Top patch, top cover assembly, battery and electric equipment

Abstract

The invention provides a top patch, a top cover assembly, a battery and electric equipment. The top patch comprises a bottom layer, a detection layer and a top layer which are stacked in sequence; the bottom layer is provided with a plurality of liquid guide holes, the liquid guide holes are formed in the bottom layer at intervals, each liquid guide hole penetrates through the bottom layer in the thickness direction of the bottom layer, and the bottom layer is used for being connected with a 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 multiple liquid guide holes, the second surface is connected with the top layer, and the top layer is connected with the detection layer. The color of the detection layer changes when the detection layer is in contact with electrolyte, and the top layer is used for observing the color change of the detection layer. According to the technical scheme, the liquid leakage detection capacity in the top cover assembly can be improved, and continuous liquid leakage of the battery is avoided.

Description

Technical Field

[0001] The present 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 Art

[0002] With the development of green energy and the enhancement of people's environmental awareness, the application of recyclable batteries is becoming more and more widespread. At present, batteries rely on welding to achieve the combination of multiple components during the production and manufacturing process. However, the exhaust gas generated during the welding process easily enters the weld and then affects the strength of the weld, causing the battery to leak gas and liquid. However, in the prior art, the leakage of gas and liquid in the top cover assembly cannot be discovered in time. Summary of the invention

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

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

[0005] The bottom layer is provided with a plurality of liquid guide holes, which are arranged at intervals on the bottom layer, and each of the liquid guide holes penetrates the bottom layer along the thickness direction of the bottom layer, and the bottom layer is used to be connected to the top cover;

[0006] The detection layer includes a first surface and a second surface, the first surface and the second surface are arranged relative 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 the liquid guide holes, the second surface is connected to the top layer, the detection layer is used to change color when in contact with the electrolyte, and the top layer is used to observe the color change of the detection layer.

[0007] It is understandable that during the manufacturing process of batteries, multiple components are connected by welding. However, waste gas (such as carbon dioxide and hydrogen) is easily generated during the welding process. The waste gas entering the weld will affect the strength of the weld, causing the gap at the weaker weld to become larger, and then causing the battery to leak gas / liquid. However, in the prior art, it is still impossible to detect the leakage of gas and liquid in the top cover assembly in a timely manner.

[0008] Therefore, in this embodiment, by making the detection layer change color when in contact with the electrolyte, when the top cover assembly leaks, the leaked electrolyte can penetrate into the detection layer through the bottom layer, thereby causing the detection layer to change color and be visually recognized by humans or machines, thereby avoiding continuous leakage. In addition, by observing the position where the color changes on the detection layer through the top layer, the position where the leakage occurs in the top cover assembly can also be located.

[0009] In a possible implementation, the top patch further includes an adhesive layer, the adhesive layer 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 staggered with the plurality of liquid guide holes.

[0010] In a possible implementation, the top patch further includes an adhesive layer, the adhesive layer is connected between the bottom layer and the top cover, the adhesive layer covers the plurality of liquid guide holes, and the material of the adhesive layer is a neutral material or an alkaline material.

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

[0012] In a possible implementation manner, 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;

[0013] At least part of the first positioning structure is located in the second positioning structure, and at least part of the second positioning structure is located in the third positioning structure; or,

[0014] At least part of the second positioning structure is located in the first positioning structure, and at least part of the third positioning structure is located in the second positioning structure.

[0015] In a possible implementation manner, the bottom layer is provided with a first protruding structure, the first protruding structure is protruding relative to the bottom layer toward the surface of the detection layer, and the projection of the detection layer on the bottom layer along the thickness direction of the top patch is staggered with the first protruding structure; and / or,

[0016] The top layer is provided with a second protruding structure, which is protruding relative to the top layer toward the surface of 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 a possible implementation manner, the outer edge of the bottom layer is also connected to the outer edge of the top layer, so that the detection layer is enclosed in the top layer and the bottom layer.

[0018] In a possible implementation manner, 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 relationship:

[0019] L1=L3;

[0020] 10mm≥L1-L2≥2mm;

[0021] 10mm≥L3-L2≥2mm.

[0022] In a possible implementation manner, 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 relationship:

[0023] W1=W3;

[0024] 10mm≥W1-W2≥2mm;

[0025] 10mm≥W3-W2≥2mm.

[0026] In a possible implementation manner, the bottom layer is provided with a first hole, the first hole penetrates the bottom layer along the thickness direction of the bottom layer, the detection layer is provided with a second hole, the second hole penetrates the detection layer along the thickness direction of the detection layer, the top layer is provided with a third hole, the third hole penetrates the top layer along the thickness direction of the top layer, 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 dimension D1 of the first hole in the length direction of the top patch, the maximum dimension D2 of the second hole in the length direction of the top patch, and the maximum dimension D3 of the third hole in the length direction of the top patch satisfy the relationship:

[0028] D1=D3;

[0029] 10mm≥D2-D1≥2mm;

[0030] 10mm≥D2-D3≥2mm.

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

[0032] H1=H3;

[0033] 10mm≥H2-H1≥2mm;

[0034] 10mm≥H2-H3≥2mm.

[0035] In a possible implementation manner, the bottom layer is provided with a fourth hole, the fourth hole penetrates the bottom layer along the thickness direction of the bottom layer, the fourth hole and the first hole are spaced apart in the length direction of the bottom layer, the detection layer is provided with a fifth hole, the fifth hole penetrates the detection layer along the thickness direction of the detection layer, the fifth hole and the second hole are spaced apart in the length direction of the detection layer, the top layer is provided with a sixth hole, the sixth hole penetrates the top layer along the thickness direction of the top layer, the sixth hole and the third hole are spaced apart in 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 pole to pass through;

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

[0037] Φ1=Φ3;

[0038] 8mm≥Φ2-Φ1≥2mm;

[0039] 8mm≥Φ2-Φ3≥2mm.

[0040] In a possible implementation manner, the top patch further includes a logo, and the logo is disposed on a surface of the top layer facing away from the detection layer, or the logo is disposed on the detection layer and located between the detection layer and the top layer.

[0041] In a possible implementation, the bottom layer is provided with a seventh hole, the seventh hole penetrates the bottom layer along the thickness direction of the bottom layer, the detection layer is provided with an eighth hole, the eighth hole penetrates the detection layer along the thickness direction of the detection layer, the seventh hole is coaxially arranged and connected to the eighth hole, and the seventh hole and the eighth hole are used to expose the logo of the top cover.

[0042] In a possible implementation manner, 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 relationship:

[0043] 6mm≥d2-d1≥1mm.

[0044] In a possible implementation manner, 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 relationship:

[0045] 6mm≥h2-h1≥1mm.

[0046] In a second aspect, the present application also provides a top cover assembly, comprising a top cover and the top patch as described above, wherein the top cover is connected to the bottom layer.

[0047] In a third aspect, the present application also provides a battery, comprising the top cover assembly as described above.

