Battery cell packaging structure

Abstract

The utility model belongs to battery technical field especially relates to a kind of electric core packaging structure, including electric core, first encapsulation, second encapsulation and fluid medium, first encapsulation is encapsulated in the outer surface of electric core;Second encapsulation is encapsulated outside first encapsulation, and accommodating cavity is formed between second encapsulation and first encapsulation;Fluid medium is filled in accommodating cavity.Second encapsulation and first encapsulation form the accommodating cavity of airtight, and fluid medium is filled in the accommodating cavity of airtight, based on isostatic pressure pascal law, that is, in the fluid medium in airtight container, pressure can be evenly transmitted to each direction of airtight container, so that when using clamp to pressurize electric core packaging structure, the pressure of clamp can be evenly transmitted to each direction of accommodating cavity, so that the pressure that electric core is subjected to in each direction is consistent, effectively solve the problem that electric core is unevenly stressed under the pressure of clamp in prior art, realize the densification of electric core.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a cell packaging structure. Background Technology

[0002] Due to the characteristics of batteries, the volume expansion of batteries during cycling requires external high pressure to restrain it. In related technologies, clamps are used to pressurize the battery cells. The clamps generally include two clamps, which are usually distributed on both sides of the battery cell. The two clamps can only apply pressure to the battery cell in one direction. Under the action of high pressure, the battery cell is easily squeezed and deformed in other directions, resulting in uneven stress on the battery cell and failing to achieve cell densification. Utility Model Content

[0003] The purpose of this invention is to provide a battery cell packaging structure that enables the pressure of the clamp to be evenly transmitted to all directions of the receiving cavity, ensuring that the battery cell is subjected to consistent pressure in all directions, thereby achieving cell densification.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] The battery cell packaging structure includes:

[0006] Battery cell;

[0007] The first package is encapsulated on the outer surface of the battery cell;

[0008] A second package is encapsulated outside the first package, and a receiving cavity is formed between the second package and the first package;

[0009] A fluid medium is filled into the cavity.

[0010] The beneficial effects of this utility model are:

[0011] The battery cell packaging structure provided in this embodiment of the utility model forms a sealed cavity between the second packaging body and the first packaging body, and fills the sealed cavity with a fluid medium. Based on Pascal's law of isostatic pressure, that is, in the fluid medium in the sealed container, the pressure can be uniformly transmitted to all directions of the sealed container. Therefore, when the battery cell packaging structure is pressurized by a clamp, the pressure of the clamp can be uniformly transmitted to all directions of the cavity, so that the pressure on the battery cell is consistent in all directions. This effectively solves the problem of uneven force on the battery cell under clamp pressure in the prior art and realizes the densification of the battery cell. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the battery cell packaging structure provided in one embodiment of the present invention;

[0013] Figure 2 This is a schematic diagram of the battery cell packaging structure provided in another embodiment of the present invention.

[0014] In the picture:

[0015] 10. Battery cell; 11. First tab; 12. Second tab; 20. First package; 30. Second package; 40. Receiving cavity; 50. Adhesive layer. Detailed Implementation

[0016] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0017] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0018] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0019] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0020] like Figure 1 and Figure 2As shown, this utility model embodiment provides a battery cell packaging structure, including a battery cell 10, a first packaging body 20, a second packaging body 30, and a fluid medium. The first packaging body 20 is packaged on the outer surface of the battery cell 10; the second packaging body 30 is packaged outside the first packaging body 20, and a receiving cavity 40 is formed between the second packaging body 30 and the first packaging body 20; the fluid medium is filled in the receiving cavity 40. The second packaging body 30 and the first packaging body 20 form a closed receiving cavity 40, and the closed receiving cavity 40 is filled with a fluid medium. Based on Pascal's law of isostatic pressure, that is, in the fluid medium in the closed container, the pressure can be uniformly transmitted to all directions of the closed container. Therefore, when the battery cell packaging structure is pressurized by a clamp, the pressure of the clamp can be uniformly transmitted to all directions of the receiving cavity 40, so that the pressure on the battery cell 10 is consistent in all directions. This effectively solves the problem of uneven force on the battery cell 10 under clamp pressure in the prior art, and realizes the densification of the battery cell 10.

