Battery case and battery

Abstract

The utility model provides a kind of battery case and battery belongs to energy storage equipment technical field, comprising: at least one piece by flexible material is made of surrounding surface, surrounding surface is enclosed and has the accommodating cavity of through opening in two ends;End cover, the number of end cover is two, and pole is provided on end cover, two end covers are respectively sealed and fixed at the through opening of accommodating cavity, and closed accommodating space is formed between end cover and accommodating cavity, and accommodating space is used to accommodate roll core, one of end cover is provided with liquid injection hole and is communicated with accommodating space, and overpressure release part is also provided on the end cover with liquid injection hole and is sealed with end cover Connection to realize the closure of liquid injection hole. Advantage is that surrounding surface is made of flexible material, and surrounding surface only needs to be sealed and connected after folding along opposite two sides, i. e. accommodating cavity with two ends through can be formed, without being limited by the extension rate of flexible material, so that the thickness of battery cell can be flexibly designed according to demand, which is beneficial to the development and application of high-energy-density battery cell.

Description

Technical Field

[0001] This utility model belongs to the field of energy storage equipment technology, and in particular relates to a battery casing and a battery. Background Technology

[0002] With the rapid development of the new energy industry, especially the increasing demand for high-energy-density, high-safety, and lightweight batteries from electric vehicles, energy storage systems, and portable electronic devices, pouch lithium-ion batteries have gradually become one of the mainstream products in the market due to their advantages such as flexible structure, high energy density, and low internal resistance. In the packaging structure of pouch batteries, the design of the battery casing directly affects its electrical performance, safety performance, and manufacturing efficiency.

[0003] Currently, traditional pouch cells typically use an aluminum-plastic film to create cavities for housing the battery core through a perforation process, followed by four-sided heat sealing. However, perforation relies on the elongation of the aluminum-plastic film material, limiting the flexibility of cell thickness and shape design. Furthermore, a secondary heat sealing operation is required after electrolyte injection, increasing process steps and reducing production efficiency. Simultaneously, traditional structures also have certain safety drawbacks. For example, in the event of thermal runaway, the lack of a directional pressure relief mechanism can lead to disordered gas ejection, triggering a chain reaction and threatening the safety of the entire battery system. Summary of the Invention

[0004] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a structure that utilizes folding to form the battery casing, replacing the existing composite membrane punching production method.

[0005] The objective of this utility model can be achieved through the following technical solution: a battery casing, comprising:

[0006] At least one surrounding surface made of flexible material, the surrounding surface forming a receiving cavity with through openings at both ends;

[0007] The end caps are provided in two form. Each end cap is provided with a pole post. The two end caps are respectively sealed and fixed at the through opening of the receiving cavity. The end caps and the receiving cavity form a closed receiving space for accommodating the winding core. One of the end caps is provided with a liquid injection hole that communicates with the receiving space. The end cap with the liquid injection hole is also provided with an overpressure relief part that is sealed to the end cap to achieve the closure of the liquid injection hole.

[0008] In one of the battery casings described above, the overpressure relief section includes an explosion-proof membrane, which is sealed to the end cap.

[0009] In one of the battery casings described above, a connecting portion is integrally provided on the end cap, the connecting portion extends into the receiving cavity and is sealed to the inner wall of the receiving cavity, and the end cap is sealed to the end face of the surrounding surface.

[0010] In one of the battery casings described above, the surrounding surface is provided with multiple parallel surrounding fold lines. After the surrounding surface is folded along the surrounding fold lines, multiple surrounding edges are formed to enclose a receiving cavity with through openings at both ends.

[0011] In one of the battery casings described above, sealing surfaces are integrally formed on opposite sides of the surrounding surface along a direction parallel to the surrounding fold line, and the corresponding sealing surfaces are sealed together to achieve the enclosure of the surrounding surface.

[0012] In one of the battery casings described above, a first fold line is provided on the sealing surface to form a folded edge after folding.

[0013] In one of the battery casings described above, a second folding line is provided on the folded edge, and the folded edge is folded along the second folding line to form a folded portion.

[0014] In one of the battery casings described above, the material of the surrounding surface is an aluminum-plastic film.

[0015] In one of the battery casings described above, the end cap is made of plastic.

[0016] A battery comprising the aforementioned battery casing.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] (1) The surrounding surface is made of flexible material. The surrounding surface only needs to be folded and sealed along the opposite sides to form a cavity that runs through both ends. It is not limited by the elongation rate of the flexible material, so the cell thickness can be flexibly designed according to the needs, which is conducive to the development and application of high energy density cells.

[0019] (2) By setting an injection hole on the end cap, electrolyte can be injected directly through it, avoiding the traditional process of injecting electrolyte first and then performing secondary side sealing, reducing production steps and speeding up the entire production process; in addition, the overpressure relief part set on the end cap can provide a controllable pressure relief path in the event of thermal runaway, thereby enhancing the safety performance of the battery. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the battery casing structure;

[0021] Figure 2 yes Figure 1 A schematic diagram of the structure after removing the overpressure relief section;

[0022] Figure 3 yes Figure 2 A magnified view of a portion of point A in the middle;

[0023] Figure 4 yes Figure 1 A schematic diagram of the cross-sectional structure;

[0024] Figure 5 This is a schematic diagram of the structure when the surrounding surface is not folded.

