Soft package battery packaging process and soft package battery

Abstract

The invention belongs to the technical field of battery manufacturing, and particularly relates to a soft package battery packaging technology and a soft package battery, the soft package battery packaging technology comprises the steps that a soft package battery semi-finished product is taken, the soft package battery semi-finished product comprises a packaging film and a battery cell in the packaging film, the packaging film comprises a main body area, a side sealing area and a top sealing area, and the top sealing area comprises a sealing area and an inner unsealed area; the inner unsealed area is arranged on one side close to the main body area; hot-pressing sealing is conducted on the sealing area through the widened top sealing head, and the PP layer in the sealing area is extruded outwards to form an overflow area; and cutting off the overflow area to form a top sealing area, and then manufacturing the soft package battery semi-finished product into the soft package battery. An original outer unsealed area is removed, a widened top sealing head is used for directly carrying out hot-pressing sealing on a sealing area, a molten PP layer in the sealing area is extruded out, and laser is used for cutting, so that the length of a battery main body is increased, and the capacity and the energy density of the battery are improved; the sealing head is widened, the heat conduction performance is improved, the packaging reliability is improved, an outer unsealed area does not need to be controlled, and the packaging debugging efficiency is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery manufacturing, and in particular relates to a soft-pack battery packaging process and a soft-pack battery. Background Art

[0002] With the development of new energy vehicles, energy storage systems, and mobile devices, the soft-pack lithium-ion battery pack industry is showing a trend of sustained growth worldwide. Soft-pack lithium-ion batteries generally require three packaging processes: top sealing, side sealing, and secondary sealing. The top seal has a very obvious effect on the length of the battery. At present, the length of a conventional soft-pack lithium battery is: the length of the battery body + the inner unsealed area + the sealing area + the outer unsealed area. When the soft-pack battery is packaged, the heat conducted by the high-temperature head will cause the PP layers in the aluminum-plastic film on both sides to fuse together, ensuring that the battery is fixed in the aluminum-plastic film. During the PP fusion process of the aluminum-plastic film, the PP is squeezed by the head and extended to both sides, and the inner unsealed area and the outer unsealed area respectively receive the extended PP layer. Among them, the existence of the outer unsealed area seriously affects the improvement of battery capacity and capacity density. If the outer unsealed area of ​​the aluminum-plastic film is not retained, the aluminum-plastic film PP extruded by the head during packaging will also affect the length of the battery cell. Summary of the invention

[0003] The purpose of the present invention is to provide a soft-pack battery packaging process and a soft-pack battery in view of the shortcomings of the prior art. By not retaining the outer unsealed area of ​​the packaging film and cutting off the aluminum-plastic film PP layer extruded during packaging, the length of the battery body can be increased simultaneously, thereby improving the capacity and energy density of the battery, and improving the packaging reliability and packaging debugging efficiency.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A soft pack battery packaging process, comprising the following steps:

[0006] Step 1: Take a semi-finished soft-pack battery, the semi-finished soft-pack battery includes a packaging film and a battery cell, wherein the packaging film includes a main body area, a side sealing area and a top sealing area, the battery cell is accommodated in the main body area, the top sealing area is located above the main body area, the top sealing area includes a sealing area and an inner unsealed area, the inner unsealed area is arranged on a side of the sealing area close to the main body area, and the battery cell is provided with a pole ear, and the pole ear passes through the top sealing area;

[0007] Step 2, hot-pressing and sealing the sealing area through the top sealing head, the aluminum-plastic film PP layer in the sealing area is melted and bonded, and squeezed to both sides, entering the inner unsealed area inwardly, and being squeezed out of the sealing area outwardly to form an overflow area; and then hot-pressing and sealing the side sealing area;

[0008] Step 3, cutting off the overflow area to form a complete top sealing area, and then making the soft-pack battery semi-finished product into a soft-pack battery.

[0009] Preferably, the length of the top sealing area is D, the length of the sealing area is B, and the length of the inner unsealed area is C, satisfying the following relationship: B+C=D.

[0010] Preferably, the width of the top seal head is A, satisfying the following relationship: AB≥0.

[0011] Preferably, the length of the overflow area is F, satisfying the following relationship: B+F≥A.

[0012] Preferably, the tab is provided with tab glue, and the tab glue is provided between the tab and the packaging film.

[0013] Preferably, the tab glue partially protrudes out of the top sealing area.

[0014] Preferably, in step 3, laser cutting is used to simultaneously remove the overflow area and the tab glue protruding from the sealing area, leaving the tab portion.

[0015] A soft-pack battery is made according to any of the above-mentioned packaging processes, comprising a packaging film and a battery cell coated in the packaging film, wherein the packaging film forms side seals and top seals after coating the battery cell, the top seal is located above the battery cell, the side seals are located on the sides of the battery cell, and the battery cell is provided with a pole ear, which passes through the top seal.

