Button cell and electric device

Abstract

The application discloses a button cell and an electric device. The button cell comprises a positive shell, a negative shell and a sealing member. The part of the side wall of the positive shell at the opening end converges radially to form a bending part. The negative shell is arranged opposite to the positive shell and partially extends into the positive shell. The bending part buckles the sealing member on the negative shell. The sealing member is connected to the positive shell and the negative shell in a sealing mode. In the axial direction of the button cell, the sealing member extends between the opening end and the upper surface of the negative shell. The size of the sealing member extending out of the opening end is H. The thickness of the sealing member between the part of the side wall of the positive shell at the bottom and the side surface of the negative shell is defined as D. 0.4D≤H<2.0D. The application takes into account the sealing performance of the battery, the electrical performance of the battery and the integrity of the appearance structure.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more particularly to a button cell battery and an electrical device. Background Technology

[0002] Button batteries, also known as coin batteries or coin batteries, are a type of miniature battery with a flat, round shape and a small size.

[0003] The button cell includes a positive electrode shell, a negative electrode shell, a sealing sleeve, and an electrode assembly. The upper end of the positive electrode shell has a contraction opening to clamp and fix the sealing sleeve between the positive electrode shell and the negative electrode shell, so that the positive electrode shell and the negative electrode shell enclose a sealed space, and the electrode assembly is installed in the sealed space.

[0004] In related technologies, there is direct contact between the positive and negative casings, which can lead to short circuits and affect the reliability of the battery. Summary of the Invention

[0005] This application provides a button cell battery and an electrical device that improves the electrical insulation performance of the button cell battery, thereby at least partially solving the above-mentioned technical problems.

[0006] To achieve the above objectives, according to a first aspect of this application, a button cell battery is provided, comprising: The positive casing, wherein a portion of the sidewall of the positive casing at the open end converges radially along the button cell to form a curved portion; A negative housing is disposed opposite to the positive housing, and a portion of the negative housing extends into the positive housing; A sealing element, wherein the curved portion presses the sealing element onto the negative housing, the sealing element sealingly connecting the positive housing and the negative housing, and extending along the axial direction of the button cell to between the opening end and the upper surface of the negative housing; Wherein, the dimension of the seal extending from the opening end is H, and the thickness of the seal between the bottom portion of the positive housing and the side of the negative housing is defined as D, where 0.4D≤H<2.0D.

[0007] Optionally, 0.5D ≤ H ≤ 1.6D. This forms a reliable insulating barrier, effectively isolating electrical contact paths and significantly reducing the risk of battery short circuits.

[0008] Optionally, H=0.8D. This avoids situations where the seal extends too far beyond the opening, affecting aesthetics, etc.

[0009] Optionally, 0.1mm ≤ D ≤ 1mm. The seal is not easily damaged during assembly and encapsulation and can withstand the minute pressures that may be generated inside the battery over a long period of time.

[0010] Optionally, the seal has a groove on one side facing the positive housing, and the groove is filled with a sealing medium. This forms a double seal, improving the sealing performance of the button cell.

[0011] Optionally, the bottom wall of the seal is located between the end of the negative housing and the bottom of the positive housing, and the bottom wall of the seal is provided with the groove. This effectively improves the sealing performance between the positive housing and the seal.

[0012] Optionally, the depth of the groove is set to H1, and the wall thickness of the bottom wall of the seal is H2; wherein 1 / 8 ≤ H1 / H2 ≤ 1 / 3; and / or, 0.3mm ≤ H2 ≤ 1.0mm; and / or, 0.03mm ≤ H1 ≤ 0.33mm. This ensures that sufficient sealing medium is filled into the groove while maintaining the structural strength of the bottom wall of the seal.

[0013] Optionally, along the radial direction of the button cell, the width of the groove opening is D1, and the width of the bottom wall of the seal is set to D2; wherein 1 / 4 ≤ D1 / D2 ≤ 1 / 2; and / or, 0.5mm ≤ D2 ≤ 2.0mm; and / or, 0.12mm ≤ D1 ≤ 0.67mm. This facilitates the filling of the groove with a sealing medium, while maximizing the amount of sealing medium filling the groove, thereby enhancing the sealing performance of the button cell.