[0025] In the figure, 100 is the surrounding surface; 101 is the receiving cavity; 102 is the surrounding fold line; 103 is the sealing surface; 104 is the first fold line; 105 is the second fold line; 106 is the fold; 107 is the folded part; 200 is the end cap; 201 is the pole; 202 is the injection hole; 203 is the connecting part; and 204 is the overpressure release part. Detailed Implementation

[0026] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0027] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0028] like Figures 1-5 As shown, a battery casing includes:

[0029] At least one surrounding surface 100 made of flexible material, the surrounding surface 100 forming a receiving cavity 101 with through openings at both ends;

[0030] There are two end caps 200. Each end cap 200 is provided with a pole post 201. The two end caps 200 are respectively sealed and fixed at the through opening of the receiving cavity 101. The end caps 200 and the receiving cavity 101 form a closed receiving space for accommodating the winding core. One of the end caps 200 is provided with an injection hole 202 that communicates with the receiving space. An overpressure release part 204 is provided on the end cap 200 and is sealed to the end cap 200 to seal the injection hole 202.

[0031] In this embodiment, the surrounding surface 100 is made of flexible material. The surrounding surface 100 only needs to be folded and sealed along the opposite sides to form a cavity 101 that runs through both ends. It is not limited by the elongation rate of the flexible material, so the cell thickness can be flexibly designed according to the requirements, which is conducive to the development and application of high energy density cells.

[0032] By providing an injection hole 202 on the end cap 200, electrolyte can be injected directly through it, avoiding the traditional process of injecting electrolyte first and then performing secondary side sealing, reducing production steps and speeding up the entire production process; in addition, the overpressure relief part 204 provided on the end cap 200 can provide a controllable pressure relief path in the event of thermal runaway, thereby enhancing the safety performance of the battery.

[0033] like Figure 1 As shown, specifically, the overpressure relief unit 204 includes an explosion-proof membrane, which is sealed to the end cap 200. It automatically opens when the internal pressure of the battery exceeds a set threshold, releasing excessive internal pressure in a timely manner and avoiding the risk of explosion or rupture due to excessive internal pressure. Compared to other forms of overpressure relief devices (such as spring-loaded valves), the explosion-proof membrane occupies less space, helping to reduce the overall size and weight of the battery pack.

[0034] More preferably, the end cap 200 is integrally provided with a connecting part 203, which extends into the receiving cavity 101 and is sealed to the inner wall of the receiving cavity 101, and the end cap 200 is sealed to the end face of the surrounding surface 100.

[0035] In this embodiment, a double sealing protection is formed by the sealing connection between the connecting part 203 and the inner wall of the receiving cavity 101, and the sealing connection between the end cap 200 and the end face of the surrounding surface 100. This enhances the sealing performance of the entire battery casing and improves the overall stability and durability of the structure. Moreover, the design of the connecting part 203 extending deep into the receiving cavity 101 increases the number of sealing points and the sealing area, effectively reducing the risk of electrolyte leakage.

[0036] Further defined, the surrounding surface 100 is provided with multiple parallel surrounding fold lines 102. After the surrounding surface 100 is folded along the surrounding fold lines 102, multiple surrounding edges are formed to form a receiving cavity 101 with through openings at both ends.

[0037] Compared to traditional punching and forming methods, folding and forming using pre-set folding lines eliminates the need for complex molds, reduces the requirements for the elongation rate of flexible materials, simplifies the manufacturing process, and improves production efficiency and product consistency. By adjusting the number and spacing of the folding lines, the thickness and external dimensions of the receiving cavity 101 can be flexibly controlled to meet the packaging requirements of cells with different capacities and shapes, enhancing the adaptability and application range of the battery casing structure.

[0038] Further defining, along a direction parallel to the surrounding fold line 102, sealing surfaces 103 are integrally provided on opposite sides of the surrounding surface 100, and the corresponding sealing surfaces 103 are sealed together to achieve the enclosure of the surrounding surface 100.

[0039] In this invention, the one-piece molded sealing surface 103 design reduces reliance on complex molds and multiple heat-sealing steps, simplifying the manufacturing process. This improves production efficiency, reduces errors and material waste caused by multiple operations, and enhances product consistency and yield. The one-piece molded sealing surface 103 design allows for more flexible adjustment of the size and shape of the surrounding surface 100, thereby optimizing the internal spatial layout of the battery casing.

[0040] like Figure 4 As shown, as an alternative, the battery casing is square in shape. Because of its simple shape, it can be folded into shape using a single surrounding surface 100. As another alternative, the shape of the receiving cavity 101 can also be L-shaped, hexagonal, or other shapes. These shapes are relatively complex. In the production process, multiple surrounding surfaces 100 can be folded into partial shapes and then sealed and connected by the sealing surface 103 to form a through receiving cavity 101.

