Cover assembly and power battery

Abstract

The application provides a cover assembly and a power battery. The cover assembly comprises a cover provided with an explosion-proof valve, a pole penetrating through the cover, and an insulation structure arranged on one side of the cover and capable of insulating the cover and the pole; the cover is in a strip shape, the insulation structure comprises a body part arranged along the cover and a shielding part connected with the body part in the width direction of the body part; the shielding part can be bent to one side in the thickness direction of the body part, and the bent shielding part extends in the length direction of the body part; the bent shielding part can be connected with the body part and arranged on the side of the body part away from the cover; the shielding part is provided with a through hole corresponding to the explosion-proof valve and a groove corresponding to the pole, and the groove is recessed away from the body part. The cover assembly can reduce the risk of the diaphragm being punctured, and is beneficial to improving the use safety of the power battery.

Description

Technical Field

[0001] This application relates to the field of power battery technology, and in particular to a cover plate assembly and a power battery. Background Technology

[0002] In a power battery, the electrode assembly generates or stores electrical energy through an internal electrochemical reaction. The tabs collect current from the positive and negative plates of the electrode assembly and connect to an external circuit through the terminals.

[0003] In this battery assembly, a separator is installed between the positive and negative electrode plates. This separator is a crucial component for isolating the positive and negative electrodes. Conventional terminals and tabs are connected by welding. During welding, weld slag may form and fall into the separator. Because weld slag has sharp edges, if it punctures the separator, the positive and negative electrodes inside the battery will come into direct contact, creating a short circuit. The high temperature generated by this short circuit may trigger a chain reaction inside the battery, potentially leading to thermal runaway. This poses a threat to the surrounding environment and personnel safety, and is detrimental to the safety of the power battery. Utility Model Content

[0004] In view of this, this application aims to propose a cover assembly to improve the safety of power battery use.

[0005] To achieve the above objectives, the technical solution of this application is implemented as follows: A cover plate assembly includes a cover plate with an explosion-proof valve, an electrode post passing through the cover plate, and an insulating structure disposed on one side of the cover plate and capable of insulating the cover plate and the electrode post. The cover plate is elongated, and the insulating structure includes a body portion conforming to the shape of the cover plate, and a shielding portion connected to the body portion in the width direction of the body portion; The shielding portion can be bent to one side of the thickness direction of the main body portion, and the bent shielding portion extends along the length direction of the main body portion. The bent shielding portion can be connected to the main body portion and block the side of the main body portion facing away from the cover plate. The shielding portion is provided with a through hole corresponding to the explosion-proof valve and a groove corresponding to the pole post, and the groove is recessed towards the side away from the main body portion.

[0006] Furthermore, the shielding portion is connected to the main body portion through a thinned connecting portion, and the shielding portion, the connecting portion, and the main body portion are integrally formed by injection molding.

[0007] Furthermore, the shielding portion has a central region corresponding to the pole post and an edge region surrounding the central region; The groove is formed by recessing the central region toward the side away from the body portion.

[0008] Furthermore, the central region and the edge region are connected by connecting ribs, which are multiple ribs arranged at intervals around the central region.

[0009] Furthermore, the length L of the connecting rib is between 3.0mm and 10mm, and the width W of the connecting rib is between 0.5mm and 5mm.

[0010] Furthermore, the effective depth h of the groove is between 0.3mm and 8mm, and the total depth H of the groove is between 1.2mm and 6.5mm.

[0011] Furthermore, the blocking portion is connected to the main body portion by a snap-fit ​​part, and the snap-fit ​​part includes a buckle provided on the main body portion and a snap-fit ​​hole provided on the blocking portion, the buckle being able to be snapped into the snap-fit ​​hole.

[0012] Furthermore, the blocking portion has a protrusion that protrudes toward one side of the main body portion, and the snap-fit ​​hole is provided at the protrusion and penetrates the blocking portion; After being snapped in, the blocking portion abuts against the main body portion via the protrusion.

[0013] Furthermore, the buckle includes a plurality of sub-buckles spaced circumferentially along the snap-fit ​​hole, each sub-buckle having a connecting block connected to the main body portion, and a snap-fit ​​block protruding radially outward from the connecting block. The buckle is engaged with the blocking portion via the snap-fit ​​block.

