Thermosetting binder and ceramic particle coating for enhancing stability of lithium ion battery

Abstract

The present disclosure provides thermoset binders and ceramic particle coatings that enhance the stability of lithium ion batteries. A negative electrode for a lithium ion battery includes: a negative electrode current collector; a negative electrode active layer disposed over the negative electrode current collector; and a layer containing ceramic particles, the layer containing ceramic particles being disposed over the negative electrode active layer. The negative electrode active layer is made of a negative electrode active material. Advantageously, the ceramic particle-containing layer consists of ceramic particles and a binder, where the binder consists of residues of a crosslinkable monomer.

Description

Technical Field

[0001] In at least one aspect, a negative electrode active material for a rechargeable lithium ion battery is provided. Background Art

[0002] Lithium-ion batteries consist of an anode, a cathode, an electrolyte and a separator. The anode is mainly composed of graphite, in which lithium ions are embedded in the graphite layer during the charging process. During the initial charging step, an SEI (solid electrolyte interface) layer is created on the anode surface and protects the electrolyte from reductive decomposition. It may be desirable to have a stable SEI layer.

[0003] Therefore, there is a need for improved negative electrodes for lithium-ion batteries. Summary of the invention

[0004] In at least one aspect, a negative electrode for a lithium ion battery is provided. The negative electrode comprises: a negative electrode current collector; a negative electrode active layer, the negative electrode active layer being disposed above the negative electrode current collector; and a ceramic particle-containing layer, the ceramic particle-containing layer being disposed above the negative electrode active layer. The negative electrode active layer is composed of a negative electrode active material. Advantageously, the ceramic particle-containing layer is composed of ceramic particles and a binder, wherein the binder is composed of residues of a crosslinkable monomer (e.g., a crosslinkable monomer that forms a crosslinked bond during cell processing).

[0005] On the other hand, a rechargeable lithium-ion battery is provided. The rechargeable lithium-ion battery includes at least one lithium-ion battery cell. Each lithium-ion battery cell includes: a negative electrode collector; a negative electrode active layer, the negative electrode active layer is arranged above the negative electrode collector; and a ceramic particle-containing layer, the ceramic particle-containing layer is arranged above the negative electrode active layer. The negative electrode active layer is composed of a negative electrode active material. Advantageously, the ceramic particle-containing layer is composed of ceramic particles and a binder, wherein the binder is composed of residues of a cross-linkable monomer. Each lithium-ion battery cell also includes: a positive electrode, the positive electrode includes a positive electrode active material; and an electrolyte, the electrolyte contacts the negative electrode and the positive electrode.

[0006] In another aspect, a method is provided for introducing a ceramic particle coating layer on the surface of a negative electrode using a cross-linkable (thermosetting) binder to enhance the thermal stability of the anode. The cross-linkable (thermosetting) binder is cross-linked under the curing process and provides a robust ceramic layer on the surface of the negative electrode. Typically, the thermosetting ceramic layer is in the presence of a free radical initiator (e.g., peroxide (BPO, AIBN, phosphorus compounds or sulfates, etc.)) via a heat beam, ultraviolet beam or electron beam.

[0007] On the other hand, the additional ceramic particle layer coating the negative electrode surface can protect the SEI layer, mitigate lithium deposition and hinder dendrite growth (higher tortuosity), improve anode electrolyte wetting for uniform current density. Moreover, it provides a thermally conductive layer that can dissipate the isolated heat created from hot spots by soft or hard shorts. These benefits are effective only when the melting point of the binder in the ceramic layer is within the range that prevents thermal runaway.

[0008] The foregoing summary is illustrative only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] For a further understanding of the nature, objects and advantages of the present disclosure, reference should be made to the following detailed description, read in conjunction with the following drawings, in which like reference numerals represent like elements, and in which:

[0010] Figure 1A . is a schematic cross-section of a negative electrode including negative active electrode material on a single side of a current collector.

[0011] Figure 1B . is a schematic cross-section of a negative electrode including negative active electrode material on both sides of a current collector.

