Top patch, top cover assembly, battery and electric device

Abstract

The application provides a top patch, a top cover assembly, a battery and an electric device. The top patch comprises a bottom layer, a detection layer and a top layer which are sequentially stacked; the bottom layer is provided with a plurality of liquid guide holes, the plurality of liquid guide holes are arranged at intervals on the bottom layer, each liquid guide hole penetrates the bottom layer along the thickness direction of the bottom layer, and the bottom layer is used for connecting with the top cover; the detection layer comprises a first surface and a second surface, the first surface and the second surface are oppositely arranged in the thickness direction of the detection layer, the first surface is connected with the bottom layer and covers the plurality of liquid guide holes, the second surface is connected with the top layer, the detection layer is used for changing color when contacting with electrolyte, and the top layer is used for observing the color change of the detection layer. The technical scheme of the application can improve the liquid leakage detection capability in the top cover assembly and avoid continuous liquid leakage of the battery.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and in particular to a top patch, a top cover assembly, a battery, and an electrical device. Background Technology

[0002] With the development of green energy and the increasing environmental awareness of the public, the application of recyclable batteries is becoming more and more widespread. Currently, battery manufacturing relies heavily on welding to join multiple components. However, waste gases generated during welding can easily enter the weld seam, affecting its strength and causing air and liquid leaks. Furthermore, current technology cannot promptly detect air and liquid leaks in the top cover assembly. Summary of the Invention

[0003] Embodiments of this application provide a top patch, a top cover assembly, a battery, and an electrical device, which can improve the leakage detection capability of the top cover assembly and prevent continuous leakage of the battery.

[0004] In a first aspect, this application provides a top patch, the top patch comprising a bottom layer, a detection layer and a top layer stacked sequentially;

[0005] The bottom layer is provided with a plurality of liquid guiding holes, which are spaced apart on the bottom layer. Each liquid guiding hole penetrates the bottom layer along the thickness direction of the bottom layer. The bottom layer is used to connect with the top cover.

[0006] The detection layer includes a first surface and a second surface, which are disposed opposite to each other in the thickness direction of the detection layer. The first surface is connected to the bottom layer and covers a plurality of liquid guiding holes. The second surface is connected to the top layer. The detection layer is used to change color when in contact with electrolyte, and the top layer is used to observe the color change of the detection layer.

[0007] Understandably, battery manufacturing relies heavily on welding to connect multiple components. However, welding processes easily generate waste gases (such as carbon dioxide and hydrogen). These gases entering the weld seam can affect its strength, causing weaker welds to widen and leading to air / liquid leakage. However, current technology cannot promptly detect air and liquid leaks in the top cover assembly.

[0008] Therefore, in this embodiment, by enabling the detection layer to change color upon contact with the electrolyte, when leakage occurs in the top cover assembly, the leaked electrolyte can penetrate through the bottom layer to the detection layer, causing the detection layer to change color and be identified by humans or machine vision, thus preventing continuous leakage. Furthermore, by observing the location of the color change on the detection layer from the top layer, the location of the leakage in the top cover assembly can also be pinpointed.

[0009] In one possible implementation, the top patch further includes an adhesive layer connected between the bottom layer and the top cover. The adhesive layer falls into the projection of the bottom layer along the thickness direction of the top patch and is offset from the plurality of liquid guiding holes.

[0010] In one possible implementation, the top patch further includes an adhesive layer connected between the bottom layer and the top cover, the adhesive layer covering a plurality of the liquid guiding holes, and the adhesive layer being made of a neutral or alkaline material.

[0011] In one possible implementation, the top layer is made of a transparent or translucent material.

[0012] In one possible implementation, the bottom layer is provided with a first positioning structure, the detection layer is provided with a second positioning structure, and the top layer is provided with a third positioning structure. The first positioning structure and the second positioning structure are disposed opposite to each other in the thickness direction of the top patch, and the third positioning structure and the second positioning structure are disposed opposite to each other in the thickness direction of the top patch.

[0013] At least a portion of the first positioning structure is located within the second positioning structure, and at least a portion of the second positioning structure is located within the third positioning structure; or...

[0014] At least a portion of the second positioning structure is located within the first positioning structure, and at least a portion of the third positioning structure is located within the second positioning structure.

[0015] In one possible implementation, the bottom layer has a first protruding structure that protrudes from the surface of the bottom layer toward the detection layer, and the projection of the detection layer onto the bottom layer along the thickness direction of the top patch is offset from the first protruding structure; and / or,

[0016] The top layer is provided with a second protruding structure, which protrudes from the surface of the top layer toward the detection layer. The projection of the detection layer on the top layer along the thickness direction of the top patch is offset from the second protruding structure.

[0017] In one possible implementation, the outer edge of the bottom layer is also connected to the outer edge of the top layer to enclose the detection layer in the top layer and the bottom layer.

[0018] In one possible implementation, the maximum dimension L1 of the bottom layer in the length direction of the top patch, the maximum dimension L2 of the detection layer in the length direction of the top patch, and the maximum dimension L3 of the top layer in the length direction of the top patch satisfy the following relationship:

[0019] L1 = L3;

[0020] 10mm ≥ L1 - L2 ≥ 2mm;

[0021] 10mm≥L3-L2≥2mm.

[0022] In one possible implementation, the maximum dimension W1 of the bottom layer in the width direction of the top patch, the maximum dimension W2 of the detection layer in the width direction of the top patch, and the maximum dimension W3 of the top layer in the width direction of the top patch satisfy the following relationship:

[0023] W1 = W3;

[0024] 10mm≥W1-W2≥2mm;

[0025] 10mm≥W3-W2≥2mm.

[0026] In one possible implementation, the bottom layer has a first hole that penetrates the bottom layer along its thickness direction; the detection layer has a second hole that penetrates the detection layer along its thickness direction; and the top layer has a third hole that penetrates the top layer along its thickness direction. The first hole, the second hole, and the third hole are sequentially connected and coaxially arranged, and the first hole, the second hole, and the third hole are used to expose the explosion-proof valve.

[0027] The maximum dimensions D1 of the first hole, D2 of the second hole, and D3 of the third hole in the length direction of the top patch satisfy the following relationship:

[0028] D1 = D3;

[0029] 10mm≥D2-D1≥2mm;

[0030] 10mm≥D2-D3≥2mm.

[0031] In one possible implementation, the maximum dimensions H1 of the first hole in the width direction of the top patch, the maximum dimensions H2 of the second hole in the width direction of the top patch, and the maximum dimensions H3 of the third hole in the width direction of the top patch satisfy the following relationship:

[0032] H1 = H3;

[0033] 10mm≥H2-H1≥2mm;

[0034] 10mm≥H2-H3≥2mm.

[0035] In one possible implementation, the bottom layer has a fourth hole that penetrates the bottom layer along its thickness direction, and the fourth hole and the first hole are spaced apart along the length direction of the bottom layer. The detection layer has a fifth hole that penetrates the detection layer along its thickness direction, and the fifth hole and the second hole are spaced apart along the length direction of the detection layer. The top layer has a sixth hole that penetrates the top layer along its thickness direction, and the sixth hole and the third hole are spaced apart along the length direction of the top layer. The fourth hole, the fifth hole, and the sixth hole are sequentially connected and coaxially arranged, and the fourth hole, the fifth hole, and the sixth hole are used for the passage of the electrode post.

[0036] The maximum dimensions Φ1 of the fourth hole, Φ2 of the fifth hole, and Φ3 of the sixth hole in the length direction of the top patch satisfy the following relationship:

[0037] Φ1 = Φ3;

[0038] 8mm≥Φ2-Φ1≥2mm;

[0039] 8mm≥Φ2-Φ3≥2mm.

[0040] In one possible implementation, the top patch further includes an identifier disposed on the surface of the top layer opposite to the detection layer, or the identifier disposed on the detection layer and located between the detection layer and the top layer.

[0041] In one possible implementation, the bottom layer has a seventh hole that penetrates the bottom layer along its thickness direction, and the detection layer has an eighth hole that penetrates the detection layer along its thickness direction. The seventh hole and the eighth hole are coaxially arranged and connected, and the seventh hole and the eighth hole are used to expose the markings on the top cover.

[0042] In one possible implementation, the maximum dimension d1 of the seventh hole in the length direction of the top patch and the maximum dimension d2 of the eighth hole in the length direction of the top patch satisfy the following relationship:

[0043] 6mm≥d2-d1≥1mm.

[0044] In one possible implementation, the maximum dimension h1 of the seventh hole in the width direction of the top patch and the maximum dimension h2 of the eighth hole in the width direction of the top patch satisfy the following relationship:

[0045] 6mm≥h2-h1≥1mm.

[0046] Secondly, this application also provides a top cover assembly, the top cover assembly including a top cover and a top patch as described above, the top cover being connected to the bottom layer.