[0014] Furthermore, the snap-fit ​​hole includes a first snap-fit ​​hole and a second snap-fit ​​hole that are connected to each other, wherein the diameter of the first snap-fit ​​hole is smaller than the diameter of the second snap-fit ​​hole; The connecting block is inserted into the first card hole, and the snap-fit ​​block is snapped into the second card hole.

[0015] Compared with the prior art, this application has the following advantages: (1) The cover plate assembly described in this application, by setting an insulating structure, places the shielding part on the side of the main body part facing away from the cover plate, and a space for accommodating the electrode tab can be formed between the shielding part and the main body part. The electrode post passing through the cover plate can be welded to the electrode tab. The welding slag generated by welding will be blocked by the shielding part. At the same time, the groove set on the shielding part corresponding to the electrode post can accommodate the welding slag generated by welding, making it difficult for the welding slag to enter the electrode group, reducing the risk of the separator being punctured. Using the cover plate assembly on the power battery is beneficial to improving the safety of the power battery.

[0016] (2) The shielding part is connected to the main body part through a thinned connecting part, which can reduce the force required for the shielding part to bend, which is conducive to the smooth bending of the shielding part; at the same time, the shielding part, the connecting part and the main body part are injection molded as one piece, which is convenient to process and easy to assemble.

[0017] (3) A central region is set, and a cavity is formed by recessing the central region toward the side away from the cover plate. The structure is simple, easy to process, and uses less material. When the cover plate assembly is applied to the power battery, the central region can limit the position of the electrode group in the power battery, which can help to attenuate the vibration of the electrode group.

[0018] (4) Multiple intermittently arranged connecting ribs can ensure the connection strength while forming through holes between each connecting rib for the electrolyte to pass through. In addition, it can also reduce the weight of the entire shielding part to a certain extent, optimize the product structure, and reduce the production materials. The intermittent arrangement of the connecting ribs allows each part to be evenly stressed during the bending process of the shielding part, reducing the risk of damage caused by stress concentration and improving the durability of the shielding part.

[0019] (5) The length L of the connecting rib is between 3.0mm and 10mm, and the width W is between 0.5mm and 5mm. This size range has been optimized to ensure that the connecting rib has sufficient strength to connect the middle and edge areas, and that the size is not too large, which would increase the weight of the entire shielding part too much or occupy too much space. While ensuring structural strength, the product is lightweight and miniaturized. The effective depth h of the groove is between 0.3mm and 8mm, which can ensure that the groove can accommodate welding slag without excessively occupying the internal space of the power battery. The total depth H of the groove is between 1.2mm and 6.5mm, which can ensure that the through holes between the connecting ribs are sufficient for electrolyte flow without excessively occupying the internal space of the power battery.

[0020] (6) The shielding part and the main body are connected by a snap-fit ​​part. The snap-fit ​​method is simple and convenient to operate, and is easy to install and disassemble during the production process. Compared with other connection methods, the snap-fit ​​part does not require additional connection tools or connectors, which reduces production costs. Moreover, the snap-fit ​​structure is simple and reliable, and can provide sufficient connection strength to ensure that the shielding part is firmly connected to the main body after bending, and maintain the effective shielding of the electrode tab and electrode post welding parts by the shielding part.

[0021] (7) A protrusion is provided in the shielding part, and the snap-fit ​​hole is set at the protrusion and penetrates the shielding part. This provides sufficient depth for the snap-fit, improving the reliability and stability of the connection. At the same time, after the shielding part and the main body are snapped together, the protrusion can also play a limiting role, limiting the minimum distance between the shielding part and the main body.

[0022] (8) The buckle includes multiple sub-buckles, each of which includes a snap-fit ​​block and a connecting block. When the buckle is snapped into the snap-fit ​​hole, the multiple snap-fit ​​blocks shift together toward the center line of the buckle, so that the snap-fit ​​blocks can be snapped into the snap-fit ​​hole smoothly. The snap-fit ​​process is convenient. After the snap-fit ​​is completed, each snap-fit ​​block is reset under the action of its respective connecting block, so that the buckle can be firmly snapped into the snap-fit ​​hole. The reliability and stability of the snap-fit ​​are high.

[0023] (9) The connecting block is inserted into the first card hole, and the snap-fit ​​block is snapped into the second card hole. This snap-fit ​​hole design forms a stepped snap-fit ​​structure. The first card hole limits the connecting block, and the second card hole limits the snap-fit ​​block, so that a strong snap-fit ​​structure is formed between the buckle and the snap-fit ​​hole. The snap-fit ​​block is located in the second card hole and is not easily affected by external collisions. It can be kept relatively stably in the second card hole.

