Isostatic pressing clamp assembly, isostatic pressing system and isostatic pressing method for electrode assembly

Abstract

Disclosed in the present application are an isostatic pressing clamp assembly, an isostatic pressing system and an isostatic pressing method for an electrode assembly. The isostatic pressing clamp assembly comprises two clamps and a limiting member. The two clamps are used for clamping an electrode body of an electrode assembly from two sides in the thickness direction of the electrode assembly during isostatic pressing of the electrode assembly, so as to improve the stability and reliability of the electrode assembly during isostatic pressing treatment. The limiting member is used to be arranged on at least one side of a tab of the electrode assembly in the thickness direction during isostatic pressing of the electrode assembly, so as to limit the tab in the thickness direction, thereby reducing the risks of bulging, deformation, etc. of the tab in the thickness direction during isostatic pressing, helping to improve the flatness of the electrode assembly, reducing the risk of stress concentration, etc. of the electrode assembly in subsequent processes, and improving the performance of the electrode assembly and battery cells.

Description

Isostatic pressing method for isostatic pressing fixture assembly, isostatic pressing system and electrode assembly Cross-reference to related applications

[0001] This application claims priority to Chinese patent application 202510188952.9, filed on February 20, 2025, entitled “Isostatic pressing fixture assembly, isostatic pressing system and isostatic pressing method for electrode assembly”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery manufacturing technology, and in particular to an isostatic pressing fixture assembly, an isostatic pressing system, and an isostatic pressing method for electrode assemblies. Background Technology

[0003] In recent years, power batteries have made great strides and can be widely used in energy storage power systems such as hydropower, thermal power, wind power and solar power plants, as well as in electric vehicles, power tools, military equipment and aerospace.

[0004] In the development of battery technology, the performance of individual battery cells directly affects the overall performance of the power battery. In current battery cells, the tabs of the electrode assembly are prone to bulging and deformation during isostatic pressing, affecting the flatness of the electrode assembly. This can lead to stress concentration in subsequent processes, severely impacting the performance of the battery cell. Summary of the Invention

[0005] This application provides an isostatic pressing fixture assembly, an isostatic pressing system, and an isostatic pressing method for electrode assemblies, which can improve the performance of electrode assemblies and battery cells.

[0006] In a first aspect, embodiments of this application provide an isostatic pressing fixture assembly, including two clamps and a limiting member. The two clamps are used to clamp the electrode body of the electrode assembly from both sides of the electrode assembly in the thickness direction during the isostatic pressing process of the electrode assembly; the limiting member is used to be disposed on at least one side of the electrode tab of the electrode assembly in the thickness direction during the isostatic pressing process of the electrode assembly.

[0007] In the above solution, by using two clamps to hold the electrode body of the electrode assembly from both sides along the thickness direction during the isostatic pressing process, the stability and reliability of the electrode assembly during isostatic pressing can be improved. Simultaneously, during isostatic pressing, a limiting member is pressed against at least one side of the electrode tab along the thickness direction of the electrode assembly to limit the tab in that direction. This reduces the risk of the tab bulging or deforming along the thickness direction during isostatic pressing, helps improve the flatness of the electrode assembly, reduces the risk of stress concentration and short circuits in subsequent processes, and improves the performance of both the electrode assembly and the individual battery cells.

[0008] In some embodiments, at least a portion of the limiting member comprises an elastic material.

[0009] In the above solution, at least part of the limiting component includes an elastic material, which can reduce the risk of stress concentration when the limiting component presses against the tab, thereby reducing the possibility of scratches, indentations or deformation of the tab and improving the performance of the tab.

[0010] In some embodiments, the limiting member includes two first clamping portions, which are used to press against both sides of the electrode tab along the thickness direction during isostatic pressing.

[0011] In the above scheme, by pressing the two first clamping parts against both sides of the tab along the thickness direction during the isostatic pressing process, the tab after isostatic pressing can be approximately located at the center position of the electrode body along the thickness direction, which helps to reduce the difficulty of connecting the tab and the adapter, and realize the electrical connection between the tab and the electrode terminal through the adapter.

[0012] In some embodiments, two first clamping portions are respectively disposed on two clamps, at least a portion of the first clamping portion protruding from the side of the clamp facing the electrode assembly and used to press against the electrode tab.

[0013] In the above solution, two first clamping parts are respectively disposed on two clamps. The connection between the two clamps enables clamping of the electrode tab in the thickness direction without the need for additional connecting structures. This saves production costs and reduces the assembly difficulty between the limiting component and the electrode tab. Furthermore, at least a portion of the first clamping part protrudes from the side of the clamp facing the electrode assembly. When the electrode body is clamped from both sides by the two clamps, the protruding portion of the first clamping part relative to the corresponding clamp can be used to press against the electrode tab, thereby limiting the electrode tab and reducing the risk of bulging deformation during isostatic pressing.

[0014] In some embodiments, the clamp includes a second clamping portion, at least a portion of which comprises an elastic material, and the second clamping portion is used to press against the electrode body.

[0015] In the above solution, the clamp includes a second clamping part, and at least part of the second clamping part includes an elastic material, so that the second clamping part has a certain elastic buffering capacity. By pressing the electrode body against the electrode body during the isostatic pressing process of the electrode assembly, the risk of stress concentration in the electrode body can be reduced, the possibility of scratches, indentations or deformation in the electrode body can be reduced, and the performance of the electrode body can be improved.

[0016] In some embodiments, the Shore hardness of the second clamping portion is greater than the Shore hardness of the first clamping portion.

[0017] In the above scheme, the Shore hardness of the second clamping part is greater than that of the first clamping part. In other words, the first clamping part has a stronger stress buffering capacity than the second clamping part, thereby reducing the risk of damage to the electrode tab caused by the first clamping part during isostatic pressing.

[0018] In some embodiments, the elastic modulus of the second clamping portion is greater than that of the first clamping portion.

[0019] In the above scheme, the elastic modulus of the second clamping part is greater than that of the first clamping part, so that the first clamping part has better elastic deformation ability than the second clamping part, thereby reducing the risk of the first clamping part damaging the tab during the isostatic pressing process.

[0020] In some embodiments, the clamp further includes a support portion, at least one of a first clamping portion and a second clamping portion being disposed on the support portion and located on the side of the support portion facing the electrode assembly.

[0021] In the above solution, by providing a support portion in the fixture, at least one of the first clamping portion and the second clamping portion is disposed on the support portion and located on the side of the support portion facing the electrode assembly. During the isostatic pressing process of the electrode assembly, the support portion can support at least one of the first clamping portion and the second clamping portion, thereby improving the stability and reliability of the first clamping portion and the second clamping portion when pressing against the corresponding component of the electrode assembly.

[0022] In some embodiments, at least one of the first clamping portion and the second clamping portion is bonded to the support portion.

[0023] In the above solution, at least one of the first clamping part and the second clamping part is bonded to the support part, which can improve the stability of at least one of the first clamping part and the second clamping part, reduce the difficulty of connecting it to the support part, and improve assembly efficiency.

