes a driving member 1, a lower hot pressing member 2, and an upper hot pressing member 3. The upper hot pressing member 3 and the lower hot pressing member 2 are disposed opposite to each other. At least one of the upper hot pressing member 3 and the lower hot pressing member 2 is connected to the driving member 1 and configured to move closer to or further away from each other under the drive of the driving member 1. At least one of the upper hot press member 3 and the lower hot press member 2 includes a plate body 31 and a compaction structure 32. The compaction structure 32 is located on the side of the plate body 31 facing the electrode assembly 600. The plate body 31 is used to generate heat, and the compaction structure 32 is used to press against the electrode assembly 600. The compaction structure 32 is provided with at least a pair of openings 321 arranged opposite to each other along the first direction X. The two pairs of openings 321 extend toward the central region of the compaction structure 32 in the first direction X. The plate body 31 covers at least part of the openings 321 and is used to press against the electrode assembly 600 through the openings 321.

[0075] In this embodiment, the tab 610 protruding along the first direction X means that the tab 610 and the non-tab portion of the electrode assembly 600 are arranged along the first direction X. Specifically, the positive and negative tabs can extend from the same side of the electrode assembly 600 or from opposite sides.

[0076] For example, the plate body 31 is provided with a resistance wire or resistance rod to generate heat.

[0077] In this embodiment, the pressure can be direct contact or indirect contact but still generate force. For example, the compaction structure 32 can be in direct contact with the electrode assembly, or the two can be in direct contact.

[0078] In this embodiment, the compaction structure 32 is provided with at least one pair of openings 321 arranged opposite to each other along the first direction X. The two openings 321 extend toward the central region of the compaction structure 32 in the first direction X. The central region of the compaction structure 32 in the first direction X refers to the region where the center line L1 of the compaction structure 32 in the first direction X is located, which is also the region where the center line of the electrode assembly 600 excluding the tab 610 is located approximately in the first direction X.

[0079] In this embodiment, the areas of the two paired openings 321 can be the same or different; their shapes can be the same or different.

[0080] In this embodiment, the pair of openings 321 can be located in the central region of the compaction structure 32 in the second direction Y, or in other regions of the compaction structure 32 in the second direction Y. The second direction Y intersects with the first direction X, and further, the second direction Y is perpendicular to the first direction X.

[0081] In this embodiment, the upper hot press 3 and the lower hot press 2 can both be provided with a compaction structure 32. For example, the pressure applied to the electrode assembly 600 by the upper hot press 3 and the lower hot press 2 ranges from 8 MPa to 10 MPa.

[0082] In this embodiment, the plate body 31 covers at least a portion of the opening 321 and is used to press against the electrode assembly 600 through the opening 321. That is, the projection of the plate body 31 on the compaction structure 32 along the arrangement direction of the plate body 31 to the compaction structure 32 covers at least a portion of the opening 321, and the portion of the plate body 31 covering the opening 321 acts as a pressure against the electrode assembly 600.

[0083] Optionally, the plate body 31 covers the entirety of each opening 321.

[0084] The hot pressing device 200 of this embodiment provides a compaction structure 32 on the upper hot pressing member 3 and / or the lower hot pressing member 2. The compaction structure 32 has openings 321 arranged opposite to each other along the first direction X, and the two pairs of openings 321 extend toward the central region of the compaction structure 32 in the first direction X. In this way, the two parts of the electrode assembly 600 corresponding to the two openings 321 are not compacted, forming two exhaust channels. The gas generated in the central region of the electrode assembly 600 in the first direction X is discharged through the two exhaust channels, thereby reducing the impact of bubbles on the negative electrode sheet of the battery cell, reducing problems such as purple spots and lithium plating, improving the interface of the battery cell, and improving the capacity retention rate of the battery cell.

[0085] Figure 4 This is another structural schematic diagram of the upper hot pressing component in the hot pressing device provided in some embodiments of this application.

[0086] Please see Figure 4 In some embodiments, the compaction structure 32 is provided with multiple pairs of openings 321, which are spaced apart along the second direction Y, and the first direction X and the second direction Y intersect.

[0087] In this embodiment, the number of multiple pairs of openings 321 can be two, three, four, or five, etc.

[0088] Optionally, the first direction X and the second direction Y are perpendicular.

