Top cover structure and battery

Abstract

This utility model belongs to the field of battery structure technology and discloses a top cover structure and a battery. The top cover structure includes a cover plate, an explosion-proof valve, and an upper base. The cover plate has a valve mounting port through it along its thickness direction. The explosion-proof valve is fixedly installed in the valve mounting port to seal it. Along the thickness direction of the cover plate, the upper base is fixedly installed on the side of the cover plate away from the battery cell. The upper base and the cover plate are fixedly connected to limit the explosion-proof valve. The upper base is provided with a first vent opening. When the explosion-proof valve forms a vent under a preset pressure, the valve mounting port, the vent opening, and the first vent opening are connected. By limiting the explosion-proof valve with the upper base to seal the cover plate, defects such as incomplete welding and broken welding caused by welding the explosion-proof valve are avoided. It also avoids the need for annealing the explosion-proof valve, which is integrally installed on the cover plate. This ensures stable pressure relief performance, simplifies the manufacturing process, reduces production difficulty, and greatly improves production efficiency and costs.

Description

Technical Field

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

[0002] With the popularization of new energy vehicles and the rapid development of power batteries, in order to improve the safety performance of power batteries, stainless steel casings are now commonly used for battery cells. Stainless steel casings can better protect the current collectors inside the battery cells, prevent damage, and provide stronger physical protection.

[0003] However, during the battery cell manufacturing process, the high strength of the stainless steel casing results in a high burst pressure value for the explosion-proof valve integrated into it, leading to poor stability and stringent annealing conditions, thus increasing production costs. Furthermore, due to the material's high strength, the residual thickness of the groove in the explosion-proof valve is relatively low to ensure a sufficiently low burst pressure, making it prone to cracking during the finished product manufacturing process. The explosion-proof valve is the "last line of defense" for thermal runaway management of the power battery, preventing explosions through rapid pressure relief and directly impacting the safety performance of electric vehicles.

[0004] Based on the above, there is an urgent need for a top cover structure and battery to at least solve one of the aforementioned technical problems. Utility Model Content

[0005] The purpose of this invention is to provide a top cover structure and battery that have stable pressure relief performance, are easy to manufacture, and are easy to produce.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] Top cover structure, including:

[0008] A cover plate, wherein a valve mounting port is provided through the cover plate along its thickness direction;

[0009] An explosion-proof valve is fixedly installed in the valve mounting port to seal the valve mounting port;

[0010] The upper base is fixedly disposed on the side of the cover plate away from the battery cell along the thickness direction of the cover plate. The upper base and the cover plate are fixedly connected to limit the explosion-proof valve. The upper base is provided with a first vent opening. The first vent opening is configured such that when the explosion-proof valve forms a vent under a preset pressure, the valve mounting port, the vent opening and the first vent opening are connected.

[0011] In some embodiments, the explosion-proof valve has a fixing flange, and the upper base and the cover plate clamp and limit the fixing flange to fix the explosion-proof valve.

[0012] In some embodiments, the fixing flange extends continuously along the circumferential direction of the explosion-proof valve at the edge of the explosion-proof valve.

[0013] The top cover structure also includes a sealing ring, which is sealed between the fixing flange and the cover plate.

[0014] In some embodiments, the valve mounting port is a stepped opening, including a first stepped hole and a second stepped hole. The first stepped hole and the second stepped hole are connected along the thickness direction of the cover plate. The first stepped hole is located on the side of the second stepped hole away from the battery cell. A stepped surface is formed between the first stepped hole and the second stepped hole. The stepped surface is used to cooperate with the upper base to clamp and fix the explosion-proof valve.

[0015] In some embodiments, the top cover structure further includes a valve protection plate, which is fixedly connected to the upper base to seal the first vent opening.

[0016] In some embodiments, the upper base is provided with a first mounting hole, the cover plate is provided with a threaded hole, and the top cover structure further includes a threaded connector. The threaded connector passes through the first mounting hole and the threaded hole in sequence to fix the upper base and the cover plate together, and the threaded hole is provided with sealant.