[0021] The battery cell 10 has a first tab 11 and a second tab 12 with opposite polarities. A portion of the first tab 11 and the second tab 12 is connected to the first package 20, while the other portion is located outside the first package 20 and connected to the second package 30. This arrangement ensures that the first tab 11 and the second tab 12 do not affect the encapsulation of the first package 20 and the second package 30, while also enhancing the sealing performance of the first package 20 and the second package 30. In some embodiments, the first tab 11 and the second tab 12 are located on the same side of the battery cell 10, as shown in the figure. Figure 1 In some embodiments, the first tab 11 and the second tab 12 are respectively located on both sides of the battery cell 10, referring to... Figure 2 .

[0022] In some embodiments, an adhesive layer 50 is provided on both the first tab 11 and the second tab 12. The first encapsulation body 20 is bonded to a portion of the adhesive layer 50, and the second encapsulation body 30 is bonded to the other portion of the adhesive layer 50. Only one application of the adhesive layer 50 is required to simultaneously encapsulate the first encapsulation body 20 and the second encapsulation body 30, simplifying the encapsulation process. Further, the length L of the adhesive layer 50 on the first tab 11 along the extension direction of the first tab 11 is 10mm-20mm; and / or, the length L of the adhesive layer 50 on the second tab 12 along the extension direction of the second tab 12 is 10mm-20mm. For example, this length L can be any value among 10mm, 12mm, 15mm, 18mm, 20mm, or 10mm-20mm. This length setting further ensures that only one application of the adhesive layer 50 is required to simultaneously encapsulate the first encapsulation body 20 and the second encapsulation body 30. Furthermore, if the adhesive layer 50 is too short, the first package 20 and the second package 30 will not adhere firmly; if the adhesive layer 50 is too long, there will be exposed portions of the adhesive layer 50 after both the first package 20 and the second package 30 are encapsulated, resulting in waste of the adhesive layer 50 and making it prone to attracting impurities. By setting the length of the adhesive layer 50 to 10mm-20mm, both a firm bond between the first package 20 and the second package 30 can be ensured, while also avoiding waste of the adhesive layer 50.

[0023] In some embodiments, the distance D between the outer end of the connection between the first package 20 and the first tab 11 and the inner end of the connection between the second package 30 and the first tab 11 is 0.5mm-8mm; and / or, the distance D between the outer end of the connection between the first package 20 and the first tab 11 and the inner end of the connection between the second package 30 and the first tab 11 is 0.5mm-8mm. For example, D can be any value among 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm or 0.5mm-8mm. This arrangement ensures that the first package 20 and the second package 30 have a suitable distance on the tab side of the cell 10, thereby ensuring that the fluid medium can fill the tab side of the cell 10, and thus ensuring that the pressure can be uniformly transmitted to the tab side of the cell 10. It should be noted that the connection between the first package 20 and the first tab 11 and the second tab 12 can be understood as a heat-sealing point or heat-sealing area, and similarly, the connection between the second package 30 and the first tab 11 and the second tab 12 can also be understood as a heat-sealing point or heat-sealing area.

[0024] In some embodiments, the cross-sectional area of ​​the second package 30 is larger than the cross-sectional area of ​​the first package 20, and the cross-sectional area of ​​the first package 20 is 80%-98% of the cross-sectional area of ​​the second package 30. For example, the cross-sectional area of ​​the first package 20 is any one of 80%, 82%, 85%, 88%, 90%, 92%, 95%, 98%, or 80%-98% of the cross-sectional area of ​​the second package 30. Preferably, the cross-sectional area of ​​the first package 20 is 85%-90% of the cross-sectional area of ​​the second package 30. For example, the cross-sectional area of ​​the first package 20 is any one of 85%, 86%, 87%, 88%, 89%, 90%, or 85%-90% of the cross-sectional area of ​​the second package 30. If the cross-sectional area of ​​the second package 30 differs too little from that of the first package 20, the volume of the cavity 40 between them will be too small, resulting in insufficient fluid medium filling and inability to guarantee pressure transmission. Conversely, if the cross-sectional area of ​​the second package 30 differs too much from that of the first package 20, the volume of the cavity 40 will be too large, leading to excessive fluid medium filling, waste of fluid medium, and an excessively large overall structure. The above design ensures that the volume of the cavity 40 between the second package 30 and the first package 20 is appropriate, achieving both uniform pressure transmission and preventing fluid medium waste, while also ensuring that the overall structure remains relatively compact.