[0048] In a fourth aspect, the present application also provides an electrical device, wherein the electrical device comprises the battery as described above. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0050] Figure 2 is a structural schematic diagram of a battery provided in an embodiment of the present application;

[0051] Figure 3 It is a structural schematic diagram of a part of the structure of the top cover assembly provided in an embodiment of the present application;

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

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

[0054] Figure 5b yes Figure 5a Enlarged view of middle area B;

[0055] Figure 6 yes Figure 4 A schematic diagram of the structure of the bottom layer of the top patch shown;

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

[0057] Figure 8 yes Figure 4 A schematic diagram of the structure of the top layer of the top patch shown;

[0058] Fig. 9 is another structural schematic diagram of a top patch provided in an embodiment of the present application;

[0059] Fig.10 yes Fig. 9 A schematic diagram of the structure of the bottom layer of the top patch shown;

[0060] Fig.11 yes Fig. 9 Schematic diagram of the structure of the detection layer of the top patch shown.

[0061] Reference numerals:

[0062] Energy storage system 500, electric energy conversion device 510, first user load 520, second user load 530, electric device 400, battery 300, shell 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 guide hole 11, first positioning structure 12, first protruding 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 The first through hole 60, the seventh hole 61, the eighth hole 62, the maximum dimension L1 of the bottom layer 10 in the length direction of the top patch 100, the maximum dimension W1 of the bottom layer 10 in the width direction of the top patch 100, the maximum dimension L2 of the detection layer 20 in the length direction of the top patch 100, the maximum dimension W2 of the detection layer 20 in the width direction of the top patch 100, the maximum dimension L3 of the top layer 30 in the length direction of the top patch 100, the maximum dimension L4 of the top layer 30 The maximum dimension W3 in the width direction of the top patch 100, the maximum dimension D1 of the first hole 14 in the length direction of the top patch 100, the maximum dimension H1 of the first hole 14 in the width direction of the top patch 100, the maximum dimension Φ1 of the fourth hole 15 in the length direction of the top patch 100, the maximum dimension D2 of the second hole 24 in the length direction of the top patch 100, the maximum dimension H2 of the second hole 24 in the width direction of the top patch 100, the maximum dimension Φ2 of the fifth hole 25 in the length direction of the top patch 100, and the maximum dimension Φ3 of the third hole 33 The maximum dimension D3 in the length direction of the top patch 100, the maximum dimension H3 of the third hole 33 in the width direction of the top patch 100, the maximum dimension Φ3 of the sixth hole 34 in the length direction of the top patch 100, the maximum dimension d1 of the seventh hole 61 in the length direction of the top patch 100, the maximum dimension h1 of the seventh hole 61 in the width direction of the top patch 100, the maximum dimension d2 of the eighth hole 62 in the length direction of the top patch 100, the maximum dimension h2 of the eighth hole 62 in the width direction of the top patch 100, and the hot melt zone S. DETAILED DESCRIPTION

[0063] For ease of understanding, the terms involved in the embodiments of the present application are first explained.

[0064] And / or: It is just a way to describe the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0065] Multiple: refers to two or more than two.

[0066] Connection: should be understood in a broad sense. For example, A and B are connected, which can be either direct or indirect through an intermediary.

[0067] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. It should be noted that the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0068] The embodiments of the present application provide a top patch, a top cover assembly, a battery and an electrical device.

[0069] Since the energy people need is highly temporal and spatial, in order to rationally utilize energy and improve energy utilization, it is necessary to use a medium or device to store one form of energy in the same form or convert it into another form of energy, and then release it in a specific form of energy based on future application needs. As we all know, the current generation of green electricity generally relies on photovoltaics, wind power, water potential, etc., while wind and solar energy generally have problems of strong intermittency and volatility, which will cause instability of the power grid, insufficient electricity during peak hours, too much electricity during low hours, and unstable voltage will also cause damage to electricity. Therefore, it may cause "wind and light abandonment" problems due to insufficient electricity demand or insufficient grid acceptance capacity. To solve these problems, energy storage must be relied on. That is, electrical energy is converted into other forms of energy by physical or chemical means and stored, and energy is converted into electrical energy and released when needed. In simple terms, energy storage is similar to a large "power bank". When photovoltaic and wind energy are sufficient, electrical energy is stored and the stored electricity is released when needed.

[0070] Taking electrochemical energy storage as an example, an embodiment of the present application provides an electrical device 400, which has a group of chemical batteries inside. The chemical elements in the chemical batteries are mainly used as energy storage media. The charging and discharging process is accompanied by chemical reactions or changes in the energy storage media. Simply put, the electricity generated by wind and solar energy is stored in chemical batteries. When the use of external electricity reaches a peak, the stored electricity is released for use, or transferred to places where electricity is scarce for use.

[0071] At present, energy storage application scenarios are quite extensive, including power 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 400 include:

[0072] Large-scale 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, achieve load matching of electricity in time and space, enhance the ability to absorb renewable energy, and are of great significance in grid system backup, alleviating peak load power supply pressure, and peak and frequency regulation.

[0073] The main operating mode of small and medium-sized energy storage cabinets used in industrial and commercial energy storage scenarios on the user side and small household energy storage boxes used in home energy storage scenarios on the user side is "peak shaving and valley filling". Since there are large price differences in electricity charges at peak and valley locations according to electricity demand, after users have electrical equipment 400, in order to reduce costs, they usually charge the energy storage cabinet / box during the low electricity price period; during the peak electricity price period, the electricity in the electrical equipment 400 is discharged for use, so as to save electricity bills. In addition, in remote areas, as well as areas prone to natural disasters such as earthquakes and hurricanes, the presence of household electrical equipment 400 is equivalent to users providing themselves and the power grid with backup power, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.

[0074] See also Figure 1 , Figure 1 4 is a schematic diagram of the structure of the energy storage system 500 provided in the embodiment of the present application. The embodiment of the present application takes the household energy storage scenario in the user-side energy storage as an example for explanation, and the electric device 400 of the present application is not limited to the household energy storage scenario.

[0075] The embodiment of the present application provides an energy storage system 500, which includes an electric energy conversion device 510, a first user load 520, a second user load 530, and an electric device 400. The electric device 400 is a small energy storage box that can be mounted on an outdoor wall by wall-mounting. Specifically, the photovoltaic panel can convert solar energy into electric energy during the period of low electricity prices. The electric device 400 is used to store the electric energy and supply it to street lamps and household appliances for use during the peak electricity prices, or to supply power when the power grid is out of power / power outage.

[0076] Among them, the electric device 400 may include but is not limited to single cells, battery modules, battery packs, battery systems, etc. When the electric device 400 includes multiple batteries, the multiple batteries are electrically connected and are all located inside the shell of the electric device 400, which can be protected from interference from the external environment under the protection of the shell. Exemplarily, multiple batteries are arranged at intervals. Multiple batteries can be connected in series, or in parallel, or a mixture of series and parallel connections to achieve greater capacity and power. The embodiments of the present application are described by taking the electric device 400 including a battery as an example, but it should be understood that the electric device 400 is not limited to this.