[0024] Another objective of this application is to provide a power battery in which the aforementioned cover assembly is provided on the casing of the power battery.

[0025] The power battery described in this application, by providing the aforementioned cover assembly on the casing, allows the shielding portion of the cover assembly to be positioned on the side of the main body facing away from the cover, thus forming a space between the shielding portion and the main body to accommodate the electrode tabs. The electrode post passing through the cover can be welded to the electrode tabs, and the welding slag produced during welding is blocked by the shielding portion. At the same time, the groove on the shielding portion corresponding to the electrode post can accommodate the welding slag produced during welding, making it difficult for the welding slag to enter the electrode assembly, reducing the risk of the separator being punctured, and improving the safety of the power battery in use. Attached Figure Description

[0026] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is an exemplary structural diagram of the cover plate assembly described in the embodiments of this application in an application state; Figure 2 for Figure 1 Top view; Figure 3 for Figure 2 Sectional view at point AA; Figure 4 for Figure 3A magnified view of part D in the middle; Figure 5 for Figure 2 Sectional view at point BB; Figure 6 for Figure 5 A magnified view of part E in the middle; Figure 7 for Figure 2 Sectional view at CC; Figure 8 for Figure 7 A magnified view of part F in the middle; Figure 9 This is a schematic diagram of an exemplary insulating structure according to an embodiment of this application; Figure 10 for Figure 9 A magnified view of part G in the middle; Figure 11 for Figure 9 Another perspective; Figure 12 for Figure 11 A magnified view of part I in the middle; Figure 13 for Figure 9 Another perspective; Figure 14 This is an exemplary structural diagram of the cover plate assembly and pole group assembly according to an embodiment of this application; Figure 15 for Figure 13 A schematic diagram of the structure in which the central protective section is bent to one side of the main structure; Explanation of reference numerals in the attached figures: 1. Cover plate; 101. Explosion-proof valve; 2. Pole post; 3. Insulation structure; 301. Body part; 3011. First mounting hole; 3012. Second mounting hole; 302. Covering part; 3021. Through hole; 3022. Groove; 3023. Central area; 3024. Edge area; 3025. Connecting rib; 3026. Snap-fit ​​hole; 30261. First snap-fit ​​hole; 30262. Second snap-fit ​​hole; 3027. Protrusion; 3028. Strip hole; 303. Connecting part; 3031. Reducing groove; 304. Buckle; 3041. Separate buckle; 30411. Connecting block; 30412. Snap-fit ​​block; 4. Pole group; 401. Extreme Ear. Detailed Implementation

[0027] To make the technical solution and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0029] Furthermore, it should be noted that in the description of this application, if terms such as "upper," "lower," "inner," or "outer" appear, indicating orientation or positional relationship, these are based on the orientation or positional relationship shown in the accompanying drawings and 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. In addition, if terms such as "first" or "second" appear, they are also used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0030] Furthermore, in the description of this application, unless otherwise expressly defined, the terms "installation," "connection," "joining," and "connector" 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 mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application in light of the specific circumstances.

[0031] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0032] The present application will now be described in detail through exemplary embodiments. However, it should be understood that, without further description, elements, structures, and features in one embodiment may be advantageously incorporated into other embodiments.

[0033] An embodiment of the first aspect of this application provides a cover assembly to reduce the short-circuit risk of a power battery and improve its safety.

[0034] In existing technologies, the welding process between the tabs and the cover plate plays a crucial role in the battery manufacturing process, and is one of the core links that determines the final quality of the battery. The welding quality of this process is closely and directly related to the safety and electrochemical performance of the battery, and its quality plays a decisive role in whether the battery can operate stably and safely in complex and changing usage environments.

[0035] However, during the welding process of the electrode tab and the cover plate, welding slag is easily generated at the welding site due to factors such as slight fluctuations in welding process parameters (e.g., welding current, welding time, welding pressure), precision deviations of welding equipment, and differences in the skill level of operators. The morphology, size, and distribution of these welding slags are uncertain, and they may exist in the welding area as tiny particles, flakes, or irregular shapes.

