Dielectric thin film for solid-state and solid-state-like lithium batteries

Abstract

The invention discloses a dielectric film for solid-state and solid-state-like lithium batteries, the dielectric film comprises a first film layer, a second film layer and a third film layer, the first film layer is connected with a positive electrode, the third film layer is connected with a negative electrode, and the second film layer is located between the first film layer and the third film layer; the first thin film layer comprises a first high polymer material; part of the first high polymer material also has the effect of a plasticizer; the first lithium salt is dispersed in the first high polymer material; the second thin film layer comprises a second polymer material; part of the second polymer material also has the effect of a plasticizer; the second lithium salt is dispersed in the second polymer material; the second inorganic ceramic is dispersed in the second high polymer material; the third thin film layer comprises a third high polymer material, and part of the third high polymer material also has the effect of a plasticizer; the third lithium salt is dispersed in the third high polymer material; and the third inorganic ceramic is dispersed in the third polymer material.

Description

Technical Field

[0001] The present invention relates to the technical field of dielectric films for batteries, and in particular to a dielectric film for solid-state and quasi-solid-state lithium batteries. Background Art

[0002] The solid-state or quasi-solid-state battery structure in the prior art is composed of a negative electrode, a positive electrode, and a dielectric film structure located between the positive electrode and the negative electrode. The negative electrode is filled with a negative electrode slurry as a binder. The negative electrode also contains a plurality of negative electrode particles distributed in the negative electrode slurry. The positive electrode is filled with a positive electrode slurry as a binder. The positive electrode also contains a plurality of positive electrode particles distributed in the positive electrode slurry. In addition, the dielectric film of the solid-state battery is located between the negative electrode and the positive electrode to isolate and connect the negative electrode and the positive electrode.

[0003] In traditional solid or quasi-solid electrolytes, the positive and negative electrode slurries are used to guide lithium ions. However, the positive and negative electrode slurries in conventional technology are prone to side reactions with the lithium ions remaining in the positive and negative electrode slurries, which can easily cause dead lithium or lithium consumption. This is an irreversible chemical reaction, which causes the number of lithium ions in the battery to decrease, and the battery's storage capacity is also reduced. In addition, the lithium capacity of the multiple positive and negative electrode particles in the positive and negative electrode slurries is poor, so the lithium ions in the positive and negative electrode slurries are easily gathered on the surface of the positive and negative electrode particles. At this time, these lithium ions will produce side reactions with the molecules in the positive and negative electrode slurries, which will reduce the capacity of the entire positive and negative electrodes under long-term use. In addition, the number of lithium ions is reduced due to side reactions. Therefore, the battery's storage capacity is reduced.

[0004] Conventional single-layer dielectric films have a relatively rigid structure and a low lithium salt concentration. Therefore, when the single-layer dielectric film is bonded to the positive electrode, the stacking between them is not tight, resulting in poor structure and bonding. In addition, traditional dielectric film materials cannot fill the cracks between the two, which easily leads to short circuits and reduced yield.

[0005] Furthermore, conventional single-layer dielectric films contain only a single lithium salt concentration, requiring a higher energy level for lithium ions to conduct, resulting in poor ionic conductivity and, consequently, lower overall battery performance. The poor ionic conductivity of the single-layer dielectric film when bonded to the negative electrode makes it susceptible to the deposition of dead lithium at the negative electrode, increasing the risk of lithium crystal formation and puncture, thereby reducing the battery's storage capacity.

[0006] Therefore, the present invention hopes to provide a new dielectric film for solid-state and quasi-solid-state lithium batteries to solve the above-mentioned defects in the prior art.

[0007] Therefore, the existing technology has defects and needs to be improved. Summary of the Invention

[0008] Therefore, the purpose of this technical solution is to solve the above-mentioned problems in the conventional technology. This technical solution proposes a dielectric film for solid-state and quasi-solid-state lithium batteries. In order to use the design of this case, the first film layer and the third film layer of this case are added on both sides of the traditional single-layer dielectric film. The first film layer and the third film layer have a relatively soft structure, so they can fill the gap between the positive and negative electrodes, and can also increase battery performance, reduce the risk of short circuits, improve battery yield, and improve the gap when the positive and negative electrodes are bonded.

