Button cell

Abstract

The present application provides a button cell. The button cell comprises: a first substrate, a first annular wall, and a sealing member, wherein the first annular wall surrounds the first substrate, and the first annular wall and the first substrate define an accommodating cavity; the sealing member is at least partially located on the side of the first annular wall facing away from the accommodating cavity; a second casing comprises a second substrate and a second annular wall; the second substrate is configured to cover and seal the accommodating cavity; the second annular wall is connected to the periphery of the second substrate.

Description

button cell battery

[0001] This application claims priority to Chinese Patent Application No. 202421741017.8, filed with the Chinese Patent Office on July 22, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery technology, specifically to a button cell battery. Background Technology

[0003] Button cells, also known as coin cells, are generally larger in diameter and thinner in thickness. A button cell typically includes a positive terminal cap and a negative terminal cap; when assembling a button cell, the positive terminal cap must be attached to the negative terminal cap.

[0004] In related technologies, assembly pressure is generated during the assembly process of button cells. Invention Overview

[0005] Excessive assembly pressure can cause the negative electrode cap to bend, affecting battery performance and lifespan.

[0006] This application provides a button cell battery. The button cell battery includes: a first housing assembly, including a first substrate, a first annular wall, and a seal, wherein the first annular wall is disposed around the periphery of the first substrate and forms a receiving cavity with the first substrate, and at least a portion of the seal is located on the side of the first annular wall opposite to the receiving cavity;

[0007] The second housing includes a second substrate and a second annular wall. The second substrate is configured to cover and seal the receiving cavity. The first end of the second annular wall is connected to the periphery of the second substrate, and the second end of the second annular wall extends along a side away from the second substrate, configured to form a sealing structure with the sealing element and the first annular wall.

[0008] The sealing element includes a first end located on the side of the first annular wall away from the receiving cavity and close to the first substrate. The first end is provided with a first inclined surface, which is inclined relative to the first annular wall, and the overlapping end abuts against the first inclined surface. Beneficial effects

[0009] The button cell provided in this application, when the first housing assembly and the second housing are assembled, has a first inclined surface that is tilted relative to the first annular wall. According to the principle of force distribution in dynamics in theoretical mechanics, using an inclined surface at a certain angle can effectively reduce the horizontal compressive force and concentrate the force in the vertical direction, thereby preventing the first substrate of the first housing assembly from bending. At the same time, it has a better sealing effect, ensuring the sealing performance of the button cell, suppressing the evaporation of electrolyte in the button cell, and improving battery performance and battery life. Attached Figure Description

[0010] Figure 1 is a schematic diagram of the structure of a button cell provided in a possible implementation of this application.

[0011] Figure 2 is a cross-sectional view of one possible implementation of the button cell shown in Figure 1.

[0012] Figure 3 is a partial structural schematic diagram of the button cell shown in Figure 2.

[0013] Figure 4 is a partial structural schematic diagram of the button cell shown in Figure 2.

[0014] Figure 5 is a schematic diagram of the structure shown in Figure 3 without the second shell.

[0015] Figure 6 is a magnified view of part A in Figure 5.

[0016] Figure 7 is a cross-sectional view of a partial structure of another possible implementation of the button cell shown in Figure 1.

[0017] Figure 8 is a magnified view of part B in Figure 7.

[0018] Explanation of reference numerals in the attached figures:

[0019] 10. First housing assembly; 11. First substrate; 12. Receiving cavity; 13. First annular wall; 15. Seal; 154. Second sealing part; 152. First sealing part;

[0020] 1541, First end; 151, Second inclined plane; 1511, First end of the first inclined plane; 1513, Second end of the first inclined plane;

[0021] 153. First inclined plane; 156. First top surface; 158. Second top surface;

[0022] 30. Second housing; 31. Second substrate; 33. Second annular wall; 331. Overlapping end;

[0023] 60, negative electrode; 70, positive electrode; 80, diaphragm. Embodiments of the present invention

[0024] In the description of this application, unless otherwise expressly 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 application according to the specific circumstances.

[0025] In this application, unless otherwise expressly 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 being directly above or diagonally above the second feature, where the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, where the first feature is at a lower horizontal level than the second feature.

[0026] In the description of this embodiment, the terms "upper," "lower," "left," "right," "front," and "rear," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used 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 application. Furthermore, the terms "first" and "second" are used for distinction in description and have no special meaning.

