Protective film and protective structure

Abstract

The utility model provides a protective film and a protective structure, the protective film is used for covering the surface of an alkali metal foil and comprises a film main body and a plurality of bulges arranged on one side of the film main body, and the film main body is contacted with the alkali metal foil through the bulges. According to the protective film, the alkali metal foil can be protected, the structure is simple, the protrusions are arranged on the film body, the film body is in contact with the alkali metal foil through the protrusions, the contact area of the alkali protective film and the alkali metal foil can be reduced, and therefore the damage degree to the alkali metal foil is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of alkali metal batteries, and in particular to a protective film. Meanwhile, the utility model also relates to a protective structure having the protective film. Background Art

[0002] In recent years, in order to meet the society's growing demand for energy density in energy storage systems, alkali metal negative electrodes (Li, Na, K) have become a research hotspot due to their high specific capacity (3861, 1166, 685 mAh g-1) and low redox potential relative to the standard hydrogen electrode potential (-3.01, -2.71, -2.93 V). As the negative electrode of alkali metal batteries, metal foil generally needs to be stored in an anhydrous and oxygen-free environment before being prepared into alkali metal batteries, so the alkali metal foil needs to be protected by a protective structure. However, the existing protective structure is limited by its own structure. When it is removed from the alkali metal foil, the metal on the surface of the alkali metal foil will be adsorbed onto the protective structure, thereby damaging the surface of the alkali metal foil, resulting in an uneven surface and affecting the uniform deposition of alkali metal ions during subsequent charging and discharging. Utility Model Content

[0003] In view of this, the utility model aims to provide a protective film to protect the alkali metal foil and reduce the degree of damage to the alkali metal foil.

[0004] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0005] A protective film is used to cover the surface of an alkali metal foil, comprising a film body and a plurality of protrusions arranged on one side of the film body, wherein the film body contacts the alkali metal foil through the protrusions.

[0006] Furthermore, the plurality of protrusions are evenly distributed on the surface of the membrane body, and the distance between two adjacent protrusions is 5 mm-200 mm.

[0007] Furthermore, the thickness of the membrane body is between 0.001 mm and 5 mm.

[0008] Compared with the prior art, the utility model has the following advantages:

[0009] The protective film described in the utility model can protect the alkali metal foil while having a simple structure. By providing a protrusion on the film body and making the film body contact with the alkali metal foil through the protrusion, the contact area between the alkali protective film and the alkali metal foil can be reduced, thereby reducing the degree of damage to the alkali metal foil.

[0010] Another object of the utility model is to provide a protective structure, comprising the protective films as described above respectively used to cover both sides of the alkali metal foil, at least one of the protective films is provided with a glue strip for bonding with the other protective film.

[0011] Further, the membrane body is in a rectangular shape;

[0012] The length and / or width of the membrane body is between 10 mm and 2000 mm.

[0013] Furthermore, the rubber strip is arranged on a side of the membrane body where the protrusion is arranged;

[0014] The rubber strip is arranged close to the edge of the membrane body and extends circumferentially along the membrane body.

[0015] Furthermore, the rubber strips are provided on the protective films on both sides, and the thickness of the rubber strips is greater than the height of the protrusions.

[0016] Furthermore, the height H1 of the protrusion satisfies: 0.001 mm ≤ H1 ≤ 5 mm; and / or,

[0017] The height H1 of the protrusion and the thickness H2 of the rubber strip satisfy:

[0018] 0.01mm≤H2-H1≤15mm.

[0019] Furthermore, the width of the rubber strip is between 0.5 mm and 100 mm.

[0020] Furthermore, the membrane body is provided with a hand-tear portion extending in a direction away from the membrane body.

[0021] Compared with the prior art, the utility model has the following advantages:

[0022] The protective structure described in the utility model is provided with a protective film for covering both sides of the alkali metal foil, which is beneficial to reducing the damage to the alkali metal foil. At the same time, by providing a rubber strip for bonding the protective films on both sides, it is convenient to package the alkali metal foil in the space between the protective films on both sides, isolate the air, reduce the oxidation of the surface of the alkali metal foil, and facilitate the storage of the alkali metal foil.

[0023] In addition, by providing adhesive strips on the protective films on both sides and making the thickness of the adhesive strips greater than the height of the protrusions, it is convenient to leave enough space for accommodating the alkali metal foil between the protective films on both sides after the protective films on both sides are bonded, thereby facilitating the storage of the alkali metal foil.

[0024] In addition, by providing a hand-tear portion, when the alkali metal foil needs to be taken out, the protective films on both sides can be separated by pulling the hand-tear portion, and then the alkali metal foil can be taken out, which has a simple structure and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the accompanying drawings:

[0026] Figure 1 A top view of the protective film according to an embodiment of the utility model;

[0027] Figure 2 It is a front view of the protective film described in the embodiment of the utility model;

[0028] Figure 3 This is a schematic structural diagram of the protection structure according to an embodiment of the utility model before encapsulating the alkali metal foil;

[0029] Figure 4 This is a schematic structural diagram of the protective structure described in an embodiment of the utility model after the alkali metal foil is packaged.