[0009] To achieve the above-mentioned purpose, the present technical solution proposes a dielectric film for solid-state and quasi-solid-state lithium batteries, wherein the solid-state or quasi-solid-state battery structure is composed of a negative electrode, a positive electrode and a dielectric film structure located between the positive electrode and the negative electrode; wherein the negative electrode is filled with a negative electrode slurry as a binder; the negative electrode also contains a plurality of negative electrode particles; the positive electrode is filled with a positive electrode slurry as a binder; the positive electrode also contains a plurality of positive electrode particles; the dielectric film is located between the negative electrode and the positive electrode, and the dielectric film includes a first film layer, a second film layer and a third film layer, wherein the first film layer is connected to the positive electrode, the third film layer is connected to the negative electrode, and the second film layer is connected between the first film layer and the third film layer; wherein the first film layer includes: a first polymer material As the substrate of the first film layer; wherein the first polymer material is a mixture of PVDF-HFP (polyvinylidene fluoride-hexafluoropropylene), ADN (adiponitrile), GLN (glutaronitrile) and SN (succinonitrile); ADN, GLN and SN in the first polymer material have the function of plasticizers, which are dispersed in PVDF-HFP and have the function of dispersing the structure of the entire first polymer material to reduce the precipitation of crystals of the first polymer material and help the dissociation of lithium salts, thereby making the entire first film layer easy to conduct lithium ions and easy to shape; the first lithium salt is dispersed in the first polymer material, wherein the first lithium salt is LiBOB (lithium bis(oxalatoborate)) and LiTFSI (lithium bis(trifluoromethylsulfonyl)amide) and Li FSI (lithium bis(fluorosulfonyl imide)); wherein the second film layer comprises: a second polymer material as the substrate of the second film layer, wherein the second polymer material comprises: a mixture of PVDF-HFP, PAN (polyacrylonitrile) and SN; wherein the PAN and SN in the second polymer material have the function of plasticizers and are dispersed in PVDF-HFP; in addition, PAN and SN with plasticizer function can help the lithium salt in the second film layer to dissociate and improve the ionic conductivity of the membrane; the second lithium salt is dispersed in the second polymer material, and the second lithium salt comprises LiFSI and LiTSFI; the second inorganic ceramic is dispersed in the second polymer material, and the second inorganic ceramic is a plurality of first LLZO coated with a dopamine layer on the outside Particles; wherein the third film layer comprises: a third polymer material as a substrate of the third film layer; wherein the third polymer material comprises: a mixture of PEO (polyethylene oxide) and PAN, PEO has high stability and appropriate ionic conductivity at the negative electrode reduction potential; PAN has good electronic and ionic conductivity, so the overall performance of PEO can be further improved under the mixing of PAN; wherein the PAN in the third polymer material acts as a plasticizer and is dispersed in the PEO; a third lithium salt is dispersed in the third polymer material; wherein the third lithium salt is LiTFSI; and a third inorganic ceramic is dispersed in the third polymer material, wherein the third inorganic ceramic is a plurality of second LLZO particles coated with a dopamine layer on the outside;The third inorganic ceramic is used to enhance ionic conductivity.

[0010] The following description will provide a further understanding of the features and advantages of this technical solution. Please refer to the accompanying drawings when reading. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A schematic diagram showing this embodiment is shown.

[0012] Figure 2 Shows the structural diagram of this case.

[0013] Figure 3 A structural diagram showing a first LLZO particle coated with a dopamine layer in this embodiment.

[0014] Figure 4 A diagram showing the structure of a second LLZO particle coated with a dopamine layer in this embodiment. DETAILED DESCRIPTION

[0015] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] The structural composition of the present invention, as well as the effects and advantages it can produce, are described in detail below with reference to the accompanying drawings and a preferred embodiment of the present invention.

[0017] Please refer to Figures 1 to 4 As shown, the dielectric film for solid-state and quasi-solid-state lithium batteries of the present technical solution includes the following elements:

[0018] The solid-state or quasi-solid-state battery structure in the conventional technology is composed of a negative electrode 10, a positive electrode 20 and a dielectric film 30 located between the positive electrode 20 and the negative electrode 10. Figure 2 As shown. The negative electrode 10 is filled with a negative electrode slurry 12 serving as a binder. The negative electrode 10 also includes a plurality of negative electrode particles 15 (e.g., SiC particles with a tin layer) distributed within the negative electrode slurry 12. The outer surfaces of the negative electrode particles 15 accommodate lithium ions and function to evenly distribute the lithium ions throughout the negative electrode. However, the negative electrode particles 15 can react with some of the lithium ions, reducing the number of available lithium ions and, over time, reducing the overall battery's capacitance.

