Mylar film for lithium battery, lithium battery, and electronic product

Abstract

The present application provides a Mylar film for a lithium battery, a lithium battery, and an electronic product. A bottom coating piece of the Mylar film for the lithium battery is provided with a plurality of supporting units, and the plurality of supporting units are arranged between the bottom coating piece and a housing for accommodating the Mylar film. According to the Mylar film for the lithium battery and the lithium battery in the present application, the supporting units are arranged on the bottom coating piece of the Mylar film, so that the contact between the Mylar film and the corner of the housing is avoided, avoiding the short circuit of the battery caused by breakage of the Mylar film. In addition, compared with the technical solution of providing a bottom supporting plate between the bottom coating piece and the housing to avoid contact between the Mylar film and the corner, the bottom coating piece in the present application itself is provided with the supporting units, so that the bottom supporting plate can be omitted, reducing the production cost; in addition, the step of mounting the bottom supporting plate when the battery is assembled is omitted, improving the production efficiency.

Description

Mylar film for lithium batteries, lithium batteries and electronic products Technical Field

[0001] The present application mainly relates to the technical field of lithium batteries, and specifically to a Mylar film for lithium batteries and a lithium battery. Background Art

[0002] As the power source of new energy vehicles, lithium battery technology has developed rapidly in recent years. Currently, square batteries are the most common lithium-ion battery structure. In the manufacturing process of square lithium batteries, the bare cells need to be placed in a hard square aluminum shell to complete the assembly after they are manufactured. Because the aluminum shell is relatively hard, there is a risk of scratching the bare cells. Therefore, before the bare cells are placed in the aluminum shell, they need to be covered with a soft and flexible Mylar film (Mylar or Mylar) to prevent the aluminum shell from damaging the bare cells. Existing lithium batteries often have the problem of Mylar film breaking due to contact with the corners of the aluminum shell.

[0003] Therefore, how to prevent the Mylar film from contacting the corners of the aluminum shell and breaking is an urgent problem to be solved.

[0004] Summary of the Invention

[0005] The technical problem to be solved by the present application is to provide a Mylar film for a lithium battery and a lithium battery, wherein the Mylar film for a lithium battery and the lithium battery can prevent the Mylar film from contacting the corners of an aluminum shell and being broken.

[0006] The technical solution adopted by the present application to solve the above technical problems is a Mylar film for lithium batteries, wherein the bottom covering sheet of the Mylar film has a plurality of supporting units, and the plurality of supporting units are arranged between the bottom covering sheet and a shell accommodating the Mylar film.

[0007] In an embodiment of the present application, the plurality of support units are arranged at intervals along the first direction.

[0008] In one embodiment of the present application, each of the supporting units has a chamfered side perpendicular to the bottom covering sheet.

[0009] In an embodiment of the present application, the plurality of support units are arranged at intervals along a second direction, wherein the first direction intersects with the second direction.

[0010] In one embodiment of the present application, the plurality of support units are formed by the bottom covering sheet through a stamping process.

[0011] In one embodiment of the present application, the height of each of the support units is equal to or greater than 0.5 mm.

[0012] In one embodiment of the present application, the height of each of the support units is the same.

[0013] In one embodiment of the present application, the distance between the supporting unit and the edge of the bottom covering sheet is greater than a preset distance.

[0014] On the other hand, the present application also proposes a lithium battery, comprising: a battery cell; the Mylar film for lithium batteries as described above, wherein the Mylar film for lithium batteries covers the battery cell; and a shell, the battery cell covered with the Mylar film is located in the shell, wherein the support unit in the Mylar film for lithium batteries is arranged between the bottom covering sheet and the shell.

[0015] On the other hand, the present application also proposes an electronic product, including: the lithium battery as described above.

[0016] The Mylar film for lithium batteries and lithium batteries disclosed herein utilize a support unit provided on the bottom cover sheet of the Mylar film to prevent contact between the Mylar film and the corners of the housing, thereby preventing Mylar film rupture and battery short circuits. Furthermore, compared to conventional solutions that employ a bottom support plate between the bottom cover sheet and the housing to prevent contact between the Mylar film and the corners, the bottom cover sheet of the present disclosure incorporates its own support unit, eliminating the need for a bottom support plate. This reduces production costs and eliminates the need to install the bottom support plate during battery assembly, improving production efficiency.

[0017] Summary of the Figures

[0018] The features and properties of the present invention are further described by the following examples and accompanying drawings.

[0019] FIG1 is a perspective schematic diagram of a Mylar film for a lithium battery according to an embodiment of the present application;

[0020] FIG2 is a side view schematic diagram of a Mylar film for a lithium battery according to an embodiment of the present application;

[0021] FIG3 is a rear view schematic diagram of a Mylar film for a lithium battery according to an embodiment of the present application;

[0022] FIG4 is a schematic top view of a Mylar film for a lithium battery according to another embodiment of the present application;

[0023] FIG5 is a rear view schematic diagram of a Mylar film for a lithium battery according to another embodiment of the present application.