[0012] Figure 2 . is included Figure 1A Schematic cross section of a battery cell with a negative electrode.

[0013] Figure 3 . is included Figure 2 Schematic cross section of a battery pack with battery cells. DETAILED DESCRIPTION

[0014] Reference will now be made in detail to the currently preferred compositions, embodiments and methods of the present invention, which constitute the best mode of practicing the present invention currently known to the inventors. The accompanying drawings are not necessarily drawn to scale. However, it should be understood that the disclosed embodiments are merely examples of the present invention that can be embodied in various forms and alternative forms. Therefore, the specific details disclosed herein are not to be construed as limiting, but only as a representative basis for any aspect of the present invention and / or for teaching those skilled in the art to adopt the present invention in various ways.

[0015] Unless in the examples or where otherwise expressly indicated, all numerical quantities in this specification indicating amounts of materials or conditions of reaction and / or use should be understood as modified by the word "about" to describe the broadest scope of the invention. Practice within the stated numerical limits is generally preferred. Furthermore, unless expressly stated to the contrary: when a given chemical structure includes a substituent on a chemical moiety (e.g., on an aryl, alkyl, etc.), the substituent is attributed to the more general chemical structure of the given structure; otherwise, percentages, "parts," and ratio values ​​are by weight; the term "polymer" includes "oligomers," "copolymers," "terpolymers," and the like; molecular weights provided for any polymer refer to weight average molecular weights unless otherwise indicated; description of a group or class of materials as suitable or preferred for a given purpose in conjunction with the present invention implies that mixtures of any two or more of the members of the group or class are equally suitable or preferred; description of ingredients in chemical terms refers to the ingredients when added to any combination specified in the specification, and does not necessarily exclude chemical interactions between the ingredients of the mixture once mixed; the first definition of an acronym or other abbreviation applies to all subsequent uses of the same abbreviation herein and applies mutatis mutandis to normal grammatical variations of the initially defined abbreviation; and, unless expressly stated to the contrary, measurements of properties are determined by the same techniques as previously or later mentioned for the same property.

[0016] It must also be noted that, as used in the specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. For example, reference to a component in the singular is intended to include a plurality of components.

[0017] As used herein, the term "about" means that the amount or value in question can be the specified specific value or some other value in its neighborhood. Typically, the term "about" indicating a value is intended to indicate a range within + / - 5% of the value. As an example, the phrase "about 100" indicates a range of 100+ / - 5, i.e., a range of 95 to 105. Typically, when the term "about" is used, it is expected that similar results or effects according to the present invention can be obtained within a range of + / - 5% of the indicated value.

[0018] As used herein, the term "and / or" means that all or only one of the elements of the group may be present. For example, "A and / or B" should mean "only A or only B, or both A and B". In the case of "only A", the term also covers the possibility that B is not present, that is, "only A, but not B".

[0019] It should also be understood that the present invention is not limited to the specific embodiments and methods described below, as specific components and / or conditions may vary of course. In addition, the terminology used herein is only used to describe the purpose of specific embodiments of the present invention, and is not intended to be limiting in any way.

[0020] The term "comprising" is synonymous with "including," "having," "containing," or "characterized by." These terms are inclusive and open-ended and do not exclude additional, unrecited elements or method steps.

[0021] The phrase "consisting of" excludes any element, step, or ingredient not specified in the claim. When the phrase appears in a clause in the body of a claim, rather than immediately following the preamble, it limits only the elements set forth in that clause; the entire claim does not exclude other elements.

[0022] The phrase "consisting essentially of" limits the scope of a claim to the specified materials or steps, plus those that do not materially affect the basic and novel characteristics of the claimed subject matter.

[0023] The phrase “composed of” means “including” or “comprising.” Typically, the phrase is used to indicate that an object is formed from one material.

[0024] With respect to the terms "comprising," "consisting of," and "consisting essentially of," where one of these three terms is used herein, the presently disclosed and claimed subject matter may include the use of either of the other two terms.