[0036] During subsequent assembly, transportation, or use of the battery, if it detaches or shifts due to factors such as minor internal vibrations, stress changes, or external impacts, welding slag is highly likely to cause physical puncture damage to the separator. Once the separator is punctured by welding slag, the isolation between the positive and negative electrodes maintained by the separator will be broken, and the positive and negative electrodes will directly make electrical contact, thus causing a short circuit fault.

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

[0038] At the same time, the positive and negative electrode materials of the battery will also decompose under high temperature conditions. Positive electrode materials (such as lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate, etc.) and negative electrode materials (such as graphite, silicon-based materials, etc.) will undergo structural phase transitions and redox reactions at high temperatures, which will lead to the destruction of the crystal structure of the electrode materials and the loss of active materials, thereby causing irreversible capacity decay and deterioration of charge and discharge performance.

[0039] As the aforementioned chain chemical reaction continues, the internal temperature of the battery will continue to rise, potentially leading to thermal runaway. Thermal runaway is a highly destructive battery failure mode, characterized by a rapid increase in internal temperature and pressure, which can cause the battery casing to rupture, burn, or even explode. Thermal runaway not only completely destroys the battery, rendering it unusable, but the flames, high temperatures from combustion, and the shockwaves and debris from an explosion can also cause severe damage to surrounding infrastructure and pose a direct threat to the lives of operators and those nearby.

[0040] In view of this, in order to overcome the shortcomings of the prior art, the cover plate assembly of this embodiment combines... Figures 1 to 9 In terms of overall design, it includes a cover plate 1 with an explosion-proof valve 101, an electrode post 2 passing through the cover plate 1, and an insulation structure 3 located on one side of the cover plate 1 and capable of insulating the cover plate 1 and the electrode post 2.

[0041] The cover plate 1 is elongated, and the insulating structure 3 includes a body portion 301 conforming to the shape of the cover plate 1, and a blocking portion 302 connected to the body portion 301 in the width direction. The blocking portion 302 can be bent to one side in the thickness direction of the body portion 301, and the bent blocking portion 302 extends along the length direction of the body portion 301. The bent blocking portion 302 can be connected to the body portion 301 and is positioned on the side of the body portion 301 facing away from the cover plate 1. The blocking portion 302 has a through hole 3021 corresponding to the explosion-proof valve 101 and a groove 3022 corresponding to the pole post 2, and the groove 3022 is recessed towards the side away from the body portion 301.

[0042] Therefore, by setting the insulating structure 3, the shielding part 302 is placed on the side of the main body part 301 facing away from the cover plate 1, and a space for accommodating the tab 401 can be formed between the shielding part 302 and the main body part 301. The electrode post 2 passing through the cover plate 1 can be welded to the tab 401. The welding slag produced by welding will be blocked by the shielding part 302. At the same time, the groove 3022 on the shielding part 302 corresponding to the electrode post 2 can accommodate the welding slag produced by welding, making it difficult for the welding slag to enter the electrode group 4, reducing the risk of the separator being punctured. Using the cover plate assembly on the power battery is beneficial to improving the safety of the power battery.

[0043] Based on the above overview, generally speaking, a power battery includes a battery casing and an electrode assembly 4 located within the battery casing. The electrode assembly 4 includes a positive electrode, a negative electrode, and a separator sandwiched between the positive and negative electrode. The battery casing generally includes a casing body with a receiving cavity open on one side. A cover assembly seals one side of the opening to form a sealed receiving cavity, and the aforementioned electrode assembly 4 is located within the receiving cavity.

[0044] It should be noted that the electrode post 2 and the cover plate 1 are insulated from each other. The specific structure of the electrode post 2 and the installation method of the electrode post 2 on the cover plate 1 shall refer to the existing structure. The structure of the body part 301 can refer to the existing lower plastic structure, which is used to insulate the electrode post 2 and the cover plate 1, and the connection method between the body part 301 and the cover plate 1 shall still refer to the existing technology.

[0045] Specifically, generally, there are two pole posts 2 on the cover plate 1, and the pole lugs 401 on the pole assembly 4 are welded to the corresponding pole posts 2. For example, as shown in Figures 1-2, the body part 301 is connected to the cover plate 1, and the shape of the body part 301 is roughly the same as that of the cover plate 1. The aforementioned pole posts 2 are installed on the body part 301. The body part 301 is provided with a first mounting hole 3011 for installing the explosion-proof valve 101, and a second mounting hole 3012 for installing the pole post 2. The second mounting hole 3012 is located on both sides of the first mounting hole 3011.

