Battery cover plate, battery pack and electric device

Abstract

The embodiment of the application provides a battery cover plate, a battery pack and an electric equipment, and relates to the technical field of battery detection. The battery cover plate comprises: a cover plate; a sealing piece, which is used for sealing a liquid injection hole on the cover plate; a sealing element, which is connected with the cover plate, and a sealing space is formed between the sealing element and the cover plate, and the sealing piece is located in the sealing space; and a helium suction element, which is arranged in the sealing space. The battery cover plate, the battery pack and the electric equipment can improve the accuracy of the sealing performance detection between the cover plate and the sealing element.

Description

Technical Field

[0001] This application relates to the field of battery testing technology, and in particular to a battery cover, a battery pack, and an electrical device. Background Technology

[0002] During battery manufacturing, electrolyte needs to be injected into the battery through the injection hole on the battery cover. After the injection is completed, the injection hole needs to be sealed to prevent electrolyte leakage.

[0003] In related technologies, a battery cover plate includes a cover plate, a sealing element, and a sealing element. The cover plate has an injection hole, the sealing element is used to close the injection hole, and the sealing element is placed on the cover plate. A sealed space is formed between the sealing element and the cover plate to cover the sealing element. To test the sealing performance between the sealing element and the cover plate, a back pressure helium detection method is usually used. During the test, helium is first filled into the sealed space, then the cover plate is placed in a vacuum environment and the gas is evacuated. Finally, the detection equipment is used to observe whether helium escapes from the outside of the sealing element to determine whether there is a leak.

[0004] However, when the leakage hole between the seal and the cover plate is small, helium slowly escapes, and residual helium can still be detected after vacuuming, thus enabling the detection equipment to determine the leak. But when the leakage hole between the seal and the cover plate is large, the vacuuming process may remove all the helium in the sealed space, causing the detection equipment to be unable to capture the helium signal, resulting in misjudgment and reducing the accuracy of the sealing performance test between the seal and the cover plate. Utility Model Content

[0005] This application provides a battery cover, a battery pack, and an electrical device to solve the technical problem that when the leakage hole between the seal and the cover is large, the back pressure helium detection method cannot accurately detect it, thereby reducing the accuracy of the sealing performance test between the seal and the cover.

[0006] In a first aspect, embodiments of this application provide a battery cover, comprising:

[0007] Cover plate;

[0008] A sealing element, the sealing element being used to seal the injection hole on the cover plate;

[0009] A sealing element is connected to the cover plate, and a sealing space is formed between the sealing element and the cover plate, with the sealing element located within the sealing space;

[0010] A helium-absorbing element is disposed within the sealed space.

[0011] In some embodiments, the sealing element has a groove on the side facing the sealing element, and the groove is disposed opposite to the helium-absorbing element.

[0012] In some embodiments, the distance between the bottom of the groove and the sealing element is greater than or equal to the thickness of the helium-absorbing element.

[0013] In some embodiments, along the thickness direction of the cover plate, the projection of the helium-absorbing element on the cover plate is located within the projection range of the groove on the cover plate.

[0014] In some embodiments, the helium-absorbing element is connected to the bottom of the groove, or the helium-absorbing element is connected to the side of the sealing element near the groove.

[0015] In some embodiments, an adhesive element is also included, which is connected to the helium-absorbing element, and the helium-absorbing element is fixed to the groove or the sealing element by the adhesive element.

[0016] In some embodiments, the helium-absorbing element is one of activated carbon sheet, rubber sheet, silicone sheet, and foamed plastic sheet.

[0017] In some embodiments, the helium-absorbing element is an activated carbon sheet, which comprises activated carbon powder and an adhesive, wherein the mass ratio of the activated carbon powder to the adhesive is 1-20:1.

[0018] In some embodiments, at least a portion of the particles in the activated carbon powder have a diameter of 5 μm to 20 μm.

[0019] In some embodiments, the surface area of ​​the activated carbon powder is 500 m² / g to 1500 m² / g.

[0020] In some embodiments, the cover plate is provided with a groove, and the injection hole is provided on the bottom wall of the groove, the groove being used to accommodate the sealing member.

[0021] In some embodiments, the sealing member includes an abutment portion and an insertion portion, the abutment portion being connected to the insertion portion, the insertion portion being used to insert into the injection hole so that the abutment portion abuts against the bottom wall of the tank, the tank being used to accommodate the abutment portion.

[0022] In some embodiments, the abutting part is a plastic plate, and the insertion part is a rubber plug.

[0023] In some embodiments, the cover plate is provided with a receiving groove along the circumference of the groove body, the receiving groove being used to receive the circumferential edge of the seal.

[0024] Secondly, embodiments of this application provide a battery pack, including a housing and a battery cover plate connected to the housing.

[0025] Thirdly, embodiments of this application provide an electrical device, including a device body and the battery pack connected to the device body.