[0047] Thirdly, this application also provides a battery, the battery including the top cover assembly as described above.

[0048] Fourthly, this application also provides an electrical device, which includes the battery described above. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the energy storage system provided in an embodiment of this application;

[0050] Figure 2 This is a schematic diagram of a battery structure provided in an embodiment of this application;

[0051] Figure 3 This is a schematic diagram of a partial structure of the top cover assembly provided in an embodiment of this application;

[0052] Figure 4 This is a schematic diagram of a top patch structure provided in an embodiment of this application;

[0053] Figure 5a It is along Figure 4 A schematic cross-sectional view of the top patch obtained by cutting along section line AA;

[0054] Figure 5b yes Figure 5a A magnified view of region B in the middle;

[0055] Figure 6 yes Figure 4 The diagram shows the underlying structure of the top patch;

[0056] Figure 7 yes Figure 4 A schematic diagram of the detection layer of the top patch shown;

[0057] Figure 8 yes Figure 4 The diagram shows the structure of the top layer of the top patch;

[0058] Figure 9 This is another structural schematic diagram of the top patch provided in the embodiments of this application;

[0059] Figure 10 yes Figure 9 The diagram shows the underlying structure of the top patch;

[0060] Figure 11 yes Figure 9 The diagram shows the structure of the detection layer of the top patch.

[0061] Figure label:

[0062] Energy storage system 500, power conversion device 510, first user load 520, second user load 530, electrical equipment 400, battery 300, casing 310, battery cell 320, top cover assembly 200, top cover 210, top patch 100, bottom layer 10, detection layer 20, top layer 30, adhesive layer 40, liquid guiding hole 11, first positioning structure 12, first protrusion structure 13, first hole 14, fourth hole 15, first surface 21, second surface 22, second positioning structure 23, second hole 24, fifth hole 25, third positioning structure 26, second surface 27, second surface 28, second positioning structure 29, second hole 20, fifth hole 21, third surface 22, second positioning structure 23, second hole 24, fifth hole 25, third positioning structure 20, second surface ... Position structure 31, second protrusion structure 32, third hole 33, sixth hole 34, mark 50, first through hole 60, seventh hole 61, eighth hole 62, maximum dimension L1 of bottom layer 10 in the length direction of top patch 100, maximum dimension W1 of bottom layer 10 in the width direction of top patch 100, maximum dimension L2 of detection layer 20 in the length direction of top patch 100, maximum dimension W2 of detection layer 20 in the width direction of top patch 100, maximum dimension L3 of top layer 30 in the length direction of top patch 100, top layer 30 The maximum dimensions W3 in the width direction of the top patch 100, the maximum dimensions D1 and H1 in the length direction of the first hole 14 in the width direction of the top patch 100, the maximum dimensions Φ1 in the length direction of the fourth hole 15 in the length direction of the top patch 100, the maximum dimensions D2 and H2 in the length direction of the second hole 24 in the width direction of the top patch 100, the maximum dimensions Φ2 in the length direction of the fifth hole 25 in the length direction of the top patch 100, and the third hole 33 are specified in the table. The maximum dimension D3 in the length direction of the top patch 100, the maximum dimension H3 in the width direction of the third hole 33, the maximum dimension Φ3 in the length direction of the sixth hole 34, the maximum dimension d1 in the length direction of the seventh hole 61, the maximum dimension h1 in the width direction of the seventh hole 61, the maximum dimension d2 in the length direction of the eighth hole 62, the maximum dimension h2 in the width direction of the eighth hole 62, and the hot melt zone S. Detailed Implementation

[0063] For ease of understanding, the terminology used in the embodiments of this application will be explained first.

[0064] And / or: This is simply a way of describing the relationship between related objects. It indicates that there can be three kinds of relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0065] Multiple: refers to two or more.

[0066] Connection: should be interpreted broadly. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through an intermediary.

[0067] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be noted that the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0068] Embodiments of this application provide a top patch, a top cover assembly, a battery, and an electrical device.

[0069] Because the energy we need is highly time- and space-dependent, in order to utilize energy rationally and improve energy efficiency, it is necessary to store one form of energy in the same way or by converting it into another, and then release it in a specific energy form according to future application needs. As we all know, the generation of green electricity currently relies heavily on photovoltaic, wind, and hydropower. However, wind and solar energy are generally characterized by strong intermittency and large fluctuations, which can cause grid instability, insufficient power during peak demand periods, and excessive power during off-peak periods. Unstable voltage can also damage the power grid. Therefore, insufficient electricity demand or insufficient grid capacity can lead to the problem of "wind and solar curtailment." Solving these problems requires energy storage. This involves converting electrical energy into other forms of energy through physical or chemical means and storing it, then releasing the stored energy as electricity when needed. Simply put, energy storage is like a large "power bank," storing electrical energy when photovoltaic and wind power are abundant and releasing the stored electricity when needed.

[0070] Taking electrochemical energy storage as an example, an embodiment of this application provides an electrical device 400, which is equipped with a set of chemical batteries. The main purpose is to use the chemical elements in the chemical batteries as energy storage medium. The charging and discharging process is accompanied by the chemical reaction or change of the energy storage medium. Simply put, the electrical energy generated by wind and solar energy is stored in the chemical batteries. When the use of external electrical energy reaches its peak, the stored electricity is released for use, or transferred to places where electricity is scarce for use.

[0071] Current energy storage applications are quite widespread, including generation-side energy storage, grid-side energy storage, renewable energy grid-connected energy storage, and user-side energy storage. The corresponding types of electrical equipment include:

[0072] Large energy storage containers used in grid-side energy storage scenarios can serve as high-quality active and reactive power regulation power sources in the power grid, enabling load matching of electrical energy in time and space, enhancing the absorption capacity of renewable energy, and playing a significant role in grid system backup, alleviating peak load power supply pressure, and peak shaving and frequency regulation.

[0073] Small and medium-sized energy storage cabinets used in commercial and industrial energy storage scenarios on the user side, and small household energy storage boxes used in residential energy storage scenarios on the user side, mainly operate under the "peak shaving and valley filling" mode. Because there are significant price differences in electricity during peak and off-peak periods based on electricity demand, users typically charge the energy storage cabinets / boxes during off-peak hours to reduce costs; then, during peak hours, they release the electricity from the energy storage cabinets / boxes for use, thus saving on electricity bills. Furthermore, in remote areas and regions prone to natural disasters such as earthquakes and hurricanes, the presence of household energy storage cabinets / boxes effectively provides users with backup power for themselves and the power grid, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0074] Please see Figure 1 , Figure 1 This is a schematic diagram of the energy storage system 500 provided in an embodiment of this application. This embodiment uses a home energy storage scenario in user-side energy storage as an example for illustration; however, the electrical equipment 400 in this application is not limited to a home energy storage scenario.

[0075] Embodiments of this application provide an energy storage system 500, which includes a power conversion device 510, a first user load 520, a second user load 530, and an electrical device 400. The electrical device 400 is a small energy storage box that can be wall-mounted to an outdoor wall. Specifically, photovoltaic panels can convert solar energy into electrical energy during periods of low electricity prices, and the electrical device 400 stores this electrical energy and supplies it to streetlights and household appliances during peak electricity prices, or provides power during power outages / power interruptions.

[0076] The electrical device 400 may include, but is not limited to, individual batteries, battery modules, battery packs, and battery systems. When the electrical device 400 includes multiple batteries, the multiple batteries are electrically connected and all are located inside the casing of the electrical device 400, which protects them from interference from the external environment. Exemplarily, the multiple batteries are arranged at intervals. The multiple batteries can be connected in series, in parallel, or in a combination of series and parallel connections to achieve greater capacity and power. The embodiments of this application are illustrated using the example of an electrical device 400 including batteries, but it should be understood that the electrical device 400 is not limited thereto.

[0077] Please see Figure 2 , Figure 2This is a schematic diagram of a battery 300 provided in an embodiment of this application.

[0078] For ease of description, the length direction of battery 300 is defined as the X direction, the width direction as the Y direction, and the height direction as the Z direction. The X, Y, and Z directions are all perpendicular to each other.

[0079] The battery 300 may include a top cover assembly 200, a housing 310, and a battery cell 320. The top cover assembly 200 is connected to the housing 310 and forms a receiving space with the housing 310, within which the battery cell 320 is located. Exemplarily, the top cover assembly 200 may be welded to the housing 310. The housing 310 may be made of a metallic material, such as aluminum alloy. The battery 300 may be a cylindrical battery 300 or a prismatic battery 300, etc.

