Soft package battery, battery pack and electronic device

Abstract

The embodiment of the utility model provides a soft package battery, comprising: an electrode assembly comprising a tab led out along the length direction; the electrode assembly is wrapped by the insulating film, and the tabs extend out of the insulating film; the electrode assembly is wrapped by the insulating film, the packaging film is used for packaging the electrode assembly wrapped by the insulating film, the packaging film is provided with a sealing edge for sealing the electrode assembly, the tab extends out of the sealing edge and is fixed on the sealing edge, the insulating film is provided with an extension part extending towards the sealing edge, and the extension part is fixed on the sealing edge. The utility model aims to provide the soft package battery, the battery pack and the electronic device, so as to at least prevent the tabs from being torn.

Description

Technical Field

[0001] This utility model relates to a soft-pack battery, a battery pack, and an electronic device. Background Technology

[0002] The packaging materials and structure of pouch batteries give them a number of advantages, such as good safety performance, light weight, low internal resistance, and customizable shape. One technical problem with existing pouch batteries is the fixation of the electrode assembly within the battery; when vibration occurs, there is a risk that the electrode tabs will tear. Utility Model Content

[0003] In view of the problems existing in the related technologies, the purpose of this utility model is to provide a soft-pack battery, battery pack and electronic device, so as to at least avoid the tabs being torn.

[0004] To achieve the above objectives, embodiments of this application provide a pouch battery, comprising: an electrode assembly including tabs extending along its length; an insulating film wrapping the electrode assembly, the tabs extending from the insulating film; and a packaging film encapsulating the electrode assembly wrapped by the insulating film, the packaging film having a sealing edge that seals the electrode assembly, the tabs extending from and fixed to the sealing edge, and the insulating film having an extension portion extending toward the sealing edge, the extension portion being fixed to the sealing edge.

[0005] In some embodiments, the electrode assembly has two large surfaces facing away from each other along the thickness direction, and the insulating film has a second portion and a third portion respectively covering the two large surfaces, the second portion and the third portion being provided with a plurality of second holes, the diameter of the second holes ranging from 2 mm to 5 mm.

[0006] In some embodiments, the electrode assembly has a side surface along one side of the width direction, and the insulating film has a first portion covering the side surface, the first portion being located between the sealing edge and the electrode assembly, the first portion being provided with a plurality of first holes.

[0007] In some embodiments, the diameter of the first hole is smaller than the diameter of the second hole.

[0008] In some embodiments, the plurality of first holes on the first portion have a consistent spacing, and the plurality of second holes on the second portion and the third portion have a consistent spacing.

[0009] In some embodiments, the electrode assembly has a first end face and a second end face opposite to each other along the length direction, and the tabs include a positive tab and a negative tab extending from the first end face. Parts of the positive tab and the negative tab are sandwiched in the extension and, together with the extension, are sandwiched and fixed in the sealing edge.

[0010] In some embodiments, the electrode assembly has a first end face and a second end face opposite to each other along the length direction, and the tabs include a positive tab extending from the first end face and a negative tab extending from the second end face. Parts of the positive tab and the negative tab are sandwiched in the extension and, together with the extension, are sandwiched and fixed in the sealing edge.

[0011] In some embodiments, the packaging film includes two plastic insulating layers and a metal sealing layer sandwiched between the two plastic insulating layers, the sealing edge includes the two packaging films, and the extension is fused and fixed to the plastic insulating layers facing each other of the two packaging films.

[0012] Embodiments of this application also provide a battery pack including the aforementioned pouch battery.

[0013] Embodiments of this application also provide a battery pack, including the battery pack described above.

[0014] The beneficial technical effects of this utility model are as follows:

[0015] The insulating film covering the electrode assembly in the embodiments of this application has an extension that extends toward and is fixed to the sealing edge, so that the electrode assembly can be fixed and the tabs can be prevented from being torn due to vibration. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A perspective view of an electrode assembly wrapped with an insulating film is shown.

[0018] Figure 2 A front view of the electrode assembly wrapped with an insulating film is shown.

[0019] Figure 3 The unfolded insulating film is shown.

[0020] Figure 4 A packaging film according to an embodiment of this application is shown.