[0026] This application provides a battery cover, a battery pack, and an electrical device. By employing a helium-absorbing element, when testing the sealing performance between the seal and the cover, helium is first filled into the sealed space. The helium-absorbing element within the sealed space can absorb and store helium. When the cover is placed in a vacuum environment and the vacuum is evacuated, the helium stored in the helium-absorbing element can be slowly released. When the leakage between the seal and the cover is small, the helium can be continuously released and detected by the testing equipment. This facilitates determining whether there is a leak when the leakage between the seal and the cover is small, and when the leakage between the seal and the cover is large, even if... The vacuuming process removes helium from the sealed space, but some helium can still be continuously released through the helium-absorbing component and detected by the testing equipment. This facilitates the determination of leakage when there is a significant leak between the seal and the cover plate, reducing the possibility of missed detections due to the complete removal of helium, and indirectly improving the accuracy of the sealing performance test between the seal and the cover plate. By using a sealing element and a closure element, a secondary seal is achieved for the injection hole, thereby improving the sealing performance of the injection hole. Furthermore, by sealing the closure element with the closure element, the closure element is prevented from being exposed and damaged, indirectly increasing the service life of the closure element. Attached Figure Description

[0027] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0028] Figure 1 Schematic diagram of the structure of the battery cover provided in this application Figure 1 ;

[0029] Figure 2 for Figure 1 A schematic diagram of the structure of the helium-absorbing component, the adhesive component, and the contact part;

[0030] Figure 3 Schematic diagram of the structure of the battery cover provided in this application Figure 2 ;

[0031] Figure 4 for Figure 3 Schematic diagram of the structure of the sealing component, helium-absorbing component, and adhesive component.

[0032] Explanation of reference numerals in the attached figures:

[0033] 100. Cover plate; 110. Injection hole; 120. Tank body; 130. Receiving tank;

[0034] 200. Sealing part; 210. Abutting part; 220. Inserting part;

[0035] 300, Seal; 310, Sealing space; 330, Groove;

[0036] 400. Helium-absorbing components;

[0037] 500. Adhesive parts.

[0038] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0039] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0040] In existing technical solutions, the battery cover plate includes a cover plate, a sealing component, and a sealing component. The cover plate has an injection hole, the sealing component is used to directly close the injection hole, and the sealing component covers the outside of the sealing component and forms a sealed space with the cover plate by welding. To test the welding seal between the sealing component and the cover plate, the back pressure helium test method is commonly used. The specific test process consists of three steps: first, helium gas at a certain pressure is injected into the sealed space; then, the entire component is placed in a vacuum environment for vacuuming; finally, a high-sensitivity detection device is used to detect whether helium gas escapes from the periphery of the sealing component. By measuring the amount of helium gas leakage, it is possible to accurately determine whether the sealing performance meets the standards.

[0041] The effectiveness of this detection method depends on the size of the leak hole. When there is a small leak hole, helium will slowly seep out, and after vacuuming, a sufficient helium concentration will remain in the sealed space, allowing the detection equipment to reliably identify the leak. However, when the leak hole is too large, helium will be lost rapidly during vacuuming, causing the helium concentration in the sealed space to drop below the detection limit, making it impossible for the detection equipment to identify the actual leak, thus resulting in a false judgment. This detection blind zone mainly occurs when there are obvious defects in the weld (such as incomplete penetration or burn-through), which seriously affects the detection rate of large-sized leak defects.

[0042] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0043] Combination Figures 1 to 4 This application provides a battery cover, comprising:

[0044] Cover plate 100;

[0045] Sealing component 200 is used to seal the injection hole 110 on the cover plate 100;

[0046] A sealing element 300 is connected to a cover plate 100, and a sealing space 310 is formed between the sealing element 300 and the cover plate 100. A sealing element 200 is located within the sealing space 310.

[0047] Helium suction element 400 is installed inside the sealed space 310.

[0048] In this application, by employing a helium-absorbing element 400, when it is necessary to test the sealing performance between the seal 300 and the cover plate 100, helium is first filled into the sealed space 310. The helium-absorbing element 400 located within the sealed space 310 can absorb and store helium. When the cover plate 100 is placed in a vacuum environment for evacuation, the helium stored in the helium-absorbing element 400 can be slowly released. When the leakage between the seal 300 and the cover plate 100 is small, the helium can be continuously released and detected by the testing equipment. This facilitates determining whether there is a leak when the leakage between the seal 300 and the cover plate 100 is small. When the leakage between the seal 300 and the cover plate 100 is large, even if the vacuum process fills the sealed space... Although helium gas is extracted from chamber 310, some helium gas can still be continuously released through helium suction component 400 and detected by the detection equipment. This facilitates the determination of whether there is a leak when the leakage between seal component 300 and cover plate 100 is large, reducing the phenomenon of the detection equipment missing the detection due to the complete extraction of helium gas, and indirectly improving the accuracy of the sealing performance detection between seal component 300 and cover plate 100. By using sealing component 200 and seal component 300, a secondary seal is achieved for injection hole 110, thereby improving the sealing performance of injection hole 110. Furthermore, by sealing sealing component 300 with sealing component 200, sealing component 200 is prevented from being exposed and damaged, indirectly improving the service life of sealing component 200.