[0017] In some embodiments, the top cover structure further includes a lower base, which is disposed along the thickness direction of the cover plate on the side of the cover plate close to the battery cell. The lower base and the cover plate are fixedly connected to each other to fix the explosion-proof valve between the lower base and the upper base.

[0018] In some embodiments, the lower base is further provided with a vent slot, the vent slot extending through the lower base along the thickness direction of the cover plate, and...

[0019] Along the thickness direction of the cover plate, the projection of the groove of the explosion-proof valve and the venting groove at least partially overlap.

[0020] In some embodiments, the cover plate is made of stainless steel, and the explosion-proof valve is made of aluminum or plastic.

[0021] A battery includes a casing, a cell, and the aforementioned top cover structure, wherein the top cover structure and the casing are sealed together and define a receiving space, and the cell is disposed within the receiving space.

[0022] The beneficial effects of the top cover structure and battery of this utility model are as follows: In this top cover structure, the explosion-proof valve is set by limiting the upper base to seal the cover plate, thereby achieving the effect of fixing the explosion-proof valve. This avoids the defects such as false welding and broken welding caused by welding the explosion-proof valve. It also avoids the need to anneal the explosion-proof valve that is integrated into the cover plate. This ensures the stability of the pressure relief performance, simplifies the manufacturing process, reduces the production difficulty, and greatly improves production efficiency and production cost. Attached Figure Description

[0023] Figure 1 This is a perspective view of the top cover structure provided by this utility model;

[0024] Figure 2 This is a partial exploded view of the top cover structure provided by this utility model;

[0025] Figure 3 This is a top view of the explosion-proof valve in the top cover structure provided by this utility model;

[0026] Figure 4 yes Figure 2 A magnified view of a section at point A in the middle;

[0027] Figure 5 yes Figure 2 A magnified view of a section at point B in the middle;

[0028] Figure 6 This is a bottom view of the top cover structure provided by this utility model;

[0029] Figure 7 yes Figure 6 A magnified view of a section at point C.

[0030] In the picture:

[0031] 1. Cover plate; 10. Valve mounting port; 101. First stepped hole; 1011. Mounting groove; 102. Second stepped hole; 11. Threaded hole;

[0032] 2. Upper base; 21. First ventilation opening; 22. First mounting hole;

[0033] 3. Valve protection plate;

[0034] 4. Explosion-proof valve; 41. Fixing flange; 42. Score;

[0035] 5. Sealing ring;

[0036] 6. Lower base; 61. Ventilation slot; 62. Second mounting hole. Detailed Implementation

[0037] 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.

[0038] 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.

[0039] 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.

[0040] In the description of this embodiment, the terms "upper," "lower," "right," and "left," 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.

[0041] The following is based on the appendix Figure 1 To be continued Figure 7 This invention introduces the top cover structure provided by the present invention.

[0042] like Figure 1 , Figure 2 As shown, in this embodiment, the top cover structure includes a positive aluminum block, a positive plastic plate, a cover plate 1, a positive electrode post, an upper base 2, an explosion-proof valve 4, a negative aluminum block, a negative plastic plate, and a negative electrode post. The positive aluminum block, positive plastic plate, positive electrode post, negative aluminum block, negative plastic plate, and negative electrode post are similar in structure to those in related batteries, and will not be described in detail in this invention.