[0030] Description of reference numerals:

[0031] 1. Film body; 2. Protrusion; 3. Adhesive strip; 4. Alkali metal foil; 5. Hand-tear portion. DETAILED DESCRIPTION

[0032] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0033] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0034] In addition, in the description of the present invention, unless otherwise clearly defined, the terms "installation", "connection", "connection", and "connector" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood in combination with specific circumstances.

[0035] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0036] Embodiment 1

[0037] This embodiment relates to a protective film for covering the surface of an alkali metal foil 4, such as Figure 1 and Figure 2 As shown in the figure, the protective film includes a film body 1 and a plurality of protrusions 2 provided on one side of the film body 1, and the film body 1 contacts the alkali metal foil 4 through the protrusions 2. It can be understood that the protective film of this embodiment, after covering the surface of the alkali metal foil 4, can protect the alkali metal foil 4 while having a simple structure, and by providing the protrusions 2 on the film body 1 and making the film body 1 contact the alkali metal foil 4 through the protrusions 2, the contact area between the alkali protective film and the alkali metal foil 4 can be reduced, thereby reducing the degree of damage to the alkali metal foil 4.

[0038] Based on the above overall introduction, as a preferred implementation, in this embodiment, a plurality of protrusions 2 are evenly distributed on the surface of the membrane body 1, and the distance between two adjacent protrusions 2 is 5mm-200mm, which can be specifically 5mm, 10mm, 50mm, 100mm and 200mm, etc. By evenly distributing the protrusions 2 on the surface of the membrane body 1 and setting the distance between the protrusions 2 within the above range, it is beneficial to support the membrane body 1 through the protrusions 2, and prevent the large surface of the membrane body 1 from contacting the alkali metal foil 4.

[0039] It should be noted that the protective film in this embodiment can be made by rolling a release film in the prior art, and a roller for rolling the release film can be provided with a uniform portion of a convex structure, so that the convexity 2 can be formed on the release film during the rolling process of the release film. The release film can be made of a polymer material commonly used in the prior art, such as thermoplastic polyester, polyethylene, polypropylene, etc.

[0040] As a preferred implementation manner, in this embodiment, the thickness of the membrane body 1 is between 0.001mm-5mm, and specifically can be 0.001mm, 0.005mm, 0.1mm, 1mm, 3mm and 5mm, etc. By making the membrane body 1 within the above-mentioned thickness range, the strength of the protective film is ensured, the thickness of the protective film is smaller, and the cost is lower.

[0041] The protective film of this embodiment can protect the alkali metal foil 4 while having a simple structure. By providing a protrusion 2 on the film body 1 and making the film body 1 contact with the alkali metal foil 4 through the protrusion 2, the contact area between the alkali protective film and the alkali metal foil 4 can be reduced, thereby reducing the degree of damage to the alkali metal foil 4.

[0042] Embodiment 2

[0043] This embodiment relates to a protective structure. In terms of overall structure, the protective structure includes protective films of the first embodiment respectively covering both sides of the alkali metal foil 4, and at least one of the protective films is provided with a rubber strip 3 for bonding with the other protective film. It can be understood that, if Figure 3 and Figure 4 As shown in the figure, by making the protective structure include protective films respectively used to cover the two sides of the alkali metal foil 4, it is beneficial to reduce the degree of damage to the alkali metal foil 4. At the same time, by providing a glue strip 3 for bonding the protective films on both sides, it is convenient to encapsulate the alkali metal foil 4 in the space between the protective films on both sides, isolate the air, reduce the oxidation of the surface of the alkali metal foil 4, and facilitate the storage of the alkali metal foil.

[0044] As a preferred implementation method, Figure 1 As shown in the figure, in this embodiment, the membrane body 1 is rectangular, and the length and width of the membrane body 1 are between 10 mm and 2000 mm, and the length and width of the membrane body 1 can be specifically 10 mm, 100 mm, 1000 mm, and 2000 mm, etc., so that the structure is simple, and it is convenient for the protective film to cover the surface of the alkali metal foil 4. Of course, in this embodiment, the length and width of the membrane body 1 are both set within the above-mentioned size range, which is only a preferred embodiment. In addition, in other embodiments, the length or width of the membrane body 1 can also be set to other sizes.

[0045] As a preferred embodiment, Figure 1 As shown in the figure, in this embodiment, the rubber strip 3 is arranged on the side of the membrane body 1 where the protrusion 2 is arranged, and the rubber strip 3 is arranged close to the edge of the membrane body 1 and extends along the circumference of the membrane body 1. Such an arrangement has a simple structure, which is convenient for bonding two protective films and also convenient for the packaging operation of the alkali metal foil 4. In specific operation, the alkali metal foil 4 can be placed on a protective film at a position inside the annular rubber strip 3, and then another protective film is covered on the alkali metal foil 4, and the protective films on both sides are bonded by the rubber strip 3.