[0049] In this embodiment, the seal 300 and the cover plate 100 are connected by laser welding. Laser welding can achieve extremely high precision, and the weld width can be controlled at the micrometer level, ensuring the uniformity and consistency of the weld, thereby improving the sealing performance between the seal 300 and the cover plate 100. Secondly, the heat input during laser welding is relatively small, and the thermal impact on the surrounding materials is small, avoiding the decline in the sealing performance of the cover plate 100 and other components due to thermal deformation. In addition, laser welding can achieve rapid welding, improve production efficiency, and the weld has high strength, which can withstand greater pressure and stress, ensuring that the connection between the seal 300 and the cover plate 100 is firm and reliable during long-term use, effectively preventing electrolyte leakage.

[0050] In other embodiments, the seal 300 and the cover plate 100 can be bolted together, and a sealing ring can be provided between the seal 300 and the cover plate 100 so that the sealing ring can also achieve the sealing between the seal 300 and the cover plate 100.

[0051] Combination Figures 1 to 4 The sealing element 300 has a groove 330 on the side facing the sealing element 200, and the groove 330 is positioned opposite to the helium-absorbing element 400.

[0052] In this application, by adopting the setting of the groove 330, the groove 330 can reserve space for the arrangement of the helium-absorbing component 400, which makes it easier to place the helium-absorbing component 400 between the sealing component 300 and the sealing component 200, thereby reducing the space occupied by the cover plate 100, the helium-absorbing component 400 and the sealing component 200.

[0053] In this embodiment, the sealing element 300 is set as a circular plate, which is flat. When the sealing element 300 is connected to the cover plate 100, the sealing element 300 will not protrude much from the cover plate 100, thereby preventing the sealing element 300 from interfering with other components and reducing the space occupied by the sealing element 300.

[0054] In other embodiments, the shape of the seal 300 can be adapted as needed. For example, the cross-section of the seal 300 can be set to an arc shape so that the recess of the arc-shaped seal 300 can accommodate the sealing member 200 and the arc-shaped seal 300 has better strength. Alternatively, the cross-section of the seal 300 can be set to a wave shape or a spherical shape, etc.

[0055] In this embodiment, the groove 330 is circular, and the helium-absorbing component 400 is configured to cooperate with the circular groove 330. By setting the groove 330 to be circular and configuring the helium-absorbing component 400 to cooperate with the circular groove 330, it is convenient to manufacture and process the circular groove 330 and the circular helium-absorbing component 400.

[0056] In other embodiments, the shapes of the groove 330 and the helium-absorbing element 400 can be adapted as needed. For example, the groove 330 can be set as a rectangle and the helium-absorbing element 400 can be matched with the rectangular groove 330, or the groove 330 can be set as a hemispherical shape and the helium-absorbing element 400 can be matched with the hemispherical groove 330.

[0057] In this embodiment, the diameter of the groove 330 gradually decreases along the direction of the sealing member 200 near the sealing member 300. By gradually reducing the diameter of the groove 330, when the helium-absorbing member 400 is installed in the groove 330, the groove 330 can guide the helium-absorbing member 400, thereby facilitating the installation of the helium-absorbing member 400. Furthermore, by gradually reducing the diameter of the groove 330, a gap is formed between the sidewall of the groove 330 and the helium-absorbing member 400, thereby indirectly increasing the contact area between the helium-absorbing member 400 and the air, allowing the helium-absorbing member 400 to absorb more helium.

[0058] In other embodiments, the diameter of the groove 330 gradually increases along the direction of the sealing member 200 near the sealing member 300, so that when the helium-absorbing member 400 is installed in the groove 330, the helium-absorbing member 400 can be confined within the groove 330 to prevent the helium-absorbing member 400 from detaching from the groove 330; or the diameter of the groove 330 is equal at all positions along the direction of the sealing member 200 near the sealing member 300, thereby facilitating the processing of the groove 330.

[0059] Combination Figures 1 to 4 The distance between the bottom of the groove 330 and the sealing part 200 is greater than or equal to the thickness of the helium-absorbing part 400.