[0025] The term "one or more" means "at least one", and the term "at least one" means "one or more". The terms "one or more" and "at least one" include "plurality" and "multiple" as subsets. In a refinement, "one or more" includes "two or more".

[0026] The terms "substantially," "generally," or "about" may be used herein to describe the disclosed or claimed embodiments. The term "substantially" may modify a value or relative property disclosed or claimed in the present disclosure. In such instances, "substantially" may mean that the value or relative property it modifies is within ±0%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, or 10% of the value or relative property.

[0027] It should also be understood that integer ranges explicitly include all intermediate integers. For example, integer ranges 1 to 10 explicitly include 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Similarly, ranges 1 to 100 include 1, 2, 3, 4, ..., 97, 98, 99, 100. Similarly, when any range is desired, intermediate values ​​that are increments of the difference between the upper and lower limits divided by 10 may be considered as alternative upper or lower limits. For example, if the range is 1.1 to 2.1, the following values ​​1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0 may be selected as lower or upper limits.

[0028] When referring to a numerical quantity, in one refinement, the term "less than" includes a non-inclusive lower limit that is 5% of the number indicated after "less than." For example, in one refinement, "less than 20" includes a non-inclusive lower limit of 1. Thus, this refinement of "less than 20" includes a range between 1 and 20. In another refinement, the term "less than" includes a non-inclusive lower limit that is, in ascending order of priority, 20%, 10%, 5%, or 1% of the number indicated after "less than."

[0029] "Thermosetting polymer" refers to a type of polymer that undergoes a chemical reaction during its curing process to produce a cross-linked three-dimensional network structure.

[0030] The term "residue" means a portion, and typically a major portion, of a molecular entity (such as a molecule) or a portion of a molecule (such as a group) that has undergone a chemical reaction and is now covalently attached to another molecular entity. In a refinement, the term "residue" when used with reference to a monomer or monomeric unit means the remaining portion of a monomeric unit after the monomeric unit has been incorporated into a polymer structure (such as a binder).

[0031] refer to Figure 1A and Figure 1B, a schematic diagram of a negative electrode including a negative electrode active material coated with a ceramic particle-containing layer is provided. The negative electrode 10 includes a negative electrode active layer 12, the negative electrode active layer including a negative electrode active material disposed above a negative electrode current collector 14 and generally in contact with the negative electrode current collector. Typically, the negative electrode current collector 14 is a metal plate or metal foil composed of a metal such as aluminum, copper, platinum, zinc, titanium, etc. Currently, copper is most commonly used for negative electrode current collectors. The ceramic particle-containing layer 16 is disposed above the negative electrode active layer 12 and generally in contact with the negative electrode active layer. Characteristically, the ceramic particle-containing layer 16 is composed of ceramic particles 18 and a thermosetting binder 19. The thermosetting binder is generally composed of residues of a crosslinkable monomer (e.g., a crosslinkable monomer that forms a crosslinked bond during cell processing). In a variation, the ceramic particle-containing layer 16 has a thickness of about 0.1 microns to about 30 microns. In an improved embodiment, the ceramic particle-containing layer 16 has a thickness of about 0.3 microns to about 10 microns. Examples of ceramic particles include, but are not limited to, barium titanate (i.e., BaTiO 3 ), aluminum oxide, boehmite, zirconium oxide, magnesium oxide, boron nitride, silicon carbide, titanium dioxide, silicon dioxide and combinations thereof. Typically, the ceramic particles have an average particle size of about 0.1 microns and 10 microns. In an improved embodiment, the ceramic particles have an average particle size of about 0.2 microns to 2 microns.

[0032] In a variation, the ceramic particles are present in an amount of about 80 wt % to about 99.9 wt % of the combined weight of the ceramic particles and the thermosetting binder. In a refinement, the thermosetting binder is present in an amount of about 0.1 wt % to about 20 wt % of the combined weight of the ceramic particles.

