Puncture-resistant lithium battery outer envelope and production process thereof

Abstract

The application discloses a kind of puncture-resistant lithium battery outer film and its production process, belong to lithium battery technical field, including puncture-resistant layer, insulating protective layer and substrate bottom layer, puncture-resistant layer is connected on insulating protective layer, insulating protective layer is connected on substrate bottom layer.The application solves the problem that existing lithium battery outer film is poor in puncture resistance when in use, leading to lithium battery is easily damaged, reduces the service life of lithium battery, the application adopts polyurethane fiber and polypropylene fiber to produce longitudinal blocking body and transverse blocking body, and longitudinal blocking body and transverse blocking body are set in puncture-resistant matrix in vertical and horizontal interlaced, can make the puncture-resistant layer formed by puncture-resistant matrix, longitudinal blocking body and transverse blocking body have higher strength, resilience and wear resistance, can improve the puncture resistance of lithium battery outer film formed by puncture-resistant layer, insulating protective layer and substrate bottom layer, prevent lithium battery from being damaged, can improve the service life of lithium battery.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of lithium batteries, in particular to a puncture-resistant lithium battery outer film and a production process thereof. BACKGROUND

[0002] A lithium battery is a battery using a lithium metal or a lithium alloy as a positive / negative electrode material and using a nonaqueous electrolyte solution; in 1912, the lithium metal battery was first proposed and researched by Gilbert N. Lewis; in the 1970s, M.S. Whittingham proposed and started to research the lithium ion battery. Due to the very active chemical properties of the lithium metal, the processing, preservation and use of the lithium metal have very high requirements on the environment. With the development of science and technology, the lithium battery has become mainstream.

[0003] The lithium battery can be roughly divided into two categories: a lithium metal battery and a lithium ion battery; the lithium ion battery does not contain lithium in a metal state and is chargeable; the fifth-generation product of the chargeable battery, the lithium metal battery, was born in 1996, and has better safety, specific capacity, self-discharge rate and performance-price ratio than the lithium ion battery.

[0004] When the lithium battery is used, an outer film is usually arranged on the lithium battery for protecting the lithium battery; the existing lithium battery outer film has poor puncture resistance when used, so that the lithium battery is easily damaged, and the service life of the lithium battery is reduced. SUMMARY

[0005] The application aims to provide a puncture-resistant lithium battery outer film and a production process thereof, which can improve the puncture resistance of the lithium battery outer film formed by a puncture-resistant layer, an insulating protective layer and a substrate bottom layer, prevent the lithium battery from being damaged, improve the service life of the lithium battery and solve the problems in the background art.

[0006] To achieve the above-mentioned purpose, the application provides the following technical scheme.

[0007] A puncture-resistant lithium battery outer film comprises a puncture-resistant layer, an insulating protective layer and a substrate bottom layer, the puncture-resistant layer is connected to the surface of the insulating protective layer through an adhesive, and the insulating protective layer is connected to the surface of the substrate bottom layer through an adhesive, wherein the thickness ratio of the puncture-resistant layer, the insulating protective layer and the substrate bottom layer is 0.8-1.2:1:0.3.

[0008] Preferably, the puncture-resistant layer comprises a puncture-resistant substrate, and the puncture-resistant substrate is made of high-density polyethylene material.

[0009] Preferably, the puncture-resistant layer further comprises a longitudinal blocking body and a transverse blocking body, the longitudinal blocking body is connected to the transverse blocking body, and the longitudinal blocking body and the transverse blocking body are distributed in the puncture-resistant substrate in a longitudinal and transverse staggered manner.

[0010] Preferably, the puncture-resistant base is provided with an assembly groove for the longitudinal and transverse blocking bodies, and both ends of the longitudinal and transverse blocking bodies are connected to the groove wall of the assembly groove.

[0011] Preferably, the longitudinal and transverse blocking bodies each comprise the following raw materials in mass fraction: 20-36 parts of polyurethane fiber and 16-32 parts of polypropylene fiber.

[0012] Preferably, the insulating protective layer comprises a waterproof layer, a heat insulation layer, a corrosion-resistant layer and an insulating layer, the waterproof layer is arranged on the heat insulation layer, the heat insulation layer is arranged on the corrosion-resistant layer, and the corrosion-resistant layer is arranged on the insulating layer.

[0013] Preferably, the base substrate is made of polyethylene terephthalate material.