[0027] This application provides a button cell battery. The following description will be provided in conjunction with the accompanying drawings.

[0028] The button cell provided in this application embodiment, referring to Figure 1, includes a first housing assembly 10 and a second housing 30. Referring to Figures 2 and 3, the first housing assembly 10 includes a first substrate 11, a first annular wall 13, and a sealing member 15. The first annular wall 13 is disposed around the periphery of the first substrate 11 and forms a receiving cavity 12 with the first substrate 11. The sealing member 15 should be made of an elastic material, such as rubber, silicone, or other soft rubber, or it can be made of plastic, such as polypropylene PP8830, polypropylene DX-23, DX-231, polytetrafluoroethylene, or other elastic fiber materials. The second housing 30 can be formed into the required shape by an integral stamping process.

[0029] In some embodiments, the first annular wall 13 may be perpendicular to the plane on which the first substrate 11 is located, and the plane on which the first substrate 11 is located may be a horizontal plane. In other embodiments, the first annular wall 13 may not be perpendicular to the plane on which the first substrate 11 is located.

[0030] The first annular wall 13 and the first substrate 11 can be integrally formed, for example, by stamping a metal plate to form the first annular wall 13 and the first substrate 11. In other specific embodiments, the first annular wall 13 and the first substrate 11 can also be connected by welding or other methods.

[0031] Referring to Figure 2, at least a portion of the sealing element 15 is disposed on the outer periphery of the first annular wall 13, specifically the side of the first annular wall facing away from the receiving cavity, thereby achieving a better sealing effect. Specifically, the sealing element 15 may include a first sealing portion 152 and a second sealing portion 154 connected to each other. The first sealing portion 152 is disposed within the receiving cavity 12, and the second sealing portion 154 is disposed on the side of the first annular wall 13 facing away from the receiving cavity 12. Therefore, during assembly, the sealing element 15 is less likely to move, resulting in a good sealing effect.

[0032] Referring to Figure 3, the second housing 30 may include a second substrate 31 and a second annular wall 33. The second substrate 31 is configured to cover and seal the receiving cavity 12. After the second housing 30 is assembled to the first housing assembly 10, the second annular wall 33 is located on the outer periphery of the first annular wall 13. Due to limitations in processing precision and cost, there may be a gap between the inner wall surface of the second annular wall 33 and the outer wall surface of the first annular wall 13. A sealing element 15 is provided, with at least a portion located between the first annular wall 13 and the second annular wall 33, thereby sealing the gap between the inner wall surface of the second annular wall 33 and the outer wall surface of the first annular wall 13, preventing external moisture and dust from entering the interior of the coin cell and affecting its performance.

[0033] Referring to Figure 3, in some embodiments, the second annular wall 33 is connected to the periphery of the second substrate 31, and the overlapping end 331 of the second annular wall 33 extends along the side away from the second substrate 31, forming a sealing structure with the sealing member 15 and the first annular wall 13. In some specific embodiments, the second annular wall 33 may be perpendicular to the plane where the second substrate 31 is located, and the plane where the second substrate 31 is located may be a horizontal plane. In other specific embodiments, the second annular wall 33 may not be perpendicular to the plane where the second substrate 31 is located.

[0034] Referring to Figure 3, the second sealing part 154 includes a first end 1541 near the first substrate 11. The first end 1541 is located on the side of the first annular wall 13 away from the receiving cavity and is disposed near the first substrate 11. The first end 1541 is provided with a first inclined surface 153. The first inclined surface 153 is inclined relative to the first annular wall 13 and abuts against the second housing 30. Specifically, the overlapping end 331 of the second annular wall 33 abuts against the first inclined surface 153.

[0035] In this embodiment, during the assembly of the first housing assembly 10 and the second housing 30, the first inclined surface 153 can disperse the assembly pressure during the battery sealing process, preventing the first substrate 11 of the first housing assembly 10 from bending. Simultaneously, the presence of the first inclined surface 153 improves the compression ratio and uniformity of the seal 15, thereby achieving a good sealing effect, ensuring the sealing performance of the coin cell, suppressing electrolyte evaporation in the coin cell, and improving battery performance and lifespan.

[0036] Depending on the actual needs, the inclined surface of the first end 1541 may include: an outer inclined surface, an inner inclined surface, an outer R-corner (rounded corner), etc.

