Cover plate assembly and power battery

Abstract

The invention relates to the technical field of power batteries, and provides a cover plate assembly and a power battery. The cover plate assembly comprises a cover plate, a pole penetrating through the cover plate and lower plastic which is arranged on one side of the cover plate and can insulate the cover plate and the pole, an anti-explosion valve can be installed on the cover plate, and the lower plastic comprises a lower plastic body arranged along with the cover plate and a protection part connected with the lower plastic body in the width direction of the lower plastic body; a buckle on the protection part penetrates through the lower plastic body and is connected with the cover plate in a clamped mode, the protection part is arranged on the side, opposite to the cover plate, of the lower plastic body in a blocking mode, the lower plastic body and the protection part are provided with open holes corresponding to the anti-explosion valve, and the protection part is provided with a cavity corresponding to the pole. According to the cover plate assembly disclosed by the invention, the protection part can be connected with the cover plate in a clamping manner, the connection stability and reliability are relatively high, welding slag of the pole and the tab can be well prevented from puncturing the diaphragm, and the safety and reliability of the power battery can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of power batteries, and in particular to a cover plate assembly. The present application also relates to a power battery using the cover plate assembly. Background Art

[0002] During the battery manufacturing process, the electrode group is installed in the shell of the power battery. The welding of the electrode tabs in the electrode group and the upper cover of the shell is one of the key processes, and the welding quality directly affects the safety and performance of the battery.

[0003] Specifically, the electrode group includes a positive electrode sheet, a negative electrode sheet, and a diaphragm that insulates the positive and negative electrode sheets. Among them, the diaphragm is a key component that separates the positive and negative electrodes in the battery.

[0004] In existing power batteries, under harsh conditions, the electrode assembly is prone to vertical vibration within the battery casing, posing a risk of puncturing the diaphragm. Once the diaphragm is punctured by welding slag from the tab to the cover plate, the positive and negative electrodes come into direct contact, creating a short circuit. The high temperatures generated by this short circuit can trigger a chain reaction within the battery, such as decomposition of the electrolyte and electrode materials, potentially leading to thermal runaway. Thermal runaway can not only damage the battery but also pose a threat to the surrounding environment and personnel safety. Summary of the Invention

[0005] In view of this, the present application aims to propose a cover plate assembly to improve the safety and reliability of power batteries.

[0006] To achieve the above objectives, the technical solution of this application is implemented as follows: A cover plate assembly includes a cover plate, a pole arranged through the cover plate, and a lower plastic provided on one side of the cover plate and capable of insulating the cover plate and the pole; The cover plate is in an elongated strip shape, and an explosion-proof valve can be installed on the cover plate; The lower plastic comprises a lower plastic body arranged in accordance with the cover plate, and a protective portion connected to the lower plastic body in the width direction of the lower plastic body; The protective portion extends along the length direction of the lower plastic body, and is provided with a buckle on the protective portion. The lower plastic body is provided with a through hole, and the clamping portion of the buckle can pass through the through hole and be clamped and connected to the lower plastic body, so that the protective portion is blocked on the side of the lower plastic body facing away from the cover plate; The lower plastic body and the protective part are both provided with openings corresponding to the explosion-proof valve. The protective part is provided with a cavity corresponding to the pole. One side of the cavity is open, and the open side faces the lower plastic body.

[0007] Furthermore, a snap-fitting hole is provided on the cover plate, and the snap-fitting hole is a blind hole. The snap-fitting portion of the buckle can pass through the through hole and be snapped into the snap-fitting hole.

[0008] Furthermore, the lower plastic body has a first protrusion protruding toward one side of the protective portion, and the through hole is provided at the first protrusion and passes through the lower plastic body.

[0009] Furthermore, the protective portion has a central area corresponding to the pole and an edge area surrounding the central area; the cavity is formed by the central area being recessed toward a side away from the lower plastic body, and the central area is used to press against the pole group.

[0010] Furthermore, the middle region and the edge region are connected by connecting ribs, and the connecting ribs are multiple and spaced around the middle region.

[0011] Furthermore, the protective portion is connected to the lower plastic body via a bent portion, and the protective portion, the bent portion and the lower plastic body are integrally formed through an injection molding process.

[0012] Furthermore, a glue reducing groove is provided on the bent portion; and / or a through hole is provided on the bent portion.

[0013] Furthermore, the cover plate is provided with a mounting hole for the pole to pass through, and a sealing ring is provided between the pole and the cover plate to seal the gap between the two; the pole includes a cylindrical pole body, and a first boss and a second boss provided on the outer periphery of the pole body; in a direction orthogonal to the axial direction of the pole body, the first boss and the second boss both protrude outward from the pole body, and the outer diameter of the first boss and the outer diameter of the second boss are both larger than the aperture of the mounting hole.

[0014] Furthermore, the mounting hole includes a first mounting hole and a second mounting hole that are connected; the aperture of the first mounting hole is smaller than the aperture of the second mounting hole, and the second mounting hole is located on the side of the cover plate facing the lower plastic; the sealing ring is installed at the first mounting hole, and the lower plastic body is provided with a second protrusion embedded in the second mounting hole, and the second protrusion surrounds the periphery of the pole.

[0015] Compared with the existing technology, this application has the following advantages: (1) The cover assembly described in the present application is characterized by the lower plastic comprising a lower plastic body and a protective portion, and the protective portion is connected to the cover by passing through the lower plastic body through the clip on the protective portion. The reliability of the clip connection between the cover and the protective portion is high, so that the protective portion can be firmly placed on the side of the corresponding pole tab facing away from the cover. When applied to a power battery, it can better prevent the welding slag of the pole column and the pole tab from puncturing the diaphragm. The opening corresponding to the explosion-proof valve is provided, which is conducive to improving the reliability of the explosion-proof valve application. The cavity provided can provide sufficient space to cover the welding parts of the pole column and the pole tab, which can further prevent the diaphragm from being punctured, further reduce the risk of puncturing the diaphragm, and improve the safety and reliability of the power battery.