[0033] In a modification, the crosslinkable monomer includes a multifunctional part. In an improvement, the thermosetting binder is composed of a component selected from the group consisting of acrylic polymers, vinyl polymers, epoxy polymers, polyurethanes, fluoropolymers, polyesters, polyimides and combinations thereof. Additional examples of thermosetting binders include, but are not limited to, phenolic resins, polyurethanes, unsaturated polyester resins, melamine formaldehyde resins, silicone resins and combinations thereof. Epoxy resins are formed by the reaction of epoxy monomers with curing agents or hardeners, which results in a chemical crosslinking process called polymerization. Examples of epoxy monomers include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and novolac epoxy resins. Examples of curing agents include aliphatic amines (e.g., triethylenetetramine, diethylenetriamine) and aromatic amines (e.g., m-phenylenediamine), polyamides (e.g., the reaction product of polymerized fatty acids and polyamines), anhydrides (e.g., methylhexahydrophthalic anhydride and methylhexahydrophthalic anhydride), phenolic curing agents (e.g., phenolic resins), etc. Polyurethane is a thermosetting polymer formed by the reaction product of a polyol and an isocyanate. Examples of isocyanates include toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, etc. Examples of polyols include polyester polyols, polyether polyols, polycaprolactone polyols, acrylic polyols, etc. Unsaturated polyester resins are formed by the reaction of unsaturated dibasic acids or anhydrides with diols or polyols. Melamine formaldehyde resin is a thermosetting polymer formed by the condensation reaction of melamine and formaldehyde. Silicone resin is a thermosetting polymer formed by the hydrolysis and condensation of organosilanes and / or organosiloxanes.

[0034] In a variation, there is provided a method for producing Figure 1A and Figure 1B A method for forming a negative electrode 10. The method includes the step of preparing a negative electrode active material composition by mixing a negative electrode active material, a binder and a solvent. The negative electrode current collector 14 is coated with the negative electrode active material composition to form an uncured negative electrode active layer. The uncured negative electrode active layer is cured and / or dried to form a cured negative electrode active layer. A reactive mixture including ceramic particles and a crosslinkable monomer is formed. The cured negative electrode active layer is coated with the reactive mixture to form a thermosetting ceramic layer. The thermosetting ceramic layer is cured to form a layer containing ceramic particles. In an improved embodiment, the reactive mixture also includes a free radical initiator. The thermosetting ceramic layer can be thermally cured by UV light or with an electron beam. Examples of free radical initiators include, but are not limited to, peroxides (BPO, AIBN, etc.), phosphorus compounds or sulfates. Additional details of the composition and formation of the negative electrode active layer 12 and the negative electrode current collector 14 are described below.

[0035] refer to Figure 2, a schematic diagram of a rechargeable lithium-ion battery cell incorporating the negative electrode of FIG. 1 is provided. The battery cell 20 includes a negative electrode 10 as described above, a positive electrode 22, and a separator 24 interposed between the negative electrode and the positive electrode. The positive electrode 22 includes a positive electrode collector 26 and a positive electrode active material 28 disposed above and generally in contact with the positive electrode collector. Typically, the positive electrode collector 26 is a metal plate or foil composed of a metal such as aluminum, copper, platinum, zinc, titanium, etc. At present, aluminum is most commonly used for the positive electrode collector. The battery cell is immersed in an electrolyte 30 enclosed by a battery cell housing 32. The electrolyte 30 is absorbed into the separator 24. In other words, the separator 24 includes an electrolyte, thereby allowing lithium ions to move between the positive electrode and the negative electrode. The electrolyte includes a non-aqueous organic solvent and a lithium salt. The non-aqueous organic solvent is used as a medium for transmitting ions participating in the electrochemical reaction of the battery. Advantageously, the battery cell 20 may have a specific capacity greater than 150 mAh / g. In a further development, the battery cell 20 has a specific capacity of more than 190 mAh / g and typically less than 250 mAh / g.

