Battery material, preparation method thereof, and battery

Abstract

To provide a battery material having high coulombic efficiency and excellent electrochemical performance.SOLUTION: A battery material, a preparation method thereof, and a battery are provided. The material includes: an active material configured to undergo a chemical reaction during battery charging and / or discharging; and one or more metal atoms configured to retain one or more oxygen atoms of the active material and to passivate the one or more oxygen atoms of the active material during the battery charging and / or discharging.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a battery material, a method for preparing the same, and a battery. [Background technology]

[0002] The conventional structure and shape of electrodes for certain rechargeable batteries involves coating an active material on an aluminum foil to form the positive electrode and a copper foil to form the negative electrode. To achieve higher battery energy density, the use of high-capacity negative electrode materials (e.g., silicon) is required. During the lithiation process, lithium and silicon form a lithium-silicon alloy, which causes a volume expansion of up to 400%, leading to the rupture and degradation of the electrode structure. This constitutes one of the main barriers to improving the energy density of certain rechargeable batteries (e.g., lithium-ion batteries).

[0003] Lithium-ion batteries (LIBs) are used in many portable electronic devices, power tools, electric vehicles, and internal combustion engine vehicles. LIBs typically consist of a lithium-containing positive electrode material and a lithium-accepting negative electrode material. During charging, lithium migrates from the positive electrode to the negative electrode. During discharging, some of the lithium is returned to the positive electrode. Coulombic efficiency is defined as the ratio of lithium ions released per cycle during discharging to the lithium ions transferred to the negative electrode during charging.

[0004] Until now, LIBs have been the main choice for renewable energy battery applications, requiring large-scale energy storage systems. However, many of the materials used in conventional LIBs have low storage capacities, allowing only small amounts of energy to be stored per charge, resulting in poor battery performance.

[0005] CN105399100A discloses a method for preparing nanoporous silicon by alloying silicon powder and magnesium powder to prepare a precursor MgSi / Mg composite, and then pickling the resulting product to dealloy it. However, water molecules inevitably react with elemental silicon during the pickling process, irreversibly oxidizing it. This silicon oxide generates irreversible products with lithium ions during charging, negatively impacting coulomb efficiency.

[0006] CN114597375A proposes a method for reducing silicon oxide with highly inert metal elements (e.g., silver, copper, nickel, iron, and cobalt) to reduce the oxidation level of silicon element and improve the coulomb efficiency of silicon element, which is the anode. However, these inert metals (e.g., silver) are expensive, which is a disadvantage for mass production and commercialization of silicon element, which is the anode material.

[0007] CN115053364A discloses a method for improving the coulombic efficiency by adding zirconium metal to elemental silicon, but this method only improves the coulombic efficiency by 2%, which is not very effective.

[0008] The methods disclosed in the above three patent publications that use various inert metal elements to reduce porous silicon element or nanosilicon element have practical problems, and it is difficult to substantially improve the coulomb efficiency of silicon element. Summary of the Invention

[0009] In view of the problems of the prior art, one object of the present invention is to provide a material for a battery having high coulombic efficiency and excellent electrochemical performance. Another object of the present invention is to provide a battery including the material. Another object of the present invention is to provide a method for preparing the material.

[0010] According to one aspect of the present invention, the present invention provides a method for manufacturing a cellular membrane comprising: an active material arranged to undergo a chemical reaction during charging and / or discharging of the battery; and one or more metal atoms arranged to retain and passivate one or more oxygen atoms of the active material during charging and / or discharging of the battery; The present invention provides a battery material comprising:

[0011] According to the material of the present invention, preferably, said metal atom forms a complex with said active material.

[0012] According to the material of the present invention, preferably the metal atoms are bound to oxygen atoms on the surface of the active material within the complex.

[0013] According to the material of the present invention, the metal atoms are preferably bound to oxygen atoms on the surface of the active material by covalent bonds.

[0014] In accordance with the material of the present invention, preferably the metal atoms remain bonded to the oxygen atoms during charging and / or discharging of the battery.

[0015] According to the material of the present invention, preferably, the metal atoms react with the oxygen atoms to form an oxide within the complex.

[0016] According to the material of the present invention, preferably, said oxide forms at least one of an amorphous material and a polycrystalline material.

[0017] In the material according to the present invention, the metal atoms preferably hold the oxygen atoms and inactivate the oxygen atoms, thereby improving the coulomb efficiency of the material.

[0018] According to the material of the present invention, the metal atom is preferably one or more selected from Na, K, Rb, Cs, Ca, Al, Mg, Sr, Sc, Y, Zr, Ti, La, Ce and Hf.

[0019] According to the material of the present invention, preferably, the metal atoms are embedded in the active material so as to hold the oxygen atoms and deactivate the oxygen atoms.

[0020] According to the material of the present invention, preferably, the metal atoms are embedded in the active material as at least one of a metal simple substance, a metal oxide, a metal hydroxide, a metal acetate, a metal nitrate, a metal sulfate, and a metal carbonate.

[0021] According to the material of the present invention, preferably, the active material is one or more selected from a semi-metal element, an oxide of a semi-metal element, a metal element, and an oxide of a metal element.

[0022] According to the material of the present invention, preferably, the semi-metal element is Si and / or B.

[0023] According to the material of the present invention, preferably, the active material is Si, and contains at least one of SiO x (where 0 < x < 2) and SiO2.

[0024] According to the material of the present invention, preferably, the active material is in a particulate form, and the particle size of the active material is 5 nm to 5 mm.

[0025] According to the material of the present invention, preferably, the active material is used as a negative electrode material in the battery.

[0026] According to another aspect of the present invention, the present invention provides a battery including a positive electrode, a negative electrode, and an electrolyte, wherein the negative electrode is made of the above material, and the electrolyte is ionically connected between the negative electrode and the positive electrode.

[0027] According to the battery of the present invention, preferably, during the charging period of the battery, metal ions of the positive electrode move to the negative electrode, and during the discharging period of the battery, the metal ions return to the positive electrode.

[0028] In the battery according to the present invention, preferably, the metal ions are not trapped by oxygen atoms in the negative electrode during discharge of the battery.

[0029] In the battery according to the present invention, the metal ions are preferably one or more selected from Li, Na, K, Ca and Mg.

[0030] According to another aspect of the present invention, there is provided a method for producing a medicament for the treatment of a pulmonary arthritis, comprising: preloading an active material with one or more metal atoms, the active material being configured to undergo a chemical reaction during charging and / or discharging of the battery, the metal atoms being configured to retain one or more oxygen atoms on the surface of the active material and passivate one or more oxygen atoms on the surface of the active material during charging and / or discharging of the battery; A method for preparing the battery material, comprising:

[0031] According to the method of the present invention, preferably, one or more types of metal atoms are preloaded into the active material by annealing the active material and the material containing the metal atoms in an atmosphere of at least one selected from helium gas, nitrogen gas, and argon gas at an annealing temperature of 500°C to 1200°C.

[0032] According to the method of the present invention, preferably, increasing the annealing temperature increases the coulombic efficiency of the cell.

[0033] According to the method of the present invention, preferably, the active material and the material containing metal atoms are preloaded with the metal atoms by processing the active material and the material containing metal atoms in a high-energy ball mill, mixing the active material and the material containing metal atoms, and then heat-treating the mixture in an atmosphere of at least one selected from helium gas, nitrogen gas, and argon gas. [Brief explanation of the drawings]

[0034] [Figure 1] FIG. 2 is an SEM image of the porous silicon particles obtained in Example 1. [Figure 2] FIG. 2 is a pore size distribution diagram of the porous silicon particles obtained in Example 1. [Figure 3] FIG. 2 is an X-ray diffraction pattern of the battery material obtained in Example 1. [Figure 4] FIG. 2 is an X-ray diffraction pattern of the battery material obtained in Example 2. [Figure 5] FIG. 1 is an X-ray diffraction pattern of the battery material obtained in Example 3. DETAILED DESCRIPTION OF THE INVENTION

[0035] Through research, testing, and experimentation, the present inventors have found that semi-metallic and semi-metallic oxides, such as silicon-based materials, have the potential to be high-capacity negative electrodes for lithium-ion batteries. However, high-surface-area semi-metallic (e.g., Si) particles are highly reactive and, after entering the crystal lattice upon charging, tend to dissolve in the semi-metallic (e.g., Li) oxides. x Si) reacts with the electrolyte and traps lithium within the material, reducing the overall reversibility of lithium insertion and desorption.

[0036] During the charging process, lithium ion (Li + ) reacts with Si to store lithium ions, and lithium ions are released during the discharge process. Ideally, the coulombic efficiency of the negative electrode is close to 100%, meaning that the amount of lithium ions reaching the negative electrode should be the same as the amount of lithium ions removed. If lithium ions are trapped in the negative electrode, the coulombic efficiency will be less than 100%. Since the usable capacity and energy density of the battery depend on the amount of reversible lithium ions, the usable capacity and energy density of the battery will be low.

[0037] The inventors have discovered that oxygen on the surface of the negative electrode material adversely affects the charge and discharge process. In particular, some oxygen deactivates silicon, thereby reducing the total amount of intercalated lithium and the storage capacity. During the lithiation process (i.e., the charging process), some oxygen reacts with lithium and forms irreversible products, among which Li is trapped, reducing the reversibility of Li ions, i.e., the initial coulombic efficiency of the material. Some oxygen gradually dissolves in the electrolyte, adversely affecting the coulombic efficiency of the material. Therefore, lithium is primarily trapped by oxygen within the crystal lattice, offsetting the advantage of higher capacity of the active material.

[0038] <Battery materials> Based on the above findings, the present invention provides a battery material comprising an active material arranged to undergo a chemical reaction during battery charging and / or discharging, and one or more metal atoms arranged to retain one or more oxygen atoms on the active material surface and to passivate one or more oxygen atoms on the active material surface during battery charging and / or discharging. The battery according to the present invention is preferably a lithium-ion battery. This prevents lithium from being trapped by oxygen in the crystal lattice, improving the coulombic efficiency of the material. The active material according to the present invention is used as a negative electrode material for the battery.

[0039] In the material of the present invention, the metal atom can form a complex with the active material, which is advantageous in improving the stability of the material. The active material has oxygen atoms on its surface. In the complex, the metal atom is bonded to the oxygen atoms on the surface of the active material. In some embodiments, the metal atom can be bonded to the oxygen atoms on the surface of the active material by a covalent bond. In some embodiments, the metal atom can be bonded to the oxygen atoms on the surface of the active material by a coordinate bond.

[0040] According to a preferred embodiment of the present invention, the metal atoms remain bonded to the oxygen atoms during charging and / or discharging of the battery. This effectively prevents or reduces lithium from being trapped by oxygen in the crystal lattice. The reaction between the metal atoms and the oxygen atoms can form an oxide within the complex. The oxide according to the present invention is formed as an amorphous material and / or a polycrystalline material. The metal atoms retain and passivate the oxygen atoms, thereby improving the coulombic efficiency of the material. Specifically, the metal atoms are embedded in the active material to retain and passivate the oxygen atoms.

[0041] In some embodiments, the active material has an oxide on its surface, which comprises the active material and oxygen atoms, and at least a portion of the oxygen atoms in the oxide are bonded to a metal element. Specifically, at least 50% of the oxygen atoms on the surface of the active material are bonded to a metal element, preferably at least 80% of the oxygen atoms on the surface of the active material are bonded to a metal element, and more preferably at least 90% of the oxygen atoms on the surface of the active material are bonded to a metal element. In some embodiments, all of the oxygen atoms on the surface of the active material are bonded to a metal element.

[0042] The mass ratio of the active material to the metal atoms may be 10:(0.2-5), preferably 10:(0.5-3), and more preferably 10:(0.8-2). In some embodiments, the mass ratio of the active material to the metal atoms is 10:(1-1.2). The mass of the metal atoms is calculated in terms of the mass of their oxides.

[0043] metal atom The metal atom according to the present invention is one or more selected from alkali metal elements, alkaline earth metal elements, Group IIIA elements, Group IIIB elements, and Group IVB elements. Specific examples of alkali metal elements include, but are not limited to, Na, K, Rb, and Cs. Preferably, the alkali metal element is K. Specific examples of alkaline earth metal elements include, but are not limited to, Ca, Mg, and Sr. Preferably, the alkaline earth metal element is Ca. Specific examples of Group IIIA elements include, but are not limited to, Al and Ga. Preferably, the Group IIIA element is Al. Specific examples of Group IIIB elements include, but are not limited to, Sc, Y, and lanthanides. Specific examples of lanthanides include, but are not limited to, La and Ce. Preferably, the Group IIIB element is Y. Specific examples of Group IVB elements include, but are not limited to, Ti and Zr. Preferably, the Group IVB element is Zr.

[0044] According to one embodiment of the present invention, the metal atoms are a combination of an alkaline earth metal element, an alkali metal element, and a Group IVB element. The mass ratio of the alkaline earth metal element, the alkali metal element, and the Group IVB element may be (0.1-1):(0.1-1):1, preferably (0.2-0.8):(0.2-0.8):1, and more preferably (0.3-0.6):(0.3-0.6):1. The mass of each of the elements is calculated in terms of the mass of its oxide.

[0045] According to another embodiment of the present invention, the metal atom is a group IIIB element.

[0046] According to another embodiment of the present invention, the metal element is a combination of a Group IIIA element and an alkali metal element. The mass ratio of the Group IIIA element to the alkali metal element may be (0.5-2):1, preferably (0.8-1.5):1, and more preferably (1-1.2):1. The mass of each element is calculated in terms of the mass of its oxide.

[0047] In the material according to the present invention, the metal atom is one or more selected from Na, K, Rb, Cs, Ca, Al, Mg, Sr, Sc, Y, Zr, Ti, La, Ce, and Hf. In some embodiments, the metal atom is one or more selected from Na, K, Rb, Cs, Ca, Al, Mg, Sr, Sc, Y, Zr, and Ti. In a preferred embodiment, the metal atom is one or more selected from K, Ca, Zr, Al, and Y. According to one embodiment of the present invention, the metal atom is a combination of K, Ca, and Zr. According to another embodiment of the present invention, the metal atom is Y. According to another embodiment of the present invention, the metal atom is a combination of K and Al. <> <>

[0048] <> In the material according to the present invention, the metal atom can be supplied from the metal itself or its compound. The compound of the metal atom may be one or more selected from metal oxides, metal hydroxides, metal acetates, metal nitrates, metal sulfates, and metal carbonates. Such substances can all adopt commercially available ones. In some embodiments, the metal atom is embedded in the active material as at least one of a metal, a metal oxide, a metal hydroxide, a metal acetate, a metal nitrate, a metal sulfate, and a metal carbonate. Preferably, it is embedded in the active material as the metal oxide. <> <><>

[0049] <><> <><> active material <><> In the material according to the present invention, the active material is preferably a semi-metal (Me)-based material. The active material may be one or more selected from a semi-metal element, an oxide of a semi-metal element, a metal element, and an oxide of a metal element. The semi-metal element is preferably Si and / or B. Specific examples of the semi-metal (Me)-based material include, but are not limited to, silicon-based materials and boron-based materials. In some embodiments, the active material is silicon and contains at least one of SiO<><><000> x (where 0 < x < 2) and SiO2. According to one embodiment of the present invention, the active material is SiO<><><000> xIt is a silicon-based material including (where 0 < x < 2). According to another embodiment of the present invention, the active material is a silicon-based material containing SiO2. According to another embodiment of the present invention, the active material is SiO x It is a silicon-based material including (where 0 < x < 2) and SiO2.

[0050] The active material according to the present invention is a silicon-based material, and preferably has at least one of SiO x (where 0 < x < 2) and SiO2 on the surface of the active material. According to one embodiment of the present invention, the active material is a silicon material having a pore structure inside and / or on the surface (hereinafter, also referred to as "porous silicon material").

[0051] In the material according to the present invention, the active material may be in a particulate form, and the particle diameter of the active material is 5 nm to 5 mm, preferably 500 nm to 50 μm, more preferably 1 to 30 μm, and most preferably 1 to 5 μm. The particle diameter can be measured by a conventional method. The present inventor has found that using a micron-sized active material is advantageous for improving the Coulomb efficiency of the material.

[0052] The silicon-based material according to the present invention may be porous silicon particles, for example, porous amorphous silicon particles and / or porous polycrystalline silicon particles. The particle diameter of the porous silicon particles according to the present invention is preferably 500 nm to 50 μm, more preferably 1 to 5 μm. By using micron-sized porous silicon particles, it is advantageous for improving the Coulomb efficiency of the material.

[0053] The porous silicon particles according to the present invention can be provided by a porous silicon material. The porous silicon material can be prepared by using an alloy reaction of magnesium metal and silicon metal and a dealloying method by vacuum distillation. Hereinafter, the preparation method of the porous silicon material and other related equipment and methods will be described.

[0054] The method for preparing a porous silicon material according to the present invention comprises the following steps:

[0055] (i) placing the alloy material and silicon particles into a furnace, evacuating the air in the furnace, and filling it with an inert gas; (ii) heating the alloy material and silicon particles to 1000-1300°C, keeping the temperature for 1-6 hours, and then removing and crushing the alloy after natural cooling; (iii) placing the crushed alloy in a vacuum furnace, discharging the gas from the furnace, heating the temperature to 700-950°C, and performing vacuum distillation to dealloy the alloy to obtain a porous silicon material; In step (i), the air in the furnace may be evacuated using an air pump. The pressure in the furnace corresponds to 0.01% atmospheric pressure. The alloying material may contain at least one of zinc, magnesium, calcium, strontium, barium, boron, phosphorus, lithium, and iron. The silicon content in the alloying material and the silicon particles is approximately 20 to 99 mol%. The mass ratio of the silicon particles to the alloying material may be 33:(40 to 90), preferably 33:(50 to 80), and more preferably 33:(60 to 70). The inert gas may be one or more selected from nitrogen gas, argon gas, helium gas, and neon gas. According to one embodiment of the present invention, the inert gas is argon gas.

[0056] In step (ii), the heating temperature is preferably 1100 to 1250° C., more preferably 1100 to 1150° C. The temperature retention time is preferably 2 to 5 hours, more preferably 2 to 3 hours.

[0057] In step (iii), all gas in the furnace is discharged using a molecular pump. For example, the pressure inside the furnace corresponds to 0.001% atmospheric pressure. The heating temperature is preferably 750 to 850°C, more preferably 800 to 830°C.

[0058] Hereinafter, the alloy material will be described using metallic magnesium.

[0059] (i) Metallic magnesium and silicon particles are placed in a furnace, the air inside the furnace is evacuated, and then argon gas is filled in as an inert protective atmosphere.

[0060] (ii) Magnesium and silicon particles are heated to 1000-1300°C, kept at that temperature for 1-6 hours, and then naturally cooled. After that, the magnesium silicon alloy is taken out and crushed.

[0061] (iii) The crushed magnesium silicon alloy is placed in a vacuum furnace, the gas inside the furnace is discharged, the temperature is heated to 700 to 950°C, and vacuum distillation is carried out to dealloy the alloy, thereby obtaining a porous silicon material.

[0062] The porous silicon material is polished to form porous silicon particles. Polishing may be performed using a ball mill. The mill balls used in the ball mill may be zirconia balls. The diameter of the mill balls may be 0.5 to 5 cm, preferably 1 to 3 cm. The ball to material ratio may be (3 to 9):1, preferably (4 to 8):1, and more preferably (5 to 7):1. The ball mill may be performed at a rotation speed of 200 to 700 rpm, preferably 300 to 500 rpm. The ball milling time may be 0.5 to 5 hours, preferably 1 to 3 hours, and more preferably 1.5 to 2 hours.

[0063] In some embodiments, the porous silicon material is placed in a zirconia ball mill jar, and zirconia balls are added at a weight ratio of 1:5-6 (material:balls). The mill is then polished at a rotation speed of 300-500 rpm for 1.5-2 hours to obtain porous silicon particles with a particle diameter of 1-5 μm.

[0064] In one broad aspect, the present invention provides a method for manufacturing a semiconductor device comprising: (i) an apparatus for alloying silicon particles with an alloying material to form an alloy; (ii) an apparatus for casting the alloy into an alloy sheet, strip or film; and (iii) an apparatus for extracting alloy material from the alloy sheet, strip or film to form a porous silicon material; The present invention provides an apparatus for preparing a porous silicon material from silicon particles comprising:

[0065] In another broad configuration, the present invention provides a method for manufacturing a semiconductor device comprising: (i) alloying at least one of a silicon source and an aluminum source with an alloying material to form an alloy; (ii) casting the alloy into an alloy sheet, strip or film; (iii) extracting the alloy sheet, strip or film to form at least one of a porous silicon sheet, strip or film and a porous aluminum sheet, strip or film; and (iv) interacting at least one of the porous silicon sheet, strip or film and the porous aluminum sheet, strip or film with an aqueous solution, and generating hydrogen gas upon said interaction; A method for preparing hydrogen gas, comprising:

[0066] In step (i), the alloy material may contain at least one of zinc, magnesium, calcium, strontium, barium, boron, phosphorus, lithium, and iron. Other impurities in the alloy do not significantly affect the performance of the prepared hydrogen gas. Step (i) can produce an alloy containing about 20 to 99 mol% silicon. Preferably, step (i) can produce an alloy containing about 60 mol% silicon.

[0067] In another broad aspect, the present invention provides a method for preparing at least one of a porous silicon sheet, strip, or film and a porous aluminum sheet, strip, or film for interaction with a solution containing HO to produce hydrogen gas, the method comprising the steps of: (i) alloying at least one of a silicon source and an aluminum source with an alloying material to form an alloy; (ii) casting the alloy into an alloy sheet, strip or film; and (iii) extracting the alloy sheet, strip or film to form at least one of the porous silicon sheet, strip or film and the porous aluminum sheet, strip or film; The present invention provides a method comprising:

[0068] The H2O-containing solution may be substantially basic.

[0069] In another broad configuration, the present invention provides a method for manufacturing a semiconductor device comprising: (i) alloying at least one of a silicon source and an aluminum source with an alloying material to form an alloy; (ii) casting the alloy into an alloy sheet, strip or film; (iii) extracting the alloy sheet, strip or film to form at least one of a porous silicon sheet, strip or film and a porous aluminum sheet, strip or film; and Step (iv) of interacting at least one of the porous silicon sheet, strip or film and the porous aluminum sheet, strip or film with an aqueous solution to produce hydrogen gas by said interaction, wherein the aqueous solution is preferably substantially basic; The present invention provides a method for preparing hydrogen gas comprising:

[0070] In another broad configuration, the present invention provides an apparatus for producing at least one of a porous silicon sheet, strip or film, and a porous aluminum sheet, strip or film, wherein the at least one of the porous silicon sheet, strip or film and the porous aluminum sheet, strip or film is arranged to produce hydrogen gas upon interaction with an aqueous solution, the apparatus comprising: An apparatus (i) for alloying at least one of a silicon raw material and an aluminum raw material with an alloy material to form an alloy; (ii) an apparatus for casting the alloy into an alloy sheet, strip or film; and (iii) an apparatus for extracting the alloy sheet, strip or film to form at least one of a porous silicon sheet, strip or film, and a porous aluminum sheet, strip or film; The facility provides facilities including:

[0071] In another broad aspect, the present invention provides an apparatus for preparing hydrogen gas, comprising an apparatus for interacting at least one of a porous silicon sheet, strip or film and a porous aluminum sheet, strip or film with an aqueous solution to produce hydrogen gas.

[0072] The present invention also provides (i) alloying at least one of a silicon source and an aluminum source with an alloying material to form an alloy; (ii) casting the alloy into an alloy sheet, strip or film; and (iii) extracting the alloy sheet, strip or film to form at least one of the porous silicon sheet, strip or film and the porous aluminum sheet, strip or film; At least one of a porous silicon sheet, strip or film and a porous aluminum sheet, strip or film can be produced by a method comprising:

[0073] FIG. 1 shows an X-ray diffraction measurement of an embodiment of a material containing silicon, calcium, potassium, zirconium, and oxygen after heat treatment, where the material formed is potassium feldspar.

[0074] In some embodiments, the active material is a material configured to hold a certain amount of metal ions to store electrical energy. For example, the active material can be porous silicon or semi-metal oxides (MeO), silicon-based materials such as SiO, prepared by the methods described above. x(Here, 0 < x < 2), and / or a high-capacity silicon-based material having a plurality of sites that can accept a certain amount of metal ions (e.g., Na, K, Rb, Cs, Ca, Al, Mg, Sr, Sc, Y, Zr, Ti, La, Ce, Hf ions) through a suitable chemical reaction between the active material and the metal ions may also be used.

[0075] During the "charging" period (when current / electrons are supplied from an external source), lithium ions adhere to the vacancies of silicon in the active material to form an Si / Li alloy, so lithium is inserted into the active material. Conversely, in the "discharging" process (when the material supplies electrons / current to the equipment it is connected to), lithium ions separate from the Si / Li alloy. The electrolyte in contact with the active material can supply lithium ions.

[0076] As an example, the active material includes one or more metal elements (e.g., Zn, Ga, In, Sn, Pb, and Bi), one or more metal oxides (e.g., ZnO, Ga2O3, Ga2O, In2O3, SnO, SnO2, PbO, Pb3O4, PbO2, Pb2O3, Pb 12 O 19 , Bi2O3), alloys of one or more of these metal elements and / or conversion-type materials, but are not limited thereto. In battery applications, these materials can react with metal elements to store or release energy (preferably electrical energy).

[0077] During the "charging" process, lithium ions adhere to the metal oxides in the active material and convert the metal oxides into lithium oxides and lithium metal alloys, thereby embedding lithium into the active material. In the "discharging" process, lithium ions are extracted into the electrolyte and the metal is converted into metal oxides.

[0078] The preloaded raw material contains one or more metal atoms preloaded into the active material by a treatment process. The precursor of the metal atom is preferably at least one of the forms of elemental metal (A), metal oxide (A-O), metal hydroxide (A-OH), metal acetate (A-CH3COOH), metal nitrate (A-NO3), metal sulfate (A-SO4), and metal carbonate (A-CO3). The precursor of the metal atom contains one or more metal atoms selected from Na, K, Rb, Cs, Ca, Al, Mg, Sr, Sc, Y, Zr, Ti, La, Ce, and Hf.

[0079] The preloaded metal atoms serve as an "adhesive" for the active material, sticking multiple separate parts of the active material together. The metal atoms can form a complex with the active material and bond the oxygen atoms of the active material into the complex.

[0080] For example, the empirical formula of the material according to the present invention is A y MeO x (where A is one or more selected from metal atoms consisting of Na, K, Rb, Cs, Ca, Al, Mg, Sr, Sc, Y, Zr, Ti, La, Ce, Hf, Me is a metalloid such as Si, B, O is oxygen, 0 < x < 4, and 0 < y < 4). The size of the basic particles of the material according to the present invention may be 5 nm to 5 mm.

[0081] In particular, the preloaded metal atoms hold oxygen atoms of SiO x (where 0 < x < 2) within each part of the active material, and can deactivate the oxygen atoms of SiO x (0 < x < 2) and SiO2 within each part of the active material. Each of the metal atoms and oxygen atoms shares an electron pair between them to form a covalent bond. Since the metal atoms are bonded to the oxygen atoms, during the battery charging period and / or discharging period, the metal atoms remain bonded to the oxygen atoms of the active material.

[0082] The structure of the complex is described in detail below. The active material forms a complex with a metal atom and an oxygen atom. In the complex, the atoms are arranged in an orderly or disordered manner, which results in the formation of polycrystalline or amorphous regions within the preloaded material. Therefore, the preloaded material loaded with the metal atoms becomes an amorphous or polycrystalline material. The resulting material containing the A-Me-O formation is non-reactive in an air environment.

[0083] By retaining the oxygen atoms with preloaded metal atoms and deactivating the oxygen atoms, the material of the present invention can have a significantly improved coulombic efficiency.

[0084] <Method for preparing battery materials> The method for preparing a battery material according to the present invention includes preloading an active material with one or more metal atoms, the active material being configured to undergo a chemical reaction during charging and / or discharging of the battery, and the metal atoms being configured to retain one or more oxygen atoms on the surface of the active material and deactivate the one or more oxygen atoms on the surface of the active material during charging and / or discharging of the battery.

[0085] Taking a metalloid (Me)-based material as an example, a number of metal atoms (A) selected from Na, K, Rb, Cs, Ca, Al, Mg, Sr, Sc, Y, Zr, Ti, La, Ce, and Hf are preloaded into the structure of the material. The metal atoms (A) can react with oxygen (O) on the surface of the metalloid (Me)-based material and form an A-Me-O complex (i.e., an oxidized state) with the metalloid (Me). The metal atoms inactivate the oxygen, thereby reducing the effect of oxygen and solving the problem of low Coulombic efficiency. This can therefore improve the electrochemical performance of the metalloid material when used in batteries.

[0086] In some embodiments, the metal atoms are preloaded into the active material by the following method. That is, the active material and a material containing the metal atoms are annealed at an annealing temperature of 500°C to 1200°C in an atmosphere of at least one selected from helium gas, nitrogen gas, and argon gas, thereby preloading the active material with the metal atoms. In the above-described method, the material containing the metal atoms is a metal salt or a metal oxide. The metal salt may be a carbonate, nitrate, acetate, or sulfate. The annealing temperature is preferably 800°C to 1150°C, more preferably 1000°C to 1100°C. The present invention has discovered that appropriately increasing the annealing temperature improves the coulombic efficiency of the battery.

[0087] In some other embodiments, the metal atoms are preloaded onto the active material in the following manner.

[0088] That is, the active material and the material containing metal atoms are subjected to a ball mill or a high-energy ball mill, mixed with each other, and then heat-treated in at least one atmosphere selected from helium gas, nitrogen gas, and argon gas. In the above-described method, the material containing metal atoms is a metal salt or a metal oxide. The metal salt may be a carbonate, nitrate, acetate, or sulfate. The heat treatment temperature may be 500°C to 1200°C, preferably 800°C to 1150°C, and more preferably 1000°C to 1100°C. The present inventors have found that appropriately increasing the heat treatment temperature improves the coulombic efficiency of the battery.

[0089] <Battery and preparation method> The material according to the present invention is used in batteries, including, but not limited to, lithium ion batteries, sodium ion batteries, potassium ion batteries, calcium ion batteries, magnesium ion batteries, and lithium-sulfur batteries. Preferably, the material according to the present invention is used as a negative electrode material in the battery.

[0090] In some embodiments, an exemplary battery structure is provided, comprising a negative electrode made of a material according to the present invention, a positive electrode, and an electrolyte in communication with the positive and negative electrodes, wherein ions can migrate through the electrolyte during charge and discharge cycles. The battery according to the present invention may include a positive electrode, a negative electrode, and an electrolyte, wherein the negative electrode is made of a material according to the present invention, and the electrolyte is in ionic communication between the negative electrode and the positive electrode. In some embodiments, during charging of the battery, metal ions from the positive electrode migrate to the negative electrode, and during discharging of the battery, the metal ions return to the positive electrode. During discharging of the battery, the metal ions are not trapped by oxygen atoms in the negative electrode.

[0091] Optionally, the battery may include a separator that provides electrical insulation between the positive electrode and the negative electrode. The positive electrode is suitable for releasing metal ions, such as lithium, sodium, potassium, calcium, and magnesium ions, while the negative electrode accepts metal ions from the positive electrode.

[0092] During each "charge" cycle of a battery, metal ions (e.g., lithium, sodium, potassium, calcium, and magnesium ions) migrate from the positive electrode to the negative electrode. Then, during the "discharge" phase, the metal ions present at the negative electrode are transferred back to the positive electrode.

[0093] Advantageously, in the discharging process of metal ions, the metal atoms preloaded in the material of the present invention as the negative electrode play an important role: oxygen atoms in the negative electrode are bonded to the preloaded metal atoms, so that during the discharging period of the battery, the metal ions are not trampled by the oxygen atoms in the negative electrode, and the dissolution of the active material in the electrolyte is suppressed.

[0094] The battery can be manufactured by conventional methods. The material of the present invention, conductive carbon black, and sodium carboxymethyl cellulose are mixed, and an appropriate amount of deionized water (solvent) is added. The mixture is mixed uniformly to prepare a slurry. The slurry is evenly spread on copper foil with a spatula, dried in a vacuum, and then punched into a circular electrode sheet using a die. The circular electrode sheet and a metallic lithium sheet are then used to assemble the battery.

[0095] Next, the following tests were carried out using specific examples of the above-described manufacturing process and the material according to the present invention. The test methods used in the following examples and comparative examples were conventional methods unless otherwise specified. All materials, reagents, etc. used in the following examples and comparative examples were commercially available unless otherwise specified.

[0096] The test method will be explained below.

[0097] SEM: The morphology of the powders is examined by scanning electron microscope (SEM, Philips XL30FEG).

[0098] XRD: Tests were performed using an X-ray diffractometer (XRD, D2 Phaser Brucker). The scanning range was 10° to 80°, the scanning speed was 0.05° / s, and the X-ray source was CuKα radiation (λ = 0.154178 nm).

[0099] Electrical performance test: The material obtained in the examples or comparative examples, conductive carbon black (Acetylene Black), and sodium carboxymethylcellulose were mixed in a mass ratio of 8:1:1, and an appropriate amount of deionized water (solvent) was added. The mixture was mixed uniformly in an agate mortar to prepare a slurry. The slurry was evenly spread onto copper foil with a spatula and dried at 80°C in a vacuum for 4 hours. After that, a circular electrode sheet with a diameter of 16 mm was punched out using a mold. This circular electrode sheet was used as the target electrode, and a metallic lithium sheet was used as the counter electrode. A 2032-type button battery was assembled in a glove box.

[0100] The electrochemical test was carried out using a Neware battery test system, with the charge / discharge current density set to 250mA / g, the charge / discharge cut-off voltage set to 0.01~1V, and the test temperature set to 25℃. Example 1 67 g of magnesium and 33 g of silicon particles were placed in a high-temperature furnace, and the air in the furnace was evacuated to 0.01% atmospheric pressure using an air pump, and then filled with argon gas with a purity of 99.99% as an inert protective atmosphere.

[0101] Magnesium and silicon particles were heated to 1100°C, kept at that temperature for 2 hours, and then naturally cooled. After that, the magnesium silicon alloy was taken out and crushed.

[0102] The crushed magnesium silicon alloy was placed in a vacuum furnace, and the gas in the furnace was evacuated to 0.001% atmospheric pressure using a molecular pump, and the temperature was heated to 800 °C, and then vacuum distillation was carried out to dealloy the alloy to obtain a porous silicon material.

[0103] 10 g of porous silicon material was placed in a 50 ml zirconia ball mill jar, 60 g of 1 cm diameter zirconia balls were added, and the mixture was milled at 400 rpm for 1.5 hours to obtain porous silicon particles with a particle size of 1 to 5 μm. Figure 1 shows an SEM image of the porous silicon particles. As can be seen from Figure 1, the porous silicon particles had an irregular polygonal shape, particle sizes of 1 to 5 μm, and few nanoparticles. Because of the porous structure of the silicon particles, their mechanical strength was reduced, and they were milled using a low-energy ball mill to obtain a powder with a relatively uniform particle size. Figure 2 shows the pore size distribution of the porous silicon particles. In the following examples and comparative examples, porous silicon particles with similar properties were obtained using the above method.

[0104] 0.4 g of calcium oxide, 0.4 g of potassium oxide, and 1 g of zirconia were placed in a ball mill jar and subjected to a ball mill treatment under an argon atmosphere to obtain a composite material.

[0105] The composite material was heated to 1100°C under an argon atmosphere and kept at that temperature for 3 hours to obtain a battery material. The electrical properties of the obtained material are shown in Table 1.

[0106] Figure 3 shows the XRD pattern of the battery material obtained in this example. Figure 3 shows the peak of the compound formed by metal atom A and the elemental silicon oxide layer, indicating that a solid-state chemical reaction occurred between the metal atom and the elemental silicon oxide layer, proving that the present invention has successfully prepared an A-Si-O porous silicon composite material.

[0107] Example 2 67 g of magnesium and 33 g of silicon particles were placed in a high-temperature furnace, and the air in the furnace was evacuated to 0.01% atmospheric pressure using an air pump, and then filled with argon gas with a purity of 99.99% as an inert protective atmosphere.

[0108] Magnesium and silicon particles were heated to 1100°C, kept at that temperature for 2 hours, and then naturally cooled. After that, the magnesium silicon alloy was taken out and crushed.

[0109] The crushed magnesium silicon alloy was placed in a vacuum furnace, and the gas in the furnace was evacuated to 0.001% atmospheric pressure using a molecular pump, and the temperature was heated to 800 °C, and then vacuum distillation was carried out to dealloy the alloy to obtain a porous silicon material.

[0110] 10 g of the porous silicon material was placed in a 50 ml zirconia ball mill jar, 60 g of zirconia balls with a diameter of 1 cm were added, and polishing was carried out at a rotation speed of 400 rpm for 1.5 hours to obtain porous silicon particles with a particle diameter of 1 to 5 μm.

[0111] 1 g of yttrium oxide was added to a ball mill jar and subjected to ball milling in an argon atmosphere to obtain a composite material.

[0112] The composite material was heated to 1100°C in an argon atmosphere and kept at that temperature for 3 hours to obtain a battery material. The electrical properties of the obtained material are shown in Table 1.

[0113] Figure 4 shows the XRD pattern of the battery material obtained in this example. Figure 4 shows the pick of a compound formed from metal atoms A and the elemental silicon oxide layer, indicating that the metal atoms and the elemental silicon oxide layer underwent a solid-state chemical reaction, proving that the present invention has successfully prepared an A-Si-O porous silicon composite material.

[0114] Example 3 67 g of magnesium and 33 g of silicon particles were placed in a high-temperature furnace, and the air in the furnace was evacuated to 0.01% atmospheric pressure using an air pump, and then filled with argon gas with a purity of 99.99% as an inert protective atmosphere.

[0115] Magnesium and silicon particles were heated to 1100°C, kept at that temperature for 2 hours, and then naturally cooled. After that, the magnesium silicon alloy was taken out and crushed.

[0116] The crushed magnesium silicon alloy was placed in a vacuum furnace, and the gas in the furnace was evacuated to 0.001% atmospheric pressure using a molecular pump, and the temperature was heated to 800 °C, and then vacuum distillation was carried out to dealloy the alloy to obtain a porous silicon material.

[0117] 10 g of the porous silicon material was placed in a 50 ml zirconia ball mill jar, 60 g of zirconia balls with a diameter of 1 cm were added, and polishing was carried out at a rotation speed of 400 rpm for 1.5 hours to obtain porous silicon particles with a particle diameter of 1 to 5 μm.

[0118] 0.5 g of alumina and 0.5 g of potassium oxide were added to a ball mill jar and subjected to a ball milling treatment in an argon atmosphere to obtain a composite material.

[0119] The composite material was heated to 1100°C in an argon gas atmosphere and kept at that temperature for 3 hours to obtain a battery material. The electrical properties of the obtained material are shown in Table 1.

[0120] Figure 5 shows the XRD pattern of the battery material obtained in this example. Figure 5 shows the pick of a compound formed from metal atoms A and the elemental silicon oxide layer, indicating that the metal atoms and the elemental silicon oxide layer underwent a solid-state chemical reaction, proving that the present invention successfully prepared an A-Si-O porous silicon composite material.

[0121] Comparative Example 1 Ten grams of nanosilicon material (approximately 100 nm in diameter) was placed in a 50 ml zirconia ball mill jar, 60 g of 1 cm diameter zirconia balls were added, and 1 g of yttrium oxide was added to the ball mill jar. The mixture was then polished in an argon atmosphere at 400 rpm for 1.5 hours to obtain a composite material.

[0122] The composite material was heated to 1100°C in an argon gas atmosphere and kept at that temperature for 3 hours to obtain a battery material. The electrical properties of the obtained material are shown in Table 1.

[0123] Comparative Example 2 67 g of magnesium and 33 g of silicon particles were placed in a high-temperature furnace, and the air in the furnace was evacuated to 0.01% atmospheric pressure using an air pump, and then filled with argon gas with a purity of 99.99% as an inert protective atmosphere.

[0124] Magnesium and silicon particles were heated to 1100°C, kept at that temperature for 2 hours, and then naturally cooled. After that, the magnesium silicon alloy was taken out and crushed.

[0125] The crushed magnesium silicon alloy was placed in a vacuum furnace, and the gas in the furnace was evacuated to 0.001% atmospheric pressure using a molecular pump, and the temperature was heated to 800 °C, and then vacuum distillation was carried out to dealloy the alloy to obtain a porous silicon material.

[0126] 10 g of porous silicon material was placed in a 50 ml zirconia ball mill jar, 60 g of 1 cm diameter zirconia balls were added, and polishing was carried out at 400 rpm for 1.5 hours to obtain porous silicon particles with particle diameters of 1 to 5 μm. The electrical properties of the obtained porous silicon particles are shown in Table 1.

[0127] Comparing Examples 1-3 and Comparative Example 2, preloading with metal atoms can improve the initial coulombic efficiency by approximately 2%, even up to 4%. Such a significant improvement is already remarkable in the art. Therefore, preloading an active material with metal atoms, which is the negative electrode material, is not something that would be easily conceived by those skilled in the art. Comparing Example 2 and Comparative Example 1, employing micron-sized porous silicon particles instead of nanosilicon material is advantageous for significantly improving the initial coulombic efficiency and improving the initial charge and discharge capacities. