Sealing structure of battery liquid injection hole and battery

Abstract

The utility model discloses a sealing structure of a battery liquid injection hole and a battery, and the sealing structure of the battery liquid injection hole comprises a cover plate provided with a liquid injection hole; the sealing nail is arranged in the liquid injection hole and used for blocking the liquid injection hole, the sealing nail comprises a sealing piece and a fixing piece, the sealing piece wraps at least part of the fixing piece and is connected with the fixing piece, and a through hole penetrating through the fixing piece in the axial direction of the liquid injection hole is formed in the fixing piece. According to the sealing structure of the battery liquid injection hole, the sealing reliability of the liquid injection hole can be considered, the requirement for the internal pressure sampling inspection function in the battery manufacturing process is met, and the safety of a battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a sealing structure for a battery liquid injection hole and a battery. Background Art

[0002] In the related art, a battery is generally provided with a liquid injection hole for injecting liquid into the battery, and a sealing nail is provided at the liquid injection hole to seal the liquid injection hole. However, the sealing effect of the existing sealing nail at the liquid injection hole is poor and it is not convenient to detect the internal pressure of the battery by equipment. Summary of the Utility Model

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. For this purpose, the utility model provides a sealing structure for a battery liquid injection hole, which can take into account the sealing reliability at the liquid injection hole and meet the requirement of the internal pressure inspection function during the battery manufacturing process, and is beneficial to improving the safety of the battery.

[0004] Another object of the utility model is to provide a battery having the above-mentioned sealing structure for a battery liquid injection hole.

[0005] According to the sealing structure for a battery liquid injection hole of the embodiment of the utility model, it includes: a cover plate, and the cover plate is provided with a liquid injection hole; a sealing nail, the sealing nail is arranged in the liquid injection hole to block the liquid injection hole, the sealing nail includes a sealing member and a fixing member, the sealing member covers at least part of the fixing member and is connected with the fixing member, and the fixing member is provided with a through hole penetrating the fixing member along the axial direction of the liquid injection hole.

[0006] According to the sealing structure for a battery liquid injection hole of the embodiment of the utility model, by covering at least part of the fixing member with the sealing member of the sealing nail and connecting with the fixing member, the sealing member is used to seal the liquid injection hole, and the fixing member can improve the structural strength of the sealing nail, so as to ensure the sealing reliability of the liquid injection hole on the cover plate. In addition, the fixing member of the sealing nail is provided with a through hole penetrating the fixing member along the axial direction of the liquid injection hole, which can enable the internal pressure testing equipment to pass through the through hole on the fixing member and pierce the sealing member to extend into the battery interior to measure the internal pressure of the battery, meeting the requirement of the internal pressure inspection function during the manufacturing process.

[0007] In some embodiments of the utility model, the diameter of the through hole is d3, and it satisfies: d3≥0.5mm.

[0008] In some embodiments of the utility model, the sealing member includes: a first sealing member, the first sealing member is sleeved outside the fixing member and is sealingly connected with the liquid injection hole; a second sealing member, the second sealing member is arranged on the side of the fixing member facing the battery interior and is connected with the first sealing member.

[0009] In some embodiments of the present utility model, a protrusion is provided on the outer peripheral wall of the fixing member, and a groove cooperating with the protrusion is provided on the inner peripheral wall of the first sealing member.

[0010] In some embodiments of the present utility model, the protrusion is an annular shape extending along the circumferential direction of the fixing member; and / or, the protrusion is located at one end of the fixing member facing the inside of the battery; and / or, in the direction from one end of the first sealing member close to the second sealing member to the end away from the second sealing member, the height of the protrusion gradually increases.

[0011] In some embodiments of the present utility model, the liquid injection hole includes a first hole section and a second hole section. One end of the second hole section is communicated with one end of the first hole section and is located on the side of the first hole section facing the inside of the battery. The diameter of the second hole section is smaller than the diameter of the first hole section. The fixing member includes: a first fixing section located in the first hole section, and the diameter of the first fixing section is larger than the inner diameter of the second hole section; a second fixing section connected to the side of the first fixing section facing the second hole section and at least partially located in the second hole section, and the diameter of the second fixing section is smaller than the diameter of the first fixing section. The first sealing member is sleeved outside the second fixing section and is sealingly connected to the second hole section.

[0012] In some embodiments of the present utility model, the diameter of the second fixing section is d2, the outer diameter of the first sealing member is d, and it satisfies: 1 / 3 ≤ d2 / d ≤ 1 / 2.

[0013] In some embodiments of the present utility model, the diameter of the through hole is d3, the inner diameter of the second hole section is d1, the outer diameter of the first sealing member is d, and it satisfies: 5% ≤ ((d - d3) / 2) / ((d1 - d3) / 2) ≤ 50%.

