CN218939968U - A packaging liquid injection structure for soft-packed batteries - Google Patents

Abstract

The utility model provides a packaging liquid injection structure of a soft-packed battery cell. The packaging liquid injection structure of the soft-packed battery cell includes a packaging bag; a core bag and an air bag area are arranged inside the packaging bag; A liquid accommodating cavity; a weakening component is arranged on the electrolyte accommodating cavity. The utility model provides a new type of liquid injection method for the soft-packed battery cell by setting the electrolyte accommodating cavity at the air bag area, that is, the squeeze-type liquid injection in the soft pack, which isolates the contact between the electrolyte and the air. This simplifies the process of battery cell injection and reduces the production cost.

Description

A packaging liquid injection structure for soft-packed batteries

technical field

The utility model belongs to the technical field of packaging liquid injection technology for soft-packaged electric cores, and relates to a liquid-injection structure for packaging soft-packaged electric cores.

Background technique

The liquid injection steps of the existing soft-pack structure lithium-ion battery include: weighing before liquid injection, recording the weight data, and uploading to the system; opening the battery cell, pouring a certain amount of electrolyte; weighing after liquid injection, recording the weight data, Uploading system; standing in vacuum, so that the electrolyte can quickly penetrate into the inside of the core bag; sealing the air bag to prevent the electrolyte from flowing out; standing at room temperature, so that the electrolyte can fully infiltrate the inside of the core bag.

However, the following problems have not been solved based on the existing liquid injection technology:

The existing process is easy to cause the appearance of the cell to be polluted, and additional protection is required. In the process of cell injection and transfer, a small amount of liquid will inevitably splash and overflow, which will corrode the surface of the aluminum-plastic film and cause poor appearance. In severe cases, it needs to be scrapped.

In addition, the liquid injection accuracy in the existing process is greatly affected by the equipment capability and reliability, including the accuracy of the weighing system, the measurement accuracy of the liquid injection pump, and the ability to maintain accuracy in the case of long-term operation, abnormal shutdown or model change. . When the accuracy of liquid injection fluctuates greatly, the consistency of electrical properties will be affected accordingly.

Therefore, providing a simple and convenient liquid injection process with easy-to-control liquid injection accuracy is a technical problem that needs to be solved urgently in the field of soft-pack battery manufacturing technology.

Utility model content

Aiming at the deficiencies of the existing technology, the purpose of this utility model is to provide a soft package battery and its packaging liquid injection structure. By setting an electrolyte accommodating cavity at the airbag area, a soft package battery is provided. The liquid injection method, that is, the extrusion type liquid injection in the soft bag, isolates the contact between the electrolyte and the air, simplifies the process of cell liquid injection, and reduces the production cost.

For this purpose, the utility model adopts the following technical solutions:

The utility model provides a liquid injection structure for encapsulating soft-packed electric cores. The liquid-injecting structure for encapsulating soft-enclosed electric cores includes an encapsulating bag; inside the encapsulating bag is provided a core bag and an air bag area;

The airbag area is provided with an electrolyte accommodating cavity;

A weakening component is arranged on the electrolyte accommodating cavity.

Preferably, the electrolyte accommodating cavity is a cavity resistant to electrolyte corrosion.

Preferably, the electrolyte accommodating cavity is a polypropylene (Polypropylene, PP) cavity or a polyester resin (Polyethylene terephthalate, PET) cavity.

Preferably, the wall thickness of the electrolyte accommodating cavity is 0.02-3 mm.

Preferably, the weakening component is arranged on a side of the electrolyte accommodating cavity facing the battery cell.

Preferably, the weakening component includes a plurality of score lines arranged along the length direction of the electrolyte accommodating cavity.

Preferably, the width of each score line is 0.2-3mm, and the length of each score line is 0.5-8mm.

Preferably, the quality of the electrolyte in the electrolyte accommodating cavity is consistent with the quality of the liquid injected into the soft pack cell.

Preferably, the packaging bag includes an aluminum-plastic film packaging bag.

Preferably, the electrolyte accommodating cavity is cylindrical.

Preferably, the electrolyte accommodating cavity has a circular or elliptical cross section.

By the above technical scheme, the beneficial effects of the utility model are as follows:

In the utility model, an electrolyte accommodating cavity is provided at the airbag area, and a weakening part is arranged on the electrolyte accommodating cavity. When pressure is applied to the weakened part on the electrolyte accommodating cavity, the weakening part breaks, The electrolyte flows out from the electrolyte containing cavity, and gradually diffuses and fills the entire soft-packed battery cell, realizing squeeze-type liquid injection, thereby isolating the contact between the electrolyte solution and the air, simplifying the process of cell liquid injection, and reducing the The production cost is reduced; moreover, the liquid injection can also improve the injection accuracy and the consistency of the electrolyte injection.

