Positive electrode plates with composite ceramic particles enclosed by organic compounds

Abstract

Positive electrode plate with composite ceramic particles encapsulated by organic compounds; a positive electrode mass used in a positive electrode plate; the positive electrode plate comprises: a positive electrode substrate, which serves as a carrier for the material of a positive electrode; a layer of positive electrode mass coated onto the positive electrode substrate; wherein the layer of positive electrode mass is formed by the positive electrode mass; the positive electrode mass comprises: a multitude of positive electrode particles which serve to store or release lithium ions; wherein each of the positive electrode particles represents an active material; an adhesive formed from a polymer material; a variety of conductive agents that increase the electrical conductivity of the positive electrode paste; a multitude of composite ceramic particles which serve to guide the lithium ions to dispersing lithium ion channels, thereby preventing side reactions between the lithium ions and the positive electrode mass due to abnormal deposition of the lithium ions in the positive electrode paste; wherein each of the composite ceramic particles comprises the following: a ceramic particle; A dopamine layer surrounds the outer surface of the ceramic particle, forming a first particle. A PVDF layer surrounds the outer surface of the first particle. The dopamine layer, the PVDF layer, and the ceramic particle together form the composite ceramic particle. The positive electrode particles are distributed within the positive electrode material layer. The conductive materials and the composite ceramic particles are distributed between the positive electrode particles. The adhesive serves to bond the positive electrode particles, the conductive materials, and the composite ceramic particles together.

Description

AREA OF INVENTION

[0001] The invention relates to a positive electrode plate, in particular a positive electrode plate with composite ceramic particles which are enclosed by organic compounds. BACKGROUND OF THE INVENTION

[0002] A typical battery consists primarily of positive and negative electrodes immersed in electrolyte. In current technology, ceramic particles are added to the electrode to increase its ionic conductivity. Since the ceramic particles exhibit high lithium-ion conductivity, the lithium-ion channels within the electrode can be distributed by guiding the dispersed ceramic particles as the lithium ions pass through the electrode, resulting in a uniform distribution of lithium-ion channels.

[0003] Conventionally, the surface of ceramic particles contains many alkaline functional groups (such as OH-, Li₂O, etc.). Therefore, the positive electrode compound added during electrode fabrication exhibits strong alkalinity due to the reaction between the ceramic particles and the solvent. This leads to damage of the positive electrode particles within the positive electrode compound and the positive electrode compound itself, complicating the fabrication process and likely resulting in lower-than-expected electrochemical properties of the fabricated positive electrode plate. Prior art has shown that ceramic particles can be protected by coating their outer surface with a dopamine layer. However, the dopamine layer cannot completely encapsulate the outer surface of the ceramic particles, leaving some parts of the outer surface exposed.During the production of the electrode compound, a solvent is added. When the electrode compound is applied to the electrode substrate and a subsequent step is carried out, the solvent in the electrode compound evaporates, forming an electrode compound layer that is deposited onto the electrode substrate, thus creating an electrode plate. No solvent is present within the electrode compound layer itself. SUMMARY OF THE INVENTION

[0004] To overcome the aforementioned shortcomings of the prior art, the object of the invention is to provide a positive electrode plate with composite ceramic particles encapsulated by organic compounds, wherein a further PVDF layer is applied as a protective layer to the outer surface of the ceramic particles, which are initially encapsulated by a dopamine layer. Thus, during the fabrication of the electrode plate, the PVDF layer provides additional protection to the ceramic particles encapsulated by the dopamine layer. When the multitude of composite ceramic particles are added to the positive electrode mass along with the solvent, they do not react with the solvent in the positive electrode mass and do not damage it. The electrode with the composite ceramic particles therefore exhibits improved stability. BRIEF DESCRIPTION OF THE IMAGES Fig. shows an application of the invention. Fig. shows a cross-sectional view illustrating the structure of the invention. DETAILED DESCRIPTION OF THE INVENTION

