WO2023224270A1

WO2023224270A1 - Pouch type battery case sealing device and method

Info

Publication number: WO2023224270A1
Application number: PCT/KR2023/005117
Authority: WO
Inventors: 이근준; 백승구
Original assignee: 에스케이온 주식회사
Priority date: 2022-05-19
Filing date: 2023-04-14
Publication date: 2023-11-23
Also published as: KR20230161817A

Abstract

A pouch type battery case sealing device according to the present technology may comprise: a lower heat bar disposed below a sealing portion comprising at least one edge, among a plurality of edges, of a pouch type battery case in which an electrode assembly is accommodated; an upper sealing roller for heat-sealing the sealing portion while moving along the surface of the sealing portion from one end of the sealing portion toward the other end of the sealing portion; and an upper heat bar which is coupled to the sealing roller and transfers thermal energy to the sealing roller.

Description

Pouch type battery case sealing device and method

This technology relates to secondary batteries, and more specifically, this technology relates to a pouch-type battery case sealing device and method.

As the electronics, communications, and space industries develop, the demand for secondary batteries as an energy power source is rapidly increasing. In particular, as the importance of global eco-friendly policies is emphasized, the electric vehicle market is growing rapidly, and research and development on secondary batteries is being actively conducted at home and abroad.

A secondary battery includes an electrode assembly including a cathode, a cathode, and a separator disposed between them, and a battery case, which is an exterior material that seals and stores the electrode assembly together with an electrolyte. These secondary batteries may be classified into a pouch type, prismatic type, or cylindrical type depending on the shape and structure of the battery case. In particular, pouch-type secondary batteries are widely used due to the advantages of relatively free shape, simple structure, and large electric capacity per unit volume.

Embodiments of the present invention provide a pouch-type battery case sealing device and method.

A battery case sealing device according to an embodiment of the present invention includes a lower heat bar disposed below a sealing portion including at least one corner of a plurality of corners of a pouch-type battery case accommodating an electrode assembly, and one end of the sealing portion. It may include an upper sealing roller that heat-seals the sealing portion while moving the surface of the sealing portion in a direction from the other end of the sealing portion, and an upper heat bar that is coupled to the sealing roller and transmits heat energy to the sealing roller.

A method of sealing a pouch-type battery case accommodating an electrode assembly according to an embodiment of the present invention includes providing heat energy to a lower portion of a sealing portion including at least one edge among a plurality of edges of the pouch-type battery case. , providing heat energy to an upper sealing roller disposed on the upper part of the sealing part and in contact with the upper surface of the sealing part, and moving the sealing roller on the surface of the sealing part in the direction from one end of the sealing part to the other end of the sealing part. It can be included.

According to the present technology, a pouch-type battery case sealing device and method are provided.

1 is a diagram for explaining the structure of a pouch-type battery case accommodating an electrode assembly.

Figure 2 is a diagram for explaining another embodiment of a pouch-type battery case.

Figure 3 is a diagram for explaining a pouch-type battery case sealing device according to the prior art.

Figure 4 is a side view of the pouch-type battery case sealing device of Figure 3.

Figure 5 is a diagram for explaining a pouch-type battery case sealing device according to an embodiment of the present invention.

Figure 6 is a side view of the pouch-type battery case sealing device of Figure 5.

Figure 7 is a diagram for explaining a pouch-type battery case sealing device according to another embodiment of the present invention.

Figure 8 is a side view of the pouch-type battery case sealing device of Figure 7.

Figure 9 is a diagram for explaining a pouch-type battery case sealing device according to another embodiment of the present invention.

Figure 10 is a side view of the pouch-type battery case sealing device of Figure 9.

11 is a diagram for explaining various embodiments of a sealing roller.

Specific structural and functional descriptions of the embodiments according to the concept of the present invention disclosed in this specification or application are merely illustrative for the purpose of explaining the embodiments according to the concept of the present invention, and the implementation according to the concept of the present invention The examples may be implemented in various forms and should not be construed as limited to the embodiments described in this specification or application.

Referring to FIG. 1, the pouch-type battery 100 may include an electrode assembly (not shown) and a battery case 110 that accommodates the electrode assembly.

