PFPI film for energy battery

Abstract

The utility model discloses a PFPI membrane for an energy battery, which comprises a battery shell, a plurality of positive pole layers and negative pole layers are coaxially arranged in the battery shell, the positive pole layers and the negative pole layers are staggered and crossed, the PFPI membrane is arranged between the positive pole layers and the negative pole layers, and the PFPI membrane is processed by taking a PI membrane as a base material. According to the utility model, the PFPI film is adopted to replace a PP (Polypropylene), PE (Polyethylene) or PET (Polyethylene Terephthalate) film in a traditional battery, and the excellent performance of the PFPI film is utilized, so that the defects of explosion, fire, detonation and the like caused by high-energy charging and discharging of the traditional battery are avoided, and the safety performance of the lithium ion battery and a super capacitor (also called as an electrochemical capacitor) is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of energy battery, specifically a PFPI film for energy battery. BACKGROUND

[0002] The battery diaphragm is indispensable in the energy battery technology, and the diaphragm in the solid-state battery plays a crucial role in ensuring the safety and stability of the battery. Its unique structure and material properties also make the solid-state battery have significant advantages in energy density and charging speed. The battery diaphragm has the following main functions: 1. current limiting effect, the diaphragm as an internal barrier of the battery can limit the current flow between the positive and negative electrodes, thereby maintaining the safety and stability of the battery; 2. ion blocking effect, the diaphragm can prevent the penetration of positive and negative ions, ensuring that the electrochemical reaction of the battery only occurs in the electrolyte; 3. prevent battery short circuit, the diaphragm can prevent the mixing of substances between the electrodes, thereby effectively preventing the short circuit phenomenon of the battery. The solid-state battery diaphragm has high thermal stability and chemical stability, which can effectively avoid overheating, explosion and other safety hazards. The solid-state battery diaphragm can make full use of the internal space of the battery, improve the energy density and endurance, and has excellent ion conductivity, so that the battery can realize fast charging.

[0003] At present, the diaphragm used in domestic solid-state batteries is mostly PP, PE or PET diaphragm. This kind of film cannot withstand full power carrying, and high energy charging and discharging can easily cause explosion, fire, deflagration and other disadvantages. (PP, PE or PET film can withstand 110℃ working temperature rise, which is much lower than the full power charging and discharging temperature. The internal temperature of the super capacitor rises to 170℃ during full power charging and discharging, so the film deforms and melts, causing positive and negative short circuit, which is the real reason for the explosion, fire and deflagration of lithium batteries.) Therefore, a new film structure is needed to replace the traditional PP, PE or PET film. UTILITY MODEL CONTENTS

[0004] In view of the shortcomings of the prior art, the utility model provides a PFPI film for energy battery to solve the problems that the PP, PE or PET diaphragm in the existing battery cannot withstand full power carrying, and high energy charging and discharging can easily cause explosion, fire, deflagration and other disadvantages.

[0005] To achieve the above purpose, the utility model realizes the following technical scheme: a PFPI film for energy battery, comprising a battery shell, a plurality of positive electrode layers and negative electrode layers are coaxially arranged in the inside of the battery shell, the positive electrode layers and the negative electrode layers are staggered and crossed, a PFPI film is arranged between the positive electrode layers and the negative electrode layers, and the PFPI film is processed from a PI film as a base material.

[0006] Preferably, the PI film is a polyimide substrate. The polyimide substrate is a polymer containing imide rings in the main chain, which is one of the best materials in organic polymer materials in terms of comprehensive performance, has excellent high-temperature resistance, can withstand high temperatures above 400 DEG C, and can be used for a long time in the temperature range of -200 DEG C to 300 DEG C, and some polyimides even have no obvious melting point. In addition, the polyimide also has high insulation performance, the dielectric constant is 4.0 at 103 Hz, and the dielectric loss is only 0.004-0.007, which is F to H grade insulation material, so that the melting point of the PFPI film can be greatly improved, and the safety performance of the battery can be improved.

[0007] Preferably, the thickness of the PFPI film is between 16 μm and 35 μm, the thickness of the diaphragm is related to the internal resistance, the thinner the diaphragm, the smaller the internal resistance, and the better the high-power charge and discharge performance. The thickness of the lithium ion battery is generally 25 μm, so the thickness of the PFPI film can reach 16 μm, and the discharge performance of the PFPI film can be effectively improved.

[0008] Preferably, the PFPI film is provided with a microporous structure, and the microporous structure is between 0.1 μm and 30 μm. The microporous structure is uniformly distributed in the entire diaphragm, and the currently used electrode particles are generally below 35 microns, the pore size is 0.1-30 microns according to the current standard in the United States, and the pore size is too small to increase the resistance, and the pore size is too large to form dendritic crystal puncture short circuit.

[0009] Preferably, the porosity of the microporous structure on the PFPI film is between 25% and 65%. The porosity is the volume percentage of the volume of the holes in the monomer film, which is related to the density of the material resin and the film. The fineness and internal resistance of the porosity have certain relationship, the porosity of the PFPI diaphragm is between 25%-65 %, so that the resistivity can be effectively reduced, and the discharge power of the battery can be improved.