[0060] In this embodiment, the distance between the bottom of the groove 330 and the sealing member 200 is greater than the thickness of the helium-absorbing member 400, thereby allowing one side of the helium-absorbing member 400 to be separated from the groove 330 or the sealing member 300. This indirectly increases the contact area between the helium-absorbing member 400 and the air, enabling the helium-absorbing member 400 to absorb more helium. This prevents all the helium absorbed by the helium-absorbing member 400 from being sucked away during the vacuuming process, thereby further improving the accuracy of the sealing detection of the sealing member 300 and the cover plate 100.

[0061] In some embodiments, the distance between the bottom of the groove 330 and the sealing member 200 is equal to the thickness of the helium-absorbing member 400. At this time, one side of the helium-absorbing member 400 can be connected to the groove 330, and the other side of the helium-absorbing member 400 can be connected to the sealing member 200, thereby improving the fixing strength of the helium-absorbing member 400 between the groove 330 and the sealing member 200, and preventing the helium-absorbing member 400 from moving in the sealed space 310 due to the vacuuming pressure.

[0062] Combination Figures 1 to 4Along the thickness direction of the cover plate 100, the projection of the helium-absorbing element 400 on the cover plate 100 is located within the projection range of the groove 330 on the cover plate 100.

[0063] In this embodiment, along the direction of the sealing member 200 near the sealing member 300, the diameter of the groove 330 gradually decreases, and the minimum area of ​​the groove 330 is larger than the area of ​​the helium-absorbing member 400. By making the area of ​​the groove 330 larger than the area of ​​the helium-absorbing member 400, interference between the groove 330 and the helium-absorbing member 400 is prevented when the sealing member 300 is installed, and the groove 330 is prevented from affecting the adsorption performance of the helium-absorbing member 400. Furthermore, when part of the helium-absorbing member 400 moves into the groove 330, the gap between the helium-absorbing member 400 and the sidewall of the groove 330 is larger, thereby accommodating more helium for the helium-absorbing member 400 to adsorb.

[0064] In some embodiments, along the direction of the sealing member 200 near the sealing member 300, the diameter of each position of the groove 330 is the same, and the area of ​​the groove 330 is equal to the area of ​​the helium absorber 400. By making the area of ​​the groove 330 equal to the area of ​​the helium absorber 400, when the sealing member 300 is installed, interference between the helium absorber 400 and the sidewall of the groove 330 can also be prevented, and the groove 330 can be prevented from affecting the adsorption performance of the helium absorber 400.

[0065] In other embodiments, multiple grooves 330 can be provided, and multiple protrusions that cooperate with the grooves 330 can be provided on the adsorption member. Some of the protrusions are inserted into the grooves 330. By using multiple protrusions, the contact area between the helium adsorption member 400 and the air is indirectly increased, thereby further improving the adsorption performance of the helium adsorption member 400. By cooperating with the grooves 330, the position of the helium adsorption member 400 can be positioned to prevent the helium adsorption member 400 from deviating from the sealed space 310.

[0066] Combination Figures 1 to 4 The helium-absorbing component 400 is connected to the bottom of the groove 330, or the helium-absorbing component 400 is connected to the side of the sealing component 200 near the groove 330.

[0067] Combination Figure 1 and Figure 2 In this embodiment, the helium-absorbing component 400 is connected to the sealing component 200 on the side near the groove 330. By connecting the helium-absorbing component 400 and the sealing component 200, the sealing component 200 can support the helium-absorbing component 400, thereby improving the fixing strength of the helium-absorbing component 400. When installing the sealing component 300, the helium-absorbing component 400 and the sealing component 200, the sealing component 200 needs to be installed first, then the helium-absorbing component 400, and finally the sealing component 300.

[0068] Combination Figure 3 and Figure 4In some embodiments, the helium-absorbing component 400 is connected to the bottom of the groove 330. By connecting the helium-absorbing component 400 to the groove 330, when installing the seal 300, the helium-absorbing component 400, and the sealing component 200, the helium-absorbing component 400 and the groove 330 can be prefabricated in the factory. By installing the sealing component 200 to the liquid injection hole 110 and connecting the seal 300 to the cover plate 100, the assembly of the entire battery cover plate can be realized. The assembly method is convenient and simple. Furthermore, when helium enters the sealed space 310, the helium can flow towards the upper helium-absorbing component 400, thereby enabling the helium-absorbing component 400 to better absorb helium and indirectly improving the absorption efficiency of the helium-absorbing component 400.

[0069] In other embodiments, a rod can be provided between the groove 330 and the sealing member 200, and the helium-absorbing member 400 can be placed on the rod, so that the rod can drive the helium-absorbing member 400 to be mounted in the middle of the sealed space 310, thereby separating the helium-absorbing member 400 from the groove 330 and the sealing member 200, thereby further increasing the contact area between the helium-absorbing member 400 and the air, so that the helium-absorbing member 400 can absorb more helium.

[0070] Combination Figures 1 to 4 The battery cover also includes an adhesive piece 500, which is connected to the helium-absorbing piece 400. The helium-absorbing piece 400 is fixed to the groove 330 or the sealing piece 200 by the adhesive piece 500.

