Battery cover plate and single battery

Abstract

The utility model belongs to the technical field of batteries, and discloses a battery cover plate and a single battery. The battery cover plate comprises a cover plate body, an anti-explosion valve and a plurality of shielding pieces, the cover plate body comprises a sealing surface used for being in sealing connection with an opening of a battery shell, and a pressure relief hole is formed in the cover plate body; the anti-explosion valve is arranged in the pressure relief hole in a matched mode. The shielding pieces are arranged on the sealing face, the pressure relief hole is formed between any two adjacent shielding pieces, and the height of the shielding pieces protruding out of the sealing face is a first preset value. According to the battery cover plate, through the arrangement of the shielding piece, when the single battery is in thermal runaway, the core package assembly cannot shield the anti-explosion valve, so that the pressure relief of the anti-explosion valve cannot be influenced, and the use safety of the single battery using the battery cover plate is ensured.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery cover and a single battery cell. Background Technology

[0002] With the increasing maturity of lithium-ion battery technology, lithium-ion batteries have become the representative of modern high-performance batteries due to their advantages such as high working voltage, high specific energy, large capacity, low self-discharge, good cycle performance, long service life, light weight, and small size. They are widely used as power batteries in electric vehicles and energy storage fields. Therefore, the requirements for the performance and safety of lithium-ion batteries are increasing.

[0003] Current battery structures are generally short, and the potential for overall capacity improvement is limited by manufacturing processes. Therefore, battery structures are evolving towards longer batteries. Longer lithium-ion batteries are typically designed with tabs on both sides. Their structure includes: a cover plate (integrating terminals, explosion-proof valves, and electrolyte injection holes), a casing, a core pack, and electrolyte. The cover plate and casing, after welding, form a sealed space with sufficient mechanical strength to protect the core pack. The core pack is electrically connected to the cover plate's terminal bases via laser welding using tabs on both sides. The battery's length is primarily secured by a plastic insulating material pressed against the core pack beneath the cover plate. The cover plate integrates an explosion-proof valve structure, mainly used for the directional discharge of high-temperature, high-pressure gases inside the battery in the event of thermal runaway due to an internal short circuit, improving battery safety.

[0004] In the battery structure described above, the core pack is mainly insulated and fixed by the plastic under the cover plate along its length. However, the insulating material of this plastic is generally made of PP, which has very limited strength and high-temperature resistance, typically around 150℃. But the temperature at which the battery experiences thermal runaway is usually much higher than the melting point of these insulating materials. The plastic and other fixing structures inside the battery are prone to melting and failure. At this point, only the core pack remains inside the battery, leading to an increased gap between the core pack and the cover plate and casing. The core pack has a high degree of freedom inside the battery. As the high-temperature and high-pressure gas is vented directionally towards the explosion-proof valve, the core pack will move randomly with the high-temperature and high-pressure gas flow, blocking the explosion-proof valve on the cover plate and obstructing the venting channel. This greatly reduces the venting effect of the explosion-proof valve and reduces the safety performance of the battery.

[0005] Therefore, there is an urgent need to provide a new type of battery cover and single battery cell to solve the above-mentioned technical problems in the prior art. Utility Model Content

[0006] One objective of this invention is to provide a battery cover that prevents the cell pack assembly from obstructing the explosion-proof valve when a single cell experiences thermal runaway, thereby ensuring that the explosion-proof valve can reliably release pressure and guaranteeing the safety of the single cell using this battery cover.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] The battery cover includes a cover body, an explosion-proof valve, and several shielding components. The cover body includes a sealing surface for sealing connection with the opening of the battery casing, and the cover body has a pressure relief hole. The explosion-proof valve is disposed in the pressure relief hole. The shielding components are disposed on the sealing surface, and the pressure relief hole is disposed between any two adjacent shielding components. The height of the shielding component protruding from the sealing surface is a first preset value.

[0009] Optionally, the aforementioned shielding member includes a shielding portion and a supporting portion. The supporting portion is disposed around the outer periphery of the shielding portion so that the supporting portion and the shielding portion form a shielding space. One end of the supporting portion is connected to the sealing surface, and the other end is connected to the shielding portion. The height of the supporting portion is the aforementioned first preset value.

[0010] Optionally, the aforementioned shielding portion is provided with a plurality of pressure relief through holes, and / or the aforementioned support portion is provided with a plurality of pressure relief through holes.