[0025] In some embodiments, the second package 30 includes three packaging edges. The second package 30 is a one-piece structure. During packaging, the one-piece second package 30 is first folded in half, leaving three sides to be packaged. Two sides are packaged first, then a fluid medium is injected between the second package 30 and the first package 20 through the unpackaged side. Finally, the last side of the second package 30 is packaged, thus forming three packaging edges. In some embodiments, the second package 30 includes four packaging edges. The second package 30 includes two sheet structures. During packaging, the two sheet structures are first aligned, leaving four sides to be packaged. Three sides are packaged first, then a fluid medium is injected between the second package 30 and the first package 20 through the unpackaged side. Finally, the last side of the second package 30 is packaged, thus forming four packaging edges. Optionally, the first package 20 and / or the second package 30 are aluminum-plastic films.

[0026] In some embodiments, the fluid medium must be a non-conductive liquid, such as a mixture of pure water, oil, or ethylene glycol. In some embodiments, the fluid medium fills the receiving cavity 40 to ensure that the fluid medium uniformly transmits pressure, thereby ensuring the uniformity of force on the battery cell 10. It should be noted that "filling the receiving cavity 40" means that the fluid medium completely fills the receiving cavity 40 without leaving any gaps.

[0027] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A cell packaging structure, characterized in that, include: Battery cell (10); The first package (20) is encapsulated on the outer surface of the battery cell (10); The second package (30) is packaged outside the first package (20), and a receiving cavity (40) is formed between the second package (30) and the first package (20); A fluid medium is filled in the receiving cavity (40).

2. The cell packaging structure according to claim 1, characterized in that, The battery cell (10) is provided with a first tab (11) and a second tab (12) of opposite polarity. A portion of the first tab (11) and the second tab (12) are connected to the first package (20), and another portion of the first tab (11) and the second tab (12) are located outside the first package (20) and connected to the second package (30).

3. The cell packaging structure according to claim 2, characterized in that, The first tab (11) and the second tab (12) are located on the same side of the battery cell (10).

4. The cell packaging structure according to claim 2, characterized in that, The first tab (11) and the second tab (12) are located on both sides of the battery cell (10).

5. The cell packaging structure according to any one of claims 2-4, characterized in that, Both the first tab (11) and the second tab (12) are provided with an adhesive layer (50). The first encapsulation body (20) is bonded to a part of the adhesive layer (50), and the second encapsulation body (30) is bonded to another part of the adhesive layer (50).

6. The cell packaging structure according to claim 5, characterized in that, The length L of the adhesive layer (50) on the first electrode (11) along the extension direction of the first electrode (11) is 10mm-20mm.

7. The cell packaging structure according to claim 5, characterized in that, The length L of the adhesive layer (50) on the second electrode tab (12) along the extension direction of the second electrode tab (12) is 10mm-20mm.

8. The cell packaging structure according to any one of claims 2-4, characterized in that, The distance D between the outer end of the connection between the first package (20) and the first tab (11) and the inner end of the connection between the second package (30) and the first tab (11) is 0.5mm-8mm.

9. The cell packaging structure according to any one of claims 2-4, characterized in that, The distance D between the outer end of the connection between the first package (20) and the second tab (12) and the inner end of the connection between the second package (30) and the second tab (12) is 0.5mm-8mm.

10. The cell packaging structure according to any one of claims 1-4, characterized in that, The cross-sectional area of ​​the second package (30) is larger than that of the first package (20), and the cross-sectional area of ​​the first package (20) is 80%-98% of the cross-sectional area of ​​the second package (30).

11. The cell packaging structure according to claim 10, characterized in that, The cross-sectional area of ​​the first package (20) is 85%-90% of the cross-sectional area of ​​the second package (30).

12. The cell packaging structure according to any one of claims 1-4, characterized in that, The second package (30) is an integral structure, and the second package (30) includes three package edges.

13. The cell packaging structure according to any one of claims 1-4, characterized in that, The second package (30) includes two substructures, and the edges of the two substructures are connected to form four package edges.

14. The cell packaging structure according to any one of claims 1-4, characterized in that, The fluid medium fills the receiving cavity (40).

15. The cell packaging structure according to any one of claims 1-4, characterized in that, The first package (20) and / or the second package (30) are aluminum-plastic films.

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