Aluminum battery packaging film

Abstract

An aluminum battery packaging film includes a heat seal layer, wherein the material of the heat seal layer includes modified polyethylene terephthalate, polycarbonate, polyimide, or a combination thereof.

Description

Technical Field

[0001] This invention relates to a packaging film, and more particularly to an aluminum battery packaging film. Background Technology

[0002] Compared to other batteries (such as lithium batteries), aluminum batteries have much stricter requirements for their packaging films. Furthermore, the composition of aluminum batteries makes their heat-sealing layer susceptible to corrosion and dissolution by the electrolyte within a short period, leading to leakage and affecting the battery's safety and lifespan. Therefore, designing a packaging film that improves the safety and lifespan of aluminum batteries is a significant challenge. Summary of the Invention

[0003] This invention provides an aluminum battery packaging film that can improve the safety and lifespan of aluminum batteries.

[0004] The present invention provides an aluminum battery packaging film, comprising a heat-sealing layer, wherein the material of the heat-sealing layer comprises modified polyethylene terephthalate, polycarbonate, polyimide, or a combination thereof.

[0005] In one embodiment of the present invention, the above-mentioned modified polyethylene terephthalate is formed by co-extrusion of crystalline and amorphous forms.

[0006] In one embodiment of the present invention, the mechanical strength of the heat-sealing layer is at least greater than 3 kgf.

[0007] In one embodiment of the present invention, the thickness of the heat-sealing layer is between 25 micrometers (μm) and 150 micrometers.

[0008] In one embodiment of the present invention, the above-described aluminum battery packaging film is configured to package an aluminum battery containing an acidic electrolyte.

[0009] In one embodiment of the present invention, the material of the heat-sealing layer does not include polypropylene.

[0010] In one embodiment of the present invention, a first adhesive layer, a metal layer, a second adhesive layer, and a polymer material layer are sequentially stacked on the heat-sealing layer.

[0011] In one embodiment of the present invention, the metal layer is made of aluminum, and the polymer layer is made of nylon or polyethylene terephthalate.

[0012] In one embodiment of the present invention, the thickness of the polymer material layer is between 10 micrometers and 40 micrometers.

[0013] In one embodiment of the present invention, the thickness of the metal layer is between 20 micrometers and 60 micrometers.

[0014] Based on the above, the aluminum battery packaging film of the present invention selects modified polyethylene terephthalate, polycarbonate, polyimide or a combination thereof with corrosion-resistant properties to form the heat-sealing layer. In this way, the problem of easy corrosion of the heat-sealing layer of the aluminum battery packaging film in the electrolyte can be improved, and the occurrence of aluminum battery breakage and leakage can be reduced, thus improving the safety and life of aluminum batteries.

[0015] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings. Attached Figure Description

[0016] Figure 1 This is a partial cross-sectional schematic diagram of an aluminum battery packaging film according to an embodiment of the present invention;

[0017] Figure 2 This is a schematic diagram showing the mechanical strength of a heat-sealing layer of an aluminum battery packaging film according to an embodiment of the present invention at different speeds versus temperature. Detailed Implementation

[0018] Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same element references are used in the drawings and description to denote the same or similar parts.

[0019] To facilitate a better understanding of the invention, specific embodiments are provided below as examples of how the invention can be practiced. For clarity, numerous practical details will be described in the following description. However, it should be understood that these practical details are not intended to limit the invention. In other words, these practical details are not essential in some embodiments of the invention.

[0020] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0021] It should be understood that although the terms “first,” “second,” “third,” etc., may be used herein to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, and / or parts should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer, or part from another. Therefore, “first element,” “component,” “region,” “layer,” or “part” discussed below may be referred to as a second element, component, region, layer, or part without departing from the teachings of this document.

[0022] Figure 1 This is a partial cross-sectional schematic diagram of an aluminum battery packaging film according to an embodiment of the present invention. Figure 2 This is a schematic diagram showing the mechanical strength of a heat-sealing layer of an aluminum battery packaging film according to an embodiment of the present invention at different speeds versus temperature.