The pouch-type battery 100 may include electrode leads 150 and 160 extending from the electrode assembly. The electrode leads 150 and 160 are electrically connected to an electrode assembly (not shown) and are exposed to the outside of the battery case 110 to serve as electrode terminals that can be electrically connected to another battery or external device. The electrode leads 150 and 160 may include a positive electrode lead 150 and a negative electrode lead 160, respectively. The anode lead 150 and the cathode lead 160 may be made of different materials. For example, the positive electrode lead 150 may be made of the same material as the positive electrode, such as aluminum (Al), and the negative lead 160 may be made of the same material as the negative electrode, such as copper (Cu) or copper coated with nickel (Ni). You can.

The positive lead 150 and negative lead 160 may have a structure exposed to different sides of the battery case 110, respectively. In an embodiment, unlike the embodiment shown in FIG. 1, the positive lead 150 and the negative lead 160 may have a structure exposed side by side on one side of the battery case 110.

The electrode assembly (not shown) may have a laminated (stacked) structure in which an anode and a cathode are alternately stacked with a separator in between. However, in an embodiment of the present invention, the structure of the electrode assembly (not shown) is not limited to this, and may have a jelly roll (wound type) structure.

In an embodiment, the battery case 110 can accommodate an electrode assembly (not shown) and an electrolyte (not shown) in an internal space, and may be manufactured from a flexible material. In terms of structure, the battery case 110 may be formed of an outer layer, a metal layer, and an inner layer. The outer layer serves as a base material and a protective layer, and can primarily protect the electrode assembly (not shown) from external impacts. The outer layer may be formed of a polymer material such as nylon or polyethylene terephthalate (PET), but is not limited thereto. The metal layer may serve as a substrate that maintains mechanical strength and a barrier layer that prevents moisture and oxygen from penetrating, and may be formed of a material such as aluminum (Al), but is not limited thereto. The inner layer is also called a heat-sealing layer, and has heat-adhesive properties so it can act as a sealing agent. The inner layer can be formed of a polyolepin-based resin material, and can also act as an adhesive layer using CPP (Casted Polypropylene), a modified polypropylene. The inner layer may be formed of a material selected from the group consisting of polyolefin-based resins such as chlorinated polypropylene, polyethylene, ethylene propylene copolymer, polyethylene and acrylic acid copolymer, and polypropylene and acrylic acid copolymer, but is not limited thereto.

The battery case 110 protects internal components such as the electrode assembly (not shown) and electrolyte (not shown), and has a heat dissipation function and complements the electrochemical properties caused by the electrode assembly (not shown) and electrolyte (not shown). can be performed.

The battery case 110 may include a storage portion 120, a sealing portion 130, and a folding portion 140.

The storage unit 120 can accommodate an electrode assembly (not shown). Sealing on two sides of the battery case 110 as the positive lead 150 and negative lead 160 extending from the electrode assembly (not shown) are exposed from two different corners of the battery case 110. The sealing unit 130 where the process was performed may be located.

The sealing portion 130 may serve to seal the inside of the battery case 110 and prevent internal electrolyte from leaking or contact between the internal environment and the external environment.

In an embodiment, one side of the battery case 110 may include a folding portion 140 that is folded at least once as shown in FIG. 1 . However, embodiments of the present invention are not limited to the battery case 110 including the folding portion 140.

Referring to FIG. 2, the pouch-type battery 200 may include an electrode assembly (not shown) and a battery case 210 that accommodates the electrode assembly.

The pouch-type battery 200 may include electrode leads 250 and 260 extending from the electrode assembly. The electrode leads 250 and 260 may have the same configuration as the electrode leads 150 and 160 described with reference to FIG. 1 .

The battery case 210 may include an electrode assembly storage unit 220, a gas collection unit 230, and a sealing unit 240.

The electrode assembly storage unit 220 may have the same configuration as the storage unit 120 described with reference to FIG. 1 .

The gas collection unit 230 may be a part that collects gas generated during the initial activation process of the pouch-type battery 200. The gas collection unit 230 may be cut and removed from the pouch-type battery 200 after collecting the gas generated in the activation process. Since the battery case 210 is manufactured to include a gas collection part 230 during initial manufacturing, the battery case 210 of FIG. 2 has a relatively longer sealing part 240 compared to the battery case 110 of FIG. 1. It can be included. The sealing

parts

130 and 240 described with reference to FIGS. 1 and 2 may be sealed using a thermocompression method.