[0046] Combination Figure 9 , Figure 11 As shown, in some exemplary embodiments, the shielding portion 302 is connected to the body portion 301 via a thinned connecting portion 303, and the shielding portion 302, the connecting portion 303, and the body portion 301 are integrally formed by injection molding.

[0047] In this way, the shielding part 302 is connected to the main body part 301 through the thinned connecting part 303, which can reduce the force required for the shielding part 302 to bend, and facilitate the smooth bending of the shielding part 302. At the same time, the shielding part 302, the connecting part 303 and the main body part 301 are injection molded as a single piece, which is convenient to process and easy to assemble.

[0048] For example, refer to Figure 11 and Figure 12 As shown, for the specific thinning method of the connecting portion 303, a through-hole adhesive reduction groove 3031 can be provided on the connecting portion 303 along the length direction of the cover plate 1. The adhesive reduction groove 3031 is located on one side of the connecting portion 303, which facilitates the blocking of the bending of the portion 302. Of course, it is also possible to provide the adhesive reduction groove 3031 only on the other side of the connecting portion 303, or on both sides of the connecting portion 303.

[0049] See Figures 3 to 6 As shown, in some exemplary embodiments, the shielding portion 302 has a central region 3023 corresponding to the pole post 2, and an edge region 3024 surrounding the central region 3023. The groove 3022 is formed by recessing the central region 3023 toward the side away from the body portion 301.

[0050] As shown above, a central region 3023 is provided, and a cavity is formed by recessing the central region 3023 toward the side away from the cover plate 1. The structure is simple, easy to process, and uses less material. When this cover plate assembly is applied to the power battery, the central region 3023 can limit the position of the electrode group 4 in the power battery, which can help to dampen the vibration of the electrode group 4.

[0051] Preferably, the shielding portion 302 may have two central regions 3023, each of which has a groove 3022, and each groove 3022 corresponds to a pole post 2. The position where the through hole 3021 is located in the center of the shielding portion 302 may be recessed in the direction away from the cover plate 1 to provide installation space for the explosion-proof valve 101.

[0052] Based on the fact that the occluded portion 302 has a central region 3023 and an edge region 3024, referring to Figure 6 , Figure 9 , Figure 11 and Figure 13 As shown, in some exemplary embodiments, the central region 3023 and the edge region 3024 are connected by connecting ribs 3025, which are a plurality of ribs arranged at intervals around the central region 3023.

[0053] As described above, the multiple spaced connecting ribs 3025 not only ensure connection strength but also allow the electrolyte to pass through through the holes between each connecting rib 3025. In addition, it can reduce the weight of the entire shielding part 302 to a certain extent, optimize the product structure, and reduce the amount of materials used in production. The spaced arrangement of the connecting ribs 3025 ensures that each part can be evenly stressed during the bending process of the shielding part 302, reducing the risk of damage caused by stress concentration and improving the durability of the shielding part 302.

[0054] Continue to refer to Figure 6 , Figure 9 , Figure 11 and Figure 13 As shown, in a preferred embodiment, connecting ribs 3025 are provided on both sides of the central region 3023, and multiple connecting ribs 3025 on each side are arranged at intervals. For example, connecting ribs 3025 are provided on both sides of the central region 3023 along the length direction of the cover plate 1, and there are four connecting ribs 3025 on each side, and the four connecting ribs 3025 on each side are arranged at intervals along the width direction of the cover plate 1.

[0055] Meanwhile, the interval between any adjacent connecting ribs 3025 on each side can be used for the passage of electrolyte. Along the width direction of the cover plate 1, both sides of the central region 3023 are provided with strip holes 3028, each strip hole 3028 extends along the length direction of the cover plate 1, and the length of each strip hole 3028 is greater than the size of the groove 3022 in the length direction of the cover plate 1, so that the central region 3023 is connected only by the connecting ribs 3025 on both sides in the length direction.

[0056] In another example, the central region 3023 is provided with a plurality of connecting ribs 3025 circumferentially, and the plurality of connecting ribs 3025 are arranged at intervals around the central region 3023. Specifically, along the length direction of the cover plate 1, the connecting ribs 3025 on both sides of the central region 3023 are consistent with those described above. In addition, along the width direction of the cover plate 1, the central region 3023 is also provided with connecting ribs 3025 on both sides, and the connecting ribs 3025 on both sides are arranged at intervals along the length direction of the cover plate 1.