[0037] In some specific embodiments, the inclined surface of the first end 1541 is configured as an outer inclined surface structure. For example, in Figures 2 to 6, the inclined surface of the first end 1541 (i.e., the first inclined surface 153) is always configured as an outer inclined surface structure. The angle α2 between the first inclined surface 153 and the plane where the second substrate 31 is located can be 32°~40°. When the angle is within the range of 32°~40°, the assembly force can be effectively distributed in the sealing process of the battery cell assembly. Furthermore, the outer inclined surface structure can guide the second housing 30, allowing the second housing 30 and the first housing assembly 10 to be assembled smoothly and accurately during the packaging process. The inner side of the second housing 30 is continuously and tightly fitted with the sealing element 15 to avoid misalignment during assembly and ensure positional accuracy. The angle α2 between the first inclined surface 153 and the plane where the second substrate 31 is located can be: 32°, 33°, 34°, 35°, 36°, 37°, 38°, 39°, or 40°.

[0038] In some specific embodiments, such as Figures 7 and 8, the inclined surface of the first end 1541 (i.e., the first inclined surface 153) is configured as an inner inclined surface structure. When the end of the seal 15 away from the second housing 30 is configured as an inner inclined surface, the range of the inner inclined angle (the angle a2 between the first inclined surface 153 and the plane where the second substrate 31 is located) can be 20°~40°, for example, it can be 20°, 25°, 26°, 27°, 28°, 29°, 30°, 33°, 34°, 35°, 36°, 37°, 38°, 39°, 40°.

[0039] In some specific embodiments, the inclined surface (i.e. the first inclined surface 153) of the first end 1541 is set as an outer R-corner rounded corner structure. The R value (or radius) of the outer R-corner rounded corner can be 0.2mm-0.8mm, specifically 0.3mm-0.8mm, for example: 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm.

[0040] In this embodiment, the inclined surface of the first end 1541 is configured as an outer inclined surface structure, thereby making the first substrate 11 have a smaller bending degree and a better effect of distributing the assembly force during the assembly process.

[0041] In this embodiment of the application, during the assembly of the second housing 30 (or positive electrode cover) to the first housing assembly 10 (or negative electrode integrated cover), the first inclined surface can distribute the assembly force. During the assembly process, the axial direction of the sealing element 15 is kept consistent with the axial direction of the second housing 30 (or positive electrode cover), ensuring that the sealing element 15 is centered in the second housing 30. This prevents the sealing element 15 from being misaligned after the coin cell is packaged, ensuring a larger contact area between the positive electrode and the second housing 30, resulting in better coin cell performance. The second housing 30 applies a uniform pressure to the periphery of the sealing element 15, allowing the periphery of the sealing element 15 to be uniformly compressed. This improves the compression ratio and uniformity of the sealing element 15, thereby improving the sealing performance, making the coin cell more leak-proof, effectively suppressing electrolyte evaporation, and preventing external moisture intrusion. Because the sealing element 15 applies a uniform pressure to the periphery of the first housing assembly 10, it effectively prevents the first substrate 11 in the first housing assembly 10 from bending. Since the assembly force generated during the sealing process comes from the horizontal extrusion force of the mold during the descent of the assembled battery cell, according to the principle of force distribution in dynamics in theoretical mechanics, using a certain angled inclined plane can effectively reduce the horizontal extrusion force, thereby making the first substrate 11 in the first housing assembly 10 less subjected to horizontal force and the force concentrated in the vertical direction, thus avoiding bending.

[0042] In some specific embodiments, referring to Figure 3, the first end 1541 may also include a first top surface 156, which is adjacent to the first annular wall 13. The first inclined surface 153 is connected to the end of the first top surface 156 away from the first annular wall 13. That is, in this embodiment, the first top surface 156 is located between the first annular wall 13 and the first inclined surface 153, and the first inclined surface 153 is located on the outside of the first end 1541, that is, on the side close to the second annular wall 33.

[0043] The inclination direction of the first inclined surface 153 can be as follows: it is inclined from the first top surface 156 toward the direction away from the first ring wall 13 and away from the first substrate 11, and the first inclined surface 153 is in contact with the second ring wall 33.

[0044] Referring to Figures 5 and 6, the angle between the first inclined surface 153 and the plane containing the first annular wall 13 is a1, and the angle between the first inclined surface 153 and the plane containing the second substrate 31 is a2. a1 and a2 are different. Thus, the first inclined surface 153 has an asymmetrical inclined structure, resulting in better sealing of the coin cell.