[0019] In addition, the positive electrode 20 is filled with a positive electrode slurry 22 as a binder. The positive electrode 20 also includes a plurality of positive electrode particles 26, which are distributed in the positive electrode slurry 22. The chemical molecules that constitute the positive electrode slurry 22 and the positive electrode particles 26 will produce side reactions with the lithium ions passing through, thereby consuming the lithium ions that can be used. In addition, the dielectric film 30 of the solid-state battery is located between the negative electrode 10 and the positive electrode 20, serving to separate and connect the negative electrode 10 and the positive electrode 20.

[0020] The dielectric film 30 is located between the negative electrode 10 and the positive electrode 20. The dielectric film 30 includes a first film layer 31, a second film layer 32, and a third film layer 33. The first film layer 31 is connected to the positive electrode 20, the third film layer 33 is connected to the negative electrode 10, and the second film layer 32 is connected between the first film layer 31 and the third film layer 33 (as shown in FIG. Figure 1 and Figure 2 ).

[0021] The first film layer 31 comprises:

[0022] The first polymer material 311 serves as the substrate of the first film layer 31 . In this embodiment, the first polymer material includes:

[0023] A mixture of PVDF-HFP (polyvinylidene fluoride-hexafluoropropylene), ADN (adiponitrile), GLN (glutaronitrile), and SN (succinonitrile) is used as a base material. This first polymer material 311 forms the substrate of the first film layer 31 of the dielectric film 30. In the first polymer material 311, the ratio of the weight of PVDF-HFP to the total weight of ADN, GLN, and SN is 12:1 to 8:1.

[0024] The ADN, GLN, and SN in the first polymer material 311 act as plasticizers. Dispersed within the PVDF-HFP, they disperse the structure of the entire first polymer material 311, reducing crystallization and aiding lithium salt dissociation. This allows the entire first film layer 311 to easily conduct lithium ions and facilitate shaping. The weight ratio of ADN, GLN, and SN ranges from 1:2:7 to 0.5:1:9.5.

[0025] A first lithium salt 312 is dispersed in the first polymer material 311. The first lithium salt 312 comprises a mixture of LiBOB (lithium bis(oxalatoborate), LiTFSI (lithium bis(trifluoromethylsulfonyl)amide), and LiFSI (lithium bis(trifluoromethylsulfonyl)imide). The weight ratio of the first lithium salt 312 to the first polymer material 311 is between 1:2.5 and 1:5. The LiTFSI and LiFSI enhance lithium ion conductivity, while the LiBOB protects the LiTFSI and LiFSI from water corrosion and from attack by HF (hydrofluoric acid) generated by the reaction between water and LiTFSI, which could degrade overall battery performance. Furthermore, the first lithium salt 312 can withstand a higher voltage differential, thereby making the first polymer material 311 relatively stable under the high voltage of the positive electrode 20. The addition of the LiBOB enhances overall stability. In the first thin film layer 31 , the weight ratio of the total weight of the LiTFSI and the LiFSI to the weight of the LiBOB is 2:3 (weight ratio). The weight ratio of the LiFSI to the LiTFSI is 2:1.

[0026] The second film layer 32 comprises:

[0027] The second polymer material 321 serves as the substrate of the second film layer 32. In this case, the second polymer material 321 includes: PVDF-HFP, PAN (polyacrylonitrile) and SN as a base material, wherein in the second polymer material 321, the weight ratio of the PVDF-HFP weight to the PAN weight to the SN weight is between 8:1.2:1 and 8:1:1.6. These second polymer materials 321 form the substrate of the second film layer 32 of the dielectric film 30.

[0028] The PAN and SN in the second polymer material 321 act as plasticizers. Dispersed within the PVDF-HFP, they disperse the entire structure of the second polymer material 321 to reduce crystalline precipitation. Furthermore, the plasticizers PAN and SN help dissociate the lithium salt in the second film layer 32, improving the membrane's ionic conductivity.

[0029] A second lithium salt 322 is dispersed within the second polymer material 321. The second lithium salt 322 comprises LiFSI and LiTSFI. In the second thin film layer 32, the weight ratio of LiFSI to LiTSFI is 1:2. The addition of the second lithium salt 322 is intended to lower the energy level of lithium ions during conduction within the polymer materials, while enhancing stability and increasing conductivity. The weight ratio of the total weight of the second lithium salt 322 to the total weight of the second polymer material 321 is between 1:3 and 1:9.