[0016] Preferably, the packaging film is an aluminum-plastic film, which includes a nylon layer, an Al layer and a PP layer from the outside to the inside, and the tabs are provided with tab glue, and the tab glue and the PP layer are bonded to each other.

[0017] Preferably, the packaging film further includes two edge seals, which are arranged on the other side parallel to and opposite to the side edge seals, and the side edge seals, the top edge seals and the second edge seals are sequentially connected end to end to encapsulate the battery cell in the packaging film.

[0018] Compared with the prior art, the beneficial effects of the present invention are: by removing the original external unsealed area, using the widened top seal head to directly perform hot pressure sealing on the sealing area, and squeezing out the melted PP layer in the sealing area, and then using laser cutting to increase the length of the battery body, thereby improving the capacity and energy density of the battery; the head is widened, the thermal conductivity is improved, the packaging reliability is improved, there is no need to control the external unsealed area, and the packaging debugging efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of an embodiment of the present invention before packaging process.

[0020] Figure 2 It is a schematic diagram of the structure after the packaging process of an embodiment of the present invention.

[0021] Figure 3 It is a schematic diagram of the structure of a soft-pack battery according to an embodiment of the present invention.

[0022] Reference numerals:

[0023] 1. Packaging film, 11. Main body area, 12. Side sealing area, 13. Top sealing area, 14. Sealing area, 15. Inner unsealed area, 16. Overflow area;

[0024] 100, battery cell, 101, tab, 102, tab glue, 103, side edge sealing, 104, top edge sealing, 105, second edge sealing;

[0025] 200. Top seal. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] like Figure 1-3 As shown, this embodiment provides a soft-pack battery packaging process and a soft-pack battery.

[0028] A soft pack battery packaging process, comprising the following steps:

[0029] Step 1: Take a semi-finished soft-pack battery, which includes a packaging film 1 and a battery cell 100, wherein the packaging film 1 includes a main body area 11, a side sealing area 12 and a top sealing area 13, the battery cell 100 is accommodated in the main body area 11, the top sealing area 13 is located above the main body area 11, the top sealing area 13 includes a sealing area 14 and an inner unsealed area 15, the inner unsealed area 15 is arranged on the side of the sealing area 14 close to the main body area 11, and a pole ear 101 is arranged on the battery cell 100, and the pole ear 101 passes through the top sealing area 13; a receiving bag is provided in the main body area 11, and the battery cell 100 is arranged in the receiving bag and is covered by the packaging film 1 from top to bottom;

[0030] Step 2, hot-pressing and sealing the sealing area 14 through the top sealing head 200, the aluminum-plastic film PP layer in the sealing area 14 is melted and bonded, and squeezed to both sides, entering the inner unsealed area 15 inwardly, and being squeezed out of the sealing area 14 outwardly to form an overflow area 16; then hot-pressing and sealing the side sealing area 12, and hot-pressing and sealing the side sealing area 12 and the top sealing area 13 respectively, so that the battery cell 100 is wrapped in the packaging film 1, so as to facilitate the subsequent liquid injection operation;

[0031] Step 3, cutting off the overflow area 16 to form a complete top sealing area 13, and then making the soft-pack battery semi-finished product into a soft-pack battery.

[0032] The overall length of the soft pack battery is L, and its length direction is the axial direction extending along the tab 101. The length of the battery cell 100 is L1.

[0033] Furthermore, the length of the top sealing area 13 is D, the length of the sealing area 14 is B, and the length of the inner unsealed area 15 is C, which satisfies the following relationship: B+C=D. The length L1 of the battery cell 100 plus the length D of the top sealing area 13 is determined as the overall battery length, and the thickness of the lower part of the battery cell 100 that is in direct contact with the packaging film 1 is negligible.

[0034] Furthermore, the width of the top seal head 200 is A, which satisfies the following relationship: AB ≥ 0. The width A of the top seal head 200 used in this embodiment is greater than or equal to the length B of the sealing area 14, so as to meet the requirement of sealing the entire sealing area 14, and after the packaging film 1 is hot-pressed and sealed, the melted PP layer in the packaging film 1 is squeezed out of the sealing area 14 to form an overflow area 16.

[0035] Furthermore, the length of the overflow area 16 is F, which satisfies the following relationship: B+F≥A. After the top sealing head 200 used in this embodiment is pressed tightly against the sealing area 14 of the packaging film 1, the PP layer inside the packaging film 1 melts to form the overflow area 16, which should also fill the pressing gap between the sealing area 14 and the top sealing head 200 to ensure that the top sealing area 13 can form a good closed environment.

[0036] like Figure 1 As shown, the length of the top sealing head 200 is slightly shorter than the sealing area 14 to facilitate the display of its packaging position. In fact, during the production process, the top sealing head 200 completely covers the sealing area 14 to achieve complete coverage and hot pressing sealing.

[0037] Furthermore, the tab 101 is provided with a tab glue 102, which is provided between the tab 101 and the packaging film 1. When the top sealing head 200 performs heat-pressing sealing on the packaging film 1, the tab 101 is fixed on the packaging film 1 by the tab glue 102.