[0021] Figure 5 A cross-sectional view of the packaging film is shown.

[0022] Figure 6 The image shows an electrode assembly wrapped in an insulating film being placed into a crater.

[0023] Figure 7 It shows that Figure 6 The lower half of the middle packaging film is folded to cover the electrode assembly.

[0024] Figure 8 Will Figure 7 The topmost layer of packaging film is hidden to reveal its internal structure.

[0025] Figure 9 A pouch cell battery according to an embodiment of this application is shown.

[0026] Figure 10 Will Figure 9 The topmost layer of packaging film is hidden to reveal its internal structure.

[0027] Figure 11 It shows the relationship with Figure 1 Different implementations.

[0028] Figure 12 A schematic diagram is shown when the electronic device according to an embodiment of this application is a vehicle. Detailed Implementation

[0029] To better understand the spirit of the embodiments of this application, the following description is based on some preferred embodiments of this application.

[0030] Embodiments of this application will be described in detail below. Throughout this specification, identical or similar components and components having identical or similar functions are indicated by similar reference numerals. The embodiments described herein with reference to the accompanying drawings are illustrative and diagrammatic in nature and are intended to provide a basic understanding of this application. The embodiments of this application should not be construed as limiting this application.

[0031] As used herein, the terms “approximately,” “generally,” “substantially,” and “about” are used to describe and indicate minor variations. When used in conjunction with an event or situation, these terms may refer to examples in which the event or situation occurred precisely or in examples in which the event or situation occurred very approximately.

[0032] In this specification, unless otherwise specified or limited, relative terms such as “central,” “longitudinal,” “lateral,” “front,” “rear,” “right,” “left,” “inner,” “outer,” “lower,” “higher,” “horizontal,” “vertical,” “above,” “below,” “above,” “below,” “top,” “bottom,” and their derivatives (e.g., “horizontally,” “downward,” “upward,” etc.) should be interpreted as referring to the directions described in the discussion or depicted in the accompanying drawings. These relative terms are used for descriptive convenience only and do not require that this application be constructed or operated in a particular orientation.

[0033] For ease of description, "first," "second," "third," etc., can be used in this article to distinguish different components of a figure or a series of figures. "First," "second," "third," etc., are not intended to describe the corresponding components.

[0034] The packaging materials and structure of pouch batteries give them a series of advantages, such as good safety performance. Due to the use of packaging film, in the event of a safety issue, pouch batteries generally bulge and crack, unlike steel-cased or aluminum-cased batteries which may explode. Secondly, they are lightweight and have high energy density; pouch batteries are 40% lighter than steel-cased lithium batteries of the same capacity and 20% lighter than aluminum-cased lithium batteries. They also have low internal resistance; the internal resistance of pouch batteries is lower than that of other lithium battery structures, allowing for higher charge and discharge rates. Furthermore, the shape of pouch batteries can be customized to meet specific needs, offering greater design flexibility and an advantage in developing new battery models.

[0035] Of course, pouch batteries also have disadvantages. The packaging film relies on imports, the manufacturing process is complex, and the automation level of the production line is not as high as that of square aluminum-cased batteries, resulting in lower production efficiency. In recent years, with the continuous increase in demand for lithium-ion batteries, the requirements for improving production line processes have been constantly increasing, and the life cycle requirements for pouch batteries have also become increasingly stringent. One technical problem with existing pouch batteries is the fixation of the electrode components within the battery; when vibration occurs, there is a risk that the electrode tabs will be torn.

[0036] The difference between pouch batteries and other prismatic and cylindrical batteries lies in the use of a packaging film. The reliability of this film determines the battery's lifespan, and the quality of the thermoforming sealing directly impacts the battery's safety and performance. A weak point in thermoforming is the sealing after degassing. The degassing process after electrolyte injection (generally called the second sealing) is significantly more difficult to pass than the top and side sealing processes before electrolyte injection (generally called the first sealing). Ensuring successful sealing even with electrolyte present remains a challenge for the industry.