[0077] See also Figure 2 , Figure 2It is a structural schematic diagram of a battery 300 provided in an embodiment of the present application.

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

[0079] The battery 300 may include a top cover assembly 200, a shell 310 and a battery cell 320. The top cover assembly 200 is connected to the shell 310 and is surrounded by the shell 310 to form a receiving space, and the battery cell 320 is located in the receiving space. Exemplarily, the top cover assembly 200 may be welded to the shell 310 by welding. The shell 310 may be made of a metal material, such as an aluminum alloy. The battery 300 may be a cylindrical battery 300 or a square battery 300, etc.

[0080] It should be noted that Figure 2 The purpose of the above description is only to schematically describe the connection relationship between the top cover assembly 200, the housing 310 and the battery cell 320, and it does not specifically limit the connection position, specific structure and quantity of each device. The structure shown in the embodiment of the present application does not constitute a specific limitation on the battery 300. In other embodiments of the present application, the battery 300 may include Figure 2 More or fewer components may be shown, or some components may be combined or separated, or the components may be arranged differently. Figure 2 The components shown may be implemented in hardware, software or a combination of software and hardware.

[0081] Please refer to Figure 2 and Figure 3 , Figure 3 It is a structural schematic diagram of a partial structure of the top cover assembly 200 provided in an embodiment of the present application.

[0082] The top cover assembly 200 may include a top patch 100, a top cover 210, an explosion-proof valve (not shown) and a pole (not shown). The top cover 210 may be connected to the housing 310 to form a storage space for the battery 300. The top cover 210 may be provided with an explosion-proof hole. The explosion-proof hole penetrates the top cover 210 along the thickness direction of the top cover 210. The explosion-proof valve is connected to the explosion-proof hole on the top cover 210 and is used to achieve pressure relief protection of the battery 300. The top patch 100 is connected to the side of the top cover 210 away from the housing 310. The pole is penetrated by the top patch 100 and the top cover 210, and can be used as an electrode lead of the battery 300.

[0083] The number of the poles may be two. The two poles are spaced apart in the length direction of the top cover 210. The two poles are respectively a positive pole and a negative pole.

[0084] It should be noted that Figure 3 The purpose is only to schematically describe the connection relationship between the top patch 100 and the top cover 210, and it does not specifically limit the connection position, specific structure and quantity of each device. The structure illustrated in the embodiment of the present application does not constitute a specific limitation on the top cover assembly 200. In other embodiments of the present application, the top cover assembly 200 may include Figure 3 More or fewer components may be shown, or some components may be combined or separated, or the components may be arranged differently. Figure 3 The components shown may be implemented in hardware, software or a combination of software and hardware.

[0085] It is understandable that secondary batteries are a type of battery with great development potential. They are widely used in electronic products, electric vehicles, power grids and other equipment due to their advantages such as long cycle life, high specific energy, low self-discharge and no memory effect. In the manufacturing process, batteries mostly rely on welding to connect multiple components. For example, the connection between the top cover and the pole, the connection between the top cover and the shell, and the connection between the top cover and the sealing nail. However, waste gas (such as carbon dioxide and hydrogen) is generated during the welding of the battery, and the waste gas may enter the weld and affect the strength of the weld. In the subsequent module assembly and long-term battery charging and discharging process, the weaker welds are prone to larger gaps, resulting in gas leakage / liquid leakage in the battery. In addition, the sealing performance at the pole is currently mainly provided by the compression of the sealing ring. If there is a problem with the incoming material of the sealing ring or the compression of the sealing ring is reduced due to welding / high temperature, there is also the possibility of gas leakage / liquid leakage of the battery cell. In addition, many tests in the GB-T36276-2023 standard for lithium-ion batteries for power energy storage require that the battery cell "does not rupture at a location other than the explosion-proof valve or pressure relief point" after the test is completed. Therefore, it is very important to promptly detect whether there is leakage in the top cover assembly of the battery.

[0086] Therefore, the embodiment of the present application provides a top patch 100, which can improve the leakage detection capability in the top cover assembly 200 and prevent the battery 300 from continuously leaking. The structure of the top patch 100 will be described in detail below through two specific embodiments.

[0087] First embodiment:

[0088] Please refer to Figure 4 , Figure 5a and Figure 5b , Figure 4 is a schematic structural diagram of a top patch 100 provided in an embodiment of the present application, Figure 5a is along Figure 4 A schematic cross-sectional view of the top patch 100 obtained by cutting along the cutting line AA shown in FIG. Figure 5b yes Figure 5a Magnified view of area B in the middle.

[0089] The top patch 100 may include a bottom layer 10, a detection layer 20 and a top layer 30 which are stacked in sequence. 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 which is away from the top cover 210. The top layer 30 is connected to the surface of the detection layer 20 which is away from the bottom layer 10. The present embodiment does not limit the shapes of the bottom layer 10, the detection layer 20 and the top layer 30, as long as the bottom layer 10, the detection layer 20 and the top layer 30 can be connected correspondingly. Exemplarily, the shapes of the bottom layer 10, the detection layer 20 and the top layer 30 are all rectangular. Or, the shapes of the bottom layer 10, the detection layer 20 and the top layer 30 are all circular.

[0090] The sizes 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. After the size of the battery 300 is determined, their sizes meet the following relationship:

[0091] The maximum dimension L1 of the bottom layer 10 in the length direction (X direction in the figure) of the top patch 100, 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 relationship:

[0092] L1=L3;

[0093] 10mm≥L1-L2≥2mm;

[0094] 10mm≥L3-L2≥2mm.

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

[0096] W1=W3;

[0097] 10mm≥W1-W2≥2mm;

[0098] 10mm≥W3-W2≥2mm.

[0099] It can be understood that by making the maximum dimensions of the detection layer 20 in the length and width directions of the top patch 100 smaller than the maximum dimensions of the bottom layer 10 in the length and width directions of the top patch 100, and smaller than the maximum dimensions of the top layer 30 in the length and width directions of the top patch 100, the outer edge of the bottom layer 10 can be connected to the outer edge of the top layer 30, so that the detection layer 20 is completely covered in the bottom layer 10 and the top layer 30. The detection layer 20 is placed in a relatively sealed environment, thereby ensuring that the detection layer 20 is not easily affected by the external environment, which is conducive to maintaining the stability of the detection function of the detection layer 20 for a long time.

[0100] In this example, see Figure 4 The bottom layer 10 and the top layer 30 with the extra detection layer 20 (such as Figure 4 As shown in the shaded area in the figure, the hot melt zone S) is connected.

