Battery structure with a single layer dielectric film coating organic composite ceramic particles

Abstract

A battery structure is provided that includes a single layer dielectric film coating organic composite ceramic particles. [Solution] The battery structure of the present invention includes a negative electrode (10), a positive electrode (20), and a dielectric film (30) positioned between the positive and negative electrodes. The dielectric film includes a polymer material (321) serving as the base of the dielectric film, the polymer material including a mixture of polyvinylidene fluoride-hexafluoropropylene copolymer, hydrogenated nitrile butadiene rubber, and succinonitrile. A lithium salt (322) is dispersed in the polymer material. A plurality of composite ceramic particles (100) are dispersed in the polymer material. Each composite ceramic particle includes ceramic particles for guiding and dispersing lithium ions, a dopamine layer coating the outer surface of the ceramic particle to form a primary particle, and a PVDF layer coating the outer surface of the primary particle.

Description

[Technical Field]

[0001] The present invention relates to a dielectric film for a battery, and more particularly to a battery structure including a single-layer dielectric film coating organic composite ceramic particles. [Background technology]

[0002] A conventional solid or semi-solid battery structure consists of an anode, a cathode, and a dielectric film located between the cathode and anode. The anode is filled with an anode slurry as a binder, with a plurality of anode particles dispersed within the anode slurry. The cathode is filled with a cathode slurry as a binder, with a plurality of cathode particles dispersed within the cathode slurry. The dielectric film is used to separate and connect the anode and cathode. Summary of the Invention [Problem to be solved by the invention]

[0003] However, when ordinary ceramic particles get wet, they tend to generate alkaline by-products, which can easily cause a lithium fluoride reaction with PVDF-HFP, leading to deterioration of the entire battery slurry and the possibility of the entire battery shorting out.Dopamine is hydrophobic, so in conventional technology, the outer surfaces of the ceramic particles are coated with a dopamine layer to make it difficult for moisture to penetrate the ceramic particles.

[0004] In addition, the dopamine layer cannot completely cover the outer surfaces of the ceramic particles, so that some of the surfaces of the ceramic particles are exposed, which may further deteriorate the battery slurry.

[0005] Therefore, the present inventors believed that the above drawbacks could be improved, and after extensive research, they came up with the present invention, which rationally and effectively improves the problem.

[0006] The present invention has been made to solve the above-mentioned problems of the prior art. That is, the object of the present invention is to provide a battery structure having a single-layer dielectric film covering organic composite ceramic particles. [Means for solving the problem]

[0007] To achieve the above object, a battery structure having a single-layer dielectric film covering organic composite ceramic particles according to one embodiment of the present invention is provided in which the outer surfaces of the ceramic particles that originally cover the dopamine layer are further coated with the PVDF layer as a protective layer, and the PVDF layer further protects the primary particles inside, so that when the composite ceramic particles enter the dielectric film, they do not react with the polymer material in the dielectric film, which would cause deterioration of the positive electrode slurry.

[0008] At least the following points will become clear from the description and drawings to be described later. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram illustrating an embodiment of a battery structure including a single-layer dielectric film covering organic composite ceramic particles in accordance with the present invention; [Figure 2] 1 is a schematic cross-sectional view of a composite ceramic particle according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described below with reference to the accompanying drawings, in which: FIG. 1 is a block diagram of a conventional optical fiber cable; FIG. 2 is a block diagram of a conventional optical fiber cable;

[0011] First, an embodiment of a battery structure including a single-layer dielectric film covering organic composite ceramic particles according to the present invention will be described with reference to FIGS. 1 and 2. FIG.

[0012] The battery structure including the single-layer dielectric film coated with the organic composite ceramic particles of the present invention is similar to that of a typical solid or semi-solid battery, which includes an anode 10 and a cathode 20. The dielectric film 30 of the present invention is located between the cathode 20 and the anode 10 (see Figure 2). The anode 10 is filled with a binder anode slurry, which is distributed among multiple anode particles (e.g., SiC (silicon carbide) particles with a tin layer) within the anode slurry. The outer surfaces of the anode particles accommodate lithium ions and facilitate uniform lithium ion flow through the anode. The anode particles undergo partial side reactions with the lithium ions, reducing the number of available lithium ions and, over the long term, reducing the overall battery capacity. The cathode 20 is filled with a binder anode slurry, which is distributed among multiple positive electrode particles within the cathode slurry. The cathode slurry and the positive electrode particles undergo side reactions with passing lithium ions, resulting in the depletion of available lithium ions.