[0089] Multiple pairs of openings 321 are provided to increase the number of exhaust channels distributed in the second direction Y, thereby improving the uniformity of exhaust from the electrode assembly 600.

[0090] In some embodiments, at least one pair of openings 321 is located in the central region of the compaction structure 32 in the second direction Y, where the first direction X and the second direction Y intersect.

[0091] In this embodiment, the central region of the compaction structure 32 in the second direction Y refers to the region where the center line L2 of the dimension of the compaction structure 32 in the second direction Y is located, which roughly corresponds to the region where the center line of the dimension of the electrode assembly 600 in the second direction Y is located.

[0092] Optionally, the first direction X and the second direction Y are perpendicular.

[0093] At least one pair of openings 321 are provided in the central region of the compaction structure 32 in the second direction Y to improve the exhaust effect of the electrode assembly 600 in the central region where the second direction Y and the first direction X intersect.

[0094] In some embodiments, the compaction structure 32 includes at least two first compaction portions 322 and one second compaction portion 323. The two first compaction portions 322 are spaced apart along the second direction Y and connected by the second compaction portion 323. The two first compaction portions 322 and the second compaction portion 323 surround to form a pair of openings 321. The first direction X and the second direction Y intersect.

[0095] In this embodiment, the second compaction portion 323 is located in the central region of the compaction structure 32 in the first direction X. Optionally, a second compaction portion 323 is located in the central region of the compaction structure 32 in the second direction Y.

[0096] Optionally, the first direction X and the second direction Y are perpendicular.

[0097] The two first compaction portions 322 in this embodiment can have the same shape or different shapes.

[0098] In this embodiment, the dimension of the first compaction part 322 in the second direction Y can be greater than, less than or equal to the dimension of the second compaction part 323 in the second direction Y.

[0099] Optionally, the first compaction part 322 facing the electrode assembly 600 is a rectangle with rounded corners, and the second compaction part 323 facing the electrode assembly 600 is a strip.

[0100] In this embodiment, two first compaction parts 322 and one second compaction part 323 are arranged to form a pair of openings 321. In this way, by setting the size of the second compaction part 323 along the first direction X, the central region of the electrode assembly 600 in the first direction X can play a good role in venting under the premise of compaction.

[0101] In other embodiments, the two first compaction portions 322 are connected by two second compaction portions 323.

[0102] Please continue reading. Figure 4 In some embodiments, the number of first compaction portions 322 is greater than two, and the number of second compaction portions 323 is at least two. The plurality of first compaction portions 322 and the plurality of second compaction portions 323 are arranged sequentially at intervals along the second direction Y. Any two adjacent first compaction portions 322 are connected through the second compaction portions 323. The plurality of first compaction portions 322 and the plurality of second compaction portions 323 surround and form a plurality of pairs of openings 321 arranged at intervals along the second direction Y.

[0103] In this embodiment, the number of first compaction portions 322 is one more than the number of second compaction portions 323. For example, there are three first compaction portions 322 and two second compaction portions 323; or there are four first compaction portions 322 and three second compaction portions 323.

[0104] In this embodiment, any two adjacent first compaction sections 322 are connected by a second compaction section 323.

[0105] Optionally, multiple first compaction sections 322 are arranged at equal intervals.

[0106] Multiple first compaction sections 322 and multiple second compaction sections 323 are provided to form multiple pairs of openings 321. The multiple pairs of openings 321 are spaced apart along the second direction Y. In this way, the electrode assembly 600 can form more exhaust channels, thereby increasing the number of exhaust channels distributed in the second direction Y and improving the uniformity of exhaust from the electrode assembly 600.

[0107] In some embodiments, there are two first compaction portions 322 and one second compaction portion 323. The dimension of the first compaction portion 322 along the second direction Y is W1, and the dimension of the second compaction portion 323 along the second direction Y is W2. W1 and W2 satisfy: W1≤W2.

[0108] In this embodiment, two first compaction portions 322 and one second compaction portion 323 are arranged to form two openings 321.

[0109] In this embodiment, the dimensions of the two first compaction portions 322 along the second direction Y can be the same or different.

[0110] The size of the second compaction section 323 is set to be greater than or equal to the size of the first compaction section 322 to form a wider exhaust channel and improve the exhaust effect in the central region of the electrode assembly 600.

[0111] In some embodiments, W1, W2 and W3 satisfy: 1 / 4W3≤W1≤W2≤1 / 2W3.