[0045] Referring to Figures 5 and 6, the value L1 of the distance between the end of the first inclined surface 153 near the first substrate 11 and the first annular wall 13 ranges from 0.18 mm to 0.23 mm. In some embodiments, the value α2 of the angle between the first inclined surface 153 and the plane containing the second substrate 31 ranges from 20° to 40°. This effectively distributes the pressure on the first housing assembly 10 during assembly, reduces the pressure on the first substrate 11, increases the compression ratio of the seal, and improves the sealing performance. It is easily understood that when the first top surface 156 is a horizontal plane, L1 is the length of the first top surface 156. In some other embodiments, the value α2 of the angle between the first inclined surface 153 and the plane containing the second substrate 31 can be 30° or 45°.

[0046] In some specific embodiments, referring to Figure 7, the first end 1541 further includes a first top surface 156, and a first inclined surface 153 adjacent to the first annular wall 13. The first top surface 156 is connected to the end of the first inclined surface 153 away from the first annular wall. That is, the difference between this embodiment and the previous specific embodiment is that in this embodiment, the first inclined surface 153 is located between the first annular wall 13 and the first top surface 156, and the first inclined surface 153 is located inside the first end 1541, that is, on the side closer to the first annular wall 13. The first inclined surface is inclined from the first top surface toward the first annular wall and toward the second substrate.

[0047] In some embodiments, referring to Figures 3, 5, and 7, the end of the seal 15 facing away from the first substrate 11 has a second inclined surface 151 and a second top surface 158. The second top surface 158 is configured to abut against the second substrate 31. The second inclined surface 151 is connected to the end of the second top surface facing away from the first annular wall 13, and is inclined from the second top surface toward the second annular wall and toward the first substrate 11. When the second housing 30 is assembled onto the first housing assembly 10, it can be assembled by stamping. The second inclined surface 151 can guide the second housing 30, so that the second housing 30 can be assembled onto the first housing assembly 10 more smoothly and accurately.

[0048] In some embodiments, referring to Figures 5 and 6, the first inclined surface 153 includes a first end 1511 near the first substrate 11 and a second end 1513 near the first inclined surface of the second substrate 31. The distance between the first end 1511 and the second end 1513 of the first inclined surface is B1 in the horizontal direction, and the distance between the first end 1511 and the second end 1513 of the first inclined surface is B2 in the vertical direction. The ratio of B1 to B2 is greater than or equal to 0.5, and the ratio of B1 to B2 is less than or equal to 2.5. For example, the ratio of B1 to B2 can be 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, or 2.5. Specifically, the ratio of B1 to B2 can be from 0.5 to 1.5, for example: the ratio of B1 to B2 can be 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5. This reduces assembly difficulty and improves manufacturing feasibility and assembly efficiency.

[0049] In some embodiments, the seal can be a sealing ring, with a first bevel circumferentially disposed around the sealing ring. Thus, the bevels around the sealing ring can guide the second housing 30, resulting in better guiding performance.

[0050] In some embodiments, referring to Figures 2 and 5, the button cell also includes a negative electrode 60, a positive electrode 70, and a separator 80 disposed in the receiving cavity 12. The negative electrode 60 is disposed near the first substrate 11, the positive electrode 70 is disposed near the second substrate 31, and the separator 80 is disposed between the positive electrode 70 and the negative electrode 60.

[0051] A first housing assembly 10 can be integrally formed by processing the first substrate 11, the first annular wall 13, and the sealing element 15. The sealing element 15 can be injection molded onto the first substrate 11 and the first annular wall 13. During assembly, the negative electrode 60 needs to be placed in the receiving cavity 12, and the separator 80 and the positive electrode 70 are placed sequentially on the side of the negative electrode away from the first substrate 11. Thus, the separator 80 is located between the negative electrode 60 and the positive electrode 70, which serves to isolate the negative electrode 60 and the positive electrode 70. After that, electrolyte needs to be injected, and the second housing 30 is placed on the first housing assembly 10. Finally, it is sealed to form a coin cell battery. After assembly, the coin cell battery needs to undergo pre-discharge aging.

[0052] In some embodiments, referring to Figure 6, the first substrate 11, the first annular wall 13, and the seal 15 are integrally formed. To improve the sealing effect, in some embodiments, the seal 15, the first substrate 11, and the first annular wall 13 are manufactured by injection molding. The mold structure required for injection molding can adopt a specific angle surface structure design to ensure that the outer side of the formed first housing assembly, i.e., the seal 15, forms an asymmetrical planar structure with a specific angle between it and the top horizontal plane.