[0014] In some embodiments of the present utility model, the length of the second hole section is H1, and along the axial direction of the liquid injection hole, the effective sealing length between the first sealing member and the second hole section is H, and it satisfies: H1 - H = 0.3 - 1.2 mm.

[0015] In some embodiments of the present utility model, the effective sealing length between the first sealing member and the second hole section is H, and it satisfies: H ≥ 1 mm.

[0016] In some embodiments of the present utility model, the first sealing member includes a sealing section and a guiding section. The two ends of the guiding section are respectively connected to the sealing section and the second sealing member. In the direction from the sealing section to the guiding section, the outer diameter of the sealing section remains unchanged, and the outer diameter of the guiding section gradually decreases.

[0017] In some embodiments of the present utility model, the guiding section is entirely located outside the second hole section.

[0018] In some embodiments of the present utility model, the length by which the sealing section extends beyond the second hole section is H2, and it satisfies: H2 ≥ 0.5 mm.

[0019] In some embodiments of the present utility model, one end of the sealing section facing away from the guiding section is in contact with or spaced apart from the first fixing section. The length of the second hole section is H1, and the effective sealing length of the first sealing member and the second hole section is H, and it satisfies: h1 ≥ 1.5 + (H1 - H).

[0020] In some embodiments of the present utility model, the diameter of the first fixing section is D1, and the inner diameter of the second hole section is d1, and it satisfies: D1 - d1 ≥ 1 mm.

[0021] In some embodiments of the present utility model, along the axis direction of the liquid injection hole, the thickness of the second sealing member is t, and it satisfies: t ≥ 0.3 mm.

[0022] In some embodiments of the present utility model, the sealing member is an EPDM member or an FKM member; and / or, the fixing member is a PP member, a PET member or a PPS member.

[0023] In some embodiments of the present utility model, the sealing structure of the battery liquid injection hole further includes: a sealing cover, which is arranged on the side of the sealing nail facing away from the inside of the battery and is connected to the cover plate, and is used for sealing and plugging the liquid injection hole.

[0024] In some embodiments of the present utility model, the surface of the sealing cover facing away from the sealing nail is flush with the surface of the cover plate facing away from the inside of the battery; or, the sealing cover protrudes from the surface of the cover plate facing away from the inside of the battery, and the protruding height of the sealing cover is less than or equal to 0.5 mm.

[0025] The battery according to the embodiment of the present utility model includes: the above-mentioned sealing structure of the battery liquid injection hole.

[0026] The battery according to the embodiment of the present utility model, by providing the above-mentioned sealing structure of the battery liquid injection hole, wraps at least part of the fixing member with the sealing member of the sealing nail and is connected to the fixing member. The sealing member is used for sealing the liquid injection hole, and the fixing member can improve the structural strength of the sealing nail, thereby ensuring the sealing reliability of the liquid injection hole on the cover plate. In addition, there is a through hole penetrating the fixing member along the axial direction of the liquid injection hole on the fixing member of the sealing nail, which can enable the internal pressure testing device to pass through the through hole on the fixing member and pierce the sealing member to extend into the battery interior to measure the internal pressure of the battery, meeting the requirements of the process for sampling and inspecting the internal pressure function.

[0027] Additional aspects and advantages of the present utility model will be given in part in the following description, become apparent in part from the following description, or be understood through the practice of the present utility model. Description of the Drawings

[0028] The above and / or additional aspects and advantages of the present utility model will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, where:

[0029] Figure 1 is an exploded view of the sealing structure of the battery liquid injection hole according to an embodiment of the present utility model;

[0030] Figure 2 is a cross-sectional view of the sealing structure of the battery liquid injection hole according to an embodiment of the present utility model;

[0031] Figure 3 is a cross-sectional view of the sealing structure of the battery liquid injection hole according to an embodiment of the present utility model, which shows the dimensions;

[0032] Figure 4 is a cross-sectional view of the sealing nail of the sealing structure of the battery liquid injection hole according to an embodiment of the present utility model;

[0033] Figure 5 is a cross-sectional view of the sealing nail of the sealing structure of the battery liquid injection hole according to an embodiment of the present utility model, which shows the dimensions.

[0034] Figure 6 is a perspective view of the battery according to an embodiment of the present utility model;

[0035] Figure 7 is Figure 6 an enlarged view of part A in

[0036] Reference Numerals:

[0037] 100, sealing structure of the battery liquid injection hole;

[0038] 1, cover plate; 11, liquid injection hole; 111, first hole section; 112, second hole section;

[0039] 2, sealing nail; 21, seal; 211, first seal; 2111, sealing section; 2112, guiding section; 2113, groove; 212, second seal; 22, fixing member; 221, first fixing section; 222, second fixing section; 223, through hole; 224, protrusion;

[0040] 3, sealing cover;

[0041] 4, insulator;

[0042] 200, battery; 201, housing. Detailed Description of the Embodiments

[0043] Embodiments of the present utility model will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation to the present utility model.

