Hot-pressing formation device for improving broken pieces of wound battery cell
By setting a thermally conductive pad and a matte surface on the metal plate of the hot pressing device, the problem of easy breakage of the battery cell ear during the high-temperature jig formation process is solved, and a safe and reliable battery cell transformation process is achieved.
Patent Information
- Application Number
- CN202421500069.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-28
- Publication Date
- 2025-05-16
- Estimated Expiration
- 2034-06-28
AI Technical Summary
During the high-temperature jig formation process, since the upper and lower pressure plates of existing equipment are hard heated steel plate structures, the battery cell ears are easily broken, causing risks such as chip breakage and short circuit.
A thermal compression forming device for improving the broken chip of the winding battery cell is designed. By providing a thermal pad on the metal plate in contact with the electrode of the battery cell, the buffering metal plate directly acts on the instantaneous pressure of the battery cell, and increases friction through the frosted surface to prevent sliding and bubble formation.
It effectively avoids the battery cell's extreme ear pressure due to excessive stress in an instant, prevents risks such as chip breakage and short circuit, and ensures the transformation effect and saves costs.
Smart Images
Figure CN222883603U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of battery manufacturing, in particular to a device for improving the hot pressing and forming of wound battery core fragments. Background Art
[0002] High-temperature fixture formation, also known as hot pressing formation, is based on the principle of hot pressing soft-pack lithium-ion batteries under high temperature and high pressure to complete the battery manufacturing process. Compared with normal temperature formation, formation at high temperature can significantly increase the diffusion rate of lithium ions, so that the protective layer evenly fills the pore area of the entire battery electrode, thereby giving full play to the performance of the lithium-ion battery.
[0003] Nowadays, due to the size limitation of the battery cell width, some soft-pack lithium-ion batteries adopt an external tab structure, such as Figure 2 As shown in the figure, the positive and negative pole tabs are located at the outermost layer of the outermost cell after winding. At present, when such cells are subjected to high-temperature fixture formation, the upper and lower pressure plates of the existing formation equipment are both hard heated steel plate structures (such as Figure 5 As shown in the figure, the upper and lower steel plates directly apply pressure to the battery body, and because the battery adopts a winding structure design (such as Figure 2 As shown in the figure, the tab is located at the outermost layer of the battery cell and is the thickest part in the thickness direction of the battery. During the high-temperature fixture formation, the pressure of the hard steel plate directly acts on the tab position and is transmitted inward at the same time, which can easily cause the tab to break the electrode piece, causing the battery cell to break, short circuit and other risks. Utility Model Content
[0004] In view of this, in order to solve the above problems, the utility model provides a device for effectively improving the hot pressing of wound battery core fragments.
[0005] A hot pressing forming device for improving wound battery cell fragments is used for forming the battery cell. The battery cell tabs are distributed on the same side. The forming device comprises a first metal plate and a second metal plate arranged opposite to each other. Two groups of the metal plates are connected to a heating device. The contact surface of one group of the metal plates in contact with one side of the battery cell tab is covered with a thermally conductive pad. The thermally conductive pad is provided with a frosted surface, which faces and fits the metal plate.
[0006] In the above technical solution, the heating device can heat the metal plate to make it in a high temperature state, and then hot press the battery cell placed between the two groups of metal plates to complete the high temperature formation treatment, wherein the pole ears of the battery cell are distributed on the same side of the battery cell. In this way, it is only necessary to set a thermally conductive pad on the metal plate in contact with one side of the pole ear of the battery cell, and there is no need to set a thermally conductive pad on both groups of metal plates, which can save a certain cost. The thermally conductive pad is made of a thermally conductive material and can transfer heat to the battery cell body, which will not affect the heat demand of the battery cell during formation. The thermally conductive pad is a soft structure with a certain elasticity, which can buffer the instantaneous pressure of the metal plate directly acting on the battery cell during hot pressing. , to avoid the battery cell being subjected to excessive force in an instant, which may cause the pole ear to break the pole piece, causing the battery cell to break, short circuit and other risks. In addition, the side of the thermal conductive pad that fits the metal plate is a frosted surface that has been frosted. Since the surface of the metal plate is relatively smooth, the frosted surface can increase the friction between the metal plate and prevent relative sliding. At the same time, due to the high temperature during high-temperature formation, the air between the thermal conductive pad and the metal plate is easily expanded to form bubbles after being heated, affecting the conduction of heat, thereby affecting the formation effect. The frosted surface, due to its uneven surface, can form gaps and channels for air to pass through, helping to discharge the air between the thermal conductive pad and the metal plate to ensure the formation effect.