[0013] The dielectric film 30 according to the present invention is located between the negative electrode 10 and the positive electrode 20 and is used to separate and connect the negative electrode 10 and the positive electrode 20. The thickness of the dielectric film 30 ranges from 10 μm to 18 μm (see FIGS. 1 and 2).

[0014] The dielectric film 30 mainly comprises the following components.

[0015] <Polymer Materials 321> As the base material of the dielectric film 30, the polymer material 321 includes a mixture of PVDF-HFP (Polyvinylidene fluoride-hexafluoropropylene copolymer), HNBR (hydrogenated nitrile butadiene rubber), and SN (Succinonitrile). The polymer material 321 may further include PDADMA-TFSI (poly(diallyldimethylammonium) bis(trifluoromethanesulfonyl)imide). The polymer material 321 is used as a base material. In the polymer material 321, the weight ratio of the PVDF-HFP, the HNBR, and the SN is in the range of 1:0.0625-0.625:0.125-12.8, i.e., the weight ratio of the PVDF-HFP, the HNBR, and the SN is A:B:C. Here, B is in the range of 0.0625-0.625 times A, and C is in the range of 0.125-12.8 times A. Hereinafter, the same mathematical formulas have the same mathematical meaning, and therefore the explanation thereof will not be repeated here.

[0016] The SN in the polymer material 321 is dispersed in the PVDF-HFP as a plasticizer, which functions to disperse the overall structure of the polymer material 321 and reduce crystalline precipitation of the polymer material 321. The SN aids in the dissociation of the lithium salt in the dielectric film 30 (i.e., lithium salt 322 described below) and improves ionic conductivity.

[0017] <Lithium salt 322> The lithium salt 322 is dispersed in the polymer material 321 and includes LiFSI (F2LiNO4S2, Lithium bis(fluorosulfonyl)imide), LiTSFI (LiN(CF3SO2)2, Lithium bis(trifluoromethanesulfonyl)imide), and lithium LiCl (LiCl). In the dielectric film 30, the weight ratio of the LiFSI, LiTSFI, and LiCl is 1:2:0.1. The lithium salt 322 is used to lower the energy level and increase stability and conductivity when conducting lithium ions through each of the polymer materials. The weight ratio of the total weight of the lithium salt 322 to the total weight of the polymer material 321 is in the range of 1:3 to 1:9.

[0018] <Multiple composite ceramic particles 100> A plurality of the composite ceramic particles 100 are dispersed in the polymer material 321 to improve the ionic conductivity and the mechanical strength of the entire dielectric film 30. The weight percentage of the composite ceramic particles 100 in the polymer material 321 is in the range of 8% wt to 20% wt of the total weight.

[0019] Referring to FIG. 2, each of the composite ceramic particles 100 mainly has the following components.

[0020] <Ceramic particles 32> The ceramic particles 32 have high ionic conductivity for lithium ions. Therefore, when the lithium ions pass through the dielectric film 30, the ceramic particles 32 serve to guide and disperse the lithium ions, allowing the formation of uniformly distributed lithium ion channels within the dielectric film 30. The particle size of the ceramic particles 32 is less than 100 nm.

[0021] <Dopamine Layer 34> Coat the outer surface of the ceramic particles 32 so as to form primary particles 35. The dopamine layer 34 is composed of polydopamine molecules. The thickness of the dopamine layer 34 ranges between 2 nm and 15 nm. The bonding method between the polydopamine molecules and the ceramic particles 32 is well known in the prior art, so the description thereof will not be repeated here.

[0022] <PVDF (polyvinylidene difluoride) layer 36> Coat the outer surface of the primary particles 35. The thickness of the PVDF layer 36 ranges between 10 nm and 100 nm, and the particle size of the entire composite ceramic particles 100 is less than 300 nm.

[0023] The ceramic particles 32 are at least one of an oxide having lithium ion conduction ability (ion conductivity exceeding 10 -5 cm 2 / s (diffusion coefficient)), an oxide having a garnet structure, or an oxide having a perovskite structure. The oxide having lithium ion conduction ability is, for example, lithium aluminium germanium phosphate (LAGP) having a NASICON (sodium (Na) super ionic conductor) structure, and the oxide having a garnet structure is, for example, lithium lanthanum zirconium oxide (Li7La3Zr2O 12 , lithium lanthanum zirconium oxide, LLZO), and the oxide having a perovskite structure is, for example, lithium lanthanum titanium oxide (LLTO).