[0014] According to another aspect of the present application, there is provided a production process of a puncture-resistant lithium battery outer film, comprising the following steps:

[0015] S1, producing a puncture-resistant layer:

[0016] The longitudinal and transverse blocking bodies are processed by polyurethane fiber and polypropylene fiber, the puncture-resistant base is processed by high-density polyethylene, and the longitudinal and transverse blocking bodies are assembled in the puncture-resistant base in a longitudinal and transverse interlaced manner to form the puncture-resistant layer.

[0017] S2, producing an insulating protective layer:

[0018] The waterproof layer is connected to the heat insulation layer by using an adhesive, the heat insulation layer is connected to the corrosion-resistant layer, and the corrosion-resistant layer is connected to the insulating layer, and then co-extrusion flow casting and stretching are performed to form the insulating protective layer.

[0019] S3, producing a base substrate:

[0020] The base substrate is processed by polyethylene terephthalate to form the base substrate.

[0021] S4, producing a lithium battery outer film:

[0022] The base substrate is laid on the bottom layer, the insulating protective layer is laid on the base substrate, and the puncture-resistant layer is laid on the insulating protective layer, and then co-extrusion flow casting and stretching are performed to form the lithium battery outer film.

[0023] Compared with the prior art, the present application has the following advantages:

[0024] The puncture-resistant lithium battery outer package film and the production process thereof adopt polyurethane fibers and polypropylene fibers to produce longitudinal blocking bodies and transverse blocking bodies, and the longitudinal blocking bodies and the transverse blocking bodies are arranged in the puncture-resistant base body in a longitudinal and transverse interlaced manner, so that the puncture-resistant layer formed by the puncture-resistant base body, the longitudinal blocking body and the transverse blocking body has high strength, resilience and wear resistance, the puncture-resistant performance of the lithium battery outer package film formed by the puncture-resistant layer, the insulation protective layer and the base material bottom layer is improved, the lithium battery is prevented from being damaged, and the service life of the lithium battery is improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] Fig. 1 It is a positive schematic view of the puncture-resistant lithium battery outer package film of the present application.

[0026] Fig. 2 It is an expanded schematic view of the insulation protective layer of the present application.

[0027] Fig. 3 It is a cross-sectional schematic view of the puncture-resistant layer of the present application.

[0028] In the figure: 1, puncture-resistant layer; 11, puncture-resistant base body; 12, longitudinal blocking body; 13, transverse blocking body; 2, insulation protective layer; 21, waterproof layer; 22, heat insulation layer; 23, corrosion prevention layer; 24, insulation layer; 3, base material bottom layer. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0030] In order to solve the problem that the puncture-resistant performance of the existing lithium battery outer package film is poor when in use, the lithium battery is easily damaged, and the service life of the lithium battery is reduced, please refer to Figs. 1-3 The technical solutions provided by the present embodiment are as follows:

[0031] Embodiment one

[0032] A puncture-resistant lithium battery outer package film comprises a puncture-resistant layer 1, an insulation protective layer 2 and a base material bottom layer 3, the puncture-resistant layer 1 is connected on the surface of the insulation protective layer 2 through an adhesive, and the insulation protective layer 2 is connected on the surface of the base material bottom layer 3 through an adhesive, wherein the thickness ratio of the puncture-resistant layer 1, the insulation protective layer 2 and the base material bottom layer 3 is 0.8-1.2:1:0.3.

[0033] Specifically, the lithium battery outer film is formed by the puncture-resistant layer 1, the insulation protective layer 2 and the substrate bottom layer 3, so that the puncture-resistant performance of the lithium battery outer film is improved, the lithium battery is prevented from being damaged, and the service life of the lithium battery is improved.

[0034] It should be noted that the puncture-resistant layer 1 comprises a puncture-resistant substrate 11 made of high-density polyethylene material.

[0035] Specifically, the high-density polyethylene has good heat resistance and cold resistance, good chemical stability, high rigidity and toughness, good mechanical strength, wear resistance, electrical insulation, toughness and cold resistance, and is insoluble in any organic solvent, resistant to acid, alkali and various salt corrosion. Therefore, the puncture-resistant substrate 11 made of high-density polyethylene material has high rigidity and toughness, good mechanical strength, wear resistance, electrical insulation, toughness and cold resistance, and the puncture-resistant performance of the lithium battery outer film is improved.

