阅读说明：本技术 软包电池封装方法 (Soft package battery packaging method ) 是由 李峥 李清晖 王明辉 冯玉川 何泓材 于 2021-06-30 设计创作，主要内容包括：本发明涉及电池技术领域,具体公开了一种软包电池封装方法,软包电池封装方法包括步骤：S1、将电芯置于包装膜后,对折所述包装膜,使所述包装膜形成两个待封边开口侧及一个待注液开口侧；S2、对所述包装膜的两个所述待封边开口侧进行密封,以形成两个封边；对所述待注液开口侧进行点封,并形成粘连结构,所述点封能够使所述待注液开口侧形成注液口。由于形成两个封边后,半成品的软包电池需要注液,待注液开口侧不能进行封装,本发明提供的软包电池封装方法在注液前进行点封,从而有效防止待注液开口侧出现卷边,且点封方式能够保证待注液开口侧不被完全封装,以留有用于注液的注液口。(The invention relates to the technical field of batteries, and particularly discloses a method for packaging a soft-package battery, which comprises the following steps: s1, after the battery cell is placed in a packaging film, the packaging film is folded in half, and the packaging film forms two opening sides to be sealed and one opening side to be filled with liquid; s2, sealing the two opening sides of the packaging film to be edge sealed to form two edge seals; and the opening side of the liquid to be injected is point-sealed to form an adhesion structure, and the point-sealing can enable the opening side of the liquid to be injected to form a liquid injection port. After two sealed edges are formed, the semi-finished soft package battery needs to be injected with liquid, and the opening side of the liquid to be injected cannot be packaged.)

1. A method for packaging a soft package battery is characterized by comprising the following steps:

s1, after the battery cell is placed in a packaging film, the packaging film is folded in half, and the packaging film forms two opening sides (20) to be sealed and an opening side (30) to be injected with liquid;

and S2, treating the side of the opening of the liquid injection opening to adhere the two aluminum-plastic film layers on the side of the liquid injection opening.

2. The packaging method of the soft package battery is characterized in that after the side of the opening to be injected with liquid is treated, at least two adhesion structures (301) formed by two layers of aluminum plastic films are arranged on the side of the opening to be injected with liquid; and a liquid injection port is formed between the adhesion structures (301).

3. The pouch cell packaging method according to claim 2, characterized in that the area of the single adhesive structure (301) is not less than 0.25mm²。

4. The packaging method for the soft package battery according to claim 2, further comprising the steps of:

s3, clamping the adhesion structure (301) by a liquid injection device, and injecting liquid through the liquid injection port;

s4, pre-sealing the side (30) of the liquid to be injected after the adhesion, and forming a pre-sealing edge (302).

5. The pouch cell packaging method according to claim 2, wherein the adhesive structure (301) is formed by a point sealing mechanism, the point sealing mechanism comprises an upper sealing head and a lower sealing head, the upper sealing head comprises a convex part, and the lower sealing head comprises a concave part matched with the convex part;

the treating the side of the opening of the liquid to be injected to partially adhere the two layers of aluminum-plastic films on the side of the opening of the liquid to be injected comprises the following steps:

and placing the opening side (30) of the liquid to be injected on the lower end socket, and pressing the convex part and the concave part to form the adhesion structure (301).

6. The packaging method of the soft package battery according to claim 5, wherein the packaging temperature for the point sealing mechanism to perform the adhesion is 190 ℃ ± 10 ℃, and the packaging pressure is 0.3-0.5 kpa.

7. The method for packaging the soft package battery according to claim 2, wherein the number of the adhesion structures (301) is at least two, and the adhesion structures (301) are arranged on both sides of a center line in the length direction of the opening side (30) for the liquid to be injected.

8. The method for packaging the soft package battery according to claim 7, wherein the liquid injection port is formed between two adjacent adhesive structures (301).

9. The pouch battery packaging method according to any one of claims 2 to 8, characterized in that the adhesive structure (301) is not more than 10mm from the edge of the opening side (30) to be filled with liquid.

10. The pouch cell packaging method according to claim 4, wherein the adhesive structure (301) is overlapped with the pre-sealing edge (302).

Technical Field

The invention relates to the technical field of batteries, in particular to a packaging method of a soft package battery.

Background

Laminate polymer battery adopts the plastic-aluminum membrane to encapsulate electric core among the prior art, and the encapsulation process of electric core is: punching a pit on the aluminum-plastic film to form a pit for accommodating the battery core; placing the battery core into the pit; folding the aluminum-plastic film in half, wherein the opposite side of the folding line of the aluminum-plastic film is a top part, the two sides are side parts, and top sealing and side sealing are respectively carried out on the top part and one of the side parts by using packaging equipment; and injecting electrolyte or liquid additive into the battery cell through the side part without edge sealing, standing and pre-packaging the side part without packaging to form a semi-finished soft package battery.

