Battery cover and battery

Abstract

Provided in the present application are a battery cover (100) and a battery (200). The battery cover (100) comprises: a main body (101), wherein a pressure relief hole (102) penetrating in a thickness direction of the main body (101) is formed therein; an explosion-proof sheet (140), wherein the explosion-proof sheet (140) is connected to the main body (101), and the explosion-proof sheet (140) covers the pressure relief hole (102) and has a weak portion (130) for explosion initiation; and a temperature sensing member (120), which is attached to the explosion-proof sheet (140) and at least partially cover the weak portion (130), wherein the temperature sensing member (120) is configured such that when the temperature is greater than a predetermined value, a critical fracture pressure decreases as the temperature increases. By means of the present application, an opening force of an explosion-proof valve can be increased when a battery (200) works normally, which is beneficial to preventing the risk of a battery cover (100) being erroneously opened due to an increase in an internal pressure caused by the pressure inside the battery (200) being affected by external factors; meanwhile, the battery cover (100) can be opened in advance using a small opening force when the battery (200) is out of control, thereby helping to take away the heat of the out-of-control battery (200) earlier, alleviating or even blocking the problem of same being continuously out of control due to heat transfer from the out-of-control battery (200) to an adjacent battery (200), and ensuring the safety of the battery (200) to the greatest possible extent.

Description

Battery cover and battery

[0001] This application claims priority to Chinese Patent Application No. 202411059834.X, filed on August 2, 2024, entitled "Battery Cover and Battery", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, and more particularly to a battery cover and a battery. Background Technology

[0003] In daily use, power batteries such as lithium-ion batteries may experience thermal runaway due to improper use. The internal temperature of the battery will continue to rise, and the battery may explode.

[0004] To prevent battery explosions, relevant technologies typically include an explosion-proof valve on the battery. When the internal pressure of the battery increases to a certain value, the explosion-proof valve bulges outward under pressure, causing the weld between the explosion-proof valve and the aluminum shell to crack and break. The explosion-proof valve then opens, carrying away the heat inside the battery to gradually slow down the temperature rise and protect the battery's safety.

[0005] However, in related technologies, the opening force of the explosion-proof valve is a fixed value, which cannot adequately meet the safety requirements of the battery under different operating conditions. Furthermore, the mechanical strength of the explosion-proof valve in related technologies is not affected by temperature. Summary of the Invention

[0006] In view of the above problems, this application provides a battery cover and a battery that can increase the opening force of the explosion-proof valve when the battery is working normally, thereby helping to avoid the risk of the explosion-proof valve opening accidentally due to the increase of internal pressure caused by external factors affecting the internal pressure of the battery; at the same time, it can open the explosion-proof valve in advance with a small opening force when the battery is out of control, thereby helping to remove the heat of the out-of-control battery earlier, mitigating or even blocking the problem of the out-of-control battery continuing to run out of control by heat transfer to adjacent batteries, and ensuring the safety of the battery to the greatest extent.

[0007] To achieve the above objectives, this application provides the following technical solution:

[0008] A first aspect of this application provides a battery cover, including a main body having a pressure relief hole extending through its thickness direction; an explosion-proof sheet connected to the main body, the explosion-proof sheet covering the pressure relief hole and having a weak portion for detonation; and a temperature sensor attached to the explosion-proof sheet and at least partially covering the weak portion, the temperature sensor being adapted to reduce the critical rupture pressure as the temperature increases when the temperature is greater than a predetermined value.

[0009] In one feasible implementation, a heat-conducting element is provided on the main body, and the heat-conducting element is connected to the temperature sensing element.

[0010] In one feasible implementation, the temperature sensing element and the heat-conducting element are integrally formed by conventional injection molding or nano-injection molding; or, the temperature sensing element and the heat-conducting element are bonded together.

[0011] In one possible implementation, the main body includes a first surface, which is the side of the main body closest to the battery cell; the temperature sensing element includes a first temperature sensing element, the heat conducting element includes a first heat conducting element, the first temperature sensing element is attached to the weak portion located on the first surface and connected to the first heat conducting element, and the first temperature sensing element and the first heat conducting element are offset on the first surface.