[0112] Optionally, the value of W1 can be 1 / 4W3, 3 / 8W3, or 1 / 2 W3.

[0113] Optionally, the value of W2 can be 1 / 4W3, 3 / 8W3, or 1 / 2 W3.

[0114] The values ​​of W1 and W2 are limited to be greater than or equal to 1 / 4 W3 to improve the venting effect of the electrode assembly 600; the values ​​of W1 and W2 are limited to be less than or equal to 1 / 2 W3 to make the dimensions of the first compaction part 322 and the second compaction part 323 more balanced along the second direction Y, thereby forming a better compaction effect.

[0115] In some embodiments, the two openings 321 that form a pair are mirror-mounted, and / or the two first compaction portions 322 are mirror-mounted.

[0116] In this embodiment, mirroring refers to having the same shape and size.

[0117] The two paired openings 321 are mirrored to improve the uniformity of venting in the upper and lower parts of the counter electrode assembly 600. The two first compaction sections 322 are mirrored to improve the uniformity of compaction in the left and right areas of the counter electrode assembly 600.

[0118] In some embodiments, the size of the opening 321 along the first direction X is h1, and the size of the compaction structure 32 along the first direction X is h2, where h1 and h2 satisfy: 35% ≤ h1 / h2 ≤ 45%.

[0119] Optionally, the value of h1 / h2 can be 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, or 45%.

[0120] The value of h1 / h2 is limited to greater than or equal to 35% to form a larger exhaust channel in the first direction X, thereby improving the exhaust effect in the central region of the electrode assembly 600; the value of h1 / h2 is limited to less than or equal to 45% to improve the compaction effect in the central region of the electrode assembly 600 in the first direction X.

[0121] In some embodiments, h1 and h2 satisfy: 38% ≤ h1 / h2 ≤ 42%.

[0122] The value of h1 / h2 is further restricted to greater than or equal to 38% to form a larger exhaust channel in the first direction X, thereby further improving the exhaust effect in the central region of the electrode assembly 600; the value of h1 / h2 is further restricted to less than or equal to 42% to further improve the compaction effect in the central region of the electrode assembly 600 in the first direction X.

[0123] In some embodiments, the plate body 31 and the compaction structure 32 are integrally formed.

[0124] In this embodiment, the plate body 31 and the compaction structure 32 can be injection molded as one piece, die-cast or cast as one piece, or 3D printed as one piece.

[0125] By integrally molding the plate body 31 and the compaction structure 32, the relative positional relationship between the plate body 31 and the compaction structure 32 is more accurate, and the connection is more secure, so it will hardly fall off.

[0126] In some embodiments, the compaction structure 32 is adhered to the plate body 31.

[0127] In this embodiment, the compaction structure 32 can be a business card paper structure, which is pasted onto the board body 31.

[0128] The compaction structure 32 is attached to the plate body 31. In this way, the compaction structure 32 of the required size can be attached according to actual needs. For example, the overall size of the compaction structure 32 or the size of the opening 321 can be adjusted, thereby improving the applicability of the hot pressing device 200.

[0129] In some embodiments, the projection of the compaction structure 32 along the third direction Z onto the plate body 31 is located within the plate body 31, and the third direction Z is parallel to the arrangement direction of the plate body 31 to the compaction structure 32.

[0130] In this embodiment, the projection of the compaction structure 32 along the third direction Z onto the plate body 31 is located inside the plate body 31. That is, the projection of the plate body 31 along the third direction Z onto the compaction structure 32 covers the compaction structure 32, and the area of ​​the plate body 31 facing the electrode assembly 600 is greater than the area of ​​the compaction structure 32 facing the electrode assembly 600.

[0131] Optionally, the first direction X, the second direction Y, and the third direction Z are all perpendicular to each other.

[0132] The projection of the compaction structure 32 along the third direction Z onto the plate body 31 is located within the plate body 31, so that the heat generated by the plate body 31 can be distributed throughout the entire compaction structure 32, and it is also convenient to set up the compaction structure 32.

[0133] Optionally, the plate body 31 protrudes from the compaction structure 32 in a circular arrangement along its own extension direction. That is, the plate body 31 surrounds the compaction structure 32 along the third direction Z and is projected onto the plate body 31 in a circular arrangement.

[0134] Optionally, the electrode assembly 600 is a wound electrode assembly, and the compaction structure 32 is used to avoid the bending area of ​​the wound electrode assembly.

