Cover plate assembly and battery

Abstract

The utility model provides a cover plate assembly and a battery, and relates to the technical field of new energy. The cover plate assembly provided by the utility model comprises a substrate with a mounting hole; an electrode terminal, a fixing sleeve and a first sealing element, the fixing sleeve sleeves the electrode terminal and is fixedly connected with the substrate, the electrode terminal comprises a main body part and an extension part which are connected with each other, at least part of the fixing sleeve wraps the extension part, and the main body part is hermetically connected to the mounting hole through the first sealing element; the connecting piece is fixedly connected to the main body part, and the supporting piece is connected between the substrate and the connecting piece. The cover plate assembly provided by the utility model is used for sealing the battery shell, and is relatively good in sealing performance and relatively high in structural stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy, in particular to a cover plate assembly and a battery. BACKGROUND

[0002] Lithium batteries are widely used in electric vehicles, energy storage systems, consumer electronics and other fields. A lithium battery includes a battery shell, a battery cell arranged in the shell, and a cover plate assembly for sealing the battery shell. The cover plate assembly provides electrical connection and mechanical protection for the battery and ensures the sealing performance, safety protection, insulation performance and environmental adaptability of the battery.

[0003] However, a large amount of gas is often generated in the battery due to electrochemical reaction and temperature rise of the working environment, which causes the internal pressure of the battery shell to rise sharply, resulting in sealing failure of the cover plate assembly to the battery shell. Utility model content

[0004] The present application provides a cover plate assembly and a battery. The cover plate assembly is used for sealing the battery shell and has good sealing performance and high structural stability.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] The first aspect of the present application provides a cover plate assembly for sealing a battery shell, which comprises:

[0007] a base plate having a mounting hole; an electrode terminal, a fixing sleeve and a first sealing member, the fixing sleeve being sleeved on the electrode terminal and fixedly connected with the base plate, the electrode terminal comprising a main body portion and an extension portion connected with each other, at least part of the fixing sleeve being covered on the extension portion, the main body portion being sealingly connected to the mounting hole through the first sealing member; a connecting piece and a support, the connecting piece being fixedly connected to the main body portion, and the support being connected between the base plate and the connecting piece.

[0008] In a possible implementation, the support is a heat insulation member, and the heat insulation temperature of the heat insulation member is greater than or equal to 120℃.

[0009] In a possible implementation, the main body portion of the electrode terminal is welded to the connecting piece.

[0010] In a possible implementation, the main body portion of the electrode terminal has a first surface and a second surface, the first surface and the second surface being opposite along the thickness direction of the main body portion, and the first surface being welded to the connecting piece.

[0011] In a possible implementation, the second surface is provided with a welding positioning groove.

[0012] In a possible implementation, the connecting piece has a third surface, the third surface is welded with the first surface of the main body part, the first surface of the main body part and the third surface of the connecting piece are correspondingly provided with a first positioning hole and a second positioning hole, and the first positioning hole and the second positioning hole are coaxially arranged.

[0013] In a possible implementation, the extension part is annular, the annular extension part extends outward along the circumference of the main body part, and the annular extension part is parallel to the substrate.

[0014] In a possible implementation, the fixing sleeve is formed by injection molding on the outer periphery of the electrode terminal; and / or, the fixing sleeve is an insulating sleeve.

[0015] In a possible implementation, the connecting piece has a flange, and the connecting piece is clamped in the clamping groove through the flange.

[0016] The cover assembly provided in the first aspect of the application has at least the following beneficial effects:

[0017] The cover assembly seals the mounting hole of the electrode terminal and the substrate through the sealing piece, and connects the connecting piece and the substrate through the supporting piece. After the cover assembly is capped on the battery shell, the sealing performance of the battery shell and the mounting stability of the connecting piece are strengthened, the liquid and gas in the shell are not easy to leak from the mounting hole of the substrate, and the extension part matched with the fixing sleeve on the electrode terminal improves the contact area of the fixing sleeve and the electrode terminal and strengthens the stability of the electrode terminal fixed on the substrate by the fixing sleeve.