[0036] refer to Figure 3 , providing a negative electrode incorporating FIG. 1 and Figure 2 A schematic diagram of a rechargeable lithium-ion battery having a battery cell of Figure 2 Typically, the rechargeable lithium-ion battery 40 includes Figure 2 At least one battery cell 20 of the design i . Each lithium-ion battery cell 20 i The invention comprises: a negative electrode 10, the negative electrode comprising a compound represented by Formula 1; a positive electrode 22, the positive electrode comprising a positive active material; and an electrolyte 30, wherein i is an integer mark for each battery cell. The mark i is from 1 to nmax, wherein nmax is the total number of battery cells in the rechargeable lithium ion battery 40. The electrolyte 30 comprises a non-aqueous organic solvent and a lithium salt. The non-aqueous organic solvent is used as a medium for transporting ions participating in the electrochemical reaction of the battery. A plurality of battery cells may be connected in series, in parallel and / or in combination thereof. A voltage output from the battery 40 is provided across terminals 42 and 44. Advantageously, the rechargeable lithium ion battery 40 may have a specific capacity greater than 150 mAh / g for each battery cell therein.

[0037] refer to Figure 2 and Figure 3 , the separator 24 physically separates the positive electrode 22 from the negative electrode 10, thereby presenting a short circuit, while allowing lithium ion transport for charging and discharging. Therefore, the separator 24 can be composed of any material suitable for this purpose. Examples of suitable materials that can constitute the separator 24 include, but are not limited to, polytetrafluoroethylene (e.g., ), fiberglass, polyester, polyethylene, polypropylene and combinations thereof. The separator 24 may be in the form of a woven fabric or a nonwoven fabric. The separator 24 may be in the form of a nonwoven fabric or a woven fabric. For example, polyolefin-based polymer separators (such as polyethylene and / or polypropylene) are commonly used in lithium-ion batteries. In order to ensure heat resistance or mechanical strength, a coated separator including a ceramic or polymer material coating may be used.

[0038] refer to Figure 2 and Figure 3 , the electrolyte 30 includes a lithium salt dissolved in a non-aqueous organic solvent. Therefore, the electrolyte 30 includes lithium ions that can be intercalated into the negative electrode active material during charging and into the anode active material during discharging. Examples of lithium salts include, but are not limited to, LiPF 6 , LiBF 4 、LiSbF 6 、LiAsF 6 ,LiC 4 F 9 SO 3 、LiClO 4 、LiAlO 2 、LiAlCl 4 、LiCl、LiI、LiB(C 2 O4) 2 In a refinement, the electrolyte includes a lithium salt in an amount of about 0.1 M to about 2.0 M.

[0039] Still reference Figure 2 and Figure 3 , the electrolyte includes a non-aqueous organic solvent and a lithium salt. Advantageously, the non-aqueous organic solvent is used as a medium for transporting ions and in particular lithium ions participating in the electrochemical reaction of the battery. Suitable non-aqueous organic solvents include carbonate-based solvents, ester-based solvents, ether-based solvents, ketone-based solvents, alcohol-based solvents, aprotic solvents and combinations thereof. Examples of carbonate-based solvents include, but are not limited to, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, methylethyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate and combinations thereof. Examples of ester-based solvents include, but are not limited to, methyl acetate, ethyl acetate, n-propyl acetate, methyl propionate, ethyl propionate, γ-butyrolactone, decanolactone, valerolactone, mevalonolactone, caprolactone and combinations thereof. Examples of ether-based solvents include, but are not limited to, dibutyl ether, tetraethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dimethoxyethane, 2-methyltetrahydrofuran, tetrahydrofuran, etc., and ketone-based solvents may include cyclohexanone, etc. Examples of alcohol-based solvents include, but are not limited to, methanol, ethanol, n-propanol, isopropanol, etc. Examples of aprotic solvents include, but are not limited to, nitriles such as R-CN (wherein R is C 2-20Straight chain, branched or cyclic hydrocarbons, which may include double bonds, aromatic rings or ether bonds), amides such as dimethylformamide, dioxolanes such as 1,3-dioxolane, sulfolane, etc. Advantageously, non-aqueous organic solvents can be used alone. In other variations, mixtures of non-aqueous organic solvents can be used. Such mixtures are generally formulated to optimize battery performance. In one improvement, carbonate-based solvents are prepared by mixing cyclic carbonates and linear carbonates. In variations, the electrolyte 30 may also include vinylene carbonate-based or ethylene carbonate-based compounds to extend the battery cycle life.