[0016] Each protective part is connected to the cover by snap-fitting, which is a quick connection method. Compared with traditional threaded connections, welding, etc., it does not require complicated tools and operating procedures. Using the snap-fit ​​method, after the protective part is aligned with the lower plastic body, assembly can be completed with a light push or press, which can greatly improve production efficiency. When it is necessary to disassemble, repair or replace the protective part, it is also only necessary to apply a certain external force to release the snap-fit ​​relationship, and the protective part can be easily removed, which is convenient and quick. Because the snap-fit ​​operation is simple and easy to learn, and the skill requirements for the operator are low, the company does not need to invest a lot of time and money in professional training for employees. This allows the company to arrange production personnel more flexibly and reduce labor costs. At the same time, the rapid assembly and disassembly process can also shorten the production cycle, improve equipment utilization, and further reduce production costs.

[0017] (2) The snap-in holes on the cover are set as blind holes. There is no need to worry about electrolyte leakage at the snap-in holes, nor is there any need to worry about external impurities entering the power battery through the snap-in holes. This can better improve the safety and reliability of the cover application. The snap-in parts will not be exposed, which can better ensure the appearance quality of the cover.

[0018] (3) By providing a first protrusion on the protective part and providing a through hole on the first protrusion and passing through the protective part, the thickness of the through hole portion can be increased. When the cover plate and the protective part are connected by snapping, the hole wall of the through hole can play a certain fixing role on the buckle in the radial direction of the buckle, which can better prevent the buckle from shaking, thereby further improving the stability and reliability of the snap connection between the cover plate and the protective part.

[0019] (4) The middle area is recessed toward the side away from the cover plate to form a cavity. The structure is simple, the processing is convenient, and the material consumption is small. When the electrode assembly is used in a power battery, the middle area is convenient for abutting the electrode group in the power battery, which can limit the position of the electrode group and help to attenuate the vibration of the electrode group, thereby reducing the risk of the electrode ear tearing and puncturing the diaphragm.

[0020] (5) The middle area is connected to the edge through connecting ribs, and gaps are formed between adjacent connecting ribs, which allows the electrolyte to flow through the gaps. In addition, this connection method is also conducive to the vibration of the middle area, which can have a good buffering effect on the vibration of the electrode group, and can further reduce the risk of the tab tearing and puncturing the diaphragm. The material consumption is also less, which is conducive to cost saving.

[0021] (6) The protective part is connected to the lower plastic body through the bending part, so that the protective part can be bent relative to the lower plastic body through the bending part, and it is easy to ensure the degree of fit between the protective part and the lower plastic body, which plays a certain role in fixing and shaping the pole ear, and can better reduce the risk of the pole ear tearing. The protective part, the bending part and the lower plastic body are integrally formed through the injection molding process, which is convenient to process. This one-piece lower plastic is also convenient to assemble and use during application, which can reduce the number of parts and facilitate management. At the same time, the lower plastic processed by the injection molding process, in addition to having good insulation and protection properties, is not easily punctured by the welding slag of the pole and the pole ear, thereby effectively reducing the risk of the welding slag puncturing the diaphragm.

[0022] (7) Setting a glue reduction groove on the bending part and setting a through hole on the bending part are both easy to process and are conducive to the smooth bending of the bending part. The material consumption is also good, which is conducive to cost saving.

[0023] (8) The pole includes a pole body, a first boss, and a second boss. The outer diameter of the first boss and the outer diameter of the second boss are both larger than the diameter of the mounting hole, so that the pole can be firmly mounted on the cover plate, thereby improving the installation and reliability of the power battery application. The sealing ring can effectively improve the sealing performance of the gap between the cover plate and the pole, prevent electrolyte leakage, and prevent external impurities from entering the power battery through the mounting hole, thereby further improving the installation and reliability of the power battery application.

[0024] (9) The mounting hole includes a first mounting hole and a second mounting hole that are connected to each other, and the aperture of the first mounting hole is limited to be smaller than the aperture of the second mounting hole. The second mounting hole is located on the side of the cover plate facing the lower plastic relative to the first mounting hole. A sealing ring is installed at the first mounting hole to form a seal, and the second protrusion on the lower plastic body is embedded in the second mounting hole to form a second seal. The two seals are formed, and the two seals are stepped, which can better improve the sealing effect between the cover plate and the pole.

[0025] Another object of the present application is to provide a power battery, wherein the housing of the power battery is provided with the cover plate assembly as described above.

[0026] Compared with the existing technology, this application has the following advantages: The power battery described in the present application, by applying the above cover plate assembly, has the same beneficial effects as the aforementioned cover plate assembly relative to the prior art, and will not be described in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings: Figure 1 This is an exemplary structural diagram of the cover assembly in an application state according to an embodiment of the present application; Figure 2 for Figure 1 Schematic diagram of the structure from another perspective; Figure 3 For the Figure 2 Cross-sectional view along line AA; Figure 4 for Figure 3 Magnified view of part C; Figure 5 for Figure 3 An enlarged view of the D portion; Figure 6 For the Figure 2 Cross-sectional view along the midline BB; Figure 7 for Figure 6 A magnified view of part E; Figure 8 This is an exemplary structural diagram of the electrode group, cover plate and lower plastic assembly process according to an embodiment of the present application; Figure 9 for Figure 8 Schematic diagram of the structure where the middle protective part is bent to one side of the lower plastic body; Figure 10 This is an exemplary structural diagram of the assembly process of the cover plate and the lower plastic according to an embodiment of the present application; Figure 11 for Figure 10 Magnified view of part F; Figure 12 for Figure 10 Schematic diagram of the structure from another perspective; Figure 13 for Figure 12 Magnified view of the G section.