[0024] Reference Signs Mylar film 110 Top surface 114b Corner 111 First edge 112a Bottom cover sheet 112 Second edge 112b Support units 113, 114 Third edge 112c Chamfer 114a Fourth edge 112d

[0025] Preferred embodiments of the present invention

[0026] In order to make the above-mentioned objectives, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below with reference to the accompanying drawings.

[0027] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0028] As used in this application and the claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not intended to refer to the singular but may include the plural. Generally speaking, the terms "comprises" and "include" only indicate the inclusion of the steps and elements specifically identified, and these steps and elements do not constitute an exclusive list. A method or apparatus may also include other steps or elements.

[0029] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is solely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. Furthermore, while the terms used in this application are selected from commonly known and commonly used terms, some terms mentioned in this specification may have been selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant sections of this description. Furthermore, this application should be understood not only by the actual terms used, but also by the meaning implied by each term.

[0030] Next, the Mylar film for lithium batteries and the lithium batteries of the present application are described through specific examples.

[0031] FIG1 is a schematic three-dimensional diagram of a Mylar film for a lithium battery according to an embodiment. As shown in FIG1 , the Mylar film 110 can be folded into a boxed structure, which is used to wrap the battery cell and prevent the battery cell from contacting the shell (e.g., an aluminum shell) and causing a short circuit. The bottom of the box-shaped structure has four corners 111, and the aluminum shell has four corners corresponding to the four corners 111. In conventional technology, in order to prevent the Mylar film from rupturing due to contact between the corners 111 of the box-shaped structure and the corners of the aluminum shell, a bottom support plate is provided between the bottom of the box-shaped structure and the aluminum shell to prevent the corners 111 of the box-shaped structure from contacting the corners of the aluminum shell. However, the bottom support plate increases manufacturing costs and increases the number of steps in the battery assembly process, thereby reducing production efficiency.

[0032] Figure 2 is a schematic side view of a Mylar film for a lithium battery according to one embodiment, and Figure 3 is a schematic rear view of a Mylar film for a lithium battery according to one embodiment. Figure 2 can be considered a schematic side view of the box-like structure in Figure 1, and Figure 3 can be considered a schematic rear view of the box-like structure in Figure 1. Referring to Figures 2 and 3, the bottom cover sheet 112 of the Mylar film 110 includes a plurality of support units 113, which are disposed between the bottom cover sheet 112 and the housing containing the Mylar film 110. The number of support units 113 can be set as needed and is not limited to the number shown in Figure 2.

[0033] As shown in FIG2 , a plurality of support units 113 are spaced apart along the second direction D2. Adjacent support units 113 are spaced apart by a distance d1 in the second direction D2. This application does not limit the distance d1; for example, the distance d1 may be less than, equal to, or greater than the size of the support unit 113 in the second direction D2.

[0034] The support units 113 have a height h1 in the third direction D3. Height h1 is equal to or greater than 0.5 mm. Limiting height h1 to 0.5 mm or greater ensures that corners 111 of the box-shaped structure in FIG1 do not contact the housing, thereby preventing damage to the Mylar film. The support units 113 are all of equal height, ensuring uniform force distribution across each support unit 113. It should be understood that, due to manufacturing processes and other factors, certain height differences between support units 113 are permitted. For example, if the difference between support units 113 is less than 10% of the height h1 of support unit 113, the support units 113 can still be considered equal in height.

[0035] In addition to the support unit 113 shown in Figures 2 and 3, the present application also provides another support unit. Refer to Figure 4 for a top view schematic diagram of a Mylar film for a lithium battery according to another embodiment, and Figure 5 for a rear view schematic diagram of a Mylar film for a lithium battery according to another embodiment. A plurality of support units 114 are provided on the bottom covering sheet 112 and are arranged at intervals along the first direction D1. The present application does not limit the number of support units 114, which is not limited to 9 as shown in Figure 4, and the number of support units 114 can be increased or decreased as needed. The present application also does not limit the distance between adjacent support units 114 along the first direction D1.

[0036] As shown in Figure 4 , support units 114 have a height h2 in the first direction D1. Height h2 is equal to or greater than 0.5 mm. Limiting height h2 to 0.5 mm ensures that corners 111 of the box-shaped structure in Figure 1 do not contact the housing, thereby preventing damage to the Mylar film. The support units 114 are all the same height, ensuring uniform force is applied to each support unit 114. It should be understood that, due to manufacturing processes and other factors, certain height differences between support units 114 are permitted. For example, if the difference between support units 114 is less than 10% of the height h2 of support unit 113, the support units 114 can still be considered to be of the same height.