3 and 4, the pouch-type battery case sealing device 300 may include an upper heat bar 310, an upper sealing bar 320, a lower heat bar 330, and a lower sealing bar 340. there is.

The upper heat bar 310 is disposed on the upper sealing bar 320 and is in contact with the upper sealing bar 320. The upper heat bar 310 may be a means of transferring heat energy to the upper sealing bar 320. The lower heat bar 330 is disposed on the lower surface of the lower sealing bar 340 and is in contact with the lower sealing bar 340. The lower heat bar 330 may be a means of transferring heat energy to the lower sealing bar 340.

A sealing portion included on at least one corner of the pouch-type battery case may be disposed between the upper sealing bar 320 and the lower sealing bar 340 of the pouch-type battery case sealing device 300. While the lower sealing bar 340 of the pouch-type battery case sealing device 300 is fixed, the upper heat bar 310 and upper sealing bar 320 move in the direction (A-A') of the lower sealing bar 340. The sealing part can be sealed by applying heat and pressure to the sealing part while doing so. At this time, the surface temperature of the upper sealing bar 320 and the lower sealing bar 340 may be increased by the upper heat bar 310 and lower heat bar 330, respectively. In an embodiment, while the upper sealing bar 320 is fixed, the lower heat bar 330 and the lower sealing bar 340 move in the direction (A'-A) of the upper sealing bar 320, thereby generating heat and pressure in the sealing portion. The sealing part can be sealed by applying . In addition, in an embodiment, heat and pressure are applied to the sealing portion of the battery case disposed between the upper sealing bar 320 and the lower sealing bar 340 while the upper sealing bar 320 and the lower sealing bar 340 approach each other. The sealing part can be sealed using this method.

In the case of the battery case 110 including the folding portion 140, such as the battery case 110 described with reference to FIG. 1, the side surfaces are open, so when pressure is applied at once using sealing bars, the sealing portion becomes smooth. The electrode assembly or electrolyte contained inside cannot be sealed, and surface wrinkling may occur. That is, when sealing by applying pressure all at once using the pouch-type battery case sealing device 300, the surface of the sealing portion may become wrinkled and wrinkled (wrinkled or crumpled). In particular, as in the case of the battery case 210 described with reference to FIG. 2, the longer the length of the sealing part, the more severe the phenomenon of surface wrinkling may become. If the sealing part fails to seal the electrode assembly or electrolyte, a vent may occur or it may be difficult to ensure normal battery operation.

Referring to FIGS. 5 and 6 , the pouch-type battery case sealing device 500 may include an upper heat bar 510, sealing

rollers

520 and 530, and a lower heat bar 540. The sealing

rollers

520 and 530 may include a sealing wheel 520 and a fastening portion 530.

In Figure 5, the upper heat bar 510, the sealing

rollers

520, 530, and the lower heat bar 540 are shown as spaced apart from each other, but this is for convenience of explanation, and the pouch-type battery case sealing device 500 When sealing the sealing portion of the battery case 550, the upper heat bar 510 and the sealing

rollers

520 and 530 may be in contact with the lower heat bar 540, as shown in FIG. 6 .

The upper heat bar 510 may be connected to the sealing

rollers

520 and 530. Specifically, the upper heat bar 510 may be coupled to the fastening portion 530 of the sealing

rollers

520 and 530. The fastening part 530 may be mounted inside the upper heat bar 510 and may have a structure that can be moved from one end of the sealing part to the other end in the direction (B-B'). Accordingly, the sealing wheel 520 coupled with the fastening part 530 moves from one end of the sealing part in the direction (B-B') to the other end with the fastening part 530 mounted inside the upper heat bar 510. The sealing wheel 520 can heat-compress the sealing portion while moving the upper surface of the sealing portion.

In an embodiment, the upper heat bar 510 transfers heat energy to the fastening part 530 that contacts the upper heat bar 510, and the heat energy transferred to the fastening part 530 is transmitted to the sealing wheel 520. It can be. Through this, the sealing wheel 520 can heat-compress the sealing portion.