[0005] With reference to the Fig. The invention describes a positive electrode plate with composite ceramic particles 100, which are enclosed by organic compounds. A positive electrode mass 22 is used in the positive electrode plate. The positive electrode plate comprises the following elements: A positive electrode substrate 21 serves as a carrier for the material of a positive electrode 20. A positive electrode mass layer 23 is applied to the positive electrode substrate 21, thus forming the positive electrode plate. The positive electrode mass layer 23 is formed by the positive electrode mass 22. The positive electrode mass 22 comprises the following elements: A multitude of positive electrode particles 10 serve to store or release lithium ions. The positive electrode particles 10 consist of LCO particles (LiCoO2) and NCM particles (lithium nickel manganese cobalt oxide). Each of the positive electrode particles 10 represents an active material. The weight fraction of the positive electrode particles 10 in the positive electrode sludge layer 23 is between 92 and 98 wt%, where wt% means weight percent. An adhesive 12 consists of a polymer material. The polymer material consists of at least one of the materials PVDF (polyvinylidene fluoride) or PVDF-HFP (polyvinylidene fluoride-hexafluoropropylene copolymer). A variety of conductive substances 14 consist of at least one of the following materials: Carbon nanotubes, graphene, and amorphous carbon. The amorphous carbons are like super-powered P. The conductivity agents 14 increase the electrical conductivity of the positive electrode mass 22. Several composite ceramic particles 100 conduct the lithium ions to dispersed lithium ion channels, thereby preventing side reactions between the lithium ions and the positive electrode mass 22 due to abnormal deposition of lithium ions in the positive electrode mass 22. Each of the ceramic composite particles 100 has the following properties: A ceramic particle 15 has a size of less than 100 nm. A dopamine layer 35 surrounds the outer surface of the ceramic particle 15, thus forming a first particle 110. A PVDF layer 41 encloses the outer surface of the first particle 110. The dopamine layer 35, the PVDF layer 41, and the ceramic particle 15 form the composite ceramic particle 100. The thickness of the PVDF layer 41 is 10 nm to 100 nm. The thickness of the dopamine layer 35 is 2 nm to 15 nm. The particle size of the composite ceramic particle 100 is less than 300 nm. The positive electrode particles 10 are distributed in the positive electrode mass layer 23. The conductivity agents 14 and the composite ceramic particles 100 are dispersed between the positive electrode particles 10. The adhesive 12 serves to bond the positive electrode particles 10, the conductivity agents 14, and the composite ceramic particles 100 together. The ceramic particle 15 consists of at least one of the following materials: ceramic oxides, oxides with a garnet structure, or oxides with a perovskite structure. The lithium ion conductivity of the ceramic oxides is greater than 10. -5 cm 2 / s (diffusion coefficient). The ceramic oxides are LAGPs (lithium aluminum germanium phosphate) with NASICON structures (sodium superion conductors). The oxides with garnet structures can be LLZOs (Li7La3Zr2O). 12 The ceramic particle 15 can be formed by combining the above-mentioned materials in any desired ratio. (Lithium lanthanum zirconium oxide) or oxides with perovskite structures (LLTOs - lithium lanthanum titanium oxide). The ceramic particle 15 can consist of at least one of the following materials: LLZO (Li7La3Zr2O 12 ), Ga-LLZO (gallium-doped LLZO), Cu-LLZO (copper-doped LLZO), Ta-LLZO (tantalum-doped LLZO), Sr-LLZO (strontium-doped LLZO) and Al-LLZO (aluminium-doped LLZO).

[0006] If the ceramic particle 15 consists of LAGP, the LAGP is made of 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 selected where 0.1≤x≤0.8, 0≤y≤0.2, 0≤z≤0.2, M a trivalent cation (such as scandium cation (Sc 3+ ), Yttrium cation (Y 3+ ), Gallium cation (Ga 3+ ), Indium cation (In 3+ ) or lanthanum cation (La 3+ )) and N a tetravalent cation (such as zirconium cation (Zr) 4+ ), silicon cation (Si 4+ ) or tin cation (Sn 4+ )) is.

[0007] The positive electrode mass 22 also contains the following elements: Several lithium salts 16 consisting of at least one of the following substances: LiTFSI(LiN(CF3SO2)2), LiFSI, LiF and BMITFSI (1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide). The lithium salts 16 serve to improve the electrochemical quality of the battery.

[0008] The weight ratio of the adhesive 12 to the positive electrode particles 10 is between 0.005 and 0.035; the weight ratio of the conductivity agents 14 to the positive electrode particles 10 is between 0.005 and 0.028; the weight ratio of the composite ceramic particles 100 to the positive electrode particles 10 is between 0.001 and 0.016; and the weight ratio of the lithium salts 16 to the positive electrode particles 10 is between 0.002 and 0.028.

[0009] In the prior art, ceramic particles are produced by coating their outer surface with a dopamine layer. However, the dopamine layer cannot completely encapsulate the outer surface of the ceramic particles, leaving parts of the outer surface exposed. When electrode plates are produced according to the prior art, these exposed parts of the second composite particle react with the solvent of the positive electrode mass, resulting in a strongly alkaline positive electrode mass when several dopamine-coated ceramic particles are added.

[0010] A positive electrode plate with composite ceramic particles encapsulated by organic compounds thus comprises the following: a positive electrode substrate; a layer of a positive electrode mass coated onto the positive electrode substrate; several positive electrode particles; an adhesive formed from a polymer material; several conductive agents serving to increase the electrical conductivity of the positive electrode mass; several composite ceramic particles; wherein each composite ceramic particle comprises a ceramic particle; a dopamine layer enclosing an outer surface of the ceramic particle; a PVDF layer enclosing an outer surface of the first particle; wherein the dopamine layer, the PVDF layer, and the ceramic particle together form a composite ceramic particle.