[0037] As shown in Figures 4 and 5 , each support unit 114 has a chamfer 114a perpendicular to the side of the bottom cover sheet 112. In Figure 5 , the chamfer 114a is a rounded chamfer; in other embodiments, the chamfer 114a may also be an oblique chamfer. The chamfer 114a helps reduce stress concentration.

[0038] In one embodiment, the method of manufacturing the support unit 113 and the support unit 114 includes stamping. For example, the bottom cover sheet 112 may be stamped to form the support unit 113 and the support unit 114. The stamping process has the advantages of low cost and high speed.

[0039] As shown in FIG5 , in one embodiment, the bottom cover sheet 112 has a first edge 112a, a second edge 112b, a third edge 112c, and a fourth edge 112d. The distance between each support unit 114 and the first edge 112a, the second edge 112b, the third edge 112c, and the fourth edge 112d is greater than a preset distance. The preset distance ensures that each support unit 114 does not contact the corner of the shell. In other words, the distance between each support unit 114 and the first edge 112a, the second edge 112b, the third edge 112c, and the fourth edge 112d ensures that the top surface 114b of each support unit 114 is completely in contact with the bottom cover sheet 112. In this way, the support unit 114 can be prevented from cracking due to uneven force.

[0040] In the aforementioned embodiments of the present application, by providing a support unit on the bottom cover sheet of the Mylar film, contact between the Mylar film and the corners of the housing is avoided, thereby preventing the Mylar film from rupturing and causing a battery short circuit. Furthermore, compared to technical solutions that provide a bottom support plate between the bottom cover sheet and the housing to prevent contact between the Mylar film and the corners, the bottom cover sheet of the present application has its own support unit, thus eliminating the need for a bottom support plate. This reduces production costs and eliminates the need to install the bottom support plate during battery assembly, thereby improving production efficiency.

[0041] On the other hand, the present application also proposes a lithium battery, which includes: a battery cell, a shell and the Mylar film as described above. The Mylar film covers the battery cell, the battery cell covered with the Mylar film is located in the shell, and the support unit in the Mylar film is arranged between the bottom covering sheet and the shell. The present application also proposes an electronic product, which includes the lithium battery as described above. The lithium battery in the above embodiment of the present application avoids contact between the Mylar film and the corners of the shell by providing a support unit on the bottom covering sheet of the Mylar film, thereby avoiding the Mylar film from rupturing and causing a battery short circuit.

[0042] The basic concepts have been described above. It will be apparent to those skilled in the art that the above disclosures are merely examples and do not limit the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and revisions to the present application. Such modifications, improvements, and revisions are suggested in the present application and remain within the spirit and scope of the exemplary embodiments of the present application.

[0043] At the same time, this application uses specific terms to describe the embodiments of this application. For example, "one embodiment," "an embodiment," and / or "some embodiments" refer to a certain feature, structure, or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that "one embodiment," "an embodiment," or "an alternative embodiment" mentioned twice or multiple times in different locations in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this application may be appropriately combined.

[0044] In some embodiments, numbers are used to describe the quantity of components and attributes. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise stated, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the description and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the settings of such numerical values ​​are as accurate as possible within the feasible range.

Claims

1. A Mylar film for lithium battery, characterized in that: The bottom covering sheet of the Mylar film has a plurality of supporting units, and the plurality of supporting units are arranged between the bottom covering sheet and a shell accommodating the Mylar film.

2. The Mylar film according to claim 1, characterized in that The plurality of support units are arranged at intervals along the first direction.

3. The Mylar film according to claim 1, characterized in that Each of the supporting units has a chamfered side perpendicular to the bottom covering sheet.

4. The Mylar film according to claim 1, characterized in that The plurality of support units are arranged at intervals along the second direction.

5. The Mylar film according to claim 2 or 4, characterized in that: The plurality of support units are formed by the bottom covering sheet through a stamping process.

6. The Mylar film according to claim 1, characterized in that The height of each of the support units is equal to or greater than 0.5 mm.

7. The Mylar film according to claim 1, characterized in that The height of each of the support units is the same.

8. The Mylar film according to claim 1, wherein A distance between the supporting unit and an edge of the bottom covering sheet is greater than a preset distance.

9. A lithium battery, characterized in that: include: Battery cells; The Mylar film for lithium battery according to any one of claims 1 to 8, wherein the Mylar film for lithium battery covers the battery cell; and The shell includes a Mylar film-wrapped battery cell located inside the shell, wherein the support unit in the Mylar film for the lithium battery is disposed between the bottom wrapping sheet and the shell.

10. An electronic product, characterized in that: include: The lithium battery as claimed in claim 9.

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