Battery top cover assembly, battery monomer, battery cell module and vehicle

Abstract

The utility model relates to the field of electric vehicles, and discloses a battery top cover assembly, a battery monomer, a battery cell module and a vehicle. The anti-explosion sheet is arranged on the cover plate; and the protection sheet is arranged on the cover plate and completely covers the outer surface of the anti-explosion sheet, and the denaturation temperature of the protection sheet exceeds 600 DEG C. The high-temperature substances sprayed from the explosion-proof hole of one battery top cover assembly adopting the protection sheet are accumulated on the protection sheet of the other adjacent battery top cover assembly, and the structure of the protection sheet cannot be damaged, so that a good protection effect can be achieved on the explosion-proof sheet below the protection sheet, and the consequence of thermal runaway spreading caused by ablation of the explosion-proof sheet is avoided.

Description

Technical Field

[0001] The present application belongs to the technical field of electric vehicles, and specifically relates to a battery top cover assembly, a battery cell, a battery cell module and a vehicle. Background Art

[0002] When a prismatic battery experiences thermal runaway, a runaway cell will eject high-temperature material from its explosion-proof flap on the top cover. This material can accumulate on the top covers of adjacent, functioning cells. Currently, a protective film shields the explosion-proof valve flap on the cell top cover. This film, however, has a thermal deformation temperature of less than 300°C. The cell explosion-proof valve flap is made of aluminum alloy, which has a thermal deformation temperature of less than 600°C. However, the temperature of the high-temperature material ejected from the cell is generally greater than 600°C. Therefore, in extreme cases, this can cause the explosion-proof valve flaps on adjacent cell top covers to erode, leading to the spread of thermal runaway. Utility Model Content

[0003] The purpose of the present application is to provide a battery top cover assembly, a battery cell, a battery module and a vehicle, which have the advantages of simple structure and can improve the safety of the battery cell, the battery module and the vehicle.

[0004] In order to achieve the above-mentioned objectives, the present application provides a battery top cover assembly in a first aspect, the battery top cover assembly comprising:

[0005] cover;

[0006] A bursting disk, arranged on the cover;

[0007] The protective sheet is arranged on the cover plate and completely covers the outer surface of the explosion-proof sheet. The denaturation temperature of the protective sheet exceeds 600°C.

[0008] In the embodiment of the present application, the denaturation temperature is the temperature at which the protective sheet undergoes thermal deformation, and the denaturation temperature ranges from 1000°C to 2000°C.

[0009] In the embodiment of the present application, the denaturation temperature is the temperature at which the protective sheet undergoes thermal decomposition, and the denaturation temperature ranges from 600°C to 2000°C.

[0010] In an embodiment of the present application, the protective sheet is made of ceramic composite tape, mica or quartz.

[0011] In an embodiment of the present application, a cavity is formed on the protection plate, which is recessed from the cover plate toward a side away from the explosion-proof plate.

[0012] In an embodiment of the present application, the thickness of the protective sheet ranges from 0.2 mm to 2 mm.

[0013] In an embodiment of the present application, the light transmittance of the protection sheet ranges from 70% to 99%.

[0014] In an embodiment of the present application, an adhesive layer for adhering the protection sheet and the cover plate together is provided on a side of the protection sheet close to the cover plate.

[0015] In the embodiment of the present application, the thickness of the adhesive layer is in the range of 0.03 mm to 0.5 mm.

[0016] In an embodiment of the present application, a liquid injection hole for adding electrolyte is further formed on the cover plate.

[0017] In an embodiment of the present application, the battery top cover assembly further includes an insulating member disposed on the cover plate.

[0018] In an embodiment of the present application, a battery cell eruption avoidance area is formed on the insulating member and is arranged opposite to the explosion-proof plate in the thickness direction of the explosion-proof plate, and a plurality of battery cell eruption avoidance holes are formed on the battery cell eruption avoidance area.

[0019] A second aspect of the present application provides a battery cell, which includes the above-mentioned battery top cover assembly.

[0020] A third aspect of the present application provides a battery cell module, which includes at least one battery cell column, and each battery cell column includes a plurality of the above-mentioned battery cells.

[0021] A fourth aspect of the present application provides a vehicle comprising the above-mentioned battery cell module.