[0024] When the ceramic particles 32 are made of LLZO, the LLZO material is formed from at least one selected from the group consisting of LLZO, Ga-LLZO (Ga-doped LLZO, gallium-doped lithium-lanthanum-zirconium oxide), Cu-LLZO (Cu-doped LLZO, copper-doped lithium-lanthanum-zirconium oxide), Ta-LLZO (Ta-doped LLZO, tantalum-doped lithium-lanthanum-zirconium oxide), Sr-LLZO (Sr-doped LLZO, strontium-doped lithium-lanthanum-zirconium oxide), and Al-LLZO (Al-doped LLZO, aluminum-doped lithium-lanthanum-zirconium oxide).

[0025] When the ceramic particles 32 are made of LAGP, the LAGP is Li 1+x Al x Ge 2-x (PO4)3 or Li 1+x+y Al x Ge 2-x-y-z M y N z (PO4)3, where x is in the range of 0.1 to 0.8, y is in the range of 0 to 0.2, and z is in the range of 0 to 0.2. M is selected from Sc 3+ (Scandium ion), Y 3+ (yttrium ion), Ga 3+ (Gallium ion), In 3+ (indium ion), La 3+ (lanthanum ion), and N is Zr 4+ (zirconium ion), Si 4+ (silicon ion), Sn 4+ (tin ion) and other tetravalent cations.

[0026] Therefore, the polymer material 321 in the dielectric film 30 primarily serves to disperse, adhere, and support the materials in the dielectric film 30. To enable high-speed lithium ion conduction in the dielectric film 30 and improve the battery's electrical conduction efficiency, the composite ceramic particles 100 are added to the dielectric film 30. Because the composite ceramic particles 100 have high ionic conductivity for lithium ions, the dispersed composite ceramic particles 100 guide the lithium ions as they pass through the dielectric film 30, dispersing the lithium ion channels and preventing abnormal accumulation of lithium ions within the dielectric film 30 and causing side reactions with the dielectric film 30. More specifically, to enhance lithium ion conduction, the lithium salt 322 is further added to the polymer material 321, thereby increasing the overall density of lithium ions. When a potential difference exists across the dielectric film 30, lithium ions can enter and exit the dielectric film 30 at high speed, improving the lithium ion conduction rate.

[0027] When wet, the ceramic particles 32 tend to generate alkaline by-products, which can easily cause a lithium fluorination reaction with the PVDF-HFP in the dielectric film 30, leading to deterioration of the entire battery slurry and potentially short-circuiting the entire battery. Because dopamine is hydrophobic, coating the outer surfaces of the ceramic particles 32 with the dopamine layer 34 makes it difficult for moisture to penetrate the ceramic particles 32. The dopamine layer 34 may not completely cover the outer surfaces of the ceramic particles 32, leaving some of the surface of the ceramic particles 32 exposed. Therefore, by further coating the outer surfaces of the primary particles 35 with the PVDF layer 36 as a protective layer, the PVDF layer 36 further protects the internal primary particles 35. This prevents the composite ceramic particles 100 from reacting with the polymer material 321 in the dielectric film 30 when they penetrate into the dielectric film 30, thereby preventing deterioration of the positive electrode slurry.

[0028] The present invention has been described above based on the embodiments. These embodiments are merely examples, and it will be understood by those skilled in the art that various modifications are possible in the combination of each component and each treatment process, and that such modifications are also within the scope of the present invention. [Explanation of symbols]

[0029] 10 negative electrode 20 positive electrode 30 Dielectric Film 32 Ceramic particles 34 Dopamine Layer 35 Primary particles 36 PVDF layers 100 Composite Ceramic Particles 321 Polymer Materials 322 Lithium Salts