[0028] Description of reference numerals: 1. Cover plate; 2. Lower plastic; 3. Pole group; 4. Sealing ring; 5. Pole; 6. Upper plastic; 7. Explosion-proof valve; 8. Protective film; 101. Mounting hole; 102. Snap-fit ​​hole; 103. Third protrusion; 1011, first mounting hole; 1012, second mounting hole; 1013, third mounting hole; 1021, first card hole; 1022, second card hole; 201, lower plastic body; 202, protective part; 203, bending part; 2011, buckle; 2014, via hole; 2015, first protrusion; 2016, second protrusion; 20111, split buckle; 20112, connecting block; 20113, connecting block; 2021, middle area; 2022, edge area; 2023, cavity; 2025, connecting rib; 2026, mounting hole; 2027, opening; 20271, first opening; 20272, second opening; 2031, glue reduction tank; 301, extreme ears; 501, pole body; 502, first boss; 503, second boss. DETAILED DESCRIPTION

[0029] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0030] In the description of this application, it should be noted that if terms such as "upper," "lower," "inner," and "outer" appear to indicate orientation or positional relationships, these are based on the orientation or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this application and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, if terms such as "first" and "second" appear, they are used solely for descriptive purposes and should not be construed as indicating or implying relative importance.

[0031] Furthermore, in the description of this application, unless otherwise explicitly defined, the terms "mounted," "connected," "connect," and "connector" should be interpreted broadly. For example, they can refer to fixed, removable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0032] The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0033] Within the battery manufacturing process, the welding process between the tab and the cover plays a crucial role, being one of the core steps that determine the final quality of the battery. The quality of this welding process is closely and directly correlated with the safety and electrochemical performance of the battery. Its quality plays a decisive role in the battery's ability to operate stably and safely in complex and changing operating environments.

[0034] A deeper analysis of the battery's internal microstructure reveals that the separator, a key functional component that effectively separates the positive and negative electrodes within the battery, possesses material properties and structural integrity that are crucial to the battery's safe and stable operation. Typically made of insulating materials with a specific porosity and mechanical strength, the separator's function is to strictly prevent direct contact between the positive and negative electrodes while ensuring normal ion transmission, thereby maintaining the orderly electrochemical reactions within the battery.

[0035] However, during the welding process between the tab and the electrode cap, slag is easily generated at the welding site due to factors such as slight fluctuations in welding process parameters (such as welding current, welding time, welding pressure, etc.), precision deviations in welding equipment, and differences in operator skills. The shape, size, and distribution of this slag are uncertain, and it may appear in the weld area in the form of tiny particles, flakes, or irregular shapes.

[0036] Existing power batteries are susceptible to vibration of the electrode assembly up and down the battery casing under harsh conditions, posing a risk of tab tearing. During assembly, transportation, or use, if the battery becomes dislodged or displaced due to subtle internal vibrations, stress changes, or external impact, welding slag can physically puncture the diaphragm. Once the diaphragm is punctured by welding slag, the separation between the positive and negative electrodes, maintained by the diaphragm, is broken, allowing direct electrical contact between the positive and negative electrodes and resulting in a short circuit.

[0037] When a short circuit occurs, a very large short-circuit current flows through the battery in a very short period of time. This high current, driven by the battery's internal resistance, rapidly generates a large amount of heat, causing the battery's internal temperature to rise sharply. This high temperature triggers a complex chain of chemical reactions within the battery. First, the electrolyte within the battery decomposes under the influence of high temperatures. Electrolytes are typically composed of organic solvents and lithium salts, and their decomposition products may include gases (such as carbon dioxide, carbon monoxide, and hydrogen), solid particles, and corrosive chemicals. This electrolyte decomposition not only alters the chemical balance within the battery, leading to a decrease in electrochemical performance, but also generates gases that rapidly increase internal pressure, increasing the risk of bulging, deformation, and even rupture.

[0038] At the same time, the battery's positive and negative electrode materials also decompose under high temperature conditions. Positive electrode materials (such as lithium cobalt oxide, lithium manganese oxide, and lithium iron phosphate) and negative electrode materials (such as graphite and silicon-based materials) undergo structural phase transitions and redox reactions at high temperatures, leading to the destruction of the electrode materials' crystal structure and loss of active substances. This, in turn, irreversibly reduces the battery's capacity and deteriorates its charge and discharge performance.

[0039] As the above-mentioned chain chemical reaction continues, the temperature inside the battery will continue to rise, which may eventually trigger thermal runaway of the battery. Thermal runaway is an extremely destructive battery failure mode, which is manifested by a sharp rise in temperature and pressure inside the battery. The battery casing may rupture, burn, or even explode. The thermal runaway of the battery will not only cause the battery itself to be completely damaged and lose its use value, but the flames, high temperatures generated by its combustion, and the shock waves and fragments generated by the explosion may also cause serious damage to the surrounding environmental facilities, posing a direct threat to the life safety of operators and surrounding personnel. This embodiment relates to a cover assembly, In order to effectively prevent the welding slag on the cover plate 1 from puncturing the diaphragm, this embodiment relates to a cover plate assembly, which can improve the safety and reliability of power battery applications by improving the structure of the cover plate 1 and the lower plastic 2.

[0040] In order to better understand the cover assembly of this embodiment, the structure of the power battery is briefly described here first. Figures 1 to 5 As shown, generally speaking, a power battery includes a battery housing and an electrode group 3 located in the battery housing, and the electrode group 3 includes a positive electrode sheet, a negative electrode sheet, and a separator sandwiched between the positive electrode sheet and the negative electrode sheet.

[0041] The battery case generally includes a case body, which has a receiving cavity with an opening on one side. The cover assembly seals one side of the opening to form a closed receiving cavity, and the aforementioned electrode group 3 is located in the receiving cavity.

[0042] An exemplary structure of the cover plate assembly of this embodiment is as follows: Figures 9 and 10 and Figure 12 As shown, the cover plate assembly includes a cover plate 1 , a pole 5 passing through the cover plate 1 , and a lower plastic 2 provided on one side of the cover plate 1 and capable of insulating the cover plate 1 and the pole 5 .