[0040] Refer to Figure 1. Figure 2 and Figure 3 , the positive electrode and the negative electrode can be made by methods known to those skilled in the art of lithium-ion batteries. Typically, an active material (e.g., a negative electrode or a positive electrode active material) is mixed with a conductive material and a binder in a solvent (e.g., N-methylpyrrolidone) to form an active material composition and the composition is coated on a current collector. Electrode manufacturing methods are well known and therefore are not described in detail in this specification. The solvent includes N-methylpyrrolidone and the like, but is not limited thereto.

[0041] Refer to Figure 1. Figure 2 and Figure 3 , the positive electrode active layer 28 includes a positive electrode active material, a binder and an optional conductive material. The binder can increase the bonding properties of the positive electrode active material particles to each other and to the positive electrode current collector 26. Examples of suitable binders include, but are not limited to, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers containing ethylene oxide, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene butadiene rubber, acrylate styrene butadiene rubber, epoxy resin, nylon, etc., and combinations thereof. The conductive material provides conductivity to the positive electrode 10. Examples of suitable conductive materials include, but are not limited to, natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber, copper, metal powder, metal fiber, and combinations thereof. Examples of metal powders and metal fibers include nickel, aluminum, silver, and the like.

[0042] Refer to Figure 1. Figure 2 and Figure 3, the negative electrode active layer 12 includes a negative electrode active material, including a binder, and optionally includes a conductive material. The negative electrode active materials used herein may be those known to those skilled in the art of lithium ion batteries. Negative electrode active materials include, but are not limited to, carbon-based negative electrode active materials, silicon-based negative electrode active materials, and combinations thereof. Suitable carbon-based negative electrode active materials may include graphite and graphene. Suitable silicon-based negative electrode active materials may include at least one selected from silicon, silicon oxide, silicon oxide coated with conductive carbon on the surface, and silicon (Si) coated with conductive carbon on the surface. For example, silicon oxide may be of the formula SiO z Description, wherein z is 0.09 to 1.1. A mixture of a carbon-based negative electrode active material and a silicon-based negative electrode active material can also be used for the negative electrode active material.

[0043] The negative electrode binder increases the bonding properties of the negative electrode active material particles to each other and to the current collector. The binder may be a non-aqueous binder, an aqueous binder, or a combination thereof. Examples of non-aqueous binders may be polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers containing ethylene oxide, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamide-imide, polyimide, or a combination thereof. The aqueous binder may be a rubber-based binder or a polymer resin binder. Examples of rubber-based binders include, but are not limited to, styrene-butadiene rubber, acrylated styrene-butadiene rubber, acrylonitrile-butadiene rubber, acrylic rubber, butyl rubber, fluororubber, and combinations thereof. Examples of polymer resin binders include, but are not limited to, polyethylene, polypropylene, ethylene-propylene copolymer, polyethylene oxide, polyvinyl pyrrolidone, epichlorohydrin, polyphosphazene, polyacrylonitrile, polystyrene, ethylene-propylene-diene copolymer, polyvinyl pyridine, chlorosulfonated polyethylene, latex, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, and combinations thereof.

[0044] Although exemplary embodiments are described above, these embodiments are not intended to describe all possible forms of the present invention. Rather, the words used in the specification are descriptive rather than restrictive terms, and it should be understood that various changes may be made without departing from the spirit and scope of the present invention. In addition, the features of the various embodiments of implementation may be combined to form other embodiments of the present invention.

[0045] According to the present invention, a negative electrode for a rechargeable lithium-ion battery is provided, which comprises: a negative electrode collector; a negative electrode active layer, wherein the negative electrode active layer is arranged above the negative electrode collector, and the negative electrode active layer is composed of a negative electrode active material; and a ceramic particle-containing layer, wherein the ceramic particle-containing layer is arranged above the negative electrode active layer, and the ceramic particle-containing layer is composed of ceramic particles and a thermosetting binder, and the thermosetting binder is composed of residues of a cross-linkable monomer.