Description of drawings

Fig. 1 is a structural schematic diagram of the packaging liquid injection structure of the pouch cell provided by the present invention.

Fig. 2 is a schematic diagram of the liquid injection process of the soft-pack battery provided by the utility model.

in:

1-Encapsulation bag, 2-Cell package, 3-Air bag area, 4-Electrolyte solution chamber, 5-Sealing area, 6-Cell top, 7-Cell bottom, 8-Pressure direction, 9-Electrolysis direction of liquid flow.

Detailed ways

It should be understood that, in the description of the present invention, the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", The orientations or positional relationships indicated by "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention. Novel and simplified descriptions do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as limiting the utility model.

It should be noted that, in the description of the present utility model, unless otherwise clearly stipulated and limited, the terms "setting", "connecting" and "connecting" should be understood in a broad sense, for example, it can be a fixed connection or a flexible connection. Detachable connection, or integral connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention through specific situations.

The utility model provides a liquid injection structure for encapsulating soft-packed electric cores. The liquid-injecting structure for encapsulating soft-enclosed electric cores includes an encapsulating bag; inside the encapsulating bag is provided a core bag and an air bag area;

The airbag area is provided with an electrolyte accommodating cavity;

A weakening component is arranged on the electrolyte accommodating cavity.

In the utility model, an electrolyte accommodating cavity is provided at the airbag area, and a weakening part is arranged on the electrolyte accommodating cavity. When pressure is applied to the weakened part on the electrolyte accommodating cavity, the weakening part breaks, The electrolyte flows out from the electrolyte containing cavity, and gradually diffuses and fills the entire soft-packed battery cell, realizing squeeze-type liquid injection, thereby isolating the contact between the electrolyte solution and the air, simplifying the process of cell liquid injection, and reducing the The production cost is reduced; moreover, the liquid injection can also improve the electrolyte injection accuracy and electrolyte injection consistency.

As a preferred solution provided by the present invention, the electrolyte accommodating cavity is obtained by the following method:

After the electrolyte is filled in the open liquid injection cavity, the liquid injection cavity is sealed and separated into an independent electrolyte storage cavity by means of heat sealing or ultrasonic composite, and the two sides of the electrolyte storage cavity The end is the sealing area, and the sealing area is packaged together with the top, bottom and packaging bag of the pouch cell.

In one embodiment, the electrolyte accommodating cavity is a cavity resistant to electrolyte corrosion.

In one embodiment, the electrolyte accommodating cavity includes a PP cavity or a PET cavity.

In one embodiment, the wall thickness of the electrolyte accommodating cavity is 0.02-3mm, such as 0.02mm, 0.05mm, 0.1mm, 1mm, 2mm or 3mm, but not limited to the listed values, other values within the range Values not listed also apply.

In one embodiment, the weakening component is arranged on a side of the electrolyte accommodating cavity facing the core pack.

When the weakened part on the side of the electrolyte containing cavity facing the core package breaks, the electrolyte flowing out of the electrolyte containing cavity first flows to the core package and directly infiltrates the positive and negative electrodes in the core package, realizing rapid liquid injection , as more electrolyte flows out, the electrolyte gradually diffuses and fills the entire soft core pack, thereby improving the injection efficiency.

In one embodiment, the weakening component includes a plurality of scoring lines arranged along the length direction of the electrolyte accommodating cavity.

In one embodiment, the width of each of the scribed lines is 0.2-3mm, for example, it can be 0.2mm, 0.5mm, 1mm, 1.5mm, 2mm or 3mm, but not limited to the enumerated values, other values not within the range The listed values also apply.

In one embodiment, the length of each said score line is 0.5-8mm, for example, it can be 0.5mm, 1mm, 2mm, 5mm, 7mm or 8mm, but it is not limited to the enumerated numerical value, and other unlisted values within the numerical range Numerical values also apply.

In one embodiment, the quality of the electrolyte in the electrolyte accommodating cavity is consistent with the quality of the liquid injected into the soft-packed battery cell.

In the utility model, the quality of the electrolyte in the electrolyte storage cavity is the amount of liquid injection required for the soft-packed battery cell, and the quality of the electrolyte in the electrolyte storage cavity can be measured as a detection item in the battery preparation process The liquid injection volume is stable and controllable, and the liquid injection volume is not affected by the accuracy and reliability of the equipment, thereby improving the stability and reliability of the liquid injection accuracy and improving the consistency of the battery cells.

In one embodiment, the packaging bag is an aluminum-plastic film packaging bag.

In one embodiment, the electrolyte accommodating cavity is cylindrical.

In one embodiment, the electrolyte accommodating cavity has a circular or elliptical cross section.