[0018] The second aspect of the application provides a battery, which comprises:

[0019] A battery shell has a containing cavity, and the containing cavity has an opening.

[0020] An electrode core is arranged in the containing cavity.

[0021] The cover assembly as in any of the solutions of the first aspect is capped on the opening to seal the containing cavity.

[0022] The battery provided in the second aspect of the application has all the beneficial effects of the cover assembly provided in the first aspect of the application, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced. Obviously, the accompanying drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those of ordinary skill in the art without any creative effort on the basis of these drawings.

[0024] Figure 1 The overall structural schematic diagram of the cover plate assembly provided in the embodiments of the present application is shown in the figure.

[0025] Figure 2 The top view of the cover plate assembly provided in the embodiments of the present application is shown in the figure.

[0026] Figure 3 The front view of the cover plate assembly provided in the embodiments of the present application is shown in the figure.

[0027] Figure 4 The sectional view of the cover plate assembly in Figure 3

[0028] The enlarged structural schematic diagram of the A area in Figure 5 Figure 4

[0029] Explanation of reference signs:

[0030] 100, substrate;

[0031] 110, mounting hole;

[0032] 200, electrode terminal;

[0033] 210, main body part;

[0034] 211, first surface; 2111, first positioning hole;

[0035] 212, second surface; 2121, welding positioning groove;

[0036] 220, extension part;

[0037] 300, fixing sleeve;

[0038] 400, first sealing member;

[0039] 500, connecting sheet;

[0040] 510, third surface; 511, second positioning hole;

[0041] 600, supporting member;

[0042] 700, insulating member;

[0043] 710, clamping groove; 720, flange; ​​

[0044] 800, liquid injection hole;

[0045] 900, explosion-proof member.

[0046] The specific embodiments of the present application have been shown and described in the above drawings, and will be described in more detail hereinafter. The drawings and the written description are not intended to restrict the scope of the present application in any way, but to explain the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0047] As described in the background, lithium batteries have a wide range of applications in electric vehicles, energy storage systems, consumer electronics and other fields, and lithium batteries include a battery shell, an electric core arranged in the shell, and a cover plate assembly for sealing the battery shell. The cover plate assembly provides electrical connection and mechanical protection for the battery, and ensures the sealing performance, safety protection, insulation performance and environmental adaptability of the battery.

[0048] However, the battery is often prone to produce a large amount of gas due to electrochemical reaction and temperature rise of the working environment, which causes the internal pressure of the battery shell to rise sharply, resulting in the sealing failure of the cover plate assembly to the battery shell.

[0049] To solve the above technical problems, the present application provides a cover plate assembly, which connects the connecting sheet and the substrate through the support piece. After the cover plate assembly is sealed to the battery shell, the sealing performance of the battery shell and the installation stability of the connecting sheet are strengthened. The liquid and gas inside the shell are not easy to leak from the substrate mounting hole. In addition, the epitaxial part matched with the fixing sleeve is arranged and fixed on the electrode terminal, which increases the contact area of the fixing sleeve and the electrode terminal, and strengthens the stability of the electrode terminal fixed on the substrate by the fixing sleeve.

[0050] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0051] Reference Figures 1 to 5The cover plate assembly provided by the embodiment of the application is used for sealing a battery shell, and comprises a base plate 100 having a mounting hole 110, an electrode terminal 200, a fixing sleeve 300 and a first sealing member 400, the fixing sleeve 300 is sleeved on the electrode terminal 200 and fixedly connected with the base plate 100, the electrode terminal 200 comprises a main body part 210 and an extension part 220 connected with each other, at least part of the fixing sleeve 300 is wrapped on the extension part 200, and the main body part 210 is sealingly connected to the mounting hole 110 through the first sealing member 400; a connecting sheet 500 and a supporting member 600, the connecting sheet 500 is fixedly connected to the main body part 210 and sealingly connected to the mounting hole 110 through the supporting member 600, and the connecting sheet 500 is used for electrically connecting with a tab.