[0007] As an optional technical solution of the present application, the thermally conductive pad further includes a bright surface arranged opposite to the frosted surface, and the bright surface faces and contacts with the battery cell.
[0008] In the above technical solution, one side of the thermally conductive pad is a frosted surface, and the other side is a glossy surface. The surface of the glossy surface is flat and is used to contact the battery cell, so that the surface of the battery cell will not be damaged during hot pressing treatment, thereby ensuring the flatness of the battery cell.
[0009] As an optional technical solution of the present application, the battery cell is a winding structure, the tabs of the battery cell are distributed on the outermost layer on the same side, and one side of the tab of the battery cell is in contact with the bright surface of the thermally conductive pad.
[0010] In the above technical solution, the battery cell is wound, and after winding, the pole ear is located at the outermost layer on the same side of the battery cell. In this way, it is only necessary to set a thermal conductive pad on the metal plate in contact with one side of the battery cell pole ear, which can save a certain cost. When the battery cell is hot pressed, one side of the battery cell pole ear faces the direction of the thermal conductive pad and contacts with the bright surface of the thermal conductive pad, avoiding the risk of breakage, short circuit, etc. caused by direct rigid contact between the pole ear and the metal plate.
[0011] As an optional technical solution of the present application, the thermally conductive pad is an elastic structure with elastic deformation capability.
[0012] In the above technical solution, the thermally conductive pad is made of silicone or other elastic materials, has good elastic deformation ability, and can better buffer the pressure directly brought to the battery cell by the metal plate.
[0013] As an optional technical solution of the present application, the two groups of metal plates are arranged up and down, and the thermal conductive pad is arranged on the metal plate on the lower side.
[0014] In the above technical solution, two groups of metal plates are arranged up and down, and the thermal conductive pads are distributed on the contact surface of the lower metal plate. During high-temperature forming, the battery cell is placed on the thermal conductive pad of the lower metal plate, and one side of the pole ear is in contact with the thermal conductive pad.
[0015] As an optional technical solution of the present application, the metal plate on the upper side is connected to a driving mechanism, and the driving mechanism is used to drive the metal plate on the upper side to perform lifting movements.
[0016] In the above technical solution, the output end of the driving mechanism is connected to the metal plate on the upper side, and the driving mechanism drives the metal plate on the upper side to move up and down to apply pressure to the battery cell.
[0017] As an optional technical solution of the present application, the metal plate is a hard steel plate.
[0018] In the above technical solution, the metal plate is a hard steel plate to ensure that the pressure applied at each position is uniform.
[0019] The present application is provided with two groups of metal plates for high-temperature hot pressing of battery cells. By arranging a thermally conductive pad on one of the groups of metal plates, the instantaneous pressure of the metal plate directly acting on the battery cell is buffered during hot pressing, so as to avoid the battery cell being subjected to excessive force in an instant and causing the pole ear to break the pole piece, thereby preventing the battery cell from breaking, short circuiting and other risks. In addition, the side of the thermally conductive pad that is in contact with the metal plate is a frosted surface that has been frosted. Since the surface of the metal plate is relatively smooth, the frosted surface can increase the friction between the metal plate and the metal plate to prevent relative sliding. At the same time, since the temperature during high-temperature forming is high, the air between the rubber pad and the metal plate is easily expanded to form bubbles after being heated, which affects the conduction of heat and thus affects the forming effect. The frosted surface, due to its uneven surface, can form gaps and channels for air to pass through, thereby helping to discharge the air between the thermally conductive pad and the metal plate and ensuring the forming effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0021] Figure 1 Schematic diagram of the structure of a formation device according to an embodiment.
[0022] Figure 2 It is a structural schematic diagram of the battery cell.
[0023] Figure 3 It is a front view of the thermally conductive pad.
[0024] Figure 4 for Figure 3 Right side view.