[0080] It should be noted that, Figure 2 The purpose is merely to illustratively describe the connection relationship between the top cover assembly 200, the housing 310, and the battery cell 320, and is not to specifically limit the connection positions, specific structures, or quantities of each device. Furthermore, the structures illustrated in the embodiments of this application do not constitute a specific limitation on the battery 300. In other embodiments of this application, the battery 300 may include... Figure 2 This may involve more or fewer components, or combining certain components, or splitting certain components, or different component arrangements. Figure 2 The components shown can be implemented in hardware, software, or a combination of both.

[0081] Please refer to the following: Figure 2 and Figure 3 , Figure 3 This is a schematic diagram of a portion of the structure of the top cover assembly 200 provided in an embodiment of this application.

[0082] The top cover assembly 200 may include a top patch 100, a top cover 210, an explosion-proof valve (not shown), and terminals (not shown). The top cover 210 may be connected to the housing 310 to form a housing space for the battery 300. The top cover 210 may have an explosion-proof hole. The explosion-proof hole extends through the top cover 210 along its thickness direction. The explosion-proof valve is connected to the explosion-proof hole on the top cover 210 and is used to provide pressure relief protection for the battery 300. The top patch 100 is connected to the side of the top cover 210 opposite to the housing 310. The terminals pass through the top patch 100 and the top cover 210 and can serve as electrodes for the battery 300.

[0083] The number of terminals can be two. The two terminals are spaced apart along the length of the top cover 210. The two terminals are the positive terminal and the negative terminal.

[0084] It should be noted that, Figure 3 The purpose is merely to illustratively describe the connection relationship between the top patch 100 and the top cover 210, and is not to specifically limit the connection positions, specific structures, or quantities of each device. The structures illustrated in the embodiments of this application do not constitute a specific limitation on the top cover assembly 200. In other embodiments of this application, the top cover assembly 200 may include more than Figure 3 This may involve more or fewer components, or combining certain components, or splitting certain components, or different component arrangements. Figure 3 The components shown can be implemented in hardware, software, or a combination of both.

[0085] Understandably, rechargeable batteries are a type of battery with great development potential, widely used in electronic products, electric vehicles, and power grids due to their advantages such as long cycle life, high specific energy, low self-discharge, and no memory effect. During manufacturing, batteries often rely on welding to connect multiple components, such as the connection between the top cover and the terminals, the top cover and the casing, and the top cover and the sealing pins. However, the welding process generates waste gases (such as carbon dioxide and hydrogen), which can enter the weld and affect its strength. During subsequent module assembly and long-term battery charging and discharging, weaker welds are prone to developing larger gaps, leading to air / liquid leakage. Furthermore, the sealing performance at the terminals currently relies mainly on the compression of the sealing ring. If there are problems with the incoming materials of the sealing ring or if the compression of the sealing ring is reduced due to welding / high temperatures, air / liquid leakage from the cell is also possible. Additionally, many tests in the GB-T36276-2023 standard for lithium-ion batteries for power storage require that the cell "do not rupture at any location other than the explosion-proof valve or pressure relief point" after the test is completed. Therefore, it is very important to be able to detect whether there is leakage in the top cover assembly of the battery in a timely manner.

[0086] Therefore, embodiments of this application provide a top patch 100 that improves the leakage detection capability of the top cover assembly 200 and prevents continuous leakage of the battery 300. The structure of the top patch 100 will be described in detail below through two specific embodiments.

[0087] First embodiment:

[0088] Please refer to the following: Figure 4 , Figure 5a and Figure 5b , Figure 4 This is a schematic diagram of a top patch 100 provided in an embodiment of this application. Figure 5a It is along Figure 4 The diagram shows a cross-sectional view of the top patch 100 obtained by cutting along section line AA. Figure 5b yes Figure 5a A magnified view of region B in the middle.

[0089] The top patch 100 may include a bottom layer 10, a detection layer 20, and a top layer 30 stacked sequentially. The bottom layer 10 is connected to the top cover 210. The detection layer 20 is connected to the surface of the bottom layer 10 facing away from the top cover 210. The top layer 30 is connected to the surface of the detection layer 20 facing away from the bottom layer 10. This embodiment does not limit the shapes of the bottom layer 10, the detection layer 20, and the top layer 30, as long as they can be connected accordingly. For example, the bottom layer 10, the detection layer 20, and the top layer 30 are all rectangular. Alternatively, the bottom layer 10, the detection layer 20, and the top layer 30 are all circular.

[0090] The dimensions of the bottom layer 10, the detection layer 20, and the top layer 30 can be adjusted according to the size design of the battery 300. Once the size of the battery 300 is determined, their dimensions conform to the following relationship:

[0091] The maximum dimension L1 of the bottom layer 10 in the length direction (X direction in the figure), the maximum dimension L2 of the detection layer 20 in the length direction of the top patch 100, and the maximum dimension L3 of the top layer 30 in the length direction of the top patch 100 satisfy the following relationship:

[0092] L1 = L3;

[0093] 10mm ≥ L1 - L2 ≥ 2mm;

[0094] 10mm≥L3-L2≥2mm.

[0095] The maximum dimension W1 of the bottom layer 10 in the width direction (Y direction in the diagram) of the top patch 100, the maximum dimension W2 of the detection layer 20 in the width direction of the top patch 100, and the maximum dimension W3 of the top layer 30 in the width direction of the top patch 100 satisfy the following relationship:

[0096] W1 = W3;

[0097] 10mm≥W1-W2≥2mm;

[0098] 10mm≥W3-W2≥2mm.

[0099] Understandably, by making the maximum dimensions of the detection layer 20 in both the length and width directions of the top patch 100 smaller than those of the bottom patch 10 and the top patch 30, the outer edges of the bottom patch 10 and the top patch 30 can be connected, thus completely enclosing the detection layer 20 within both the bottom patch 10 and the top patch 30. This creates a relatively sealed environment for the detection layer 20, preventing it from being easily affected by the external environment and contributing to the long-term stability of its detection function.

[0100] In this embodiment, please refer to Figure 4 The area where the detection layer 20 is added to the bottom layer 10 and the top layer 30 is connected by heat fusion (e.g., Figure 4 The shaded area in the diagram shows the connection between the hot melt zone S and the other side.

[0101] Please refer to the following: Figure 5a , Figure 5b and Figure 6 , Figure 6 yes Figure 4 The diagram shows the structure of the bottom layer 10 of the top patch 100.

[0102] The bottom layer 10 may have multiple liquid guiding holes 11. These holes 11 are spaced apart on the bottom layer 10. Each hole 11 penetrates the bottom layer 10 along its thickness direction (Z direction in the diagram). The holes 11 allow electrolyte to pass through. The size of the holes 11 can be selected based on the size of the battery cell 320 and the effectiveness of the leakage detection on the top patch 100. In this embodiment, the size of the holes 11 can be in the range of 0.05mm-1mm (including the endpoint values ​​of 0.05mm and 1mm). For example, the multiple holes 11 can be arranged in an array on the bottom layer 10.

[0103] The bottom layer 10 may be provided with a first positioning structure 12. The first positioning structure 12 protrudes from the surface of the bottom layer 10 facing the detection layer 20 in a direction away from the battery cell 320. The first positioning structure 12 is used to help position and assemble the bottom layer 10 and the detection layer 20, and also serves to prevent mistaken identification. The first positioning structure 12 and the bottom layer 10 can be connected to form an integral structure. For example, the first positioning structure 12 can be connected to the bottom layer 10 by stamping to form an integral structure. Alternatively, the first positioning structure 12 and the bottom layer 10 can also be an integral structure formed by assembly methods such as welding or bonding. It should be noted that the integral structures described below can all be formed by assembly methods such as stamping, welding, or bonding, and will not be described in detail hereafter.

[0104] The number of first positioning structures 12 can be one or more. This embodiment does not limit the shape of the first positioning structure 12 or its position on the bottom layer 10. When there are multiple first positioning structures 12, the shapes of the multiple first positioning structures 12 can be similar, the same, or different.

[0105] It is understandable that when there are multiple first positioning structures 12, the multiple first positioning structures 12 are set as symbols of different shapes, so that the first positioning structure 12 can be used as a marker symbol to help the bottom layer 10 and the detection layer 20 to identify and assemble, and to prevent the bottom layer 10 and the detection layer 20 from being misaligned.

[0106] For one possible application scenario, please refer to [link / reference]. Figure 6 The bottom layer 10 is rectangular in shape. There can be two first positioning structures 12. The two first positioning structures 12 are spaced apart along the length direction (X direction in the diagram) of the bottom layer 10. The two first positioning structures 12 are also spaced apart along the width direction (Y direction in the diagram) of the bottom layer 10. Each first positioning structure 12 is located near a corner of the bottom layer 10. That is, the two first positioning structures 12 are located at opposite corners of the bottom layer 10. One of the first positioning structures 12 is shaped like a "+", and the other is shaped like a "-".