[0052] In this way, the mounting holes 110 of the electrode terminal 200 and the base plate 100 are respectively sealed by the sealing members, and the connecting sheet 500 and the base plate 100 are connected through the supporting member 600, after the cover plate assembly is sealed on the battery shell, the sealing performance of the battery shell and the installation stability of the connecting sheet 500 are strengthened, that is, the electrode terminal 200, the base plate 100 and the first sealing member 400 form an upper sealing area, the connecting sheet 500, the base plate 100 and the supporting member 600 form a lower sealing area, when the sealing area formed by the fixed connection of the electrode terminal 200 and the connecting sheet 500 is sealed badly, the cover plate assembly can still maintain good sealing for the battery shell through the upper sealing area, so that the liquid and gas in the shell are not easy to leak from the mounting hole 110 of the base plate 100, and the extension part 220 provided on the electrode terminal 200 and matched with the fixing sleeve 300 improves the contact area of the fixing sleeve 300 and the electrode terminal 200, and strengthens the stability of the fixing sleeve 300 in fixing the electrode terminal 200 on the base plate 100.

[0053] Further, two mounting holes 110 are arranged on the base plate 100 at intervals and used for mounting positive and negative electrode terminals, the negative electrode terminal is taken as an example in the embodiment and described in combination with the drawings, and the sealing structure on the positive electrode terminal is the same as that on the negative electrode.

[0054] For example, the fixing sleeve 300 is a plastic part, which is arranged on the outer periphery of the extension part 220 of the electrode terminal 200 through an injection molding process, the contact area of the extension part 220 and the fixing sleeve 300 is increased, the adhesion of the fixing sleeve 300 on the extension part 220 is strengthened, and then the mechanical strength of the electrode terminal 200 on the base plate 100 is improved, and the possibility of terminal falling off is reduced.

[0055] Further, the first sealing member 400 and the support member 600 are both elastic sealing rings, which are sleeved on the main body part 210 of the electrode terminal 200 and the connecting sheet 500 respectively. By arranging the extension part 220, the cover plate assembly can be arranged on the battery shell, and the internal gas production of the shell is prevented. The gas pressure makes the electrode terminal 200 bear force along the thickness direction of the electrode terminal 200. The sealing ring is compressed under the pressure of the gas produced in the battery. The sealing ring rebounds to give the electrode terminal 200 an impact force, so that the electrode terminal 200 and the fixed sleeve are separated, and the sealing failure is caused.

[0056] In other examples, the support member 600 can not be a sealing structure, and the support member 600 is provided with a through hole and is connected between the connecting sheet 500 and the substrate 100 as a support structure. In other examples, the support member 600 is made of an insulating material, and the insulating performance between the substrate 100 and the connecting sheet 500 is improved.

[0057] In some embodiments, the main body part 210 of the electrode terminal 200 is welded to the connecting sheet 500. For example, the main body part 210 of the electrode terminal 200 is welded to the connecting sheet 500 by laser welding. Further, the main body part 210 of the electrode terminal 200 is welded to the connecting sheet 500 by laser penetration welding, so as to form a flow component to conduct the current between the battery cell and external elements after the cover plate assembly is arranged on the battery shell containing the battery cell.

[0058] In some embodiments, the main body part 210 of the electrode terminal 200 has a first surface 211 and a second surface 212. The first surface 211 and the second surface 212 are opposite to each other along the thickness direction of the main body part 210. The first surface 211 is welded to the connecting sheet 500. Further, the second surface 212 is provided with a welding positioning groove 2121. Specifically, the welding positioning groove 2121 is a sink groove. In this way, the positioning groove provides a clear physical reference point, so that the welding equipment (such as a laser welding machine or an ultrasonic welding machine) can accurately align the welding position. By using these grooves, the deviation of the welding position can be avoided, the welding precision is improved, and the misalignment of the connecting sheet 500 and the main body part 210 during the welding process can be prevented, so as to ensure the alignment of the welding points and the welding quality.