[0024] In some embodiments, the first clamping portion and the second clamping portion are arranged along a first direction, which is perpendicular to the thickness direction; or, the first clamping portion is disposed on the side of the second clamping portion facing the electrode assembly along a second direction, which is parallel to the thickness direction.

[0025] In the above scheme, the first clamping part and the second clamping part are arranged along a first direction, which is perpendicular to the thickness direction. This reduces the mutual interference and influence between the first clamping part and the second clamping part. When the first clamping part and the second clamping part press against the electrode tab and the electrode body respectively during the isostatic pressing process of the electrode assembly, it helps to improve the stability of the electrode tab and the electrode body. Alternatively, the first clamping part can be located on the side of the second clamping part facing the electrode assembly. When the first clamping part presses against the electrode tab, the second clamping part can generate a certain elastic buffering effect, thereby reducing the risk of stress concentration between the first clamping part and the electrode tab.

[0026] In some embodiments, the first clamping portion includes a protruding sub-portion that protrudes from the side of the corresponding clamp facing the electrode assembly. The thickness D of the protruding sub-portion satisfies: (hN*d) / 4≤D≤(hN*d) / 2, where h is the thickness of the electrode body after isostatic pressing, N is the number of current collector layers in the electrode assembly, and d is the thickness of a single current collector layer in the electrode assembly.

[0027] In the above solution, by reasonably setting the thickness of the protruding part of the first clamping part, the pressing effect of the first clamping part on the tab during the isostatic pressing process of the electrode assembly can be improved, so that the first clamping part can provide sufficient support for the tab during the isostatic pressing process of the electrode assembly, thereby further reducing the risk of the tab bulging and deforming during the isostatic pressing process.

[0028] Secondly, embodiments of this application provide an isostatic pressing system, including an isostatic pressing device and an isostatic pressing fixture assembly as described above. The isostatic pressing device is provided with a static pressure chamber, and the isostatic pressing fixture assembly is disposed within the static pressure chamber.

[0029] Thirdly, embodiments of this application provide an isostatic pressing method for an electrode assembly, the isostatic pressing method comprising:

[0030] The two clamps of the isostatic pressing fixture assembly are clamped on both sides of the electrode body of the electrode assembly along the thickness direction of the electrode assembly, and the limiting member of the isostatic pressing fixture assembly is pressed against at least one side of the electrode tab of the electrode assembly along the thickness direction.

[0031] The electrode assembly and isostatic clamp assembly are placed in the static pressure chamber of the isostatic pressing device for isostatic pressing treatment.

[0032] In the above solution, the electrode body is held from both sides by two clamps, and the limiting member presses against at least one side of the tab along the thickness direction. Then, the electrode assembly and the isostatic pressing fixture assembly are placed in the static pressing chamber for isostatic pressing. This reduces the assembly difficulty of the electrode assembly and the isostatic pressing fixture assembly. Furthermore, during the isostatic pressing process, the clamping action of the two clamps on the electrode body can improve the stability and reliability of the electrode body during the isostatic pressing process. The limiting action of the limiting member on the tab can reduce the risk of bulging deformation of the tab along the thickness direction, which helps to improve the flatness of the electrode assembly, reduce the risk of stress concentration in subsequent processes, and improve the performance of the electrode assembly and the battery cell.

[0033] In some embodiments, during the step of pressing the limiting member of the isostatic pressing fixture assembly against at least one side of the electrode lug of the electrode assembly along the thickness direction,

[0034] The limiting components are arranged at intervals with the electrode body.

[0035] In the above solution, by setting a limiting member that is spaced apart from the electrode body when pressing the tab, the risk of the limiting member affecting the electrode active material inside the electrode body can be reduced, thereby improving the performance of the electrode body.

[0036] In some embodiments, during the step of pressing the limiting member of the isostatic pressing fixture assembly against at least one side of the electrode lug of the electrode assembly along the thickness direction,

[0037] The distance H between the limiting component and the electrode body satisfies: 2 mm ≤ H ≤ 10 mm.

[0038] In the above scheme, the distance between the limiting component and the electrode body is greater than or equal to 2 mm and less than or equal to 10 mm. On the one hand, this can reduce the risk of the limiting component affecting the active material at the root of the electrode tab. On the other hand, it can also improve the limiting effect of the limiting component on the electrode tab and reduce the risk of the electrode tab bulging and deforming during the isostatic pressing process.

[0039] In some embodiments, before the steps of clamping the two clamps of the isostatic pressing fixture assembly on both sides of the electrode body of the electrode assembly along the thickness direction of the electrode assembly, and pressing the limiting member of the isostatic pressing fixture assembly against at least one side of the electrode tab of the electrode assembly along the thickness direction, the method further includes the step of:

[0040] The electrode assembly is wrapped from the outside by a protective component.

[0041] In the above scheme, the electrode assembly is first wrapped from the outside by a protective component, and then the electrode assembly wrapped with the protective component is fixed by an isostatic clamping assembly. During the isostatic pressing process of the electrode assembly, the protective component can protect the electrode assembly and isolate the electrode assembly and the isostatic medium filling the static pressure cavity, thereby reducing the risk of the isostatic medium affecting the performance of the electrode assembly.

[0042] In some embodiments, the protective component includes a first protective film and a second protective film, and the step of covering the electrode assembly from the outside with the protective component includes:

[0043] The first protective film and the second protective film are disposed on both sides of the electrode assembly along the thickness direction;

[0044] The first and second protective films are circumferentially sealed together to cover the electrode assembly.

[0045] In the above solution, the first and second protective films are disposed on both sides of the electrode assembly along the thickness direction, and then sealed together along the circumference of the first and second protective films, thereby achieving the covering of the electrode assembly and reducing the difficulty of covering the electrode assembly with protective components. Furthermore, disposing of the first and second protective films on both sides of the electrode assembly along the thickness direction ensures that the connection point between the first and second protective films is located outside the contact area between the electrode assembly and the isostatic pressing fixture assembly, thus reducing the risk of indentation or other damage to the electrode assembly under the action of the isostatic pressing fixture assembly.

[0046] In some embodiments, both the side of the first protective film facing the electrode assembly and the side of the second protective film facing the electrode assembly are provided with receiving grooves.

[0047] In the step of setting the first protective film and the second protective film on both sides of the electrode assembly along the thickness direction,

[0048] One part of the electrode body of the electrode assembly is located in the receiving groove of the first protective film, and the other part is located in the receiving groove of the second protective film.

[0049] In the above solution, the first protective film and the second protective film are provided with receiving grooves, so that a part of the electrode body is located in the receiving groove of the first protective film and another part is located in the receiving groove of the second protective film, which can reduce the risk of damage to the electrode body caused by the first protective film and the second protective film.

[0050] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0051] The features, advantages, and technical effects of exemplary embodiments of this application will now be described with reference to the accompanying drawings.