[0022] It can be seen from the above technical solution that the battery top cover assembly includes a cover plate, an explosion-proof plate and a protective plate. The explosion-proof plate is arranged on the cover plate; the protective plate is arranged on the cover plate and completely covers the outer surface of the explosion-proof plate. The denaturation temperature of the protective plate exceeds 600°C. When the explosion-proof hole of a battery top cover assembly using the above-mentioned protective plate ejects high-temperature materials and accumulates on the protective plate of another adjacent battery top cover assembly, the protective plate will not suffer structural damage and can play a good protective role for the explosion-proof plate below it, thereby avoiding the consequences of thermal runaway and spread caused by the burning of the explosion-proof plate.

[0023] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without inventive work. In the drawings:

[0025] Figure 1 This is a first exploded schematic diagram of the battery top cover assembly in an embodiment of the present application (without insulating member);

[0026] Figure 2 This is a schematic diagram of the structure of the explosion-proof disk and the protection disk in the embodiment of the present application;

[0027] Figure 3 This is a schematic diagram of the structure of the protective sheet and the adhesive layer in the embodiment of the present application;

[0028] Figure 4 This is a partial cross-sectional schematic diagram of the protective sheet and the adhesive layer in the embodiment of the present application;

[0029] Figure 5 This is a schematic diagram of the structure of a battery cell in an embodiment of the present application (the battery top cover assembly is not installed);

[0030] Figure 6 This is a structural diagram of a battery cell in an embodiment of the present application (the battery top cover assembly is installed);

[0031] Figure 7 This is a second exploded schematic diagram of the battery top cover assembly in an embodiment of the present application (with an insulating member);

[0032] Figure 8 This is a third exploded schematic diagram of the battery top cover assembly in an embodiment of the present application (with a positive electrode riveted post and a negative electrode riveted post);

[0033] Figure 9 Schematic diagram of the structure of the insulating member in the embodiment of the present application.

[0034] Description of Reference Numerals

[0035] 1 Cover 2 Explosion-proof disk

[0036] 3 Protective sheet 301 cavity

[0037] 4 Adhesive layer 5 Explosion-proof hole

[0038] 6 Positive pole 7 Negative pole

[0039] 8 Shell 9 Liquid injection hole

[0040] 10 Insulation 1001 Battery core eruption avoidance area

[0041] 1002 Battery core eruption avoidance hole 1003 Positive electrode rivet column avoidance hole

[0042] 1004 Negative pole riveting column avoidance hole 11 Positive pole riveting column

[0043] 12 Negative electrode riveted column DETAILED DESCRIPTION

[0044] The following describes the specific embodiments of the present application in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application and are not intended to limit the present application.

[0045] In an embodiment of the present application, a battery top cover assembly is provided, such as Figure 1-Figure 2 As shown, the battery top cover assembly includes a cover plate 1, an explosion-proof plate 2 and a protective plate 3. The explosion-proof plate 2 is arranged on the cover plate 1 and is used to automatically open and release pressure under abnormal conditions such as overcharging, over-discharging, short circuit, etc. of the battery cell to prevent safety accidents such as overheating and explosion of the battery cell, thereby ensuring personal and property safety; the protective plate 3 is arranged on the cover plate 1 and completely covers the outer surface of the explosion-proof plate 2. The denaturation temperature of the protective plate 3 exceeds 600°C. If the material of the protective plate is a material that can undergo thermal deformation (such as quartz parts), the denaturation temperature is the temperature at which the protective plate 3 undergoes thermal deformation; if the material of the protective plate is a material that can undergo thermal decomposition (such as ceramic composite tape parts or mica parts), the denaturation temperature is the temperature at which the protective plate 3 undergoes thermal decomposition. Furthermore, the battery top cover assembly is suitable for battery cells (such as Figure 5-Figure 6 As shown, the battery cell also includes a housing 8, and the battery top cover assembly is mounted on the housing 8; a through-explosion hole 5 is formed on the cover plate 1, and an explosion-proof plate mounting cavity connected to the explosion-proof hole 5 is provided on the side of the cover plate 1 away from the protective plate 3. The explosion-proof plate 2 is embedded in the explosion-proof plate mounting cavity. This arrangement is conducive to streamlining the overall structure of the battery top cover assembly and facilitating the rapid and stable installation of the explosion-proof plate 2. The protective plate 3 is arranged on the top of the cover plate 1 and is opposite to the explosion-proof plate 2 from above; the battery top cover assembly also includes a positive electrode column 6 and a negative electrode column 7 arranged on the cover plate 1 and located on both sides of the protective plate 3. Since the degeneration temperature of the protective plate 3 in this embodiment exceeds 600°C, even if the explosion-proof hole of a battery top cover assembly using the above-mentioned protective plate 3 ejects high-temperature material and accumulates on the protective plate 3 of another adjacent battery top cover assembly, the protective plate 3 will not be damaged and can provide good protection for the explosion-proof plate 2 below it, avoiding the consequences of the explosion-proof plate 2 being burned and causing thermal runaway to spread.