[0012] In one possible implementation, the main body includes a second surface, which is the side of the main body opposite to the battery cell; the temperature sensing element includes a second temperature sensing element, the heat conducting element includes a second heat conducting element, the second temperature sensing element is attached to the weak portion located on the second surface and connected to the second heat conducting element, and the second temperature sensing element and the second heat conducting element are offset on the second surface.

[0013] In one possible implementation, the weak point is a groove formed in the explosion-proof sheet.

[0014] In one feasible implementation, the weak portion is an annular structure, the first temperature sensing element is an annular structure, and the first temperature sensing element surrounds the outer periphery of the first heat-conducting element; and / or, the second temperature sensing element is an annular structure, and the second temperature sensing element surrounds the outer periphery of the second heat-conducting element.

[0015] In one possible implementation, the first temperature sensor is a sheet-like structure that covers the weak portion; and / or, the second temperature sensor is a sheet-like structure that covers the weak portion.

[0016] In one feasible implementation, one of the first temperature sensing element and the second temperature sensing element is an annular structure, correspondingly surrounding the outer periphery of one of the first heat-conducting elements and the second heat-conducting element; the other of the first temperature sensing element and the second temperature sensing element is a sheet-like structure, and covers the corresponding weak portion.

[0017] In one feasible implementation, the temperature sensing element is located on the side close to the battery cell, and the temperature sensing element includes any one of PP, PPS, or PE.

[0018] And / or, the temperature sensing element is located on the side facing away from the battery cell, and the temperature sensing element includes any one of PP, PPS, PE or plastic.

[0019] In one feasible implementation, the thickness of the temperature sensor is greater than the height of the weak portion, and the surface of the temperature sensor protrudes beyond the surface of the weak portion.

[0020] A second aspect of this application provides a battery, including a battery cell, a battery casing, and a battery cover. The battery cover covers the battery casing and forms a cavity, and the battery cell is located in the cavity.

[0021] This application provides a battery cover and a battery. When the battery is operating normally, the ambient temperature of the explosion-proof valve is lower than a preset temperature. The temperature sensor is less affected by the ambient temperature, and its critical value (mechanical strength) remains almost unchanged. This helps increase the opening force of the explosion-proof valve itself, thus avoiding the risk of the explosion-proof valve opening accidentally due to increased internal pressure caused by external factors, ensuring the normal operation of the battery. When the ambient temperature of the battery is higher than the preset temperature, the battery is in a runaway state. When the temperature exceeds the preset value, the critical pressure for rupture of the temperature sensor decreases with increasing temperature. This allows the explosion-proof valve to open earlier with a smaller opening force when the battery is runaway, helping to dissipate the heat of the runaway battery sooner and mitigating or even blocking the problem of the runaway battery continuing to runaway due to heat transfer to adjacent batteries, thus maximizing battery safety. Attached Figure Description

[0022] Figure 1 is a schematic diagram of the battery structure provided in an embodiment of this application;

[0023] Figure 2 is a top view of the battery provided in an embodiment of this application;

[0024] Figure 3 is a schematic diagram of the structure of the battery cover provided in an embodiment of this application;

[0025] Figure 4 is a top view of the battery cover provided in an embodiment of this application;

[0026] Figure 5 is a cross-sectional view of the battery cover provided in an embodiment of this application;

[0027] Figure 6a is a schematic diagram of the explosion-proof sheet and temperature sensor of the first structure provided in the embodiment of this application;

[0028] Figure 6b is an exploded view of the explosion-proof sheet and temperature sensing element of the first structure provided in the embodiment of this application;

[0029] Figure 6c is a cross-sectional view of the explosion-proof sheet and temperature sensing element of the first structure provided in the embodiment of this application;

[0030] Figure 7a is a schematic diagram of the explosion-proof sheet and temperature sensor of the second structure provided in the embodiment of this application;

[0031] Figure 7b is an exploded view of the explosion-proof sheet and temperature sensing element of the second structure provided in the embodiment of this application;

[0032] Figure 7c is a cross-sectional view of the explosion-proof sheet and temperature sensing element of the second structure provided in the embodiment of this application;

[0033] Figure 8a is a schematic diagram of the third type of explosion-proof sheet and temperature sensor provided in the embodiment of this application;