[0052] Figure 1 is an exploded view of a battery cell according to some embodiments of this application;

[0053] Figure 2 is a schematic diagram of the structure of an electrode assembly according to some embodiments of this application;

[0054] Figure 3 is a structural schematic diagram of an isostatic pressure fixture assembly provided in some embodiments of this application;

[0055] Figure 4 is another structural schematic diagram of the isostatic pressure fixture assembly provided in some embodiments of this application;

[0056] Figure 5 is a structural schematic diagram of an isostatic pressure fixture assembly provided in some other embodiments of this application;

[0057] Figure 6 is a side view of an isostatic pressure fixture assembly provided in some embodiments of this application;

[0058] Figure 7 is a flowchart of an isostatic pressing method for an electrode assembly provided in some embodiments of this application;

[0059] Figure 8 is a side view of the isostatic pressure fixture assembly and electrode assembly provided in some embodiments of this application after assembly;

[0060] Figure 9 is another flowchart of the isostatic pressing method for electrode assemblies provided in some embodiments of this application;

[0061] Figure 10 is an exploded view of the isostatic clamping fixture assembly and electrode assembly provided in some embodiments of this application;

[0062] Figure 11 is another flowchart of the isostatic pressing method for electrode assemblies provided in some embodiments of this application.

[0063] The attached icons are numbered as follows:

[0064] Battery cell 10; end cap 11; housing 12; electrode assembly 13; electrode body 131; tab 132; clamp 20; second clamping part 21; support part 22; limiting member 30; first clamping part 31; protruding sub-part 311; connecting sub-part 312; protective assembly 40; first protective film 41; second protective film 42; receiving groove K1; first direction X; second direction Y. Detailed Implementation

[0065] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.

[0066] In the description of this application, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationships, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Vertical" is not vertical in the strict sense, but within the allowable tolerance range. "Parallel" is not parallel in the strict sense, but within the allowable tolerance range.

[0067] In this application, the reference to "embodiment" means that a specific 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 throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0068] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of this application. It should also be noted in the description of this application that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0069] 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. Battery cells are generally classified into three types according to their packaging method: cylindrical battery cells, cuboid / square battery cells, and pouch battery cells, and the embodiments of this application are not limited thereto.

[0070] The battery mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in this application may include a battery module or a battery pack. A battery generally includes a housing for encapsulating one or more battery cells. The housing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0071] For example, the battery cell can be a solid-state battery cell.

[0072] In the development of battery technology, the performance of individual battery cells directly affects the overall performance of the power battery. To improve the performance of solid-state battery cells, isostatic pressing is usually required for the electrode components inside the solid-state battery cell to achieve high density. However, in current electrode components, the electrode body is prone to significant shrinkage during isostatic pressing, causing the tabs to bulge and deform, which seriously affects the overall flatness of the electrode component. This may lead to stress concentration, short circuits, and other issues in subsequent processes (such as battery cycle performance testing), affecting the performance of the battery cell.

[0073] To address at least some of the aforementioned technical problems, embodiments of this application provide an isostatic pressing fixture assembly, including two clamps and a limiting member. The two clamps hold the electrode body of the electrode assembly from both sides along its thickness direction during the isostatic pressing process, thereby improving the stability and reliability of the electrode assembly during isostatic pressing. Simultaneously, during isostatic pressing, the limiting member presses against at least one side of the electrode tab along its thickness direction to limit the tab's position. This reduces the risk of the tab bulging or deforming along the thickness direction during isostatic pressing, helps improve the flatness of the electrode assembly, reduces the risk of stress concentration and short circuits in subsequent processes, and ultimately improves the performance of both the electrode assembly and the individual battery cells.

[0074] The battery cells disclosed in this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power system for such an electrical device can be constructed using battery cells and batteries disclosed in this application, which helps improve the stability of battery performance and battery life.

[0075] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0076] Please refer to Figures 1 and 2. Figure 1 is an exploded structural diagram of a battery cell 10 provided in some embodiments of this application, and Figure 2 is a structural diagram of an electrode assembly 13 provided in some embodiments of this application. A battery cell 10 refers to the smallest unit that makes up a battery. As shown in Figure 1, the battery cell 10 includes an end cap 11, a housing 12, an electrode assembly 13, and other functional components. The electrode assembly 13 is the component in the battery cell 10 where electrochemical reactions occur. The housing 12 may contain one or more electrode assemblies 13.

[0077] For example, the battery cell 10 is a solid-state battery cell 10. In the solid-state battery cell 10, the electrode assembly 13 includes a positive electrode and a negative electrode stacked together. The electrode is provided with a solid electrolyte.

[0078] In some alternative embodiments, the solid electrolyte includes one or more of sulfide solid electrolytes, oxide solid electrolytes, halide solid electrolytes, and polymer solid electrolytes. Sulfide solid electrolytes include crystalline sulfide solid electrolytes, sulfide glasses, and glass-ceramic solid electrolytes.

[0079] Please refer to Figures 2 and 3. In a first aspect, embodiments of this application provide an isostatic pressing fixture assembly, including two clamps 20 and a limiting member 30. The two clamps 20 are used to clamp the electrode body 131 of the electrode assembly 13 from both sides of the electrode assembly 13 in the thickness direction during the isostatic pressing process. The limiting member 30 is used to be disposed on at least one side of the tab 132 of the electrode assembly 13 in the thickness direction during the isostatic pressing process.

[0080] Specifically, the clamps 20 are components used to press against the electrode body 131 of the electrode assembly 13 during the isostatic pressing process, thereby limiting the position of the electrode body 131. During the isostatic pressing process of the electrode assembly 13, two clamps 20 are arranged on both sides of the electrode body 131 along the thickness direction. The two clamps 20 can be connected to each other, thereby clamping the electrode body 131 from both sides of the electrode body 131 through the two clamps 20. Optionally, the two clamps 20 can be detachably connected to reduce assembly difficulty. During the isostatic pressing process, the two clamps 20 can be directly connected or indirectly connected by means of bolts or other structures. For example, both clamps 20 can each have through holes extending along the thickness direction, and bolts can pass through the through holes of the two clamps 20 and engage with nuts, thereby locking the two clamps 20. The clamps 20 can directly clamp the electrode body 131 or indirectly clamp the electrode body 131 through structures such as protective films. The two clamps 20 can be the same clamp 20 or different clamps 20. The structure of the clamp 20 can be various; for example, the clamp 20 can be a one-piece molded structure, or it can be a composite structure composed of multiple parts. The material of the clamp 20 can be various; for example, the material of the clamp 20 can include elastic materials, rigid materials, or it can be a composite structure composed of both elastic and rigid materials.

[0081] The limiting member 30 is a component used to press against the tab 132 of the electrode assembly 13 along the thickness direction during the isostatic pressing process of the electrode assembly 13, thereby limiting the tab 132. The limiting member 30 can press against the tab 132 from one side along the thickness direction to limit the tab 132 on that side. Optionally, when the limiting member 30 presses against the tab 132 from one side along the thickness direction, the other side of the tab 132 can be pressed by a clamp 20 to limit the tab 132 on the side of the tab 132 away from the limiting member 30. Alternatively, the limiting member 30 can include two parts that can press against the tab 132 from both sides along the thickness direction to limit the tab 132 on both sides. The limiting member 30 can directly press against the tab 132 or indirectly press against the tab 132 through a structure such as a protective film. The limiting member 30 can be made of various materials. For example, the limiting member 30 can be made of elastic materials such as silicone, or it can be made of rigid materials.