[0107] Understandably, by setting the first positioning structure 12 at the bottom layer 10, the bottom layer 10 and the detection layer 20 can be quickly positioned and assembled, improving production efficiency and preventing installation misalignment. Simultaneously, the two first positioning structures 12 are set as a "+" shape.

[0108] The two shapes, "-" and "-", can further improve the assembly accuracy between the bottom layer 10 and the detection layer 20.

[0109] In this embodiment, the first positioning structure 12 may have a first cavity. The opening of the first cavity is located on the surface of the bottom layer 10 away from the detection layer 20. The first cavity is formed by recessing from the surface of the bottom layer 10 away from the detection layer 20 into the first positioning structure 12.

[0110] In some other embodiments, the first positioning structure 12 may not have a first cavity.

[0111] The bottom layer 10 may further include a first protruding structure 13. The first protruding structure 13 protrudes from the bottom layer 10 relative to the surface of the detection layer 20 in a direction away from the battery cell 320. The first protruding structure 13 is located close to and spaced apart from the first positioning structure 12. The projection of the first protruding structure 13 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 (Z direction in the figure) is offset from the detection layer 20. That is, the projection of the detection layer 20 onto the bottom layer 10 along the thickness direction of the top patch 100 is offset from the first protruding structure 13. In other words, the first protruding structure 13 is located outside the outer edge of the detection layer 20. Specifically, the first protruding structure 13 may be spaced apart from the outer edge of the detection layer 20. The first protruding structure 13 may also abut against the outer edge of the detection layer 20. There are no limitations on this, as long as the first protruding structure 13 can position the detection layer 20 and prevent misalignment between the bottom layer 10 and the detection layer 20. The first protruding structure 13 and the bottom layer 10 can be connected to form an integrated structure.

[0112] The number of first protrusions 13 can be one or more. This embodiment does not limit the shape of the first protrusions 13. When there are multiple first protrusions 13, the shapes of the multiple first protrusions 13 can be the same or different.

[0113] For one possible application scenario, please refer to [link / reference]. Figure 6 The bottom layer 10 is rectangular in shape. There can be two first protrusion structures 13. The two first protrusion structures 13 are spaced apart along the length of the bottom layer 10. The two first protrusion structures 13 are also spaced apart along the width of the bottom layer 10. Each first protrusion structure 13 is located near a corner of the bottom layer 10 and near a first positioning structure 12. That is, the two first protrusion structures 13 are located at opposite corners of the bottom layer 10. One of the first protrusion structures 13 is shaped like a "「". The other first protrusion structure 13 is shaped like a "」". The "「" shaped first protrusion structure 13 is near the "-" shaped first positioning structure 12. The "」" shaped first protrusion structure 13 is near the "+" shaped first positioning structure 12. Furthermore, the projections of the two first protrusion structures 13 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 are located outside the opposite corners of the detection layer 20, thus preventing movement of the detection layer 20.

[0114] Understandably, by setting the first protrusion structure 13 on the bottom layer 10, not only can the movement of the detection layer 20 be prevented, enhancing the connection stability of the detection layer 20, but it can also help the bottom layer 10 and the detection layer 20 to be quickly positioned and assembled, improving production efficiency and preventing installation misalignment. At the same time, the combined use of the first protrusion structure 13 and the first positioning structure 12 can provide double protection for the positioning and assembly between the bottom layer 10 and the detection layer 20, further improving the assembly accuracy between the bottom layer 10 and the detection layer 20.

[0115] Please refer to the following: Figure 4 and Figure 6 The bottom layer 10 may have a first hole 14. The first hole 14 penetrates the bottom layer 10 along its thickness direction. The first hole 14 is coaxially arranged and communicates with the explosion-proof hole of the top cover 210, and is used to expose the explosion-proof valve. The maximum dimension of the first hole 14 in the length direction of the top patch 100 is D1. That is, the maximum dimension of the first hole 14 in the length direction of the bottom layer 10 is D1. The maximum dimension of the first hole 14 in the width direction of the top patch 100 is H1. That is, the maximum dimension of the first hole 14 in the width direction of the bottom layer 10 is H1.

[0116] The bottom layer 10 may also have a fourth hole 15. The fourth hole 15 penetrates the bottom layer 10 along its thickness direction. The fourth hole 15 and the first hole 14 are spaced apart along the length of the bottom layer 10. The fourth hole 15 is used for the passage of the electrode post. The maximum dimension of the fourth hole 15 along the length of the top patch 100 is Φ1. That is, the maximum dimension of the fourth hole 15 along the length of the bottom layer 10 is Φ1.

[0117] Alternatively, the maximum dimension of the fourth hole 15 in the width direction of the top patch 100 is Φ1. That is, the maximum dimension of the fourth hole 15 in the width direction of the bottom layer 10 is Φ1.

[0118] There can be two fourth holes 15. The two fourth holes 15 are spaced apart along the length of the bottom layer 10. One fourth hole 15 is for the positive terminal to pass through. The other fourth hole 15 is for the negative terminal to pass through. The first hole 14 is located between the two fourth holes 15.

[0119] In this embodiment, the material of the bottom layer 10 can be polyethylene terephthalate (PET), polypropylene (PP), etc.

[0120] Please refer to the following: Figure 5a , Figure 5b and Figure 7 , Figure 7 yes Figure 4 The diagram shows the structure of the detection layer 20 of the top patch 100.

[0121] The detection layer 20 may include a first surface 21 and a second surface 22. The first surface 21 and the second surface 22 are disposed opposite each other in the thickness direction (Z direction in the figure) of the detection layer 20. The first surface 21 faces the battery cell 320. The second surface 22 faces away from the battery cell 320. The first surface 21 is connected to the surface of the bottom layer 10 facing the detection layer 20 and covers the liquid guiding holes 11 of the bottom layer 10. The detection layer 20 may be composed of pH test paper or a material layer that can absorb acid and alkalinity indicators, so that the detection layer 20 can change color when in contact with electrolyte to detect electrolyte leakage in the top cover assembly 200.

[0122] The detection layer 20 may be provided with a second positioning structure 23. The second positioning structure 23 protrudes from the second surface 22 in a direction away from the battery cell 320. The protrusion direction of the second positioning structure 23 relative to the detection layer 20 is the same as the protrusion direction of the first positioning structure 12 of the bottom layer 10 relative to the bottom layer 10. The second positioning structure 23 and the first positioning structure 12 of the bottom layer 10 are arranged opposite to each other in the thickness direction of the top patch 100. The second positioning structure 23 is used to help position and assemble the detection layer 20 with the bottom layer 10 and the top layer 30, and also serves to prevent mistaken identity. The second positioning structure 23 and the detection layer 20 can be connected to form an integral structure.

[0123] The number of second positioning structures 23 can be one or more. This embodiment does not limit the shape of the second positioning structures 23. When there are multiple second positioning structures 23, their shapes can be similar, identical, or different. This embodiment also does not limit the position of the second positioning structures 23 on the bottom layer 10, as long as the second positioning structure 23 corresponds to the position of the first positioning structure 12 on the bottom layer 10.

[0124] It is understandable that when there are multiple second positioning structures 23, the multiple second positioning structures 23 are set as symbols of different shapes, so that the second positioning structures 23 can be used as marker symbols to help the detection layer 20 to identify and assemble with the bottom layer 10 and the top layer 30, and to prevent the detection layer 20 from being misaligned with the bottom layer 10 and the top layer 30.

[0125] For one possible application scenario, please refer to [link / reference]. Figure 7 The detection layer 20 is rectangular in shape. There can be two second positioning structures 23. The two second positioning structures 23 are spaced apart along the length direction (X direction in the diagram) of the detection layer 20. The two second positioning structures 23 are also spaced apart along the width direction (Y direction in the diagram) of the detection layer 20. Each second positioning structure 23 is located near a corner of the detection layer 20. That is, the two second positioning structures 23 are located at opposite corners of the detection layer 20. One of the second positioning structures 23 is shaped like a "+", and the other is shaped like a "-".

[0126] Understandably, by setting the second positioning structure 23 in the detection layer 20, the detection layer 20 can be quickly positioned and assembled with the bottom layer 10 and the top layer 30, improving production efficiency and preventing misalignment during installation. Furthermore, setting the two second positioning structures 23 to both "+" and "-" shapes can further improve the assembly accuracy between the detection layer 20 and the bottom layer 10 and the top layer 30.

[0127] In this embodiment, the second positioning structure 23 may have a second cavity. The opening of the second cavity is located on the first surface 21. The second cavity is recessed from the first surface 21 into the second positioning structure 23. The recess direction of the second cavity relative to the second positioning structure 23 is the same as the recess direction of the first cavity of the bottom layer 10 relative to the first positioning structure 12. The second cavity is used to accommodate the first positioning structure 12 of the bottom layer 10 to realize the connection between the detection layer 20 and the bottom layer 10.