[0043] Compared to the cover plate 1 of the relevant battery, in this embodiment, the cover plate 1 has a valve mounting port 10 along its thickness direction. The explosion-proof valve 4 is fixedly installed in the valve mounting port 10 and sealed to the cover plate 1, thereby sealing the valve mounting port 10. Along the thickness direction of the cover plate 1, the upper base 2 is located on the side of the cover plate 1 away from the battery cell, and the upper base 2 is fixedly connected to the cover plate 1 to limit the explosion-proof valve 4 and prevent the explosion-proof valve 4 from moving and losing its sealing and pressure relief functions. In addition, the upper base 2 is also provided with a first vent opening 21. When the battery cell experiences thermal runaway and the explosion-proof valve 4 is subjected to a preset pressure, the explosion-proof valve 4 can rupture and form a vent. At this time, the valve mounting port 10, the vent opening, and the first vent opening 21 are connected, so that both sides of the cover plate 1 can be connected through the valve mounting port 10, the vent opening, and the first vent opening 21 to achieve the effect of releasing gas and reducing pressure.

[0044] In this top cover structure, the explosion-proof valve 4 is set by the upper base 2 to seal the cover plate 1, thereby achieving the effect of fixing the explosion-proof valve 4. This avoids the defects such as false welding and broken welding caused by welding the explosion-proof valve 4, and also avoids the need to anneal the explosion-proof valve 4 which is integrally set on the cover plate 1. This ensures the stability of the pressure relief performance, simplifies the manufacturing process, reduces the production difficulty, and can greatly improve production efficiency and production cost.

[0045] like Figure 2 As shown, the upper base 2 is provided with a first mounting hole 22, and the cover plate 1 is provided with a threaded hole 11. The top cover structure also includes a threaded connector, which passes through the first mounting hole 22 and the threaded hole 11 in sequence to fix the upper base 2 and the cover plate 1 together, thereby achieving a limiting and abutting effect on the explosion-proof valve 4. Furthermore, sealant is provided in the threaded hole 11 to fill tiny gaps and prevent liquid and gas penetration. When the battery reaches its scheduled maintenance period or the explosion-proof valve 4 fails, the explosion-proof valve 4 can be replaced by disassembling the threaded connector and the upper base 2, thus enabling the utilization of other parts of the battery structure and avoiding the phenomenon of complete scrapping and irreparable damage.

[0046] Optionally, the top cover structure also includes a valve protection plate 3, which is fixedly connected to the upper base 2 to seal the first vent opening 21. The valve protection plate 3 can be adhesively installed on the upper base 2, thereby sealing the first vent opening 21 and preventing foreign objects such as electrolyte and water from contacting the explosion-proof valve 4, thus providing a protective effect.

[0047] Preferably, in this embodiment, the cover plate 1 is made of stainless steel to ensure the overall structural strength. The explosion-proof valve 4 is made of aluminum or plastic. Compared to materials such as stainless steel, aluminum or plastic has lower strength, which can prevent the explosion-proof valve 4 from having a high burst pressure value. Furthermore, due to its lower strength, the aluminum or plastic explosion-proof valve 4 has a higher residual thickness of the notch 42, making it less prone to accidental breakage and the formation of a vent during use. For example, in this embodiment, the explosion-proof valve 4 is made of aluminum with a thickness of 0.45-0.6 mm, and the residual thickness of the notch 42 is 0.13-0.17 mm.

[0048] Continue to refer to Figure 2 As shown, in this embodiment, the explosion-proof valve 4 has a fixing flange 41, and the upper base 2 and the cover plate 1 can clamp and limit the fixing flange 41, thereby fixing the explosion-proof valve 4 and making the explosion-proof valve 4 stably installed in the valve mounting port 10.

[0049] Specifically, such as Figure 3 As shown, the explosion-proof valve 4 has a middle portion and an edge portion. A fixing flange 41 extends continuously along the circumferential direction of the explosion-proof valve 4 at its edge position, forming the edge portion of the explosion-proof valve 4. The middle portion of the explosion-proof valve 4 is a sealed solid with a predetermined thickness, and the aforementioned groove 42 is provided between the middle portion and the edge portion. The groove 42, acting as a weak point, can rupture under predetermined pressure, causing the middle portion and the edge portion to separate, thereby forming the aforementioned vent.

[0050] Preferably, the top cover structure further includes a sealing ring 5, which is sealed between the fixing flange 41 and the cover plate 1. Under the abutment and limiting action of the upper base 2, the sealing ring 5 is clamped between the fixing flange 41 and the cover plate 1, thereby achieving a good sealing effect.