[0082] In the above scheme, by using two clamps 20 to hold the electrode body 131 of the electrode assembly 13 from both sides during the isostatic pressing process, the stability and reliability of the electrode assembly 13 during the isostatic pressing process can be improved. At the same time, during the isostatic pressing process, the limiting member 30 is pressed against at least one side of the tab 132 of the electrode assembly 13 along the thickness direction to limit the tab 132 in that thickness direction. This can reduce the risk of the tab 132 bulging and deforming along the thickness direction during the isostatic pressing process, which helps to improve the flatness of the electrode assembly 13, reduce the risk of stress concentration and short circuit in subsequent processes, and improve the performance of the electrode assembly 13 and the battery cell 10.

[0083] In some embodiments, at least a portion of the limiting member 30 comprises an elastic material.

[0084] The limiting member 30 can be made entirely of an elastic material, or the portion of the limiting member 30 that contacts the tab 132 can be made of an elastic material, while the other portion can be made of a rigid material. The material of the limiting member 30 can include various materials capable of elastic deformation, such as silicone.

[0085] In the above solution, at least a portion of the limiting member 30 includes an elastic material, which can reduce the risk of stress concentration when the limiting member 30 presses against the tab 132, thereby reducing the possibility of scratches, indentations or deformation of the tab 132 and improving the performance of the tab 132.

[0086] Please refer to Figure 3. In some embodiments, the limiting member 30 includes two first clamping parts 31, which are used to press against both sides of the tab 132 along the thickness direction during isostatic pressing.

[0087] During the isostatic pressing process of the electrode assembly 13, the two first clamping parts 31 can press against both sides of the electrode tab 132 along the thickness direction to clamp the electrode tab 132 from both sides and limit its position. During the isostatic pressing process, the two first clamping parts 31 are connected to each other in various ways. For example, the two first clamping parts 31 can be directly connected as a single integral structure. Alternatively, the two first clamping parts 31 can be two separate components, which can be indirectly connected by bolts, nuts, or other structures. Alternatively, the two first clamping parts 31 can be respectively mounted on two clamps 20, and connected by the two clamps 20. The two first clamping parts 31 can be correspondingly mounted on the two clamps 20, or they can be separately mounted from the two clamps 20. It can be seen that when the two first clamping parts 31 are separated from the two clamps 20, the two first clamping parts 31 are located outside the corresponding areas of the two clamps 20. When the two clamps 20 clamp the electrode bodies 131, the electrode tabs 132 can be in a suspended state. At this time, the electrode tabs 132 can be clamped by the two first clamping parts 31 to constrain the electrode tabs 132 during the isostatic pressing process.

[0088] In the above scheme, the two first clamping parts 31 press against the two sides of the tab 132 along the thickness direction during the isostatic pressing process, so that the tab 132 after isostatic pressing is approximately located at the center position of the electrode body 131 along the thickness direction, which helps to reduce the difficulty of connecting the tab 132 and the adapter, and realizes the electrical connection between the tab 132 and the electrode terminal through the adapter.

[0089] Referring to Figure 4, in some embodiments, two first clamping portions 31 are respectively disposed on two clamps 20. At least a portion of the first clamping portion 31 protrudes from the side of the clamp 20 facing the electrode assembly 13 and is used to press against the tab 132.

[0090] Two first clamping portions 31 are correspondingly provided with two clamps 20. The first clamping portion 31 can be fixedly connected to the corresponding clamp 20 in various ways; for example, the first clamping portion 31 can be bonded to the clamp 20. Alternatively, the first clamping portion 31 can be movably disposed relative to the corresponding clamp 20. When it is not necessary to press the tab 132, the first clamping portion 31 can be separated from the clamp 20; when it is necessary to press the tab 132, the first clamping portion 31 is located between the corresponding clamp 20 and the tab 132. It is known that, in the thickness direction, the thickness of the electrode body 131 is usually greater than the thickness of the tab 132. Therefore, at least one side of the tab 132 in the thickness direction is usually recessed relative to the corresponding side of the electrode body 131.

[0091] In the above solution, two first clamping parts 31 are respectively disposed on two clamps 20. The connection of the two clamps 20 enables the clamping of the electrode tab 132 in the thickness direction without the need for additional connecting structures to connect the two first clamping parts 31. This helps to save production costs and reduces the assembly difficulty of the limiting member 30 and the electrode tab 132. On this basis, at least a portion of the first clamping part 31 protrudes from the side of the clamp 20 facing the electrode assembly 13. When the electrode body 131 is clamped from both sides by the two clamps 20, the protruding portion of the first clamping part 31 relative to the corresponding clamp 20 can be used to press against the electrode tab 132, thereby limiting the electrode tab 132 and reducing the risk of the electrode tab 132 bulging and deforming during isostatic pressing.

[0092] Please continue to refer to Figure 4. In some embodiments, the clamp 20 includes a second clamping portion 21, at least a portion of which comprises an elastic material. The second clamping portion 21 is used to press against the electrode body 131.

[0093] Both clamps 20 include a second clamping portion 21, which can clamp the electrode body 131 from both sides during the isostatic pressing process of the electrode assembly 13. The second clamping portion 21 can be made entirely of an elastic material, or a portion of the second clamping portion 21 can be made of an elastic material while the other portion is made of a rigid material. The material of the second clamping portion 21 can include various materials capable of elastic deformation, such as silicone.

[0094] In the above solution, the clamp 20 includes a second clamping part 21, and at least a portion of the second clamping part 21 includes an elastic material, thereby giving the second clamping part 21 a certain elastic buffering capacity. By having the second clamping part 21 press against the electrode body 131 during the isostatic pressing process of the electrode assembly 13, the risk of stress concentration in the electrode body 131 can be reduced, the possibility of scratches, indentations or deformation in the electrode body 131 can be reduced, and the performance of the electrode body 131 can be improved.

[0095] In some embodiments, the Shore hardness of the second clamping portion 21 is greater than the Shore hardness of the first clamping portion 31.

[0096] Optionally, the Shore hardness of the first clamping part 31 can be greater than or equal to 20 degrees and less than 40 degrees. For example, the Shore hardness of the first clamping part 31 can be 20 degrees, 25 degrees, 30 degrees, 35 degrees, 39 degrees, etc. By reasonably setting the Shore hardness of the first clamping part 31, the influence of the first clamping part 31 on the electrode tab 132 when pressing against it can be reduced, thereby reducing the risk of scratches, indentations or deformation of the electrode tab 132.

[0097] Optionally, the Shore hardness of the second clamping part 21 can be greater than or equal to 40 degrees and less than or equal to 70 degrees. For example, the Shore hardness of the second clamping part 21 can be 40 degrees, 45 degrees, 50 degrees, 55 degrees, 70 degrees, etc. By reasonably setting the Shore hardness of the second clamping part 21, the influence of the second clamping part 21 on the electrode body 131 when pressing against it can be reduced, thereby reducing the risk of scratches, indentations or deformation of the electrode body 131.