Claims

1. A battery structure comprising a single-layer dielectric film coating organic composite ceramic particles, the battery structure including a negative electrode, a positive electrode, and a dielectric film located between the positive electrode and the negative electrode; The dielectric film is a polymer material used as a base material for the dielectric film, the polymer material comprising a mixture of PVDF-HFP, HNBR, and SN, the polymer material acting as an adhesive and supporting materials in the dielectric film, the SN in the polymer material being dispersed in the PVDF-HFP as a plasticizer, the function of which is to reduce crystalline precipitation of the polymer material by dispersing the entire structure of the polymer material, and the SN being used to assist dissociation of lithium salt in the dielectric film and increase ionic conductivity; a lithium salt dispersed in the polymer material, the lithium salt being used to lower the energy level and at the same time increase stability and improve conductivity when conducting lithium ions through each of the polymer materials, the lithium salt including LiFSI, LiTSFI, and LiCl; a plurality of composite ceramic particles dispersed in the polymer material to enhance ionic conductivity and mechanical strength of the entire dielectric film; Each of the composite ceramic particles is Ceramic particles having high ionic conductivity to lithium ions, which are used to guide and distribute lithium ions and form uniformly distributed lithium ion channels within the dielectric film; a dopamine layer comprising polydopamine molecules coating the outer surface of the ceramic particles to form primary particles; a PVDF layer covering the outer surface of the primary particles, the function of the PVDF layer being to prevent a side reaction between the ceramic particles and the polymer material, thereby preventing the performance of the entire ceramic particles from being affected; The plurality of composite ceramic particles are dispersed among the polymer material, and the lithium salt is distributed among the polymer material to increase the overall density of lithium ions, so that when there is a potential difference between both ends of the dielectric film, lithium ions can enter and exit at high speed, accelerating the conduction rate of lithium ions.

2. 2. The battery structure comprising a single-layer dielectric film covering organic composite ceramic particles according to claim 1, wherein the ceramic particles are formed of at least one of an oxide having lithium ion conductivity, an oxide having a garnet structure, and an oxide having a perovskite structure.

3. 3. A battery structure comprising a single-layer dielectric film covering organic composite ceramic particles according to claim 2, wherein the oxide having lithium ion conductivity is selected from the group consisting of germanium aluminum lithium phosphate having a NASICON structure.

4. 3. A battery structure comprising a single-layer dielectric film covering organic composite ceramic particles according to claim 2, characterized in that the oxide having the garnet structure is selected from lithium lanthanum zirconium oxide, and the oxide having the perovskite structure is selected from lithium lanthanum titanium oxide.

5. 2. A battery structure comprising a single-layer dielectric film covering organic composite ceramic particles according to claim 1, wherein when the ceramic particles are made of LLZO, the LLZO material is formed by selecting at least one of LLZO, Ga-LLZO, Cu-LLZO, Ta-LLZO, Sr-LLZO, and Al-LLZO.

6. When the ceramic particles are composed of LAGP, the LAGP is Li １＋ｘ Al ｘ Ge ２-ｘ (P.O. ４ ) ３ or Li １＋ｘ＋ｙ Al ｘ Ge ２-ｘ-ｙ-ｚ M ｙ N ｚ (P.O. ４ ) ３ wherein x is in the range of 0.1 to 0.8, y is in the range of 0 to 0.2, z is in the range of 0 to 0.2, M is a trivalent cation, and N is a tetravalent cation.

7. The trivalent cation is Sc ３＋ (Scandium ion), Y ３＋ (yttrium ion), Ga ３＋ (Gallium ion), In ３＋ (indium ions), and La ３＋ (lanthanum ion), and the tetravalent cation is selected from Zr ４＋ (zirconium ion), Si ４＋ (silicon ions), and Sn ４＋ 7. A battery structure comprising a single-layer dielectric film covering the organic composite ceramic particles according to claim 6, wherein the dielectric film is selected from the group consisting of tin ions.

8. 2. The battery structure having a single-layer dielectric film covering organic composite ceramic particles according to claim 1, wherein the thickness of the dielectric film ranges between 10 μm and 18 μm.

9. 2. The battery structure comprising a single-layer dielectric film coating organic composite ceramic particles according to claim 1, wherein in the polymer material, the weight ratio of the PVDF-HFP, the HNBR, and the SN is in the range of 1:0.0625-0.625:0.125-12.

8.

10. 2. The battery structure comprising a single-layer dielectric film coating organic composite ceramic particles according to claim 1, wherein the polymer material further comprises PDADMA-TFSI.

11. 2. The battery structure comprising a single-layer dielectric film coating organic composite ceramic particles according to claim 1, characterized in that the weight percentage of the total weight of the composite ceramic particles in the polymer material is in the range of between 8% wt and 20% wt.

12. 2. The battery structure comprising a single-layer dielectric film covering organic composite ceramic particles according to claim 1, wherein the particle size of the ceramic particles is less than 100 nm, the thickness of the PVDF layer is in the range of 10 nm to 100 nm, the thickness of the dopamine layer is in the range of 2 nm to 15 nm, and the particle size of the composite ceramic particles is less than 300 nm.

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