[0135] In this embodiment, the bending region of the wound electrode assembly refers to the area where the electrode sheet in the wound electrode assembly is bent due to winding, which is located at the two edges of the wound electrode assembly.

[0136] With this configuration, the compaction structure 32 does not press down on the curved areas of the wound electrode assembly, thereby reducing the possibility of electrode breakage.

[0137] In some embodiments, the upper hot press 3 is connected to the drive member 1 and configured to move closer to or further away from the lower hot press 2 under the drive of the drive member 1, and only the upper hot press 3 is provided with a compaction structure 32.

[0138] Figure 5 This is a partial structural schematic diagram of a hot pressing device provided in some embodiments of this application.

[0139] Please see Figure 5 In some embodiments, the hot pressing device 200 further includes a pressure sensor 4, a first temperature sensor 5, and a second temperature sensor. The upper hot pressing member 3 is provided with the pressure sensor 4 and the first temperature sensor 5, and the lower hot pressing member 2 is provided with the second temperature sensor. The pressure sensor 4 is used to measure the pressure between the upper hot pressing member 3 and the electrode assembly 600. The first temperature sensor 5 is used to measure the temperature of the upper hot pressing member 3, and the second temperature sensor is used to measure the temperature of the lower hot pressing member 2.

[0140] For example, both the pressure sensor 4 and the first temperature sensor 5 are disposed inside the upper hot press 3.

[0141] For example, the second temperature sensor is disposed inside the lower hot press 2.

[0142] By setting up pressure sensor 4, first temperature sensor 5, and second temperature sensor, pressure and temperature parameters during the hot pressing process can be monitored, enabling precise monitoring of pressure and temperature in the hot pressing process.

[0143] Optionally, the hot pressing device 200 also includes a controller 6. The drive unit 1, pressure sensor 4, first temperature sensor 5 and second temperature sensor are respectively connected to the controller 6. The controller 6 controls the pressure of the hot pressing process and monitors the temperature.

[0144] Optionally, the controller 6 is also connected to a heating mechanism within the plate body to control the temperature of the hot pressing process. For example, the heating structure is the aforementioned resistance wire or resistance rod.

[0145] Secondly, this application also provides a battery production system 100, including a forming device 300 and the hot pressing device 200 described above. The forming device 300 is used to wind or stack positive electrode sheets, negative electrode sheets and separators to form an electrode assembly 600.

[0146] Figure 6 The diagram shows the structure of a single battery cell provided in some embodiments of this application.

[0147] Please see Figure 6 Thirdly, embodiments of this application also provide a battery cell 700, which includes a housing 710 and an electrode assembly 600. The electrode assembly 600 is located inside the housing 710 and is configured to be hot-pressed by the aforementioned hot-pressing device. The surface of the electrode assembly 600 is provided with a recess 620 corresponding to at least a portion of the compaction structure 32. The recess 620 surrounds an area corresponding to a pair of openings 321.

[0148] The outer casing 710 in this embodiment can be a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite casing 710), etc.

[0149] The electrode assembly 600 in this embodiment can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0150] Optionally, the electrode assembly 600 is a wound electrode assembly 600, and the indentation 620 does not interfere with the edge bending area of ​​the wound electrode assembly 600. This reduces the impact of the compaction structure on the electrode sheet in the bending area.

[0151] The indentation 620 on the surface of the electrode assembly 600 in this embodiment can correspond to the entire compaction structure 32 or only to a part of the compaction structure 32.

[0152] Figure 7 This is a schematic diagram of the structure of a battery device provided in some embodiments of this application.

[0153] Please see Figure 7 This application also provides a battery device 800, which includes the battery cell 700 described above.

[0154] The battery device 800 mentioned in the embodiments of this application may include one or more battery cell assemblies 810 for providing voltage and capacity. The battery cell assembly 810 includes a plurality of battery cells 700, which are connected in series, parallel, or mixed connection via a busbar.

[0155] In some embodiments, the battery cell assembly 810 is typically formed by arranging a plurality of battery cells 700; as an example, the battery cell assembly 810 can be a battery module, which is formed by arranging and fixing a plurality of battery cells 700 into a single module. As an example, a battery module can be formed by bundling a plurality of battery cells 700 together with cable ties.