[0128] Please refer to the following: Figure 4 and Figure 7 The detection layer 20 may have a second hole 24. The second hole 24 penetrates the detection layer 20 along its thickness direction. The second hole 24 is coaxially arranged and communicates with the explosion-proof hole of the top cover 210 and the first hole 14 of the bottom layer 10, and is used to expose the explosion-proof valve. The maximum dimension of the second hole 24 in the length direction of the top patch 100 is D2. That is, the maximum dimension of the second hole 24 in the length direction of the detection layer 20 is D2. The maximum dimension of the second hole 24 in the width direction of the top patch 100 is H2. That is, the maximum dimension of the second hole 24 in the width direction of the detection layer 20 is H2.

[0129] The detection layer 20 may also have a fifth hole 25. The fifth hole 25 penetrates the detection layer 20 along its thickness direction. The fifth hole 25 and the second hole 24 are spaced apart along the length of the detection layer 20. The fifth hole 25 is coaxially aligned with and connected to the fourth hole 15 of the bottom layer 10, and is used for the passage of the electrode post. The maximum dimension of the fifth hole 25 along the length of the top patch 100 is Φ2. That is, the maximum dimension of the fifth hole 25 along the length of the detection layer 20 is Φ2.

[0130] Alternatively, the maximum dimension of the fifth hole 25 in the width direction of the top patch 100 is Φ2. That is, the maximum dimension of the fifth hole 25 in the width direction of the detection layer 20 is Φ2.

[0131] The fifth hole 25 can be two. The two fifth holes 25 are spaced apart along the length of the detection layer 20. One fifth hole 25 allows the positive electrode post to pass through. The other fifth hole 25 allows the negative electrode post to pass through. A second hole 24 is located between the two fifth holes 25.

[0132] Please refer to the following: Figure 5a , Figure 5b and Figure 8 , Figure 8 yes Figure 4 The diagram shows the structure of the top layer 30 of the top patch 100.

[0133] The top layer 30 is connected to the second surface 22 of the detection layer 20. The top layer 30 is made of a transparent or translucent material to facilitate observation of color changes on the detection layer 20. The top layer 30 can be made of materials such as polypropylene, polyethylene (PE), polyethylene terephthalate, or polyvinyl chloride (PVC).

[0134] The top layer 30 may be provided with a third positioning structure 31. The third positioning structure 31 protrudes from the surface of the top layer 30 away from the detection layer 20 and in the direction away from the battery cell 320. The protrusion direction of the third positioning structure 31 relative to the top layer 30 is the same as the protrusion direction of the first positioning structure 12 of the bottom layer 10 relative to the bottom layer 10, and also the same as the protrusion direction of the second positioning structure 23 of the detection layer 20 relative to the detection layer 20. The third positioning structure 31, the second positioning structure 23 of the detection layer 20, and the first positioning structure 12 of the bottom layer 10 are arranged opposite to each other in the thickness direction of the top patch 100. The third positioning structure 31 is used to help the top layer 30 and the detection layer 20 to be positioned and assembled, and also serves as a foolproof mechanism. The third positioning structure 31 and the top layer 30 can be connected to form an integrated structure.

[0135] The number of third positioning structures 31 can be one or more. This embodiment does not limit the shape of the third positioning structure 31 or its position on the top layer 30. When there are multiple third positioning structures 31, their shapes can be similar, identical, or different.

[0136] It is understandable that when there are multiple third positioning structures 31, the multiple third positioning structures 31 are set as symbols of different shapes, so that the third positioning structures 31 can be used as marking symbols to help the top layer 30 and the detection layer 20 to identify and assemble, and to prevent the top layer 30 and the detection layer 20 from being misaligned.

[0137] For one possible application scenario, please refer to [link / reference]. Figure 6 The top layer 30 is rectangular in shape. There can be two third positioning structures 31. The two third positioning structures 31 are spaced apart along the length direction (X direction in the diagram) of the top layer 30. The two third positioning structures 31 are also spaced apart along the width direction (Y direction in the diagram) of the top layer 30. Each third positioning structure 31 is located near a corner of the top layer 30. That is, the two third positioning structures 31 are located at opposite corners of the top layer 30. One of the third positioning structures 31 is shaped like a "+", and the other is shaped like a "-".

[0138] Understandably, by setting a third positioning structure 31 on the top layer 30, the top layer 30 and the detection layer 20 can be quickly positioned and assembled, improving production efficiency and preventing installation misalignment. At the same time, setting the two third positioning structures 31 to both "+" and "-" shapes can further improve the assembly accuracy between the top layer 30 and the detection layer 20.

[0139] In some other embodiments, the top layer 30 may not have a third positioning structure 31.

[0140] In this embodiment, the third positioning structure 31 may have a third cavity. The opening of the third cavity is located on the surface of the top layer 30 facing the detection layer 20. The third cavity is formed by recessing from the surface of the top layer 30 away from the detection layer 20 into the third positioning structure 31. The recess direction of the third cavity relative to the third positioning structure 31 is the same as the recess direction of the second cavity of the detection layer 20 relative to the second positioning structure 23, and also the same as the recess direction of the first cavity of the bottom layer 10 relative to the first positioning structure 12. The third cavity is used to accommodate the second positioning structure 23 of the detection layer 20 to achieve the connection between the top layer 30 and the detection layer 20.

[0141] In summary, the protrusion direction of the third positioning structure 31 of the top layer 30 relative to the top layer 30 is the same as the protrusion direction of the second positioning structure 23 of the detection layer 20 relative to the detection layer 20, and is also the same as the protrusion direction of the first positioning structure 12 of the bottom layer 10 relative to the bottom layer 10.

[0142] In one possible application scenario, the first positioning structure 12 of the bottom layer 10 protrudes away from the battery cell 320 relative to the surface of the bottom layer 10 facing the detection layer 20. The second positioning structure 23 of the detection layer 20 protrudes away from the battery cell 320 relative to the second surface 22. The third positioning structure 31 of the top layer 30 protrudes away from the battery cell 320 relative to the surface of the top layer 30 away from the detection layer 20. The first positioning structure 12 of the bottom layer 10 is located within the second cavity of the detection layer 20, achieving a positioning connection between the bottom layer 10 and the detection layer 20. The second positioning structure 23 of the detection layer 20 is located within the third cavity of the top layer 30, achieving a positioning connection between the detection layer 20 and the top layer 30.

[0143] In another possible application scenario, unlike the previous one, the first positioning structure 12 may not be provided on the bottom layer 10. The second positioning structure 23 of the detection layer 20 protrudes towards the battery cell 320 relative to the first surface 21. The third positioning structure 31 of the top layer 30 protrudes towards the battery cell 320 relative to the surface of the top layer 30 facing the detection layer 20. The second positioning structure 23 of the detection layer 20 abuts against the bottom layer 10, realizing the positioning connection between the detection layer 20 and the bottom layer 10. The third positioning structure 31 of the top layer 30 is located within the second cavity of the detection layer 20, realizing the positioning connection between the top layer 30 and the detection layer 20.

[0144] In this application scenario, a third cavity can be provided in the third positioning structure 31. The third cavity is recessed into the third positioning structure 31 from the surface of the top layer 30 away from the detection layer 20. Alternatively, the third positioning structure 31 may not have a third cavity.

[0145] Please see Figure 8 The top layer 30 may further include a second protruding structure 32. The second protruding structure 32 protrudes from the surface of the top layer 30 toward the detection layer 20 towards the cell 320. The second protruding structure 32 is positioned close to and spaced apart from the third positioning structure 31. The projection of the second protruding structure 32 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 is offset from the detection layer 20. That is, the projection of the detection layer 20 onto the top layer 30 along the thickness direction of the top patch 100 is offset from the second protruding structure 32. In other words, the second protruding structure 32 is located outside the outer edge of the detection layer 20. Specifically, the second protruding structure 32 may be spaced apart from the outer edge of the detection layer 20. The second protruding structure 32 may also abut against the outer edge of the detection layer 20. There are no limitations on this, as long as the second protruding structure 32 can position the detection layer 20 and prevent misalignment between the top layer 30 and the detection layer 20. The second protruding structure 32 and the top layer 30 can be connected to form an integral structure.

[0146] The number of second protruding structures 32 can be one or more. This embodiment does not limit the shape of the second protruding structures 32. When there are multiple second protruding structures 32, the shapes of the multiple second protruding structures 32 can be the same or different.

[0147] Understandably, by setting the second protrusion structure 32 on the top layer 30, not only can the movement of the detection layer 20 be prevented, enhancing the connection stability of the detection layer 20, but it can also help the top layer 30 and the detection layer 20 to be quickly positioned and assembled, improving production efficiency and preventing installation misalignment. At the same time, combining the second protrusion structure 32 and the third positioning structure 31 provides dual protection for the positioning and assembly between the top layer 30 and the detection layer 20, further improving the assembly accuracy between the top layer 30 and the detection layer 20.