[0037] The existing packaging technology has the following main problems: Currently, vacuum packaging mostly uses top and bottom flat end caps with a width of 4mm to 5mm. The free electrolyte in the packaging area is extracted by vacuuming. When there is a lot of free electrolyte, there is a problem of electrolyte accumulation in the packaging area. The accumulated electrolyte will absorb the heat of the end cap, affecting the uniform fusion of the two packaging films, ultimately leading to poor melt bonding or insufficient packaging strength after packaging, causing leakage safety accidents.

[0038] Figures 1 to 10 The installation process of a pouch battery 100 according to an embodiment of this application is shown.

[0039] Figure 1 A perspective view of the electrode assembly 10 wrapped with an insulating film 30 is shown. Figure 2 A front view of the electrode assembly 10 wrapped with an insulating film 30 is shown, in which the outline of the electrode assembly 10 covered by the insulating film 30 is shown in dashed lines. Figure 3 The unfolded insulating film 30 is shown. The electrode assembly 10 includes tabs (including a positive tab 20 and a negative tab 22) extending along the length direction L from the insulating film 30. The electrode assembly 10 has two large surfaces facing away from each other along the thickness direction, and the insulating film 30 has a second portion 32 and a third portion 33 covering the two large surfaces respectively, and the second portion 32 and the third portion 33 are provided with a plurality of second holes 52.

[0040] Figure 4 A packaging film 40 according to an embodiment of the present application is shown. The packaging film 40 has two perforations 401, 402 for accommodating the electrode assembly 10. Figure 5 A cross-sectional view of the packaging film 40 is shown. The packaging film 40 includes two plastic insulating layers 46 and a metal sealing layer 48 sandwiched between the two plastic insulating layers 46 (for example, the packaging film 40 is an aluminum-plastic film, the metal sealing layer 48 is an aluminum layer, and the material of the plastic insulating layer 46 is, for example, polypropylene). Figure 6 The image shows an electrode assembly 10, wrapped in an insulating film 30, being placed into a pit 401.

[0041] Figure 7 It shows that Figure 6 The lower half of the intermediate packaging film 40 is folded to cover the electrode assembly 10, and then formed Figure 7 The sealing edge 42 (commonly referred to as a seal) is located on the left and top sides, where adjacent plastic insulating layers 46 of two layers of packaging film 40 are fused together to form the sealing edge 42. Electrolyte is injected into the opening on the right side, and then the seal is formed. Figure 7 The sealing edge 42 on the right side of the middle is subjected to a chemical formation process. Figure 8 Will Figure 7The uppermost packaging film 40 is hidden (or transparent) to reveal its internal structure. The portion of the packaging film 40 located on the right side of the electrode assembly 10 is called an air bag / bladder, used to contain the gases generated during formation. On the left and upper sides of the electrode assembly 10, the extension 36 of the insulating film 30 is sandwiched within the packaging film 40, and during heat sealing, the plastic insulating layer 46 facing each other with the packaging film 40 is fused together and fixed to the sealing edge 42. The electrode tabs extend from the sealing edge 42 and are fixed to the sealing edge 42. The insulating film 30 is a Mylar film, and the material is, for example, polypropylene (PP). The sealing edge 42 comprises two layers of packaging film 40, and the extension 36 is fused and fixed to the plastic insulating layer 46 facing each other with the two layers of packaging film 40. This can be achieved together in the heat sealing process, without the need for additional steps to fix the electrode assembly 10.

[0042] Figure 9 The diagram illustrates the process after the formation step, where the gas bag is removed, a vacuum is drawn to extract the gases generated during formation, and excess electrolyte is removed, thus forming... Figure 9 The sealing edge 42 on the right side (commonly referred to as the second seal). Since the electrode assembly 10 is wrapped by the insulating film 30, it prevents a portion of the electrolyte from being drawn out into the second seal area. The insulating film 30 has a second hole 32 for the gas generated during formation to pass through. The diameter of the second hole 52 ranges from 2 mm to 5 mm. This ensures that the gas can be extracted while preventing the electrolyte from being drawn into the second seal area, which would result in a poor seal. Figure 10 Will Figure 9 The uppermost packaging film 40 is hidden (or transparent) to show its internal structure. The extension 36 of the packaging film 10 located on the right side of the electrode assembly 10 is sandwiched in the packaging film 40, and during heat sealing, the plastic insulating layer 46 facing each other with the packaging film 40 is fused together and fixed to the sealing edge 42.