[0014] Optionally, the negative housing includes a top cover, a bent portion, and a folded-back portion. The bent portion is arranged circumferentially along the top cover and connects the top cover and the folded-back portion. The folded-back portion folds back from the end of the bent portion away from the top cover and extends towards the top cover, fitting against the outer side of the bent portion. The distance between the center line of the distance between the two opposite sides of the folded-back portion and the bent portion and the central axis of the groove is t, where 0 ≤ t ≤ 0.05 mm. This reduces the probability of uneven sealing due to excessive or insufficient pressure on a certain part of the seal, thus improving the sealing effect of the seal.

[0015] According to a second aspect of this application, an electrical device is provided, comprising a button battery as described in any of the preceding claims.

[0016] The coin cell battery and electrical device of this application embodiment form a reliable insulating barrier between the positive and negative casings by pressing the seal against the seal, thereby effectively isolating the electrical contact path and significantly reducing the potential risk of short circuits in the coin cell battery. If H is less than 0.4D, an electrolyte residue area will form at the contact surface between the seal and the positive casing, causing continuous corrosion of the metal interface by the electrolyte, affecting the battery's safety performance and appearance. If H is greater than 2.0D, the seal will be excessively extruded (burrs), affecting the battery's appearance and structural integrity, and impacting the actual performance of the cell. The size of the seal extending beyond the opening of the positive casing balances the battery's sealing performance, electrical performance, and structural integrity.

[0017] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0019] Figure 1 This is a cross-sectional view of a button cell provided in an exemplary embodiment of this disclosure; Figure 2 This is a partially enlarged schematic diagram of a button cell provided in an exemplary embodiment of this disclosure; Figure 3 This is a cross-sectional view of a button cell with a groove provided in an exemplary embodiment of this disclosure; Figure 4 This is a partially enlarged schematic diagram of a button cell with a groove provided in an exemplary embodiment of this disclosure; Figure 5 This is a schematic diagram illustrating the labeling of a button cell provided in an exemplary embodiment of this disclosure; Figure 6 This is a schematic diagram of an electrical device provided in an exemplary embodiment of this disclosure.

[0020] Explanation of reference numerals in the attached figures: 10. Electrical equipment; 100. Button cell battery; 110. Main body; 111. Bent portion; 112. First support surface; 113. Second support surface; 114. Vertical section; 115. Open end; 120. Negative shell; 121. Top cover; 122. Bending section; 123. First sub-section; 124. Second sub-section; 125. Third sub-section; 126. Fold-back section; 130. Seal; 131. Slot; 132. First sealing section; 133. Second sealing section; 134. Third sealing section; 135. Sealing groove; 136. Groove; 140. Electrode assembly; 141. Negative current collector; 142. Negative electrode sheet; 143. Separator; 144. Positive electrode sheet; 145. Positive current collector. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0022] See Figure 1 This application provides a button cell battery 100, including a positive casing 110, a negative casing 120, a sealing member 130, and an electrode assembly 140. The negative casing 120 is disposed opposite to the positive casing 110, and a portion of the negative casing extends into the positive casing 110. The negative casing 120 and the positive casing 110 enclose a receiving space. The electrode assembly 140 is installed within the receiving space.

[0023] The housing 110 includes a connected bottom and a sidewall, with the sidewall connected around the bottom. A bend 111 is formed on the sidewall of the housing 110 near the opening end 115. The bend 111 converges radially along the button cell 100, forming a constricted structure on the housing 110.

[0024] The negative housing 120 extends from the opening end 115 into the positive housing 110. A seal 130 is sealingly connected between the positive housing 110 and the negative housing 120. A bend 111 crimps the seal 130, sealingly connecting the negative housing 120 and the positive housing 110. The bend 111 acts on the negative housing 120 through a crimping process, fixing the seal 130 in the gap between the positive housing 110 and the negative housing 120 by this crimping force, with the end of the seal 130 being extruded outside the positive housing 110. Along the axial direction of the button cell 100, the seal 130 extends between the opening end 115 and the upper surface of the negative housing 120. The dimension of the seal 130 extending beyond the opening end 115 is H, and the thickness of the seal 130 between the bottom portion of the sidewall of the positive housing 110 and the side of the negative housing 120 is defined as D, where 0.4D ≤ H < 2.0D. The value of H can be 0.4D, 0.6D, 0.7D, 0.9D, 1.1D, 1.2D, 1.5D, 1.7D, 1.8D, 1.9D, 2.0D or other unlisted values.

