A hard seal head device for soft pack button cell

Abstract

The application relates to a hard sealing head device of a soft package button cell, which comprises upper and lower sealing heads, the sealing head comprises a sealing head base, left and right limiting tables, a reinforcing table and a sealing table, the middle of the sealing head base is provided with the sealing table, the left and right sides of the sealing table are provided with lower left and right limiting tables, the inner side of the sealing table is provided with the reinforcing table matched with the shape of the sealing table, the whole lower sealing head structure is formed, the sealing table is arranged along the length direction of the sealing head base, the sealing table comprises a circular sealing area, a linear sealing area and a trapezoidal transition sealing area, the wide-mouth type sealing area is formed, the upper and lower sealing heads are arranged at corresponding positions and have the same structure, the symmetrical upper and lower sealing head structures are formed, the upper and lower limiting tables are in contact, the hard sealing gap is arranged between the upper and lower sealing tables after being buckled, and the reinforcing table is provided with a heat insulation plate. Advantageous effects: the wide-mouth type sealing area is helpful for automatic liquid injection after hole expansion of the equipment, the sealing is symmetrically designed along the two sides of the transverse center line of the sealing head, the sealing head is balanced in stress, and the hole expansion and liquid injection are facilitated.

Description

Technical Field

[0001] This invention belongs to the field of lithium battery production technology, and particularly relates to a hard-sealing device for a soft-pack button cell. Background Technology

[0002] With the development of lithium-ion batteries, the structural types of pouch batteries are also increasing, such as single-pit square pouch batteries, double-pit square pouch batteries, cylindrical pouch batteries, arc-shaped batteries, button batteries, etc. As the structural types of lithium-ion batteries become more diverse, the structure of lithium-ion battery end caps is also changing. Patent document CN 213936308 U discloses a polymer button-type lithium-ion battery end cap device, including an upper end cap and a lower end cap; the lower end cap has a positioning groove and a limiting groove on its side wall opposite to the upper end cap, the limiting groove being located outside the positioning groove, and an adhesive strip is disposed within the limiting groove; the upper end cap has a receiving groove on its side wall opposite to the lower end cap for accommodating the battery. The aforementioned existing technology belongs to the traditional soft packaging structure, which has the following disadvantages: First, the end cap of the soft packaging structure does not have an unsealed front edge area, the tab adhesive is easy to deform, and the silicone strip of the end cap of the soft packaging structure needs to be replaced regularly, resulting in high end cap processing costs and silicone strip material costs; Second, the main body of the battery cell is on one side of the end cap, the upper and lower end caps are subjected to uneven stress, which is easy to deform after long-term use and the end cap has a short service life.

[0003] Patent document CN 215496866U discloses a high-strength soft-pack snap-on battery end cap, comprising an aluminum-plastic film, an aluminum plate, and a rigid end cap. A shallow pit is provided on one side of the upper surface of the aluminum-plastic film, and a deep pit is provided on the upper surface of the aluminum-plastic film behind the shallow pit. An air bladder is provided on the upper surface of the aluminum-plastic film on one side of the shallow pit. A tab groove is formed on the outer side of the aluminum-plastic film, and a sealing edge is provided on the outer side of the shallow pit. A silicone plate is fixedly connected to one side of the aluminum plate, and a fixing groove is formed in the middle of the silicone plate. Tab clearance grooves are formed on the front side of the silicone plate on both sides of the fixing groove. A pressing strip corresponding to the fixing groove is provided on the front side of the rigid end cap, and an opening groove is formed on the front side of the rigid end cap. This structure is a composite layer structure of silicone plate, aluminum plate, and rigid end cap, which is not only relatively complex but also equivalent to a soft-pack end cap structure, sharing the disadvantages of a soft-pack end cap.