[0025] Figure 5 The invention relates to a structure of a high-temperature fixture forming device in the prior art.
[0026] Description of reference numerals in the figures:
[0027] 1-metal plate; 2-thermal conductive pad; 21-frosted surface; 22-bright surface; 3-battery cell; 31-ear; 4-driving mechanism. DETAILED DESCRIPTION
[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.
[0029] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.
[0030] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings. Example
[0031] Please refer to Figures 1 to 4In a preferred embodiment of the present application, the present embodiment provides a hot pressing forming device for improving the wound battery cell fragment, which is used for forming the battery cell 3. The pole ears 31 of the battery cell 3 are distributed on the same side. The forming device includes two groups of metal plates 1. In order to facilitate the placement of the battery cell 3, the two groups of metal plates 1 are arranged up and down. The two groups of metal plates 1 are connected to a heating device (not shown in the figure). The contact surface of the metal plate 1 located on the lower side that contacts one side of the pole ear 31 of the battery cell 3 is covered with a thermally conductive pad 2. The thermally conductive pad 2 is provided with a frosted surface 21, and the frosted surface 21 faces and fits with the metal plate 1.
[0032] In this embodiment, the heating device can heat the metal plate 1 to make it in a high temperature state, and then hot press the battery cell 3 placed between the two groups of metal plates 1 to complete the high temperature formation treatment, wherein the battery cell 3 is wound, and its pole ears 31 are distributed on the same side. In this way, it is only necessary to set a thermally conductive pad 2 on the lower metal plate 1, and there is no need to set a thermally conductive pad 2 on both groups of metal plates 1, which can save a certain cost. The thermally conductive pad 2 is made of a thermally conductive material and can transfer heat to the battery cell 3 body, and will not affect the heat demand of the battery cell 3 during formation. The thermally conductive pad 2 is a soft structure with a certain elasticity, which can buffer the instantaneous pressure directly exerted by the metal plate 1 on the battery cell 3 during hot pressing, and avoid the battery cell 3 being affected by the instantaneous Excessive force causes the pole ear 31 to break the pole piece, causing the risk of breakage and short circuit in the battery cell 3. In addition, the side of the thermal pad 2 that contacts the metal plate 1 is a frosted surface 21 that has been frosted. Since the surface of the metal plate 1 is relatively smooth, the frosted surface 21 can increase the friction between the metal plate 1 and prevent relative sliding. At the same time, since the temperature during high-temperature formation is high (the specific temperature is 82±5°C), the air between the thermal pad 2 and the metal plate 1 is easily expanded to form bubbles after being heated, affecting the conduction of heat and thus affecting the formation effect. Since the frosted surface 21 has an uneven surface, it can form gaps and channels for air to pass through, helping to discharge the air between the thermal pad 2 and the metal plate 1 and ensuring the formation effect.
[0033] It should be noted that, in order to facilitate the placement of the battery cells 3, the two sets of metal plates 1 are arranged up and down, and the battery cells 3 are directly placed on the thermal conductive pad 2 of the lower metal plate 1 during the formation, wherein multiple battery cells 3 can be placed at the same time for formation (such as Figure 1 to improve efficiency.
[0034] Specifically, in the present embodiment, each group includes only one metal plate 1. In addition, it can also be formed by splicing a plurality of metal plates, or other connection methods that can move together, which are not specifically limited here.
[0035] Reference Figure 3 and Figure 4In some embodiments, the other side of the thermal pad 2 opposite to the frosted surface 21 is a bright surface 22. The frosted surface 21 is used to contact the surface of the metal plate 1, and the bright surface 22 is used to contact the surface of the battery cell 3. The surface of the bright surface 22 is smooth, so that the surface of the battery cell 3 will not be damaged during the hot pressing process, thereby ensuring the flatness and appearance quality of the battery cell 3.
[0036] Reference Figure 2 In some embodiments, the battery cell 3 is a multi-layer structure formed by winding, and the pole ears 31 of the battery cell 3 are distributed on the outermost layer on the same side. In this way, it is only necessary to set the thermal conductive pad 2 on the lower metal plate 1, which can save a certain cost. During the formation, one side of the pole ear 31 of the battery cell 3 faces the direction of the thermal conductive pad 2 and contacts with the bright surface 22 of the thermal conductive pad 2, avoiding the risk of the pole ear 31 directly contacting the metal plate 1 rigidly, resulting in the risk of breakage, short circuit, etc.