[0036] It should be noted that the puncture-resistant layer 1 further comprises a longitudinal blocking body 12 and a transverse blocking body 13, the longitudinal blocking body 12 is connected to the transverse blocking body 13, and the longitudinal blocking body 12 and the transverse blocking body 13 are distributed in the puncture-resistant substrate 11 in a longitudinal and transverse staggered manner.

[0037] It should be noted that the puncture-resistant substrate 11 is provided with an assembly groove for the longitudinal blocking body 12 and the transverse blocking body 13, and both ends of the longitudinal blocking body 12 and the transverse blocking body 13 are connected to the groove wall of the assembly groove.

[0038] It should be noted that the longitudinal blocking body 12 and the transverse blocking body 13 each comprise the following raw materials: 20 parts of polyurethane fiber and 16 parts of polypropylene fiber.

[0039] Specifically, polyurethane fiber, also known as spandex, is a synthetic fiber mainly composed of polyurethane, which is divided into two types: polyether type and polyester type. It has excellent elasticity, high strength, and finer linear density, and is more resistant to chemical degradation. Spandex has good acid and alkali resistance, sweat resistance, seawater resistance, dry cleaning resistance, and wear resistance.

[0040] Specifically, polypropylene fiber is a synthetic fiber spun from isotactic polypropylene obtained by polymerization of propylene. It has high strength, good wear resistance and resilience, and electrical insulation.

[0041] Specifically, the polyurethane fiber and the polypropylene fiber are used to produce the longitudinal barrier body 12 and the transverse barrier body 13, and the longitudinal barrier body 12 and the transverse barrier body 13 are arranged in the puncture-resistant base body 11 in a longitudinal and transverse interlaced manner, so that the puncture-resistant layer 1 formed by the puncture-resistant base body 11, the longitudinal barrier body 12 and the transverse barrier body 13 has high strength, resilience and wear resistance, the puncture-resistant performance of the lithium battery outer film is improved, the lithium battery is prevented from being damaged, and the service life of the lithium battery is improved.

[0042] It should be noted that the insulation protective layer 2 includes a waterproof layer 21, a heat insulation layer 22, a corrosion-resistant layer 23 and an insulation layer 24, the waterproof layer 21 is arranged on the heat insulation layer 22, the heat insulation layer 22 is arranged on the corrosion-resistant layer 23, and the corrosion-resistant layer 23 is arranged on the insulation layer 24.

[0043] It should be noted that the base substrate bottom layer 3 is made of polyethylene terephthalate material.

[0044] In order to better show the production process of a puncture-resistant lithium battery outer film, the present embodiment proposes a production process of a puncture-resistant lithium battery outer film according to the above, which includes the following steps:

[0045] S1, producing a puncture-resistant layer 1:

[0046] The polyurethane fiber and the polypropylene fiber are used to process the longitudinal barrier body 12 and the transverse barrier body 13, the high-density polyethylene is used to process the puncture-resistant base body 11, and the processed longitudinal barrier body 12 and transverse barrier body 13 are arranged in the puncture-resistant base body 11 in a longitudinal and transverse interlaced manner to form the puncture-resistant layer 1.

[0047] S2, producing an insulation protective layer 2:

[0048] The waterproof layer 21 is connected to the heat insulation layer 22 by using an adhesive, the heat insulation layer 22 is connected to the corrosion-resistant layer 23, the corrosion-resistant layer 23 is connected to the insulation layer 24, and the insulation protective layer 2 is formed by co-extrusion flow stretching.

[0049] S3, producing a base substrate bottom layer 3:

[0050] The polyethylene terephthalate is used to process the base substrate bottom layer 3 to form the base substrate bottom layer 3.

[0051] S4, producing a lithium battery outer film:

[0052] The base substrate bottom layer 3 is laid on the bottom layer, the insulation protective layer 2 is laid on the base substrate bottom layer 3, and the puncture-resistant layer 1 is laid on the insulation protective layer 2, and the lithium battery outer film is formed by co-extrusion flow stretching.

[0053] Example two

[0054] The puncture-resistant lithium battery outer film comprises a puncture-resistant layer 1, an insulating protective layer 2 and a substrate bottom layer 3, the puncture-resistant layer 1 is connected on the surface of the insulating protective layer 2 through an adhesive, and the insulating protective layer 2 is connected on the surface of the substrate bottom layer 3 through an adhesive, wherein the thickness ratio of the puncture-resistant layer 1, the insulating protective layer 2 and the substrate bottom layer 3 is 0.8-1.2:1:0.3.