[0148] In addition, in this embodiment, the projection of the second protrusion structure 32 onto the bottom layer 10 along the thickness direction of the top patch 100 can be offset from that of the first protrusion structure 13. For example, the second protrusion structure 32 and the first protrusion structure 13 can be located on the same diagonal of the top patch 100, respectively. Alternatively, the second protrusion structure 32 and the first protrusion structure 13 can be located on different diagonals of the top patch 100, respectively.

[0149] In one possible application scenario, please refer to the relevant documentation. Figure 4 and Figure 8 The top layer 30 is rectangular in shape. There can be two second protrusions 32. The two second protrusions 32 are spaced apart along the length of the top layer 30. The two second protrusions 32 are also spaced apart along the width of the top layer. Each second protrusion 32 is located near a corner of the top layer 30 and near a third positioning structure 31. That is, the two second protrusions 32 are located at opposite corners of the top layer 30. One of the second protrusions 32 is shaped like a "「". The other second protrusion 32 is shaped like a "」". The "「" shaped second protrusion 32 is near the "-" shaped third positioning structure 31. The "」" shaped second protrusion 32 is near the "+" shaped third positioning structure 31. Furthermore, the projections of the two second protrusions 32 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 are located outside the opposite corners of the detection layer 20, thus preventing movement of the detection layer 20.

[0150] In this application scenario, the bottom layer 10 can have two first protrusion structures 13. The two first protrusion structures 13 are located at opposite corners of the bottom layer 10. One of the first protrusion structures 13 is shaped like a "「". The other first protrusion structure 13 is shaped like a "」". The projections of the two first protrusion structures 13 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 are offset from the projections of the two second protrusion structures 32 onto the plane of the detection layer 20 along the thickness direction of the top patch 100.

[0151] Specifically, the projections of the two first protrusions 13 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 are located outside the two diagonally opposite corners of the detection layer 20. The projections of the two second protrusions 32 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 are located outside the other two diagonally opposite corners of the detection layer 20. That is, the projections of the two first protrusions 13 onto the plane of the detection layer 20 along the thickness direction of the top patch 100, and the projections of the two second protrusions 32 onto the plane of the detection layer 20 along the thickness direction of the top patch 100, are located outside the four corners of the detection layer 20.

[0152] Alternatively, the projections of the two first protrusions 13 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 are respectively located on the outer sides of two diagonally opposite corners in the detection layer 20. The projections of the two second protrusions 32 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 are also respectively located on the outer or inner sides of these two diagonally opposite corners in the detection layer 20. Furthermore, the projection of each second protrusion 32 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 is adjacent to and staggered with the projection of a first protrusion 13 located at the same corner onto the plane of the detection layer 20 along the thickness direction of the top patch 100.

[0153] In another possible application scenario, unlike the previous one, there is only one second protrusion structure 32. The second protrusion structure 32 is located at a corner of the top layer 30, near a third positioning structure 31. The shape of the second protrusion structure 32 is either a "「" shape or a "」" shape. The projection of the second protrusion structure 32 onto the plane of the detection layer 20 along the thickness direction of the top patch 100 is located outside a corner of the detection layer 20.

[0154] In this application scenario, there is only one first protrusion structure 13. The first protrusion structure 13 is located at a corner of the bottom layer 10. This corner is diagonally opposite to the corner of the top layer 30 where the second protrusion structure 32 is located. The shape of the first protrusion structure 13 is either a "「" shape or a "」" shape. The projection of the first protrusion structure 13 onto the plane of the detection layer 20 along the thickness direction of the top patch 100, and the projection of the second protrusion structure 32 onto the plane of the detection layer 20 along the thickness direction of the top patch 100, are respectively located outside the two diagonally opposite corners of the detection layer 20.

[0155] Of course, in other application scenarios, a second protruding structure 32 can be set on the top layer 30, and the first protruding structure 13 can be not set on the bottom layer 10. There are no strict restrictions on this.

[0156] Please refer to the following: Figure 4 and Figure 8 In this embodiment, the top layer 30 may have a third hole 33. The third hole 33 penetrates the top layer 30 along its thickness direction. The third hole 33 is coaxially arranged with the explosion-proof hole of the top cover 210, the first hole 14 of the bottom layer 10, and the second hole 24 of the detection layer 20. In the thickness direction of the top patch 100, the third hole 33 communicates with the first hole 14 of the bottom layer 10 through the second hole 24 of the detection layer 20. The third hole 33 is used to expose the explosion-proof valve. The maximum dimension of the third hole 33 in the length direction of the top patch 100 is D3. That is, the maximum dimension of the third hole 33 in the length direction of the top layer 30 is D3. The maximum dimension of the third hole 33 in the width direction of the top patch 100 is H3. That is, the maximum dimension of the third hole 33 in the width direction of the top layer 30 is H3.

[0157] In this embodiment, the maximum dimension D3 of the third hole 33 of the top layer 30 along the length of the top patch 100 satisfies the following relationship with the maximum dimension D1 of the first hole 14 of the bottom layer 10 along the length of the top patch 100 and the maximum dimension D2 of the second hole 24 of the detection layer 20 along the length of the top patch 100:

[0158] D1 = D3;

[0159] 10mm≥D2-D1≥2mm;

[0160] 10mm≥D2-D3≥2mm.

[0161] The maximum dimension H3 of the third hole 33 of the top layer 30 in the width direction of the top patch 100 satisfies the following relationship with the maximum dimension H1 of the first hole 14 of the bottom layer 10 in the width direction of the top patch 100 and the maximum dimension H2 of the second hole 24 of the detection layer 20 in the width direction of the top patch 100:

[0162] H1 = H3;

[0163] 10mm≥H2-H1≥2mm;

[0164] 10mm≥H2-H3≥2mm.

[0165] It is understood that in this embodiment, the bottom layer 10 and the top layer 30 are connected by heat fusion to the areas of the detection layer 20 that are adjacent to each other. Therefore, by making the maximum dimensions of the first hole 14 of the bottom layer 10 in the length and width directions of the top patch 100, and the maximum dimensions of the third hole 33 of the top layer 30 in the length and width directions of the top patch 100, both smaller than the maximum dimensions of the second hole 24 of the detection layer 20 in the length and width directions, the edge of the second hole 24 of the detection layer 20 can be covered by the bottom layer 10 and the top layer 30, thereby preventing the edge of the second hole 24 of the detection layer 20 from participating in the fusion during heat fusion, thus avoiding the problem of detection layer 20 failure.

[0166] Please refer to the following: Figure 4 and Figure 8 The top layer 30 may also have a sixth hole 34. The sixth hole 34 penetrates the top layer 30 along its thickness direction. The sixth hole 34 and the third hole 33 are spaced apart along the length of the top layer 30. The sixth hole 34 is coaxially arranged with the fifth hole 25 of the detection layer 20 and the fourth hole 15 of the bottom layer 10. The sixth hole 34 connects to the fourth hole 15 of the bottom layer 10 through the fifth hole 25 of the detection layer 20 and is used for the passage of the electrode post. The maximum dimension of the sixth hole 34 along the length of the top patch 100 is Φ3. That is, the maximum dimension of the sixth hole 34 along the length of the top layer 30 is Φ3.

[0167] Alternatively, the maximum dimension of the sixth hole 34 in the width direction of the top patch 100 is Φ3. That is, the maximum dimension of the sixth hole 34 in the width direction of the top layer 30 is Φ3.

[0168] The number of sixth holes 34 can be two. The two sixth holes 34 are spaced apart along the length of the top layer 30. One sixth hole 34 allows the positive terminal to pass through. The other sixth hole 34 allows the negative terminal to pass through. A third hole 33 is located between the two sixth holes 34.

[0169] In this embodiment, the maximum dimension of the sixth hole 34 of the top layer 30 along the length of the top patch 100 is Φ3, which satisfies the following relationship with the maximum dimension Φ1 of the fourth hole 15 of the bottom layer 10 along the length of the top patch 100 and the maximum dimension Φ2 of the fifth hole 25 of the detection layer 20 along the length of the top patch 100:

[0170] Φ1 = Φ3;

[0171] 8mm≥Φ2-Φ1≥2mm;

[0172] 8mm≥Φ2-Φ3≥2mm.

[0173] Alternatively, the maximum dimension of the sixth hole 34 of the top layer 30 in the width direction of the top patch 100 is Φ3, which satisfies the following relationship with the maximum dimension Φ1 of the fourth hole 15 of the bottom layer 10 in the width direction of the top patch 100 and the maximum dimension Φ2 of the fifth hole 25 of the detection layer 20 in the width direction of the top patch 100:

[0174] Φ1 = Φ3;

[0175] 8mm≥Φ2-Φ1≥2mm;

[0176] 8mm≥Φ2-Φ3≥2mm.