[0011] Optionally, the support portion includes a plurality of support feet, and the shielding portion, the sealing surface, and the space between two adjacent support feet form the pressure relief through hole.

[0012] Optionally, 2N shielding members are provided, and the 2N shielding members are distributed symmetrically about the pressure relief hole axis along the first direction.

[0013] Optionally, two shielding members are provided, and the minimum distance between the two shielding members along the first direction is B, the first preset value is H, and H / B≥0.05.

[0014] Optionally, the maximum dimension of the pressure relief hole along the second direction is A, and the dimension of the shielding member along the second direction is C, where C > 1.3A; the first direction is perpendicular to the second direction.

[0015] Optionally, the dimension of the cover plate body along the second direction is D, 55% ≤ C / D ≤ 80%, and (DC) / 2 > 3mm.

[0016] Optionally, the battery cover further includes an insulating member disposed on the sealing surface, and the shielding member is sandwiched between the insulating member and the sealing surface.

[0017] Another objective of this invention is to provide a single-cell battery, which includes a battery cover as described in any of the above embodiments.

[0018] Beneficial effects:

[0019] In this embodiment, the battery cover has pressure relief holes on its body, and an explosion-proof valve is installed within these holes. When a single battery cell using this cover experiences thermal runaway, the explosion-proof valve releases pressure. Several shielding components are positioned on the sealing surface of the cover body to block the cell pack assembly inside the battery casing, preventing the cell pack assembly from clogging the explosion-proof valve and causing delayed pressure release. This prevents safety hazards caused by excessive internal pressure in the battery cell. Furthermore, the pressure relief holes are located between adjacent shielding components, allowing high-pressure gas to flow to the explosion-proof valve through the space between them, ensuring that the shielding components do not interfere with the normal explosion-proof pressure release function of the valve. Through the shielding components, this battery cover ensures that the cell pack assembly does not block the explosion-proof valve during thermal runaway, thus preventing any impact on the valve's pressure release and guaranteeing the safety of the single battery cell using this cover. Attached Figure Description

[0020] Figure 1 This is an isometric view of the battery cover provided in a specific embodiment of this utility model;

[0021] Figure 2 This is a bottom view of the battery cover provided in a specific embodiment of this utility model;

[0022] Figure 3 This is an isometric view of the shielding component provided in a specific embodiment of this utility model.

[0023] In the picture:

[0024] 100. Cover plate body; 110. Sealing surface; 120. Pressure relief hole;

[0025] 200. Explosion-proof valve;

[0026] 300, shielding component; 301, pressure relief through hole; 302, shielding space; 310, shielding part; 320, support part; 321, support foot. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0028] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to 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 utility model based on the specific circumstances.

[0029] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0030] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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 utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0031] The first direction described in this embodiment is: Figure 1 and Figure 2 The X direction shown is the length direction of the cover plate body 100, and the second direction is... Figure 1 and Figure 2 The Y direction shown is the width direction of the cover body 100; the first direction is perpendicular to the second direction.

[0032] like Figure 1 and Figure 2 As shown, the battery cover includes a cover body 100, an explosion-proof valve 200, and a plurality of shielding members 300. The cover body 100 includes a sealing surface 110 for sealing connection with the opening of the battery casing, and the cover body 100 has a pressure relief hole 120. The explosion-proof valve 200 is disposed in the pressure relief hole 120. The shielding members 300 are disposed on the sealing surface 110, and the pressure relief hole 120 is disposed between any two adjacent shielding members 300. The height of the shielding member 300 protruding from the sealing surface 110 is a first preset value.

[0033] In this embodiment, the battery cover has a pressure relief hole 120 on the cover body 100, and an explosion-proof valve 200 is installed in the pressure relief hole 120. When a single battery cell using this battery cover experiences thermal runaway, the explosion-proof valve 200 releases pressure. Several shielding members 300 are installed on the sealing surface 110 of the cover body 100, which can block the core pack assembly inside the battery casing, preventing the core pack assembly from blocking the explosion-proof valve 200 and causing the explosion-proof valve 200 to release pressure in a timely manner, thus preventing the battery cell from having safety hazards due to excessive internal pressure. Furthermore, the pressure relief hole 120 is provided between two adjacent shielding members 300, and the high-pressure gas during pressure relief flows to the explosion-proof valve 200 through the space between two adjacent shielding members 300, so that the shielding members 300 do not affect the normal explosion-proof pressure relief of the explosion-proof valve 200. The battery cover, through the setting of the shielding component 300, ensures that the cell pack assembly will not block the explosion-proof valve 200 when a single cell experiences thermal runaway, thereby not affecting the pressure relief of the explosion-proof valve 200 and ensuring the safety of the single cell using this battery cover.