[0030] The second inorganic ceramic 323 is dispersed in the second polymer material 321. The second inorganic ceramic 323 is a plurality of first LLZO (lithium lanthanum zirconium oxide) particles (such as Figure 3 ), in the second film layer 32, each of the first LLZO particles has an overall radial length of less than 100 nanometers. The second inorganic ceramic 323 is used to enhance ionic conductivity and improve the mechanical strength of the entire second film layer 32. The total weight of the second inorganic ceramic 323 relative to the weight of the second polymer material 321 is between 8% and 20%.

[0031] The first LLZO particle can be lithium lanthanum zirconium oxide (Li7La3Zr2O 12 ), or lithium lanthanum zirconium oxide doped with at least one metal element. Preferably, the first LLZO particles are Cu-LLZO (copper-doped lithium lanthanum zirconium oxide) particles.

[0032] The purpose of coating the first LLZO particles with a dopamine layer 324 is to protect them because the PVDF-HFP in the second polymer material 321 easily reacts with the first LLZO particles, making film formation difficult. Furthermore, the first LLZO particles are susceptible to moisture, producing alkaline byproducts that easily react with PVDF-HFP to form a lithium fluoride. Dopamine is hydrophobic, so coating the first LLZO particles with the dopamine layer 324 prevents moisture from penetrating the particles. Furthermore, the functional groups of dopamine are compatible with the PAN in the second polymer material 321. In each first LLZO particle, the weight of the dopamine layer 324 is less than 5% of the weight of the first LLZO particle, and the thickness of the dopamine layer 324 is less than 3 nanometers.

[0033] The third film layer 33 comprises:

[0034] The third polymer material 331 serves as the substrate for the third film layer 33. The third polymer material 331 comprises a mixture of PEO (polyethylene oxide) and PAN, wherein the weight ratio of PEO to PAN is between 5:1 and 8:1. The PEO exhibits high stability and suitable ionic conductivity at the reduction potential of the negative electrode 10. PAN has excellent electronic and ionic conductivity, and therefore, the addition of PAN further enhances the overall performance of the PEO.

[0035] The PAN in the third polymer material 331 acts as a plasticizer and is dispersed in the PEO.

[0036] The additive 332 is FEC (fluoroethylene carbonate) dispersed in the third polymer material 331 to help the negative electrode 10 form a good ASEI (artificial solid electrolyte interface). The weight ratio of the additive 332 to the third polymer material 331 is less than 10%.

[0037] A third lithium salt 333 is dispersed within the third polymer material 331. The third lithium salt 333 is LiTFSI. During the formation or charge-discharge process, fluorine (F) on the LiTFSI and free lithium (Li) ions deposit on the surface of the negative electrode 10 to form LiF (lithium fluoride), which protects the negative electrode 10 and assists in the formation of ASEI. The primary purpose of the third lithium salt 333 is to lower the energy level of lithium ions during conduction within the polymer material, thereby increasing conductivity. The weight ratio of the third lithium salt 333 to the third polymer material 331 is between 1:3 and 1:9.

[0038] The third inorganic ceramic 334 is dispersed in the third polymer material 331. The third inorganic ceramic 334 is a plurality of second LLZO particles (such as Figure 4 ), in the third thin film layer 33, the overall radial size of each second LLZO particle is between 200 nanometers and 300 nanometers. The third inorganic ceramic 334 is used to improve ionic conductivity, so that the negative electrode 10 has good ionic conductivity and reduces the deposition of dead lithium, reduces the risk of lithium crystal formation and puncture, improves mechanical properties, and inhibits partial expansion of the negative electrode. Provides a stress source. The total weight of the third inorganic ceramic 334 and the weight ratio of the third polymer material 331 are between 10% and 20%. In each second LLZO particle, the weight of the dopamine layer 335 accounts for less than 5% of the weight of the second LLZO particle; the thickness of the dopamine layer 335 is less than 3 nanometers.

[0039] The second LLZO particles may be lithium lanthanum zirconium oxide (Li7La3Zr2O 12 ), or lithium lanthanum zirconium oxide doped with at least one metal element. Preferably, the second LLZO particles are Cu-LLZO (copper-doped lithium lanthanum zirconium oxide) particles.

[0040] The first film layer 31 does not contain ceramic particles and is made of a relatively soft material, thus providing better adhesion to the positive electrode. The first film layer 31 is made of a relatively soft polymer material that can fill the gaps between the positive electrodes 20. The lithium salt used in the first film layer 31 can reduce energy level differences and increase lithium ion conductivity.