[0177] Understandably, by making the maximum dimensions of the fourth hole 15 of the bottom layer 10 in the length and width directions of the top patch 100, and the maximum dimensions of the sixth hole 34 of the top layer 30 in the length and width directions of the top patch 100, both smaller than the maximum dimensions of the fifth hole 25 of the detection layer 20 in the length and width directions of the top patch 100, the edge of the fifth hole 25 of the detection layer 20 can be covered by the bottom layer 10 and the top layer 30. This prevents the edge of the fifth hole 25 of the detection layer 20 from participating in the welding during heat fusion, thus avoiding the problem of detection layer 20 failure.

[0178] Understandably, battery manufacturing relies heavily on welding to connect multiple components. However, welding processes easily generate waste gases (such as carbon dioxide and hydrogen). These gases entering the weld seam can affect its strength, causing weaker welds to widen and leading to air / liquid leakage. However, current technology cannot promptly detect air and liquid leaks in the top cover assembly.

[0179] Therefore, in this embodiment, by enabling the detection layer 20 to change color upon contact with the electrolyte, when leakage occurs in the top cover assembly 200, the leaked electrolyte can penetrate through the bottom layer 10 to the detection layer 20, causing the detection layer 20 to change color and be identified by humans or machine vision, thus preventing continuous leakage. Furthermore, by observing the location of the color change on the detection layer 20 through the top layer 30, the location of leakage in the top cover assembly 200 can be pinpointed, such as leakage at the electrode post or at the explosion-proof valve.

[0180] Please see Figure 4 The top patch 100 may be provided with a mark 50. The mark 50 is used to identify the battery cell 320. The mark 50 may be located on the surface of the top layer 30 opposite to the detection layer 20. In the length direction of the top layer 30, the mark 50 is located between the third hole 33 and the sixth hole 34, and is spaced apart from both the third hole 33 and the sixth hole 34.

[0181] Understandably, placing the label 50 directly on the top patch 100 instead of on the top cover 210 reduces the exposed area of ​​the top cover 210, which helps to reduce the risk of leakage of the battery cell 320 and the casing 310.

[0182] Of course, in some other embodiments, the mark 50 may also be located on the second surface 22 of the detection layer 20, as long as the display of the mark 50 and the color change of the detection layer 20 do not interfere with each other. It is understood that since the top layer 30 is transparent or semi-transparent, the mark 50 can also be observed when it is located on the second surface 22 of the detection layer 20.

[0183] Please refer to the following: Figure 5a , Figure 5b and Figure 6 In this embodiment, the top patch 100 may further include an adhesive layer 40. The adhesive layer 40 connects the bottom layer 10 and the top cover 210, bonding the bottom layer 10 and the top cover 210 together. To ensure that the electrolyte can penetrate the bottom layer 10 and enter the detection layer 20, in this embodiment, the adhesive can be applied to the bottom layer 10 to form the adhesive layer 40 using the following two methods:

[0184] The first approach is to apply adhesive to the surface of the bottom layer 10 opposite to the detection layer 20 using a dispensing technique. During dispensing, the adhesive layer 40 formed by the adhesive should avoid the liquid guiding holes 11 on the bottom layer 10. That is, the adhesive layer 40 should fall along the thickness direction of the top patch 100 (Z direction in the diagram) into the projection of the bottom layer 10, and be offset from the liquid guiding holes 11 on the bottom layer 10. This avoids the adhesive clogging the liquid guiding holes 11, preventing the electrolyte from passing through the bottom layer 10 into the detection layer 20.

[0185] The second approach is to use a neutral or alkaline material for the adhesive layer 40. The adhesive layer 40 can cover the liquid-conducting holes 11 of the bottom layer 10. For example, the adhesive forming the adhesive layer 40 can be a polyurethane (PU) adhesive, an acrylic acid (AA) adhesive, a polyvinyl acetate (PVAc) adhesive, etc. Such adhesives can be dissolved or penetrated by the electrolyte, and the products after hydrolysis will not affect the detection results of the detection layer 20 on the electrolyte. It should be noted that the composition of the adhesive in this embodiment is not limited to this.

[0186] Understandably, even if the liquid guiding holes 11 on the bottom layer 10 are covered by the adhesive layer 40, as long as the amount of adhesive is not excessive enough to clog the liquid guiding holes 11, the electrolyte can penetrate or dissolve the adhesive layer. This allows the electrolyte to then enter the detection layer 20 through the bottom layer 10, causing a color change in the detection layer 20, thus detecting leakage in the top cover assembly 200. This significantly reduces the processing time for setting the adhesive layer 40 on the bottom layer 10, thereby improving the production efficiency of the battery 300.

[0187] In this embodiment, the assembly of the top patch 100 should be carried out in a dry environment, and the assembly method of the top patch 100 includes at least the following steps:

[0188] Step 1: Place the bottom layer 10 in the tooling.

[0189] Step 2: Place the detection layer 20 on the bottom layer 10, and position and assemble the detection layer 20 with the bottom layer 10 through the first positioning structure 12 of the bottom layer 10 and the second positioning structure 23 of the detection layer 20.

[0190] Step 3: Place the top layer 30 on the detection layer 20, and position and assemble the top layer 30 and the detection layer 20 through the second positioning structure 23 of the detection layer 20 and the third positioning structure 31 of the top layer 30.

[0191] Step 4: Connect the areas of the bottom layer 10 and the top layer 30 with the additional detection layer 20 by heat fusion, so as to fix the detection layer 20 between the bottom layer 10 and the top layer 30.

[0192] Step 5: Form an adhesive layer 40 on the surface of the bottom layer 10 facing away from the detection layer 20, and bond the adhesive layer 40 to the top cover 210.

[0193] Second embodiment:

[0194] Please see Figure 9 , Figure 9 This is another structural schematic diagram of the top patch 100 provided in the embodiments of this application.

[0195] In this embodiment, the contents that are the same as in the first embodiment will not be repeated. The difference from the first embodiment is that the mark 50 is disposed on the top cover 210, and a first through hole 60 is provided on the top patch 100 to expose the mark 50 on the top cover 210. In addition, the description of the top patch 100 below can be applied to the first embodiment above unless otherwise specified.

[0196] The top patch 100 may have a first through hole 60. The first through hole 60 penetrates the bottom layer 10 and the detection layer 20 along the thickness direction of the top patch 100. The first through hole 60 may communicate with the first hole 14 of the bottom layer 10 and the second hole 24 of the detection layer 20. Alternatively, the first through hole 60 may be spaced apart from the first hole 14 of the bottom layer 10 and the second hole 24 of the detection layer 20. In some other embodiments, the first through hole 60 may also penetrate the entire top patch 100 along the thickness direction of the top patch 100. That is, the first through hole 60 may penetrate the bottom layer 10, the detection layer 20, and the top layer 30 along the thickness direction of the top patch 100.

[0197] Understandably, by providing a first through hole 60 on the top patch 100, the marking 50 on the top cover 210 can be exposed for the identification of the cell 320 during the manufacturing process of the battery 300.

[0198] Please refer to the following: Figure 9 , Figure 10 and Figure 11 , Figure 10 yes Figure 9 The diagram shows the structure of the bottom layer 10 of the top patch 100. Figure 11 yes Figure 9 The diagram shows the structure of the detection layer 20 of the top patch 100.

[0199] In this embodiment, the first through hole 60 may include a seventh hole 61 and an eighth hole 62. The seventh hole 61 and the eighth hole 62 are coaxially arranged and connected. The seventh hole 61 penetrates the bottom layer 10 along its thickness direction. In the length direction of the bottom layer 10, the seventh hole 61 may be connected to the first hole 14 of the bottom layer 10 and is spaced apart from the fourth hole 15 of the bottom layer 10. The seventh hole 61 is used to expose the mark 50 on the top cover 210. The maximum dimension of the seventh hole 61 in the length direction of the top patch 100 is d1. That is, the maximum dimension of the seventh hole 61 in the length direction of the bottom layer 10 is d1. The maximum dimension of the seventh hole 61 in the width direction of the top patch 100 is h1. The maximum dimension of the seventh hole 61 in the width direction of the bottom layer 10 is h1.

[0200] In some other embodiments, the seventh hole 61 may also be spaced apart from the first hole 14 and the fourth hole 15 of the bottom layer 10 along the length direction of the bottom layer 10.

[0201] The eighth hole 62 penetrates the detection layer 20 along its thickness direction. Along the length of the detection layer 20, the eighth hole 62 can communicate with the second hole 24 of the detection layer 20 and is spaced apart from the fifth hole 25 of the detection layer 20. The eighth hole 62 is used to expose the mark 50 on the top cover 210. The maximum dimension of the eighth hole 62 along the length of the top patch 100 is d2. That is, the maximum dimension of the eighth hole 62 along the length of the detection layer 20 is d2. The maximum dimension of the eighth hole 62 along the width of the top patch 100 is h2. That is, the maximum dimension of the eighth hole 62 along the width of the detection layer 20 is h2.