[0098] In the above scheme, the Shore hardness of the second clamping part 21 is greater than that of the first clamping part 31. In other words, the first clamping part 31 has a stronger stress buffering capacity than the second clamping part 21, thereby reducing the risk of the first clamping part 31 damaging the tab 132 during the isostatic pressing process.

[0099] In some embodiments, the elastic modulus of the second clamping portion 21 is greater than that of the first clamping portion 31.

[0100] Optionally, the elastic modulus of the first clamping part 31 can be greater than or equal to 0.0078 GPa and less than 1 GPa. For example, the elastic modulus of the first clamping part 31 can be 0.0078 GPa, 0.1 GPa, 0.5 GPa, 0.8 GPa, 0.99 GPa, etc. By reasonably setting the elastic modulus of the first clamping part 31, the influence of the first clamping part 31 on the electrode tab 132 when pressing against it can be reduced, thereby reducing the risk of scratches, indentations or deformation of the electrode tab 132.

[0101] Optionally, the elastic modulus of the second clamping part 21 can be greater than or equal to 1 GPa and less than or equal to 10 GPa. For example, the elastic modulus of the second clamping part 21 can be 1 GPa, 2 GPa, 5 GPa, 7 GPa, 10 GPa, etc. By reasonably setting the elastic modulus of the second clamping part 21, the influence of the second clamping part 21 on the electrode body 131 when pressing against it can be reduced, thereby reducing the risk of scratches, indentations or deformation of the electrode body 131.

[0102] In the above scheme, the elastic modulus of the second clamping part 21 is set to be greater than that of the first clamping part 31, so that the first clamping part 31 has better elastic deformation capability than the second clamping part 21, thereby reducing the risk of the first clamping part 31 damaging the tab 132 during the isostatic pressing process.

[0103] Please continue to refer to Figure 4. In some embodiments, the clamp 20 further includes a support portion 22, and at least one of the first clamping portion 31 and the second clamping portion 21 is disposed on the support portion 22 and located on the side of the support portion 22 facing the electrode assembly 13.

[0104] The support portion 22 is a component used to support the first clamping portion 31 and / or the second clamping portion 21 to improve the clamping effect of the first clamping portion 31 and / or the second clamping portion 21 on the corresponding component in the electrode assembly 13. At least one of the first clamping portion 31 and the second clamping portion 21 is disposed on the support portion 22 and located on the side of the support portion 22 facing the electrode assembly 13, such that the first clamping portion 31 and / or the second clamping portion 21 can press against the corresponding component of the electrode assembly 13 under the support of the support portion 22. "At least one of the first clamping portion 31 and the second clamping portion 21 is disposed on the support portion 22" can mean that either the first clamping portion 31 or the second clamping portion 21 is disposed on the support portion 22, or it can mean that both the first clamping portion 31 and the second clamping portion 21 are disposed on the support portion 22.

[0105] It should be noted that when at least one of the first clamping part 31 and the second clamping part 21 is disposed on the support part 22, the first clamping part 31 and the second clamping part 21 can be fixedly connected to the support part 22, or they can be movably disposed relative to the support part 22. There are various ways to fix the first clamping part 31 and the second clamping part 21 to the support part 22; for example, they can be bonded to the support part 22 using an adhesive. The material of the support part 22 can be various; for example, the material of the support part 22 can include metal.

[0106] The support portions 22 of the two clamps 20 can be connected to each other. For example, the support portions 22 of the two clamps 20 can be connected by the cooperation of bolts and nuts. In this case, the support portions 22 of the two clamps 20 can have through holes for bolts to pass through. Furthermore, when the first clamping portion 31 and the second clamping portion 21 are provided on the support portion 22, at least one of the first clamping portion 31 and the second clamping portion 21 can also have through holes for the aforementioned bolts to pass through. When the bolt passes through the through holes of the first clamping portion 31 and / or the second clamping portion 21, the bolt can position the first clamping portion 31 and / or the second clamping portion 21 to a certain extent.

[0107] In the above solution, by providing a support portion 22 in the clamp 20, at least one of the first clamping portion 31 and the second clamping portion 21 is disposed on the support portion 22 and located on the side of the support portion 22 facing the electrode assembly 13. During the isostatic pressing process of the electrode assembly 13, the support portion 22 can support at least one of the first clamping portion 31 and the second clamping portion 21, thereby improving the stability and reliability of the first clamping portion 31 and the second clamping portion 21 when pressing against the corresponding component of the electrode assembly 13.

[0108] In some embodiments, at least one of the first clamping portion 31 and the second clamping portion 21 is bonded to the support portion 22.

[0109] Specifically, the bonding connection between at least one of the first clamping part 31 and the second clamping part 21 and the support part 22 can mean that the first clamping part 31 is bonded to the support part 22, while the second clamping part 21 is not connected to the support part 22 or is connected to the support part 22 in another way; it can also mean that the second clamping part 21 is bonded to the support part 22, while the first clamping part 31 is not connected to the support part 22 or is connected to the support part 22 in another way; or it can mean that both the first clamping part 31 and the second clamping part 21 are bonded to the support part 22. Optionally, the adhesive force between at least one of the first clamping part 31 and the second clamping part 21 and the support part 22 can be 200 N / m to 400 N / m to improve the bonding reliability between at least one of the first clamping part 31 and the second clamping part 21 and the support part 22.

[0110] In the above solution, at least one of the first clamping part 31 and the second clamping part 21 is bonded to the support part 22, which can improve the stability of at least one of the first clamping part 31 and the second clamping part 21, reduce the difficulty of connecting it to the support part 22, and improve assembly efficiency.

[0111] In some embodiments, as shown in FIG4, the first clamping part 31 and the second clamping part 21 are arranged along a first direction X, which is perpendicular to the thickness direction; or, as shown in FIG5, the first clamping part 31 is disposed on the side of the second clamping part 21 facing the electrode assembly 13 along a second direction Y, which is parallel to the thickness direction.

[0112] The first direction X can be the length direction of the electrode assembly 13. In the electrode assembly 13, the electrode body 131 and the tab 132 are arranged along the first direction X. The first clamping part 31 and the second clamping part 21 are arranged along the first direction X. In the second direction Y, the first clamping part 31 can correspond to the position of the tab 132, and the second clamping part 21 can correspond to the position of the electrode body 131. A portion of the first clamping part 31 protrudes from the side of the second clamping part 21 facing the electrode assembly 13. The first clamping part 31 and the second clamping part 21 can respectively press against the tab 132 and the electrode body 131 during the isostatic pressing process of the electrode assembly 13. The first clamping part 31 and the second clamping part 21 can be arranged at intervals along the first direction X, and they are separated from each other. Alternatively, the first clamping part 31 and the second clamping part 21 can also be in contact with each other. Furthermore, the first clamping part 31 and the second clamping part 21 can be connected by means of bonding or the like. When the clamp 20 includes a support portion 22, both the first clamping portion 31 and the second clamping portion 21 can be directly disposed on the side of the support portion 22 facing the electrode assembly 13.