[0025] In this embodiment, the seal 130 is compressed by the positive housing 110 and the negative housing 120, forming a reliable insulating barrier between them. This effectively isolates the electrical contact path and significantly reduces the potential risk of a short circuit in the coin cell 100. If H is less than 0.4D, an electrolyte residue area will form at the contact surface between the seal 130 and the positive housing 110, causing continuous corrosion of the metal interface by the electrolyte and affecting the battery's safety performance and appearance. If H is greater than 2.0D, the seal 130 will be excessively extruded (burrs), affecting the battery's appearance and structural integrity, and impacting the actual performance of the cell.

[0026] See in some examples Figure 1 and Figure 2 The button cell 100 includes a positive housing 110, a negative housing 120, a seal 130, and an electrode assembly 140. The negative housing 120 is inverted inside the positive housing 110, and the seal 130 is sealed between the positive housing 110 and the negative housing 120 to form a sealed space. The electrode assembly 140 is installed in the sealed space.

[0027] The electrode assembly 140 includes a negative current collector 141, a negative electrode plate 142, a separator 143, a positive electrode plate 144, and a positive current collector 145 stacked sequentially from the top of the negative housing 120 to the bottom of the positive housing 110. The separator 143 separates the negative electrode plate 142 and the positive electrode plate 144. Electrolyte fills the sealed space, immersing the electrode assembly 140 in the electrolyte.

[0028] The positive housing 110 includes a bottom and sidewalls, the sidewalls being connected to the perimeter of the bottom and extending toward the negative housing 120. The sidewalls of the positive housing 110 include a curved portion 111 near the opening end 115 and a vertical section 114 connecting the curved portion 111 and the bottom.

[0029] The negative housing 120 includes a top cover portion 121, a bent portion 122, and a folded-back portion 126. The bent portion 122 is disposed circumferentially along the top cover portion 121 and extends outward and downward. The bent portion 122 connects the top cover portion 121 and the folded-back portion 126. The folded-back portion 126 extends from one end of the bent portion 122 away from the top cover portion 121 toward the top cover portion 121 and fits against the outer surface portion of the bent portion 122. Along the radial direction of the button cell 100, the open end 115 of the bent portion 111 extends between the two ends of the bent portion 122. The bending portion 122 includes a first sub-portion 123, a second sub-portion 124, and a third sub-portion 125. The first sub-portion 123 extends from the periphery of the top cover portion 121 along a direction forming an angle with the axis of the button cell 100. The second sub-portion 124 smoothly connects the first sub-portion 123 and the third sub-portion 125. The second sub-portion 124 extends from the end of the first sub-portion 123 away from the top cover portion 121 in a direction away from the top cover portion 121. The third sub-portion 125 extends from the end of the second sub-portion 124 away from the first sub-portion 123 along the axial direction of the button cell 100 toward the side where the housing 110 is located. The folded portion 126 extends from the side of the third sub-portion 125 away from the second sub-portion 124 along the axial direction of the button cell 100 toward the side where the top cover portion 121 is located, and the folded portion fits against the outer side wall of the third sub-portion 125. The end of the bending portion 111 extends between the two ends of the second sub-portion 124.

[0030] The seal 130 includes a first sealing section 132, a second sealing section 133, and a third sealing section 134 connected in sequence, which together form a sealing groove 135. The connection between the bent portion 122 and the folded-back portion 126 of the negative housing 120 is located within the sealing groove 135 and is sealed to the groove wall of the sealing groove 135. The first sealing section 132 is located between the side wall of the positive housing 110 and the negative housing 120. One side of the first sealing section 132 is in contact with the inner surface of the side wall of the positive housing 110, and the other side of the first sealing section 132 is in contact with the outer surface of the folded-back portion 126 of the negative housing 120 and a portion of the outer surface of the bent portion 122 located above the folded-back portion 126. The end of the first sealing section 132 away from the second sealing section 133 extends out of the opening end 115 of the positive housing 110. Along the axial direction of the button cell 100, the first sealing section 132 extends outward to the opening end 115 with a dimension of H. The thickness of the first sealing section 132 between the vertical section 114 and the folded-back portion 126 of the positive housing 110 is defined as D, where 0.4D ≤ H < 2.0D. The second sealing section 133 is connected to the end of the first sealing section 132 away from the opening end 115, and the second sealing section 133 is attached to the bottom inner surface of the positive housing 110. The third sealing section 134 extends from the second sealing section 133 toward the negative housing 120, and a groove 131 is formed between the third sealing section 134 and the bend portion 122 to receive and fix the end of the separator 143.