In an embodiment, the sealing

rollers

520 and 530 may move while rotating the surface of the sealing portion while the fastening portion 530 coupled to the upper heat bar 510 moves in the B-B' or B'-B direction.

The lower heat bar 540 may be disposed below the upper heat bar 510 and the sealing

rollers

520 and 530. The lower heat bar 540 may supply heat energy to the lower part of the sealing part.

In an embodiment, the direction in which the sealing

rollers

520 and 530 seal the sealing part of the battery case 550 is not limited to the direction from B to B', as long as it is from one end of the sealing part to the other end. That is, the sealing portion of the battery case 550 may be sealed in the direction from B' to B.

By using the pouch-type battery case sealing device 500 described with reference to FIGS. 5 and 6, the phenomenon of the sealing portion crying after sealing can be prevented.

Referring to FIGS. 7 and 8 , the pouch-type battery case sealing device 700 may include a lower heat bar 710, sealing

rollers

720 and 730, and an upper heat bar 740.

The embodiment of FIGS. 7 and 8 is a pouch-type battery case sealing in which the sealing

rollers

720 and 730 thermally compress upward from below the sealing portion of the battery case 750, rather than thermally compressing the sealing portion downward. Represents device 700.

In FIG. 7, the lower heat bar 710, the sealing

rollers

720, 730, and the upper heat bar 740 are shown to be spaced apart from each other, but this is for convenience of explanation, and the pouch-type battery case sealing device 700 When sealing the sealing portion of the battery case 750, the lower heat bar 710 and the sealing

rollers

720 and 730 may be in contact with the upper heat bar 740, as shown in FIG. 8 .

7 and 8, the pouch described in FIGS. 5 and 6 except that the sealing

rollers

720 and 730 are coupled to the lower heat bar 710 rather than the upper heat bar 740. The sealing portion of the battery case 750 can be sealed in the same manner as the type battery case sealing device 500. That is, the sealing wheel 720 coupled with the fastening part 730 moves from one end of the sealing part to the other end in the direction (C-C' or C'-C) with the fastening part 730 mounted inside the lower heat bar 710. As it moves, the sealing wheel 720 moves the lower surface of the sealing portion and can heat-compress the sealing portion.

9 and 10, the pouch-type battery case sealing device 900 includes an upper heat bar 910,

upper sealing rollers

930, 940, lower heat bar 920, and

lower sealing rollers

950, 960. may include.

9 and 10, the sealing roller does not move in either direction above or below the sealing part of the battery case 970, but the sealing roller moves at the top and bottom of the sealing part to cover the upper and lower surfaces of the sealing part. It shows a pouch-type battery case sealing device 900 that is heat-compressed.

9 and 10, the pouch-type battery case sealing device described with reference to FIGS. 5 to 8, except that the sealing roller is coupled to both the upper heat bar 910 and the lower heat bar 920 ( The sealing portion of the battery case 970 may be sealed in the same manner as 500 and 700). That is, the upper sealing wheel 930 and the lower sealing wheel 950 coupled with the

fastening parts

940 and 960 move from one end of the sealing part to the other end in the direction (D-D' or D'-D), thereby moving the upper and lower surfaces of the sealing part. The sealing part can be heat-compressed while moving simultaneously or sequentially.

In an embodiment, the upper ceiling wheel 930 and the lower ceiling wheel 950 may move in opposite directions.

In an embodiment, the upper ceiling wheel 930 and the lower ceiling wheel 950 may move sequentially. That is, the sealing part may be sealed in the order that the upper sealing wheel 930 first moves the upper surface of the sealing part, and then the lower sealing wheel 950 moves the lower surface of the sealing part.

11 is a diagram for explaining various embodiments of a sealing roller.

Referring to FIG. 11, the sealing roller may be mounted on the pouch-type battery

case sealing devices

500, 700, and 900 described through the embodiments of FIGS. 5, 7, and 9. Sealing rollers having various shapes and weights can be selected for optimal sealing effect depending on the material of the sealing part, length, type of material used as an internal sealing agent, etc.