[0046] According to an embodiment, the cross-linkable monomer comprises a multifunctional moiety.

[0047] According to an embodiment, the thermosetting binder is composed of a component selected from the group consisting of acrylic polymers, vinyl polymers, epoxy polymers, polyurethanes, fluoropolymers, polyesters, polyimides, epoxy resins, phenolic resins, polyurethanes, unsaturated polyester resins, melamine formaldehyde resins, silicone resins, and combinations thereof.

[0048] According to an embodiment, the ceramic particle-containing layer has a thickness of about 0.1 micrometers to about 30 micrometers.

[0049] According to an embodiment, the ceramic particle-containing layer has a thickness of about 0.3 micrometers to about 10 micrometers.

[0050] According to an embodiment, the ceramic particles include particles selected from the group consisting of barium titanate, aluminum oxide, boehmite, zirconium oxide, magnesium oxide, boron nitride, silicon carbide, titanium dioxide, silicon dioxide, and combinations thereof.

[0051] According to an embodiment, the ceramic particles have an average particle size of about 0.1 micrometers and 10 micrometers.

[0052] According to an embodiment, the ceramic particles have an average particle size of about 0.2 microns to 2 microns.

[0053] According to an embodiment, the ceramic particles are present in an amount of about 80 wt % to about 99.9 wt % of the combined weight of the ceramic particles and the thermosetting binder, and the thermosetting binder is present in an amount of about 0.1 wt % to about 20 wt % of the combined weight of the ceramic particles.

[0054] According to an embodiment, the negative electrode active material is a carbon-based negative electrode active material, a silicon-based negative electrode active material or a combination thereof.

[0055] According to the present invention, a rechargeable lithium-ion battery having at least one lithium-ion battery cell is provided, each lithium-ion battery cell comprising: a negative electrode, the negative electrode comprising: a negative electrode collector; a negative electrode active layer, the negative electrode active layer being arranged above the negative electrode collector, the negative electrode active layer being composed of a negative electrode active material; and a ceramic particle-containing layer, the ceramic particle-containing layer being arranged above the negative electrode active layer, the ceramic particle-containing layer being composed of ceramic particles and a thermosetting binder, the thermosetting binder being composed of residues of a cross-linkable monomer; a positive electrode, the positive electrode comprising a positive electrode active material; and an electrolyte, the electrolyte contacting the negative electrode and the positive electrode.

[0056] According to an embodiment, each lithium-ion battery cell further includes a separator interposed between the negative electrode and the positive electrode.

[0057] According to an embodiment, the thermosetting binder is composed of a component selected from the group consisting of acrylic polymers, vinyl polymers, epoxy polymers, polyurethanes, fluoropolymers, polyesters, polyimides, and combinations thereof.

[0058] According to an embodiment, the ceramic particle-containing layer has a thickness of about 0.1 micrometers to about 30 micrometers.

[0059] According to an embodiment, the ceramic particles include BaTiO 3 , alumina, boehmite, zirconia, magnesia, boron nitride, silicon carbide, titanium dioxide, silicon dioxide and combinations thereof.

[0060] According to an embodiment, the ceramic particles have an average particle size of about 0.1 micrometers and 10 micrometers.

[0061] According to an embodiment, the ceramic particles have an average particle size of about 0.2 microns to 2 microns.

[0062] According to an embodiment, the ceramic particles are present in an amount of about 0.1 wt % to about 20 wt % of the combined weight of the ceramic particles and the thermosetting binder, and the thermosetting binder is present in an amount of about 99.9 wt % to about 80 wt % of the combined weight of the ceramic particles.

[0063] According to the present invention, a method for making a negative electrode includes: preparing a negative electrode active material composition by mixing a negative electrode active material, a binder and a solvent; coating a negative electrode current collector with the negative electrode active material composition to form an uncured negative electrode active layer; curing and / or drying the uncured negative electrode active layer to form a cured negative electrode active layer; forming a reactive mixture including ceramic particles and a cross-linkable monomer; coating the cured negative electrode active layer with the reactive mixture to form a thermosetting ceramic layer; and curing the thermosetting ceramic layer to form a ceramic particle-containing layer.