[0057] It should be noted that the number of 3025 connecting ribs on each side can be arranged according to actual needs and is not limited to this. Figure 13 The four shown can be, for example, one, three, six, etc. In the structure above, the central region 3023 and the edge region 3024 are connected by connecting ribs 3025. A gap is set between adjacent connecting ribs 3025, which allows the electrolyte to flow through the gap. In addition, this connection method is also beneficial for protecting the central vibration of the part, and the amount of material used is also less, which helps to save costs.

[0058] Based on the presence of connecting ribs 3025, refer to Figure 13 As shown, in some exemplary embodiments, the length L of the connecting rib 3025 is between 3.0mm and 10mm, and the width W of the connecting rib 3025 is between 0.5mm and 5mm. This size range is optimized to ensure that the connecting rib 3025 has sufficient strength to connect the central region 3023 and the edge region 3024, while avoiding excessive weight increase or space occupation of the entire shielding part 302 due to excessive size. While ensuring structural strength, the product achieves lightweight and miniaturized design.

[0059] At the same time, refer to Figure 6As shown, in some exemplary embodiments, the effective depth h of the groove 3022 is between 0.3mm and 8mm, such as 0.3mm, 4mm, 6mm, 8mm, etc. It should be noted that the effective depth of the groove 3022 refers to the distance between the bottom wall of the space between adjacent connecting ribs 3025 and the bottom wall of the groove 3022. Secondly, the total depth H of the groove 3022 is between 1.2mm and 6.5mm, such as 1.5mm, 4mm, 6mm, 8.5mm, etc. The effective depth h of the groove 3022 being between 0.3mm and 8mm ensures that the groove 3022 can accommodate welding slag without excessively occupying the internal space of the power battery. The total depth H of the groove 3022 being between 1.2mm and 6.5mm ensures that the through holes between the connecting ribs 3025 provide sufficient electrolyte flow without excessively occupying the internal space of the power battery.

[0060] Regarding the connection method between the obstruction part 302 and the main body part 301, refer to Figure 2 , Figure 7 , Figure 8 , Figure 9 and Figure 10 As shown, in some exemplary embodiments, the blocking portion 302 is connected to the body portion 301 by a snap-fit ​​part, and the snap-fit ​​part includes a buckle 304 provided on the body portion 301 and a snap-fit ​​hole 3026 provided on the blocking portion 302, the buckle 304 being able to be snapped into the snap-fit ​​hole 3026.

[0061] In this way, the shielding part 302 and the main body part 301 are connected by a snap-fit ​​part. The snap-fit ​​method is simple and convenient to operate, and is easy to install and disassemble during the production process. Compared with other connection methods, the snap-fit ​​part does not require the use of additional connection tools or connectors, which reduces production costs. Moreover, the snap-fit ​​structure is simple and reliable in design, and can provide sufficient connection strength to ensure that the shielding part 302 is firmly connected to the main body part 301 after bending, and maintain the effective shielding of the electrode tab 401 and the welding part of the electrode post 2 by the shielding part 302.

[0062] Based on the connection between the blocking portion 302 and the main body portion 301 via a snap fastener 304 and a snap-fit ​​hole 3026, in some exemplary embodiments, the blocking portion 302 has a protrusion 3027 protruding towards one side of the main body portion 301, and the snap-fit ​​hole 3026 is provided at the protrusion 3027 and extends through the blocking portion 302. After snapping, the blocking portion 302 abuts against the main body portion 301 via the protrusion 3027.

[0063] With this configuration, a protrusion 3027 is provided on the shielding part 302, and the snap-fit ​​hole 3026 is located on the protrusion 3027 and extends through the shielding part 302. This provides sufficient depth for the snap-fit ​​304 to engage, improving the reliability and stability of the connection. At the same time, after the shielding part 302 engages with the main body part 301, the protrusion 3027 can also play a limiting role, restricting the minimum distance between the shielding part 302 and the main body part 301.

[0064] Meanwhile, based on the connection between the blocking portion 302 and the main body portion 301 via a snap fastener 304 and a snap-fit ​​hole 3026, in some exemplary embodiments, the snap fastener 304 includes a plurality of sub-snap fasteners 3041 spaced circumferentially along the snap-fit ​​hole 3026. Each sub-snap fastener 3041 has a connecting block 30411 connected to the main body portion 301, and a snap-fit ​​block 30412 protruding radially outward from the connecting block 30411. The snap fastener 304 is engaged with the blocking portion 302 via the snap-fit ​​block 30412.