However, after top sealing and side sealing, before liquid injection and pre-packaging, the side part of the semi-finished soft package battery without edge sealing is placed for a long time, and the larger the size of a single soft package battery is, the more obvious the edge rolling phenomenon is (see fig. 3), which is likely to cause adverse effects on subsequent processes, for example, the clamping process of feeding and discharging such as standing cannot be successfully clamped, electrolyte or liquid additive cannot be accurately injected, or the clamping process of a single packaging film causes unbalance, so that the aluminum plastic film of the soft package battery is uneven and even torn under the influence of the gravity of the battery core.

Therefore, there is a need for a method for packaging or manufacturing a pouch battery to avoid the edge curling of the unsealed side.

Disclosure of Invention

The invention aims to provide a packaging method of a soft package battery, which is used for avoiding the phenomenon of edge curling on the opening side to be sealed.

In order to achieve the purpose, the invention adopts the following technical scheme:

a packaging method of a soft package battery comprises the following steps:

s1, after the battery cell is placed in a packaging film, the packaging film is folded in half, and the packaging film forms two opening sides to be sealed and one opening side to be filled with liquid;

and S2, treating the side of the opening of the liquid injection opening to adhere the two aluminum-plastic film layers on the side of the liquid injection opening.

Preferably, after the side of the opening to be injected is treated, at least two adhesion structures formed by two layers of aluminum plastic films on the side of the opening to be injected are formed; and a liquid injection port is formed between the adhesion structures.

Preferably, the area of the single adhesion structure is not less than 0.25mm²。

Preferably, the method further comprises the following steps:

s3, clamping the adhesion structure by a liquid injection device, and injecting liquid through the liquid injection port;

s4, pre-sealing the side of the liquid injection opening to be adhered, and forming a pre-sealed edge.

Preferably, the adhesion structure is formed through a point sealing mechanism, the point sealing mechanism comprises an upper sealing head and a lower sealing head, the upper sealing head comprises a convex part, and the lower sealing head is provided with a concave part matched with the convex part;

the treating the side of the opening of the liquid to be injected to partially adhere the two layers of aluminum-plastic films on the side of the opening of the liquid to be injected comprises the following steps:

and placing the opening side of the liquid to be injected on the lower end enclosure, and pressing the convex part and the concave part to form the adhesion structure.

Preferably, the packaging temperature of the point sealing mechanism for carrying out the adhesion is 190 +/-10 ℃, and the packaging pressure is 0.3-0.5 kpa.

Preferably, the number of the adhesion structures is at least two, and the adhesion structures are arranged on two sides of a center line in the length direction of the opening side of the liquid to be injected.

Preferably, the liquid inlet is formed between two adjacent ones of the adhesion structures.

Preferably, the distance between the adhesion structure and the side edge of the liquid to be injected opening is not more than 10 mm.

Preferably, the adhesive structure coincides with the pre-seal edge.

The invention has the beneficial effects that:

after two sealed edges are formed, the semi-finished soft package battery needs to be injected with liquid, and the opening side of the liquid to be injected cannot be packaged.

Drawings

FIG. 1 is a schematic structural diagram of an aluminum plastic film provided by an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a semi-finished pouch battery provided by an embodiment of the invention;

fig. 3 shows a phenomenon of curling of a single pouch battery in the prior art.

In the figure:

1. an aluminum-plastic film; 11. a first pit; 12. a second pit;

2. an air bag;

10. folding the sides;

20. the side of the opening to be sealed; 201. side edge sealing; 202. top edge sealing;

30. the side of the liquid to be injected opening; 301. an adhesion structure; 302. pre-sealing edges;

40. and II, sealing edges.

Detailed Description

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some but not all of the elements associated with the present invention are shown in the drawings.

In the present invention, the directional terms such as "upper", "lower", "left", "right", "inner" and "outer" are used for easy understanding without making a contrary explanation, and thus do not limit the scope of the present invention.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The embodiment provides a method for packaging a soft package battery. As shown in fig. 1, the pouch battery includes a packaging film and a battery cell, the packaging film is used for covering the battery cell, and the aluminum-plastic film 1 is preferably an aluminum-plastic film 1. A first pit 11 for accommodating the battery core is provided, and the number of the first pits 11 can be one or two.

As shown in fig. 1 and fig. 2, the method for packaging a pouch battery provided in this embodiment includes the steps of:

s1, after the battery cell is placed in the first pit 11 of the aluminum-plastic film 1, folding the aluminum-plastic film 1 in half, so that the aluminum-plastic film 1 forms a folding side 10, two opening sides 20 to be edge-sealed and one opening side 30 to be injected with liquid;

and S2, treating the side 30 of the liquid injection opening to partially adhere the two aluminum-plastic films on the side of the liquid injection opening. In an optional embodiment, after the opening side of the liquid to be injected is treated, at least two adhesion structures 301 formed by two layers of aluminum plastic films on the opening side of the liquid to be injected are formed; and a liquid injection port is formed between the adhesion structures 301.

The application has no special requirement on the formation of the adhesion structure, and only needs to enable the upper and lower aluminum-plastic films to be bonded together to form a bonding force. The bonding means that the aluminum plastic films are heated and melted to be attached to each other, and the principle is the same as the melting in the packaging process. The formation of the adhesion structure can be performed by electric soldering iron, or by a packaging device similar to that used in packaging, including but not limited to the combination of an upper sealing head and a lower sealing head. As an embodiment, the upper and lower sealing heads may be provided with a convex or concave portion, or the upper and lower sealing heads may be directly shaped to have the same size as the adhesion structure. The adjustment of the distance between the adhesion structures 301 and the seal shape is realized by adjusting the convex parts of the upper end enclosure and the concave parts of the lower end enclosure.

Preferably, the adhesion is carried out through a point sealing mechanism, the point sealing mechanism comprises an upper sealing head and a lower sealing head, the upper sealing head comprises a convex part, and the lower sealing head is provided with a concave part matched with the convex part;

treat the side 30 of the opening of the liquid injection opening so that the partial adhesion of the two layers of aluminum-plastic films at the side of the liquid injection opening comprises:

the opening side 30 of the liquid to be injected is placed on the lower end enclosure, and the convex part and the concave part are pressed together to form an adhesion structure 301. The point sealing mechanism has a simple structure, is convenient to operate and is convenient to form the adhesion structure 301.

Furthermore, the packaging temperature for the point sealing mechanism to carry out adhesion is 190 +/-10 ℃, and the packaging pressure is 0.3-0.5kpa, so as to ensure the adhesion strength. Further, the area of the individual adhesive structures 301 is not less than 0.25mm²The upper limit of the area of the single adhesion structure 301 is limited by the pre-sealing edge 302 and the size of the liquid injection port, so as to further ensure the adhesion strength. The adhesive structure 301 may be in any shape, such as a line, a rectangular dot, a dot, or the like.

The adhesion structure 301 coincides with the pre-sealing edge 302 to prevent the adhesion structure 301 from occupying the position of the air bag 2, and ensure the volume of the air bag 2.

Preferably, the sealing edge and the sealing edge 40 have a sealing tension greater than or equal to 70N/15mm to prevent the cell from being pulled out.

As an embodiment, the method further includes sealing the two open sides 20 to be sealed of the aluminum plastic film 1 to form two sealed edges. Specifically, the two sealing edges are a side sealing edge 201 and a top sealing edge 202, respectively, the top sealing edge 202 is opposite to the folded edge side 10, and the side sealing edge 201 is opposite to the opening side 30 to be filled and is located between the top sealing edge 202 and the folded edge side 10.

The method for encapsulating the two open sides to be edge-sealed is not particularly limited, and any known top sealing and side sealing method can be used in the present application without departing from the inventive concept of the present application, including but not limited to encapsulating the corresponding positions of the aluminum plastic film by an upper sealing head and a lower sealing head which can be lifted and lowered in the vertical direction.

The packaging temperature is higher than the melting point of the aluminum-plastic film, and the upper layer and the lower layer of the folded aluminum-plastic film are fused and adhered through melting of the aluminum-plastic film at the packaging position.

In a preferred embodiment, the adhesive structure is located between the open side and a sealing position.

The first sealing refers to a process of sealing the liquid injection port after injecting the electrolyte or the liquid additive, which is also called as pre-sealing. After sealing, the inside of the battery core is isolated from the outside.

The adhesive structure is located outside a sealing position. Therefore, the adhesion structure does not have adverse effects on a sealing structure and the aluminum plastic film.

In this application, because the existence of adhesion structure for the upper and lower two-layer plastic-aluminum membrane of plastic-aluminum membrane notes liquid mouthful side bonds together, can not take place to stick up the limit, phenomenon such as curl, is favorable to going on of processes such as follow-up anchor clamps clamp is got, notes liquid rifle stretches into greatly.

As a preferable embodiment, the number of the adhesion structures 301 is at least two, and at least one adhesion structure 301 is disposed on both sides of a center line in a length direction of the opening side 30 to be injected with liquid.

The at least two adhesive structures 301 may be disposed equidistantly or non-equidistantly. The aluminum plastic film on the side of the liquid injection port is more smooth due to the uniform distribution of the adhesion structure.

In one embodiment, the number of the adhesive structures is one. Preferably, the adhesion structure is located at a central position on the side of the liquid injection port.

Although the single adhesion structure 301 has a simple process, when the adhesion structure is disposed at the center of the liquid injection port, most of the liquid injection in the process is performed at the center of the aluminum-plastic film, and therefore, the adhesion structure needs to be manually torn off and then the liquid injection is performed during the liquid injection. On one hand, the labor cost is increased, and on the other hand, the aluminum plastic film 1 is easy to deform due to manual operation errors; if mechanical equipment is adopted for automation, the deformation direction of the aluminum-plastic film has certain randomness, so that the precision requirement on the equipment is high, and the process difficulty is increased by the equipment needing customization.

Preferably, at least two adhesion structures 301 are arranged on the opening side 30 of the liquid to be injected, and the liquid injection port is positioned between the two adhesion structures 301.

Further preferably, the liquid inlet opening side 30 is provided with more than two sets of adhesion structures, each set of adhesion structures includes at least two adhesion structures, and each set of adhesion structures is equidistantly arranged.

Still further preferably, a liquid injection port is provided between each group of two connected adhesive structures.

The distance between the highest point and the lowest point of the aluminum plastic film liquid injection port side is less than 3 mm; preferably, less than 2 mm; more preferably, less than 1 mm.

The smaller the distance between the highest point and the lowest point is, the better the flatness of the aluminum-plastic film is represented, and the easier the subsequent processes are; simultaneously, annotate the liquid mouth and be located between two adjacent adhesion structures, when the plastic-aluminum membrane planarization between the adhesion structure is better, the more easy going on of notes liquid process that the liquid mouth was annotated in the dependence.

Preferably, the liquid injection port is formed between two adjacent adhesion structures 301. The number of the liquid injection ports can be one, two or more, and technicians can set the liquid injection ports according to actual use requirements. Adhesion structure 301's quantity can be more than the manipulator clamp of priming device and get the point of getting of semi-manufactured goods laminate polymer battery to when semi-manufactured goods laminate polymer battery was got to the manipulator clamp, adhesion structure 301's position was got to the manipulator clamp.

In the application, the length of the liquid injection port along the length direction of the opening side 30 of the liquid to be injected is not limited at all, the liquid injection nozzle of the liquid injection device can inject liquid, and the curling is not easy to cause, wherein the length of the exemplary opening side 30 of the liquid to be injected is 300-500mm, and the length of the liquid injection port is 95-110 mm. In an exemplary process of forming the adhesion structure, two dot-shaped sealing seals are formed on the opening side 30 to be injected by using two dot-shaped convex parts, an unpackaged injection port is formed between the two dot-shaped sealing seals, and when the length of the opening side 30 to be injected is longer, a technician can increase the number of the adhesion structures 301 after setting the injection port.

Preferably, the adhesive structure 301 is no more than 10mm from the edge of the opening side 30 for liquid to be injected to ensure that the gas bag 2 has a sufficient volume to contain the gas discharged from the formation process. Further, the distance from the edge of the liquid inlet opening side 30 to the adhesion structure 301 is 2-5mm, such as 2mm, 3mm or 5mm, to further ensure the strength of the adhesion structure 301.

Preferably, the packaging temperature of the point sealing mechanism for carrying out the adhesion is 190 +/-10 ℃, and the packaging pressure is 0.3-0.5 kpa.

Preferably, the area of the single adhesion structure is not less than 0.25mm²。

The adhesion structure 301 enables the opening side 30 to be filled with liquid to form a liquid filling port. It is understood that the present embodiment does not limit the formation sequence of the adhesive structure 301, the side seal 201, and the top seal 202.

Preferably, after step S2, the method further includes the steps of:

s3, clamping the adhesion structure 301 by the liquid injection device, and injecting liquid through the liquid injection port;

and S4, pre-sealing the side 30 of the liquid to be injected opening after adhesion, and forming a pre-sealing edge 302, so as to prevent the injected liquid from flowing out.