[0037] It should be noted that Figure 2 The battery cell 3 is provided with two pole tabs 31, and the two pole tabs 31 are both located on the same side of the battery cell 3. In addition, the present application can also be applied to the formation of multi-pole tab batteries.
[0038] In some embodiments, the thermally conductive pad 2 is an elastic structure with elastic deformation ability. Preferably, the thermally conductive pad 2 is made of silicone, which has good elastic deformation ability and can better buffer the pressure directly brought to the battery cell 3 by the metal plate 1 to prevent breakage. In addition to silicone, other materials with elastic and thermally conductive properties can also be used, and there is no specific limitation here.
[0039] Specifically, in some embodiments, the thickness of the thermally conductive pad 2 is 1.0 mm, and the hardness is 60 degrees Shore A, and the thickness and hardness parameters are determined according to actual conditions.
[0040] Reference Figure 1 In some embodiments, the metal plate 1 on the upper side is connected to a driving mechanism 4, the output end of the driving mechanism 4 is connected to the metal plate 1 on the upper side, and the driving mechanism 4 drives the metal plate 1 on the upper side to move up and down to apply pressure to the battery cell 3; the driving mechanism 4 can be a cylinder, a linear motor, etc.
[0041] In some embodiments, the metal plate 1 is a hard steel plate, and the hard structure can ensure that the pressure at each position is uniform when the metal plate 1 applies pressure.
[0042] Please refer to Figure 1 The specific steps of using this formation device are as follows:
[0043] First, the upper metal plate is lifted by the driving mechanism 4, and the battery cell 3 to be formed is placed on the lower metal plate with the pole ear 31 side facing downward. After the placement is completed, the heating device heats the two groups of metal plates 1 to a suitable temperature, and then the driving mechanism 4 drives the upper metal plate to move downward to apply a preset pressure to the battery cell 3. After a certain period of time, the driving mechanism 4 drives the upper metal plate to move up to complete the formation process.
[0044] In the description of the present invention, it should be understood that terms such as "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0045] In addition, in the description of the present invention, “plurality” means two or more than two, unless otherwise clearly and specifically defined.
[0046] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0047] Although the utility model is described in conjunction with the above specific embodiments, it is obvious that those skilled in the art can make many substitutions, modifications and changes based on the above content. Therefore, all such substitutions, improvements and changes are included in the spirit and scope of the appended claims.
Claims
1. A hot pressing forming device for improving the wound battery cell fragment, used for forming the battery cell, wherein the tabs of the battery cell are distributed on the same side, characterized in that: The formation device includes two groups of metal plates arranged opposite to each other, the two groups of metal plates are connected to a heating device, and the contact surface of one group of metal plates that contacts one side of the battery cell ear is covered with a thermally conductive pad, and the thermally conductive pad is provided with a frosted surface, which faces and fits the metal plate.
2. The hot pressing forming device for improving the wound battery core fragment according to claim 1, characterized in that: The thermally conductive pad also includes a bright surface arranged opposite to the frosted surface, and the bright surface faces and contacts with the battery core.
3. The hot pressing forming device for improving the wound battery core fragment according to claim 2, characterized in that: The battery core is a winding structure, the tabs of the battery core are distributed on the outermost layer on the same side, and one side of the tab of the battery core is in contact with the bright surface of the thermally conductive pad.
4. The device for improving the hot pressing of wound battery core fragments according to claim 1, characterized in that: The thermally conductive pad is an elastic structure with elastic deformation capability.
5. The device for improving the hot pressing of wound battery core fragments according to claim 1, characterized in that: The two groups of metal plates are arranged up and down, and the thermal conductive pad is arranged on the metal plate at the lower side.
6. The device for improving the hot pressing of wound battery core fragments according to claim 5, characterized in that: The metal plate on the upper side is connected to a driving mechanism, and the driving mechanism is used to drive the metal plate on the upper side to perform lifting movement.
7. The device for improving the hot pressing of wound battery core fragments according to claim 1, characterized in that: The metal plate is a hard steel plate.