[0065] In this way, the buckle 304 includes multiple sub-buckles 3041, each of which includes a snap-fit ​​block 30412 and a connecting block 30411. When the buckle 304 is snapped into the snap-fit ​​hole 3026, the multiple snap-fit ​​blocks 30412 shift together towards the center line of the buckle 304, so that the snap-fit ​​blocks 30412 can be smoothly snapped into the snap-fit ​​hole 3026. The snap-fit ​​process is convenient, and after the snap-fit ​​is completed, each snap-fit ​​block 30412 is reset under the action of its respective connecting block 30411, so that the buckle 304 can be firmly snapped into the snap-fit ​​hole 3026. The reliability and stability of the snap-fit ​​are high.

[0066] Furthermore, based on the buckle 304 including multiple sub-buckles 3041, in some exemplary embodiments, the snap-fit ​​hole 3026 includes a first snap-fit ​​hole 30261 and a second snap-fit ​​hole 30262 that are connected to each other. The diameter of the first snap-fit ​​hole 30261 is smaller than the diameter of the second snap-fit ​​hole 30262. The connecting block 30411 is inserted into the first snap-fit ​​hole 30261, and the snap-fit ​​block 30412 is snapped into the second snap-fit ​​hole 30262.

[0067] The connecting block 30411 is inserted into the first locking hole 30261, and the locking block 30412 is locked in the second locking hole 30262. This design of the locking hole 3026 forms a stepped locking structure. The first locking hole 30261 limits the connecting block 30411, and the second locking hole 30262 limits the locking block 30412, so that a firm locking structure is formed between the buckle 304 and the locking hole 3026. Moreover, the locking block 30412 is located in the second locking hole 30262, which is not easily affected by external impacts and can be held relatively stably in the second locking hole 30262. It is also not easy to scratch the tab 401.

[0068] In addition, the material of the insulation structure 3 can refer to the existing materials of plastics, such as polypropylene (PP). Since polypropylene has excellent electrical insulation and impact resistance, it can not only effectively insulate the cover plate 1 from the pole post 2, but also improve the damping effect of the central region 3023 on the vibration of the pole group 4 by utilizing its own excellent elasticity.

[0069] To better understand the assembly process of the cover plate assembly in this embodiment, for example... Figure 14 As shown, the tab 401 of the electrode assembly 4 is welded to the electrode post 2, and the main body 301 is connected to the cover plate 1. This is a schematic diagram of the structure of the shielding part 302 before it is bent. And as... Figure 15 The diagram shown is a structural schematic of the shielding portion 302 bending to one side of the main body portion 301 and blocking the opposite side of the corresponding tab 401 facing the cover plate 1.

[0070] It is worth noting that, regarding the cover plate assembly of this embodiment, based on the above exemplary embodiments, in specific implementation, as a preferred embodiment, it is still composed of... Figures 1 to 14 As shown, it includes a cover plate 1, an pole post 2, and an insulating structure 3.

[0071] The insulating structure 3 includes a main body portion 301, a connecting portion 303, and a shielding portion 302 that are connected and integrally formed. The shielding portion 302 includes an edge region 3024 and a central region 3023. The edge region 3024 and the central region 3023 are connected by a connecting rib 3025. When the shielding portion 302 is flipped to the side of the main body portion 301 facing away from the cover plate 1, it can be snapped into the main body portion 301.

[0072] The main body 301 is provided with a buckle 304, and the covering part 302 is provided with a locking hole.

[0073] In the preferred embodiment of the above cover plate assembly, the specific configuration and arrangement of the cover plate 1, pole post 2, insulation structure 3, etc. can still be referred to the descriptions in the above exemplary embodiments. Furthermore, in this preferred embodiment, the beneficial effects brought about by the design of the cover plate 1, pole post 2, insulation structure 3, etc. can also be referred to the descriptions in the above exemplary embodiments.

[0074] The cover plate assembly of this embodiment adopts the above design. By setting the insulating structure 3, the shielding part 302 is placed on the side of the main body part 301 facing away from the cover plate 1. A space for accommodating the tab 401 can be formed between the shielding part 302 and the main body part 301. The electrode post 2 passing through the cover plate 1 can be welded to the tab 401. The welding slag generated by welding will be blocked by the shielding part 302. At the same time, the groove 3022 on the shielding part 302 corresponding to the electrode post 2 can accommodate the welding slag generated by welding, making it difficult for the welding slag to enter the electrode group 4, reducing the risk of the separator being punctured. Using the cover plate assembly in the power battery is beneficial to improving the safety of the power battery.