[0043] Embodiments of this application provide a pouch battery 100, in which a packaging film 40 encapsulates an electrode assembly 10 wrapped by an insulating film 30. The packaging film 40 has a sealing edge 42 that seals the electrode assembly 10. On at least one side of the electrode assembly 10, the insulating film 30 has an extension 36 extending toward the sealing edge 42 and fixed to the sealing edge 42. The insulating film 30 wrapping the electrode assembly 10 in this embodiment has an extension 36 extending toward and fixed to the sealing edge 42, so that the electrode assembly 10 can be fixed, preventing the tabs from tearing due to vibration. The tabs of the pouch battery 100 typically include an inner tab (located inside the packaging film 40, for example, the inner tab material of the positive electrode tab 20 is aluminum, and the inner tab material of the negative electrode 22 is aluminum) that is part of the current collector of the electrode sheet of the electrode assembly 10, and an outer tab (typically called a tab, located outside the packaging film 40) welded to the inner tab. By fixing the electrode assembly 10, damage to the weld between the inner and outer tabs can be avoided.

[0044] Figure 11 It shows the relationship with Figure 1 In different embodiments, the electrode assembly 10 has a side surface 11 along one side of its width, and the insulating film 30 has a first portion 31 covering the side surface 11. The first portion 31 is located between the sealing edge 42 and the electrode assembly 10, and the first portion 31 is provided with a plurality of first holes 51. In this embodiment, before the electrode assembly 10 wrapped by the insulating film 30 is placed in the packaging film 40, not only are the extensions 36 of the insulating film 30 at one end of the electrode tab of the electrode assembly 10 fixed together to cover the first end face of the electrode assembly 10 leading out of the tab, but the first portion 31 of the insulating film 30 also covers the first side surface 11 of the electrode assembly 10. In the subsequent electrolyte injection process, the first holes 51 on the first portion 31 are used for the electrolyte to enter the electrode assembly 10. In the vacuum sealing process, the first holes 51 on the first portion 31 are used for the gas generated by formation, and compared to Figure 1 In the illustrated embodiment, the first portion 31 covers the side 11 of the electrode assembly 10 before the vacuuming process, which better prevents the electrolyte from being drawn to the seal of the packaging film 40, thus avoiding poor bonding of the plastic insulation layer 46 of the sealing edge 42. Since the thickness (along the thickness direction T) of the electrode assembly 10 is less than its width (along the width direction W), there is only one row of first holes 51, and their diameter is smaller than the diameter of the second holes 52. The plurality of first holes 51 on the first portion 31 have a consistent spacing, and the plurality of second holes 52 on the second portion 32 and the third portion 33 have a consistent spacing. The relatively uniform distribution of the first holes 51 and second holes 52 on the surface of the electrode assembly 10 allows for more effective extraction of the gases generated during the vacuuming process.

[0045] Figures 1 to 11 In the illustrated embodiment, the electrode assembly 10 has a first end face and a second end face opposite to each other along its length. The tabs include a positive tab 20 and a negative tab 22 extending from the first end face. Parts of the positive tab 20 and the negative tab 22 are sandwiched in the extension 36 and, together with the extension 36, are sandwiched and fixed in the sealing edge 42. The positive tab 20 and the negative tab 22 extend from the same end of the electrode assembly 10. On the side where the tabs are located, the extension 36 of the insulating film 30 and the tabs are fixed together in the sealing edge 42 to further prevent the tabs from being torn.

[0046] In other embodiments, the positive electrode tab 20 extends from the first end face, and the negative electrode tab 22 extends from the second end face. A portion of both the positive and negative electrode tabs 20 and 22 are also sandwiched within the extension 36, and together with the extension 36, are sandwiched and fixed within the sealing edge 42. The positive and negative electrode tabs 20 and 22 are located at opposite ends of the electrode assembly 10, further avoiding the possibility of a short circuit due to contact between the positive and negative electrode tabs 12 and 32 compared to embodiments where they are located at the same end. Furthermore, both the positive and negative electrode tabs 20 and 22 are fixed to the sealing edge 42 together with the extension 36 of the insulating film 30, further preventing the positive and negative electrode tabs 20 and 22 from being torn.