The utility model provides an encapsulation liquid injection process of the above-mentioned soft package cell encapsulation liquid injection structure, and the encapsulation liquid injection process includes the following steps:

(1) After the electrolyte accommodating cavity is arranged in the air bag area, it is packaged together with the core package;

(2) Applying pressure to the airbag area, weakening the rupture of the component, and injecting liquid to complete the encapsulation liquid injection process.

The packaging liquid injection process of the utility model is different from the external open liquid injection and then packaging in the prior art. The electrolyte containing cavity filled with electrolyte is first packaged with the battery core, and then the electrolytic solution is squeezed by external force. The liquid accommodating cavity is broken, and the electrolyte is released from the electrolyte accommodating cavity, flows out and infiltrates into the entire battery core, thereby completing the liquid injection.

The packaging liquid injection process of the utility model simplifies the investment of liquid injection equipment, reduces the use of production space, and greatly reduces the cost of production operation and construction. At the same time, there is no need to do additional protection for the appearance of the battery cell, and the use of PET protective film is eliminated. In addition, the liquid injection accuracy does not depend on the equipment accuracy and reliability, and the liquid injection accuracy is stable and controllable, thereby improving the consistency of the battery cells.

The technical scheme of the utility model will be further described below in conjunction with the accompanying drawings and through specific embodiments.

Example 1

This embodiment provides a packaging liquid injection structure of a soft-packed battery cell and a packaging liquid injection process.

The packaging liquid injection structure ( FIG. 1 ) includes a packaging bag 1 ; a core bag 2 and an airbag area 3 are arranged inside the packaging bag 1 , and the airbag area 3 is provided with an electrolyte accommodating cavity 4 . The packaging bag 1 is an aluminum-plastic film, and the electrolyte accommodating cavity 4 is cylindrical with a circular cross section. The electrolyte accommodating cavity 4 is a soft cavity made of PP (Sinopec, P8101), and the wall thickness is 1.5mm. The electrolyte accommodating cavity 4 is provided with a weakening component, and the weakening component Set on the side of the electrolyte accommodating cavity 4 facing the core pack 2, the weakening component is a plurality of score lines arranged along the length direction of the electrolyte accommodating cavity 4, and the length of each score line is It is 4mm and the width is 1.5mm. The inside of the electrolyte accommodating cavity 4 is electrolyte, and the quality of the electrolyte is consistent with the injection quality of the soft pack cell.

As shown in Figure 2, when pressure is applied to the airbag area 3, the weakened component is broken under the pressure of the direction 8, and the electrolyte in the electrolyte accommodating cavity 4 flows to the battery cell according to the direction 9, realizing soft The process of extruding and injecting liquid in the bag.

Example 2

This embodiment provides a packaging liquid injection structure of a soft-packed battery cell and a packaging liquid injection process.

The packaging liquid injection structure ( FIG. 1 ) includes a packaging bag 1 ; a core bag 2 and an airbag area 3 are arranged inside the packaging bag 1 , and the airbag area 3 is provided with an electrolyte accommodating cavity 4 . The packaging bag 1 is an aluminum-plastic film, and the electrolyte accommodating cavity 4 is cylindrical with a circular cross section. The electrolyte accommodating cavity 4 is a soft cavity made of PET (Fulin Plastic, FR530) with a wall thickness of 0.02mm. The electrolyte accommodating cavity 4 is provided with a weakening component, and the weakening The component is arranged on the side of the electrolyte accommodating cavity 4 facing the core pack 2, and the weakening component is a plurality of scribed lines arranged along the length direction of the electrolyte accommodating cavity 4, each of the scribed lines The length is 0.5mm and the width is 0.2mm. The inside of the electrolyte accommodating cavity 4 is electrolyte, and the quality of the electrolyte is consistent with the injection quality of the soft pack cell.

As shown in Figure 2, when pressure is applied to the airbag area 3, the weakened component is broken under the pressure of the direction 8, and the electrolyte in the electrolyte accommodating cavity 4 flows to the battery cell according to the direction 9, realizing soft The process of extruding and injecting liquid in the bag.

Example 3

This embodiment provides a packaging liquid injection structure of a soft-packed battery cell and a packaging liquid injection process.

The packaging liquid injection structure ( FIG. 1 ) includes a packaging bag 1 ; a core bag 2 and an airbag area 3 are arranged inside the packaging bag 1 , and the airbag area 3 is provided with an electrolyte accommodating cavity 4 . The packaging bag 1 is an aluminum-plastic film, and the electrolyte accommodating cavity 4 is cylindrical with a circular cross section. The electrolyte accommodating cavity 4 is a soft cavity made of PP (Sinopec, P8101) with a wall thickness of 3mm. The electrolyte accommodating cavity 4 is provided with a weakening component, and the weakening component is set On the side of the electrolyte accommodating cavity 4 facing the core pack 2, the weakening component is a plurality of scribed lines arranged along the length direction of the electrolyte accommodating cavity 4, and the length of each of the scribed lines is 8mm, width 3mm. The inside of the electrolyte accommodating cavity 4 is electrolyte, and the quality of the electrolyte is consistent with the injection quality of the soft pack cell.