[0075] An embodiment of the second aspect of this application provides a power battery, the casing of which is provided with the cover plate assembly of the first aspect embodiment.

[0076] In this embodiment of the power battery, by providing the aforementioned cover assembly on the casing, the shielding portion 302 in the cover assembly can block the side of the main body portion 301 facing away from the cover 1, and a space for accommodating the tab 401 can be formed between the shielding portion 302 and the main body portion 301. The electrode post 2 passing through the cover 1 can be welded to the tab 401. The welding slag generated by welding will be blocked by the shielding portion 302. At the same time, the groove 3022 provided on the shielding portion 302 corresponding to the electrode post 2 can accommodate the welding slag generated by welding, making it difficult for the welding slag to enter the electrode group 4, reducing the risk of the separator being punctured, and improving the safety of the power battery.

[0077] The above descriptions are merely some embodiments of this application and are not intended to limit this application. The technical features or structures in the foregoing different embodiments can be arbitrarily combined to form other specific technical solutions as needed. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of the claims of this application.

Claims

1. A cover plate assembly, characterized in that: It includes a cover plate equipped with an explosion-proof valve, an electrode post passing through the cover plate, and an insulating structure located on one side of the cover plate that can insulate the cover plate and the electrode post; The cover plate is elongated, and the insulating structure includes a body portion conforming to the shape of the cover plate, and a shielding portion connected to the body portion in the width direction of the body portion; The shielding portion can be bent to one side of the thickness direction of the main body portion, and the bent shielding portion extends along the length direction of the main body portion. The bent shielding portion can be connected to the main body portion and block the side of the main body portion facing away from the cover plate. The shielding portion is provided with a through hole corresponding to the explosion-proof valve and a groove corresponding to the pole post, and the groove is recessed towards the side away from the main body portion.

2. The cover plate assembly according to claim 1, characterized in that: The shielding portion is connected to the main body portion through a thinned connecting portion, and the shielding portion, the connecting portion, and the main body portion are integrally formed by injection molding.

3. The cover plate assembly according to claim 2, characterized in that: The shielding portion has a central region corresponding to the pole post and an edge region surrounding the central region; The groove is formed by recessing the central region toward the side away from the body portion.

4. The cover plate assembly according to claim 3, characterized in that: The central region and the edge region are connected by connecting ribs, which are multiple ribs arranged at intervals around the central region.

5. The cover plate assembly according to claim 4, characterized in that: The length L of the connecting rib is between 3.0mm and 10mm, and the width W of the connecting rib is between 0.5mm and 5mm; and / or, The effective depth h of the groove is between 0.3mm and 8mm, and the total depth H of the groove is between 1.2mm and 6.5mm.

6. The cover plate assembly according to any one of claims 1-5, characterized in that: The shielding portion is connected to the main body portion by a snap-fit ​​part, and the snap-fit ​​part includes a buckle provided on the main body portion and a snap-fit ​​hole provided on the shielding portion, and the buckle can be snapped into the snap-fit ​​hole.

7. The cover plate assembly according to claim 6, characterized in that: The shielding portion has a protrusion that protrudes toward one side of the main body portion, and the snap-fit ​​hole is provided at the protrusion and penetrates the shielding portion; After being snapped in, the blocking portion abuts against the main body portion via the protrusion.

8. The cover plate assembly according to claim 6, characterized in that: The buckle includes a plurality of sub-buckles spaced circumferentially along the snap-fit ​​hole, each sub-buckle having a connecting block connected to the main body portion, and a snap-fit ​​block protruding radially outward from the connecting block. The buckle is engaged with the blocking portion via the snap-fit ​​block.

9. The cover plate assembly according to claim 8, characterized in that: The snap-fit ​​hole includes a first snap-fit ​​hole and a second snap-fit ​​hole that are connected to each other, wherein the diameter of the first snap-fit ​​hole is smaller than the diameter of the second snap-fit ​​hole; The connecting block is inserted into the first card hole, and the snap-fit ​​block is snapped into the second card hole.

10. A power battery, characterized in that: The power battery casing is provided with a cover plate assembly as described in any one of claims 1-9.

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