[0046] In one embodiment of the present application, the denaturation temperature is the temperature at which the protective sheet 3 undergoes thermal deformation, and the denaturation temperature ranges from 1000°C to 2000°C.

[0047] Specifically, in this embodiment, the protective sheet 3 is made of a material that will deform when the temperature reaches the thermal deformation temperature (such as a quartz part), and the denaturation temperature of the protective sheet 3 is in the range of 1000°C-2000°C. For example, the denaturation temperature of the protective sheet 3 is 1000°C, 1050°C, 1100°C, 1200°C, 1300°C, 1500°C, 1700°C, 1900°C or 2000°C. Even if the battery cell is out of control, the explosion-proof hole of a battery top cover assembly using the above-mentioned protective sheet 3 will spray high-temperature materials and accumulate on the protective sheet 3 of another adjacent battery top cover assembly. The protective sheet 3 will not be thermally deformed, and can thus provide good protection for the explosion-proof sheet 2 below it, thereby avoiding the consequences of the explosion-proof sheet 2 being ablated and the spread of thermal runaway. For example, when the protection sheet 3 is made of a material that will deform when the temperature reaches the thermal deformation temperature, if the denaturation temperature of the protection sheet 3 is 1000°C, then when a high-temperature substance with a temperature not exceeding 1000°C is ejected from the explosion-proof hole of a battery top cover assembly and accumulates on the protection sheet 3 of another adjacent battery top cover assembly, the protection sheet 3 will not be thermally deformed; if the denaturation temperature of the protection sheet 3 is 1500°C, then when a high-temperature substance with a temperature not exceeding 1500°C is ejected from the explosion-proof hole of a battery top cover assembly and accumulates on the protection sheet 3 of another adjacent battery top cover assembly, the protection sheet 3 will not be thermally deformed; if the denaturation temperature of the protection sheet 3 is 2000°C, then when a high-temperature substance with a temperature not exceeding 2000°C is ejected from the explosion-proof hole of a battery top cover assembly and accumulates on the protection sheet 3 of another adjacent battery top cover assembly, the protection sheet 3 will not be thermally deformed.

[0048] In one embodiment of the present application, the denaturation temperature is the temperature at which the protective sheet 3 undergoes thermal decomposition, and the denaturation temperature ranges from 600°C to 2000°C.

[0049] Specifically, in this embodiment, the protective sheet 3 is made of a composite material (such as a ceramic composite tape or a mica component), and its denaturation temperature range is 600°C-2000°C. Optionally, the thermal weight loss rate of the protective sheet 3 in an environment with a temperature of at least 600°C (i.e., at the denaturation temperature) is less than 5% (here, 5% refers to 5% of the total mass of the protective sheet 3). For example, the thermal weight loss rate of the protective sheet 3 in an environment with a temperature of 600°C, 650°C, 800°C, 1000°C, 1200°C, 1400°C, 1600°C, 1800°C, etc. The thermal weight loss rate under an environment of 2000°C is 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, or 0.5%. Even if a battery cell loses control, if the explosion-proof hole of one battery top cover assembly using the above-mentioned protective sheet 3 ejects high-temperature material and deposits it on the protective sheet 3 of another adjacent battery top cover assembly, the protective sheet 3 will not rupture, decompose, or burn through. This effectively protects the explosion-proof sheet 2 below it, preventing the explosion-proof sheet 2 from being burned and causing the spread of thermal runaway. Furthermore, the preset thermal weight loss rate in this embodiment is preferably within the range of 0-1%, which helps to further ensure the protective performance of the protective sheet 3 of the composite material component. For example, when the protective sheet 3 is made of a composite material, if the denaturation temperature of the protective sheet 3 is 600°C, and the thermal weight loss rate of the protective sheet 3 in an environment with a temperature of 600°C is 0.01%, then when a high-temperature substance with a temperature not exceeding 600°C is ejected from the explosion-proof hole of a battery top cover assembly and accumulates on the protective sheet 3 of another adjacent battery top cover assembly, the ratio of all the mass lost by the protective sheet 3 during the heating process to the original mass does not exceed 0.01%. At this time, the protective sheet 3 will not rupture, decompose or burn through, and can provide good protection for the explosion-proof sheet 2 below it; if the denaturation temperature of the protective sheet 3 is 1600°C, and the thermal weight loss rate of the protective sheet 3 in an environment with a temperature of 1600°C is 0.2%, then the explosion-proof hole of a battery top cover assembly When a high-temperature substance with a temperature not exceeding 1600°C is ejected from an explosion-proof hole of a battery top cover assembly and accumulates on the protection sheet 3 of another adjacent battery top cover assembly, the ratio of all the mass lost by the protection sheet 3 during the heating process to the original mass does not exceed 0.2%, and the protection sheet 3 will not rupture, decompose or burn through. At this time, the protection sheet 3 will not rupture, decompose or burn through, and can provide good protection for the explosion-proof sheet 2 below it.