[0031] In some embodiments, 0.5D ≤ H ≤ 1.6D. The value of H can be 0.5D, 1.0D, 1.3D, 1.6D, or other unlisted values. The preferred range of H is 0.5D to 1.6D, which ensures that during the encapsulation process, the seal 130 has more material to participate in the deformation, forming a reliable insulating barrier, thereby effectively isolating the electrical contact path and significantly reducing the risk of battery short circuit.

[0032] In some embodiments, H=0.8D. This provides sufficient material to form a high-quality seal and reliable insulation performance, while reducing the probability of issues such as the seal 130 extending too far beyond the opening end 115, affecting aesthetics.

[0033] In some embodiments, 0.1mm ≤ D ≤ 1mm. The value of D can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm or other unlisted values.

[0034] In this embodiment, the value of D is ≥0.1mm to ensure that the seal 130 has sufficient body strength, is not easily damaged during assembly and packaging, and can withstand the minor pressure that may be generated inside the battery over a long period of time. Controlling the value of D is crucial within the limited space of the coin cell 100 (especially its height). An upper limit of 1mm ensures that the electrode assembly 140 has maximum space, thereby guaranteeing the battery's capacity and energy density.

[0035] In some embodiments, see Figure 3 and Figure 4 The sealing element 130 has a groove 136 on one side facing the housing 110, and the groove 136 is filled with a sealing medium. The material of the sealing medium includes one or more of styrene-butadiene rubber, epoxy resin, silicone rubber, fluororubber, phenolic resin, and polyimide.

[0036] By filling the groove 136 of the seal 130 with a sealing medium, when the positive housing 110, negative housing 120, and seal 130 undergo micro-deformation due to stress or temperature changes, creating gaps, the sealing medium deforms accordingly to fill the gaps. This allows the seal 130 to effectively prevent moisture penetration from the outside of the coin cell 100 and also effectively inhibit electrolyte leakage from the inside of the coin cell 100, thereby enhancing the sealing performance of the coin cell 100. The seal 130 and the sealing medium form a double seal, improving the sealing performance of the coin cell 100.

[0037] In some examples, the material of the seal 130 includes, but is not limited to, one or more of polyphenylene sulfide (PPS) or polyethylene terephthalate (PET), liquid crystal polymer (LCP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin (PFA), polyether ether ketone resin (PEEK), polyether nitrile resin (PEN), polyether ketone resin (PEK), polyacrylate resin, polybutylene terephthalate resin (PBT), and polyether sulfone resin (PES), enabling the seal 130 to withstand high temperatures greater than 280°C.

[0038] In some embodiments, see Figure 3 and Figure 4 The bottom wall of the seal 130 is located between the end of the side wall of the negative housing 120 and the bottom of the positive housing 110, and the bottom wall of the seal 130 is provided with a groove 136.

[0039] See some sub-examples. Figure 3 and Figure 4 The second sealing section 133 has a groove 136 on one side of the housing 110 facing the bottom.

[0040] In this embodiment, a groove 136 is provided on the side of the second sealing section 133 facing the bottom of the housing 110. The sealing medium in the groove 136 is also in contact with the bottom of the housing 110, so that the sealing medium can effectively improve the sealing performance between the housing 110 and the seal 130.

[0041] In some other examples, a groove 136 is provided on the side of the seal 130 facing the sidewall of the housing 110. For example, the groove 136 is provided on the side of the first sealing segment 132 away from the folded-back segment.

[0042] In some embodiments, see Figure 5 The depth of the groove 136 is set to H1, and the wall thickness of the bottom wall of the seal 130 is H2, where 1 / 8 ≤ H1 / H2 ≤ 1 / 3. This ensures that sufficient sealing medium is filled into the groove 136 while maintaining the structural strength of the bottom wall of the seal 130. The wall thickness of the bottom wall of the seal 130 can be understood as the wall thickness of the portion of the second sealing section 133 outside the groove 136. The value range of H1 / H2 can be 1 / 8, 1 / 6, 1 / 5, 1 / 4, 1 / 3, or any two of these values, or a range between any two of these values, such as 1 / 6 to 1 / 4.