[0059] In some embodiments, the connecting sheet 500 has a third surface 510, and the third surface 510 is welded to the first surface 211 of the main body part 210. The first surface 211 of the main body part 210 and the third surface 510 of the connecting sheet 500 are correspondingly provided with a first positioning hole 2111 and a second positioning hole 511. The first positioning hole 2111 and the second positioning hole 511 are coaxially arranged. In this way, the welding alignment precision of the connecting sheet 500 and the electrode terminal 200 is improved, and the connection strength of the two is ensured.

[0060] In some embodiments, the epitaxial portion 220 is annular, the annular epitaxial portion 220 extends outward along the circumference of the main body portion 210, and the annular epitaxial portion 220 is parallel to the substrate 100. In this way, a large connection area is ensured between the epitaxial portion 220 and the fixing sleeve 300, and the mounting stability of the fixing sleeve 300 and the electrode terminal 200 on the substrate is improved.

[0061] In some embodiments, the fixing sleeve 300 has a groove, and the epitaxial portion 220 is clamped in the groove. In this way, the structural shape of the fixing sleeve and the electrode terminal 200 is adapted, and the connection stability of the two is improved.

[0062] Further, the fixing sleeve 300 is injection molded on the outer periphery of the electrode terminal 200, which can realize the close combination of the fixing sleeve 300 and the electrode terminal 200, reduce the risk of loosening or displacement, and improve the stability and durability of the structure.

[0063] In more examples, the fixing sleeve 300 is an insulating sleeve to provide electrical insulation for the cover plate assembly, prevent the electrode terminal 200 from contacting other metal components, and avoid short circuit phenomenon.

[0064] In some embodiments, the cover plate assembly further includes an insulating piece 700, the insulating piece 700 is provided with a clamping groove 710, the connecting piece 500 has a flange 720, the connecting piece 500 is clamped in the clamping groove 710 through the flange 720, and the insulating piece 700 is fixedly connected to the substrate 100. For example, the insulating piece 700 is provided with a first connecting hole, the substrate 100 is provided with a second connecting hole corresponding to the first connecting hole, and the insulating piece 700 is fixed to the substrate 100 through a threaded connecting piece; or the insulating piece 700 is welded to the side of the substrate 100 away from the fixing sleeve. In this way, it is ensured that the connecting piece 500 will not loosen or displace during use, and the insulating piece 700 can improve the mechanical strength of the entire cover plate assembly and prevent the connecting piece 500 from falling off or deforming under external conditions such as vibration or impact.

[0065] On the basis of the above-mentioned embodiments, the support can be improved to be a heat insulation piece with a heat insulation temperature greater than or equal to 120℃. For example, the heat insulation temperature of the support is 150℃, or the heat insulation temperature of the support is 200℃. Further, the support is made of ceramic material or mica, which has both heat insulation and insulation properties.

[0066] In some embodiments, the substrate 100 is provided with a liquid injection hole 800 for introducing electrolyte, so as to ensure accurate addition of electrolyte, exclude air, balance pressure, and effectively seal after liquid injection.

[0067] In some embodiments, the cover plate assembly further comprises an explosion-proof device, the base plate 100 is provided with an explosion-proof hole, and the explosion-proof device is installed in the explosion-proof hole. For example, the explosion-proof device is an explosion-proof valve. When excessive gas is generated inside the battery due to an electrochemical reaction, temperature rise or other reasons, the internal pressure gradually increases. The explosion-proof valve automatically opens when the pressure reaches a preset threshold, releasing the excess gas inside, preventing the pressure from continuing to rise, thereby avoiding battery explosion. By timely releasing the pressure inside the battery housing, the explosion-proof valve can protect the structural integrity of the battery and prevent the battery housing from breaking or deforming.