[0038] Furthermore, part of the tab glue 102 protrudes from the top sealing area 13. The protruding tab glue 102 can ensure that there is no direct contact between the tab 101 and the packaging film 1, thereby maintaining stable performance of the battery.

[0039] Furthermore, in step 3, laser cutting is used to simultaneously remove the overflow area 16 and the tab glue 102 protruding from the sealing area 14, leaving the tab 101. After hot pressing and sealing, after the melted PP layer of the overflow area 16 and the tab glue 102 are bonded and fixed to form, they are removed by laser cutting or other methods to obtain a complete top sealing area 13 and the tab 101 passing through the top sealing area 13.

[0040] A soft-pack battery is manufactured according to the above-mentioned packaging process, comprising a packaging film 1 and a battery cell 100 coated in the packaging film 1. After the packaging film 1 coats the battery cell 100, a side sealing edge 103 and a top sealing edge 104 are formed. The top sealing edge 104 is located above the battery cell 100, and the side sealing edge 103 is located on the side of the battery cell 100. The battery cell 100 is provided with a pole ear 101, and the pole ear 101 passes through the top sealing edge 104.

[0041] Furthermore, the packaging film 1 is an aluminum-plastic film, which includes a nylon layer, an Al layer and a PP layer from the outside to the inside. The tab 101 is provided with a tab glue 102, and the tab glue 102 and the PP layer are bonded to each other.

[0042] Furthermore, the packaging film 1 also includes two sealing edges 105, which are arranged on the other side parallel to the side sealing edge 103. The side sealing edge 103, the top sealing edge 104 and the second sealing edge 105 are sequentially connected end to end to cover the battery cell 100 in the packaging film 1.

[0043] According to the disclosure and teaching of the above description, those skilled in the art to which the present invention belongs can also change and modify the above embodiment. Therefore, the present invention is not limited to the above specific embodiment, and any obvious improvement, replacement or modification made by those skilled in the art on the basis of the present invention belongs to the protection scope of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the present invention.

Claims

1. A soft pack battery packaging process, characterized in that: Follow these steps: Step 1: Take a semi-finished soft-pack battery, the semi-finished soft-pack battery includes a packaging film and a battery cell, wherein the packaging film includes a main body area, a side sealing area and a top sealing area, the battery cell is accommodated in the main body area, the top sealing area is located above the main body area, the top sealing area includes a sealing area and an inner unsealed area, the inner unsealed area is arranged on a side of the sealing area close to the main body area, and the battery cell is provided with a pole ear, and the pole ear passes through the top sealing area; Step 2, hot-pressing and sealing the sealing area through the top sealing head, the aluminum-plastic film PP layer in the sealing area is melted and bonded, and squeezed to both sides, entering the inner unsealed area inwardly, and being squeezed out of the sealing area outwardly to form an overflow area; and then hot-pressing and sealing the side sealing area; Step 3, cutting off the overflow area to form a complete top sealing area, and then making the soft-pack battery semi-finished product into a soft-pack battery.

2. The soft pack battery packaging process according to claim 1, characterized in that: The length of the top sealing area is D, the length of the sealing area is B, and the length of the inner unsealed area is C, satisfying the following relationship: B+C=D.

3. The soft pack battery packaging process according to claim 2, characterized in that: The width of the top seal head is A, which satisfies the following relationship: AB≥0.

4. The soft pack battery packaging process according to claim 3, characterized in that: The length of the overflow area is F, which satisfies the following relationship: B+F≥A.

5. The soft pack battery packaging process according to claim 1, characterized in that: The tab is provided with tab glue, and the tab glue is arranged between the tab and the packaging film.

6. The soft pack battery packaging process according to claim 5, characterized in that: The ear glue partially protrudes from the top sealing area.

7. The soft pack battery packaging process according to claim 6, characterized in that: In step 3, laser cutting is performed to simultaneously remove the overflow area and the tab glue protruding from the sealing area, leaving the tab portion.

8. A soft pack battery, prepared according to any one of claims 1 to 7, characterized in that: It includes a packaging film and a battery cell wrapped in the packaging film. After the packaging film covers the battery cell, side sealing edges and top sealing edges are formed. The top sealing edge is located above the battery cell, and the side sealing edge is located on the side of the battery cell. The battery cell is provided with a pole ear, and the pole ear passes through the top sealing edge.

9. The soft pack battery according to claim 8, characterized in that: The packaging film is an aluminum-plastic film, which includes a nylon layer, an Al layer and a PP layer from the outside to the inside. The tabs are provided with tab glue, and the tab glue and the PP layer are bonded to each other.

10. The soft pack battery according to claim 9, characterized in that: The packaging film also includes two edge seals, which are arranged on the other side parallel to and opposite to the side edge seals. The side edge seals, the top edge seals and the second edge seals are sequentially connected end to end to wrap the battery cell in the packaging film.

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