[0010] Preferably, the MacMullin value of the PFPI film is less than 5. The MacMullin value is the ratio between the resistivity of the diaphragm containing electrolyte and the resistivity of the electrolyte itself, the smaller the value, the better, the value of the traditional consumable lithium ion battery is about 8, and the value of the PFPI film is less than 5.

[0011] The utility model provides a PFPI film for energy battery possesses the following beneficial effects:

[0012] The utility model discloses a PFPI film is used to replace PP, PE or PET film in traditional battery, utilizes the superior performance of PFPI film, avoids the explosion, fire, deflagration and other drawbacks caused by high energy charge and discharge of traditional battery, improves the safety performance of lithium ion battery and super capacitor (also called electrochemical capacitor). ACCURACY OF DRAWINGS

[0013] Figure 1 The application diagram of the PFPI film in the battery.

[0014] In the figure:

[0015] 1, positive electrode layer; 2, PFPI film; 3, negative electrode layer. DETAILED DESCRIPTION

[0016] 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 of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0017] Please refer to Figure 1 The present application provides a technical solution: a PFPI film for an energy battery, comprising a battery shell, a plurality of layers of positive electrode layers 1 and negative electrode layers 3 are coaxially arranged inside the battery shell, the positive electrode layers 1 and the negative electrode layers 3 are staggered and crossed, a PFPI film 2 is arranged between the positive electrode layers 1 and the negative electrode layers 3, and the PFPI film 2 is processed from a PI film as a base material.

[0018] In the present embodiment, the PI film is a polyimide base material. The polyimide base material main chain contains an imide ring polymer, which is one of the best comprehensive performance materials in organic polymer materials, has excellent high temperature resistance, can withstand high temperatures above 400°C, and can be used for a long time in the temperature range of -200 to 300°C, and some polyimides even have no obvious melting point. In addition, polyimide also has high insulation performance, with a dielectric constant of 4.0 at 103 Hz and a dielectric loss of only 0.004-0.007, being F to H grade insulating material, so as to greatly improve the melting point of the PFPI film 2 and improve the safety performance of the battery.

[0019] In the present embodiment, the thickness of the PFPI film 2 is between 16 μm and 35 μm, and the thickness of the diaphragm is related to the internal resistance. The thinner the diaphragm, the smaller the internal resistance, and the better the high-power charge and discharge performance. The thickness of the current lithium ion battery is generally 25 μm, so the thickness of the PFPI film 2 can reach 16 μm, effectively improving the discharge performance of the PFPI film 2.

[0020] In the present embodiment, the PFPI film 2 is provided with a microporous structure, and the microporous structure is between 0.1 μm and 30 μm. The microporous structure is uniformly distributed in the entire diaphragm. The currently used electrode particles are generally below 35 microns, the pore size is 0.1-30 microns according to the current standard in the United States, and the pore size is too small to increase the resistance, and the pore size is too large to form dendritic crystal puncture short circuit.

[0021] In the embodiment, the porosity of the microporous structure on the PFPI film 2 is between 25% and 65%. The porosity is the percentage of the volume of the pores in the volume of the monomer film, which is related to the density of the material resin and the film. The porosity is related to the internal resistance, and the porosity of the PFPI diaphragm is between 25% and 65%, so that the resistivity can be effectively reduced, and the discharge power of the battery can be improved.

[0022] In the embodiment, the MacMullin value of the PFPI film 2 is less than 5. The MacMullin value is the ratio between the resistivity of the diaphragm containing electrolyte and the resistivity of the electrolyte itself, and the smaller the value is, the better. The MacMullin value of the conventional consumable lithium ion battery is about 8, and the MacMullin value of the PFPI film 2 is less than 5.

[0023] The utility model discloses a PFPI film 2 instead of PP, PE or PET film in the conventional battery, using the superior performance of PFPI film 2, avoiding the explosion, fire, deflagration and other drawbacks caused by the high energy charge and discharge of the conventional battery, improving the safety performance of lithium ion battery and super capacitor (also known as electrochemical capacitor).

[0024] Although the embodiments of the utility model have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the utility model, and the scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A PFPI film for a power battery, comprising a battery casing, wherein a plurality of positive electrode layers (1) and negative electrode layers (3) are coaxially disposed inside the battery casing, the positive electrode layers (1) and the negative electrode layers (3) being staggered and intersecting, characterized in that: A PFPI film (2) is disposed between the positive electrode layer (1) and the negative electrode layer (3), and the PFPI film (2) is processed from a PI film as a substrate.

2. The PFPI film for energy batteries according to claim 1, characterized in that: The PI film is a polyimide substrate.

3. The PFPI film for energy batteries according to claim 1, characterized in that: The thickness of the PFPI film (2) is between 16 μm and 35 μm.

4. The PFPI film for energy batteries according to claim 1, characterized in that: The PFPI membrane (2) has a microporous structure, and the microporous structure is between 0.1 μm and 30 μm.

5. A PFPI film for energy batteries according to claim 4, characterized in that: The porosity of the microporous structure on the PFPI membrane (2) is between 25% and 65%.

6. The PFPI film for energy batteries according to claim 1, characterized in that: The MacMμllin value of the PFPI film (2) is less than 5.

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