[0113] Alternatively, the first clamping part 31 is disposed on the side of the second clamping part 21 facing the electrode assembly 13 along the second direction Y. In this case, the first clamping part 31 protrudes entirely from the side of the second clamping part 21 facing the electrode assembly 13 to press against the tab 132 during isostatic pressing. Furthermore, a portion of the surface of the second clamping part 21 facing the electrode assembly 13 may be exposed relative to the first clamping part 31 to press against the electrode body 131 during isostatic pressing. The first clamping part 31 and the second clamping part 21 can be fixedly connected by means of bonding or the like. Alternatively, the first clamping part 31 may be movably disposed relative to the second clamping part 21. When it is not necessary to use the first clamping part 31 to press against the tab 132, the first clamping part 31 can be separated from the second clamping part 21. During the isostatic pressing of the electrode assembly 13, the first clamping part 31 can be placed between the second clamping part 21 and the tab 132. When the clamp 20 includes a support portion 22, the second clamping portion 21 can be directly disposed on the side of the support portion 22 facing the electrode assembly 13, and the first clamping portion 31 is located on the side of the second clamping portion 21 away from the support portion 22.

[0114] In the above scheme, the first clamping part 31 and the second clamping part 21 are arranged along the first direction X, and the first direction X is perpendicular to the thickness direction. This can reduce the mutual interference and influence between the first clamping part 31 and the second clamping part 21. When the first clamping part 31 and the second clamping part 21 press against the tab 132 and the electrode body 131 respectively during the isostatic pressing process of the electrode assembly 13, it helps to improve the stability of the tab 132 and the electrode body 131. Alternatively, the first clamping part 31 can be located on the side of the second clamping part 21 facing the electrode assembly 13. When the first clamping part 31 presses against the tab 132, the second clamping part 21 can generate a certain elastic buffering effect, thereby reducing the risk of stress concentration between the first clamping part 31 and the tab 132.

[0115] Please refer to Figures 4 to 6. In some embodiments, the first clamping part 31 includes a protruding sub-part 311, which protrudes from the side of the corresponding clamp 20 facing the electrode assembly 13. The thickness D of the protruding sub-part 311 satisfies: (hN*d) / 4≤D≤(hN*d) / 2, where h is the thickness of the electrode body 131 after isostatic pressing, N is the number of current collector layers in the electrode assembly 13, and d is the thickness of a single current collector layer in the electrode assembly 13.

[0116] Specifically, as shown in FIG4, when the first clamping part 31 and the second clamping part 21 are arranged along the first direction X, the first clamping part 31 may include a protruding sub-part 311 and a connecting sub-part 312 connected to each other. The connecting sub-part 312 is disposed on one side of the second clamping part 21 along the first direction X and is used to connect the second clamping part 21 and / or the support part 22. The protruding sub-part 311 may protrude along the second direction Y relative to the second clamping part 21 toward the side closer to the electrode assembly 13 and is used to contact the tab 132.

[0117] Alternatively, as shown in Figure 5, when the first clamping part 31 is disposed on one side of the second clamping part 21 along the second direction Y, the first clamping part 31 is a protruding sub-part 311, which protrudes from the side of the second clamping part 21 facing the electrode assembly 13.

[0118] Optionally, the thickness of the protruding sub-part 311 is greater than or equal to (hN*d) / 4 and less than or equal to (hN*d) / 2, where the thickness of the protruding sub-part 311 refers to the thickness of the protruding sub-part 311 in the second direction Y, and h can be the average thickness of the electrode bodies 131 of multiple electrode assemblies 13 after isostatic pressing, thereby achieving optimized design of the thickness of the protruding sub-part 311. Optionally, in the design and manufacturing process of the isostatic pressing fixture assembly provided in the embodiments of this application, multiple electrode assemblies 13 after isostatic pressing can be sampled first, for example, 32 to 60 electrode assemblies 13 can be sampled, the average thickness of the electrode body 131 of each electrode assembly 13 can be calculated, and then the thickness of the protruding sub-part 311 can be calculated based on the average thickness, the thickness of the single layer current collector in the electrode assembly 13, and the number of current collector layers.

[0119] In the above solution, by reasonably adjusting the thickness of the protruding part 311 of the first clamping part 31, the pressing effect of the first clamping part 31 on the tab 132 during the isostatic pressing process of the electrode assembly 13 can be improved, so that the first clamping part 31 can provide sufficient support for the tab 132 during the isostatic pressing process of the electrode assembly 13, thereby further reducing the risk of the tab 132 bulging and deforming during the isostatic pressing process.

[0120] Secondly, embodiments of this application provide an isostatic pressing system, including an isostatic pressing device and an isostatic pressing fixture assembly as described above. The isostatic pressing device is provided with a static pressure chamber, and the isostatic pressing fixture assembly is disposed within the static pressure chamber.

[0121] Specifically, the isostatic pressing device includes a static pressure chamber, which accommodates the electrode assembly 13 and the isostatic pressing fixture assembly, among other structures. The static pressure chamber can be filled with an isostatic medium. By adjusting parameters such as temperature and pressure within the static pressure chamber, isostatic pressing treatment of the electrode assembly 13 can be achieved. It should be noted that before performing isostatic pressing treatment on the electrode assembly 13, the electrode assembly 13 and the isostatic pressing fixture assembly can be assembled outside the static pressure chamber, and then the assembled electrode assembly 13 and the isostatic pressing fixture assembly can be moved together into the static pressure chamber. Alternatively, the electrode assembly 13 and the isostatic pressing fixture assembly can be assembled inside the static pressure chamber.

[0122] The isostatic pressing system provided in this application has the technical effects of the isostatic pressing fixture assembly in any of the above embodiments. The explanations of the same or corresponding structures and terms as in the above embodiments will not be repeated here.

[0123] Please refer to Figure 7. In a third aspect, embodiments of this application provide an isostatic pressing method for an electrode assembly 13. The isostatic pressing method includes:

[0124] S10. The two clamps 20 of the isostatic pressing clamp assembly are clamped on both sides of the electrode body 131 of the electrode assembly 13 along the thickness direction of the electrode assembly 13, and the limiting member 30 of the isostatic pressing clamp assembly is pressed against at least one side of the electrode tab 132 of the electrode assembly 13 along the thickness direction.

[0125] S20. Place the electrode assembly 13 and the isostatic pressing fixture assembly into the static pressure chamber of the isostatic pressing device for isostatic pressing treatment. Specifically, the static pressure chamber can be filled with a static pressure medium such as heat transfer oil. By adjusting parameters such as temperature, pressure, and static pressure time within the static pressure chamber, isostatic pressing treatment of the electrode assembly 13 can be achieved. After the isostatic pressing treatment is completed, move the electrode assembly 13 and the isostatic pressing fixture assembly outside the static pressure chamber, remove the isostatic pressing fixture assembly, and finally clean the electrode assembly 13 to complete the isostatic pressing treatment of the electrode assembly 13.