[0004] Patent document CN 108630836B discloses a sealing end for a soft-pack disc-shaped polymer lithium-ion battery, including a heat-conducting component and a first end. The heat-conducting component is connected to the first end. The first end includes: a first lower end with a first pressing groove, a partition disposed in the first pressing groove along the depth direction, the height of the partition being less than the depth of the first pressing groove, the partition dividing the first pressing groove into a battery receiving groove and a horn groove, and the width of the horn groove gradually increasing along the direction away from the battery receiving groove; and a first upper end, which is disposed opposite to the first lower end and can move toward the first lower end and press against the first lower end. The aforementioned patented technology, by incorporating a silicone thermal pad, buffers the pressure exerted by the upper and lower end caps on the first end cap, protecting the disc-shaped polymer lithium-ion battery. Simultaneously, it reduces heat transfer from the first end cap to the aluminum-plastic film, preventing the PP adhesive layer of the aluminum-plastic film from over-melting and causing the aluminum layers of the two films to contact, thus preventing a short circuit in the insulation of the lithium-ion battery. Therefore, this technology still falls under the category of soft-seal end cap technology improvement, because the thermal conductivity of the silicone thermal pad in the soft-seal seal (the horn groove) is inferior to that of a copper end cap. While the patented technology includes a depth partition with a height less than the first pressing groove, this partition primarily blocks heat radiation from the lower part of the first pressing groove, but it cannot block heat transfer from the aluminum layer above the first pressing groove after contact with the aluminum-plastic film.

[0005] The biggest difference between soft sealing and hard sealing processes is that, in order to reach the melting point of the PP layer of the aluminum-plastic film, the temperature of the soft sealing process is 20-80℃ higher than that of the hard sealing process. Therefore, when the diameter of the round battery cell to be sealed is small (about Φ10mm), the higher the sealing temperature is set, the more heat is transferred from the aluminum layer and radiated from the sealing head during sealing, and the higher the risk of the PP adhesive layer at the injection hole melting and causing the injection hole to close.

[0006] During the electrolyte filling process of a soft-pack button cell, the electrolyte is injected into the cell's gas bag through the end of the gas bag hole. After vacuum adsorption, the electrolyte seeps into the cell's electrode assembly through the injection hole. If the PP layer at the injection hole melts and closes, the electrolyte will not easily enter the electrode assembly even under vacuum adsorption, leading to filling failure. If the PP layer at the injection hole does not melt, due to the small size of the injection hole and the special fit between the electrode assembly and the casing, the electrolyte does not easily seep in. Under negative pressure and static conditions, the electrolyte will flow towards the end of the gas bag hole. If there is an unsealed area at the end of the gas bag, the electrolyte is very likely to overflow from the gas bag in the unsealed area of ​​about 1 mm, leading to filling failure.

[0007] In summary, the disadvantages of flexible encapsulation structures are as follows: First, flexible encapsulation structures lack an unsealed leading edge area, making the tab adhesive prone to deformation. Furthermore, the silicone strip in the flexible encapsulation structure requires regular replacement, resulting in higher processing and material costs for both the encapsulation head and the adhesive strip. Additionally, because flexible encapsulation heads incorporate a silicone thermal pad, its thermal conductivity is inferior to that of copper encapsulation heads. To reach the melting point of the PP layer in the aluminum-plastic film, the temperature during the flexible encapsulation process is 20-80°C higher than that of the hard encapsulation process. The more heat transferred from the aluminum layer and radiated from the encapsulation head during encapsulation, the higher the risk of the PP adhesive layer at the injection hole melting and causing the injection hole to close. Second, the battery cell body is located on one side of the encapsulation head, leading to uneven stress on the upper and lower heads. Prolonged use can cause deformation, resulting in a shorter lifespan for the encapsulation head.

[0008] To address the technical shortcomings of the aforementioned soft-pack structure, there is an urgent need to develop a sealing head device that uses a hard-pack structure to encapsulate soft-pack button batteries. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of the above-mentioned technologies and provide a hard-sealing device for soft-pack button batteries. The wide-mouth design helps the device to automatically expand the hole and facilitates liquid injection. The liquid injection hole maximization design method and the design of the upper and lower heat insulation plates solve the problem of liquid injection hole closure caused by heat conduction and heat radiation when packaging cells with a diameter of about 10mm.

[0010] To achieve the above objectives, the present invention adopts the following technical solution: a hard-sealing device for a soft-pack button battery, comprising upper and lower sealing heads, characterized in that: the lower sealing head includes a lower sealing head base, a lower left limiting platform, a lower right limiting platform, a lower reinforcing platform, and a lower sealing platform; the lower sealing head base has a lower sealing platform in the middle, and the lower left limiting platform and the lower right limiting platform are respectively provided on both sides of the lower sealing platform; the lower sealing platform has a lower reinforcing platform matching its shape on its inner side, forming an integral lower sealing head structure; the lower sealing platform is arranged along the length direction of the lower sealing head base; the lower sealing platform includes a circular sealing area for accommodating the battery cell body. The straight sealing area of ​​the core air bag and the trapezoidal transition sealing area between the circular sealing area and the straight sealing area constitute a wide-mouth sealing area. The upper sealing head includes an upper sealing head seat, an upper left limiting platform, an upper right limiting platform, an upper reinforcing platform, and an upper sealing platform. The structure of the upper sealing head is the same as that of the lower sealing head and they are set in corresponding positions to form a symmetrical upper and lower sealing head structure. After the upper left limiting platform and the lower left limiting platform, as well as the upper right limiting platform and the lower right limiting platform, come into contact, there is a hard sealing gap between the upper sealing platform and the lower sealing platform. The upper surfaces of the upper and lower reinforcing platforms are respectively provided with heat insulation plates that are lower than the height of the sealing platform.

[0011] Furthermore, the hard-sealing gap is 80%-90% of the thickness of the aluminum foil battery cell air bag.

[0012] Furthermore, the junction between the circular sealing area and the trapezoidal transition sealing area is designated as an injection hole, the width of which is equal to or equal to the inner diameter Φ of the arc-shaped end cap. -0.5 .

[0013] Furthermore, the upper and lower end caps are provided with positioning slots for adjusting the end cap spacing, and there are at least 4 positioning slots, which are evenly distributed at the 4 apex corners of the end cap.

[0014] Furthermore, the upper left and right limiting platforms and the lower left and right limiting platforms are respectively provided with electrode tab slot arcs on their inner sides. After the upper and lower end caps come into contact, the electrode tab slot arcs form two independent cavities. The cavities are used to accommodate the positive and negative electrode tabs and to serve as encapsulation overflow grooves.

[0015] Furthermore, the included angle between the trapezoidal transition sealing areas of the upper and lower sealing platforms ranges from 0° to 180°.

[0016] Furthermore, the upper and lower sealing platforms have symmetrical tab adhesive limiting grooves on the circular sealing areas that accommodate the battery cell body.

[0017] Furthermore, the height of the upper and lower reinforcing platforms is lower than the height of the sealing platform.

[0018] Furthermore, the lower sealing platform is arranged along the width direction of the lower sealing head seat, and the upper sealing platform is correspondingly arranged along the width direction of the upper sealing head seat.

[0019] Furthermore, the insulation board is made of polytetrafluoroethylene or mahogany.

[0020] Furthermore, the linear sealing area of ​​the upper and lower sealing platforms extends to the end of the cell air bag opening.

[0021] Beneficial effects: Compared with existing technologies, the hard-seal head structure and wide-mouth sealing area design of this invention facilitate automatic liquid injection after the device expands the hole. The design of the reinforcing platform helps to enhance the rigidity of the sealing area. The symmetrical design of the seal along both sides of the transverse center line of the head ensures balanced stress on the head, which can prevent deformation of the head to a certain extent. This hard-seal head structure for soft-pack buckles not only solves the problem of electrode tab deformation caused by soft-pack encapsulation, but also saves material costs because it eliminates the need to replace the silicone strip / plate of the head. Furthermore, it facilitates hole expansion and liquid injection, ensures the strength of the head, and extends its service life. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the upper and lower end caps and the double-sided sealed battery cell;

[0023] Figure 2 This is a schematic diagram of the battery cell after it has been packaged.

[0024] Figure 3This is a schematic diagram of the liquid injection port and injection hole of the battery cell.

[0025] Figure 4 This is a top view of the top end cap;

[0026] Figure 5 This is a top view of the lower head;

[0027] Figure 6 This is a schematic diagram showing the height difference between the upper and lower end caps.

[0028] Figure 7 This is a three-dimensional structural schematic diagram of the present invention;

[0029] Figure 8 This is a schematic diagram showing the sealing platform positioned along the width of the sealing head seat.

[0030] In the diagram: 1. Upper end cap; 1-1. Upper left limiting platform; 1-2. Upper right limiting platform; 1-3. Positioning groove; 1-4. Upper electrode lug slot arc; 1-5. Upper sealing platform; 1-5-1. Circular sealing area; 1-5-2. Straight sealing area; 1-5-3. Trapezoidal transition sealing area; 1-5-4. Electrode lug adhesive limiting groove; 1-6. Upper reinforcing platform; 1-7. Upper heat insulation plate; 1-8. Upper end cap seat.

[0031] 2. Lower end cap; 2-1. Lower left limiting platform; 2-2. Lower right limiting platform; 2-3. Positioning long groove; 2-4. Lower electrode lug empty groove arc; 2-5. Lower sealing platform; 2-5-1. Circular sealing area; 2-5-2. Straight sealing area; 2-5-3. Trapezoidal transition sealing area; 2-5-4. Electrode lug adhesive limiting groove; 2-6. Lower reinforcing platform; 2-7. Lower heat insulation plate; 2-8. Lower end cap seat;

[0032] 3. Double-sided sealed battery cell; 4. Liquid injection port size W0; 5. Liquid injection hole size W; Detailed Implementation

[0033] To better understand the above-mentioned objects, features, and advantages of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. The described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the present invention.

[0034] In the various embodiments of the present invention, for ease of description and not limitation of the invention, the term "connection" used in the present invention patent application specification and claims is not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Above," "below," "underneath," "left," "right," etc., are only used to indicate relative positional relationships, and when the absolute position of the described object changes, the relative positional relationship also changes accordingly.

[0035] As shown in the attached drawings, this embodiment provides a hard-sealing device for a soft-pack button battery, including an upper sealing head 1 and a lower sealing head 2. The lower sealing head includes a lower sealing head seat 2-8, a lower left limiting platform 2-1, a lower right limiting platform 2-2, a lower reinforcing platform 2-6, and a lower sealing platform 2-5. The lower sealing head seat has a lower sealing platform in the middle, and the lower left limiting platform and the lower right limiting platform are respectively provided on both sides of the lower sealing platform. The lower sealing platform has a lower reinforcing platform with a matching shape on its inner side, forming an integral lower sealing head structure. The lower sealing platform is arranged along the length direction of the lower sealing head seat. The lower sealing platform includes a circular sealing area 2-5-1 for accommodating the battery cell body and a linear sealing area for the battery cell air bag. The sealing area 2-5-2 and the trapezoidal transition sealing area 2-5-3 between the circular sealing area and the straight sealing area constitute a wide-mouth sealing area. The upper sealing head includes an upper sealing head seat 1-8, an upper left limiting platform 1-1, an upper right limiting platform 1-2, an upper reinforcing platform 1-6, and an upper sealing platform 1-5. The structure of the upper sealing head is the same as that of the lower sealing head and they are arranged in corresponding positions to form a symmetrical upper and lower sealing head structure. After the upper left limiting platform and the lower left limiting platform, as well as the upper right limiting platform and the lower right limiting platform, come into contact, a hard sealing gap is provided between the upper sealing platform and the lower sealing platform. The upper surfaces of the upper and lower reinforcing platforms are respectively provided with heat insulation plates that are lower than the height of the sealing platform.

[0036] In a preferred embodiment, the hard-sealing gap is 80%-90% of the thickness of the aluminum foil battery cell air bag.

[0037] In a preferred embodiment, the junction between the circular sealing area and the trapezoidal transition sealing area is designated as an injection hole, and the width W0 of the injection hole is equal to or equal to the inner diameter Φ of the arc-shaped end cap. -0.5 .

[0038] In a preferred embodiment, the upper and lower end caps are provided with positioning grooves 1-3 and 2-3 for adjusting the end cap spacing. The number of positioning grooves is at least 4. In this embodiment, four are selected and evenly distributed at the 4 apex corners of the end cap.

[0039] In a preferred embodiment, the upper left and right limiting platforms and the lower left and right limiting platforms are respectively provided with tab slot arcs 1-4 and 2-4. After the upper and lower end caps come into contact, the tab slot arcs form two independent cavities. The cavities are used to accommodate the positioning fixtures of the battery cell, the positive and negative tabs, and as a packaging overflow groove.

[0040] In a preferred embodiment, the included angle between the trapezoidal transition sealing areas of the upper and lower sealing platforms ranges from 0° to 180°. When the cell diameter is ≥15mm, i.e., when the injection hole size is sufficient to meet the injection requirements of the automatic equipment, the included angle can be 0°.

[0041] In a preferred embodiment, the upper and lower sealing platforms have symmetrically arranged tab adhesive limiting grooves 1-5-4 and 2-5-4 on the circular sealing areas that accommodate the battery cell body. The tab adhesive limiting grooves can be arranged symmetrically or asymmetrically on the circular sealing areas.

[0042] In a preferred embodiment, the height of the upper and lower reinforcing platforms is lower than the height of the sealing platform.

[0043] The end cap is 100mm long, 25mm wide, and 30mm high. The reinforcing platform is 5mm thick, and the insulation board is 2mm thick. The upper and lower limiting platforms are 15mm high. After the end cap is integrally formed, the insulation board is installed on top of the reinforcing platform of the end cap.

[0044] See appendix for details Figure 8 Alternatively, in this embodiment, the lower sealing platform can be set along the width direction of the lower sealing head seat, and the upper sealing platform can be set accordingly along the width direction of the upper sealing head seat.

[0045] In a preferred embodiment, the linear sealing areas of the upper and lower sealing platforms extend to the end of the cell's air bag opening. That is, the linear sealing area needs to be sealed to the end of the air bag, leaving no unsealed area after sealing. Currently, most sealing heads leave a 1mm unsealed area. However, for soft-pack button cells, if there is a 1mm unsealed area, the electrolyte will overflow from this 1mm gap during electrolyte injection. Therefore, the 1mm unsealed area needs to be cut off before electrolyte injection / no unsealed area needs to be left during sealing.

[0046] The structure of the present invention will be further described in conjunction with the embodiments.

[0047] The device includes an upper end cap 1 and a lower end cap 2. Each end cap is equipped with a symmetrically designed limiting platform, a symmetrically designed positioning groove for adjustable end cap positions, an upper and lower arc-shaped relief lug slot, upper and lower sealing areas, upper and lower reinforcing platforms, and upper and lower heat insulation plates. The upper and lower end caps are made of copper and machined into a single structure in a digital machining center.

[0048] The width of the injection hole is equal to or equal to the inner diameter of the arc-shaped end cap.-0.5 The design maximizes the size of the injection hole and features an axially symmetrical seal along the length of the end cap.

[0049] The limiting platforms are symmetrically located at both ends of a single end cap, and the upper and lower limiting platforms have a symmetrical structure.

[0050] The adjustable end cap positioning slots include at least four slots on each end cap, evenly distributed at the four apex corners of the end cap, and each positioning slot is racetrack-shaped. This embodiment uses four slots.

[0051] The upper and lower end caps are respectively provided with two independent tab slot arcs. After the upper and lower end caps are compacted, they form two independent cavities. These cavities are used to accommodate positioning fixtures and positive and negative tabs, and also serve as encapsulation overflow grooves.

[0052] The upper and lower sealing areas are mainly composed of three parts: 1 is the circumferential sealing area of ​​the battery cell body, 2 is the linear sealing area of ​​the battery cell air bag, and 3 is the trapezoidal transition sealing area between the two areas.

[0053] The trapezoidal sealing area is designed with an angle ranging from 0 degrees to 180 degrees. (For example, at 180 degrees, it presents an Ω-shaped seal.)

[0054] The upper and lower sealing areas are respectively provided with tab adhesive limiting grooves, which can be extended at various angles on the circumferential seal of the sealing head.

[0055] The upper and lower reinforcing platforms are lower than the sealing plane. The purpose of the reinforcing platforms is to increase the rigidity of the sealing platform. Because the sealing area is relatively narrow (1.3-1.6mm), the structural rigidity of the sealing wall set alone on the sealing starting plane is poor. The inner side is reinforced with a platform to provide support, increase its rigidity and strength, and increase its service life.

[0056] The upper and lower heat insulation plates are placed on the inner upper surface of the reinforcement platform, and the height of the heat insulation plates is lower than the sealing plane. The heat insulation plates are made of non-metallic materials with poor thermal conductivity, such as polytetrafluoroethylene or mahogany.

[0057] In the design of the hard seal head, the upper sealing area and the lower sealing area are arranged symmetrically on both sides of the center line along the length of the seal head.

[0058] In the hard-seal head design, the sealing limit dimensions of the upper sealing area and the lower sealing area, i.e. the hard-seal gap, can be arranged on one seal head alone or on two seal heads.

[0059] Work process

[0060] During encapsulation, the double-sided sealed cell 3 is placed on the positioning fixture of the encapsulation equipment. The cell is precisely positioned using the encapsulation positioning slot. Then, the equipment turntable rotates to the primary encapsulation station. After the lower sealing head moves upward, the upper sealing head presses down, completing the encapsulation process in one step. The encapsulation parameters are: temperature 170-190℃, pressure 0.2-0.4Mpa, time 2-3s. Afterward, the cell is transferred to the Hi-pot testing station to complete the Hi-pot test.

[0061] Structural features of the embodiment

[0062] See appendix for details Figure 6 1. The structure of this invention maximizes the design of the injection hole W (the width of the injection hole is equal to or equal to the inner diameter of the arc-shaped end cap Φ). -0.5 The insulation plate partially isolates the heat radiation energy of the end cap, making it difficult for the injection hole to close; to facilitate automatic equipment injection, the injection port W0 size is ≥20mm, and the size of W is maximized in the design, i.e. (seal inner diameter).

[0063] 2. This end cap structure can complete the battery cell encapsulation in one go, improving the battery cell manufacturing efficiency;

[0064] 3. The upper and lower sealing platforms of this end cap structure are arranged along the axial direction of the upper and lower reinforcing platforms, so that the air bag seal is parallel to the end cap base, resulting in a narrow overall width of the end cap, easy processing accuracy, and a longer service life than end caps with a wider overall width.

[0065] 4. When there is a large difference in the encapsulation thickness between the air bag side and the battery cell body side, it can be adjusted by using the positioning slots on the left and right end caps.

[0066] The hard-sealing structure of this invention effectively prevents the injection port from closing during heat sealing, thus avoiding the inability to inject electrolyte. It also improves the machining accuracy of the end cap and extends its service life.

[0067] The maximizing sealing design of the injection hole in this invention facilitates automatic injection after hole enlargement. The reinforcement platform design enhances the rigidity of the encapsulation area. The symmetrical design of the seal along both sides of the transverse center line of the end cap ensures balanced stress on the end cap, preventing deformation to some extent. The upper and lower heat insulation plates help block heat radiation energy from the end cap, preventing the aluminum-plastic PP layer at the injection hole from closing due to heat. This soft-pack buckle battery hard-seal end cap structure not only solves the deformation of the tab adhesive caused by soft-pack encapsulation but also eliminates the need to replace the end cap silicone strip / plate, saving material costs. It also solves the problem of sealing the injection hole of small-diameter cells caused by high temperatures in soft-pack end caps, facilitating hole enlargement and injection, ensuring end cap strength, extending its service life, and enabling double-sided sealing in one operation, thus improving production efficiency.

[0068] See appendix for details Figure 7 In the figure, △1 is the height difference between the plane where the upper end cap limiting platform is located and the plane where the upper end cap sealing platform is located;

[0069] △2 represents the height difference between the plane where the lower head limiting platform is located and the plane where the lower head sealing platform is located;

[0070] △3 is the height difference between the plane where the sealing platform at the upper end cap ear is located and the plane where the sealing area (1-5a / 5b) of the upper end cap is located;

[0071] △4 represents the height difference between the plane where the sealing platform at the lower end cap's lug is located and the plane where the sealing area (2-5a / 5b) of the lower end cap is located;

[0072] Example 1:

[0073] See appendix for details Figure 8 Taking a silver-shell aluminum-plastic composite with a thickness of 113µm, a positive and negative tab substrate thickness of 0.08mm, and a tab adhesive layer with a thickness of 0.08mm (i.e., a total tab thickness of 0.24mm at the tab adhesive area) as an example, with the air bag's limits all set on the lower end cap and the positive and negative tabs led out in a collinear manner:

[0074] △1=0, △3=85±5um, △2=200±5um, △4=85±5um. β=180°

[0075] Example 2:

[0076] Taking a silver-cased aluminum-plastic coating with a thickness of 113µm, a positive and negative tab substrate thickness of 0.08mm, and a tab adhesive layer with a thickness of 0.08mm (i.e., a total tab thickness of 0.24mm at the tab adhesive area) as an example, with the air bag's limits all set on the upper end cap and the positive and negative tabs led out in a collinear manner:

[0077] △1=200±5um, △3=85±5um, △2=0, △4=85±5um. β=180°

[0078] Example 3:

[0079] Taking a silver-cased aluminum-plastic coating with a thickness of 113µm, a positive and negative tab substrate thickness of 0.08mm, and a tab adhesive layer with a thickness of 0.08mm (i.e., a total tab thickness of 0.24mm at the tab adhesive area) as an example, with the air bag's limiting position set on the upper and lower end caps, and the positive and negative tabs being led out in a collinear manner:

[0080] △1=100±5um, △3=85±5um, △2=100±5um, △4=85±5um. β=180°

[0081] The above three examples satisfy △1+△2=200±5um and △3+△4=170±5um. Specific Implementation Example 4:

[0083] Taking a silver-cased aluminum-plastic coating with a thickness of 113µm, a positive and negative tab substrate thickness of 0.08mm, and a tab adhesive layer with a thickness of 0.08mm (i.e., a total tab thickness of 0.24mm at the tab adhesive area) as an example, with the air bag's limits all set on the lower end cap, and the positive and negative tabs not collinearly led out:

[0084] △1=0, △3=85±5um, △2=200±5um, △4=85±5um. β=120°

[0085] The fundamental difference between rigid and flexible sealing heads lies in the different equipment parameters and tab materials used due to their different structures. Flexible sealing requires a higher encapsulation temperature setting than rigid sealing. Furthermore, during mold closing, the flexible sealing structure uses a silicone thermal pad to buffer the pressure exerted by the upper sealing head 2 on the lower sealing head 1, preventing over-sealing. This is achieved by combining set time and pressure parameters. In contrast, the rigid sealing structure prevents over-sealing through sealing limits, reaching the melting point of the PP layer in the aluminum-plastic composite, and then combining appropriate pressure and time parameters to achieve sealing. This results in simpler sealing and a more aesthetically pleasing appearance.

[0086] Hard packaging parameters: temperature 165-195℃, pressure 0.2-0.5MPa, time 1-5s (parameters within this range can be achieved)

[0087] The encapsulation parameters used in this embodiment are: temperature 175±5℃, pressure 0.25±0.05MPa, and time 3±1s.

[0088] The above detailed description of a hard-sealing device for a soft-pack button battery with reference to the embodiments is illustrative rather than limiting. Several embodiments can be listed according to the defined scope. Therefore, changes and modifications without departing from the overall concept of the present invention should be within the protection scope of the present invention.

Claims

1. A hard-sealing device for a soft-pack button cell battery, comprising an upper sealing head and a lower sealing head, characterized in that: The lower end cap includes a lower end cap base, a lower left limiting platform, a lower right limiting platform, a lower reinforcing platform, and a lower sealing platform. The lower end cap base has a lower sealing platform in the middle, with the lower left and lower right limiting platforms respectively located on either side. A lower reinforcing platform with a matching shape is located inside the lower sealing platform, forming an integral lower end cap structure. The lower sealing platform is arranged along the length of the lower end cap base. The lower sealing platform includes a circular sealing area for accommodating the battery cell body, a linear sealing area for the battery cell air bag, and a sealing area between the circular and linear sealing areas. The trapezoidal transition sealing area forms a wide-mouth sealing area. The upper end cap includes an upper end cap seat, an upper left limiting platform, an upper right limiting platform, an upper reinforcing platform, and an upper sealing platform. The structure of the upper end cap is the same as that of the lower end cap and they are set in corresponding positions to form a symmetrical upper and lower end cap structure. After the upper left limiting platform and the lower left limiting platform, as well as the upper right limiting platform and the lower right limiting platform, come into contact, a hard sealing gap is provided between the upper sealing platform and the lower sealing platform. The upper surfaces of the upper reinforcing platform and the lower reinforcing platform are respectively provided with heat insulation plates that are lower than the height of the sealing platform.

2. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The hard seal gap is 80%-90% of the thickness of the aluminum foil battery cell air bag.

3. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The junction between the circular sealing area and the trapezoidal transition sealing area is designated as an injection hole. The width of the injection hole is equal to or equal to the inner diameter Φ of the arc-shaped end cap. -0.5 .

4. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The upper and lower end caps are provided with positioning slots for adjusting the end cap spacing. There are at least four positioning slots, which are evenly distributed at the four apex corners of the end cap.

5. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The upper left and upper right limiting platforms, as well as the lower left and lower right limiting platforms, are respectively provided with electrode tab slot arcs on their inner sides. The electrode tab slot arcs form two independent cavities after the upper and lower end caps come into contact. The cavities are used to accommodate the positioning fixtures of the battery cell, the positive and negative electrode tabs, and as a packaging overflow groove.

6. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The included angle between the trapezoidal transition sealing areas of the upper and lower sealing platforms ranges from 0° to 180°.

7. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The upper and lower sealing platforms have circular sealing areas for accommodating the battery cell body, which are provided with tab adhesive limiting grooves.

8. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The height of the upper and lower reinforcing platforms is lower than the height of the sealing platform.

9. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The lower sealing platform is arranged along the width direction of the lower sealing head seat, and the upper sealing platform is arranged correspondingly along the width direction of the upper sealing head seat.

10. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The insulation board is made of mahogany.

11. The hard-sealing device for a soft-pack button battery according to claim 1, characterized in that: The linear sealing areas of the upper and lower sealing platforms extend to the end of the cell air bag opening.

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