Vacuum sealing device for soft package type secondary battery

Abstract

The utility model discloses a vacuum sealing device for a soft package type secondary battery, which comprises a box body, a vacuum sealing cavity is arranged in the box body, a battery cell placing area is arranged in the vacuum sealing cavity, and a laser heating emitter used for sealing heat fusion is arranged in the battery cell placing area. The vacuum sealing device for the soft package type secondary battery has the characteristics of accurate temperature control of the sealing head, high production efficiency and strong applicability.

Description

Technical Field

[0001] The utility model relates to the technical field of secondary batteries, in particular to a vacuum sealing device for soft-pack secondary batteries. Background Art

[0002] The post-liquid injection vacuum sealing machine (abbreviated as: battery sealing) currently commonly used by battery cell manufacturers places the battery cell after liquid injection into the cavity, uses a vacuum pump to evacuate the air in the cavity, and after the cavity reaches a negative pressure state, uses a hot pressing head to extrude, heat-seal and seal the aluminum-plastic film.

[0003] The specific working principle is that after the battery cells are assembled (i.e., placed in the shell) at room temperature, they are baked at high temperature and filled with liquid in a glove box under a certain humidity. After filling, some air is retained in the air pocket. The battery cells are placed into the cavity, and the vacuum device is activated to extract the excess gas from the battery's reserved air pocket. After reaching the predetermined vacuum level and vacuum holding time, the hot press seal head heat-seals the upper part of the reserved air pocket, completing the sealing process. The vacuum hot press sealer extracts the gas, and the vacuum holding time effectively prevents gas from entering the battery cells, effectively preventing adverse phenomena such as flatulence during the formation process.

[0004] Existing heat sealers seal the edges of soft-pack batteries tightly together through heating and compression. During the heating process, the inner layer of thermoplastic material (such as polyethylene or polypropylene) is heated above its softening point, making the surface of the material sticky. Pressure is then applied to ensure the two layers fit tightly together, forming a seal. During the cooling process, the thermoplastic material solidifies, forming a strong seal.

[0005] However, when heat-sealing soft-pack batteries, the aluminum-plastic film may be unevenly heated due to the uneven sealing head, resulting in incomplete sealing during heat-sealing extrusion, causing battery cell leakage during pressure formation; the battery cell may tilt after being placed in the vacuum chamber, and the heat-sealing offset may cause electrolyte leakage and contamination of the battery cell.

[0006] Specifically, the leakage of the hot pressing vacuum sealing machine is mainly reflected in the following aspects:

[0007] For example, leakage occurs at the aluminum-plastic film seal of the battery cell. If the heat sealing knife is uneven, the aluminum-plastic film bag opening may be heated unevenly, and the heat seal extrusion thickness may be uneven. During pressure formation, the excess electrolyte in the battery cell is squeezed and breaks through the thin heat seal edge of the aluminum-plastic film bag opening, causing leakage of the battery cell and increasing the product defect rate.

[0008] For example, the battery cell tilts and leaks in the vacuum chamber. In the vacuum chamber, due to the influence of vacuum exhaust, the battery cell may tilt, the aluminum-plastic film seal may shift during heat sealing, and the battery cell may leak and contaminate the battery cell, causing the battery cell to be scrapped. Utility Model Content

[0009] The utility model aims to provide a vacuum sealing device for soft-pack secondary batteries, which has the characteristics of precise sealing head temperature control, high production efficiency and strong applicability.

[0010] The utility model can be realized by the following technical solutions:

[0011] The utility model discloses a vacuum sealing device for soft-pack secondary batteries, comprising a box body, a vacuum sealing cavity provided in the box body, a battery cell placement area provided in the vacuum sealing cavity, and a laser heating emitter for sealing and thermal fusion provided inside the battery cell placement area.

[0012] Furthermore, a long, horizontal laser heating emitter runs horizontally between the two side walls of the cell placement area, with its length matching the width of the cell placement area. Furthermore, to ensure effective non-contact heat sealing, the laser heating emitter's irradiation angle can be adjusted to meet the packaging requirements of different locations.

[0013] Furthermore, a cold-pressed seal is provided on the top wall of the cell placement area to prevent damage to the aluminum-plastic film caused by a hot-pressed seal.

[0014] Furthermore, the top of the vacuum sealing chamber is connected to a vacuum exhaust pipe and a pressure relief pipe respectively, thereby achieving effective adjustment of the internal pressure of the vacuum sealing chamber.

[0015] Furthermore, the laser heating emitter can be a pulsed laser or a continuous wave laser. Pulsed lasers emit laser light in extremely short pulses, generating instantaneous high temperatures on the material surface, enabling precise heating and processing. Continuous wave lasers provide stable laser output and are suitable for applications requiring continuous heating, such as welding and heat treatment. They are able to maintain a constant temperature for an extended period of time.

[0016] Furthermore, the box body is a metal box body, and the vacuum exhaust pipe and the pressure relief pipe are sealed and connected to the vacuum sealing chamber body by using a quick connector. By using the quick connector, the vacuum exhaust pipe and the pressure relief pipe can be quickly installed and removed.

[0017] Furthermore, the soft-pack secondary battery is a lithium-ion battery or a sodium-ion battery, which meets the packaging needs of different types of secondary batteries.

[0018] Furthermore, soft-pack secondary batteries are encapsulated in aluminum-plastic film, which includes a central aluminum foil layer or plastic layers on both sides. Aluminum foil is the core layer of the film, typically ranging in thickness from 6 to 30 microns. It has excellent barrier properties, effectively preventing the penetration of moisture, oxygen, and light, protecting the contents from the external environment. Plastic layers are typically placed on both sides of the aluminum foil. Commonly used plastic materials include polyethylene (PE), polypropylene (PP), and polyester (PET). The plastic layers not only provide mechanical strength but also increase the film's flexibility and durability.

[0019] Furthermore, the sodium ion battery is a polyanion material battery, a layered oxide battery or a Prussian blue material battery, which meets the use needs of different types of secondary batteries.

[0020] Furthermore, the polyanion battery is a sodium iron phosphate battery or a sodium iron sulfate battery, which meets the use requirements of different types of sodium ion batteries.

[0021] The utility model provides a vacuum sealing device for soft-pack secondary batteries, which has the following beneficial effects:

[0022] First, the temperature control of the head is precise. The light beam irradiation heating method has the characteristics of high temperature controllable accuracy, concentrated heating area, and high control accuracy. It can effectively improve the sealing wrinkles caused by excessively high / low temperature of the hot pressing head and the leakage caused by weak inner layer bonding.

[0023] Second, the production efficiency is high. The laser beam irradiation heating speed is fast and the time is short. The laser beam can quickly heat-melt the inner layer of the aluminum-plastic film, and the head is sealed after extrusion, which greatly improves the production efficiency.

[0024] Third, it has strong applicability and avoids leakage caused by uneven hot pressing heads. When the aluminum-plastic film is heated, the unevenness of the hot pressing head will lead to uneven force on the aluminum-plastic film seal during extrusion, resulting in uneven seal thickness. During pressure formation, excessive electrolyte will break through the thin heat-sealed edge of the aluminum-plastic film bag, causing leakage in the battery cell and rendering the battery cell scrapped. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Attachment Figure 1 This is a schematic diagram of the exploded structure of a vacuum sealing device for soft-pack secondary batteries of the present invention;

[0026] The marks in the accompanying drawings include: 100, vacuum sealing cavity; 1, battery cell placement area; 2, vacuum exhaust pipe; 3, laser heating emitter; 4, cold pressing head; 5, pressure relief pipe. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in further detail below with reference to the embodiments and accompanying drawings.

[0028] like Figure 1 As shown, the present invention discloses a vacuum sealing device for soft-pack secondary batteries, comprising a housing, a vacuum sealing chamber 100 disposed within the housing, a cell placement area 1 disposed within the vacuum sealing chamber 100, and a laser heating emitter 3 disposed within the cell placement area 1 for heat-sealing the sealing. Specifically, the laser heating emitter is a pulsed laser or a continuous-wave laser.

[0029] like Figure 1 As shown, in order to achieve heat sealing, the laser heating emitter 3 is arranged in a long strip shape and is horizontally penetrated between the two side walls of the battery cell placement area 1, and the length of the laser heating emitter 3 is consistent with the width of the battery cell placement area 1.

[0030] like Figure 1 As shown, in order to achieve sealing, a cold pressing head 4 is also provided on the top wall of the battery cell placement area 1.

[0031] like Figure 1 As shown, in order to achieve air pressure adjustment, the top of the vacuum sealing chamber 100 is connected to a vacuum exhaust pipe 2 and a pressure relief pipe 5 respectively.

[0032] In the present invention, in order to ensure a longer service life, the box body is a metal box body, and the vacuum exhaust pipe and the pressure relief pipe are sealed and connected to the vacuum sealing chamber body using quick connectors.

[0033] The utility model has good applicability. The soft-pack secondary battery is a lithium-ion battery or a sodium-ion battery. Specifically, the sodium-ion battery is a polyanion battery, a layered oxide battery, or a Prussian blue battery. For example, the polyanion battery is a sodium iron phosphate battery or a sodium iron sulfate battery.

[0034] The device of the utility model can be applied to different types of aluminum-plastic films. Soft-pack secondary batteries are packaged and formed with the aluminum-plastic film, which includes an aluminum foil layer in the middle or plastic layers on both sides.

[0035] In this utility model, its specific operation process is:

[0036] The battery cell after liquid injection is placed in the battery cell placement area 1. The vacuum chamber is evacuated to a negative pressure state through the vacuum exhaust pipe 2 in the enclosed space inside the cavity. The edge position of the sealing setting is irradiated by adjusting the irradiation angle of the laser heating emitter 3. The laser heating method has the characteristics of fast heating speed, small heating area, and high control accuracy. In the vacuum chamber, the laser beam is irradiated to the surface of the aluminum-plastic film and heat-melts the hot melt adhesive of the inner layer of the aluminum-plastic film. The sealing purpose can be achieved by squeezing the sealing edge through the cold pressing head 4. Finally, the pressure relief pipe 5 enters the gas to relieve the pressure and then the battery cell is taken out.

[0037] In the description of the present invention, it should be understood that terms such as "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0038] Furthermore, 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 the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of this utility model, "plurality" means two or more, unless otherwise specifically defined.

[0039] In this utility model, unless otherwise expressly specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, indirect connection through an intermediate medium, or communication between two elements or interaction between two elements. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0040] The above embodiments are merely specific embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art will be able to make various modifications and improvements without departing from the scope of the present invention, and these obvious alternatives are all within the scope of protection of the present invention.

Claims

1. A vacuum sealing device for a soft-pack secondary battery, comprising a box body, wherein a vacuum sealing chamber is provided in the box body, characterized in that: A battery cell placement area is provided in the vacuum sealing cavity, and a laser heating emitter for sealing and thermal fusion is provided inside the battery cell placement area.

2. The vacuum sealing device for soft-pack secondary batteries according to claim 1, characterized in that: The laser heating emitter is in a long strip shape and is laterally arranged between the two side walls of the battery cell placement area, and the length of the laser heating emitter is consistent with the width of the battery cell placement area.

3. The vacuum sealing device for soft-pack secondary batteries according to claim 2, characterized in that: A cold-pressed seal is also provided on the top wall of the battery cell placement area.

4. The vacuum sealing device for soft-pack secondary batteries according to claim 3, characterized in that: The top of the vacuum sealing chamber is connected to a vacuum exhaust pipe and a pressure relief pipe respectively.

5. The vacuum sealing device for soft-pack secondary batteries according to claim 4, characterized in that: The laser heating emitter is a pulse laser or a continuous wave laser.

6. The vacuum sealing device for soft-pack secondary batteries according to claim 5, characterized in that: The box body is a metal box body, and the vacuum exhaust pipe and the pressure relief pipe are sealed and connected to the vacuum sealing box body through quick connectors.

7. The vacuum sealing device for soft-pack secondary batteries according to claim 6, characterized in that: The soft-pack secondary battery is a lithium-ion battery or a sodium-ion battery.

8. The vacuum sealing device for soft-pack secondary batteries according to claim 7, characterized in that: The soft-pack secondary battery is packaged and formed by an aluminum-plastic film, wherein the aluminum-plastic film includes an aluminum foil layer in the middle or plastic layers on both sides.

9. The vacuum sealing device for soft-pack secondary batteries according to claim 8, characterized in that: The sodium ion battery is a polyanion material battery, a layered oxide battery or a Prussian blue material battery.

10. The vacuum sealing device for soft-pack secondary batteries according to claim 9, characterized in that: The polyanion battery is a sodium iron phosphate battery or a sodium iron sulfate battery.

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