[0043] Understandably, when the ratio between the depth of the groove 136 and the wall thickness H2 of the bottom wall of the seal 130 is less than 1 / 8, the depth H1 of the groove 136 is shallower, and the amount of sealing medium is less, meaning the amount of sealing medium occupies less than 30% of the space where the bottom wall of the seal 130 is located. This makes it difficult to effectively prevent external moisture from entering the coin cell 100, and provides virtually no benefit to the sealing performance of the coin cell 100. Conversely, when the ratio between the depth of the groove 136 and the wall thickness of the bottom wall of the seal 130 is greater than 1 / 3, the depth of the groove 136 is greater, which significantly weakens the structural strength of the bottom wall of the seal 130. Furthermore, during the sealing process of the coin cell 100, the sealing pressure may cause the bottom wall of the seal 130 to break or penetrate, leading to leakage of the coin cell 100 and increasing the defect rate in production.

[0044] In some embodiments, 0.3mm ≤ H2 ≤ 1.0mm. The wall thickness H2 of the bottom wall of the seal 130 can be 0.3mm, 0.5mm, 0.6mm, 0.8mm, 1.0mm, or any value between any two of the above, or a range between any two of the above values.

[0045] In some embodiments, 0.03mm ≤ H1 ≤ 0.33mm. The depth H1 of the groove 136 on the bottom wall of the seal 130 can be 0.03mm, 0.05mm, 0.07mm, 0.09mm, 0.10mm, 0.11mm, 0.12mm, 0.15mm, 0.18mm, 0.2mm, 0.23mm, 0.25mm, 0.28mm, 0.30mm, 0.33mm, or any value between any two of the above values, or a range between any two of the above values. These values ​​are not listed one by one in the embodiments of this application.

[0046] The wall thickness H2 of the bottom wall of the seal 130 ranges from 0.3mm to 1.0mm, and the depth H1 of the groove 136 on the bottom wall of the seal 130 ranges from 0.03mm to 0.33mm, so that sufficient sealing medium can be filled in the groove 136 while maintaining the structural strength of the bottom wall of the seal 130.

[0047] In some embodiments, see Figure 5 The width of the groove 136 of the sealing element 130 is set to D1, and the width of the bottom wall of the sealing element 130 is set to D2, where 1 / 4 ≤ D1 / D2 ≤ 1 / 2. This allows the groove 136 of the sealing element 130 to have a larger opening, facilitating the filling of the sealing medium within the groove 136 and effectively increasing the amount of sealing medium filling the groove 136, thereby enhancing the sealing performance of the button cell battery 100. When the ratio between the width D1 of the groove 136 of the sealing element 130 and the width D2 of the bottom wall of the sealing element 130 is less than 1 / 4, with the width D2 of the bottom wall of the sealing element 130 remaining unchanged, the width D1 of the groove 136 is smaller, making it difficult to coat the inside of the groove 136 with sealing medium. Simultaneously, the amount of sealing medium filling the inside of the groove 136 is less, making it difficult to effectively prevent external moisture from entering the button cell battery 100, thus offering virtually no benefit to the sealing performance of the button cell battery 100. Furthermore, when the ratio between the width D1 of the groove 136 of the seal 130 and the width D2 of the bottom wall of the seal 130 is set to be greater than 1 / 2, under the premise that the width D2 of the bottom wall of the seal 130 remains unchanged, the width D1 of the groove 136 of the seal 130 is larger. This leads to the seal 130 being over-compressed and deformed during assembly, resulting in a larger compression of the bottom wall of the seal 130. This affects the overall height and side height of the button cell 100, and may even cause the button cell 100 to bulge, affecting the electrical performance of the button cell 100.

[0048] See some sub-examples. Figure 5The ratio between the width D1 of the groove 136 of the seal 130 and the width D2 of the bottom wall of the seal 130 can be 1 / 4, 1 / 3, 1 / 2, or any two of the above values, or a range between any two of the above values.