[0044] The sealing structure 100 of the battery liquid injection hole according to an embodiment of the present utility model will be described below with reference to the accompanying drawings.

[0045] As Figure 1 and Figure 2 shown, the sealing structure 100 of the battery liquid injection hole according to an embodiment of the present utility model includes a cover plate 1 and a sealing nail 2.

[0046] Specifically, as Figure 1 - Figure 2 shown, the cover plate 1 is provided with a liquid injection hole 11, and the sealing nail 2 is arranged in the liquid injection hole 11 for plugging the liquid injection hole 11 to ensure the sealing reliability of the liquid injection hole 11. The sealing nail 2 includes a sealing member 21 and a fixing member 22. The sealing member 21 covers at least part of the fixing member 22 and is connected to the fixing member 22, so that the sealing member 21 and the fixing member 22 can be connected as a whole.

[0047] Among them, the hardness and structural strength of the fixing member 22 are greater than those of the sealing member 21. The sealing member 21 can cooperate with the inner peripheral wall of the liquid injection hole 11 to realize the plugging of the liquid injection hole 11. The fixing member 22 is arranged inside the sealing member 21, and the fixing member 22 can enhance the structural strength of the whole sealing nail 2, thereby improving the sealing reliability of the sealing nail 2 for the liquid injection hole 11. In addition, the structure of the sealing nail 2 is simple, which is convenient for the cooperation and installation of the sealing member 21 and the fixing member 22.

[0048] In addition, as Figure 1 - Figure 2 shown, the fixing member 22 is provided with a through hole 223 penetrating the fixing member 22 along the axial direction of the liquid injection hole 11. At least one end of the fixing member 22 along the axial direction of the liquid injection hole 11 is covered with the sealing member 21. Thus, the through hole 223 can be sealed by the sealing member 21 to ensure the sealing reliability of the sealing nail 2 for the liquid injection hole 11. The internal pressure testing device can pass through the through hole 223 on the fixing member 22 and pierce the sealing member 21 to extend into the interior of the battery 200 for testing the internal pressure of the battery 200, meeting the requirements of the process sampling internal pressure function.

[0049] In addition, the sealing member 21 located at one axial end of the fixing member 22 is closely attached to the fixing member 22, which can relatively reduce the length of the sealing nail 2 along the axis direction of the liquid injection hole 11, facilitating the internal pressure testing device to pass through the through hole 223 on the fixing member 22 and pierce the sealing member 21 to extend into the interior of the battery 200.

[0050] According to the sealing structure 100 of the battery injection hole of the embodiment of the utility model, the sealing member 21 of the sealing nail 2 covers at least a part of the fixing member 22 and is connected to the fixing member 22, the sealing member 21 is used to seal the injection hole 11, and the fixing member 22 can improve the structural strength of the sealing nail 2, thereby ensuring the sealing reliability of the injection hole 11 on the cover plate 1. In addition, the fixing member 22 of the sealing nail 2 has a through hole 223 that penetrates the fixing member 22 along the axial direction of the injection hole 11, so that the internal pressure test equipment can pass through the through hole 223 on the fixing member 22 and pierce the sealing member 21 to reach into the battery 200 to measure the internal pressure of the battery 200, thereby meeting the requirements of the process random inspection internal pressure function.

[0051] In some embodiments of the present invention, Figure 3 As shown, the diameter of the through hole 223 is d3, and satisfies: d3 ≥ 0.5 mm. This ensures that the internal pressure test equipment can pass through the through hole 223 on the fixing member 22 and pierce the sealing member 21 to enter the battery 200 for testing the internal pressure of the battery 200, meeting the requirements of the internal pressure sampling function of the process.

[0052] In some embodiments of the present invention, Figure 2 and Figure 4 As shown, the sealing member 21 includes: a first sealing member 211 and a second sealing member 212. The first sealing member 211 is sleeved outside the fixing member 22 and is sealed and connected to the injection hole 11, and the second sealing member 212 is arranged on the side of the fixing member 22 facing the inside of the battery 200 and is connected to the first sealing member 211. The first sealing member 211 can seal the gap between the sealing nail 2 and the inner peripheral wall of the injection hole 11, and the second sealing member 212 can block the end of the through hole 223 facing the inside of the battery 200, and can seal the through hole 223, so that the sealing of the injection hole 11 is achieved through the entire sealing nail 2.