[0034] Figure 8b is an exploded view of the explosion-proof sheet and temperature sensing element of the third structure provided in the embodiment of this application;

[0035] Figure 8c is a cross-sectional view of the explosion-proof sheet and temperature sensing element of the third structure provided in the embodiment of this application;

[0036] Figure 9a is a schematic diagram of the fourth type of explosion-proof sheet and temperature sensor provided in the embodiment of this application;

[0037] Figure 9b is an exploded view of the fourth type of explosion-proof sheet and temperature sensing element provided in the embodiments of this application;

[0038] Figure 9c is a cross-sectional view of the explosion-proof sheet and temperature sensing element of the fourth structure provided in the embodiment of this application;

[0039] Figure 10a is a schematic diagram of the fifth type of explosion-proof sheet and temperature sensing element provided in the embodiment of this application;

[0040] Figure 10b is an exploded view of the explosion-proof sheet and temperature sensing element of the fifth structure provided in the embodiment of this application;

[0041] Figure 10c is a cross-sectional view of the explosion-proof sheet and temperature sensing element of the fifth structure provided in the embodiment of this application;

[0042] Figure 11a is a schematic diagram of the sixth type of explosion-proof sheet and temperature sensing element provided in the embodiment of this application;

[0043] Figure 11b is an exploded view of the explosion-proof sheet and temperature sensing element of the sixth structure provided in the embodiment of this application;

[0044] Figure 11c is a cross-sectional view of the explosion-proof sheet and temperature sensing element of the sixth structure provided in the embodiment of this application;

[0045] Figure 12a is a schematic diagram of the seventh type of explosion-proof sheet and temperature sensing element provided in the embodiment of this application;

[0046] Figure 12b is an exploded view of the explosion-proof sheet and temperature sensing element of the seventh structure provided in the embodiment of this application;

[0047] Figure 12c is a cross-sectional view of the explosion-proof sheet and temperature sensing element of the seventh structure provided in the embodiment of this application;

[0048] Figure 13 is a top view of the explosion-proof sheet and temperature sensor provided in the embodiment of this application;

[0049] Figure 14 is a cross-sectional view of the explosion-proof sheet and temperature sensor provided in the embodiments of this application.

[0050] Explanation of reference numerals in the attached drawings: 100-Battery cover; 101-Main body; 102-Pressure relief hole; 110-Heat-conducting component; 111-First heat-conducting component; 112-Second heat-conducting component; 120-Temperature sensor; 121-First temperature sensor; 122-Second temperature sensor; 130-Weak part; 140-Explosion-proof sheet; 200-Battery; 210-Battery casing. Detailed Implementation

[0051] Power batteries, such as lithium-ion batteries, are a new type of rechargeable battery with advantages such as high energy density, high power density, light weight, and good safety, and have broad application prospects.

[0052] During prolonged or improper use, batteries may generate gas and excessive heat inside, causing the internal temperature to rise continuously and potentially leading to an explosion. Therefore, related technologies typically incorporate an explosion-proof valve on the battery. When the internal pressure increases to a certain value, the valve bulges outward under pressure, causing the weld between the valve and the aluminum casing to break. This opens the valve, cutting off the circuit current and creating an open circuit between the battery and the external environment, thus protecting the battery's safety.

[0053] However, in related technologies, the opening force of the explosion-proof valve is a fixed value, which cannot adequately meet the safety requirements of the battery under different operating conditions. Furthermore, the mechanical strength of the explosion-proof valve in these technologies is unaffected by temperature. The fixed opening force of the explosion-proof valve means that the opening force is preset during battery manufacturing, and the valve automatically opens when the internal pressure of the battery reaches the preset pressure.

[0054] For example, in related technologies, the explosion-proof valve does not need to open when the battery is working normally. However, due to the continuous compression inside the battery, the internal pressure increases. When the internal pressure increases to the preset pressure, the explosion-proof valve will open accidentally, affecting the normal operation of the battery. In addition, when the battery runs out of control, such as when the battery suffers mechanical damage causing a short circuit and the internal pressure of the battery increases, but the increased internal pressure has not yet reached the preset pressure, the explosion-proof valve cannot open in advance because the opening force is a fixed value. This causes the runaway battery to continuously transfer heat to the adjacent batteries, affecting the adjacent batteries. This cycle may cause the risk of overall runaway, which is detrimental to the safety of the battery.