[0041] Preferably, the sealing surface 103 is provided with a first fold line 104, which forms a folded edge 106 after folding.

[0042] More preferably, the folded edge 106 is provided with a second fold line 105, and the folded edge 106 is folded along the second fold line 105 to form a folded part 107.

[0043] In this embodiment, as Figure 3 As shown, as an optional solution, the sealing surface 103 after sealing connection is folded along the first fold line 104, folding the originally extended sealing surface 103 close to the surrounding edge along its root, effectively reducing the external size of the battery case and avoiding space waste caused by the outward expansion of the sealing surface 103. Furthermore, by setting a second fold line 105 on the folded edge 106 and folding inward twice to form a folded portion 107, the connecting portion 203 forms a multi-layered structure, significantly increasing the effective contact area of ​​heat sealing or other sealing methods. The three-dimensional structure formed by the folded portion 107 enhances the mechanical strength of the connecting portion 203, maintaining a good sealing state even under external pressure or temperature changes, preventing electrolyte leakage or moisture intrusion.

[0044] It should be noted that in the actual production process, the sealing surface 103 is first folded to form the folded part 107, and then the sealing surface 103 with the folded part 107 is folded towards the surrounding edge to form this side 106.

[0045] Specifically, the material of the surrounding surface 100 is an aluminum-plastic film. The aluminum-plastic film has excellent flexibility, allowing it to be easily folded along the pre-set fold lines 106 to form the required folds and folded portions 107, adapting to the packaging needs of battery cells of different shapes and sizes. The aluminum-plastic film also possesses excellent gas and moisture barrier properties, ensuring the stability of the battery's internal environment, preventing chemical reactions caused by contact between the electrolyte and external air, and extending battery life.

[0046] It should be noted that, in addition to aluminum-plastic film, the flexible materials mentioned above can also be selected from a variety of materials such as multilayer co-extruded film, thermoplastic elastomer, and metal-organic framework materials.

[0047] Furthermore, the end cap 200 is made of plastic. Plastic materials have good plasticity, allowing for the efficient manufacture of complex shapes and structures through processes such as injection molding and die casting, simplifying the manufacturing process of the end cap 200. When the plastic material is connected to the aluminum-plastic film via heat sealing or other sealing methods, it provides a good sealing interface, enhancing the overall sealing performance of the battery casing and preventing electrolyte leakage or external moisture intrusion. Plastic is an excellent insulating material; using plastic as the end cap 200 effectively prevents the battery cell from contacting external conductive materials, reducing the risk of short circuits and improving battery safety.

[0048] A battery comprising the aforementioned battery casing.

[0049] It should be noted that in this utility model, the use of terms such as "first," "second," and "a" is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly defined. The terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two elements or the interaction between two elements, unless otherwise explicitly defined. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0050] Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0051] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A battery casing, characterized in that, include: At least one surrounding surface made of flexible material, the surrounding surface forming a receiving cavity with through openings at both ends; The end caps are provided in two form. Each end cap is provided with a pole post. The two end caps are respectively sealed and fixed at the through opening of the receiving cavity. The end caps and the receiving cavity form a closed receiving space for accommodating the winding core. One of the end caps is provided with a liquid injection hole that communicates with the receiving space. The end cap with the liquid injection hole is also provided with an overpressure relief part that is sealed to the end cap to achieve the closure of the liquid injection hole.

2. The battery casing according to claim 1, characterized in that, The overpressure relief section includes an explosion-proof membrane, which is sealed to the end cap.

3. A battery casing according to claim 1, characterized in that, The end cap is integrally provided with a connecting part, which extends into the receiving cavity and is sealed to the inner wall of the receiving cavity. The end cap is sealed to the end face of the surrounding surface.

4. A battery casing according to claim 1, characterized in that, The surrounding surface is provided with multiple parallel surrounding fold lines. After the surrounding surface is folded along the surrounding fold lines, multiple surrounding edges are formed to form a receiving cavity with through openings at both ends.

5. A battery casing according to claim 4, characterized in that, Along a direction parallel to the surrounding fold line, sealing surfaces are integrally provided on opposite sides of the surrounding surface, and the corresponding sealing surfaces are sealed together to achieve the enclosure of the surrounding surface.

6. A battery casing according to claim 5, characterized in that, The sealing surface is provided with a first fold line, which forms a folded edge after folding.

7. A battery casing according to claim 6, characterized in that, The folded edge is provided with a second fold line, and the folded edge is folded along the second fold line to form a folded part.

8. A battery casing according to claim 1, characterized in that, The material of the surrounding surface is aluminum-plastic film.

9. A battery casing according to claim 1, characterized in that, The end cap is made of plastic.

10. A battery, characterized in that, Includes the battery casing as described in any one of claims 1-9 above.

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