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

[0102] The bottom layer 10 may be provided with a plurality of liquid conducting holes 11. The plurality of liquid conducting holes 11 are arranged at intervals on the bottom layer 10. Each liquid conducting hole 11 penetrates the bottom layer 10 along the thickness direction of the bottom layer 10 (Z direction shown in the figure). The liquid conducting hole 11 is used for electrolyte to pass through. The size of the liquid conducting hole 11 can be selected according to the size of the battery cell 320 and the effect of leakage detection of the top patch 100. In the present embodiment, the size of the liquid conducting hole 11 can be in the range of 0.05mm-1mm (including the endpoint values ​​0.05mm and 1mm). Exemplarily, the plurality of liquid conducting 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 is protruded relative to the surface of the bottom layer 10 facing the detection layer 20 in the direction away from the battery cell 320. The first positioning structure 12 is used to help the bottom layer 10 and the detection layer 20 to be positioned and assembled, and to play a fool-proof role. The first positioning structure 12 and the bottom layer 10 may be connected to form an integrated structure. Exemplarily, the first positioning structure 12 may be connected to the bottom layer 10 by stamping to form an integrated structure. Alternatively, the first positioning structure 12 and the bottom layer 10 may also be an integrated structure formed by connecting by assembly methods such as welding and bonding. It should be noted that the integrated structures described below can all be connected by assembly methods such as stamping, welding, bonding, etc., which will not be repeated.

[0104] The number of the first positioning structures 12 may be one or more. This embodiment does not limit the shape of the first positioning structures 12 and the position of the first positioning structures 12 on the bottom layer 10. When the number of the first positioning structures 12 is multiple, the shapes of the multiple first positioning structures 12 may be similar, identical or different.

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

[0106] For a possible application scenario, see Figure 6 , the shape of the bottom layer 10 is a rectangle. The number of the first positioning structures 12 can be two. The two first positioning structures 12 are spaced apart in the length direction of the bottom layer 10 (the X direction in the figure). The two first positioning structures 12 are also spaced apart in the width direction of the bottom layer 10 (the Y direction in the figure). Each first positioning structure 12 is close to a corner of the bottom layer 10. That is, the two first positioning structures 12 are respectively located at two diagonal corners of the bottom layer 10. One of the first positioning structures 12 is in the shape of a "+". The other first positioning structure 12 is in the shape of a "-".

[0107] It can be understood that by setting the first positioning structure 12 on the bottom layer 10, it can help the bottom layer 10 and the detection layer 20 to be quickly positioned and assembled, improve production efficiency, and prevent installation misalignment.

[0108] The two shapes of “-” 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 be provided with 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 being recessed from the surface of the bottom layer 10 away from the detection layer 20 toward the inside of the first positioning structure 12.

[0110] In some other embodiments, the first positioning structure 12 may not be provided with the first cavity.

[0111] The bottom layer 10 may also include a first protruding structure 13. The first protruding structure 13 is protruded relative to the bottom layer 10 toward the surface of the detection layer 20 in the direction away from the battery cell 320. The first protruding structure 13 is close to the first positioning structure 12 and is spaced apart from the first positioning structure 12. The projection of the first protruding structure 13 along the thickness direction of the top patch 100 (Z direction shown in the figure) on the plane where the detection layer 20 is located is misaligned with the detection layer 20. That is, the projection of the detection layer 20 along the thickness direction of the top patch 100 on the bottom layer 10 is misaligned with the first protruding structure 13. That is, the first protruding structure 13 is located outside the outer edge of the detection layer 20. Specifically, the first protruding structure 13 can be spaced apart from the outer edge of the detection layer 20. The first protruding structure 13 can also abut against the outer edge of the detection layer 20. There is no restriction on this. As long as the first protruding structure 13 can position the detection layer 20, it is sufficient to prevent the bottom layer 10 and the detection layer 20 from being installed misaligned. The first protruding structure 13 and the bottom layer 10 may be connected to form an integrated structure.

[0112] The number of the first protruding structures 13 may be one or more. This embodiment does not limit the shape of the first protruding structures 13. When the number of the first protruding structures 13 is multiple, the shapes of the multiple first protruding structures 13 may be the same or different.

[0113] For a possible application scenario, see Figure 6 , the shape of the bottom layer 10 is rectangular. The number of the first protruding structures 13 can be two. The two first protruding structures 13 are arranged at intervals in the length direction of the bottom layer 10. The two first protruding structures 13 are also arranged at intervals in the width direction of the bottom layer 10. Each first protruding structure 13 is close to the corner of the bottom layer 10 and close to a first positioning structure 12. That is, the two first protruding structures 13 are respectively located at two diagonal corners in the bottom layer 10. One of the first protruding structures 13 is in the shape of a "「" character. The shape of the other first protruding structure 13 is in the shape of a "」" character. The first protruding structure 13 in the shape of a "「" character is close to the first positioning structure 12 in the shape of a "-" character. The first protruding structure 13 in the shape of a "」" character is close to the first positioning structure 12 in the shape of a "+" character. In addition, the projections of the two first protruding structures 13 along the thickness direction of the top patch 100 on the plane where the detection layer 20 is located are respectively located outside the two diagonal corners in the detection layer 20 to block the movement of the detection layer 20.

[0114] It is understandable that by providing the first protruding structure 13 on the bottom layer 10, it is not only possible to block the movement of the detection layer 20 and enhance the connection stability of the detection layer 20, but also to help the bottom layer 10 and the detection layer 20 to be quickly positioned and assembled, thereby improving production efficiency and preventing installation misalignment. At the same time, the combination of the first protruding 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 Figure 4 and Figure 6 , the bottom layer 10 may be provided with a first hole 14. The first hole 14 penetrates the bottom layer 10 along the thickness direction of the bottom layer 10. The first hole 14 is coaxially arranged and connected with the explosion-proof hole of the top cover 210, and is used to expose the explosion-proof valve. Among them, the maximum size of the first hole 14 in the length direction of the top patch 100 is D1. That is, the maximum size of the first hole 14 in the length direction of the bottom layer 10 is D1. The maximum size of the first hole 14 in the width direction of the top patch 100 is H1. That is, the maximum size of the first hole 14 in the width direction of the bottom layer 10 is H1.

[0116] The bottom layer 10 may also be provided with a fourth hole 15. The fourth hole 15 penetrates the bottom layer 10 along the thickness direction of the bottom layer 10. The fourth hole 15 and the first hole 14 are arranged at intervals in the length direction of the bottom layer 10. The fourth hole 15 is used for the pole to pass through. The maximum dimension of the fourth hole 15 in the length direction of the top patch 100 is Φ1. That is, the maximum dimension of the fourth hole 15 in the length direction 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] The number of the fourth holes 15 can be two. The two fourth holes 15 are arranged at intervals in the length direction of the bottom layer 10. One of the fourth holes 15 is for the positive electrode column to pass through. The other fourth hole 15 is for the negative electrode column 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 Figure 5a , Figure 5b and Figure 7 , Figure 7 yes Figure 4 A schematic structural diagram of the detection layer 20 of the top patch 100 is shown.