[0055] Specifically, the lithium battery outer film is formed by the puncture-resistant layer 1, the insulating protective layer 2 and the substrate bottom layer 3, so that the puncture-resistant performance of the lithium battery outer film is improved, the lithium battery is prevented from being damaged, and the service life of the lithium battery is improved.

[0056] It should be noted that the puncture-resistant layer 1 comprises a puncture-resistant base body 11, and the puncture-resistant base body 11 is made of high-density polyethylene material.

[0057] Specifically, the high-density polyethylene has good heat resistance and cold resistance, good chemical stability, high rigidity and toughness, good mechanical strength, wear resistance, electrical insulation, toughness and cold resistance, is insoluble in any organic solvent, and is resistant to acid, alkali and various salt corrosion, so that the puncture-resistant base body 11 is made of high-density polyethylene material, so that the puncture-resistant base body 11 has high rigidity and toughness, good mechanical strength, wear resistance, electrical insulation, toughness and cold resistance, and the puncture-resistant performance of the lithium battery outer film is improved.

[0058] It should be noted that the puncture-resistant layer 1 further comprises a longitudinal blocking body 12 and a transverse blocking body 13, the longitudinal blocking body 12 is connected to the transverse blocking body 13, and the longitudinal blocking body 12 and the transverse blocking body 13 are distributed in the puncture-resistant base body 11 in a longitudinal and transverse staggered manner.

[0059] It should be noted that the puncture-resistant base body 11 is provided with an assembly groove for accommodating the longitudinal blocking body 12 and the transverse blocking body 13, and both ends of the longitudinal blocking body 12 and the transverse blocking body 13 are connected to the groove wall of the assembly groove.

[0060] It should be noted that the longitudinal blocking body 12 and the transverse blocking body 13 each comprise the following raw materials: 20 parts of polyurethane fiber and 32 parts of polypropylene fiber.

[0061] Specifically, the polyurethane fiber, also known as spandex, is a synthetic fiber mainly composed of polyurethane, which is divided into two types of polyether and polyester, has excellent elasticity, high strength, finer linear density, and is more resistant to chemical degradation, and has good acid and alkali resistance, sweat resistance, seawater resistance, dry cleaning resistance and wear resistance.

[0062] Specifically, the polypropylene fiber is a synthetic fiber spun from isotactic polypropylene obtained by polymerization of propylene, which has high strength, good wear resistance and resilience, and electrical insulation.

[0063] Specifically, the polyurethane fiber and the polypropylene fiber are used to produce the longitudinal barrier 12 and the transverse barrier 13, and the longitudinal barrier 12 and the transverse barrier 13 are arranged in the puncture-resistant base body 11 in a longitudinal and transverse staggered manner, so that the puncture-resistant layer 1 formed by the puncture-resistant base body 11, the longitudinal barrier 12 and the transverse barrier 13 has high strength, resilience and wear resistance, the puncture-resistant performance of the lithium battery outer film is improved, the lithium battery is prevented from being damaged, and the service life of the lithium battery is improved.

[0064] It should be noted that the insulation protective layer 2 includes a waterproof layer 21, a heat insulation layer 22, a corrosion-resistant layer 23 and an insulation layer 24, the waterproof layer 21 is arranged on the heat insulation layer 22, the heat insulation layer 22 is arranged on the corrosion-resistant layer 23, and the corrosion-resistant layer 23 is arranged on the insulation layer 24.

[0065] It should be noted that the base substrate bottom layer 3 is made of polyethylene terephthalate material.

[0066] The lithium battery outer film is produced by using the same production process as in Example 1, and the difference between Example 1 and Example 2 is that the mass fraction of the polypropylene fiber is increased in Example 2.

[0067] Example Three

[0068] A puncture-resistant lithium battery outer film includes a puncture-resistant layer 1, an insulation protective layer 2 and a base substrate bottom layer 3, the puncture-resistant layer 1 is connected to the surface of the insulation protective layer 2 by an adhesive, and the insulation protective layer 2 is connected to the surface of the base substrate bottom layer 3 by an adhesive, wherein the thickness ratio of the puncture-resistant layer 1, the insulation protective layer 2 and the base substrate bottom layer 3 is 0.8-1.2:1:0.3.