[0055] To address the aforementioned technical problems, this application provides a battery cover and a battery, with a composite layer formed by a temperature sensor and a heat-conducting component. When the ambient temperature of the battery is lower than a preset temperature, the temperature sensor is less affected by the ambient temperature, and its critical value (mechanical strength) remains almost unchanged. This helps increase the opening force of the explosion-proof valve, thus preventing the risk of the explosion-proof valve opening accidentally due to increased internal pressure caused by external factors, ensuring the normal operation of the battery. Simultaneously, when the ambient temperature of the battery is higher than the preset temperature, the battery is in a runaway state. When the temperature exceeds the preset value, the critical pressure for rupture of the temperature sensor decreases with increasing temperature. This allows the explosion-proof valve to open earlier with a smaller opening force when the battery is runaway, helping to dissipate heat from the runaway battery sooner and mitigating or even blocking heat transfer from the runaway battery to adjacent batteries, thus maximizing battery safety.

[0056] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0057] Referring to Figures 1 to 5, this application embodiment provides a battery cover 100 for use as an explosion-proof sheet for a battery 200. The battery cover 100 may include a main body 101 and an explosion-proof sheet 140.

[0058] In this embodiment, the main body 101 is provided with a pressure relief hole 102 that extends through the thickness direction. This helps to prevent excessive internal pressure in the battery 200, thereby avoiding the risk of battery explosion or deformation.

[0059] In this embodiment, the explosion-proof sheet 140 is connected to the main body 101, and the explosion-proof sheet 140 covers the pressure relief hole 102 and has a weak part 130 for detonation.

[0060] In this embodiment, the shape and size of the weak portion 130 are not limited, and can be set according to actual needs. In addition, the formation method of the weak portion 130 on the main body 101 is not limited. For example, a groove can be formed on the main body 101 to form the weak portion 130.

[0061] In this embodiment, the weak part 130 is mainly described as an annular groove.

[0062] By incorporating the weak point 130, on the one hand, when the explosion-proof disc 140 opens, it can bear pressure evenly and crack along the weak point 130, opening outwards as a whole. This helps prevent fragments of the explosion-proof disc 140 from damaging other electrical components, thereby avoiding secondary damage. On the other hand, it weakens the structural strength of the explosion-proof disc 140, thus facilitating the rapid automatic opening of the explosion-proof disc 140.

[0063] In this embodiment, the explosion-proof plate 140 is also called a safety valve. Its main function is to automatically open the valve when the internal pressure or temperature of the battery 200 is too high, so as to directly dissipate the internal high-pressure gas, thereby achieving the purpose of explosion prevention and ensuring the safety of the battery 200.

[0064] It should be noted that when manufacturing battery 200, the first opening force of the explosion-proof plate 140 (the opening force when no temperature-sensitive material is used) can be preset. When the internal pressure of battery 200 reaches the preset pressure, the explosion-proof plate will automatically open. It can be understood that the first opening force is a fixed value.

[0065] In order to better meet the safety requirements of the battery 200 under different operating conditions, in this embodiment of the application, as shown in Figures 6a to 12c, the battery cover 100 may include a temperature sensing element 120.

[0066] In this embodiment of the application, the material used to manufacture the temperature sensor 120 is not limited.

[0067] For example, the temperature sensor 120, located near the cell of battery 200, can be made of an electrolyte-resistant material. For example, the temperature sensor 120 can be made of PE (Polyethylene); or PP (Polypropylene); or PET (Polyethylene terephthalate); or PPS (Polyphenylene Sulfide). All of these materials are solid at low temperatures and gradually soften and eventually melt at high temperatures.

[0068] For example, the side of the cell facing away from the battery 200 can be made of the material described above, or conventional plastics can be modified for use. This embodiment does not limit this.