[0064] In one aspect of the invention, the reactive mixture further comprises a free radical initiator.

Claims

1. A negative electrode for a rechargeable lithium-ion battery, the negative electrode comprising: negative electrode current collector; A negative electrode active layer, the negative electrode active layer is disposed above the negative electrode current collector, the negative electrode active layer is composed of a negative electrode active material; as well as The ceramic particle-containing layer is disposed above the negative electrode active layer, the ceramic particle-containing layer is composed of ceramic particles and a thermosetting binder, and the thermosetting binder is composed of residues of a cross-linkable monomer.

2. The negative electrode of claim 1, wherein the crosslinkable monomer comprises a multifunctional moiety.

3. The negative electrode of claim 1, wherein the thermosetting binder is composed of a component selected from the group consisting of acrylic polymers, vinyl polymers, epoxy polymers, polyurethanes, fluoropolymers, polyesters, polyimides, epoxy resins, phenolic resins, polyurethanes, unsaturated polyester resins, melamine formaldehyde resins, silicone resins, and combinations thereof.

4. The negative electrode of claim 1, wherein the ceramic particle-containing layer has a thickness of about 0.1 micrometers to about 30 micrometers.

5. The negative electrode of claim 1, wherein the ceramic particle-containing layer has a thickness of about 0.3 microns to about 10 microns.

6. The negative electrode of claim 1, wherein the ceramic particles comprise particles selected from the group consisting of barium titanate, aluminum oxide, boehmite, zirconium oxide, magnesium oxide, boron nitride, silicon carbide, titanium dioxide, silicon dioxide, and combinations thereof.

7. The negative electrode of claim 1, wherein the ceramic particles have an average particle size of about 0.1 microns and 10 microns.

8. The negative electrode of claim 1, wherein the ceramic particles have an average particle size of about 0.2 microns to 2 microns.

9. The negative electrode of claim 1, wherein the ceramic particles are present in an amount of about 80 wt % to about 99.9 wt % of the combined weight of the ceramic particles and the thermosetting binder, and the thermosetting binder is present in an amount of about 0.1 wt % to about 20 wt % of the combined weight of the ceramic particles. 10 . The negative electrode of claim 1 , wherein the negative electrode active material is a carbon-based negative electrode active material, a silicon-based negative electrode active material, or a combination thereof.

11. A rechargeable lithium ion battery comprising at least one lithium ion battery cell, each lithium ion battery cell comprising: A negative electrode, the negative electrode comprising: negative electrode current collector; a negative electrode active layer, the negative electrode active layer being disposed above the negative electrode current collector, the negative electrode active layer being composed of a negative electrode active material; and A ceramic particle-containing layer, the ceramic particle-containing layer is disposed above the negative electrode active layer, the ceramic particle-containing layer is composed of ceramic particles and a thermosetting binder, and the thermosetting binder is composed of residues of a cross-linkable monomer; a positive electrode comprising a positive electrode active material; and An electrolyte contacts the negative electrode and the positive electrode.

12. The rechargeable lithium ion battery of claim 11, wherein each lithium ion battery cell further comprises a separator interposed between the negative electrode and the positive electrode.

13. The rechargeable lithium ion battery of claim 11, wherein the thermosetting binder is composed of a component selected from the group consisting of acrylic polymers, vinyl polymers, epoxy polymers, polyurethanes, fluoropolymers, polyesters, polyimides, and combinations thereof.

14. The rechargeable lithium ion battery of claim 11, wherein the ceramic particle-containing layer has a thickness of about 0.1 micrometers to about 30 micrometers.

15. The rechargeable lithium ion battery of claim 11, wherein the ceramic particles comprise particles selected from the group consisting of BaTiO3, alumina, boehmite, zirconium oxide, magnesium oxide, boron nitride, silicon carbide, titanium dioxide, silicon dioxide, and combinations thereof.

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