[0053] In addition, a second sealing member 212 is provided at one end of the fixing member 22 close to the inside of the battery 200 along the axial direction of the injection hole 11, which can ensure the insulation of the internal environment of the battery 200. In addition, the second sealing member 212 and the end of the fixing member 22 close to the inside of the battery 200 are in contact with each other, and the side of the fixing member 22 facing away from the second sealing member 212 is exposed, that is, it is not covered with the sealing member 21, and the side of the through hole 223 of the fixing member 22 facing away from the second sealing member 212 is open, and the internal pressure detection equipment can enter the through hole 223 of the fixing member 22 of the sealing nail 2 through the injection hole 11, and pierce the second sealing member 212, and probe into the inside of the battery 200, which is used to detect the internal pressure function of the battery 200.

[0054] In some embodiments of the present invention, Figure 1 and Figure 2As shown, the outer peripheral wall of the fixing member 22 has a protrusion 224, and the inner peripheral wall of the first sealing member 211 has a groove 2113 that cooperates with the protrusion 224, so that the sealing member 21 can be fixedly combined with the fixing member 22 as a whole, increasing the reliability of the connection between the sealing member 21 and the fixing member 22 and preventing the fixing member 22 from coming out of the sealing member 21.

[0055] In some embodiments of the present utility model, as Figure 1 shown, the protrusion 224 is an annular shape extending along the circumferential direction of the fixing member 22, and the groove 2113 on the inner peripheral wall of the first sealing member 211 is also annular, cooperating with the protrusion 224 on the outer peripheral wall of the fixing member 22. Thereby, the reliability of the fixation between the sealing member 21 and the fixing member 22 can be further increased, avoiding the fixing member 22 and the sealing member 21 from separating from each other, and thus ensuring the reliability of the sealing of the liquid injection hole 11 by the sealing nail 2.

[0056] In some embodiments of the present utility model, as Figure 1 shown, the protrusion 224 is located at one end of the fixing member 22 facing the inside of the battery 200, cooperating with the groove 2113 on the inner peripheral wall of the first sealing member 211, which can prevent the sealing member 21 from detaching from the fixing member 22 and entering the inside of the battery 200.

[0057] In some embodiments of the present utility model, as Figure 1 shown, in the direction from one end of the first sealing member 211 close to the second sealing member 212 to the end away from the second sealing member 212, the height of the protrusion 224 gradually increases, making one end of the fixing member 22 close to the second sealing member 212 conical, which plays a guiding role and facilitates the assembly of the fixing member 22 and the sealing member 21.

[0058] In some embodiments of the present utility model, as Figure 1 and Figure 7 shown, the liquid injection hole 11 includes a first hole section 111 and a second hole section 112. One end of the second hole section 112 is communicated with one end of the first hole section 111 and is located on the side of the first hole section 111 facing the inside of the battery 200. The first hole section 111 and the second hole section 112 are concentrically arranged, and the diameter of the second hole section 112 is smaller than that of the first hole section 111, making the liquid injection hole 11 in a stepped shape, which is beneficial to the cooperative installation of the liquid injection hole 11 and the sealing nail 2.

[0059] In some embodiments of the present utility model, as Figure 1 and Figure 2As shown in the figure, the fixing member 22 includes a first fixing section 221 and a second fixing section 222. The first fixing section 221 is located within the first hole section 111. The diameter of the first fixing section 221 is greater than the inner diameter of the second hole section 112. The end face of the first fixing section 221 facing the second fixing section 222 can abut against the stepped surface between the first hole section 111 and the second hole section 112, thereby restricting the sealing nail 2 from slipping axially into the battery 200 along the liquid injection hole 11, playing a limiting role and preventing the fixing member 22 from slipping into the battery 200. The second fixing section 222 is connected to the side of the first fixing section 221 facing the second hole section 112 and is at least partially located within the second hole section 112. The diameter of the second fixing section 222 is smaller than the diameter of the first fixing section 221. The first sealing member 211 is sleeved outside the second fixing section 222 and is sealingly connected to the second hole section 112. Within the second hole section 112, the first sealing member 211 is closely and fittingly connected to the second fixing section 222, ensuring the airtightness of the sealing structure 100 of the battery liquid injection hole.

[0060] In some embodiments of the present utility model, as Figure 3 shown, the diameter of the second fixing section 222 is d2, and the outer diameter of the first sealing member 211 is d, and it satisfies: 1 / 3 ≤ d2 / d ≤ 1 / 2. If d2 / d < 1 / 3, on the premise of the same diameter of the sealing nail 2, the diameter of the second fixing section 222 of the sealing nail 2 is too small, reducing the structural strength of the fixing member 22 and being unfavorable for arranging the through hole 223 within the fixing member 22. If d2 / d > 1 / 2, on the premise of the same diameter of the sealing nail 2, the thickness of the first sealing member 211 is too small, being unfavorable for the sealing of the liquid injection hole 11 of the battery 200. If 1 / 3 ≤ d2 / d ≤ 1 / 2 is satisfied, the airtightness and structural strength of the sealing nail 2 can be taken into account, ensuring the excellent manufacturability and performance of each component.