[0046] As a preferred implementation method, Figure 3 and Figure 4 As shown in the figure, adhesive strips 3 are provided on the protective films on both sides, and the thickness of the adhesive strips 3 is greater than the height of the protrusions 2. Such a configuration makes it easy to leave enough space for accommodating the alkali metal foil 4 between the protective films on both sides after the protective films on both sides are bonded, so as to facilitate the storage of the alkali metal foil 4.

[0047] As a preferred implementation, in this embodiment, the height H1 of the protrusion 2 satisfies: 0.001mm≤H1≤5mm, and the height H1 of the protrusion 2 and the thickness H2 of the rubber strip 3 satisfy: 0.01mm≤H2-H1≤15mm. In specific implementation, the height H1 of the protrusion 2 can be 0.001mm, 0.005mm, 0.1mm, 1mm, 3mm, and 5mm, etc. And the difference between the thickness H2 of the rubber strip 3 and the height H1 of the protrusion 2 can be 0.01mm, 1mm, 5mm, 10mm, and 15mm, etc. This arrangement makes it easy to use less rubber strip 3 while leaving enough space between the protective films on both sides to accommodate the alkali metal foil 4.

[0048] It should be noted that, in the present embodiment, the height H1 of the protrusion 2 and the difference between the thickness H2 of the rubber strip 3 and the height H1 of the protrusion 2 are set within the above-mentioned size range only as a preferred implementation. In addition, in other embodiments, the height H1 of the protrusion 2 or the thickness H2 of the rubber strip 3 and the height H1 of the protrusion 2 can also be set to other sizes.

[0049] As a preferred embodiment, in this embodiment, the width of the rubber strip 3 is between 0.5mm-100mm, and can be specifically 0.5mm, 1mm, 10mm, 50mm, and 100mm, etc. By setting the width of the rubber strip 3 within the above range, it is convenient to ensure the bonding strength between the protective films on both sides while reducing the amount of adhesive used and reducing costs.

[0050] In addition, as preferably, Figure 1 As shown in FIG, a hand-tear portion 5 extending away from the membrane body 1 is provided on the membrane body 1. Specifically, the hand-tear portion 5 can be a sheet-like structure formed integrally with the membrane body 1 and extending outward. When the alkali metal foil 4 needs to be taken out, the protective films on both sides can be separated by pulling the hand-tear portion 5, and then the alkali metal foil 4 can be taken out. The structure is simple and the operation is convenient.

[0051] The protective structure of this embodiment is provided with a protective film for covering both sides of the alkali metal foil 4, which helps to reduce the degree of damage to the alkali metal foil 4. At the same time, by providing a rubber strip 3 for bonding the protective films on both sides, it is convenient to encapsulate the alkali metal foil 4 in the space between the protective films on both sides, isolate the air, reduce the oxidation of the surface of the alkali metal foil 4, and facilitate the storage of the alkali metal foil 4.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A protective film for covering the surface of an alkali metal foil, characterized in that: The invention comprises a film body and a plurality of protrusions arranged on one side of the film body, wherein the film body contacts the alkali metal foil through the protrusions.

2. The protective film according to claim 1, characterized in that: The plurality of protrusions are evenly distributed on the surface of the membrane body, and the distance between two adjacent protrusions is 5 mm-200 mm.

3. The protective film according to claim 1, characterized in that: The thickness of the membrane body is between 0.001 mm and 5 mm.

4. A protective structure, characterized in that: The invention comprises protective films according to any one of claims 1 to 3 respectively used to cover both sides of the alkali metal foil, wherein at least one of the protective films is provided with a glue strip for bonding with the other protective film.

5. The protective structure according to claim 4, characterized in that: The membrane body is in a rectangular shape; The length and / or width of the membrane body is between 10 mm and 2000 mm.

6. The protective structure according to claim 5, characterized in that: The rubber strip is arranged on one side of the membrane body where the protrusion is arranged; The rubber strip is arranged close to the edge of the membrane body and extends along the circumference of the membrane body.

7. The protective structure according to claim 6, characterized in that: The rubber strips are provided on the protective films on both sides, and the thickness of the rubber strips is greater than the height of the protrusions.

8. The protective structure according to claim 7, characterized in that: The height H1 of the protrusion satisfies: 0.001 mm ≤ H1 ≤ 5 mm; and / or, the height H1 of the protrusion and the thickness H2 of the rubber strip satisfy: 0.01mm≤H2-H1≤15mm.

9. The protective structure according to claim 7, characterized in that: The width of the rubber strip is between 0.5 mm and 100 mm.

10. The protective structure according to claim 7, characterized in that: The film body is provided with a hand-tear portion extending in a direction away from the film body.

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