[0043] The cover plate 1 is in an elongated shape and an explosion-proof valve 7 can be installed on the cover plate 1 ; the lower plastic 2 includes a lower plastic body 201 arranged along the cover plate 1 , and a protective portion 202 connected to the lower plastic body 201 in the width direction of the lower plastic body 201 .

[0044] In a preferred embodiment, the protective portion 202 extends along the length direction of the lower plastic body 201, a buckle 2011 is provided on the protective portion 202, and a through hole 2014 is provided on the lower plastic body 201. The snap-fit ​​portion of the buckle 2011 can pass through the through hole 2014 and be snap-connected to the lower plastic body 201, so that the protective portion 202 is blocked on the side of the lower plastic body 201 facing away from the cover plate 1.

[0045] Each protective portion 202 is snap-connected to the lower plastic body 201. Since the cover 1 is generally made of metal, the snap connection between the lower plastic 2 and the cover 1 allows the protective portion 202 to be securely positioned on the side of the lower plastic body 201 facing the electrode group 3. Snap-connection is a quick connection method that, compared to traditional threaded connections and welding, does not require complex tools or operating procedures.

[0046] By using a snap-fit ​​method, after the protective part 202, the lower plastic body 201, and the cover plate 1 are aligned, assembly can be completed with a light push or a press, which can greatly improve production efficiency. When the protective part 202 needs to be disassembled for maintenance or replacement, it is also only necessary to apply a certain external force to release the snap-fit ​​relationship, and the protective part 202 can be removed, which is convenient and quick. Because the snap-fit ​​operation is simple and easy to learn, and the skill requirements for the operator are relatively low, the company does not need to invest a lot of time and money in professional training for employees, which allows the company to arrange production personnel more flexibly and reduce labor costs. At the same time, the rapid assembly and disassembly process can also shorten the production cycle, improve equipment utilization, and thus further reduce production costs.

[0047] like Figure 10 and Figure 12 As shown, in an exemplary embodiment, two cavities 2023 are provided on the protective portion 202 , the two cavities 2023 correspond to the poles 5 on the cover plate 1 one by one, and each cavity 2023 is recessed toward the side away from the cover plate 11 .

[0048] It should be noted that since welding slag is easily generated at the welding location of the pole 5 and the pole ear 301, the cover assembly described in the present application is configured such that the lower plastic 2 includes a lower plastic body 201 and a protective portion 202, and the clip 2011 on the protective portion 202 passes through the lower plastic body 201 and is connected to the cover 1 by clipping. The reliability of the clip connection between the cover 1 and the protective portion 202 is high, so that the protective portion 202 can be firmly blocked on the side of the corresponding pole ear 301 facing away from the cover 1. This structure is applied to power batteries, which can better prevent the welding slag of the pole 5 and the pole ear 301 from piercing the diaphragm.

[0049] In one example, by Figure 3 Combine Figure 8As shown, both the lower plastic body 201 and the protective portion 202 are provided with an opening 2027 corresponding to the explosion-proof valve 7, and the protective portion 202 is provided with a cavity 2023 corresponding to the pole 5, and one side of the cavity 2023 is open, and the open side faces the lower plastic body 201.

[0050] Here, the opening 2027 corresponding to the explosion-proof valve 7 is conducive to improving the reliability of the application of the explosion-proof valve 7. The cavity 2023 provided can provide sufficient space to cover the welding part of the pole 5 and the tab 301, which can further prevent the diaphragm from being punctured, further reduce the risk of puncturing the diaphragm, and improve the safety and reliability of the power battery.

[0051] In a preferred embodiment, Figure 3 As shown, a third mounting hole 1013 for mounting an explosion-proof valve 7 is provided in the middle of the cover plate 1. The explosion-proof valve 7 is mounted at the third mounting hole 1013, and a protective film 8 is sealed at the third mounting hole 1013. The protective film 8 can be made of an existing waterproof and breathable film. The protective film 8 is placed on the outside of the explosion-proof valve 7, which can play a better waterproof and breathable role.

[0052] There is a single third mounting hole 1013 for mounting the explosion-proof valve 7, located in the middle of the cover plate 1. Mounting holes 101 are located on either side of the third mounting hole 1013, each of which is used to mount a terminal 5. Specifically, there are two mounting holes 101, each with a terminal 5 mounted therein. The two mounting holes 101 are located on either side of the third mounting hole 1013, and the lower plastic body 1 is provided with through-holes corresponding to the respective mounting holes 101.

[0053] In an exemplary embodiment, the lower plastic body 201 has multiple openings 2027 corresponding to the explosion-proof valve 7. For ease of description, the openings 2027 on the lower plastic body 201 are referred to as first openings 20271. It should be understood that the number of first openings 20271 is not limited herein, and may be three, five, or twelve, for example. The shape of the first openings 20271 is also not limited, and may be circular, square, triangular, or other irregular shapes.

[0054] The number of openings 2027 on the protective portion 202 corresponding to the explosion-proof valve 7 is four, and they are oval holes. For ease of description, the openings 2027 on the protective portion 202 are referred to as second openings 20272. It should be understood that the number of second openings 20272 can also be other values, such as one, three, five, etc., and the shape of the second openings 20272 can also be other shapes, such as circular, square, triangular, etc., or other irregular shapes.

[0055] In a preferred embodiment, the number of first openings 20271 is greater than the number of second openings 20272. For example, in this embodiment, the number of first openings 20271 is 12, and the number of second openings 20272 is 4, and the range of the opening area is close to the size of the explosion-proof valve 7, so that the area where the first openings 20271 are formed can ensure sufficient structural strength, can stably support the explosion-proof valve 7, and can improve the reliability of the installation and fixation of the explosion-proof valve 7.