[0069] A heat-conducting element 110 may be provided on the main body 101. The heat-conducting element 110 may be made of a metal material, and the material of the heat-conducting element 110 is not limited. For example, the material of the heat-conducting element 110 may be steel, copper, or aluminum. This embodiment does not limit this. Thus, compared with ordinary plastic explosion-proof valves, the explosion-proof valve of this application has advantages such as high temperature resistance and strong impact resistance.

[0070] It should be noted that the temperature sensing element 120 may have a second opening force, and the heat-conducting element 110 may have a third opening force. The third opening force of the heat-conducting element 110 and the second opening force of the temperature sensing element 120 are preset during the manufacturing of the battery 200. It can be understood that the third opening force is a fixed value, while the second opening force is a variable value. Specifically, the temperature sensing element 120 is adapted to reduce the critical rupture pressure as the temperature increases when the temperature exceeds a predetermined value.

[0071] Thus, when the ambient temperature of the battery 200 is lower than the preset temperature, the sum of the third opening force and the second opening force is greater than the first opening force, and the critical value (mechanical strength) of the temperature sensing element 120 remains almost unchanged. This helps to increase the overall opening force of the explosion-proof plate 140, thereby helping to avoid the risk of the explosion-proof plate 140 accidentally opening due to the increased internal pressure caused by external factors affecting the internal pressure of the battery 200, and ensuring the normal operation of the battery 200.

[0072] In this way, when the ambient temperature of the battery 200 is higher than the preset temperature, the battery 200 is in an uncontrolled state. The sum of the third opening force and the second opening force is less than the first opening force. When the temperature of the temperature sensor 120 is higher than the preset value, the critical pressure for rupture decreases as the temperature rises. In this way, the explosion-proof plate 140 can be opened earlier with a smaller opening force when the battery 200 is uncontrolled. This helps to remove the heat of the uncontrolled battery 200 earlier, and slows down or even blocks the problem of the uncontrolled battery 200 continuing to run away from the adjacent battery 200 due to heat transfer, thus ensuring the safety of the battery 200 to the greatest extent.

[0073] For example, when the internal temperature of battery 200 is within the normal temperature range, such as -20℃ to 60℃, the overall opening force of the explosion-proof plate 140 is enhanced (i.e., the first opening force). When the internal temperature of battery 200 rises and reaches an adjacent temperature, such as 60℃, the composite layer softens rapidly due to temperature influence after 60℃. After the composite layer softens rapidly, the second opening force of the temperature sensing element 120 does not play a major role, and the third opening force of the heat-conducting element 110 plays a major role. The third opening force of the heat-conducting element 110 is less than the first opening force of the explosion-proof plate, thereby causing the first opening force of the explosion-proof plate 140 to decrease rapidly and open the valve in time.

[0074] It should be noted that this embodiment does not specifically limit the preset temperature of battery 200, which can be set according to the actual situation.

[0075] In this embodiment, the temperature sensor 120 is connected to the heat conductor 110. When the explosion-proof plate is opened, it protrudes outward under force, which helps to prevent the temperature sensor 120 from disconnecting from the heat conductor 110. This avoids the problem that the opening force of the battery 200 during normal use cannot be increased by relying solely on the temperature sensor 120 or the heat conductor 110. This ensures that this application can increase the opening force of the explosion-proof plate 140 when the battery 200 is working normally, and decrease the opening force of the explosion-proof plate 140 when the battery 200 is out of control.

[0076] Therefore, the explosion-proof plate provided in this application embodiment can increase the opening force of the explosion-proof plate when the battery 200 is working normally, thereby helping to avoid the risk of the explosion-proof plate accidentally opening due to the increase of internal pressure caused by external factors affecting the internal pressure of the battery 200; at the same time, it can open the explosion-proof plate in advance with a small opening force when the battery 200 is out of control, thereby helping to remove the heat of the out-of-control battery 200 earlier, mitigating or even blocking the problem of the out-of-control battery continuing to run out of control by transferring heat to the adjacent batteries, and ensuring the safety of the battery 200 to the greatest extent.

[0077] In one feasible implementation, the connection method between the temperature sensor 120 and the heat conductor 110 is not limited. In this embodiment, the following three methods can be used as the main description.

[0078] In this embodiment, the temperature sensor 120 and the heat conductor 110 can be integrally molded using conventional injection molding. Conventional injection molding is a common plastic molding method that involves injecting molten plastic into a mold and then cooling and solidifying it within the mold, thereby achieving a high-strength bond between the temperature sensor 120 and the heat conductor 110.