[0069] Specifically, the lithium battery outer film is formed by the puncture-resistant layer 1, the insulation protective layer 2 and the base substrate bottom layer 3, the puncture-resistant performance of the lithium battery outer film is improved, the lithium battery is prevented from being damaged, and the service life of the lithium battery is improved.

[0070] It should be noted that the puncture-resistant layer 1 includes a puncture-resistant base body 11, and the puncture-resistant base body 11 is made of high-density polyethylene material.

[0071] Specifically, the high-density polyethylene has good heat resistance and cold resistance, good chemical stability, high rigidity and toughness, good mechanical strength, wear resistance, electrical insulation, toughness and cold resistance, and is insoluble in any organic solvent, resistant to acid, alkali and various salt corrosion, so that the puncture-resistant base body 11 made of high-density polyethylene material has high rigidity and toughness, good mechanical strength, good wear resistance, electrical insulation, toughness and cold resistance, and the puncture-resistant performance of the lithium battery outer film is improved.

[0072] It should be noted that the puncture-resistant layer 1 also includes longitudinal blocking bodies 12 and transverse blocking bodies 13, the longitudinal blocking bodies 12 are connected to the transverse blocking bodies 13, and the longitudinal blocking bodies 12 and the transverse blocking bodies 13 are arranged in a longitudinal and transverse staggered manner in the puncture-resistant base body 11.

[0073] It should be noted that the puncture-resistant base body 11 is provided with assembly grooves for accommodating the longitudinal blocking bodies 12 and the transverse blocking bodies 13, and both ends of the longitudinal blocking bodies 12 and the transverse blocking bodies 13 are connected to the groove walls of the assembly grooves.

[0074] It should be noted that the longitudinal blocking bodies 12 and the transverse blocking bodies 13 each include the following raw materials: 36 parts of polyurethane fiber and 16 parts of polypropylene fiber.

[0075] Specifically, polyurethane fiber, also known as spandex, is a synthetic fiber with polyurethane as the main component, which is divided into two types: polyether type and polyester type. It has excellent elasticity, high strength, and finer linear density, and is more resistant to chemical degradation. Spandex has good acid and alkali resistance, sweat resistance, seawater resistance, dry cleaning resistance, and wear resistance.

[0076] Specifically, polypropylene fiber is a synthetic fiber made of isotactic polypropylene obtained by polymerization of propylene. It has high strength, good wear resistance and resilience, and electrical insulation.

[0077] Specifically, polyurethane fiber and polypropylene fiber are used to produce longitudinal blocking bodies 12 and transverse blocking bodies 13, and the longitudinal blocking bodies 12 and the transverse blocking bodies 13 are arranged in a longitudinal and transverse staggered manner in the puncture-resistant base body 11. The puncture-resistant layer 1 formed by the puncture-resistant base body 11, the longitudinal blocking bodies 12 and the transverse blocking bodies 13 has high strength, resilience and wear resistance, which can improve the puncture resistance of the lithium battery outer film, prevent the lithium battery from being damaged, and prolong the service life of the lithium battery.

[0078] It should be noted that the insulating protective layer 2 includes a waterproof layer 21, a heat insulation layer 22, a corrosion-resistant layer 23 and an insulating layer 24, the waterproof layer 21 is arranged on the heat insulation layer 22, the heat insulation layer 22 is arranged on the corrosion-resistant layer 23, and the corrosion-resistant layer 23 is arranged on the insulating layer 24.

[0079] It should be noted that the base material bottom layer 3 is made of polyethylene terephthalate material.

[0080] The same production process as in Example 1 is used to produce a lithium battery outer film, and the difference from Example 1 is that the mass fraction of polyurethane fiber is increased in Example 3.

[0081] Comparative Example 1

[0082] A puncture-resistant lithium battery outer film, comprising a puncture-resistant layer 1, an insulating protective layer 2 and a substrate bottom layer 3, the puncture-resistant layer 1 is connected on the surface of the insulating protective layer 2 by an adhesive, and the insulating protective layer 2 is connected on the surface of the substrate bottom layer 3 by an adhesive, wherein the thickness ratio of the puncture-resistant layer 1, the insulating protective layer 2 and the substrate bottom layer 3 is 0.8-1.2:1:0.3.

[0083] It should be noted that the puncture-resistant layer 1 comprises a puncture-resistant base body 11, and the puncture-resistant base body 11 is made of high-density polyethylene material.