[0056] Still refer to Figure 3 As shown, in one example, the area where the second opening 20272 is formed protrudes toward the side away from the cover plate 1, and the protruding height of the area where the second opening 20272 is formed is smaller than the protruding height of the middle area 2021 described below. With this arrangement, the middle area 202 presses against the pole group 3, thereby forming a primary buffering effect on the pole group 3, while the area where the second opening 20272 is formed can form a secondary buffering effect on the pole group 3 when the pole group 3 moves up and down. The combination of the two levels of buffering can better reduce the risk of the pole group 3 moving up and down in harsh environments, and can better reduce the risk of the pole ear 301 tearing and the risk of puncturing the diaphragm.

[0057] like Figure 3 and Figure 5 As shown, in some exemplary embodiments, the cover plate 1 is provided with a snap-fit ​​hole 102 , which is a blind hole. The snap-fit ​​portion of the buckle 2011 can pass through the through hole 2014 and be snapped into the snap-fit ​​hole 102 .

[0058] Here, the snap-fit ​​hole 102 on the cover plate 1 is set as a blind hole. There is no need to worry about electrolyte leakage at the snap-fit ​​hole 102, nor is there any need to worry about external impurities entering the power battery through the snap-fit ​​hole 102. This can better improve the safety and reliability of the cover plate assembly application. The buckle 2011 part will not be exposed, which can better ensure the appearance quality of the cover plate 1.

[0059] For example Figures 8 to 10 and Figure 12 As shown, there are ten clips 2011 on the protective portion 202. Each clip 2011 corresponds to the clip holes 102 on the cover 1. When the protective portion 202 is bent to one side of the lower plastic body 201, the corresponding clips 2011 and clip holes 102 snap together. For ease of description, a group of clips 2011 and clip holes 102 snap together is referred to as a group of snap structures.

[0060] In a preferred embodiment, continue Figures 8 to 10 and Figure 12As shown, five groups of clip structures are provided on both sides of each pole 5, and along the length direction of the cover plate 1 body, there are two groups of clip structures near the outer side of the cover plate 1, and three groups of clip structures near the middle of the cover plate 1. The clip structures on both sides of each pole 5 are arranged at intervals along the width direction of the cover plate 1, which is conducive to the protective part 202 being firmly clipped and connected to the cover plate 1, and is conducive to ensuring the fit between the protective part 202 and the lower plastic body 201 after clipping, and can play a better fixing and shaping role on the pole ear 301.

[0061] It should be understood that the number of the locking structures between each protective portion 202 and the lower plastic body 201 can be not only ten groups, but also other numbers, such as two groups, three groups, five groups, etc.

[0062] The buckle 2011 is positioned on the protective portion 202, and the engaging hole 102 is provided on the cover 1. When the buckle 2011 is engaged with the engaging hole 102, the two form a tight fit. The rational design of the buckle 2011 and engaging hole 102 provides sufficient friction and mechanical locking force, ensuring that the cover 1 and the protective portion 202 will not easily separate even under normal external forces.

[0063] Reference Figure 12 and Figure 13 As shown, in order to improve the snapping effect, in some exemplary embodiments, the buckle 2011 includes a snapping portion, and a connecting portion connecting the snapping portion to the protective portion 202, and the snapping hole 102 includes a first snapping hole 1021 and a second snapping hole 1022 that are connected to each other, the aperture of the first snapping hole 1021 is smaller than the aperture of the second snapping hole 1022, and the connecting portion is arranged through the first snapping hole 1021 and the through hole 2014, and the snapping portion is snapped into the second snapping hole 1022.

[0064] The snap 2011 includes a snapping portion and a connecting portion, and the snapping hole 102 includes a first snapping hole 1021 and a second snapping hole 1022 with different apertures. When the connecting portion passes through the first snapping hole 1021 and the through hole 2014, the snapping portion is clamped in the second snapping hole 1022, so that the snap 2011 can be firmly fixed in the snapping hole 102, which is beneficial to improving the reliability of the snap connection between the cover 1 and the protective part 202.

[0065] In some exemplary embodiments, the buckle 2011 includes a plurality of sub-buckles 20111 arranged at circumferential intervals along the snap-fit ​​hole 102, each sub-buckle 20111 having a connecting block 20113 connected to the protective part 202, and a snap-fit ​​block 20112 protruding radially toward the outside of the connecting block 20113 of the buckle 2011. The buckle 2011 is clamped on the cover plate 1 through the snap-fit ​​block 20112, and each connecting block 20113 together constitutes the aforementioned connecting part, and each snap-fit ​​block 20112 together constitutes the aforementioned snap-fit ​​part.

[0066] The buckle 2011 includes multiple sub-buckles 20111, each sub-buckle 20111 includes a snap-on block 20112 and a connecting block 20113, multiple snap-on blocks 20112 together constitute a snap-on portion, and multiple connecting blocks 20113 together constitute a connecting portion. When the buckle 2011 is clamped into the clamping hole 102, multiple snap-on blocks 20112 are offset toward the center line of the buckle 2011 together, so that the clamping hole 102 can be smoothly clamped into the clamping hole 102, the clamping process is convenient, and after the clamping is completed, each snap-on block 20112 is reset under the action of its own connecting block 20113, so that the buckle 2011 can be firmly clamped into the clamping hole 102, and the reliability and stability of the clamping are high.

[0067] In one example, the cross-sections of the first engaging hole 1021 and the second engaging hole 1022 are both circular, and the cross-sections of the connecting portion and the engaging portion are also circular. In the above structure, the buckle 2011 includes a engaging portion and a connecting portion, and the engaging hole 102 includes a first engaging hole 1021 and a second engaging hole 1022 of different apertures. The connecting portion is embedded in the first engaging hole 1021, and the engaging portion is locked in the second engaging hole 1022. This allows the buckle 2011 to be firmly fixed in the engaging hole 102, thereby improving the reliability of the engaging connection between the cover 1 and the protective portion 202.