As shown in Figure 2, when pressure is applied to the airbag area 3, the weakened component is broken under the pressure of the direction 8, and the electrolyte in the electrolyte accommodating cavity 4 flows to the battery cell according to the direction 9, realizing soft The process of extruding and injecting liquid in the bag.

Example 4

This embodiment provides a packaging liquid injection structure and packaging liquid injection process for soft-packed batteries. The only difference from Embodiment 1 is that the wall thickness of the electrolyte accommodating cavity is 0.015 mm.

In this embodiment, the wall thickness is less than 0.02 mm, and the sealing performance of the cavity for the electrolyte solution is reduced, which may easily lead to leakage of the electrolyte solution.

Example 5

This embodiment provides a packaging liquid injection structure and packaging liquid injection process for soft-packed batteries. The only difference from Embodiment 1 is that the wall thickness of the electrolyte accommodating cavity is 3.2 mm.

In this embodiment, the wall thickness is greater than 3mm, and the flexibility of the electrolyte containing cavity is reduced. After the extrusion action, there will still be a lot of electrolyte remaining in the cavity, which cannot enter the inside of the cell, and affects the liquid injection effect.

Usually ±0.5g is an acceptable injection accuracy.

Comparative example 1

This comparative example provides a packaging liquid injection structure of a soft-packed battery cell and a packaging liquid injection process.

The difference between the encapsulation liquid injection structure and the embodiment 1 is that there is no electrolyte accommodating cavity in the airbag area.

The encapsulation injection process includes the following steps:

(1) Weigh before liquid injection, record the weight data, and upload to the system;

(2) Open the battery cell and fill it with a certain amount of electrolyte;

(3) Weigh after liquid injection, record the weight data, and upload to the system;

(4) Vacuum standing, so that the electrolyte quickly penetrates into the core bag;

(5) The air bag is sealed to prevent the electrolyte from flowing out;

(6) Stand at room temperature so that the electrolyte fully infiltrates the inside of the core pack.

The appearance of the cells in this comparative example is easily polluted, and additional protection is required in the future. It is inevitable that a small amount of liquid will splash and overflow during the process of cell injection and transfer, which will corrode the surface of the aluminum-plastic film and cause poor appearance. In severe cases, it needs to be scrapped.

In this comparison, the liquid injection accuracy is greatly affected by the equipment capability and reliability, including the accuracy of the weighing system, the measurement accuracy of the liquid injection pump, and the ability to maintain accuracy under long-term operation, abnormal shutdown, and model change. When the liquid accuracy fluctuates greatly, the consistency of electrical properties will be affected.

The above is only a specific embodiment of the present utility model, but the scope of protection of the present utility model is not limited thereto, and those skilled in the art should understand that any technical personnel belonging to the technical field can use the technology disclosed in the present utility model Within the scope, easily conceivable changes or substitutions all fall within the protection scope and disclosure scope of the present utility model.

Claims (10)

1. The packaging and liquid injection structure of the soft package battery core is characterized by comprising a packaging bag; the inside of the packaging bag is provided with a core bag and an air bag area;

the air bag area is provided with an electrolyte accommodating cavity;

and a weakening component is arranged on the electrolyte accommodating cavity.

2. The package electrolyte injection structure of the soft-package battery cell of claim 1, wherein the electrolyte containing cavity is an electrolyte corrosion resistant cavity.

3. The packaging and liquid injecting structure of the soft-packaged battery cell according to claim 1, wherein the electrolyte accommodating cavity is a PP cavity or a PET cavity.

4. The packaging and liquid injecting structure of the soft-packaged battery cell according to claim 1, wherein the wall thickness of the electrolyte accommodating cavity is 0.02-3 mm.

5. The encapsulated electrolyte fill structure of claim 1 wherein said attenuation member is disposed on a side of said electrolyte receiving cavity facing said core pack.

6. The encapsulated electrolyte fill structure of claim 1 wherein the attenuation member comprises a plurality of score lines disposed along a length of the electrolyte receiving cavity.

7. The package liquid injection structure of the soft package battery cell according to claim 6, wherein the width of each scribing line is 0.2-3 mm; the length of each scribing line is 0.5-8 mm.

8. The encapsulated electrolyte injection structure of the soft-packaged battery cell according to claim 1, wherein the mass of the electrolyte in the electrolyte accommodating cavity is consistent with the injection mass of the soft-packaged battery cell.

9. The encapsulated electrolyte injection structure of a soft-pack cell of claim 1, wherein the electrolyte receiving cavity is cylindrical.

10. The encapsulated electrolyte injection structure of a soft-pack cell of claim 1, wherein the electrolyte receiving cavity has a circular or oval cross section.

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