[0084] It should be noted that the insulating protective layer 2 comprises a waterproof layer 21, a heat insulation layer 22, a corrosion-resistant layer 23 and an insulating layer 24, the waterproof layer 21 is arranged on the heat insulation layer 22, the heat insulation layer 22 is arranged on the corrosion-resistant layer 23, and the corrosion-resistant layer 23 is arranged on the insulating layer 24.

[0085] It should be noted that the substrate bottom layer 3 is made of polyethylene terephthalate material.

[0086] Compared with Example 1, the longitudinal blocking body 12 and the transverse blocking body 13 structure are cancelled in Comparative Example 1, and the same production process as Example 1 is adopted to produce the lithium battery outer film, and the production steps of the longitudinal blocking body 12 and the transverse blocking body 13 are cancelled accordingly.

[0087] Comparative Example 2

[0088] A puncture-resistant lithium battery outer film, comprising an insulating protective layer 2 and a substrate bottom layer 3, the insulating protective layer 2 is connected on the surface of the substrate bottom layer 3 by an adhesive, wherein the thickness ratio of the insulating protective layer 2 and the substrate bottom layer 3 is 1:0.3.

[0089] It should be noted that the insulating protective layer 2 comprises a waterproof layer 21, a heat insulation layer 22, a corrosion-resistant layer 23 and an insulating layer 24, the waterproof layer 21 is arranged on the heat insulation layer 22, the heat insulation layer 22 is arranged on the corrosion-resistant layer 23, and the corrosion-resistant layer 23 is arranged on the insulating layer 24.

[0090] It should be noted that the substrate bottom layer 3 is made of polyethylene terephthalate material.

[0091] Compared with Example 1, the puncture-resistant layer 1 structure is cancelled in Comparative Example 2, and the same production process as Example 1 is adopted to produce the lithium battery outer film, and the production steps of the puncture-resistant layer 1 are cancelled accordingly.

[0092] The lithium battery outer films produced in Examples 1-3 and Comparative Examples 1-2 are tested for performance, and the performance test results of the lithium battery outer films are shown in Table 1:

[0093] Table 1: Performance test results of lithium battery outer film

[0094]

[0095]

[0096] From the above table, it can be seen that the outer package films of lithium batteries produced in Examples 1 to 3 all have good puncture resistance.

[0097] Among them, compared with Example 1, the puncture resistance of Example 2 is improved, which shows that increasing the mass fraction of polypropylene fibers can improve the puncture resistance of the outer package film of the lithium battery;

[0098] Among them, compared with Example 1, the puncture resistance of Example 3 is improved, which shows that increasing the mass fraction of polyurethane fibers can improve the puncture resistance of the outer package film of the lithium battery;

[0099] Among them, compared with Example 1, the puncture resistance of Comparative Example 1 is reduced, because the longitudinal blocking body 12 and the transverse blocking body 13 are not increased in Comparative Example 1, which leads to the reduction of the puncture resistance of the outer package film of the lithium battery, which shows that the longitudinal blocking body 12 and the transverse blocking body 13 can improve the puncture resistance of the outer package film of the lithium battery;

[0100] Among them, compared with Example 1, the puncture resistance of Comparative Example 2 is reduced, because the puncture-resistant layer 1 is not increased in Comparative Example 2, which leads to the reduction of the puncture resistance of the outer package film of the lithium battery, which shows that the puncture-resistant layer 1 can improve the puncture resistance of the outer package film of the lithium battery.

[0101] Therefore, using polyurethane fibers and polypropylene fibers to produce the longitudinal blocking body 12 and the transverse blocking body 13, and longitudinally and transversely interlacing the longitudinal blocking body 12 and the transverse blocking body 13 in the puncture-resistant base body 11 can make the puncture-resistant layer 1 formed by the puncture-resistant base body 11, the longitudinal blocking body 12 and the transverse blocking body 13 have higher strength, resilience and wear resistance, and the outer package film of the lithium battery produced can have better puncture resistance.

[0102] In summary, the puncture-resistant outer package film of the lithium battery and the production process thereof of the present application use polyurethane fibers and polypropylene fibers to produce the longitudinal blocking body 12 and the transverse blocking body 13, and longitudinally and transversely interlacing the longitudinal blocking body 12 and the transverse blocking body 13 in the puncture-resistant base body 11, which can make the puncture-resistant layer 1 formed by the puncture-resistant base body 11, the longitudinal blocking body 12 and the transverse blocking body 13 have higher strength, resilience and wear resistance, and can improve the puncture resistance of the outer package film of the lithium battery formed by the puncture-resistant layer 1, the insulating protective layer 2 and the substrate bottom layer 3, prevent the damage of the lithium battery, and improve the service life of the lithium battery.