[0071] In this application, by adopting the adhesive part 500, the helium-absorbing part 400 can be easily fixed to the groove 330 or the sealing part 200 by the adhesive part 500, which improves the convenience of fixing the helium-absorbing part 400 and improves the fixing strength of fixing the helium-absorbing part 400 to the groove 330 or the sealing part 200.

[0072] In this embodiment, the adhesive 500 is at least one of an epoxy resin layer, a phenolic resin layer, and an acrylic resin.

[0073] The epoxy resin layer has excellent adhesion properties, enabling it to form a strong bond with the groove 330 or the sealing element 200. The epoxy resin layer also has good mechanical strength and chemical corrosion resistance, maintaining a stable bonding effect under harsh environmental conditions. In addition, the epoxy resin layer has a low shrinkage rate, which will not generate excessive stress on the helium absorber 400 during the curing process, thereby ensuring the dimensional stability and structural integrity of the helium absorber 400.

[0074] The phenolic resin layer maintains stable bonding performance at high temperatures and is not easily decomposed or burned. It also has good electrical insulation properties, making it suitable for fixing electronic and electrical equipment. In addition, the phenolic resin layer has high hardness and wear resistance, providing good mechanical protection and preventing objects from being worn or damaged during use.

[0075] The acrylic resin layer has good weather resistance and UV resistance, and can be used in outdoor environments for a long time without aging or discoloration. The acrylic resin layer also has good flexibility and elasticity, which can adapt to changes in the shape of the object and slight mechanical deformation, thus providing a reliable bonding effect.

[0076] In other embodiments, the helium-absorbing component 400 can also be fixed to the groove 330 or the sealing component 200 by means of snap-fit ​​or bolt connection.

[0077] The helium-absorbing element 400 is one of activated carbon sheet, rubber sheet, silicone sheet, and foamed plastic sheet.

[0078] In this application, the activated carbon sheet possesses an extremely high specific surface area and abundant microporous structure, enabling it to efficiently adsorb helium. During backpressure helium detection, the activated carbon sheet can adsorb leaked helium, increasing the residence time of helium within the sealed space 310, thereby improving the probability of the detection equipment capturing helium. Furthermore, the adsorption performance of the activated carbon sheet remains stable over a wide range of temperature and pressure, adapting to different detection conditions and effectively improving the accuracy and reliability of the detection.

[0079] The rubber sheet has good adsorption properties and can adsorb leaked helium, thereby increasing the residence time of helium in the sealed space 310. During the back pressure helium detection process, the adsorption effect of the rubber sheet can ensure that the helium has sufficient residence time in the sealed space 310, enabling the detection equipment to capture the helium signal more effectively and improve the accuracy of the detection.

[0080] Silica gel sheets have excellent chemical and thermal stability, and can maintain stable adsorption performance in high temperature and chemically corrosive environments. During back pressure helium detection, silica gel sheets can adsorb leaked helium, increase the residence time of helium in the sealed space 310, and increase the probability of the detection equipment capturing helium.

[0081] The foamed plastic sheet has a lightweight and porous structure, which can provide a large adsorption surface area, thus effectively adsorbing leaked helium. During back pressure helium detection, the foamed plastic sheet can increase the residence time of helium in the sealed space 310, and increase the probability of the detection equipment capturing helium.

[0082] The helium-absorbing component 400 is an activated carbon sheet, which consists of activated carbon powder and an adhesive, with a mass ratio of activated carbon powder to adhesive of 1-20:1.

[0083] In this application, by increasing the mass of activated carbon powder, the activated carbon powder provides an extremely high specific surface area and abundant microporous structure, which can efficiently adsorb leaked helium gas and significantly increase the residence time of helium gas in the sealed space 310, thereby further improving the detection accuracy of back pressure helium detection; at the same time, the addition of adhesive ensures the structural stability of the activated carbon sheet, making it less likely to break or fall off during the detection process, thus ensuring the continuity and reliability of adsorption performance.

[0084] At least some of the particles in the activated carbon powder have a diameter of 5μm-20μm.

[0085] In this embodiment, 50% of the particles in the activated carbon powder have a diameter of 5μm-20μm.

[0086] In this application, the smaller particle size can significantly increase the specific surface area of ​​activated carbon, thereby providing more adsorption sites and greatly improving the adsorption efficiency of helium. While ensuring high adsorption performance, it also avoids the dust problem that may be caused by excessively small particles and the uneven adsorption problem that may be caused by excessively large particles. In addition, particles of this size range can be better mixed with adhesives when preparing activated carbon sheets, ensuring the structural uniformity and stability of activated carbon sheets, further improving their application performance in back pressure helium detection, and effectively improving the accuracy and reliability of detection.