After the two sealed edges are formed, the semi-finished soft package battery needs to be injected with liquid, and the opening side 30 to be injected with the liquid cannot be packaged. Compare in treating to annotate liquid opening side 30 and do not do the encapsulation completely and can lead to the turn-up, annotate the liquid and can't accurately press from both sides when getting easily and get or press from both sides partial phenomenon, the laminate polymer battery encapsulation that this embodiment provided prevents when the priming device annotates liquid, and the priming device can be set for according to adhesion structure 301's position and press from both sides the position of getting, guarantees that the accuracy that back process pressed from both sides was got and the stability of centre gripping, has improved encapsulation efficiency greatly, and the benefit is high.

The application has no special requirements on the structure and the type of the aluminum plastic film. Any known aluminum plastic film that can be identified for soft pack lithium ion batteries can be used in the present application without departing from the inventive concept of the present application. The conventional structure of the aluminum plastic film is generally made of an outer insulating layer and an inner adhesive layer made of polymer materials, and a metal layer interposed between the outer insulating layer and the inner adhesive layer. The metal layer may be made of aluminum, but is not limited to this solution.

Preferably, after step S4, the method further includes the steps of:

s5, performing a formation process;

and S6, performing secondary sealing on one side of the pre-sealing edge 302 to form a secondary sealing edge 40, forming the air bag 2 between the secondary sealing edge 40 and the pre-sealing edge 302, and cutting off the air bag 2. The secondary sealing edge 40 can isolate gas discharged in the formation process from the battery cell and discharge the gas in a mode of cutting off the gas bag 2.

The formation has the effects of activating the battery, activating positive and negative electrode substances in the battery by utilizing low-current charging, and forming an SEI film on a negative electrode, so that the performance of the battery is more stable, and the battery can embody the real performance only after formation.

The formation process is not particularly limited in this application, and any known formation process can be used in this application without departing from the inventive concept of the present application, including but not limited to known constant current and constant voltage processes.

In most battery systems, the formation process generates gas inside the battery, and the generated gas enters the gas bag and is pumped out under negative pressure in the secondary sealing process.

The secondary sealing process refers to a process of packaging the inner side of the air bag for the second time after the battery is formed so as to separate the battery core from the air bag, after the secondary sealing process, the interior of the battery core is completely isolated from the external space, and external air and water vapor can not enter the battery core any more.

It is understood that the process of puncturing the air bag is included in the secondary sealing process and should be performed before the secondary sealing is actually performed. The present application does not require any particular method of puncturing the air bag to allow the generated gas to exit the cell, and any known method can be used without departing from the inventive concepts of the present application, including but not limited to puncturing the air bag with a bayonet that can move vertically up and down with the lifting mechanism.

The process of puncturing the air bag is preferably performed in a vacuum environment so that the gas can more quickly and efficiently leave the aluminum plastic film.

The present application does not require any special packaging process in the secondary sealing process, and any known secondary sealing process can be used in the present application without departing from the inventive concept of the present application, and the secondary sealing device can adopt the same equipment and process as the top sealing and the side sealing, including but not limited to packaging the aluminum-plastic film by using an upper sealing head and a lower sealing head which can move up and down in the vertical direction along with the lifting structure.

The battery cell is arranged in a coating area surrounded by the top sealing edge 202, the side sealing edge 201 and the secondary sealing edge 40, the coating area surrounded by the top sealing edge 202, the secondary sealing edge 40 and the pre-sealing edge 302 forms the air bag 2, and the area of the air bag 2 can be flushed with the second pit 12 or not.

One embodiment of the present invention is described below with reference to fig. 1-2:

the battery core is placed in the first pit 11 of the aluminum-plastic film 1, the aluminum-plastic film 1 is subjected to top sealing and side sealing by a packaging machine, and after a top sealing edge 202 and a side sealing edge 201 are formed, the semi-finished soft package battery is conveyed to a point sealing mechanism of the packaging machine. And arranging the 30 sides of the opening side of the liquid to be injected into a lower end enclosure of a point sealing mechanism, wherein the upper end enclosure is provided with two convex parts, the projection diameter of the convex parts is 0.6mm, the distance between the two convex parts is 100mm, the upper end enclosure is used for stamping the lower end enclosure, the distance between the convex parts and the concave parts is 3mm, the temperature is 190 ℃, and the pressure is 0.4kpa for adhesion. And after adhesion, injecting liquid into the aluminum plastic film 1 and pre-sealing the side 30 of the opening to be injected with the liquid to form a pre-sealed edge 302. After the pre-sealing is finished, aging and forming are carried out on the semi-finished soft package battery, secondary sealing is carried out after vacuum air exhaust, a secondary sealing edge 40 is formed to enclose the air bag 2, and the air bag 2 is cut off to finish the packaging of the soft package battery.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.