[0049] In some embodiments, see Figure 5 The width D2 of the bottom wall of the seal 130 ranges from 0.5mm to 2.0mm, and the width D1 of the groove 136 on the bottom wall of the seal 130 ranges from 0.12mm to 0.67mm. This allows the groove 136 of the seal 130 to have a larger opening, which facilitates the filling of the sealing medium in the groove 136 and can also effectively increase the filling amount of the sealing medium in the groove 136, thereby enhancing the sealing performance of the button cell 100.

[0050] In some sub-examples, the width D2 of the bottom wall of the seal 130 can be 0.5mm, 0.7mm, 0.9mm, 1.1mm, 1.3mm, 1.5mm, 1.8mm, 2.0mm, or any value between any two of the above, or a range between any two of the above values. The width D1 of the groove 136 on the bottom wall of the seal 130 can be 0.12mm, 0.15mm, 0.18mm, 0.20mm, 0.25mm, 0.30mm, 0.35mm, 0.40mm, 0.45mm, 0.50mm, 0.55mm, 0.60mm, 0.65mm, 0.67mm, or any value between any two of the above, or a range between any two of the above values.

[0051] In some embodiments, see Figure 4 and Figure 5 The negative housing 120 includes a top cover 121, a bent portion 122, and a folded-back portion 126. The bent portion 122 is arranged circumferentially along the top cover 121 and connects the top cover 121 and the folded-back portion 126. The folded-back portion 126 folds back from the end of the bent portion 122 away from the top cover 121 and extends towards the top cover 121, fitting against the outer surface portion of the bent portion 122. The sealing element 130 has a sealing groove 135, and the connecting end of the bent portion 122 and the folded-back portion 126 is located in the sealing groove 135. Along the radial direction of the button cell 100, the distance between the central axis of the groove 136 and the center line of the distance between the two opposite sides of the bent portion 122 and the folded-back portion 126 is t, where 0 ≤ t ≤ 0.05 mm. The value of t can be 0.01mm, 0.02mm, 0.03mm, 0.04mm, 0.05mm or other unlisted values.

[0052] The center line of the distance between the opposite sides of the bent portion 122 and the folded-back portion 126 is basically coaxial with the central axis of the groove 136. When the positive housing 110 and the negative housing 120 are assembled, the force exerted by the negative housing 120 on the seal 130 and the groove 136 is relatively uniform. This reduces the probability of uneven sealing due to excessive or insufficient pressure on a certain part of the seal 130, and improves the sealing effect of the seal 130.

[0053] The second aspect, see [link / reference]. Figure 6 This application also provides an electrical device 10, which includes a button cell battery 100 as described above. The electrical device 10 includes the button cell battery 100 described above, and the electrical device 10 has all the beneficial effects of the button cell battery 100 described above, which will not be repeated here.

[0054] The electrical device 10 in the embodiments of this application can be a smart camera, digital camera, dashcam, sensor, or other devices, and this disclosure does not specifically limit it.

[0055] The technical solutions and effects of this application will be described in detail below through specific embodiments and comparative examples. The following embodiments are only some embodiments of this application and are not intended to limit this application in any specific way.

[0056] The structure of the button cell 100 in test group 1 is as follows: The button cell 100 includes a positive housing 110, a negative housing 120, a seal 130, and an electrode assembly 140. The negative housing 120 is inverted inside the positive housing 110, the seal 130 is sealed between the positive housing 110 and the negative housing 120 to form a sealed space, and the electrode assembly 140 is installed in the sealed space.

[0057] The electrode assembly 140 includes a negative current collector 141, a negative electrode plate 142, a separator 143, a positive electrode plate 144, and a positive current collector 145 stacked sequentially from the top of the negative housing 120 to the bottom of the positive housing 110. The separator 143 separates the negative electrode plate 142 and the positive electrode plate 144. Electrolyte fills the sealed space, immersing the electrode assembly 140 in the electrolyte.

[0058] The positive housing 110 includes a bottom and sidewalls, the sidewalls being connected to the perimeter of the bottom and extending toward the negative housing 120. The sidewalls of the positive housing 110 include a curved portion 111 near the opening end 115 and a vertical section 114 connecting the curved portion 111 and the bottom.

[0059] The negative housing 120 includes a top cover portion 121, a bent portion 122, and a folded-back portion 126. The bent portion 122 is arranged circumferentially along the top cover portion 121 and extends outward and downward. The bent portion 122 connects the top cover portion 121 and the folded-back portion 126. The folded-back portion 126 extends from one end of the bent portion 122 away from the top cover portion 121 toward the top cover portion 121 and fits against the outer surface portion of the bent portion 122. Along the radial direction of the button cell 100, the open end 115 of the bending portion 111 extends to between the two ends of the bent portion 122. The bottom of the positive housing 110 is provided with a first support surface 112 and a second support surface 113. The first support surface 112 is located on the outer periphery of the second support surface 113 and is closer to the negative housing 120 than the second support surface 113.

[0060] The seal 130 includes a first sealing section 132, a second sealing section 133, and a third sealing section 134 connected in sequence, which together form a sealing groove 135. The connection between the bent portion 122 and the folded-back portion 126 of the negative housing 120 is located within the sealing groove 135 and is sealed to the groove wall of the sealing groove 135. The first sealing section 132 is located between the side wall of the positive housing 110 and the negative housing 120. One side of the first sealing section 132 is in contact with the inner surface of the side wall of the positive housing 110, and the other side of the first sealing section 132 is in contact with the outer surface of the folded-back portion 126 of the negative housing 120 and a portion of the outer surface of the bent portion 122 located above the folded-back portion 126. The end of the first sealing section 132 away from the second sealing section 133 extends out of the opening end 115 of the positive housing 110. Along the axial direction of the button cell 100, the first sealing section 132 extends outward to the opening end 115 with a dimension of H. The thickness of the first sealing section 132 between the vertical section 114 and the folded-back portion 126 of the positive housing 110 is defined as D, where 0.4D ≤ H < 2.0D. The second sealing section 133 is connected to the end of the first sealing section 132 away from the opening end 115, and the second sealing section 133 is attached to the bottom inner surface of the positive housing 110. The third sealing section 134 extends from the second sealing section 133 toward the negative housing 120, and a groove 131 is formed between the third sealing section 134 and the bend portion 122 to receive and fix the end of the separator 143.

[0061] The testing method for this test group 1 is as follows: 1. Basic electrical performance of the battery; 2. The assembled button cell 100 was subjected to charge and discharge cycle tests, with the test voltage being 2.0-3.3V and the current being 0.1C.

[0062] Table 1. Comparison of test results between the examples and comparative examples in test group 1.

[0063] As shown in Table 1, when H:D equals 0.2, the button cell battery short-circuits; when H:D equals 2, the button cell battery is too tall. Designing H:D to be 0.4 or higher ensures sufficient sealing material is compressed, reliably separating the positive and negative casings 120, fundamentally eliminating the risk of short circuits caused by insufficient sealing compression, and guaranteeing the battery's basic function and safety. Controlling H:D below 2.0 ensures that the final total height of the button cell 100 meets industry standards and space limitations, guaranteeing the product's assemblability and versatility.

[0064] The structure of the button cell 100 in test group 2 is as follows: based on the structure of the button cell 100 in test group 1, a groove 136 is provided on the bottom wall of the sealing element 130.

[0065] Test method: High-temperature shock test on button cell 100; Test method: Record the initial weight G0 of the button cell 100 before the high temperature impact test and the weight G1 of the button cell 100 after the high temperature impact test. Weight loss rate = (G0-G1) / G0*100, in % units. A weight loss rate of no more than 0.06% is considered qualified.

[0066] Table 2. Comparison of Parameter Designs for Examples and Comparative Examples

[0067] Table 3. Comparison of Test Results for Examples and Comparative Examples

[0068] Analysis of experimental data from five sets of examples and five sets of comparative examples revealed that: As shown in Comparative Example 2, when the ratio H1:H2 between the depth H1 of the groove 136 on the bottom wall of the seal 130 of the button cell 100 and the wall thickness H2 of the bottom wall of the seal 130 is set to be greater than 1 / 3, the seal 130 will break.

[0069] As shown in Comparative Example 1, when the ratio H1:H2 between the depth H1 of the groove 136 on the bottom wall of the seal 130 of the button cell 100 and the wall thickness H2 of the bottom wall of the seal 130 is set to less than 1 / 8, the internal resistance of the button cell 100 increases significantly after high-temperature impact, the weight loss rate is large, the capacity decreases significantly, and leakage occurs.

[0070] As shown in Comparative Example 3, when the ratio D1:D2 between the width D1 of the groove 136 of the seal 130 and the width D2 of the bottom wall of the seal 130 is set to less than 1 / 4, after the high temperature impact, the internal resistance of the button cell 100 increases significantly, the height change increases, the weight loss rate is large, the capacity decreases significantly, and leakage occurs.

[0071] As shown in Comparative Example 4, when the ratio D1:D2 between the width D1 of the groove 136 of the seal 130 and the width D2 of the bottom wall of the seal 130 is set to be greater than 1 / 2, the height change of the button cell 100 increases significantly after high-temperature impact, and the capacity decreases significantly.

[0072] As shown in Comparative Example 5, when the distance deviation t between the central axis of the groove 136 on the bottom wall of the seal 130 extending along the height direction of the button cell 100 and the center line of the distance between the two sides opposite to the folded portion 126 and the bent portion 122 of the negative housing 120 is set to be greater than 0.05 mm, after the high temperature impact, the internal resistance of the button cell 100 increases significantly, the height change increases, the weight loss rate is large, the capacity decreases significantly, and leakage occurs.

[0073] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0074] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0075] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0076] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A button cell battery (100), characterized in that, include: The positive housing (110) has a portion of its sidewall at the open end (115) that converges radially along the button cell (100) to form a curved portion (111). A negative housing (120) is disposed opposite to the positive housing (110), and a portion of the negative housing (120) extends into the positive housing (110); A seal (130) is provided, wherein the bent portion (111) presses the seal (130) onto the negative housing (120), the seal (130) sealingly connecting the positive housing (110) and the negative housing (120), and the seal (130) extends along the axial direction of the button cell (100) to between the opening end (115) and the upper surface of the negative housing (120); Wherein, the dimension of the seal (130) extending out of the opening end (115) is H, and the thickness of the seal (130) between the bottom portion of the sidewall of the positive housing (110) and the side of the negative housing (120) is defined as D, 0.4D≤H<2.0D.

2. The button cell battery (100) according to claim 1, characterized in that, 0.5D≤H≤1.6D.

3. The button cell (100) according to claim 2, characterized in that, H=0.8D.

4. The button cell (100) according to claim 2, characterized in that, 0.1mm≤D≤1mm.

5. The button cell (100) according to any one of claims 1 to 4, characterized in that, The seal (130) has a groove (136) on one side facing the housing (110), and the groove (136) is filled with a sealing medium.

6. The button cell (100) according to claim 5, characterized in that, The bottom wall of the seal (130) is located between the end of the negative housing (120) and the bottom of the positive housing (110), and the bottom wall of the seal (130) is provided with the groove (136).

7. The button cell (100) according to claim 6, characterized in that, The depth of the groove (136) is set to H1, and the wall thickness of the bottom wall of the seal (130) is H2; wherein, 1 / 8 ≤ H1 / H2 ≤ 1 / 3; And / or, 0.3mm≤H2≤1.0mm; And / or, 0.03mm≤H1≤0.33mm.

8. The button cell (100) according to claim 7, characterized in that, Along the radial direction of the button cell (100), the width of the groove (136) is D1, and the width of the bottom wall of the seal (130) is set to D2; wherein, 1 / 4 ≤ D1 / D2 ≤ 1 / 2; And / or, 0.5mm≤D2≤2.0mm; And / or, 0.12mm≤D1≤0.67mm.

9. The button cell (100) according to claim 5, characterized in that, The negative housing (120) includes a top cover (121), a bent portion (122), and a folded-back portion (126). The bent portion (122) is arranged circumferentially along the top cover (121). The bent portion (122) is connected to the top cover (121) and the folded-back portion (126). The folded-back portion (126) is folded back from one end of the bent portion (122) away from the top cover (121) and extends toward the top cover (121), and fits against the outer side of the bent portion (122). The distance between the center line of the distance between the two opposite sides of the folded-back portion (126) and the bending portion (122) and the central axis of the groove (136) is t, where 0≤t≤0.05mm.

10. An electrical appliance (10), characterized in that, Including the button cell (100) as described in any one of claims 1 to 9.

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