[0079] In this embodiment, the temperature sensor 120 and the heat conductor 110 can be integrally formed by nano-injection molding. Nano-injection molding is a plastic molding method that combines metal and plastic, achieving integrated molding of the metal and plastic through nanotechnology. The nano-injection molding process may include special treatment of the metal surface to form nanoscale pits, and then injecting the treated metal and specially made nanoplastic together into a mold, allowing the plastic to fill the pits on the metal surface, thereby achieving a high-strength bond between the temperature sensor 120 and the heat conductor 110.

[0080] In this embodiment, the temperature sensor 120 and the heat conductor 110 can be bonded together. For example, the temperature sensor 120 and the heat conductor 110 can be bonded together with adhesive. Adhesive is a bonding material whose curing principle refers to transforming a colloidal adhesive into a strong and durable solid material through a chemical reaction or physical process, thereby achieving a high-strength bond between the temperature sensor 120 and the heat conductor 110.

[0081] It should be noted that the connection methods of the temperature sensor 120 and the heat conductor 110 in this embodiment include, but are not limited to, the three methods mentioned above. The specific connection method can be set according to the actual situation.

[0082] In one feasible implementation, the location of the temperature sensor on the main body 101 is not limited. For example, the main body 101 may include a first surface and a second surface, wherein the first surface is the side of the main body 101 closest to the battery cell of the battery 200, and the second surface is the side of the main body 101 opposite to the battery cell of the battery 200. The temperature sensor 120 may include a first temperature sensor 121 and a second temperature sensor 122, and the heat-conducting element 110 may include a first heat-conducting element 111 and a second heat-conducting element 112.

[0083] In the first embodiment, the temperature sensing element 120 may include only the first temperature sensing element 121, and the heat conducting element 110 may include only the first heat conducting element 111. The first temperature sensing element 121 is disposed in the weak portion 130 located on the first surface and is connected to the first heat conducting element 111.

[0084] It is understood that in this embodiment, the temperature sensor 120 is located on the side close to the battery cell. In this way, the overall opening force of the explosion-proof sheet 140 is increased from the inner surface of the explosion-proof sheet, thereby avoiding the risk of the explosion-proof sheet 140 being opened by mistake due to the increase in internal pressure caused by external factors affecting the internal pressure of the battery 200, and ensuring the normal operation of the battery 200.

[0085] The second embodiment is as follows: the temperature sensing element 120 may include only the second temperature sensing element 122, and the heat conducting element 110 may include only the second heat conducting element 112. The second temperature sensing element 122 is disposed in the weak part 130 located on the second surface and is connected to the second heat conducting element 112.

[0086] It is understood that in this embodiment, the temperature sensor 120 is located on the side away from the battery cell. In this way, the overall opening force of the explosion-proof sheet 140 is increased from the outer surface of the explosion-proof sheet, thereby avoiding the risk of the explosion-proof sheet 140 being opened by mistake due to the increase in internal pressure caused by external factors affecting the internal pressure of the battery 200, and ensuring the normal operation of the battery 200.

[0087] The third embodiment is as follows: the temperature sensing element 120 includes a first temperature sensing element 121 and a second temperature sensing element 122, and the heat conducting element 110 includes a first heat conducting element 111 and a second heat conducting element 112. The first temperature sensing element 121 is disposed in the weak portion 130 on the first surface and is connected to the first heat conducting element 111. The second temperature sensing element 122 is disposed in the weak portion 130 on the second surface and is connected to the second heat conducting element 112.

[0088] It is understood that in this embodiment, the temperature sensing element 120 is disposed on both sides of the main body 101. In this way, it acts from both the inner and outer surfaces of the explosion-proof sheet 140, and increases the overall opening force of the explosion-proof sheet 140. This avoids the risk of the explosion-proof sheet opening accidentally due to the internal pressure of the battery 200 being affected by external factors. This ensures the normal operation of the battery 200.

[0089] It should be noted that the placement of the temperature sensor on the main body 101 in this embodiment includes, but is not limited to, the three methods mentioned above, and can be set according to actual needs.