[0126] In the above scheme, the electrode body 131 is clamped from both sides by two clamps 20, and the tab 132 is pressed against at least one side along the thickness direction by the limiting member 30. Then, the electrode assembly 13 and the isostatic pressing fixture assembly are placed in the static pressing chamber for isostatic pressing treatment. This can reduce the assembly difficulty of the electrode assembly 13 and the isostatic pressing fixture assembly. In addition, during the isostatic pressing process, the clamping action of the two clamps 20 on the electrode body 131 can improve the stability and reliability of the electrode body 131 during the isostatic pressing process. The limiting action of the limiting member 30 on the tab 132 can reduce the risk of the tab 132 bulging and deforming along the thickness direction, which helps to improve the flatness of the electrode assembly 13, reduce the risk of stress concentration in the electrode assembly 13 in subsequent processes, and improve the performance of the electrode assembly 13 and the battery cell 10.

[0127] Optionally, in the isostatic pressing step, the pressure in the static pressing chamber is 200 MPa to 800 MPa, the temperature is 25°C to 150°C, and the static pressing time is 5 min to 30 min, so as to improve the isostatic pressing effect of the electrode assembly 13.

[0128] Optionally, when the limiting member 30 includes two first clamping parts 31, and the two first clamping parts 31 are respectively disposed on two clamps 20 and fixedly connected to the corresponding clamps 20, the two first clamping parts 31 and the two clamps 20 can be assembled first, and then the electrode assembly 13 can be fixed.

[0129] Optionally, when the limiting member 30 includes two first clamping parts 31, and the two first clamping parts 31 are respectively disposed on two clamps 20 and are movably disposed relative to the corresponding clamps 20, the step of clamping the two clamps 20 of the isostatic clamping fixture assembly on both sides of the electrode body 131 of the electrode assembly 13 along the thickness direction of the electrode assembly 13, and pressing the limiting member 30 of the isostatic clamping fixture assembly against at least one side of the tab 132 of the electrode assembly 13 along the thickness direction includes:

[0130] The first clamping part 31 is disposed on the first clamp 20, and the electrode assembly 13 is placed on one side of the first clamp 20, such that the electrode body 131 contacts the first clamp 20 on one side along the thickness direction, and the electrode tab 132 contacts the first clamping part 31 on one side along the thickness direction.

[0131] The second first clamping part 31 is placed on the side of the tab 132 away from the first first clamping part 31 along the thickness direction;

[0132] The second clamp 20 is placed on the side of the electrode body 131 away from the first clamp 20 along the thickness direction, and the second first clamping part 31 is located between the electrode tab 132 and the second clamp 20.

[0133] Connecting the first clamp 20 and the second clamp 20 achieves the fixation of the electrode assembly 13.

[0134] Referring to Figure 8, in some embodiments, during the step of pressing the limiting member 30 of the isostatic clamp assembly against at least one side of the electrode tab 132 of the electrode assembly 13 along the thickness direction,

[0135] The limiting member 30 is arranged at an interval from the electrode body 131.

[0136] In the above solution, by setting the limiting member 30 to be spaced apart from the electrode body 131 when pressing the tab 132, the risk of the limiting member 30 affecting the electrode active material in the electrode body 131 can be reduced, and the performance of the electrode body 131 can be improved.

[0137] Please continue referring to Figure 8. In some embodiments, during the step of pressing the limiting member 30 of the isostatic pressing fixture assembly against at least one side of the electrode tab 132 of the electrode assembly 13 along the thickness direction,

[0138] The distance H between the limiting member 30 and the electrode body 131 satisfies the condition: 2 mm ≤ H ≤ 10 mm. For example, the distance between the limiting member 30 and the electrode body 131 can be 2 mm, 4 mm, 5 mm, 7 mm, 10 mm, etc.

[0139] It should be noted that during the preparation of electrode assembly 13, when coating the active material onto the current collector, some of the active material may be coated onto the root of tab 132 (i.e., the part of tab 132 close to electrode body 131).

[0140] In the above scheme, the distance between the limiting member 30 and the electrode body 131 is greater than or equal to 2 mm and less than or equal to 10 mm. On the one hand, it can reduce the risk that the limiting member 30 will affect the active material at the root of the tab 132. On the other hand, it can also improve the limiting effect of the limiting member 30 on the tab 132 and reduce the risk of the tab 132 bulging and deforming during the isostatic pressing process.

[0141] Referring to Figures 9 and 10, in some embodiments, before the steps of clamping the two clamps 20 of the isostatic pressing fixture assembly on both sides of the electrode body 131 of the electrode assembly 13 along the thickness direction of the electrode assembly 13, and pressing the limiting member 30 of the isostatic pressing fixture assembly against at least one side of the tab 132 of the electrode assembly 13 along the thickness direction, the method further includes the following steps:

[0142] S30. The electrode assembly 13 is covered from the outside by the protective component 40. Part of the protective component 40 is located between the electrode assembly 13 and the isostatic pressing fixture assembly, that is, the isostatic pressing fixture assembly indirectly presses against the electrode assembly 13 through the protective component 40. Optionally, the protective component 40 can be a thin film structure, which reduces its impact on the isostatic pressing effect of the electrode assembly 13 while protecting it.

[0143] In the above scheme, the electrode assembly 13 is first covered from the outside by the protective component 40, and then the electrode assembly 13 covered by the protective component 40 is fixed by the isostatic clamping fixture assembly. During the isostatic pressing process of the electrode assembly 13, the protective component 40 can protect the electrode assembly 13, isolate the electrode assembly 13 and the isostatic medium filled in the static pressure cavity, thereby reducing the risk of the isostatic medium affecting the performance of the electrode assembly 13.

[0144] Referring to Figures 10 and 11, in some embodiments, the protective component 40 includes a first protective film 41 and a second protective film 42. The step of covering the electrode assembly 13 from the outside with the protective component 40 includes:

[0145] S31. The first protective film 41 and the second protective film 42 are disposed on both sides of the electrode assembly 13 along the thickness direction.

[0146] S32. The first protective film 41 and the second protective film 42 are sealed together circumferentially to cover the electrode assembly 13. There are various ways to seal the first protective film 41 and the second protective film 42, such as heat sealing or bonding.

[0147] In the above solution, the first protective film 41 and the second protective film 42 are disposed on both sides of the electrode assembly 13 along the thickness direction. Then, the first protective film 41 and the second protective film 42 are sealed together circumferentially, thereby covering the electrode assembly 13 and reducing the difficulty of the protective assembly 40 covering the electrode assembly 13. Furthermore, disposing of the first protective film 41 and the second protective film 42 on both sides of the electrode assembly 13 along the thickness direction ensures that the connection point of the first protective film 41 and the second protective film 42 is located outside the contact area between the electrode assembly 13 and the isostatic pressing fixture assembly, thus reducing the risk of indentation or other damage to the electrode assembly 13 under the action of the isostatic pressing fixture assembly.