[0041] The concentration of the first lithium salt 312 is higher than the concentration of the lithium salts in the other film layers of the dielectric film 30 (i.e., the second lithium salt 322 and the third lithium salt 333). The main purpose is to reduce the interfacial energy level that lithium ions must cross in the polymer materials of each film layer and increase conductivity.

[0042] In this embodiment, the lithium salt concentration in each thin film layer gradually decreases from the first thin film layer 31 to the third thin film layer 33 , so that when lithium ions are conducted, their energy level is reduced and the conduction is increased.

[0043] When the concentration of a single polymer material is too high, crystals can easily precipitate, preventing the polymer from effectively linking to form a film. The plasticizer in the polymer material can prevent crystal precipitation of each polymer material, supporting the structure of each polymer material and improving the overall structural properties of the polymer material. The plasticizer is a highly polar plasticizer, and its high polarity can facilitate the dissociation of each lithium salt, increasing the number of free lithium ions and thus improving lithium ion conductivity. Furthermore, the addition of inorganic ceramic materials to the second film layer 32 and the third film layer 33 can enhance lithium ion conductivity and mechanical properties.

[0044] The first film layer 31, the second film layer 32, and the third film layer 33 have a total thickness ranging from 12 microns to 24 microns. The second film layer 32 has a thickness ranging from 10 microns to 18 microns. The first film layer 31 and the third film layer 33 each have a thickness ranging from 1 micron to 3 microns.

[0045] The first thin film layer 31 and the third thin film layer 33 serve as interface bonding layers, such that the first thin film layer 31 can be bonded to the positive electrode 20 , and the third thin film layer 33 can be bonded to the negative electrode 10 .

[0046] The advantage of this case is that the design of this case adds a first film layer and a third film layer on both sides of the traditional single-layer dielectric film. The first film layer and the third film layer have a softer structure, so they can fill the gap between the positive and negative electrodes, and can also increase battery performance, reduce the risk of short circuits, improve battery yield, and improve the gap when the positive and negative electrodes are bonded.

[0047] In summary, this invention's user-friendly and thoughtful design meets practical needs. Its specific improvements over existing shortcomings offer significant breakthroughs compared to conventional technologies, providing a genuine improvement in efficacy that is not easily achievable. This invention has not been publicly disclosed or disclosed in domestic or international literature or the market, thus complying with patent law requirements.

[0048] The above detailed description is a specific description of one feasible embodiment of the present technical solution. However, this embodiment is not intended to limit the patent scope of the present technical solution. Any equivalent implementation or modification that does not deviate from the technical spirit of the present technical solution should be included in the patent scope of this case.

Claims

1. A dielectric film for solid-state and quasi-solid-state lithium batteries, characterized in that: The solid-state or quasi-solid-state battery structure is composed of a negative electrode, a positive electrode, and a dielectric film located between the positive and negative electrodes; wherein the negative electrode is filled with a negative electrode slurry as a binder; the negative electrode also contains a plurality of negative electrode particles; the positive electrode is filled with a positive electrode slurry as a binder; the positive electrode also contains a plurality of positive electrode particles; the dielectric film is located between the negative and positive electrodes, and includes a first film layer, a second film layer, and a third film layer, wherein the first film layer is connected to the positive electrode, the third film layer is connected to the negative electrode, and the second film layer is connected between the first film layer and the third film layer; The first film layer comprises: A first polymer material serves as the substrate of the first film layer; the first polymer material is a mixture of polyvinylidene fluoride-hexafluoropropylene, adiponitrile, glutaronitrile, and succinonitrile; the abbreviations of polyvinylidene fluoride-hexafluoropropylene are PVDF-HFP, adiponitrile are ADN, glutaronitrile are GLN, and succinonitrile are SN; the ADN, GLN, and SN in the first polymer material act as plasticizers and are dispersed in the PVDF-HFP to disperse the structure of the entire first polymer material, thereby reducing the precipitation of crystals of the first polymer material and promoting the dissociation of lithium salts, thereby making the entire first film layer easily conductive to lithium ions and easy to shape; A first lithium salt is dispersed in the first polymer material, wherein the first lithium salt is a mixture of lithium bis(oxalatoborate), lithium bis(trifluoromethylsulfonyl)amide, and lithium bis(fluorosulfonyl)imide; wherein lithium bis(oxalatoborate) is abbreviated as LiBOB, lithium bis(trifluoromethylsulfonyl)amide is abbreviated as LiTFSI, and lithium bis(fluorosulfonyl)imide is abbreviated as LiFSI; The second film layer comprises: A second polymer material serves as a substrate for the second film layer, wherein the second polymer material comprises a mixture of PVDF-HFP, polyacrylonitrile, and SN; wherein polyacrylonitrile is abbreviated as PAN; wherein the PAN and SN in the second polymer material act as plasticizers and are dispersed in the PVDF-HFP; and furthermore, the PAN and SN acting as plasticizers can help dissociate lithium salts in the second film layer, thereby improving the ionic conductivity of the membrane; A second lithium salt is dispersed in the second polymer material, wherein the second lithium salt comprises LiFSI and LiTSFI; A second inorganic ceramic is dispersed in the second polymer material, wherein the second inorganic ceramic is a plurality of first lithium lanthanum zirconium oxide particles coated with a dopamine layer; wherein the abbreviation of lithium lanthanum zirconium oxide is LLZO; The third film layer comprises: A third polymer material serves as a substrate for the third film layer; the third polymer material comprises a mixture of polyethylene oxide and PAN, wherein polyethylene oxide is abbreviated as PEO. PEO has high stability and suitable ionic conductivity at the negative electrode reduction potential; PAN has good electronic and ionic conductivity, and therefore, the overall performance of PEO can be further improved when mixed with PAN; the PAN in the third polymer material acts as a plasticizer and is dispersed in the PEO; A third lithium salt is dispersed in the third polymer material; wherein the third lithium salt is LiTFSI; and The third inorganic ceramic is dispersed in the third polymer material. The third inorganic ceramic is a plurality of second LLZO particles coated with a dopamine layer. The third inorganic ceramic is used to improve ion conductivity.

2. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein: Wherein in the first film layer: The weight ratio of the ADN, the GLN, and the SN is between 1:2:7 and 0.5:1:9.5; wherein the ratio of the weight of the PVDF-HFP to the total weight of the ADN, the GLN, and the SN is 12:1 to 8:1; wherein the weight ratio of the total weight of the first lithium salt to the total weight of the first polymer material is between 1:2.5 and 1:5; and The ratio of the total weight of the LiTFSI and the LiFSI to the weight of the LiBOB is 2:3; and the weight ratio of the LiFSI to the LiTFSI is 2:

1.

3. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein in the second film layer: The weight ratio of the PVDF-HFP weight to the PAN weight to the SN weight in the second polymer material is between 8:1.2:1 and 8:1:1.6; wherein the weight ratio of the LiFSI to the LiTSFI is 1:2; wherein the weight ratio of the total weight of the second lithium salt to the total weight of the second polymer material is between 1:3 and 1:9; The total weight of the second inorganic ceramic is in a ratio of 8% to 20% relative to the weight of the second polymer material.

4. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein: wherein the overall radial size of each of the first LLZO particles is less than 100 nanometers; In each of the first LLZO particles, the weight of the dopamine layer accounts for less than 5% of the weight of the first LLZO particle, and the thickness of the dopamine layer is less than 3 nanometers.

5. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein: In the third film layer: The weight ratio of the PEO to the PAN is between 5:1 and 8:1; and The weight ratio of the total weight of the third lithium salt to the weight of the third polymer material is between 1:3 and 1:

9.

6. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein: The third film layer further includes an additive, which is fluoroethylene carbonate dispersed in the third polymer material, and is used to help the negative electrode form a good artificial solid electrolyte interface; wherein, the abbreviation of fluoroethylene carbonate is FEC.

7. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 6, wherein: The weight ratio of the additive to the third polymer material is less than 10%.

8. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein: The first LLZO particles and the second LLZO particles are Cu-LLZO, ie, copper-doped lithium lanthanum zirconium oxide particles.

9. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein: wherein the overall radial size of each of the second LLZO particles is between 200 nanometers and 300 nanometers; The weight ratio of the total weight of the third inorganic ceramic to the weight of the third polymer material is between 10% and 20%.

10. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein: The lithium salt concentration in the first thin film layer is greater than that in the second thin film layer; and the lithium salt concentration in the second thin film layer is greater than that in the third thin film layer, thereby increasing lithium ion conduction.

11. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein: The overall thickness of the first film layer, the second film layer and the third film layer is between 12 microns and 24 microns; the thickness of the second film layer is between 10 microns and 18 microns; and the thickness of the first film layer and the third film layer is between 1 micron and 3 microns.

12. The dielectric film for solid-state and quasi-solid-state lithium batteries according to claim 1, wherein: The first film layer and the third film layer serve as interface bonding layers.

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