[0068] It should be noted that when the buckle 2011 is engaged with the engaging hole 102, the center line of the buckle 2011 is collinear with the axial center line of the engaging hole 102. Figure 8 As shown, there are two sub-buckles 20111 , and the cross section of the snap-fitting portion of each sub-buckle 20111 is sector-shaped with a central angle of 180°, and the cross section of the connecting portion of each sub-buckle 20111 is also sector-shaped with a central angle of 180°.

[0069] It is worth mentioning that in order to facilitate the buckle 2011 to be placed in the snap hole 102, in a preferred embodiment, the end of the snap part that is first inserted into the snap hole 102 is provided with a guide portion, which is used to guide the buckle 2011 to be placed in the snap hole 102.

[0070] In a specific implementation, the guide portion can be a chamfered edge provided on the edge of the engaging portion to facilitate smooth insertion of the buckle 2011 into the engaging hole 102. For example, in this embodiment, the edge of each sub-buckle 20111 away from the protective portion 202 is chamfered to facilitate increasing the speed at which the buckle 2011 is inserted into the engaging hole 102.

[0071] Continue to refer to Figure 3 and Figure 5As shown, in some exemplary embodiments, the lower plastic body 201 has a first protrusion 2015 protruding toward one side of the protective portion 202 , and the through hole 2014 is provided at the first protrusion 2015 and passes through the lower plastic body 201 .

[0072] Here, by providing a first protrusion 2015 on the protective part 202 and providing a through hole 2014 at the first protrusion 2015 and passing through the protective part 202, the thickness of the through hole 2014 can be increased. When the cover plate 1 and the protective part 202 are snap-connected, the hole wall of the through hole 2014 can play a certain fixing role on the snap 2011 in the radial direction of the snap 2011, which can better prevent the snap 2011 from shaking and prevent the snap 2011 from falling out of the snap hole 102, thereby further improving the stability and reliability of the snap connection between the cover plate 1 and the protective part 202.

[0073] Continue to refer to Figure 5 As shown, a guide portion is provided at one end of the through hole 2014 facing the protective portion 202 , and the guide portion is rounded or chamfered, so that the buckle 2011 can pass through the through hole 2014 smoothly and quickly, thereby facilitating the snapping portion of the buckle 2011 to be snapped into the snapping hole 102 .

[0074] It should be noted that the pole 5 is insulated from the cover 1. The specific structure of the pole 5 and its mounting on the cover 1 are described below. The structure of the lower plastic body 201 can be similar to existing lower plastic structures, serving to insulate the pole 5 from the cover 1. The connection between the lower plastic body 201 and the cover 1 can also be similar to existing techniques.

[0075] Specifically, generally, there are two poles 5 on the cover plate 1, and the pole lugs 301 on the pole group 3 are respectively welded to the corresponding poles 5, so two cavities 2023 need to be provided. Figure 8 、 Figure 9 As shown, the lower plastic body 201 is connected to the cover 1 , and the shape of the lower plastic body 201 is substantially the same as that of the cover 1 .

[0076] In some exemplary embodiments, the protective portion 202 has a central region 2021 corresponding to the pole 5 and an edge region 2022 surrounding the central region 2021 ; the cavity 2023 is formed by the central region 2021 being recessed toward a side away from the lower plastic body 201 , and the central region 2021 is used to press against the pole group 3 .

[0077] It should be understood that when actually forming the cavity 2023, the cavity 2023 can be formed by removing material from the middle area 2021. In this way, when the depth of the cavity 2023 is large, the thickness of the protective part 202 is large, and more material is used during production.

[0078] For ease of understanding, refer to Figures 8 to 10 As shown, the middle portion of the protective portion 202 corresponding to the pole 5 is referred to as the middle region 2021, and the edge of the protective portion 202 is referred to as the edge region 2022. In this embodiment, there are two middle regions 2021, which are spaced apart along the length of the cover plate 1, and the edges of the two middle regions 2021 are connected together to form an edge region 2022.

[0079] In some of the exemplary embodiments, reference is made to Figure 10 and Figure 12 As shown, each central region 2021 is recessed toward the side away from the cover plate 1 to form a cavity 2023. During processing, the central region 2021 and the edge region 2022 can have the same thickness, allowing the cavity 2023 to be formed even with materials having a smaller thickness. This structure is simple, easy to process, and uses less material. When this cover plate assembly is used in a power battery, the central region 2021 can abut against the electrode group 3 within the power battery, thereby effectively attenuating vibrations of the electrode group 3.

[0080] In some exemplary embodiments, the central region 2021 and the edge region 2022 are connected by connecting ribs 2025 , and a plurality of connecting ribs 2025 are arranged at intervals around the central region 2021 .

[0081] Reference Figure 10 and Figure 12 As shown, in some exemplary embodiments, the central region 2021 and the edge region 2022 are connected by connecting ribs 2025, connecting ribs 2025 are provided on both sides of the central region 2021, and a plurality of connecting ribs 2025 on each side are arranged in sequence and spaced apart.

[0082] For example Figure 10 In the example shown, connecting ribs 2025 are provided on both sides of the middle area 2021 along the length direction of the cover plate 1, there are four connecting ribs 2025 on each side, and the four connecting ribs 2025 on each side are arranged in sequence along the width direction of the cover plate 1.

[0083] The spaces between any adjacent connecting ribs 2025 on each side allow for the passage of electrolyte. Along the width of the cover plate 1, strip holes are provided on both sides of the central region 2021. Each strip hole extends along the length of the cover plate 1, and the length of each strip hole is greater than the length of the cavity 2023 along the length of the cover plate 1. This ensures that the central region 2021 is connected only by the connecting ribs 2025 on both sides along the length.

[0084] For example Figure 4 、 Figure 5 and Figure 7 As shown in , after the cover plate assembly is assembled on the battery housing, the middle region 2021 and the electrode group 3 abut against each other. Thus, when the electrode group 3 shakes, the middle region 2021 can limit the position of the electrode group 3, thereby effectively attenuating the vibration of the electrode group 3. In actual layout, a certain gap between the middle region 2021 and the electrode group 3 is also acceptable.

[0085] In another example, a plurality of connecting ribs 2025 are provided around the central region 2021, and the plurality of connecting ribs 2025 are spaced apart around the central region 2021. Specifically, along the length direction of the cover plate 1, the connecting ribs 2025 on both sides of the central region 2021 are consistent with those described above. In addition, along the width direction of the cover plate 1, connecting ribs 2025 are also provided on both sides of the central region 2021, and the connecting ribs 2025 on both sides are spaced apart along the length direction of the cover plate 1.

[0086] It should be noted that the number of connecting ribs 2025 on each side can be arranged according to actual needs and is not limited to the four shown in the figure. For example, it can be one, three, or six. In the above structure, the central region 2021 and the edge region 2022 are connected by connecting ribs 2025. Spaces are provided between adjacent connecting ribs 2025 to allow electrolyte to flow through the spaces. This connection method also facilitates vibration of the central region 2021 and reduces material consumption, thereby saving costs.

[0087] In some exemplary embodiments, the protective portion 202 is connected to the lower plastic body 201 through the bending portion 203, so that the protective portion 202 can be bent relative to the lower plastic body 201 through the bending portion 203, which makes it easy to ensure the fit between the protective portion 202 and the lower plastic body 201, and the protective portion 202 after being bent relative to the lower plastic body 201 is snap-connected to the lower plastic body 201.

[0088] In order to better understand the assembly process of the cover assembly of this embodiment, for example Figure 8 As shown, the pole lug 301 of the pole group 3 is welded to the pole post 5, and the lower plastic body 201 is connected to the cover 1. This is a schematic diagram of the structure before the protective part 202 is bent. Figure 9 1 is a schematic structural diagram showing that the protection portion 202 is bent to one side of the lower plastic body 201 and blocks the side of the corresponding tab 301 facing away from the cover plate 1 .

[0089] like Figure 10As shown, in some exemplary embodiments, the protective portion 202 is connected to the lower plastic body 201 via a bent portion 203. Along the length of the cover 1, the bent portion 203 is smaller than the protective portion 202. For example, in one embodiment, there are two bent portions 203, each extending along the length of the cover 1, and the two bent portions 203 are spaced apart along the length of the cover 1.

[0090] In addition, each protective portion 202 is connected to the lower plastic body 201 through a bending portion 203, and the size of the bending portion 203 in the length direction of the cover plate 1 is limited to be smaller than the size of the protective portion 202. On the one hand, this is conducive to the smooth bending of the protective portion 202 relative to the lower plastic body 201. On the other hand, the size of the bending portion 203 in the length direction of the cover plate 1 can also save material usage to a certain extent, which further helps to save costs.

[0091] In some exemplary embodiments, the protective portion 202, the bent portion 203 and the lower plastic body 201 are integrally formed by an injection molding process, which is convenient for processing. The one-piece lower plastic 2 is also convenient to assemble and use during application, which can reduce the number of parts and facilitate management. At the same time, the lower plastic 2 processed by the injection molding process, in addition to having good insulation and protection properties, is not easily punctured by the welding slag of the pole 5 and the pole ear 301, thereby effectively reducing the risk of the welding slag puncturing the diaphragm.

[0092] In some exemplary embodiments, the bent portion 203 is provided with a glue reducing groove 2031, such as Figure 10 and Figure 11 As shown, the bent portion 203 extends along the length of the cover plate 1, and the adhesive reduction groove 2031 is provided on one side of the bent portion 203 and extends along the extension direction of the bent portion 203, thereby facilitating smooth bending of the bent portion. It should be understood that, in addition to this, the adhesive reduction groove 2031 can be provided on both sides of the bent portion 203, or it is also possible to not provide the adhesive reduction groove 2031. Here, the adhesive reduction groove 2031 provided on the bent portion 203 is convenient to manufacture and facilitates smooth bending of the bent portion.

[0093] In some exemplary embodiments, a through hole is provided on the bending portion 203. Here, the through hole provided on the bending portion 203 is easy to process and facilitates smooth bending of the bending portion. In this embodiment, there is no specific limitation on the number of through holes.

[0094] Reference Figures 4 to 7 As shown, in some exemplary embodiments, the cover plate 1 is provided with a mounting hole 101 for the pole 5 to pass through, and a sealing ring 4 is provided between the pole 5 and the cover plate 1 to seal the gap therebetween.

[0095] The pole 5 includes a cylindrical pole body 501, and a first boss 502 and a second boss 503 arranged on the outer periphery of the pole body 501; in a direction orthogonal to the axial direction of the pole body 501, the first boss 502 and the second boss 503 both protrude outward from the pole body 501, and the outer diameter of the first boss 502 and the outer diameter of the second boss 503 are both larger than the aperture of the mounting hole 101.

[0096] The terminal 5 comprises a terminal body 501, a first boss 502, and a second boss 503. The outer diameters of the first boss 502 and the second boss 503 are both larger than the diameter of the mounting hole 101, allowing the terminal 5 to be securely mounted on the cover plate 1, thereby improving the installability and reliability of the power battery. The sealing ring 4 effectively seals the gap between the cover plate 1 and the terminal 5, preventing electrolyte leakage and external impurities from entering the power battery through the mounting hole, further improving the installability and reliability of the power battery.

[0097] It should be noted that, referring to Figure 5 As shown, the sealing ring 4 with an L-shaped cross section can be first inserted into the mounting hole 101 from bottom to top. When the first boss 502 is initially processed, it can extend along the axial direction of the pole body 501. The pole 5 is then inserted from bottom to top through the sealing ring 4 and the mounting hole 101. The upper plastic 6 is then fitted onto the pole body 501, with the upper plastic 6 partially inserted into the gap between the pole 5 and the cover 1. The first boss 502 is then bent until it presses the upper plastic 6, completing the installation process of the pole 5.

[0098] In some exemplary embodiments, each mounting hole 101 includes a first mounting hole 1011 and a second mounting hole 1012 that are connected; the aperture of the first mounting hole 1011 is smaller than the aperture of the second mounting hole 1012, and the second mounting hole 1012 is located on the side of the cover 1 facing the lower plastic 2; the sealing ring 4 is installed at the first mounting hole 1011, and the lower plastic body 201 is provided with a second protrusion 2016 embedded in the second mounting hole 1012, and the second protrusion 2016 surrounds the periphery of the pole 5.

[0099] Here, the mounting holes include a first mounting hole 1011 and a second mounting hole 1012 that are connected. The diameter of the first mounting hole 1011 is defined to be smaller than the diameter of the second mounting hole 1012. The second mounting hole 1012 is located on the side of the cover plate 1 facing the lower plastic 2 relative to the first mounting hole 1011. The sealing ring 4 is installed at the first mounting hole 1011 to form a seal, and the second protrusion 2016 on the lower plastic body 201 is embedded in the second mounting hole 1012 to form a second seal. The two seals are formed, and the two seals are stepped, which can effectively improve the sealing effect between the cover plate 1 and the pole 5.

[0100] Continue to refer to Figures 4 to 7 As shown, in one example, a ring-shaped third protrusion 103 is provided on the cover plate 1, and the periphery of each pole 5 is surrounded by the third protrusion 103, and a groove for embedding the third protrusion 103 is provided on the lower plastic body 201. By embedding the third protrusion 103 in the groove, the sealing performance at the mounting hole 101 can be further improved.

[0101] Finally, it should be noted that the material of the lower plastic 2 can refer to existing literature. For example, it can be made of polypropylene (PP). Because polypropylene has excellent electrical insulation and impact resistance, it not only effectively insulates the cover 1 from the pole 5, but also utilizes its excellent elastic properties to improve the vibration attenuation effect on the pole group 3.

[0102] The cover plate assembly of this embodiment is configured such that the lower plastic 2 includes a lower plastic body 201 and a protective portion 202, and the lower plastic body 201 is connected to the cover plate 1 by being snap-connected, and is blocked on the side of the corresponding pole tab 301 facing away from the cover plate 1. This can effectively prevent welding slag formed by welding the pole tab 301 to the cover plate 1 from piercing the diaphragm in the pole group 3. When applied to power batteries, it can improve the safety and reliability of the power batteries.

[0103] At the same time, the present application also relates to a power battery, which is provided with the cover plate assembly as described above.

[0104] Meanwhile, this embodiment also relates to an electric device, wherein the power battery of the electric device is provided with the above cover assembly. The electric device may be, for example, an existing vehicle.

[0105] In this embodiment, by applying the aforementioned cover plate assembly to the power battery, the safety and reliability of the power battery can be improved, thereby improving the safety and reliability of electrical equipment.

[0106] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A cover plate assembly, characterized in that: It includes a cover plate, a pole arranged through the cover plate, and a lower plastic provided on one side of the cover plate and capable of insulating the cover plate and the pole; The cover plate is in an elongated strip shape, and an explosion-proof valve can be installed on the cover plate; The lower plastic comprises a lower plastic body arranged in accordance with the cover plate, and a protective portion connected to the lower plastic body in the width direction of the lower plastic body; The protective portion extends along the length direction of the lower plastic body, and is provided with a buckle on the protective portion. The lower plastic body is provided with a through hole, and the clamping portion of the buckle can pass through the through hole and be clamped and connected to the lower plastic body, so that the protective portion is blocked on the side of the lower plastic body facing away from the cover plate; The lower plastic body and the protective part are both provided with openings corresponding to the explosion-proof valve. The protective part is provided with a cavity corresponding to the pole. One side of the cavity is open, and the open side faces the lower plastic body.

2. The cover assembly according to claim 1, characterized in that: The cover plate is provided with a snap-fitting hole, which is a blind hole. The snap-fitting portion of the buckle can pass through the through hole and be snapped into the snap-fitting hole.

3. The cover assembly according to claim 1, characterized in that: The lower plastic body has a first protrusion protruding toward one side of the protective portion. The through hole is provided at the first protrusion and passes through the lower plastic body.

4. The cover assembly according to claim 1, characterized in that: The protection portion comprises a middle region corresponding to the pole and an edge region surrounding the middle region; The cavity is formed by the middle region being recessed toward a side away from the lower plastic body, and the middle region is used for pressing against the electrode group.

5. The cover assembly according to claim 4, characterized in that: The middle area and the edge area are connected by connecting ribs, and the connecting ribs are multiple and spaced around the middle area.

6. The cover assembly according to claim 1, characterized in that: The protective portion is connected to the lower plastic body via a bent portion, and the protective portion, the bent portion and the lower plastic body are integrally formed through an injection molding process.

7. The cover assembly according to claim 6, characterized in that: The bent portion is provided with a glue reducing groove; and / or, The bent portion is provided with a through hole.

8. The cover plate assembly according to any one of claims 1 to 7, characterized in that: The cover plate is provided with a mounting hole for the pole to pass through, and a sealing ring is provided between the pole and the cover plate to seal the gap therebetween; The pole comprises a cylindrical pole body, and a first boss and a second boss provided on the outer periphery of the pole body; In a direction orthogonal to the axial direction of the pole body, the first boss and the second boss both protrude outward from the pole body, and the outer diameters of the first boss and the second boss are both larger than the diameter of the mounting hole.

9. The cover assembly according to claim 8, characterized in that: The mounting hole comprises a first mounting hole and a second mounting hole that are connected; The diameter of the first mounting hole is smaller than that of the second mounting hole, and the second mounting hole is located on a side of the cover plate facing the lower plastic; The sealing ring is installed at the first installation hole. The lower plastic body is provided with a second protrusion embedded in the second installation hole. The second protrusion surrounds the periphery of the pole.

10. A power battery, characterized in that: The housing of the power battery is provided with the cover assembly according to any one of claims 1 to 9.

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