[0061] In some embodiments of the present utility model, as Figure 3 shown, the diameter of the through hole 223 is d3, the inner diameter of the second hole section 112 is d1, and the outer diameter of the first sealing member 211 is d, and it satisfies: 5% ≤ ((d - d3) / 2) / ((d1 - d3) / 2) ≤ 50%. ((d - d3) / 2) / ((d1 - d3) / 2) is the actual compression amount of the first sealing member 211 of the sealing nail 2. If ((d - d3) / 2) / ((d1 - d3) / 2) < 5%, the actual compression amount of the first sealing member 211 is too small, being unfavorable for the sealing of the liquid injection hole 11 of the battery 200. If ((d - d3) / 2) / ((d1 - d3) / 2) > 50%, the compression amount of the first sealing member 211 is too large, and it is difficult to insert the sealing nail 2 into the liquid injection hole 11 on the cover plate 1, being unfavorable for the assembly of the sealing structure 100 of the battery liquid injection hole. If 5% ≤ ((d - d3) / 2) / ((d1 - d3) / 2) ≤ 50% is satisfied, the airtightness and assemblability of the rubber nail can be ensured.

[0062] In some embodiments of the present utility model, as Figure 3 shown, the length of the second hole section 112 is H1. Along the axial direction of the liquid injection hole 11, the effective sealing length of the first seal 211 and the second hole section 112 is H, and it satisfies: H1 - H = 0.3 to 1.2 mm. If H1 - H < 0.3 mm, the fillet size at the connection between the second hole section 112 and the first hole section 111 is too small, which is not conducive to the assembly and cooperation between the seal 21 and the liquid injection hole 11 of the cover plate 1. If H1 - H > 1.2 mm, on the premise that the length of the second hole section 112 remains unchanged, the effective sealing length of the second hole section 112 is too small, which is not conducive to the sealing of the liquid injection hole 11 of the battery 200. If H1 - H = 0.3 to 1.2 mm is satisfied, the sealing performance and assemblability of the sealing nail 2 can be taken into account, and the process yield of the sealing nail 2 can be ensured.

[0063] In some embodiments of the present utility model, as Figure 3 shown, the effective sealing length of the first seal 211 and the second hole section 112 is H, and it satisfies: H ≥ 1 mm, ensuring the sealing reliability of the rubber nail. Moreover, the larger the effective sealing length H is, the better the sealing effect of the rubber nail is.

[0064] In some embodiments of the present utility model, as Figure 1 and Figure 2 shown, the first seal 211 includes a sealing section 2111 and a guiding section 2112. The two ends of the guiding section 2112 are respectively connected to the sealing section 2111 and the second seal 212. In the direction from the sealing section 2111 to the guiding section 2112, the outer diameter of the sealing section 2111 remains unchanged, and the outer diameter of the guiding section 2112 gradually decreases, making the guiding section 2112 of the first seal 211 conical, which can play a guiding role and facilitate the overall insertion of the sealing nail 2 into the liquid injection hole 11 of the cover plate 1.

[0065] In some embodiments of the present utility model, as Figure 2 shown, the guiding section 2112 is entirely located outside the second hole section 112, ensuring that the sealing performance of the sealing nail 2 in the area of the second hole section 112 is not affected by the guiding section 2112 with a gradually decreasing outer diameter, and guaranteeing the sealing reliability between the sealing nail 2 and the liquid injection hole 11.

[0066] In some embodiments of the present utility model, as Figure 3As shown, the length of the sealing section 2111 that exceeds the second hole section 112 is H2, and satisfies: H2 ≥ 0.5 mm, so that the sealing section 2111 partially exceeds the second hole section 112, which can ensure that the sealing performance of the sealing nail 2 in the second hole section 112 area is not affected by the guide section 2112 whose outer diameter gradually decreases. In addition, after the sealing nail 2 is inserted into the injection hole 11, the portion of the sealing section 2111 that exceeds the second hole section 112 will expand and deform to form a barb-like structure, which can prevent the sealing nail 2 from slipping in the injection hole 11, play a role of limiting, and prevent the sealing nail 2 from falling out of the injection hole 11.