[0050] In one embodiment of the present application, the protective sheet 3 is a ceramic composite tape. Specifically, the ceramic composite tape is mainly made of ceramicized fire-resistant silicone rubber and high-temperature resistant glass fiber cloth as the base material, which is coated and pressed. It has excellent electrical insulation, flame jet resistance and heat insulation capabilities. It can withstand the impact of flames above 1000°C (such as 1300°C) for a long time (such as 30 minutes) without penetration. After high-temperature sintering, it quickly ceramicizes. After the battery module loses control, the protective sheet 3 made of ceramic composite tape can still play a good insulating and protective role, thereby improving the safety of battery cells, battery modules and vehicles. In addition, the ceramic composite tape also has excellent aging resistance and corrosion resistance, and is an ideal material for flame blocking, flame retardant protection, and insulation protection.

[0051] In one embodiment of the present application, the protective sheet 3 is a mica component. Specifically, the mica component is composed of polysilicon muscovite, quartz, garnet and rutile, etc., and has the characteristics of being pollution-free, insulating, voltage-resistant, heat-insulating and flame-retardant. It can effectively reduce the risk of battery thermal runaway. Even if battery thermal runaway occurs in extreme cases, the protective sheet 3 made of mica can effectively prevent the fire from spreading inside the battery cell module.

[0052] In one embodiment of the present application, the protective sheet 3 is made of quartz. Specifically, quartz has the characteristics of high chemical stability, oxidation resistance, corrosion resistance, stable physical properties, good transparency, etc., and can withstand high temperatures above 1000°C. Even if the battery cell is out of control, the explosion-proof sheet of a battery cell will spray high-temperature materials and accumulate on the protective sheet 3 made of quartz of another adjacent battery top cover assembly. The protective sheet 3 will not melt or deform, and can play a good protective role.

[0053] In one embodiment of the present application, Figure 2 and Figure 4 As shown, a cavity 301 is formed on the protection plate 3 and is recessed from the cover plate 1 toward a side away from the explosion-proof plate 2 .

[0054] Specifically, in the present embodiment, the opening method of the explosion-proof disc 2 can be selected as a hinge-type opening (in the present embodiment, the explosion-proof disc 2 includes an opening portion and a connecting portion (not shown in the figure) surrounding the opening portion, and a plurality of notches are provided on the opening portion, which divide the opening portion into a plurality of opening pieces. When the explosion-proof disc 2 is not opened, the plurality of opening pieces are in a closed state; when the pressure inside the explosion-proof disc 2 reaches the opening pressure, the notches are broken, and each opening piece is deflected relative to the connecting portion to open the explosion-proof disc 2. The above-mentioned opening method of the explosion-proof disc 2 is a hinge-type opening), and a concave cavity 301 is formed on the protective sheet 3, which is recessed toward the side away from the explosion-proof disc 2, so as to avoid the opening of the explosion-proof disc 2 in the above-mentioned opening method being subject to greater restrictions, and is more conducive to the smooth opening and pressure relief of the explosion-proof disc 2. Furthermore, in this embodiment, the first distance d1 between the bottom wall of the cavity 301 and the bursting disc 2 is ≥ 5 mm. For example, if d1 is 5 mm, 6 mm, 8 mm, 10 mm, or 12 mm, this further reduces the opening restriction of the bursting disc 2 and enhances the safety protection provided by the bursting disc 2. For example, if the first distance d1 between the bottom wall of the cavity 301 and the bursting disc 2 is 5 mm, this distance can avoid any restrictions on the opening of the bursting disc 2, allowing the bursting disc 2 to open smoothly and release pressure. If the first distance d1 between the bottom wall of the cavity 301 and the bursting disc 2 is 10 mm, this distance further reduces the opening restriction of the bursting disc 2, further facilitating smooth opening and pressure relief of the bursting disc 2.