[0090] In one feasible implementation, the shape of the temperature sensor 120 is not limited. For example, the temperature sensor 120 may be a ring-shaped structure; or, the temperature sensor 120 may be a sheet-shaped structure. The heat-conducting element 110 may be a ring-shaped structure; or, the heat-conducting element 110 may be a sheet-shaped structure. The embodiments of this application can be described with reference to the following methods.

[0091] The first embodiment is as follows: Referring to Figures 6a to 6c, the first temperature sensing element 121 has a ring structure and surrounds the outer periphery of the first heat-conducting element 111.

[0092] The second embodiment is as follows: Referring to Figures 7a to 7c, the second temperature sensing element 122 has a ring structure and surrounds the outer periphery of the second heat-conducting element 112.

[0093] The third embodiment is as follows: Referring to Figures 8a to 8c, the first temperature sensing element 121 is a ring structure, the second temperature sensing element 122 is a ring structure, the first temperature sensing element 121 surrounds the outer periphery of the first heat-conducting element 111, and the second temperature sensing element 122 surrounds the outer periphery of the second heat-conducting element 112.

[0094] The fourth embodiment is as follows: Referring to Figures 10a to 10c, the first temperature sensing element 121 has a sheet-like structure and covers the weak part 130.

[0095] The fifth embodiment is as follows: the second temperature sensing element 122 is a sheet structure, and the second temperature sensing element 122 covers the weak part 130.

[0096] The sixth embodiment is as follows: Referring to Figures 12a to 12c, the first temperature sensor 121 is a sheet structure, the second temperature sensor 122 is a sheet structure, the first temperature sensor 121 covers the weak part 130, and the second temperature sensor 122 covers the weak part 130.

[0097] The seventh embodiment is as follows: Referring to Figures 9a to 9c and Figures 11a to 11c, one of the first temperature sensing element 121 and the second temperature sensing element 122 is an annular structure, correspondingly surrounding the outer periphery of one of the first heat-conducting elements 111 and the second heat-conducting element 112; the other of the first temperature sensing element 121 and the second temperature sensing element 122 is a sheet-like structure, and covers the corresponding weak portion 130.

[0098] It should be noted that the shape of the temperature sensor 120 in this embodiment includes, but is not limited to, the various shapes described above, and can be set according to actual needs.

[0099] In one feasible implementation, the thickness of the temperature sensor 120 is greater than the depth of the groove, which helps to ensure that the temperature sensor 120 can be completely located in the groove and helps to extend to the body 101 to connect with the heat conductor 110.

[0100] It should be noted that there are no specific limitations on the thickness of the temperature sensing element 120 and the groove depth; these can be set according to actual needs.

[0101] Referring to Figures 1 and 2, this embodiment of the application provides a battery 200, including a battery casing 210 and a battery cover 100, with the battery cover 100 covering the battery casing 210. In this embodiment, the battery casing 210 can be an aluminum casing, and the battery 200 can be a lithium-ion battery, a sodium-ion battery, etc., and this embodiment does not limit the specific type of battery.

[0102] Given that the battery in this embodiment includes the battery cover described in any of the above embodiments, the structure and beneficial effects of the battery including the battery cover will not be described in detail here.

[0103] Therefore, this application provides a battery cover and a battery. When the ambient temperature of the battery is lower than a preset temperature, the temperature sensor is less affected by the ambient temperature, and its critical value (mechanical strength) remains almost unchanged. This helps increase the opening force of the explosion-proof plate, thus avoiding the risk of the explosion-proof valve opening accidentally due to increased internal pressure caused by external factors, ensuring the normal operation of the battery. Simultaneously, when the ambient temperature of the battery is higher than the preset temperature, the battery is in a runaway state. When the temperature exceeds the preset value, the critical pressure of the temperature sensor decreases as the temperature rises. This allows the explosion-proof valve to open earlier with a smaller opening force when the battery is runaway, helping to remove heat from the runaway battery sooner and mitigating or even blocking the problem of heat transfer from the runaway battery to adjacent batteries, thus maximizing battery safety.