[0023] Please refer to Figure 1 and Figure 2 The aluminum battery packaging film 100 of this embodiment includes a heat-sealing layer 110. The heat-sealing layer 110 of the aluminum battery packaging film 100 of this embodiment is made by selecting modified polyethylene terephthalate (PET), polycarbonate (PC), polyimide (PI) or a combination thereof with corrosion-resistant properties. In this way, the problem of easy corrosion of the heat-sealing layer 110 of the aluminum battery packaging film 100 in the electrolyte can be improved, and the occurrence of aluminum battery breakage and leakage can be reduced, thereby improving the safety and life of the aluminum battery. Furthermore, since the aluminum battery packaging film 100 of this embodiment is made of modified polyethylene terephthalate, polycarbonate, polyimide or a combination thereof with corrosion-resistant properties to form the heat-sealing layer 110, the aluminum battery packaging film 100 of this embodiment has high corrosion resistance, barrier properties and heat-sealing properties. This allows the aluminum battery packaging film 100 of this embodiment to withstand long-term contact with electrolyte during rapid charging and discharging and high cycle counts without leakage or breakage, thereby enhancing the safety of aluminum battery use and increasing its service life.

[0024] In some embodiments, since crystalline polyethylene terephthalate has poor heat-sealing properties, while amorphous polyethylene terephthalate has better heat-sealing properties, crystalline polyethylene terephthalate has the function of blocking oxygen and vapor. Therefore, the modified polyethylene terephthalate of this embodiment can be formed by co-extrusion of crystalline and amorphous polyethylene terephthalate, so that the aluminum battery packaging film 100 of this embodiment can simultaneously have the properties of heat sealing and gas barrier. The crystalline polyethylene terephthalate can be the outer layer structure, and the amorphous polyethylene terephthalate can be the inner layer structure. However, the present invention is not limited to this, and the modified polyethylene terephthalate can be formed by other suitable modification methods.

[0025] Furthermore, the aforementioned polycarbonate and polyimide can be either unmodified or modified materials. For example, suitable long-chain compounds or highly polar functional groups can be used to modify polycarbonate, and co-extrusion can be used to modify polyimide to make it heat-sealing. However, the present invention is not limited thereto.

[0026] In some embodiments, by Figure 2Therefore, the heat-sealing layer 110 can achieve different mechanical strengths at different temperatures (200–240°C) and speeds (3.8 m / min and 4 m / min). Figure 2 A favorable range of mechanical strength can be obtained. For example, the mechanical strength of the heat-sealing layer 110 can be at least greater than 3 kgf, and no leakage or rupture occurs after a one-day expansion test under this favorable mechanical strength. However, the invention is not limited to this. Figure 2 The aluminum battery packaging film is made using a heat-sealing layer of modified polyethylene terephthalate material. The expansion test involves injecting the aluminum battery packaging film with electrolyte and then creating a vacuum (approximately -1 atmosphere) to test its ability to withstand pressure changes. Furthermore, the electrolyte can be an acidic electrolyte; therefore, the aluminum battery packaging film 100 of this embodiment can be configured to package aluminum batteries containing acidic electrolytes, but the invention is not limited thereto.

[0027] It should be noted that the present invention does not limit the type and specifications of the aluminum batteries (such as positive electrode, negative electrode, separator and electrolyte, etc.) covered by the aluminum battery packaging film 100. The type and specifications of the aluminum batteries can be obtained by a person skilled in the art based on any content that covers the spirit and scope of the appended patent application.

[0028] In some embodiments, the thickness of the heat-sealing layer 110 is between 25 micrometers (μm) and 150 micrometers, but the present invention is not limited thereto, and the thickness of the heat-sealing layer 110 can be adjusted according to the actual design requirements.

[0029] In some embodiments, since polypropylene (PP) has poor corrosion resistance, the material of the heat-sealing layer 110 in this embodiment does not include polypropylene. In other words, the heat-sealing layer 110 in this embodiment can be replaced by modified polyethylene terephthalate, polycarbonate, polyimide and other materials to make the aluminum battery packaging film 100 have better corrosion resistance, barrier properties and heat-sealing properties, but the present invention is not limited thereto.