[0148] Please continue referring to Figure 10. In some embodiments, both the side of the first protective film 41 facing the electrode assembly 13 and the side of the second protective film 42 facing the electrode assembly 13 are provided with receiving grooves K1.

[0149] In the step of setting the first protective film 41 and the second protective film 42 on both sides of the electrode assembly 13 along the thickness direction, a part of the electrode body 131 of the electrode assembly 13 is located in the receiving groove K1 of the first protective film 41, and the other part is located in the receiving groove K1 of the second protective film 42.

[0150] The shape of the receiving groove K1 is adapted to the shape of the electrode body 131. In the electrode assembly 13, the electrode body 131 is located in two receiving grooves K1, and the electrode tab 132 is located outside the receiving grooves K1. It can be covered by the first protective film 41 and the second protective film 42 except for the receiving grooves K1.

[0151] In the above solution, the first protective film 41 and the second protective film 42 are provided with receiving grooves K1, so that a part of the electrode body 131 is located in the receiving groove K1 of the first protective film 41 and the other part is located in the receiving groove K1 of the second protective film 42, which can reduce the risk of the first protective film 41 and the second protective film 42 causing damage to the electrode body 131.

[0152] This application provides an isostatic pressing fixture assembly, including two clamps 20 and a limiting member 30. The two clamps 20 are used to clamp the electrode body 131 of the electrode assembly 13 from both sides during the isostatic pressing process. The limiting member 30 is disposed on at least one side of the tab 132 of the electrode assembly 13 along the thickness direction during the isostatic pressing process. At least a portion of the limiting member 30 comprises an elastic material. The limiting member 30 includes two first clamping portions 31, which are respectively disposed on the two clamps 20. At least a portion of the first clamping portions 31 protrudes from the clamp 20 on the side facing the electrode assembly 13 and is used to press against the tab 132. The clamps 20 include second clamping portions 21, at least a portion of which comprises an elastic material and is used to press against the electrode body 131. The Shore hardness of the second clamping portion 21 is greater than that of the first clamping portion 31. The clamp 20 also includes a support portion 22, and at least one of the first clamping portion 31 and the second clamping portion 21 is disposed on the support portion 22 and located on the side of the support portion 22 facing the electrode assembly 13.

[0153] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not 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 modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. An isostatic pressure fixture assembly, comprising: Two clamps are used to hold the electrode body of the electrode assembly from both sides of the electrode assembly in the thickness direction during the isostatic pressing process of the electrode assembly; A limiting member is provided on at least one side of the tab of the electrode assembly along the thickness direction during the isostatic pressing process.

2. The isostatic press clamp assembly of claim 1, wherein, At least a portion of the limiting member comprises an elastic material.

3. The isostatic pressing fixture assembly according to claim 1 or 2, wherein, The limiting member includes two first clamping parts, which are used to press against both sides of the electrode tab along the thickness direction during the isostatic pressing process.

4. The isostatic pressing fixture assembly according to claim 3, wherein, The two first clamping parts are respectively disposed on the two clamps, and at least a portion of the first clamping part protrudes from the side of the clamp facing the electrode assembly and is used to press against the electrode tab.

5. The isostatic pressing fixture assembly according to claim 3 or 4, wherein, The clamp includes a second clamping portion, at least a portion of which comprises an elastic material, and the second clamping portion is used to press against the electrode body.

6. The isostatic pressing fixture assembly according to claim 5, wherein, The Shore hardness of the second clamping part is greater than that of the first clamping part.

7. The isostatic pressing fixture assembly according to claim 5 or 6, wherein, The elastic modulus of the second clamping part is greater than that of the first clamping part.

8. The isostatic pressing fixture assembly according to any one of claims 5 to 7, wherein, The clamp further includes a support portion, on which at least one of the first clamping portion and the second clamping portion is disposed and located on the side of the support portion facing the electrode assembly.

9. The isostatic pressing fixture assembly according to claim 8, wherein, At least one of the first clamping portion and the second clamping portion is bonded to the support portion.

10. The isostatic pressing fixture assembly according to any one of claims 5 to 9, wherein, The first clamping portion and the second clamping portion are arranged along a first direction, which is perpendicular to the thickness direction; or... The first clamping portion is disposed on the side of the second clamping portion facing the electrode assembly along a second direction, the second direction being parallel to the thickness direction.

11. The isostatic pressing fixture assembly according to any one of claims 4 to 10, wherein, The first clamping portion includes a protruding sub-portion that protrudes from the side of the clamp facing the electrode assembly. The thickness D of the protruding sub-part satisfies: (hN*d) / 4≤D≤(hN*d) / 2, where h is the thickness of the electrode body after isostatic pressing, N is the number of current collector layers in the electrode assembly, and d is the thickness of a single current collector layer in the electrode assembly.

12. An isostatic pressure system, comprising: The isostatic pressing device is equipped with a static pressure chamber; The isostatic pressure clamp assembly as described in any one of claims 1 to 11, wherein the isostatic pressure clamp assembly is disposed within the static pressure chamber.

13. An isostatic pressing method for an electrode assembly, the isostatic pressing method comprising: The two clamps of the isostatic pressing clamp assembly are clamped on both sides of the electrode body of the electrode assembly along the thickness direction of the electrode assembly, and the limiting member of the isostatic pressing clamp assembly is pressed against at least one side of the electrode tab of the electrode assembly along the thickness direction. The electrode assembly and the isostatic clamp assembly are placed in the static pressure chamber of the isostatic pressing device for isostatic pressing treatment.

14. The isostatic pressing method according to claim 13, wherein, In the step of pressing the limiting member of the isostatic clamp assembly against at least one side of the electrode lug of the electrode assembly along the thickness direction, The limiting member is arranged at a distance from the electrode body.

15. The isostatic pressing method according to claim 14, wherein, In the step of pressing the limiting member of the isostatic clamp assembly against at least one side of the electrode lug of the electrode assembly along the thickness direction, The distance H between the limiting member and the electrode body satisfies: 2 mm ≤ H ≤ 10 mm.

16. The isostatic pressing method according to any one of claims 13 to 15, wherein, Before the steps of clamping the two clamps of the isostatic pressing fixture assembly on both sides of the electrode body of the electrode assembly along the thickness direction of the electrode assembly, and pressing the limiting member of the isostatic pressing fixture assembly against at least one side of the electrode tab of the electrode assembly along the thickness direction, the method further includes the step of: The electrode assembly is covered from the outside by a protective component.

17. The isostatic pressing method according to claim 16, wherein, The protective component includes a first protective film and a second protective film, and the step of covering the electrode assembly from the outside with the protective component includes: The first protective film and the second protective film are disposed on both sides of the electrode assembly along the thickness direction; The first protective film and the second protective film are circumferentially sealed together to cover the electrode assembly.

18. The isostatic pressing method according to claim 17, wherein, Both the first protective film and the second protective film have receiving grooves on the side facing the electrode assembly. In the step of disposing the first protective film and the second protective film on both sides of the electrode assembly along the thickness direction, A portion of the electrode body of the electrode assembly is located within the receiving groove of the first protective film, and another portion is located within the receiving groove of the second protective film.

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