[0034] Optionally, 2N shielding members 300 are provided, and the 2N shielding members 300 are symmetrically distributed along the first direction about the pressure relief hole 120. That is, an even number of shielding members 300 are provided, and the even number of shielding members 300 are symmetrically distributed about the explosion-proof valve 200, thereby supporting the cell pack assembly inside the single battery on both sides of the explosion-proof valve 200, ensuring the evenness of the support force, preventing the cell pack assembly from tilting and blocking the explosion-proof valve 200 during thermal runaway, and ensuring that the normal pressure relief function of the explosion-proof valve 200 is not affected.

[0035] It should be noted that the number of shielding members 300 can also be odd, as long as the shielding members 300 are distributed on both sides of the pressure relief hole 120. For example, since the pressure relief hole 120 is not located at the center of the cover plate body 100, the space on both sides of the pressure relief hole 120 along the first direction is not equal. Therefore, different numbers of shielding members 300 can be provided on both sides of the pressure relief hole 120 along the first direction. This will not be elaborated here.

[0036] Furthermore, such as Figure 1 and Figure 2 As shown, two shielding members 300 are provided. The minimum distance between the two shielding members 300 along the first direction is B, and the first preset value is H, where H / B ≥ 0.05. This ensures the supporting effect of the two shielding members 300 on the core pack assembly, guarantees sufficient support height, and prevents the core pack assembly from blocking the explosion-proof valve 200 due to deformation, thereby improving the reliability and safety of the battery cover.

[0037] Optionally, the maximum dimension of the pressure relief hole 120 along the second direction is A, and the dimension of the shielding member 300 along the second direction is C, where C > 1.3A; the first direction is perpendicular to the second direction. This arrangement ensures the smooth operation of the explosion-proof valve 200, prevents the exhaust passage of the explosion-proof valve 200 from being blocked, and improves the exhaust and pressure relief effect of the explosion-proof valve 200.

[0038] In this embodiment, the dimension of the cover plate body 100 along the second direction is D, 55% ≤ C / D ≤ 80%, and (DC) / 2 > 3mm. If the dimension C is too small, it will affect the supporting effect of the shielding member 300. If the dimension C is too large, the distance between the shielding member 300 and the edge of the cover plate body 100 will be too small, which will affect the assembly of the battery cover and the battery casing and affect the assembly yield.

[0039] The following table details the impact of the specific values ​​of the above parameters on the explosion-proof pressure relief function and safety of a single battery cell. All values ​​in the table are in mm.

[0040]

[0041] Therefore, in order to ensure that the shielding component 300 supports the core pack assembly and ensures the pressure relief effect of the explosion-proof valve 200, it is necessary to meet the following conditions: H / B≥0.05, 55%≤C / D≤80%, and C>1.3A; so that the battery cover can provide good support for the core pack assembly while ensuring good pressure relief function, and ensure that the installation of the battery cover is not affected.

[0042] Optionally, the aforementioned shielding member 300 includes a shielding portion 310 and a supporting portion 320. The supporting portion 320 surrounds the outer periphery of the shielding portion 310 so that the supporting portion 320 and the shielding portion 310 form a shielding space 302. One end of the supporting portion 320 is connected to the sealing surface 110, and the other end is connected to the shielding portion 310. The height of the supporting portion 320 is the aforementioned first preset value. Using the shielding portion 310 to shield and support the cell pack assembly inside the battery can protect the explosion-proof valve 200. Furthermore, using the supporting portion 320 to support the shielding portion 310 prevents the shielding portion 310 from directly contacting the explosion-proof valve 200, thereby increasing the shielding space 302 formed by the shielding member 300. This further prevents the cell pack assembly from blocking the explosion-proof valve 200 and ensures that the explosion-proof valve 200 can release pressure normally.

[0043] Furthermore, the aforementioned shielding portion 310 is provided with a plurality of pressure relief through holes 301, and / or the aforementioned support portion 320 is provided with a plurality of pressure relief through holes 301. The pressure relief through holes 301 provided in the shielding portion 310 can connect the internal space of the single battery cell, the shielding space 302, and the pressure relief passage of the explosion-proof valve 200 from the wall surface of the shielding member 300 in contact with the core pack assembly, ensuring unobstructed pressure relief; while the pressure relief through holes 301 provided in the support portion 320 can connect the internal space of the single battery cell and the shielding space 302 from the circumference of the shielding member 300, so that even after the core pack assembly covers the pressure relief through holes 301 of the shielding portion 310 and the space between the two shielding members 300, pressure relief can still be carried out, further improving the safety of the battery cover.