[0156] In some embodiments, the battery device 800 may be a battery pack, which includes a housing 820 and one or more battery cell assemblies 810, the battery cell assemblies 810 being housed in the housing 820.

[0157] As an example, the battery cell assembly 810 can be a battery module, and the battery cell assembly 810 can be housed in the housing 820 by fixing the battery module in the housing 820.

[0158] As an example, the battery cell assembly 810 can also be housed in the housing 820 by directly fixing multiple battery cells 700 to the housing 820.

[0159] As an example, the housing 820 may include a first housing and a second housing. The first housing and the second housing are fastened together to form a closed space inside the housing to house the battery cell assembly 810. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first housing may be a top cover or a bottom plate.

[0160] As an example, the housing 820 may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame, so that the interior of the housing 820 forms an enclosed space to house the battery cell assembly 810.

[0161] As an example, the housing 820 can be part of the chassis structure of the vehicle 900. For example, the top cover of the housing 820 can be at least part of the floor of the vehicle 900, or the frame of the housing 820 can be at least part of the crossbeams and longitudinal beams of the vehicle 900.

[0162] In some embodiments, battery device 800 refers to an energy storage device, which includes a housing 820, and at least one side of the housing 820 has a door. The energy storage device includes energy storage containers, energy storage cabinets, etc.

[0163] Figure 8 This is a structural schematic diagram of a vehicle 900 provided in some embodiments of this application.

[0164] Please see Figure 8 This application embodiment also provides an electrical device, including the battery device 800 described above, which is used to provide electrical energy.

[0165] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery cells 700 and battery devices 800, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft. For ease of explanation, the following embodiments use a vehicle as an example of an electrical device.

[0166] The vehicle 900 has a battery device 800 installed inside it. The battery device 800 can be located at the bottom, front, or rear of the vehicle 900. The battery device 800 can be used to power the vehicle 900; for example, the battery device 800 can serve as the operating power source for the vehicle 900.

[0167] The vehicle 900 may also include a controller 910 and a motor 920. The controller 910 is used to control the battery device 800 to supply power to the motor 920, for example, for the power needs of the vehicle 900 during startup, navigation and driving.

[0168] In some embodiments of this application, the battery device 800 can not only serve as the operating power source for the vehicle 900, but also as the driving power source for the vehicle 900, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 900.

[0169] Please see Figures 2-4This application provides a hot pressing device 200 for hot pressing an electrode assembly 600. The electrode assembly 600 includes a tab 610, which protrudes along a first direction X. The hot pressing device 200 includes a driving member 1, a lower hot pressing member 2, and an upper hot pressing member 3. The upper hot pressing member 3 is disposed opposite to the lower hot pressing member 2, and is connected to the driving member 1 and configured to move closer to or away from the lower hot pressing member 2 under the drive of the driving member 1. At least one of the upper hot press member 3 and the lower hot press member 2 includes a plate body 31 and a compaction structure 32. The compaction structure 32 is located on the side of the plate body 31 facing the electrode assembly 600. The plate body 31 is used to generate heat, and the compaction structure 32 is used to press against the electrode assembly 600. The compaction structure 32 has at least one pair of openings 321 arranged opposite to each other along a first direction X. The two pairs of openings 321 extend toward the central region of the compaction structure 32 in the first direction X. The plate body 31 covers the openings 321 and is used to press against the electrode assembly 600 through the openings 321. At least one pair of openings 321 is located in the central region of the compaction structure 32 in a second direction Y, where the first direction X and the second direction Y intersect. The compaction structure 32 includes at least two first compaction portions 322 and one second compaction portion 323. The two first compaction portions 322 are spaced apart along the second direction Y and connected by the second compaction portion 323. The two first compaction portions 322 and the second compaction portion 323 surround and form a pair of openings 321. The projection of the compaction structure 32 along the third direction Z on the plate body 31 is located within the plate body 31, and the third direction Z is parallel to the arrangement direction of the plate body 31 and the compaction structure 32.