[0055] Furthermore, in this embodiment, the second spacing d2 between the side of the cover plate 1 close to the protective plate 3 and the explosion-proof plate 2 can be selected in the range of 1.5mm-2mm, such as d2 is 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm or 2mm. The above-mentioned value of d2 can not only avoid the excessive height difference between the explosion-proof plate 2 and the cover plate 1, and thus avoid the situation where the height of the battery cell is increased but the internal space is not fully utilized, which is not conducive to the miniaturization design of the battery cell, but also avoid the situation where it is easy to be accidentally touched by external personnel or equipment during the production process due to the small height difference between the explosion-proof plate 2 and the cover plate 1. For example, if the second distance d2 between the side of the cover plate 1 close to the protective sheet 3 and the explosion-proof sheet 2 is 1.5mm, it can avoid the height difference between the explosion-proof sheet 2 and the cover plate 1 being too large, thereby avoiding the situation where the height of the battery cell is increased but the internal space is not fully utilized, which is conducive to the miniaturization design of the battery cell; if the second distance d2 between the side of the cover plate 1 close to the protective sheet 3 and the explosion-proof sheet 2 is 1.7mm, while making full use of the internal space of the battery cell, it avoids the situation where the explosion-proof sheet 2 is easily touched by external personnel or equipment during the production process; if the second distance d2 between the side of the cover plate 1 close to the protective sheet 3 and the explosion-proof sheet 2 is 2mm, it can fully avoid the situation where the explosion-proof sheet 2 is easily touched by external personnel or equipment during the production process due to the small height difference between the explosion-proof sheet 2 and the cover plate 1.

[0056] Furthermore, in this embodiment, the depth d0 of the cavity 301 is ≥ 3.5 mm. Depths of the cavity 301 within the aforementioned range of values can ensure the pressure relief effect upon opening of the bursting disk 2, such as d0 of 3.5 mm, 3.6 mm, 3.8 mm, 4 mm, or 4.2 mm. For example, if the depth d0 of the cavity 301 is 3.5 mm, this depth of the cavity 301 can ensure the pressure relief effect upon opening of the bursting disk 2; if the depth d0 of the cavity 301 is 4.2 mm, this depth of the cavity 301 further enhances the pressure relief effect upon opening of the bursting disk 2.

[0057] In one embodiment of the present application, the thickness of the protective sheet 3 ranges from 0.2 mm to 2 mm. If the thickness of the protective sheet 3 is less than 0.2 mm, it is difficult to protect the explosion-proof disc 2 of the battery. If the thickness of the protective sheet 3 is greater than 2 mm, the weight of the protective sheet 3 and the space occupied by the protective sheet 3 are increased, which in turn easily leads to an increase in the overall weight, thickness (or height) of the battery top cover assembly, which is not conducive to the miniaturization design of the battery cell and battery module. In addition, it will also cause waste of manufacturing materials. For example, if the thickness of the protective sheet 3 is 0.2 mm, it can avoid increasing the weight and space occupied by the protective sheet 3, avoid increasing the overall weight and thickness (or height) of the battery top cover assembly, and facilitate the miniaturization design of the battery cell and battery module. If the thickness of the protective sheet 3 is 1 mm, it can avoid increasing the weight and space occupied by the protective sheet 3, avoid increasing the overall weight and thickness (or height) of the battery top cover assembly, and ensure that the explosion-proof disc 2 of the battery is protected. If the thickness of the protective sheet 3 is 2 mm, it can fully ensure that the explosion-proof disc 2 of the battery is protected.

[0058] Furthermore, in this embodiment, the thickness range of the protective sheet 3 is preferably 0.3mm-0.5mm, such as the thickness of the protective sheet 3 is 0.35mm, 0.4mm, 0.45mm or 0.5mm. The protective sheet 3 of the above thickness can further avoid being burned through by the high-temperature battery cell ejecta due to being too thin, and can also avoid wasting manufacturing materials due to being too thick. In addition, the protective sheet 3 of the above thickness also has the advantage of being easy to fold and bend, so that when a certain battery cell ejects, the protective sheet 3 corresponding to the top of this battery cell will be blown away, which can avoid the situation where the protective sheet 3 lies across the exhaust channel of the battery cell and affects the drainage of the battery cell ejecta, thereby avoiding the accumulation of ejecta and increasing the risk of burning adjacent battery cells. For example, if the thickness of the protective sheet 3 is 0.3 mm, the protective sheet 3 is easy to fold and bend, so that when a certain battery cell erupts, the protective sheet 3 corresponding to the top of the battery cell is easy to be blown away, which can avoid the protective sheet 3 lying across the exhaust channel of the battery cell and affecting the drainage of the battery cell spray valve material; if the thickness of the protective sheet 3 is 0.4 mm, it can further avoid being burned through by the high-temperature battery cell spray due to being too thin, and can also avoid wasting manufacturing materials due to being too thick, and it is easy to fold and bend, so that when a certain battery cell erupts, the protective sheet 3 corresponding to the top of the battery cell is easy to be blown away, which can avoid the protective sheet 3 lying across the exhaust channel of the battery cell and affecting the drainage of the battery cell spray valve material; if the thickness of the protective sheet 3 is 0.5 mm, it can fully ensure that the protective sheet 3 is prevented from being burned through by the high-temperature battery cell spray due to being too thin.

[0059] In one embodiment of the present application, the light transmittance of the protective sheet 3 is in the range of 70%-99%, such as 75%, 80%, 85%, 90%, or 99%. The protective sheet 3 in this embodiment can be made of a high-temperature resistant transparent material, such as quartz glass. The protective sheet 3 in the above light transmittance range allows workers to easily and conveniently observe the interior of the explosion-proof hole 5, such as whether the explosion-proof disk 2 has been touched or damaged, without opening or uncovering the protective sheet 3. For example, if the light transmittance of the protective sheet 3 is in the range of 70%, workers can observe the interior of the explosion-proof hole 5 without opening or uncovering the protective sheet 3; if the light transmittance of the protective sheet 3 is in the range of 80%, workers can observe the interior of the explosion-proof hole 5 relatively easily and conveniently without opening or uncovering the protective sheet 3; and if the light transmittance of the protective sheet 3 is in the range of 99%, workers can observe the interior of the explosion-proof hole 5 effortlessly without opening or uncovering the protective sheet 3.

[0060] In one embodiment of the present application, Figure 3As shown, an adhesive layer 4 for adhering the protective sheet 3 and the cover plate 1 together is provided on one side of the protective sheet 3 close to the cover plate 1, thereby improving the convenience of installing the protective sheet 3. The adhesive layer 4 in this embodiment can be optionally a double-sided tape to effectively ensure the stability of the adhesion between the protective sheet 3 and the cover plate 1.

[0061] In one embodiment of the present application, the thickness of the adhesive layer 4 ranges from 0.03 mm to 0.5 mm, such as the thickness of the adhesive layer 4 can be 0.03 mm, 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm or 0.5 mm. The adhesive layer 4 of the above thickness can ensure that the protective sheet 3 and the cover plate 1 are firmly bonded together, and can also prevent the overall thickness (or height) of the battery top cover assembly from being too large. For example, if the thickness of the adhesive layer 4 is 0.03 mm, the overall thickness (or height) of the battery top cover assembly can be prevented from being too large; if the thickness of the adhesive layer 4 is 0.3 mm, it can ensure that the protective sheet 3 and the cover plate 1 are firmly bonded together, and can also prevent the overall thickness (or height) of the battery top cover assembly from being too large; if the thickness of the adhesive layer 4 is 0.5 mm, it can fully ensure that the protective sheet 3 and the cover plate 1 are firmly bonded together.