[0068] Another aspect of the present application also provides a battery, comprising: a battery shell having a receiving cavity, the receiving cavity having an opening; an electric core arranged in the receiving cavity; and the cover plate assembly provided by any one of the embodiments of the first aspect, the cover plate assembly covering the opening to seal the receiving cavity.

[0069] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0070] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.

[0071] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0072] In the present application, unless specifically stated and limited otherwise, a first feature "on" or "under" a second feature can be directly contacting the first and second features, or indirectly contacting the first and second features through an intermediate medium. Also, a first feature "over", "above" and "on top of" a second feature can be directly above or obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. A first feature "under", "below" and "underneath" a second feature can be directly below or obliquely below the second feature, or simply means that the first feature is horizontally lower than the second feature.

[0073] The embodiments or implementations in the present specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between the embodiments can be mutually referred to.

[0074] It should be noted that the embodiments referred to in the specification as "one embodiment", "an embodiment", "example embodiment", "some embodiments" and the like can include a specific feature, structure or characteristic, but not necessarily every embodiment. In addition, such phrases do not necessarily refer to the same embodiment. In addition, when a specific feature, structure or characteristic is described in combination with an embodiment, it is within the knowledge of those skilled in the art to realize such feature, structure or characteristic in combination with other embodiments, whether explicitly described or not.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and such modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A cover plate assembly, characterized by A cover plate assembly for sealing a battery housing, the cover plate assembly comprising: a base plate having a mounting hole; an electrode terminal, a fixing sleeve and a first sealing member, the fixing sleeve being sleeved on the electrode terminal and fixedly connected with the base plate, the electrode terminal comprising a main body portion and an extension portion connected with each other, at least part of the fixing sleeve being covered on the extension portion, the main body portion being sealingly connected to the mounting hole through the first sealing member; a connecting piece and a support, the connecting piece being fixedly connected to the main body portion, the support being connected between the base plate and the connecting piece.

2. The cover plate assembly of claim 1, wherein, The support is a heat insulation member, and a heat insulation temperature of the heat insulation member is greater than or equal to 120℃.

3. The cover plate assembly of claim 1, wherein, The main body portion of the electrode terminal is welded to the connecting piece.

4. The cover plate assembly of claim 3, wherein, The main body portion of the electrode terminal has a first surface and a second surface, the first surface and the second surface being opposite to each other along a thickness direction of the main body portion, and the first surface is welded to the connecting piece.

5. The cover plate assembly of claim 4, wherein, The second surface is provided with a welding positioning groove.

6. The cover plate assembly of claim 4, wherein, The connecting piece has a third surface, the third surface being welded to the first surface of the main body portion, the first surface of the main body portion and the third surface of the connecting piece being provided with a first positioning hole and a second positioning hole in correspondence, and the first positioning hole and the second positioning hole are coaxially arranged.

7. The cover plate assembly of any one of claims 1-6, wherein, The extension portion is annular, the annular extension portion extending outward along a circumferential direction of the main body portion, and the annular extension portion is parallel to the base plate.

8. The cover plate assembly of any one of claims 1-6, wherein, The fixing sleeve is injection molded on an outer periphery of the electrode terminal; and / or, the fixing sleeve is an insulating sleeve.

9. The cover plate assembly of any one of claims 1-6, wherein, Further comprising an insulating member provided with a clamping groove, the connecting piece having a flange, and the connecting piece is clamped to the clamping groove through the flange.

10. A battery, characterized by A battery housing comprising: a housing having a receiving cavity, the receiving cavity having an opening; a battery cell arranged in the receiving cavity; a cover plate assembly as claimed in any one of claims 1-9, the cover plate assembly being arranged on the opening for sealing the receiving cavity.

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