[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 arranged relative to each other in the thickness direction of the detection layer 20 (Z direction in the figure). 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 guide hole 11 of the bottom layer 10. The detection layer 20 can be composed of a pH (potential of hydrogen, PH) test paper or a material layer that can absorb an acid-base indicator, so that the detection layer 20 can change color when in contact with the electrolyte, so as to detect the leakage of the electrolyte 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 is protruded relative to the second surface 22 in a direction away from the battery cell 320. The protruding direction of the second positioning structure 23 relative to the detection layer 20 is the same as the protruding 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 relative to each other in the thickness direction of the top patch 100. The second positioning structure 23 is used to help the detection layer 20 to be positioned and assembled with the bottom layer 10 and the top layer 30, and plays a fool-proof role. The second positioning structure 23 and the detection layer 20 can be connected to form an integrated structure.

[0123] The number of the second positioning structures 23 may be one or more. This embodiment does not limit the shape of the second positioning structures 23. When the number of the second positioning structures 23 is multiple, the shapes of the multiple second positioning structures 23 may be similar, the same, or different. This embodiment does not limit the position of the second positioning structures 23 on the bottom layer 10, as long as the second positioning structures 23 correspond to the positions of the first positioning structures 12 of the bottom layer 10.

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

[0125] For a possible application scenario, see Figure 7 , the shape of the detection layer 20 is rectangular. The number of the second positioning structures 23 can be two. The two second positioning structures 23 are spaced apart in the length direction of the detection layer 20 (the X direction in the figure). The two second positioning structures 23 are also spaced apart in the width direction of the detection layer 20 (the Y direction in the figure). Each second positioning structure 23 is close to the corner of the detection layer 20. That is, the two second positioning structures 23 are respectively located at two diagonal corners in the detection layer 20. One of the second positioning structures 23 is in the shape of a "+". The other second positioning structure 23 is in the shape of a "-".

[0126] It is understandable that by setting the second positioning structure 23 on the detection layer 20, it can help the detection layer 20 to quickly locate and assemble with the bottom layer 10 and the top layer 30, improve production efficiency, and prevent installation misalignment. At the same time, setting the two second positioning structures 23 in two shapes, "+" and "-", 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 be provided with a second cavity. The opening of the second cavity is located at the first surface 21. The second cavity is formed by being recessed from the first surface 21 to the inside of the second positioning structure 23. The recessed direction of the second cavity relative to the second positioning structure 23 is the same as the recessed 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 achieve the connection between the detection layer 20 and the bottom layer 10.

[0128] Please refer to Figure 4 and Figure 7 , the detection layer 20 may be provided with a second hole 24. The second hole 24 penetrates the detection layer 20 along the thickness direction of the detection layer 20. The second hole 24 is coaxially arranged and connected 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. Wherein, the maximum size of the second hole 24 in the length direction of the top patch 100 is D2. That is, the maximum size of the second hole 24 in the length direction of the detection layer 20 is D2. The maximum size of the second hole 24 in the width direction of the top patch 100 is H2. That is, the maximum size of the second hole 24 in the width direction of the detection layer 20 is H2.

[0129] The detection layer 20 may also be provided with a fifth hole 25. The fifth holes 25 all penetrate the detection layer 20 along the thickness direction of the detection layer 20. The fifth hole 25 and the second hole 24 are spaced apart in the length direction of the detection layer 20. The fifth hole 25 is coaxially arranged and connected with the fourth hole 15 of the bottom layer 10, and is used for the pole to pass through. The maximum dimension of the fifth hole 25 in the length direction of the top patch 100 is Φ2. That is, the maximum dimension of the fifth hole 25 in the length direction 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 number of the fifth holes 25 can be two. The two fifth holes 25 are arranged at intervals in the length direction of the detection layer 20. One of the fifth holes 25 is for the positive electrode column to pass through. The other fifth hole 25 is for the negative electrode column to pass through. The second hole 24 is located between the two fifth holes 25.

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

[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 material or a 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 is protruded relative to the surface of the top layer 30 away from the detection layer 20 in the direction away from the battery cell 320. The protruding direction of the third positioning structure 31 relative to the top layer 30 is the same as the protruding direction of the first positioning structure 12 of the bottom layer 10 relative to the bottom layer 10, and is also the same as the protruding direction of the second positioning structure 23 of the detection layer 20 relative to the detection layer 20. The third positioning structure 31 is arranged relative to the second positioning structure 23 of the detection layer 20 and the first positioning structure 12 of the bottom layer 10 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 to play a fool-proof role. The third positioning structure 31 and the top layer 30 can be connected to form an integrated structure.

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

[0136] It can be understood that when there are multiple third positioning structures 31, the multiple third positioning structures 31 are set to symbols of different shapes, so that the third positioning structure 31 can be used as a marking symbol to help identify and assemble the top layer 30 and the detection layer 20, thereby preventing the top layer 30 and the detection layer 20 from being misaligned during installation.

[0137] For a possible application scenario, see Figure 6 , the top layer 30 is in a rectangular shape. The number of the third positioning structures 31 can be two. The two third positioning structures 31 are spaced apart in the length direction of the top layer 30 (the X direction in the figure). The two third positioning structures 31 are also spaced apart in the width direction of the top layer 30 (the Y direction in the figure). Each third positioning structure 31 is close to a corner of the top layer 30. That is, the two third positioning structures 31 are respectively located at two diagonally opposite corners of the top layer 30. One of the third positioning structures 31 is in the shape of a "+". The other third positioning structure 31 is in the shape of a "-".

[0138] It is understandable that by setting the third positioning structure 31 on the top layer 30, the top layer 30 and the detection layer 20 can be quickly positioned and assembled, the production efficiency can be improved, and the installation misalignment can be prevented. At the same time, the two third positioning structures 31 are set to be two shapes of "+" and "-", which 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 be provided with the third positioning structure 31 .

[0140] In this embodiment, the third positioning structure 31 may be provided with 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 being recessed from the surface of the top layer 30 away from the detection layer 20 to the inside of the third positioning structure 31. The recessed direction of the third cavity relative to the third positioning structure 31 is the same as the recessed direction of the second cavity of the detection layer 20 relative to the second positioning structure 23, and is also the same as the recessed 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, so as to achieve the connection between the top layer 30 and the detection layer 20.

[0141] To sum up, the protruding direction of the third positioning structure 31 of the top layer 30 relative to the top layer 30 is the same as the protruding 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 protruding direction of the first positioning structure 12 of the bottom layer 10 relative to the bottom layer 10.

[0142] In a possible application scenario, the first positioning structure 12 of the bottom layer 10 is protruded in a direction 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 is protruded in a direction away from the battery cell 320 relative to the second surface 22. The third positioning structure 31 of the top layer 30 is protruded in a direction 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 in the second cavity of the detection layer 20, so as to realize the positioning connection between the bottom layer 10 and the detection layer 20. The second positioning structure 23 of the detection layer 20 is located in the third cavity of the top layer 30, so as to realize the positioning connection between the detection layer 20 and the top layer 30.