[0011] In describing the invention, it is obvious that it can be varied in many ways. Such variations do not constitute a departure from the spirit and scope of the invention, and all modifications obvious to a person skilled in the art are intended to fall within the scope of protection of the following claims.

Claims

[1] Positive electrode plate with composite ceramic particles enclosed by organic compounds; a positive electrode mass used in a positive electrode plate; the positive electrode plate comprises: a positive electrode substrate, which serves as a carrier for the material of a positive electrode; a layer of positive electrode mass coated onto the positive electrode substrate; wherein the layer of positive electrode mass is formed by the positive electrode mass; the positive electrode mass comprises: a multitude of positive electrode particles which serve to store or release lithium ions; wherein each of the positive electrode particles represents an active material; an adhesive formed from a polymer material; a variety of conductive agents that increase the electrical conductivity of the positive electrode paste; a multitude of composite ceramic particles which serve to guide the lithium ions to dispersing lithium ion channels, thereby preventing side reactions between the lithium ions and the positive electrode mass due to abnormal deposition of the lithium ions in the positive electrode paste; wherein each of the composite ceramic particles comprises the following: a ceramic particle; A dopamine layer surrounds the outer surface of the ceramic particle, forming a first particle. A PVDF layer surrounds the outer surface of the first particle. The dopamine layer, the PVDF layer, and the ceramic particle together form the composite ceramic particle. The positive electrode particles are distributed within the positive electrode material layer. The conductive materials and the composite ceramic particles are distributed between the positive electrode particles. The adhesive serves to bond the positive electrode particles, the conductive materials, and the composite ceramic particles together. [2] Positive electrode mass according to claim 1, wherein the positive electrode mass additionally contains a plurality of lithium salts which improve the electrochemical quality of the battery. [3] Positive electrode mass according to claim 2, wherein the lithium salts consist of at least one of the following substances: LiTFSI (LiTFSI(LiN(CF3SO2)2), LiFSI, LiF and BMITFSI (1-Butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide). [4] Positive electrode mass according to claim 1, wherein the positive electrode particles are selected from LCO particles (LiCoO2) and NCM particles (lithium nickel manganese cobalt oxide). [5] Positive electrode mass according to claim 1, wherein the weight ratio of the adhesive to the positive electrode particles is between 0.005 and 0.035; the weight ratio of the conductive means to the positive electrode particles is between 0.005 and 0.028; and the weight ratio of the composite ceramic particles to the positive electrode particles is between 0.001 and 0.

016. [6] Positive electrode mass according to claim 2, wherein the weight ratio of the lithium salts to the positive electrode particles is between 0.002 and 0.

028. [7] Positive electrode mass according to claim 1, wherein the polymer material consists of at least one of the following materials: PVDF (polyvinylidene difluoride) or PVDF-HFP (polyvinylidene fluoride hexafluoropropylene copolymer). [8] Positive electrode mass according to claim 1, wherein the conductive medium consists of at least one of the following materials: carbon nanotubes, graphene or amorphous carbons. [9] Positive electrode mass according to claim 1, wherein the particle size of the composite ceramic particles is less than 300 nm. [10] Positive electrode mass according to claim 1, wherein the ceramic particles consist of at least one of the following materials: ceramic oxides, garnet-structured oxides or perovskite-structured oxides. [11] Positive electrode mass according to claim 10, wherein the ceramic oxides are LAGP (lithium aluminum germanium phosphate) with NASICON structures (sodium (Na) superion conductors). [12] Positive electrode mass according to claim 1, wherein the ceramic particles consist of LAGPs and the LAGPs consist of 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 are selected, where 0.1≤x≤0.8, 0≤y≤0.2, 0≤z≤0.2, M is a trivalent cation and N is a tetravalent cation. [13] Positive electrode mass according to claim 12, wherein the trivalent cation is from scandium cation (Sc 3+ ), Yttrium cation (Y 3+ ), Gallium cation (Ga 3+ ), Indium cation (In 3+ ) or lanthanum cation (La 3+ ) is selected. [14] Positive electrode mass according to claim 12, wherein the tetravalent cation is selected from zirconium cation (Zr 4+ ), silicon cation (Si 4+) or tin cation (Sn 4+ ). [15] Positive electrode mass according to claim 10, wherein the oxides have garnet structures LLZO (Li7La3Zr2O 12 , lithium lanthanum zirconium oxide) and the oxides with perovskite structures LLTO (lithium lanthanum titanium oxide). [16] Positive electrode mass according to claim 1, wherein the ceramic particle consists of at least one of the following materials: LLZO, Ga-LLZO, Cu-LLZO, Ta-LLZO, Sr-LLZO or Al-LLZO.

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