[0062] Furthermore, in this embodiment, the protective sheet 3 covers the top of the explosion-proof hole 5, and the coverage area of the protective sheet 3 is larger than the coverage area of the explosion-proof hole 5. The adhesive layer 4 is arranged at the bottom of the protective sheet 3 and is annular. This arrangement can not only ensure the adhesion between the protective sheet 3 and the cover plate 1 but also save materials for making the adhesive layer 4. It can also reduce the possibility of the adhesive layer 4 sticking to other objects during the installation of the protective sheet 3, which is conducive to further improving the convenience of installing the protective sheet 3.

[0063] Furthermore, if Figure 7 As shown, in this embodiment, the cover plate 1 is further formed with a liquid injection hole 9 located between the explosion-proof disk installation cavity and the positive electrode column 6 , and the liquid injection hole 9 is used to inject electrolyte into the interior of the housing 8 .

[0064] Furthermore, in this embodiment, the battery top cover assembly also includes an insulating member 10 disposed below the cover plate 1. This insulating member 10 is used to insulate and protect the interior of the battery cell. In this embodiment, the insulating member 10 is made of plastic. In other embodiments, the insulating member may also be made of other materials, such as polypropylene, polyethylene terephthalate, or polyimide.

[0065] In one embodiment of the present application, a cell eruption avoidance area 1001 is formed on the insulating member 10 and is arranged opposite to the explosion-proof plate 2 in the thickness direction of the explosion-proof plate 2. A plurality of cell eruption avoidance holes 1002 are formed on the cell eruption avoidance area 1001. The plurality of cell eruption avoidance holes 1002 form a grid staggered in horizontal and vertical directions. The area range of the cell eruption avoidance holes 1002 is 25mm. 2 -70mm2 , so that when the battery cell loses control, the high-temperature ejecta can be ejected smoothly. For example, if the area of the battery cell ejection avoidance hole 1002 is 25mm 2 , it ensures that when the battery cell loses control, the high-temperature ejecta can be ejected outward through the battery cell ejection avoidance hole 1002; if the area range of the battery cell ejection avoidance hole 1002 is 55mm 2 , it improves the smoothness of the outward eruption of high-temperature ejecta when the battery cell is out of control; if the area range of the battery cell eruption avoidance hole 1002 is 70mm 2 , then when the battery cell loses control, the high-temperature ejecta can be ejected smoothly.

[0066] Furthermore, the cross-sectional area of the ribs forming the battery core eruption avoidance hole 1002 is in the range of 0.5 mm 2 -2mm 2 The smaller size of the ribs within the above cross-sectional area range results in a lower structural strength of the grid formed by the multiple cell ejection avoidance holes 1002, which ensures that the ejected material from the cell will destroy the rib structure under high temperature, thereby forming a large hole that runs through the top and bottom, further improving the smoothness of the ejected material from the cell and avoiding the blockage of the ejected material from the cell. For example, if the cross-sectional area of the ribs forming the cell ejection avoidance holes 1002 is 0.5mm 2 , which makes the structural strength of the grid composed of multiple battery cell ejection avoidance holes 1002 low, and the rib structure is easily damaged, which fully ensures the smoothness of the ejection of the battery cell ejection and avoids the situation of battery cell ejection blockage; if the cross-sectional area of the ribs surrounding the battery cell ejection avoidance holes 1002 is 1.2mm 2 , the rib structure is easier to be destroyed, and a large hole can be formed that runs through the top and bottom, so that the battery ejection material can be ejected smoothly; if the cross-sectional area of the rib surrounding the battery ejection avoidance hole 1002 is 1.5mm 2 , the rib structure can be destroyed, and a large hole can be formed that runs through the top and bottom to avoid clogging of the battery cell by ejected materials.

[0067] In one embodiment of the present application, a positive electrode rivet column avoidance hole 1003 and a negative electrode rivet column avoidance hole 1004 are formed on the insulating part 10, which are respectively located on both sides of the battery cell eruption avoidance area 1001, and the battery top cover assembly also includes a positive electrode rivet column 11 and a negative electrode rivet column 12, wherein the positive electrode rivet column 11 passes through the positive electrode rivet column avoidance hole 1003 from bottom to top and is riveted to the positive electrode column 6, and the negative electrode rivet column 12 passes through the negative electrode rivet column avoidance hole 1004 from bottom to top and is riveted to the negative electrode column 7, thereby ensuring the tightness and reliability of the connection between the cover plate 1 and the insulating part 10.