[0170] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0171] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A hot-pressing device for hot-pressing an electrode assembly, the electrode assembly including a tab protruding along a first direction, characterized in that, The application relates to a heat pressing device for an electrode assembly, comprising: a driving member; a lower heat pressing member; an upper heat pressing member, which is arranged opposite to the lower heat pressing member, at least one of the upper heat pressing member and the lower heat pressing member is connected with the driving member and is configured to move towards or away from the other one under the driving of the driving member; wherein at least one of the upper heat pressing member and the lower heat pressing member comprises a plate body and a compacting structure, the compacting structure is located on a side of the plate body facing the electrode assembly, the plate body is used for generating heat, and the compacting structure is used for pressing the electrode assembly, the compacting structure is provided with at least one pair of openings arranged opposite to each other along the first direction, and the two openings of each pair respectively extend to the central region of the compacting structure in the first direction, and the plate body covers at least part of the openings and is used for pressing the electrode assembly through the openings.

2. The hot press apparatus according to claim 1, wherein The compacting structure is provided with multiple pairs of openings, and the multiple pairs of openings are arranged in the second direction, and the first direction and the second direction intersect.

3. The hot press apparatus of claim 1, wherein At least one pair of openings in all the openings is located in the central region of the compacting structure in the second direction, and the first direction and the second direction intersect.

4. The hot press apparatus of claim 1, wherein The compacting structure comprises at least two first compacting parts and one second compacting part, the two first compacting parts are arranged in the second direction and are connected through the second compacting part, and the two first compacting parts and the second compacting part surround to form a pair of openings, and the first direction and the second direction intersect.

5. The hot press apparatus according to claim 4, wherein The number of the first compacting parts is greater than two, the number of the second compacting parts is at least two, the multiple first compacting parts and the multiple second compacting parts are arranged in the second direction in sequence and in a spaced manner, respectively, any two adjacent first compacting parts are connected through the second compacting part, and the multiple first compacting parts and the multiple second compacting parts surround to form multiple pairs of openings arranged in the second direction in a spaced manner.

6. The hot press apparatus of claim 4, wherein The number of the first compacting parts is two, the number of the second compacting parts is one, the size of the first compacting part in the second direction is W1, the size of the second compacting part in the second direction is W2, and the W1 and the W2 satisfy: W1<=W2.

7. The hot press apparatus of claim 6, wherein The W1, the W2 and the W3 satisfy: 1 / 4W3<=W1<=W2<=1 / 2W3.

8. The hot press apparatus of claim 4, wherein The two openings of each pair are arranged in a mirror image, and / or the two first compacting parts are arranged in a mirror image.

9. The hot press apparatus of claim 1, wherein The size of the opening in the first direction is h1, the size of the compacting structure in the first direction is h2, and the h1 and the h2 satisfy: 35%<=h1 / h2<=45%.

10. The hot press apparatus of claim 9, wherein The h1 and the h2 satisfy: 38%<=h1 / h2<=42%.

11. The hot press apparatus of claim 1, wherein The plate body and the compacting structure are integrally formed.

12. The hot press apparatus of claim 1, wherein, The compacting structure is pasted on the plate body.

13. The hot press apparatus of claim 1, wherein The projection of the compacting structure on the plate body in the third direction is located in the plate body, and the third direction is parallel to the arrangement direction of the plate body to the compacting structure.

14. The hot press apparatus of claim 1, wherein, The hot-pressing device further comprises a pressure sensor, a first temperature sensor and a second temperature sensor, the upper hot-pressing part is provided with the pressure sensor and the first temperature sensor, the lower hot-pressing part is provided with the second temperature sensor, the pressure sensor is used for measuring the pressure between the upper hot-pressing part and the electrode assembly, the first temperature sensor is used for measuring the temperature of the upper hot-pressing part, and the second temperature sensor is used for measuring the temperature of the lower hot-pressing part.

15. A battery production system characterized by comprising: Comprising: a forming device for winding or laminating a positive electrode tab, a negative electrode tab and a separator film to form an electrode assembly; The hot-pressing device according to any one of claims 1-14.

16. A battery cell, characterized by Comprising: a housing; an electrode assembly located in the housing, the electrode assembly being configured to be hot-pressed by the hot-pressing device according to any one of claims 1-14, a surface of the electrode assembly being provided with indentations corresponding to at least part of the compacting structure, the indentations surrounding to form an area corresponding to the pair of openings.

17. A battery device characterized by comprising: A battery cell comprising the battery cell according to claim 16.

18. An electrical device, comprising: A battery device comprising the battery device according to claim 17, the battery device being configured to provide electrical energy. A battery cell comprising the battery cell according to claim 16. A battery device comprising the battery device according to claim 17, the battery device being configured to provide electrical energy.

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