[0067] In some embodiments of the present invention, Figure 3 and Figure 5 As shown, the end of the sealing section 2111 away from the guide section 2112 is fitted or spaced from the first fixing section 221, that is, the length h1 of the sealing section 2111 on the sealing member 21, and the distance between the end of the sealing section 2111 close to the guide section 2112 and the first fixing section 221 is h, satisfying h≥h1. It can be understood that a certain gap can be left between the first sealing member 211 and the first fixing section 221, or the first sealing member 211 and the first fixing section 221 are tightly fitted. If a certain gap can be left between the first sealing member 211 and the first fixing section 221, that is, h>h1, when the fixing member 22 and the sealing member 21 are assembled, a certain movable space is left between the first fixing section 221 and the sealing section 2111, so as to facilitate the matching assembly of the fixing member 22 and the sealing member 21. If the end of the sealing section 2111 away from the guide section 2112 is fitted with the first fixing section 221, the integrity of the sealing nail 2 will be better.

[0068] In addition, the length of the second hole section 112 is H1, the effective sealing length of the first seal 211 and the second hole section 112 is H, and they satisfy: h1 ≥ 1.5 + (H1-H), where 1.5 is the minimum value of the sum of the effective sealing length H of the second hole section 112 and the length H2 of the sealing section 2111 beyond the second hole section 112, and H1-H is the guide R angle on the cover plate 1. The length h1 of the sealing section 2111 on the seal 21 satisfies h1 ≥ 1.5 + (H1-H), ensuring the sealing performance of the sealing structure 100 of the battery filling hole. Figure 3 and Figure 5 As shown, if h1 is too small, the effective sealing length of the first sealing member 211 and the second hole section 112 will also be reduced, which is not conducive to the sealing performance of the sealing nail 2 on the injection hole 11.

[0069] In some embodiments of the present invention, Figure 3As shown, the diameter of the first fixing section 221 is D1, and the inner diameter of the second hole section 112 is d1, and the following condition is satisfied: D1 - d1 ≥ 1 mm. The diameter of the first fixing section 221 is greater than the inner diameter of the second hole section 112. After the sealing nail 2 is inserted into the liquid injection hole 11, the second hole section 112 restricts the sealing nail 2 from slipping axially into the battery 200 along the liquid injection hole 11, playing a limiting role and preventing the fixing member 22 from slipping into the battery 200. In addition, the first fixing section 221 is the main stress-bearing part when the sealing nail 2 is inserted into the liquid injection hole 11. If D1 - d1 is too small, the structural strength of the fixing member 22 will be reduced, and it may not be able to play a limiting role.

[0070] In some embodiments of the present invention, as Figure 5 shown, along the axis direction of the liquid injection hole 11, the thickness of the second sealing member 212 is t, and the following condition is satisfied: t ≥ 0.3 mm. The second sealing member 212 is provided with a certain thickness, which can ensure insulation from the inside of the battery 200 and guarantee the reliability of the insulation performance of the sealing structure 100 of the battery liquid injection hole.

[0071] In some embodiments of the present invention, the sealing member 21 can be an EPDM (Ethylene Propylene Diene Monomer) member or an FKM (Fluoroelastomer) member. The EPDM member and the FKM member have good insulation and aging resistance, ensuring the sealing reliability of the sealing structure 100 of the battery liquid injection hole. Of course, other modified materials based on this can also be used for the sealing member 21.

[0072] In some embodiments of the present invention, the fixing member 22 can be a PP (Polypropylene) member, a PET (Polyethylene Terephthalate) member or a PPS (Phenylenesulfide) member. The PP member, the PET member and the PPS member have good stability and structural strength, which can improve the overall structural strength of the sealing member 21. Of course, other rigid plastic materials with strength and injectability equivalent to these several materials can also be used for the fixing member 22.

[0073] In some embodiments of the present invention, as Figure 1 and Figure 2As shown, the sealing structure 100 of the battery liquid injection hole further includes a sealing cover 3. The sealing cover 3 is disposed on the side of the sealing nail 2 facing away from the inside of the battery 200 and is connected to the cover plate 1, for sealing and plugging the liquid injection hole 11, improving the reliability of the sealing of the liquid injection hole 11. At the same time, the sealing cover 3 also has a function of protecting against foreign objects. In addition, a cavity space is left between the sealing cover 3 and the sealing nail 2. When the side of the fixing member 22 facing away from the inside of the battery 200 is exposed, that is, when it is not covered by the sealing member 21, the cavity space communicates with the through hole 223 of the fixing member 22, which can increase the cavity space inside the sealing structure 100 of the battery liquid injection hole. The larger the volume of the cavity inside the sealing structure 100 of the battery liquid injection hole, the higher the accuracy of the airtightness detection. Therefore, the sealing structure 100 of the battery liquid injection hole of the present application not only ensures the sealing reliability of the liquid injection hole 11, but also is beneficial to improving the accuracy of the airtightness detection.