[0047] The embodiments of this application provide an insulating film 30 for improving the double sealing of a soft-pack battery 100. It does not require modification of the sealing head or vacuum equipment. It can effectively prevent the electrolyte from being extracted and accumulating in the encapsulation area when there is a lot of free electrolyte, which would lead to poor melt bonding or insufficient encapsulation strength after encapsulation, and greatly improve the safety of leakage accidents.

[0048] This utility model also provides an electronic device 1000. For ease of explanation, the following embodiments will use a vehicle as an example to illustrate the electronic device 1000. Figure 12 This illustration shows an electronic device 1000 as a vehicle according to an embodiment of this application. A battery pack 1002 is installed inside the vehicle. The battery pack 1002 includes a pouch battery 100 according to an embodiment of this application. The battery pack 1002 can be located at the bottom, front, or rear of the vehicle body 1001. The battery pack 1002 can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The working part of the electronic device 1000 is electrically connected to the battery pack 1002 to obtain electrical power. The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, but are not limited thereto. The battery pack 1002 provides electrical power for the vehicle's operation or the operation of its internal electrical components. However, in other embodiments, the electronic device 1000 can also be a mobile phone, portable device, laptop computer, ship, spacecraft, electric toy, power tool, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc.; the working unit is a unit component that can obtain electrical energy from the battery pack 1002 and perform corresponding tasks, such as the fan blade rotation unit of a fan, the vacuuming working unit of a vacuum cleaner, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, and electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application embodiment does not impose any special limitations on the above-mentioned electronic device 1000.

[0049] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A pouch battery, characterized by, The soft package battery comprises: an electrode assembly comprising a tab led out in a length direction; an insulating film wrapping the electrode assembly, the tab being led out from the insulating film; a packaging film encapsulating the electrode assembly wrapped by the insulating film, the packaging film having a sealing edge sealing the electrode assembly, the tab being led out from and fixed to the sealing edge, the insulating film having an extension extending towards the sealing edge, the extension being fixed to the sealing edge.

2. The soft package battery according to claim 1, wherein the electrode assembly has two major surfaces opposite in a thickness direction, the insulating film has a second portion and a third portion covering the two major surfaces respectively, the second portion and the third portion are provided with a plurality of second holes, and a diameter of the second holes ranges from 2 mm to 5 mm.

3. The soft package battery according to claim 2, wherein the electrode assembly has a side surface on one side in a width direction, the insulating film has a first portion covering the side surface, the first portion is located between the sealing edge and the electrode assembly, and the first portion is provided with a plurality of first holes.

4. The pouch battery of claim 3, wherein, a diameter of the first holes is smaller than a diameter of the second holes.

5. The soft package battery according to claim 3, wherein the plurality of first holes on the first portion have a uniform pitch, and the plurality of second holes on the second portion and the third portion have a uniform pitch.

6. The soft package battery according to claim 1, wherein the electrode assembly has a first end surface and a second end surface opposite in the length direction, the tab comprises a positive tab led out from the first end surface and a negative tab led out from the second end surface, parts of the positive tab and the negative tab are clamped in the extension, and the positive tab, the negative tab and the extension are clamped and fixed in the sealing edge together.

7. The soft package battery according to claim 1, wherein the electrode assembly has a first end surface and a second end surface opposite in the length direction, the tab comprises a positive tab led out from the first end surface and a negative tab led out from the second end surface, parts of the positive tab and the negative tab are clamped in the extension, and the positive tab, the negative tab and the extension are clamped and fixed in the sealing edge together. 8.The pouch battery of claim 1, wherein, the packaging film comprises two plastic insulating layers and a metal sealing layer clamped between the two plastic insulating layers, the sealing edge comprises two layers of the packaging film, and the extension is fixed to the plastic insulating layers of the two layers of the packaging film facing each other by melting.

9. A battery pack characterized by comprising: The soft package battery according to any one of claims 1 to 8.

10. An electronic device, comprising: The battery pack according to claim 9.

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