[0053] In these embodiments, the first substrate 11, the first annular wall 13, and the seal 15 can be configured as a single-piece structure. In this case, the first substrate 11, the first annular wall 13, and the seal 15 deform together under stress, making it less likely for gaps to form between them. Furthermore, this reduces the assembly steps between the seal 15 and the first housing assembly 10 and improves the sealing performance between the seal 15 and the first housing assembly 10, thereby increasing production efficiency. The single-piece seal 15 provides better sealing between itself and the first substrate 11 and the first annular wall 13.

[0054] In some embodiments, the material of the seal 15 is one of polypropylene and polytetrafluoroethylene.

[0055] Referring to Figure 4, for ease of description, let the average thickness of the plate of the second housing 30 be T. In some embodiments, since the second substrate 31 and the second annular wall 33 are formed by stamping or other methods from a single plate, the average thickness of the plate of the second substrate 31 can be T.

[0056] The shortest distance between the first annular wall 13 and the second annular wall 33 (i.e., the shortest distance of the sidewall gap) is G2, the average thickness of the second substrate 31 is T, and the ratio of G2 to T is 60%-200%. For example, the ratio of G2 to T can be 60%, 70%, 80%, 90%, 100%, 110%, 120%, 130%, 140%, 150%, 160%, 170%, 180%, 190%, or 200%.

[0057] The shortest distance between the first annular wall 13 and the second substrate 31 (i.e., the shortest bottom gap distance) is G3, the average thickness of the second substrate 31 is T, and the ratio of G3 to T is 340%-560%. For example, the ratio of G3 to T can be 340%, 360%, 380%, 400%, 420%, 440%, 460%, 480%, 500%, 520%, 540%, or 560%.

[0058] The shortest distance G1 between the openings of the first housing assembly 10 and the second housing 30 of the button cell is 80%-120% of the average thickness T of the plate material of the second housing.

[0059] Referring to Figure 4, the range of the shortest distance G1 between the opening of the first housing assembly 10 and the second housing 30 of the button cell can be 0.2mm to 0.35mm, specifically 0.2mm, 0.23mm, 0.25mm, 0.3mm, and 0.35mm.

[0060] Referring to Figure 4, the minimum distance G2 value of the sidewall gap can range from 0.15mm to 0.45mm, specifically: 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm; the minimum distance G3 value of the bottom gap can range from 0.85mm to 1.3mm, specifically: 0.85mm, 0.9mm, 0.95mm, 1.0mm, 1.05mm, 1.1mm, 1.25mm, 1.3mm.

[0061] Referring to Figure 4, the radius of curvature R after the second shell 30 is sealed can range from 0.8mm to 1.2mm, specifically from 0.9mm to 1.1mm, and can be 0.9mm, 0.95mm, 1.0mm, 1.05mm, and 1.1mm.

[0062] Referring to Figures 4 and 6, the side wall height dimension H3 of the seal 15 is 100%-106% of the average height H0 of the finished battery cell. The side wall height dimension H3 of the seal 15 mentioned here is the height of the seal 15 when it is in an uncompressed state, that is, in the unfolded state. In this way, the first housing assembly 10 and the second housing 30 can fit more tightly after assembly, which can effectively prevent electrolyte evaporation and external moisture intrusion, and improve the sealing performance of the battery cell.

[0063] In this embodiment, by providing a first inclined surface, the horizontal compressive force can be effectively reduced, thereby reducing the horizontal force on the first substrate 11 in the first housing assembly 10 and concentrating the vertical force, thus preventing bending. The first inclined surface may include an outer inclined surface. To improve the sealing effect, the angle α2 between the first inclined surface 153 and the plane containing the second substrate 31 is 30°.

[0064] Specifically, the material of the seal 15 can be polypropylene PP8830, the shortest distance between the opening of the first housing assembly 10 and the second housing 30 of the button cell is G1=0.23mm, the shortest distance between the side walls is G2=0.30mm, the shortest distance between the bottom is G3=1.2mm, the R=1.1mm after the second housing 30 is sealed, and the angle a2 of the outer bevel at the top of the seal 15 is 30°.

[0065] Experiments have shown that when a2 is 30°, electrolyte evaporation can be reduced, thereby improving battery sealing. Furthermore, it can effectively prevent poor internal contact caused by steel shell bulging in high-temperature environments, thus making the battery characteristics less prone to deterioration and resulting in higher battery electrical performance stability.

[0066] Button cells, also known as coin cells, are generally larger in diameter and thinner. A button cell typically includes a positive terminal cap and a negative terminal cap. Assembling a button cell involves attaching the positive terminal cap to the negative terminal cap and sealing the battery. When installing the positive terminal cap onto the negative terminal cap, it needs to be pressed down towards the negative terminal cap, subjecting the negative terminal cap and sealing ring to significant assembly pressure. Excessive assembly pressure can cause the negative terminal cap to bend, affecting battery performance and lifespan.

[0067] The stamping and forming forces generated during the sealing process subject the negative electrode cap to significant impact. This can lead to deformation of the negative electrode cap, potentially creating gaps between the negative electrode cap and the sealing ring, and between the negative electrode cap and the positive electrode cap, both affecting the cell's sealing performance. Specifically, the battery sealing process includes a stamping process and a sealing process. The stamping process involves placing the combination of the negative and positive electrode caps in a sealing mold and forming the cell through mechanical stamping. During sealing, the mechanical stamping generates stamping force, which is transmitted to the negative electrode cap, causing it to be subjected to the stamping force of the sealing mold. The sealing process involves installing the positive electrode cap on top of the negative electrode cap, sealing the mold, and narrowing the ends of both the positive and negative electrode caps. In the sealing process, the mold applies pressure to the ends of the negative electrode cap to narrow them, resulting in the negative electrode cap being subjected to the forming force of the mold. During the sealing process of button cells, the end of the positive electrode cap facing the negative electrode cap needs to be narrowed, which causes the positive electrode cap to bend and deform inside the mold. The rubber ring deforms along with the positive electrode cap and squeezes the negative electrode cap, putting great pressure on the ring wall of the negative electrode cap. The negative electrode cap is prone to deformation, resulting in gaps between the negative electrode cap and the sealing ring and between the positive electrode cap, and between the negative electrode cap and the sealing ring, which affects the sealing performance of the button cell.

[0068] Firstly, in this embodiment, a first inclined surface 153 is provided on the side of the sealing member 15 facing the first substrate 11. The first inclined surface 153 can disperse assembly pressure during the battery sealing process, resulting in less impact force during assembly. This prevents bending of the first substrate 11 of the first housing assembly 10. Simultaneously, the presence of the first inclined surface 153 improves the compression ratio and uniformity of the sealing member 15, thereby achieving a good sealing effect, ensuring the sealing performance of the coin cell, suppressing electrolyte evaporation in the coin cell, and improving battery performance and lifespan.

[0069] Secondly, based on the first aspect of the solution, the circumferential ring of the seal is provided with a first inclined surface 153. This ensures that the inner side of the second housing 30 continuously and tightly fits the first housing assembly 10, preventing misalignment during assembly and guaranteeing positional accuracy.

[0070] Thirdly, the first substrate 11, the first annular wall 13, and the sealing element 15 are integrally formed. In this embodiment, the first housing assembly 10 includes the first substrate 11, the first annular wall 13, and the sealing element 15. Since the first substrate 11, the first annular wall 13, and the sealing element 15 are integrally formed, they deform together under stress, making it less likely for gaps to form between the first annular wall 13 and the sealing ring. Furthermore, this reduces the assembly steps of the first substrate 11, the first annular wall 13, and the sealing element 15, improves their sealing performance, and thus increases production efficiency.

[0071] Fourth aspect: In this embodiment of the application, a second inclined surface 151 is provided at the end of the sealing member away from the first substrate 11. The second inclined surface 151 has a guiding function, which can guide the second housing 30, so that the second housing 30 and the first housing assembly 10 are assembled smoothly and accurately.

[0072] Fifthly: The first substrate 11, the first annular wall 13, and the seal 15 are integrally formed, with a first inclined surface provided on the seal 15. During the assembly of the second housing 30 and the first housing assembly 10, the first inclined surface can disperse the assembly pressure during battery sealing, preventing bending of the first substrate 11 of the first housing assembly 10, improving the compression ratio and balance of the seal 15 between the seal 15 and the second housing 30, suppressing electrolyte evaporation, and ensuring the sealing performance of the coin cell battery.

Claims

1. A button cell, comprising: a first shell assembly (10) comprising a first base plate (11), a first ring wall (13) and a sealing member (15), the first ring wall (13) being annularly arranged at the periphery of the first base plate (11) and forming a receiving cavity (12) with the first base plate (11), the sealing member (15) being at least partially located on the side of the first ring wall (13) away from the receiving cavity (12); a second shell (30) comprising a second base plate (31) and a second ring wall (33), the second ring wall (33) being connected to the periphery of the second base plate (31), the second ring wall (33) comprising a lap end (331) extending away from the second base plate (31) and configured to form a sealing structure with the sealing member (15) and the first ring wall (13); wherein the sealing member (15) comprises a first end (1541), the first end (1541) being located on the side of the first ring wall (13) away from the receiving cavity (12) and being arranged close to the first base plate (11), the first end (1541) being provided with a first inclined surface (153), the first inclined surface (153) being arranged obliquely relative to the first ring wall (13), and the lap end (331) abutting against the first inclined surface (153). 2.The button cell according to claim 1, the first end (1541) further comprising a first top surface (156), the first top surface (156) being adjacent to the first ring wall (13), the first inclined surface (153) being connected to one end of the first top surface (156) away from the first ring wall (13) and being arranged obliquely away from the first ring wall (13) and the first base plate (11), and the first inclined surface (153) being in contact with the second ring wall (33).

3. The button cell of claim 2, wherein, an angle between the first inclined surface (153) and a plane in which the first ring wall (13) is located is a1, an angle between the first inclined surface (153) and a plane in which the second base plate (31) is located is a2, and a1 is different from a2.

4. The button cell of claim 3, wherein, a distance between one end of the first inclined surface (153) close to the first base plate (11) and the first ring wall (13) is L1, and a value of L1 is in a range of 0.18mm to 0.23mm, and a value of a2 is in a range of 20° to 40°. 5.The button cell according to claim 1, the first end (1541) further comprising a first top surface (156), the first inclined surface (153) being adjacent to the first ring wall (13), and the first top surface (156) being connected to one end of the first inclined surface (153) away from the first ring wall (13), and the first inclined surface (153) being arranged obliquely from the first top surface (156) toward the first ring wall (13) and the second base plate (31).

6. The button cell of any one of claims 1-5, wherein, An end of the sealing member (15) away from the first substrate (11) is provided with a second inclined surface (151) and a second top surface (158), the second top surface (158) is arranged to abut the second substrate (31), the second inclined surface (151) is connected with the second top surface (158) away from one end of the second ring wall (33), and is arranged to be inclined from the second top surface (158) towards the second ring wall (33) and the first substrate (11).

7. The button cell of claim 6, wherein, The first inclined surface (153) comprises a first end (1511) of the first inclined surface and a second end (1513) of the first inclined surface, the first end (1511) of the first inclined surface is close to the first substrate (11), the second end (1513) of the first inclined surface is close to the second substrate (31), in the horizontal direction, the distance between the first end (1511) of the first inclined surface and the second end (1513) of the first inclined surface is B1, in the vertical direction, the distance between the first end (1511) of the first inclined surface and the second end (1513) of the first inclined surface is B2, the ratio of B1 to B2 is greater than or equal to 0.5, and the ratio of B1 to B2 is less than or equal to 2.

5.

8. The button cell of any one of claims 1-5, wherein, The sealing member (15) is a sealing ring, and the first inclined surface (153) is arranged around the sealing ring.

9. The button cell of any one of claims 1-5, wherein, The sealing member (15) is injection molded on the first substrate (11) and the first ring wall (13).

10. The button cell according to any one of claims 1-5, further comprising a negative electrode (60), a positive electrode (70) and a separator (80) arranged in the accommodation cavity (12), the negative electrode (60) is arranged close to the first substrate (11), the positive electrode (70) is arranged close to the second substrate (31), and the separator (80) is arranged between the positive electrode (70) and the negative electrode (60).

11. The button cell of any one of claims 1-5, wherein, The material of the sealing member (15) is one of polypropylene and polytetrafluoroethylene.

12. The button cell of any one of claims 1-5, wherein, The minimum distance between the first ring wall (13) and the second ring wall (33) is G2, the average thickness of the second substrate (31) is T, and the ratio of G2 to T is 60%-200%.

13. The button cell of any one of claims 1-5, wherein, The minimum distance between the first ring wall (13) and the second substrate (31) is G3, the average thickness of the second substrate (31) is T, and the ratio of G3 to T is 340%-560%.

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