[0074] In some embodiments of the present invention, the surface of the sealing cover 3 facing away from the sealing nail 2 and the surface of the cover plate 1 facing away from the inside of the battery 200 are flush, or the sealing cover 3 protrudes from the surface of the cover plate 1 on the side facing away from the inside of the battery 200, and the height of the protrusion 224 of the sealing cover 3 is less than or equal to 0.5 mm. When the cover plate 1 is wrapped with a blue film, normal film wrapping can be carried out without opening a hole in the blue film of the cover plate 1, ensuring the integrity and insulation performance of the blue film. When water or other liquid leakage occurs during the wrapping of the battery 200, insulation failure or short circuit at the sealing cover 3 of the liquid injection hole 11 can be avoided.

[0075] In some embodiments of the present invention, as Figure 2 shown, the liquid injection hole 11 further includes a third hole section. The third hole section is located on the side of the first hole section 111 facing away from the second hole section 112. The inner diameter of the third hole section is larger than the inner diameter of the first hole section 111. At least a part of the sealing cover 3 is located in the third hole section and is connected to the inner wall of the third hole section, such as by welding connection, which can better make the surface of the sealing cover 3 flush with the surface of the cover plate 1 facing away from the inside of the battery 200 or the height of the sealing cover 3 protruding from the surface of the cover plate 1 on the side facing away from the inside of the battery 200 is smaller. Normal film wrapping can be carried out without opening a hole in the blue film of the cover plate 1, ensuring the integrity of the blue film and the insulation performance at the sealing cover 3.

[0076] Next, according to Figure 1 、 Figure 6 and Figure 7 describe the battery 200 according to the embodiments of the present invention.

[0077] The battery 200 according to the embodiments of the present invention includes the above-mentioned sealing structure 100 of the battery liquid injection hole, as Figure 1 、 Figure 6 and Figure 7As shown, the battery 200 includes a housing 201 with at least one open end in the axial direction. A cover plate 1 is provided at the open end of the housing 201 to seal the open end of the housing 201. The cover plate 1 has a liquid injection hole 11, and a sealing nail 2 is disposed in the liquid injection hole 11 to seal the liquid injection hole 11, ensuring the sealing reliability of the liquid injection hole 11.

[0078] For the battery 200 according to an embodiment of the present invention, by providing the above-mentioned sealing structure 100 for the battery liquid injection hole, the sealing member 21 of the sealing nail 2 covers and is at least partially fixed to the fixing member 22 and is connected to the fixing member 22. The sealing member 21 is used to seal the liquid injection hole 11, and the fixing member 22 can improve the structural strength of the sealing nail 2, thereby ensuring the sealing reliability of the liquid injection hole 11 on the cover plate 1. In addition, the fixing member 22 of the sealing nail 2 has a through hole 223 penetrating the fixing member 22 in the axial direction of the liquid injection hole 11, which enables the internal pressure testing device to pass through the through hole 223 on the fixing member 22 and pierce the sealing member 21 to extend into the battery 200 to measure the internal pressure of the battery 200, meeting the requirements of the process sampling internal pressure function.

[0079] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0080] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "mounted", "connected", and "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0081] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc., mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0082] Although the embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present utility model, and the scope of the present utility model is defined by the claims and their equivalents.

Claims

1. A sealing structure for a battery liquid filling hole, characterized in that: include: A cover plate (1), wherein the cover plate (1) has a liquid injection hole (11); A sealing nail (2), the sealing nail (2) being arranged in the injection hole (11) for sealing the injection hole (11), the sealing nail (2) comprising a sealing member (21) and a fixing member (22), the sealing member (21) covering at least a portion of the fixing member (22) and being connected to the fixing member (22), the fixing member (22) having a through hole (223) penetrating the fixing member (22) along the axial direction of the injection hole (11).

2. The sealing structure of the battery liquid filling hole according to claim 1, characterized in that: The diameter of the through hole (223) is d3, and satisfies: d3≥0.5 mm.

3. The sealing structure of the battery liquid filling hole according to claim 1, characterized in that: The sealing member (21) comprises: A first sealing member (211), the first sealing member (211) being sleeved outside the fixing member (22) and being sealedly connected to the liquid injection hole (11); A second sealing member (212), the second sealing member (212) is arranged on a side of the fixing member (22) facing the inside of the battery (200) and is connected to the first sealing member (211).

4. The sealing structure of the battery liquid filling hole according to claim 3, characterized in that: The fixing member (22) has a protrusion (224) on its outer peripheral wall, and the first sealing member (211) has a groove (2113) on its inner peripheral wall that matches the protrusion (224).

5. The sealing structure of the battery liquid filling hole according to claim 4, characterized in that: The protrusion (224) is annular and extends in the circumferential direction of the fixing member (22); and / or, the protrusion (224) is located at an end of the fixing member (22) facing the inside of the battery (200); And / or, in a direction from an end of the first sealing member (211) close to the second sealing member (212) to an end away from the second sealing member (212), the height of the protrusion (224) gradually increases.