[0103] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting; it is not intended to exclude myriad other embodiments of the present application that other inventors can develop based on the same general inventive concepts embodied by the described embodiments. That is, although the present application is described in terms of particular embodiments and illustrative figures, it should be apparent that the scope of the present application is not limited to these specific embodiments.

[0104] While the embodiments of the application have been shown and described herein, it will be understood by those of ordinary skill in the art that various changes, modifications, alternatives, and variations can be made to the embodiments without departing from the spirit and scope of the application, which is defined by the claims and their equivalents.

Claims

1. A process for producing a puncture-resistant lithium battery outer envelope for producing a puncture-resistant lithium battery outer envelope comprising a puncture-resistant layer (1), an insulating protective layer (2) and a substrate base layer (3), characterized in that, The puncture-resistant layer (1) is connected to the surface of the insulation protective layer (2) by adhesive, the insulation protective layer (2) is connected to the surface of the substrate bottom layer (3) by adhesive, wherein the thickness ratio of the puncture-resistant layer (1), the insulation protective layer (2) and the substrate bottom layer (3) is 0.8-1.2:1:0.3; The puncture-resistant layer (1) comprises a puncture-resistant base body (11) made of high-density polyethylene, and longitudinal blocking bodies (12) and transverse blocking bodies (13), the longitudinal blocking bodies (12) are connected to the transverse blocking bodies (13), and the longitudinal blocking bodies (12) and the transverse blocking bodies (13) are distributed in the puncture-resistant base body (11) in a longitudinal and transverse staggered manner. The production process of the puncture-resistant lithium battery outer film comprises the following steps: S1, producing the puncture-resistant layer (1): Polyurethane fibers and polypropylene fibers are used to process the longitudinal blocking bodies (12) and the transverse blocking bodies (13), high-density polyethylene is used to process the puncture-resistant base body (11), and the longitudinal blocking bodies (12) and the transverse blocking bodies (13) are assembled in the puncture-resistant base body (11) in a longitudinal and transverse staggered manner to form the puncture-resistant layer (1); S2, producing the insulation protective layer (2): An adhesive is used to connect the waterproof layer (21) to the heat insulation layer (22), connect the heat insulation layer (22) to the corrosion-resistant layer (23), and connect the corrosion-resistant layer (23) to the insulation layer (24), and then co-extrusion flow stretching is performed to form the insulation protective layer (2); S3, producing the substrate bottom layer (3): Polyethylene terephthalate is used to process the substrate bottom layer (3) to form the substrate bottom layer (3); S4, producing the lithium battery outer film: The substrate bottom layer (3) is laid on the bottom layer, the insulation protective layer (2) is laid on the substrate bottom layer (3), and the puncture-resistant layer (1) is laid on the insulation protective layer (2), and then co-extrusion flow stretching is performed to form the lithium battery outer film.

2. The process for producing a puncture-resistant outer envelope for lithium batteries according to claim 1, characterized in that, The puncture-resistant base body (11) is provided with assembly grooves for accommodating the longitudinal blocking bodies (12) and the transverse blocking bodies (13), and the two ends of the longitudinal blocking bodies (12) and the transverse blocking bodies (13) are connected to the groove walls of the assembly grooves.

3. The process for producing a puncture-resistant outer envelope for lithium batteries according to claim 2, characterized in that, The longitudinal blocking bodies (12) and the transverse blocking bodies (13) each comprise the following raw materials in mass fraction: 20-36 parts of polyurethane fibers and 16-32 parts of polypropylene fibers.

4. The process for producing a puncture-resistant outer envelope for lithium batteries according to claim 3, characterized in that, The insulation protective layer (2) comprises a waterproof layer (21), a heat insulation layer (22), a corrosion-resistant layer (23) and an insulation layer (24), the waterproof layer (21) is arranged on the heat insulation layer (22), the heat insulation layer (22) is arranged on the corrosion-resistant layer (23), and the corrosion-resistant layer (23) is arranged on the insulation layer (24).

5. The process for producing a puncture-resistant outer envelope for lithium batteries according to claim 4, characterized in that, The substrate bottom layer (3) is made of polyethylene terephthalate.

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