[0068] Another embodiment of the present application provides a battery cell, such as Figure 5-Figure 6As shown, the battery cell includes the battery top cover assembly in the above embodiment. By making the denaturation temperature of the protective sheet exceed 600°C, the protective sheet 3 can be prevented from accumulating high-temperature substances erupted from the explosion-proof sheet 2 without structural damage, thereby providing good protection for the explosion-proof sheet 2 below, avoiding the consequences of thermal runaway caused by the ablation of the explosion-proof sheet 2, and improving the safety of the battery cell, battery cell module and vehicle.

[0069] In another embodiment of the present application, a battery cell module is provided, which includes at least one battery cell column, each battery cell column including multiple battery cells according to the above embodiments. By making the denaturation temperature of the protective sheet exceed 600°C, the protective sheet 3 can be prevented from being structurally damaged by the accumulation of high-temperature substances erupted from the explosion-proof sheet 2, thereby providing good protection for the explosion-proof sheet 2 below it, avoiding the consequences of thermal runaway caused by the burning of the explosion-proof sheet 2, and improving the safety of the battery cells, battery cell modules and vehicles.

[0070] In another embodiment of the present application, a vehicle is provided, which includes the battery cell module of the above embodiment. By making the denaturation temperature of the protective sheet exceed 600°C, the protective sheet 3 can be prevented from accumulating high-temperature substances erupted from the explosion-proof sheet 2 and will not suffer structural damage, thereby providing good protection for the explosion-proof sheet 2 below it, avoiding the consequences of thermal runaway caused by the burning of the explosion-proof sheet 2, and improving the safety of battery cells, battery cell modules and vehicles.

[0071] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0072] In this application, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0073] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0074] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A battery top cover assembly, characterized in that: The battery top cover assembly includes: cover; An explosion-proof disk is arranged on the cover plate; A protection sheet is provided on the cover plate and completely covers the outer surface of the explosion-proof sheet, and the denaturation temperature of the protection sheet exceeds 600°C.

2. The battery top cover assembly according to claim 1, characterized in that: The denaturation temperature is the temperature at which the protective sheet undergoes thermal deformation, and the range of the denaturation temperature is 1000° C.-2000° C.

3. The battery top cover assembly according to claim 1, characterized in that: The denaturation temperature is the temperature at which the protective sheet undergoes thermal decomposition, and the range of the denaturation temperature is 600°C-2000°C.

4. The battery top cover assembly according to claim 1, characterized in that: The protective sheet is made of ceramic composite tape, mica or quartz.

5. The battery top cover assembly according to claim 1, characterized in that: The protection plate is formed with a cavity that is recessed from the cover plate toward a side away from the explosion-proof plate.

6. The battery top cover assembly according to claim 1, characterized in that: The thickness of the protective sheet ranges from 0.2 mm to 2 mm.

7. The battery top cover assembly according to claim 1, characterized in that: The light transmittance of the protective sheet ranges from 70% to 99%.

8. The battery top cover assembly according to claim 1, characterized in that: An adhesive layer for adhering the protection sheet and the cover plate together is provided on a side of the protection sheet close to the cover plate.

9. The battery top cover assembly according to claim 8, characterized in that: The thickness of the adhesive layer is in the range of 0.03 mm to 0.5 mm.

10. The battery top cover assembly according to any one of claims 1 to 9, characterized in that: The cover plate is also provided with a liquid injection hole for injecting electrolyte.

11. The battery top cover assembly according to any one of claims 1 to 9, characterized in that: The battery top cover assembly further includes an insulating member disposed below the cover plate.

12. The battery top cover assembly according to claim 11, characterized in that: The insulating member is provided with a battery cell eruption avoidance area which is arranged opposite to the explosion-proof plate in the thickness direction of the explosion-proof plate, and the battery cell eruption avoidance area is provided with a plurality of battery cell eruption avoidance holes.

13. A battery cell, characterized in that: The battery cell includes the battery top cover assembly according to any one of claims 1 to 12.

14. A battery cell module, characterized in that: The battery cell module includes at least one battery cell column, and each of the battery cell columns includes a plurality of battery cells as claimed in claim 13 .

15. A vehicle, characterized in that: The vehicle includes the battery cell module according to claim 14.

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