The sealing roller may include a sealing wheel and a fastening part having a cylindrical shape that penetrates the sealing wheel. Depending on its shape, the sealing wheel is a rectangular (or cubic) shaped sealing wheel (a), a square pillar shaped sealing wheel with different widths on the upper and lower surfaces (b), and a cylindrical or elliptical pillar shaped sealing wheel (c). Alternatively, it may have various forms, such as a triangular pillar-shaped ceiling wheel (d).

Depending on the shape of the sealing wheel, the area or weight in contact with the sealing part may vary, and the optimal sealing wheel can be selected accordingly. FIG. 11 shows four types of sealing wheels (a) to (d), but in addition, sealing wheels of various shapes are shown in the pouch-type battery case sealing device described through the embodiments of FIGS. 5, 7, and 9. It can be mounted on

fields

500, 700, and 900.

Claims

a lower heat bar disposed below the sealing portion including at least one corner of a plurality of corners of the pouch-type battery case accommodating the electrode assembly;

an upper sealing roller that heat-seals the sealing portion while moving the surface of the sealing portion in a direction from one end of the sealing portion to the other end of the sealing portion; and

an upper heat bar coupled to the sealing roller and transmitting heat energy to the sealing roller; A battery case sealing device comprising a.
The method of claim 1, wherein the sealing roller is:

A battery case sealing device that rotates and moves while moving from one end of the sealing unit to the other end of the sealing unit.
The method of claim 1, wherein the upper sealing roller is:

an upper sealing roller fastening portion coupled to the upper heat bar and moving in a direction from one end of the sealing portion to the other end of the sealing portion while coupled to the upper heat bar; and

A battery case sealing device comprising: an upper sealing wheel that is coupled to an upper sealing roller fastening portion and moves on the surface of the sealing portion as the upper sealing roller fastening portion moves from one end of the sealing portion to the other end of the sealing portion.
The method of claim 3, wherein the upper sealing wheel is:

A cylindrical battery case sealing device.
According to clause 1,

A battery case sealing device further comprising a lower sealing roller coupled to the lower heat bar.
The method of claim 5, wherein the lower sealing roller,

A battery case sealing device that moves the surface of the sealing portion from one end of the sealing portion to the other end of the sealing portion simultaneously with the upper sealing roller.
The method of claim 5, wherein the lower sealing roller,

While the upper sealing roller moves the surface of the sealing part in the direction from one end of the sealing part to the other end of the sealing part, the battery case sealing device moves the surface of the sealing part in the direction from the other end of the sealing part to one end of the sealing part.
The method of claim 5, wherein the lower sealing roller,

a lower sealing roller fastening portion coupled to the lower heat bar and moving in a direction from one end of the sealing portion to the other end of the sealing portion while coupled to the lower heat bar; and

A lower sealing wheel that is coupled to the lower sealing roller fastening part and moves on the surface of the sealing part as the lower sealing roller fastening part moves from one end of the sealing part to the other end of the sealing part.
The method of claim 8, wherein the lower sealing wheel is:

A battery case sealing device included in the upper sealing roller and having a different shape from an upper sealing wheel corresponding to the lower sealing wheel.
The method of claim 8, wherein the lower sealing wheel is:

A battery case sealing device in which an upper sealing wheel included in the upper sealing roller and corresponding to the lower sealing wheel has a different surface area in contact with the sealing portion.
In the method of sealing a pouch-type battery case accommodating an electrode assembly,

providing heat energy to a lower portion of the sealing portion including at least one corner among a plurality of corners of the pouch-type battery case;

providing heat energy to an upper sealing roller disposed on the upper part of the sealing part and in contact with the upper surface of the sealing part; and

A battery case sealing method comprising: moving the sealing roller on a surface of the sealing portion from one end of the sealing portion to the other end of the sealing portion.
According to claim 11,

A battery case sealing method further comprising providing heat energy to a lower sealing roller disposed below the sealing part and in contact with a lower surface of the sealing part.
According to clause 12,

A method of sealing a battery case further comprising: moving the lower sealing roller on the surface of the sealing portion in a direction from one end of the sealing portion to the other end of the sealing portion simultaneously with the upper sealing roller.
According to clause 12,

The battery further comprising: moving the upper sealing roller on the surface of the sealing part from one end of the sealing part to the other end of the sealing part, and then moving the lower sealing roller from one end of the sealing part to the other end of the sealing part. Case sealing method.