[0143] In another possible application scenario, different from the previous application scenario, 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 in a direction close to the battery cell 320 relative to the first surface 21. The third positioning structure 31 of the top layer 30 protrudes in a direction close to 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 to achieve a positioning connection between the detection layer 20 and the bottom layer 10. The third positioning structure 31 of the top layer 30 is located in the second cavity of the detection layer 20 to achieve a positioning connection between the top layer 30 and the detection layer 20.

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

[0145] See also Figure 8 , the top layer 30 may also include a second protruding structure 32. The second protruding structure 32 is protruded relative to the surface of the top layer 30 toward the detection layer 20 in the direction close to the battery cell 320. The second protruding structure 32 is close to the third positioning structure 31 and is spaced apart from the third positioning structure 31. The projection of the second protruding structure 32 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100 is misaligned with the detection layer 20. That is, the projection of the detection layer 20 on the top layer 30 along the thickness direction of the top patch 100 is misaligned with the second protruding structure 32. That is, the second protruding structure 32 is located outside the outer edge of the detection layer 20. Specifically, the second protruding structure 32 can be spaced apart from the outer edge of the detection layer 20. The second protruding structure 32 can also abut against the outer edge of the detection layer 20. There is no restriction on this. As long as the second protruding structure 32 can position the detection layer 20, it is sufficient to prevent the top layer 30 from being misaligned with the detection layer 20. The second protruding structure 32 and the top layer 30 can be connected to form an integrated structure.

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

[0147] It is understandable that by providing the second protruding structure 32 on the top layer 30, not only can the detection layer 20 be blocked from moving and the connection stability of the detection layer 20 be enhanced, but also the top layer 30 and the detection layer 20 can be quickly positioned and assembled, production efficiency can be improved, and installation misalignment can be prevented. At the same time, the second protruding structure 32 and the third positioning structure 31 can be used in combination to provide double 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 protruding structure 32 on the bottom layer 10 along the thickness direction of the top patch 100 can be arranged offset from the first protruding structure 13. For example, the second protruding structure 32 can be located at the same diagonal of the top patch 100 as the first protruding structure 13. Alternatively, the second protruding structure 32 can be located at different diagonals of the top patch 100 than the first protruding structure 13.

[0149] For a possible application scenario, please refer to Figure 4 and Figure 8 , the top layer 30 is rectangular in shape. The number of the second protruding structures 32 can be two. The two second protruding structures 32 are spaced apart in the length direction of the top layer 30. The two second protruding structures 32 are also spaced apart in the width direction of the top layer. Each second protruding structure 32 is close to the corner of the top layer 30 and close to a third positioning structure 31. That is, the two second protruding structures 32 are respectively located at two diagonal corners in the top layer 30. One of the second protruding structures 32 is in the shape of a "「" character. The other second protruding structure 32 is in the shape of a "」" character. The second protruding structure 32 in the shape of a "「" character is close to the third positioning structure 31 in the shape of a "-" character. The second protruding structure 32 in the shape of a "」" character is close to the third positioning structure 31 in the shape of a "+" character. In addition, the projections of the two second protruding structures 32 along the thickness direction of the top patch 100 on the plane where the detection layer 20 is located are respectively located outside the two diagonal corners in the detection layer 20 to prevent the detection layer 20 from moving.

[0150] In this application scenario, the number of the first protruding structures 13 of the bottom layer 10 can be two. The two first protruding structures 13 are respectively located at two diagonal corners of the bottom layer 10. The shape of one of the first protruding structures 13 is a "「" shape. The shape of the other first protruding structure 13 is a "」" shape. The projections of the two first protruding structures 13 along the thickness direction of the top patch 100 on the plane where the detection layer 20 is located are staggered with the projections of the two second protruding structures 32 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100.

[0151] Specifically, the projections of the two first protruding structures 13 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100 are respectively located outside the two diagonal corners of the detection layer 20. The projections of the two second protruding structures 32 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100 are respectively located outside the other two diagonal corners of the detection layer 20. That is, the projections of the two first protruding structures 13 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100, and the projections of the two second protruding structures 32 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100, are respectively located outside the four corners of the detection layer 20.

[0152] Alternatively, the projections of the two first protruding structures 13 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100 are respectively located outside the two diagonal corners in the detection layer 20. The projections of the two second protruding structures 32 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100 are also respectively located outside or inside the two diagonal corners in the detection layer 20. And the projection of each second protruding structure 32 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100 is adjacent to the projection of a first protruding structure 13 located at the same corner on the plane where the detection layer 20 is located along the thickness direction of the top patch 100 and is staggered.

[0153] In another possible application scenario, different from the previous application scenario, the number of the second protruding structure 32 is one. The second protruding structure 32 is located at a corner of the top layer 30 and is close to a third positioning structure 31. The shape of the second protruding structure 32 is one of the shapes of "「" or "」". The projection of the second protruding structure 32 along the thickness direction of the top patch 100 on the plane where the detection layer 20 is located is located outside a corner in the detection layer 20.

[0154] In this application scenario, the number of the first protruding structure 13 is also one. The first protruding 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 protruding structure 32 is located. The shape of the first protruding structure 13 is the other of the "「" shape and the "」" shape. The projection of the first protruding structure 13 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100, and the projection of the second protruding structure 32 on the plane where the detection layer 20 is located along the thickness direction of the top patch 100, are respectively located on the outside of the two diagonally opposite corners in the detection layer 20.

[0155] Of course, in other application scenarios, the second protruding structure 32 may be provided on the top layer 30 , and the first protruding structure 13 may not be provided on the bottom layer 10 , and there is no strict limitation to this.

[0156] Please refer to Figure 4 and Figure 8 In this embodiment, the top layer 30 may be provided with a third hole 33. The third hole 33 penetrates the top layer 30 along the thickness direction of the top layer 30. 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 is connected to 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. Among them, the maximum size of the third hole 33 in the length direction of the top patch 100 is D3. That is, among them, the maximum size of the third hole 33 in the length direction of the top layer 30 is D3. The maximum size of the third hole 33 in the width direction of the top patch 100 is H3. That is, the maximum size of the third hole 33 in the width direction of the top patch 100 is H3.

[0157] In this embodiment, the maximum size D3 of the third hole 33 of the top layer 30 in the length direction of the top patch 100, the maximum size D1 of the first hole 14 of the bottom layer 10 in the length direction of the top patch 100, and the maximum size D2 of the second hole 24 of the detection layer 20 in the length direction of the top patch 100 satisfy the relationship:

[0158] D1=D3;

[0159] 10mm≥D2-D1≥2mm;

[0160] 10mm≥D2-D3≥2mm.

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

[0162] H1=H3;

[0163] 10mm≥H2-H1≥2mm;

[0164] 10mm≥H2-H3≥2mm.