[0104] It should be noted that, in the description of the embodiments of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0105] In the description of the embodiments of this application, the term "and / or" merely indicates a relationship describing the associated objects, meaning that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the term "at least one" indicates any combination of at least two of a plurality of options, for example, including at least one of A, B, and C, which can represent any one or more elements selected from a set including communication between A, B, and C.

[0106] In the description of the embodiments of this application, the terms "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the term "multiple" means two or more, unless otherwise precisely specified.

[0107] In the description of the embodiments of this application, the terms "first," "second," "third," "fourth," etc. (if present) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A battery cover, characterized by The application relates to a temperature sensing device for a battery, comprising: a main body (101) provided with a pressure relief hole (102) penetrating through the thickness direction of the main body (101); an explosion-proof sheet (140) connected with the main body (101), the explosion-proof sheet (140) covering the pressure relief hole (102) and provided with a weak part (130) for explosion; a temperature sensing element (120) attached to the explosion-proof sheet (140) and covering the weak part (130) at least partially, the temperature sensing element (120) being adapted to reduce the rupture critical pressure with the increase of temperature when the temperature is greater than a predetermined value.

2. The battery cover of claim 1, wherein, The main body (101) is provided with a heat conducting element (110) connected with the temperature sensing element (120).

3. The battery cover of claim 2, wherein, The temperature sensing element (120) and the heat conducting element (110) are integrally formed by common injection molding or nano injection molding; or the temperature sensing element (120) and the heat conducting element (110) are heat-bonded.

4. The battery cover of claim 2 or 3, wherein, The main body (101) comprises a first surface, which is the side of the main body (101) close to the battery cell; The temperature sensing element (120) comprises a first temperature sensing element (121), and the heat conducting element (110) comprises a first heat conducting element (111); The first temperature sensing element (121) is attached to the weak part (130) on the first surface and connected with the first heat conducting element (111), and the first temperature sensing element (121) and the first heat conducting element (111) are arranged in a staggered manner on the first surface.

5. The battery cover of claim 4, wherein, The main body (101) comprises a second surface, which is the side of the main body (101) away from the battery cell; The temperature sensing element (120) comprises a second temperature sensing element (122), and the heat conducting element (110) comprises a second heat conducting element (112); The second temperature sensing element (122) is attached to the weak part (130) on the second surface and connected with the second heat conducting element (112), and the second temperature sensing element (122) and the second heat conducting element (112) are arranged in a staggered manner on the second surface.

6. The battery cover of claim 2 or 3, wherein, The weak part (130) is a groove formed on the explosion-proof sheet (140).

7. The battery cover of claim 5, wherein, The weak part (130) is an annular structure; The first temperature sensing element (121) is an annular structure, and the first temperature sensing element (121) surrounds the outer periphery of the first heat conducting element (111); And / or, the second temperature sensing element (122) is an annular structure, and the second temperature sensing element (122) surrounds the outer periphery of the second heat conducting element (112).

8. The battery cover of claim 5, wherein, The first temperature sensing element (121) is a sheet structure, and the first temperature sensing element (121) covers the weak part (130); And / or, the second temperature sensing element (122) is a sheet structure, and the second temperature sensing element (122) covers the weak part (130).

9. The battery cover of claim 5, wherein, One of the first temperature sensing element (121) and the second temperature sensing element (122) is an annular structure, and corresponds to the outer periphery of one of the first heat conducting element (111) and the second heat conducting element (112). The other of the first temperature sensing member (121) and the second temperature sensing member (122) is a sheet structure and covers the corresponding weak portion (130).

10. The battery cover of claim 2 or 3, wherein, The temperature sensing member (120) is close to one side of an electric core of a battery, and the temperature sensing member (120) comprises any one of a PP member, a PPS member or a PE member. And / or, the temperature sensing member (120) is away from one side of an electric core of a battery, and the temperature sensing member (120) comprises any one of a PP member, a PPS member, a PE member or a plastic member.

11. The battery cover of claim 2 or 3, wherein, The thickness of the temperature sensing member (120) is greater than the height of the weak portion (130), and the surface of the temperature sensing member (120) protrudes from the surface of the weak portion (130).

12. A battery, characterized by The battery cover is combined with the battery shell and encloses a cavity, and the electric core is located in the cavity.

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