[0087] The surface area of ​​activated carbon powder is 500m² / g-1500m² / g.

[0088] In this application, the high specific surface area means that the activated carbon powder provides a large number of micropores and adsorption sites, which can greatly improve the adsorption capacity of helium, thereby significantly increasing the residence time of helium in the sealed space 310. This enables the detection device to capture the helium signal more effectively and improve the detection accuracy of back pressure helium detection.

[0089] Combination Figures 1 to 4 The cover plate 100 is provided with a tank 120, and the injection hole 110 is provided on the bottom wall of the tank 120. The tank 120 is used to accommodate the sealing component 200.

[0090] In this application, by adopting the arrangement of the groove 120, the groove 120 can accommodate the sealing member 200, preventing the sealing member 200 protruding from the cover plate 100 from interfering with other components in the battery pack, thereby indirectly reducing the space occupied by the cover plate 100 and the sealing member 200.

[0091] In this embodiment, the cross-section of the tank 120 is U-shaped. In other embodiments, the shape of the tank 120 can be adjusted as needed, for example, the cross-section of the tank 120 can be set to an arc or a V-shape.

[0092] Combination Figures 1 to 4 The sealing member 200 includes an abutment portion 210 and an insertion portion 220. The abutment portion 210 is connected to the insertion portion 220. The insertion portion 220 is used to insert into the injection hole 110 so that the abutment portion 210 abuts against the bottom wall of the tank 120. The tank 120 is used to accommodate the abutment portion 210.

[0093] In this application, when it is necessary to close the injection hole 110, the insertion part 220 is inserted into the injection hole 110. At this time, the abutment part 210 can abut against the bottom wall of the tank 120, so that the abutment part 210 can limit the position of the insertion part 220, preventing the insertion part 220 from entering the battery casing, thereby indirectly improving the sealing effect of the injection hole 110. Furthermore, when the abutment part 210 abuts against the insertion part 220, it can further seal the insertion part 220 and the injection hole 110, thereby improving the sealing performance of the sealing member 200 for the injection hole 110.

[0094] In this embodiment, the abutment portion 210 is circular, and the cross-section of the insertion portion 220 is circular. The diameter of the insertion portion 220 gradually decreases in the direction away from the abutment portion 210, so that when the insertion portion 220 is inserted into the injection hole 110, the insertion portion 220 can gradually abut against the inner wall of the injection hole 110, thereby indirectly improving the sealing effect between the insertion portion 220 and the injection hole 110.

[0095] In other embodiments, the shapes of the abutment portion 210 and the insertion portion 220 can be adapted as needed, for example, the abutment portion 210 can be set to a square shape.

[0096] The contact part 210 is a plastic plate, and the insertion part 220 is a rubber plug.

[0097] In this application, the plastic sheet has good chemical stability and mechanical strength, and can withstand various physical and chemical environments during battery use, ensuring the long-term stability of the sealing component 200; the rubber stopper has excellent elasticity, sealing and flexibility, and can closely fit the inner wall of the injection hole 110 to form a reliable seal, effectively preventing electrolyte leakage; this combination not only improves the sealing performance of the sealing component 200, but also enhances its adaptability to injection holes 110 of different shapes and sizes, ensuring that a good sealing effect can be maintained under various working conditions, thereby extending the battery's service life and improving its safety.

[0098] In other embodiments, the materials of the abutment portion 210 and the insertion portion 220 can also be adapted as needed, for example, the abutment portion 210 and the insertion portion 220 can be made of one of metal, composite and ceramic parts.

[0099] Combination Figures 1 to 4The cover plate 100 is provided with a receiving groove 130 along the circumference of the groove 120, and the receiving groove 130 is used to receive the circumferential edge of the seal 300.

[0100] In this application, by adopting the arrangement of the receiving groove 130, the edge of the sealing member 300 is moved into the receiving groove 130 and the sealing member 300 is fixed in the receiving groove 130 by welding, so that the sealing member 300 forms a sealing space 310 between the receiving groove 130 and the cover plate 100, preventing the sealing member 300 from protruding from the cover plate 100 and interfering with other electronic components in the battery pack, thereby indirectly reducing the space occupied by the sealing member 300.

[0101] In this embodiment, the cross-section of the receiving groove 130 is "L" shaped, and the edge of the sealing member 300 is configured to cooperate with the "L" shaped receiving groove 130.

[0102] In other embodiments, the shape of the receiving groove 130 can be adapted as needed, for example, the cross-section of the receiving groove 130 can be set to be arc-shaped, and the edge of the seal 300 can be matched with the arc-shaped receiving groove 130.

[0103] The advantages of the battery cover of this application will be illustrated below through examples and comparative examples.