[0044] In this embodiment, the support portion 320 includes a plurality of support legs 321, and the shielding portion 310, the sealing surface 110, and the space between two adjacent support legs 321 form the pressure relief through hole 301. By using the support legs 321 to support the shielding portion 310 and using the space between the support legs 321 to form the pressure relief through hole 301, the flow area of ​​the pressure relief through hole 301 can be increased, ensuring normal pressure relief of the pressure relief through hole 301 on the support portion 320.

[0045] Furthermore, the battery cover also includes an insulating component, which is disposed on the sealing surface 110. The shielding component 300 is sandwiched between the insulating component and the sealing surface 110. The insulating component is also the lower plastic component commonly used in the art, which will not be described in detail here.

[0046] Specifically, the shielding component 300 is made of aluminum sheet by stamping, and the cover plate body 100 is also made of aluminum sheet by stamping. The shielding component 300 is welded to the cover plate body 100.

[0047] The assembly process of the battery cover is as follows: 1. A light aluminum sheet is stamped and formed into a cover body 100; 2. The explosion-proof valve 200 is welded to the pressure relief hole 120 of the cover body 100; 3. An aluminum sheet is stamped and formed into a shielding component 300; 4. The shielding component 300 is welded to the sealing surface 110 of the cover body 100; 5. An insulating component is installed on the sealing surface 110.

[0048] This embodiment also provides a single-cell battery, which includes a battery cover as described in any of the above embodiments. The battery cover seals the opening of the battery casing, preventing the internal cell pack assembly from blocking the explosion-proof valve 200 in the event of thermal runaway. The shielding member 300 protects the explosion-proof valve 200, allowing it to perform normal explosion-proof and pressure-relieving functions, thus improving the safety of the single-cell battery. This single-cell battery can power battery packs, pure electric vehicles, hybrid electric vehicles, ships, and energy storage devices, etc., which will not be elaborated further here. These devices, powered by the single-cell battery, achieve all the beneficial effects of the single-cell battery and battery cover described above, which will not be elaborated further here.

[0049] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A battery cover, characterized in that, include: The cover plate body includes a sealing surface for sealing connection with the opening of the battery housing, and the cover plate body is provided with a pressure relief hole; An explosion-proof valve is fitted into the pressure relief port. A plurality of shielding components are disposed on the sealing surface, and a pressure relief hole is provided between any two adjacent shielding components. The height of the shielding component protruding from the sealing surface is a first preset value.

2. The battery cover according to claim 1, characterized in that, The shielding component includes a shielding part and a supporting part. The supporting part is arranged around the outer periphery of the shielding part so that the supporting part and the shielding part form a shielding space. One end of the supporting part is connected to the sealing surface, and the other end is connected to the shielding part. The height of the supporting part is the first preset value.

3. The battery cover according to claim 2, characterized in that, The shielding part has a plurality of pressure relief holes, and / or the supporting part has a plurality of pressure relief holes.

4. The battery cover according to claim 3, characterized in that, The support portion includes several support legs, and the shielding portion, the sealing surface, and the space between two adjacent support legs form the pressure relief through hole.

5. The battery cover according to claim 1, characterized in that, There are 2N shielding components, which are distributed symmetrically about the pressure relief hole axis along the first direction.

6. The battery cover according to claim 5, characterized in that, Two shielding components are provided, and the minimum distance between the two shielding components along the first direction is B, the first preset value is H, and H / B≥0.

05.

7. The battery cover according to claim 6, characterized in that, The maximum dimension of the pressure relief hole along the second direction is A, and the dimension of the shielding member along the second direction is C, where C > 1.3A; the first direction is perpendicular to the second direction.

8. The battery cover according to claim 7, characterized in that, The dimension of the cover plate body along the second direction is D, 55% ≤ C / D ≤ 80%, and (DC) / 2 > 3mm.

9. The battery cover according to any one of claims 1-8, characterized in that, The battery cover also includes an insulating component disposed on the sealing surface, and the shielding component is sandwiched between the insulating component and the sealing surface.

10. A single-cell battery, characterized in that, Includes the battery cover as described in any one of claims 1-9.

Images