[0051] Specifically, such as Figure 4 As shown, the valve mounting port 10 is a stepped opening, including a first stepped hole portion 101 and a second stepped hole portion 102. The first stepped hole portion 101 and the second stepped hole portion 102 are connected along the thickness direction of the cover plate 1. The first stepped hole portion 101 is located on the side of the second stepped hole portion 102 away from the battery cell. The size of the first stepped hole portion 101 is larger than that of the second stepped hole portion 102, thereby forming a stepped surface between the first stepped hole portion 101 and the second stepped hole portion 102. The stepped surface is used to cooperate with the upper base 2 to clamp and fix the explosion-proof valve 4.

[0052] Optionally, such as Figure 4 As shown, an installation groove 1011 is provided on the stepped surface. The cross-sectional shape of the installation groove 1011 is semi-circular or U-shaped, which can be used to install the sealing ring 5 to achieve a better sealing effect.

[0053] like Figure 2 , Figure 5 As shown, the top cover structure also includes a lower base 6, which is disposed along the thickness direction of the cover plate 1 on the side of the cover plate 1 close to the battery cell. The lower base 6 and the cover plate 1 are fixedly connected to each other to fix the explosion-proof valve 4 between the lower base 6 and the upper base 2. Specifically, the lower base 6 is provided with a second mounting hole 62, and the cover plate 1 is provided with a threaded hole 11. The threaded connector passes through the second mounting hole 62 and the threaded hole 11 in sequence to fix the lower base 6 and the cover plate 1.

[0054] Of course, in some other embodiments, a through hole can be provided in the upper base 2, and a threaded hole 11 can be provided in the lower base 6. A threaded connector can then pass through the upper base 2 and the cover plate 1 and be connected to the lower base 6 through the threaded hole 11, thereby fixing the lower base 6. Therefore, the fixing method of the lower base 6 is not limited in this invention, as long as it can achieve the fixing of the lower base 6, the cover plate 1, the upper base 2, and the explosion-proof valve 4. Similarly, sealant is also provided in the threaded hole 11 used to fix the lower base 6 to prevent leakage of liquid or gas.

[0055] Preferably, such as Figure 6 , Figure 7 As shown, the lower base 6 is also provided with a vent slot 61, which extends through the lower base 6 along the thickness direction of the cover plate 1. Furthermore, the lower base 6 has multiple vent slots 61 arranged such that the projection of the notch 42 of the explosion-proof valve 4 and the vent slot 61 at least partially overlap along the thickness direction of the cover plate 1. When the battery cell generates air pressure, the air pressure acts on the notch 42 of the explosion-proof valve 4 through the vent slot 61 of the lower base 6. Compared to a top cover structure without a lower base 6, this top cover structure has a smaller air pressure application area, resulting in a greater force acting on the notch 42. This makes the explosion-proof valve 4 easier to open, requiring a lower burst pressure value. Under the same burst pressure requirement, the explosion-proof valve 4 in this top cover structure can have a thicker notch 42, thereby improving the yield rate in the production process.

[0056] In this top cover structure, the explosion-proof valve 4 is fixed by threaded connectors instead of welding, which improves production efficiency and yield. Furthermore, regular maintenance and replacement of the explosion-proof valve 4 can reduce the safety risks caused by performance degradation, extending the long-term lifespan of the power battery or enabling battery repair. Both aluminum and plastic explosion-proof valves 4 can be used, offering advantages such as low cost, high manufacturing yield, and low and stable burst pressure values. Because the material has lower strength than steel, the notch 42 can be made thicker to meet the same burst pressure requirements, thereby improving production yield and product reliability.