[0104] Example 1: The helium-absorbing component 400 uses activated carbon sheets, which are formed by mixing activated carbon powder with an adhesive, coating, and then drying. The adhesive is epoxy resin, and the mass ratio of activated carbon powder to adhesive is 10:1. 50% of the particles in the activated carbon powder have a diameter of 10.0 ± 1.0 μm; the surface area of ​​the activated carbon powder is 900~1100 m². 2 / g, the thickness of the activated carbon sheet is 0.1±0.02mm;

[0105] The activated carbon sheet of this embodiment is placed in the sealed space 310 and fixed to the side of the abutment part 210 away from the insertion part 220. The sealing element 300 is welded to the receiving groove 130 of the cover plate 100 by spot welding. The welding parameters are adjusted to make a large leak weld. The leak rate is detected by back pressure helium detection. Ten samples of each type of welding are taken and the average value of the leak rate is taken.

[0106] Example 2: The helium-absorbing component 400 is attached to the back of the sealing component 300, and the rest is the same as in Example 1.

[0107] Example 3: The mass ratio of activated carbon powder to adhesive was changed to 20:1, and the rest was the same as in Example 1.

[0108] Example 4: The mass ratio of activated carbon powder to adhesive was changed to 1:1, and the rest was the same as in Example 1.

[0109] Example 5: The material of the helium absorber 400 was changed to a rubber sheet made of styrene-butadiene rubber, and the rest was the same as in Example 1.

[0110] Example 6: The helium-absorbing component 400 is attached to the back of the sealing cap, and the rest is the same as in Example 5.

[0111] Example 7: The material of the helium absorber 400 was changed to a silicone sheet made of foamed silicone, and the rest was the same as in Example 1.

[0112] Example 8: The material of the helium absorber 400 was changed to a foamed plastic sheet made of polyurethane foam, and the rest was the same as in Example 1.

[0113] Example 9: The mass ratio of activated carbon powder to adhesive was changed to 1:2, and the rest was the same as in Example 1.

[0114] Example 10: No helium-absorbing component 400, and the sealing component 200 is made of PPS. The rest is the same as in Example 1.

[0115] Example 11: No helium-absorbing component 400, and the sealing component 200 is made of PET. The rest is the same as in Example 1.

[0116] Helium detection method:

[0117] The weld seams in the above embodiments are inspected, and the settings for back pressure helium detection are as follows:

[0118] Helium compression station:

[0119] Evacuate for 2-4 seconds, set the pressure to 0-30 mbar; fill with helium at a pressure of 3100-3200 mbar, pressurize for 3 seconds, and hold for 5 seconds.

[0120] Helium testing station:

[0121] Transfer waiting time: 3 seconds; sample vacuuming time: 5 seconds; pressure setting: 0~0.9 mbar; leak detector test time: 3 seconds.

[0122] Weld defect evaluation criteria: Back pressure leakage rate ≤ 3.0E-06; judged as good welding, recorded as OK; otherwise, welding defective, recorded as NG;

[0123] The method for determining whether a leak can be detected stably and effectively is as follows: set the helium detection ratio γ = helium leak detection rate / standard leak rate value (the standard leak rate value is set to 3.0E-6). If γ ≥ 6-8, it means that it can be detected stably. If 1 < γ < 6, it means that it can be detected, but it may not be detected effectively every time.

[0124] The implementation status and test results of Examples 1 to 11 are shown in the table below:

[0125]

[0126] As can be seen from the data in the table above, the helium detection ratio γ of Examples 1 to 8 is greater than 1, and all of them can detect poorly welded cover plates 100. However, the helium detection ratio γ of Examples 1, 3, 5 and 6 is much larger than that of Examples 6 to 8, which means that Examples 1, 3, 5 and 6 can stably detect large leaks. As can be seen from Examples 1 and 2, the helium detection ratios of Structure 1 and Structure 2 are basically the same. The helium absorber sheet of Example 5 is a rubber sheet, which can also stably detect large leaks. Therefore, activated carbon sheet is preferred as helium absorber 400, and rubber sheet is preferred as helium absorber 400.

[0127] This application also provides a battery pack, including a housing and a battery cover plate of any of the above embodiments connected to the housing.

[0128] The specific structure of the battery cover has been described in detail in the above embodiments and will not be repeated here.

[0129] This application also provides an electrical device, including a device body and a battery pack of the above embodiments connected to the device body.

[0130] In this embodiment, the electrical equipment is a vehicle; in other embodiments, the electrical equipment may also be an energy storage system.