6. The sealing structure of the battery liquid filling hole according to claim 3, characterized in that: The injection hole (11) comprises a first hole segment (111) and a second hole segment (112), one end of the second hole segment (112) is connected to one end of the first hole segment (111) and is located on a side of the first hole segment (111) facing the inside of the battery (200), the diameter of the second hole segment (112) is smaller than the diameter of the first hole segment (111), and the fixing member (22) comprises: a first fixing section (221), the first fixing section (221) being located in the first hole section (111), the diameter of the first fixing section (221) being greater than the inner diameter of the second hole section (112); A second fixing section (222), the second fixing section (222) is connected to a side of the first fixing section (221) facing the second hole section (112) and is at least partially located in the second hole section (112), the diameter of the second fixing section (222) is smaller than the diameter of the first fixing section (221), and the first sealing member (211) is sleeved outside the second fixing section (222) and is sealingly connected to the second hole section (112).

7. The sealing structure of the battery liquid filling hole according to claim 6, characterized in that: The diameter of the second fixing section (222) is d2, the outer diameter of the first sealing element (211) is d, and the following relationship is satisfied: 1 / 3≤d2 / d≤1 / 2.

8. The sealing structure of the battery liquid filling hole according to claim 6, characterized in that: The diameter of the through hole (223) is d3, the inner diameter of the second hole section (112) is d1, the outer diameter of the first sealing member (211) is d, and the following conditions are satisfied: 5%≤((d-d3) / 2) / ((d1-d3) / 2)≤50%.

9. The sealing structure of the battery liquid filling hole according to claim 6, characterized in that: The length of the second hole section (112) is H1, and along the axial direction of the injection hole (11), the effective sealing length of the first sealing member (211) and the second hole section (112) is H, and satisfies: H1-H=0.3-1.2 mm.

10. The sealing structure of the battery liquid filling hole according to claim 6, characterized in that: The effective sealing length of the first sealing member (211) and the second hole section (112) is H, and satisfies: H≥1 mm.

11. The sealing structure of the battery liquid filling hole according to claim 6, characterized in that: The first sealing member (211) comprises a sealing section (2111) and a guiding section (2112); two ends of the guiding section (2112) are respectively connected to the sealing section (2111) and the second sealing member (212); in a direction from the sealing section (2111) to the guiding section (2112), the outer diameter of the sealing section (2111) remains unchanged, while the outer diameter of the guiding section (2112) gradually decreases.

12. The sealing structure of the battery liquid filling hole according to claim 11, characterized in that: The guide section (2112) is entirely located outside the second hole section (112).

13. The sealing structure of the battery liquid filling hole according to claim 12, characterized in that: The length of the sealing section (2111) exceeding the second hole section (112) is H2, and satisfies: H2≥0.5 mm.

14. The sealing structure of the battery liquid filling hole according to claim 11, characterized in that: One end of the sealing section (2111) facing away from the guiding section (2112) is in contact with or spaced apart from the first fixing section (221), the length of the second hole section (112) is H1, the effective sealing length of the first sealing member (211) and the second hole section (112) is H, and the following condition is satisfied: h1≥1.5+(H1-H).

15. The sealing structure of the battery liquid filling hole according to claim 6, characterized in that: The diameter of the first fixing section (221) is D1, the inner diameter of the second hole section (112) is d1, and the following condition is satisfied: D1-d1≥1 mm.

16. The sealing structure of the battery liquid filling hole according to claim 3, characterized in that: Along the axial direction of the liquid injection hole (11), the thickness of the second sealing member (212) is t, and satisfies: t≥0.3 mm.

17. The sealing structure of the battery liquid filling hole according to claim 1, characterized in that: The sealing member (21) is an EPDM member or a FKM member; And / or, the fixing part (22) is a PP part, a PET part or a PPS part.

18. The sealing structure of the battery liquid filling hole according to claim 1, characterized in that: Also includes: A sealing cover (3) is arranged on a side of the sealing pin (2) facing away from the interior of the battery (200) and is connected to the cover plate (1), and is used to seal and block the liquid injection hole (11).

19. The sealing structure of the battery liquid filling hole according to claim 18, characterized in that: The surface of the sealing cover (3) facing away from the sealing pin (2) is flush with the surface of the cover plate (1) facing away from the interior of the battery (200); Alternatively, the sealing cover (3) protrudes from a side surface of the cover plate (1) that is away from the interior of the battery (200), and a height of the protrusion (224) of the sealing cover (3) is less than or equal to 0.5 mm.

20. A battery, characterized in that: A sealing structure (100) for a battery liquid filling hole according to any one of claims 1 to 19.

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