[0030] In some embodiments, a first adhesive layer 120, a metal layer 130, a second adhesive layer 140, and a polymer material layer 150 are sequentially stacked on the heat-sealing layer 110. The first adhesive layer 120 and the second adhesive layer 140 can be made of polyurethane (PU), the metal layer 130 can be made of aluminum, and the polymer material layer 150 can be made of nylon or polyethylene terephthalate. Furthermore, the thickness of the first adhesive layer 120 is between 1 micrometer and 10 micrometers, the thickness of the metal layer 130 is between 20 micrometers and 60 micrometers, the thickness of the second adhesive layer 140 is between 1 micrometer and 10 micrometers, and the thickness of the polymer material layer 150 is between 10 micrometers and 40 micrometers. However, the invention is not limited to these dimensions; the materials and thicknesses of the first adhesive layer 120, the metal layer 130, the second adhesive layer 140, and the polymer material layer 150 can be selected according to actual design requirements.

[0031] The aluminum battery packaging films made with heat-sealing layers of different materials were cut into 1 cm x 5 cm sizes and placed in an acidic electrolyte. Then, they were placed in an oven at room temperature and 80°C for aging tests. The results are detailed in Table 1, and the following conclusions were drawn: Compared with polypropylene as the heat-sealing layer material, modified polyethylene terephthalate, polycarbonate, and polyimide as the heat-sealing layer materials can have better corrosion resistance.

[0032] Table 1

[0033] Modified ethylene terephthalate No corrosion for more than 120 days 60 days (corrosion) polycarbonate No corrosion for more than 120 days 40 days (corrosion) polyimide No corrosion for more than 30 days No corrosion for more than 30 days polypropylene Dissolves in 5 days Dissolves in 3 days

[0034] In summary, because the aluminum battery packaging film of the present invention uses modified polyethylene terephthalate, polycarbonate, polyimide, or a combination thereof with corrosion-resistant properties to form the heat-sealing layer, the aluminum battery packaging film of the present invention has high corrosion resistance, barrier properties, and heat-sealing performance. This allows the aluminum battery packaging film of the present invention to withstand prolonged contact with electrolyte during rapid charging and discharging and high cycle counts without leakage or breakage, thereby enhancing the safety of aluminum battery use and increasing its service life.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A packaging film for aluminum batteries, characterized in that, include: A heat-sealing layer, wherein the material of the heat-sealing layer is composed of modified polyethylene terephthalate, the modified polyethylene terephthalate comprising crystalline polyethylene terephthalate and amorphous polyethylene terephthalate, the crystalline polyethylene terephthalate being the outer layer structure and the amorphous polyethylene terephthalate being the inner layer structure; and A first adhesive layer, a metal layer, a second adhesive layer, and a polymer material layer are sequentially stacked on the heat-sealing layer.

2. The aluminum battery packaging film according to claim 1, characterized in that, The modified polyethylene terephthalate is formed by co-extrusion of the crystalline polyethylene terephthalate and the amorphous polyethylene terephthalate.

3. The aluminum battery packaging film according to claim 1, characterized in that, The mechanical strength of the heat-sealing layer is at least greater than 3 kgf.

4. The aluminum battery packaging film according to claim 1, characterized in that, The thickness of the heat-sealing layer is between 25 micrometers and 150 micrometers.

5. The aluminum battery packaging film according to claim 1, characterized in that, The aluminum battery packaging film is configured to package aluminum batteries containing acidic electrolyte.

6. The aluminum battery packaging film according to claim 1, characterized in that, The metal layer is made of aluminum, while the polymer layer is made of nylon or polyethylene terephthalate.

7. The aluminum battery packaging film according to claim 1, characterized in that, The thickness of the polymer material layer is between 10 micrometers and 40 micrometers.

8. The aluminum battery packaging film according to claim 1, characterized in that, The thickness of the metal layer is between 20 micrometers and 60 micrometers.

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