[0057] This utility model also provides a battery, which includes a casing, a battery cell, and the aforementioned top cover structure. The top cover structure and the casing are sealed together and define a receiving space. The battery cell is disposed within the receiving space and is electrically connected to the positive and negative terminals of the top cover structure. In this battery, the explosion-proof valve 4 is fixed by the upper base 2 to seal the cover plate 1, thus achieving the effect of fixing the explosion-proof valve 4. This avoids defects such as incomplete welding and broken welding caused by welding the explosion-proof valve 4, and also avoids the need for annealing the explosion-proof valve 4 integrally disposed on the cover plate 1. Therefore, it not only ensures the stability of the pressure relief performance, but also simplifies the manufacturing process, reduces production difficulty, and can greatly improve production efficiency and production costs.

[0058] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0059] 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 roof structure, characterized in that include: A cover plate (1) is provided with a valve mounting port (10) through it along its thickness direction; An explosion-proof valve (4) is fixedly installed in the valve mounting port (10) to seal the valve mounting port (10); The upper base (2) is fixedly disposed on the side of the cover plate (1) away from the battery cell along the thickness direction of the cover plate (1). The upper base (2) and the cover plate (1) are fixedly connected to limit the explosion-proof valve (4). The upper base (2) is provided with a first vent opening (21). The first vent opening (21) is configured such that when the explosion-proof valve (4) forms a vent under a preset pressure, the valve mounting port (10), the vent, and the first vent opening (21) are connected.

2. The top cover structure according to claim 1, characterized in that, The explosion-proof valve (4) has a fixing flange (41), and the upper base (2) and the cover plate (1) clamp and limit the fixing flange (41) to fix the explosion-proof valve (4).

3. The top cover structure according to claim 2, characterized in that, The fixing flange (41) extends continuously along the circumferential direction of the explosion-proof valve (4) at the edge of the explosion-proof valve (4). The top cover structure also includes a sealing ring (5), which is sealed between the fixing flange (41) and the cover plate (1).

4. The top cover structure according to claim 3, characterized in that, The valve mounting port (10) is a stepped opening and includes a first stepped hole (101) and a second stepped hole (102). The first stepped hole (101) and the second stepped hole (102) are connected along the thickness direction of the cover plate (1). The first stepped hole (101) is located on the side of the second stepped hole (102) away from the battery cell. A stepped surface is formed between the first stepped hole (101) and the second stepped hole (102). The stepped surface is used to cooperate with the upper base (2) to clamp and fix the explosion-proof valve (4).

5. The top cover structure according to claim 1, characterized in that, The top cover structure also includes a valve protection plate (3), which is fixedly connected to the upper base (2) to seal the first vent opening (21).

6. The top cover structure according to claim 1, characterized in that, The upper base (2) is provided with a first mounting hole (22), the cover plate (1) is provided with a threaded hole (11), and the top cover structure also includes a threaded connector. The threaded connector passes through the first mounting hole (22) and the threaded hole (11) in sequence to fix the upper base (2) and the cover plate (1) together, and the threaded hole (11) is provided with sealant.

7. The top cover structure according to claim 1, characterized in that, The top cover structure also includes a lower base (6), which is disposed along the thickness direction of the cover plate (1) on the side of the cover plate (1) close to the battery cell. The lower base (6) and the cover plate (1) are fixedly connected to fix the explosion-proof valve (4) between the lower base (6) and the upper base (2).

8. The top cover structure according to claim 7, characterized in that, The lower base (6) is also provided with a vent slot (61), which is provided through the lower base (6) along the thickness direction of the cover plate (1), and, Along the thickness direction of the cover plate (1), the projection of the groove (42) of the explosion-proof valve (4) and the vent (61) at least partially overlap.

9. The top cover structure according to any one of claims 1-8, characterized in that, The cover plate (1) is made of stainless steel, and the explosion-proof valve (4) is made of aluminum or plastic.

10. A battery characterized by The device includes a housing, a battery cell, and a top cover structure as described in any one of claims 1-9, wherein the top cover structure and the housing are sealed together and define a receiving space, and the battery cell is disposed within the receiving space.

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