[0202] In some other embodiments, the eighth hole 62 may also be spaced apart from the second hole 24 and the fifth hole 25 of the detection layer 20 along the length of the detection layer 20.

[0203] Understandably, by providing the first through-hole 60 on the bottom layer 10 and the detection layer 20 of the top patch 100, the marking 50 on the top cover 210 can be exposed, so that the coding of the cell 320 can be confirmed during the manufacturing process of the battery 300 through the transparent or semi-transparent top layer 30. Furthermore, since the top layer 30 seals one side of the opening of the first through-hole 60, it helps to reduce the exposed area of ​​the top cover 210, which is beneficial to reducing the risk of leakage of the cell 320 and the casing 310.

[0204] In this embodiment, the maximum dimension d1 of the seventh hole 61 along the length of the top patch 100 and the maximum dimension d2 of the eighth hole 62 along the length of the top patch 100 satisfy the following relationship:

[0205] 6mm≥d2-d1≥1mm.

[0206] The maximum dimension h1 of the seventh hole 61 in the width direction of the top patch 100 and the maximum dimension h2 of the eighth hole 62 in the width direction of the top patch 100 satisfy the following relationship:

[0207] 6mm≥h2-h1≥1mm.

[0208] Understandably, by making the maximum dimensions of the eighth hole 62 on the detection layer 20 in both the length and width directions of the top patch 100 larger than the maximum dimensions of the seventh hole 61 on the bottom layer 10 in both the length and width directions of the top patch 100, the edge of the eighth hole 62 on the detection layer 20 can be covered by the bottom layer 10 and the top layer 30. This prevents the edge of the eighth hole 62 on the detection layer 20 from participating in the welding process during heat fusion, thus avoiding the problem of detection layer 20 failure. Furthermore, it keeps the detection layer 20 in a relatively sealed environment, making it less susceptible to external environmental influences and contributing to the long-term stability of the detection function of the detection layer 20.

[0209] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A top patch, characterized in that, The top patch comprises a bottom layer, a detection layer, and a top layer stacked sequentially. The bottom layer is provided with a plurality of liquid guiding holes, which are spaced apart on the bottom layer. Each liquid guiding hole penetrates the bottom layer along the thickness direction of the bottom layer. The bottom layer is used to connect with the top cover. The detection layer includes a first surface and a second surface, which are disposed opposite to each other in the thickness direction of the detection layer. The first surface is connected to the bottom layer and covers a plurality of liquid guiding holes. The second surface is connected to the top layer. The detection layer is used to change color when in contact with electrolyte, and the top layer is used to observe the color change of the detection layer. The bottom layer has a first hole that penetrates the bottom layer along its thickness direction. The detection layer has a second hole that penetrates the detection layer along its thickness direction. The top layer has a third hole that penetrates the top layer along its thickness direction. The first hole, the second hole, and the third hole are sequentially connected and coaxially arranged. The first hole, the second hole, and the third hole are used to expose the explosion-proof valve. The first hole is staggered from the plurality of liquid guiding holes.

2. The top patch according to claim 1, characterized in that, The top patch also includes an adhesive layer, which is connected between the bottom layer and the top cover. The adhesive layer falls into the projection of the bottom layer along the thickness direction of the top patch and is offset from the plurality of liquid guiding holes.

3. The top patch according to claim 1, characterized in that, The top patch also includes an adhesive layer, which is connected between the bottom layer and the top cover. The adhesive layer covers a plurality of the liquid guiding holes, and the material of the adhesive layer is a neutral material or an alkaline material.

4. The top patch according to any one of claims 1-3, characterized in that, The top layer is made of a transparent or semi-transparent material.

5. The top patch according to any one of claims 1-3, characterized in that, The bottom layer is provided with a first positioning structure, the detection layer is provided with a second positioning structure, and the top layer is provided with a third positioning structure. The first positioning structure and the second positioning structure are arranged opposite to each other in the thickness direction of the top patch, and the third positioning structure and the second positioning structure are arranged opposite to each other in the thickness direction of the top patch. At least a portion of the first positioning structure is located within the second positioning structure, and at least a portion of the second positioning structure is located within the third positioning structure; or... At least a portion of the second positioning structure is located within the first positioning structure, and at least a portion of the third positioning structure is located within the second positioning structure.

6. The top patch according to any one of claims 1-3, characterized in that, The bottom layer has a first protruding structure, which protrudes from the surface of the bottom layer toward the detection layer. The projection of the detection layer onto the bottom layer along the thickness direction of the top patch is offset from the first protruding structure; and / or The top layer is provided with a second protruding structure, which protrudes from the surface of the top layer toward the detection layer. The projection of the detection layer on the top layer along the thickness direction of the top patch is offset from the second protruding structure.

7. The top patch according to any one of claims 1-3, characterized in that, The outer edge of the bottom layer is also connected to the outer edge of the top layer to enclose the detection layer in the top layer and the bottom layer.

8. The top patch according to claim 7, characterized in that, The maximum dimension L1 of the bottom layer in the length direction of the top patch, the maximum dimension L2 of the detection layer in the length direction of the top patch, and the maximum dimension L3 of the top layer in the length direction of the top patch satisfy the following relationship: L1=L3; 10mm ≥ L1 - L2 ≥ 2mm; 10mm≥L3-L2≥2mm.

9. The top patch according to claim 7, characterized in that, The maximum dimension W1 of the bottom layer in the width direction of the top patch, the maximum dimension W2 of the detection layer in the width direction of the top patch, and the maximum dimension W3 of the top layer in the width direction of the top patch satisfy the following relationship: W1=W3; 10mm≥W1-W2≥2mm; 10mm≥W3-W2≥2mm.

10. The top patch according to claim 7, characterized in that, The maximum dimensions D1 of the first hole, D2 of the second hole, and D3 of the third hole in the length direction of the top patch satisfy the following relationship: D1=D3; 10mm≥D2-D1≥2mm; 10mm≥D2-D3≥2mm.

11. The top patch according to claim 10, characterized in that, The maximum dimensions H1 of the first hole in the width direction of the top patch, the maximum dimensions H2 of the second hole in the width direction of the top patch, and the maximum dimensions H3 of the third hole in the width direction of the top patch satisfy the following relationship: H1=H3; 10mm≥H2-H1≥2mm; 10mm≥H2-H3≥2mm.

12. The top patch according to claim 10, characterized in that, The bottom layer has a fourth hole that penetrates the bottom layer along its thickness direction. The fourth hole and the first hole are spaced apart along the length direction of the bottom layer. The detection layer has a fifth hole that penetrates the detection layer along its thickness direction. The fifth hole and the second hole are spaced apart along the length direction of the detection layer. The top layer has a sixth hole that penetrates the top layer along its thickness direction. The sixth hole and the third hole are spaced apart along the length direction of the top layer. The fourth hole, the fifth hole, and the sixth hole are sequentially connected and coaxially arranged. The fourth hole, the fifth hole, and the sixth hole are used for the passage of the electrode post. The maximum dimensions Φ1 of the fourth hole, Φ2 of the fifth hole, and Φ3 of the sixth hole in the length direction of the top patch satisfy the following relationship: Φ1=Φ3; 8mm≥Φ2-Φ1≥2mm; 8mm≥Φ2-Φ3≥2mm.

13. The top patch according to any one of claims 1-3, characterized in that, The top patch also includes an identifier, which is located on the surface of the top layer opposite to the detection layer.

14. The top patch according to any one of claims 1-3, characterized in that, The bottom layer has a seventh hole that penetrates the bottom layer along its thickness direction. The detection layer has an eighth hole that penetrates the detection layer along its thickness direction. The seventh hole and the eighth hole are coaxially arranged and connected. The seventh hole and the eighth hole are used to expose the markings on the top cover.

15. The top patch according to claim 14, characterized in that, The maximum dimension d1 of the seventh hole and the maximum dimension d2 of the eighth hole in the length direction of the top patch satisfy the following relationship: 6mm≥d2-d1≥1mm.

16. The top patch according to claim 14, characterized in that, The maximum dimension h1 of the seventh hole in the width direction of the top patch and the maximum dimension h2 of the eighth hole in the width direction of the top patch satisfy the following relationship: 6mm≥h2-h1≥1mm.

17. A top cover assembly, characterized in that, The top cover assembly includes a top cover and a top patch as described in any one of claims 1-16, the top cover being attached to the bottom layer.

18. A battery, characterized in that, The battery includes the top cover assembly as described in claim 17.

19. An electrical appliance, characterized in that, The electrical device includes the battery as described in claim 18.

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