[0131] The electrical equipment provided in this application, by setting a battery cover, when it is necessary to seal the injection hole 110, is made by inserting a plastic plate and a rubber plug into the injection hole 110, so that the plastic plate abuts against the bottom wall of the tank 120. The helium-absorbing component 400 is fixed to the sealing component 300 or the plastic plate by the adhesive component 500. The sealing component 300 is fixed in the receiving tank 130 by welding, so that the rubber plug can seal the injection hole 110 and the sealing component 300 can seal the tank 120. When it is necessary to detect whether there is a leak between the sealing component 300 and the receiving tank 130, helium is first filled into the sealing space 310 along the leak position between the sealing component 300 and the receiving tank 130 by pressurizing. The helium-absorbing component 400 located in the sealing space 310 can absorb and store helium. When the cover is closed... When the cover plate 100 is placed in a vacuum environment for evacuation, the helium stored in the helium-absorbing component 400 can be slowly released. When the leakage between the seal 300 and the cover plate 100 is small, the helium can be continuously released and detected by the detection equipment, thus facilitating the determination of whether there is a leak when the leakage between the seal 300 and the cover plate 100 is small. When the leakage between the seal 300 and the cover plate 100 is large, even if the helium in the sealed space 310 is removed during the vacuuming process, some helium can still be continuously released through the helium-absorbing component 400 and detected by the detection equipment, thus facilitating the determination of whether there is a leak when the leakage between the seal 300 and the cover plate 100 is large. This reduces the phenomenon of the detection equipment missing the detection due to the complete removal of helium, and indirectly improves the accuracy of the sealing performance detection between the seal 300 and the cover plate 100.

[0132] Finally, it should be noted that other embodiments of this utility model will readily occur to those skilled in the art upon consideration of the specification and practice of the utility model disclosed herein. This utility model is intended to cover any variations, uses, or adaptations of this utility model that follow the general principles of this utility model and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this utility model is limited only by the appended claims.

Claims

1. A battery cover, characterized in that, include: Cover plate (100); A sealing element (200) is used to close the injection hole (110) on the cover plate (100); A sealing element (300) is connected to the cover plate (100), and a sealing space (310) is formed between the sealing element (300) and the cover plate (100), and the sealing element (200) is located in the sealing space (310); A helium-absorbing element (400) is disposed within the sealed space (310).

2. The battery cover according to claim 1, characterized in that, The sealing element (300) has a groove (330) on the side facing the sealing element (200), and the groove (330) is disposed opposite to the helium-absorbing element (400).

3. The battery cover according to claim 2, characterized in that, The distance between the bottom of the groove (330) and the sealing member (200) is greater than or equal to the thickness of the helium-absorbing member (400).

4. The battery cover according to claim 2, characterized in that, Along the thickness direction of the cover plate (100), the projection of the helium-absorbing element (400) on the cover plate (100) is located within the projection range of the groove (330) on the cover plate (100).

5. The battery cover according to claim 2, characterized in that, The helium-absorbing component (400) is connected to the bottom of the groove (330), or the helium-absorbing component (400) is connected to the sealing component (200) on the side near the groove (330).

6. The battery cover according to claim 5, characterized in that, It also includes an adhesive piece (500) connected to the helium-absorbing piece (400), and the helium-absorbing piece (400) is fixed to the groove (330) or the sealing piece (200) by means of the adhesive piece (500).

7. The battery cover according to any one of claims 1-6, characterized in that, The helium-absorbing element (400) is one of activated carbon sheet, rubber sheet, silicone sheet and foamed plastic sheet.

8. The battery cover according to claim 7, characterized in that, The helium-absorbing element (400) is an activated carbon sheet, which comprises activated carbon powder and an adhesive, wherein the mass ratio of the activated carbon powder to the adhesive is 1-20:

1.

9. The battery cover according to claim 8, characterized in that, At least some of the particles in the activated carbon powder have a diameter of 5μm-20μm.

10. The battery cover according to claim 8, characterized in that, The surface area of ​​the activated carbon powder is 500m² / g-1500m² / g.

11. The battery cover according to any one of claims 1-6, characterized in that, The cover plate (100) is provided with a groove (120), and the injection hole (110) is provided on the bottom wall of the groove (120). The groove (120) is used to accommodate the sealing member (200).

12. The battery cover according to claim 11, characterized in that, The sealing member (200) includes an abutment portion (210) and an insertion portion (220). The abutment portion (210) is connected to the insertion portion (220). The insertion portion (220) is used to insert into the injection hole (110) so that the abutment portion (210) abuts against the bottom wall of the tank (120). The tank (120) is used to accommodate the abutment portion (210).

13. The battery cover according to claim 12, characterized in that, The abutting part (210) is a plastic plate, and the insertion part (220) is a rubber plug.

14. The battery cover according to claim 11, characterized in that, The cover plate (100) is provided with a receiving groove (130) along the circumference of the groove (120), and the receiving groove (130) is used to receive the circumferential edge of the seal (300).

15. A battery pack, characterized in that, Includes a housing and a battery cover as described in any one of claims 1-14 connected to the housing.

16. An electrical appliance, characterized in that, The device includes the device body and the battery pack as described in claim 15, which is connected to the device body.

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