[0165] It can be understood that, in the present embodiment, the bottom layer 10 and the top layer 30 are connected to each other by hot melting in the region where the detection layer 20 is extra. Therefore, by making the maximum size of the first hole 14 of the bottom layer 10 in the length and width direction of the top patch 100, and the maximum size of the third hole 33 of the top layer 30 in the length and width direction of the top patch 100, both smaller than the maximum size of the second hole 24 of the detection layer 20 in the length and width direction of the top patch 100. 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, so that the edge of the second hole 24 of the detection layer 20 does not participate in the welding during hot melting, thereby avoiding the problem of failure of the detection layer 20.

[0166] Please refer to Figure 4 and Figure 8 , the top layer 30 may also be provided with a sixth hole 34. The sixth holes 34 all penetrate the top layer 30 along the thickness direction of the top layer 30. The sixth hole 34 and the third hole 33 are spaced apart in the length direction 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 is connected 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 pole to pass through. The maximum size of the sixth hole 34 in the length direction of the top patch 100 is Φ3. That is, the maximum size of the sixth hole 34 in the length direction 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 the sixth holes 34 may be two. The two sixth holes 34 are spaced apart in the length direction of the top layer 30. One of the sixth holes 34 is for the positive electrode column to pass through. The other sixth hole 34 is for the negative electrode column to pass through. The third hole 33 is located between the two sixth holes 34.

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

[0170] Φ1=Φ3;

[0171] 8mm≥Φ2-Φ1≥2mm;

[0172] 8mm≥Φ2-Φ3≥2mm.

[0173] Alternatively, the maximum size of the sixth hole 34 of the top layer 30 in the width direction of the top patch 100 is Φ3, which satisfies the relationship between the maximum size Φ1 of the fourth hole 15 of the bottom layer 10 in the width direction of the top patch 100 and the maximum size 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] It can be understood that by making the maximum size of the fourth hole 15 of the bottom layer 10 in the length and width direction of the top patch 100, and the maximum size of the sixth hole 34 of the top layer 30 in the length and width direction of the top patch 100 smaller than the maximum size of the fifth hole 25 of the detection layer 20 in the length and width direction 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, so that the edge of the fifth hole 25 of the detection layer 20 does not participate in the welding during the hot melting, thereby avoiding the problem of failure of the detection layer 20.

[0178] It is understandable that during the manufacturing process of batteries, multiple components are connected by welding. However, waste gas (such as carbon dioxide and hydrogen) is easily generated during the welding process. The waste gas entering the weld will affect the strength of the weld, causing the gap at the weaker weld to become larger, and then causing the battery to leak gas / liquid. However, in the prior art, it is still impossible to detect the leakage of gas and liquid in the top cover assembly in a timely manner.

[0179] Therefore, in this embodiment, by making the detection layer 20 change color when in contact with the electrolyte, when the top cover assembly 200 leaks, the leaked electrolyte can penetrate into the detection layer 20 through the bottom layer 10, thereby causing the detection layer 20 to change color and be visually recognized by humans or machines, thereby avoiding continuous leakage. In addition, by observing the position where the color change occurs on the detection layer 20 through the top layer 30, the position where the leakage occurs in the top cover assembly 200 can also be located, such as leakage at the pole, leakage at the explosion-proof valve, etc.

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

[0181] It is understandable that directly setting the logo 50 on the top patch 100 instead of setting it on the top cover 210 can reduce the external leakage area of ​​the top cover 210, which is beneficial to reducing the leakage risk of the battery cell 320 and the shell 310.

[0182] Of course, in some other embodiments, the logo 50 may also be located on the second surface 22 of the detection layer 20, as long as the display of the logo 50 does not interfere with the color change of the detection layer 20. It is understandable that since the top layer 30 is transparent or translucent, when the logo 50 is located on the second surface 22 of the detection layer 20, the logo 50 can also be observed.

[0183] Please refer to 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 is connected between the bottom layer 10 and the top cover 210, and bonds the bottom layer 10 and the top cover 210 together. In order to ensure that the electrolyte can penetrate the bottom layer 10 and enter the detection layer 20, in this embodiment, there are the following two schemes to apply the adhesive on the bottom layer 10 to form the adhesive layer 40:

[0184] The first solution is to apply adhesive to the surface of the bottom layer 10 away from the detection layer 20 by using glue dispensing technology. When dispensing, the adhesive layer 40 formed by the adhesive should avoid the liquid guide hole 11 on the bottom layer 10. That is, the adhesive layer 40 falls into the projection of the bottom layer 10 along the thickness direction of the top patch 100 (Z direction in the figure), and is misaligned with the liquid guide hole 11 on the bottom layer 10. This can avoid the situation where the adhesive blocks the liquid guide hole 11, resulting in the electrolyte being unable to enter the detection layer 20 through the bottom layer 10.

[0185] The second solution is to make the material of the adhesive layer 40 a neutral material or an alkaline material. And the adhesive layer 40 can cover the liquid guide hole 11 of the bottom layer 10. Exemplarily, 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 permeated by the electrolyte, and the hydrolyzed product will not affect the detection result of the electrolyte by the detection layer 20. It should be noted that the composition of the adhesive of the present embodiment is not limited to this.

[0186] It is understandable that even if the liquid-conducting hole 11 on the bottom layer 10 is covered by the adhesive layer 40, as long as the amount of adhesive is not too much to block the liquid-conducting hole 11, the electrolyte can penetrate or dissolve the adhesive layer. Then, the electrolyte enters the detection layer 20 through the bottom layer 10, causing the detection layer 20 to change color, so that the leakage in the top cover assembly 200 can be detected. This greatly saves the processing time of setting the adhesive layer 40 on the bottom layer 10, thereby improving the production efficiency of the battery 300.

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

[0188] First step: placing the bottom layer 10 in the tooling.

[0189] Step 2: placing the detection layer 20 on the bottom layer 10 , and positioning and assembling the detection layer 20 and the bottom layer 10 by means of the first positioning structure 12 of the bottom layer 10 and the second positioning structure 23 of the detection layer 20 .

[0190] Step three: 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 bottom layer 10 and the area of ​​the top layer 30 where the detection layer 20 is extra by hot-melting to fix the detection layer 20 between the bottom layer 10 and the top layer 30 .

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

[0193] Second embodiment:

[0194] See also Fig. 9 , Fig. 9 It is another structural schematic diagram of the top patch 100 provided in the embodiment of the present application.

[0195] In this embodiment, the same contents as those in the first embodiment are not repeated here. The difference from the first embodiment is that the logo 50 is provided on the top cover 210, and a first through hole 60 is provided on the top patch 100 to expose the logo 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 there is a conflict.

[0196] The top patch 100 may be provided with 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 be connected to 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] It is understandable that by providing the first through hole 60 on the top patch 100 , the logo 50 on the top cover 210 can be exposed so as to confirm the code of the battery cell 320 during the manufacturing process of the battery 300 .

[0198] Please refer to Fig. 9 , Fig.10 and Fig.11 , Fig.10 yes Fig. 9 The schematic diagram of the structure of the bottom layer 10 of the top patch 100 is shown, Fig.11 yes Fig. 9 A schematic structural diagram of the detection layer 20 of the top patch 100 is shown.

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

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

[0201] The eighth hole 62 penetrates the detection layer 20 along the thickness direction of the detection layer 20. In the length direction of the detection layer 20, the eighth hole 62 can be connected to 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 logo 50 on the top cover 210. Among them, the maximum size of the eighth hole 62 in the length direction of the top patch 100 is d2. That is, the maximum size of the eighth hole 62 in the length direction of the detection layer 20 is d2. The maximum size of the eighth hole 62 in the width direction of the top patch 100 is h2. That is, the maximum size of the eighth hole 62 in the width direction of the detection layer 20 is h2.

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

[0203] It is understandable that by setting the first through hole 60 on the bottom layer 10 and the detection layer 20 of the top patch 100, the logo 50 on the top cover 210 can be exposed, so that the code of the battery cell 320 can be confirmed during the manufacturing process of the battery 300 through the transparent or translucent top layer 30. And because the top layer 30 seals the opening of one side of the first through hole 60, it can help reduce the external leakage area of ​​the top cover 210, which is conducive to reducing the leakage risk of the battery cell 320 and the housing 310.

[0204] In this embodiment, the maximum size of the seventh hole 61 in the length direction of the top patch 100 is d1 and the maximum size of the eighth hole 62 in the length direction of the top patch 100 is d2, which satisfies the relationship:

[0205] 6mm≥d2-d1≥1mm.

[0206] The maximum size of the seventh hole 61 in the width direction of the top patch 100 is h1 and the maximum size of the eighth hole 62 in the width direction of the top patch 100 is h2, which satisfies the relationship:

[0207] 6mm≥h2-h1≥1mm.

[0208] It can be understood that by making the maximum size of the eighth hole 62 on the detection layer 20 in the length and width direction of the top patch 100 larger than the maximum size of the seventh hole 61 on the bottom layer 10 in the length and width direction 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, so that the edge of the eighth hole 62 on the detection layer 20 does not participate in the welding during the hot melting, thereby avoiding the problem of failure of the detection layer 20. And the detection layer 20 is in a relatively sealed environment, not easily affected by the external environment, which is conducive to maintaining the stability of the detection function of the detection layer 20 for a long time.

[0209] The embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A top patch, characterized in that: The top patch comprises a bottom layer, a detection layer and a top layer which are stacked in sequence; The bottom layer is provided with a plurality of liquid guide holes, which are arranged at intervals on the bottom layer, and each of the liquid guide holes penetrates the bottom layer along the thickness direction of the bottom layer, and the bottom layer is used to be connected to the top cover; The detection layer includes a first surface and a second surface, the first surface and the second surface are arranged relative 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 the liquid guide holes, the second surface is connected to the top layer, the detection layer is used to change color when in contact with the electrolyte, and the top layer is used to observe the color change of the detection layer.

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 projection of the adhesive layer falling into the bottom layer along the thickness direction of the top patch is staggered with the plurality of liquid guide 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, and covers the plurality of liquid guide holes. 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 to 3, characterized in that: The material of the top layer is a transparent material or a semi-transparent material.

5. The top patch according to any one of claims 1 to 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 part of the first positioning structure is located in the second positioning structure, and at least part of the second positioning structure is located in the third positioning structure; or, At least part of the second positioning structure is located in the first positioning structure, and at least part of the third positioning structure is located in the second positioning structure.

6. The top patch according to any one of claims 1 to 3, characterized in that: The bottom layer is provided with a first protruding structure, the first protruding structure is protruding relative to the bottom layer toward the surface of the detection layer, and the projection of the detection layer on the bottom layer along the thickness direction of the top patch is staggered with the first protruding structure; and / or, The top layer is provided with a second protruding structure, which is protruding relative to the top layer toward the surface of 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 to 3, characterized in that: The outer edge of the bottom layer is also connected to the outer edge of the top layer so as 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 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 relationship: W1=W3; 10mm≥W1-W2≥2mm; 10mm≥W3-W2≥2mm.

10. The top patch according to claim 7, characterized in that: The bottom layer is provided with a first hole, the first hole penetrates the bottom layer along the thickness direction of the bottom layer, the detection layer is provided with a second hole, the second hole penetrates the detection layer along the thickness direction of the detection layer, the top layer is provided with a third hole, the third hole penetrates the top layer along the thickness direction of the top layer, 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; The maximum dimension D1 of the first hole in the length direction of the top patch, the maximum dimension D2 of the second hole in the length direction of the top patch, and the maximum dimension D3 of the third hole in the length direction of the top patch satisfy the relationship: D1=D3; 10mm≥D2-D1≥2mm; 10mm≥D2-D3≥2mm.

11. The top patch according to claim 10, characterized in that: The maximum dimension H1 of the first hole in the width direction of the top patch, the maximum dimension H2 of the second hole in the width direction of the top patch, and the maximum dimension H3 of the third hole in the width direction of the top patch satisfy the 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 is provided with a fourth hole, the fourth hole penetrates the bottom layer along the thickness direction of the bottom layer, the fourth hole and the first hole are spaced apart in the length direction of the bottom layer, the detection layer is provided with a fifth hole, the fifth hole penetrates the detection layer along the thickness direction of the detection layer, the fifth hole and the second hole are spaced apart in the length direction of the detection layer, the top layer is provided with a sixth hole, the sixth hole penetrates the top layer along the thickness direction of the top layer, the sixth hole and the third hole are spaced apart in 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 pole to pass through; The maximum dimension Φ1 of the fourth hole in the length direction of the top patch, the maximum dimension Φ2 of the fifth hole in the length direction of the top patch, and the maximum dimension Φ3 of the sixth hole in the length direction of the top patch satisfy the relationship: Φ1=Φ3; 8mm≥Φ2-Φ1≥2mm; 8mm≥Φ2-Φ3≥2mm.

13. The top patch according to any one of claims 1 to 3, characterized in that: The top patch also includes a mark, which is arranged on the surface of the top layer facing away from the detection layer.

14. The top patch according to any one of claims 1 to 3, characterized in that: The bottom layer is provided with a seventh hole, and the seventh hole penetrates the bottom layer along the thickness direction of the bottom layer. The detection layer is provided with an eighth hole, and the eighth hole penetrates the detection layer along the thickness direction of the detection layer. The seventh hole is coaxially arranged and connected with the eighth hole, and the seventh hole and the eighth hole are used to expose the logo of the top cover.

15. The top patch according to claim 14, characterized in that: 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 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 relationship: 6mm≥h2-h1≥1mm.

17. A top cover assembly, characterized in that: The top cover assembly comprises a top cover and a top patch as described in any one of claims 1 to 16, and the top cover is connected to the bottom layer.

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

19. An electrical equipment, characterized in that: The electric device comprises the battery as claimed in claim 18.

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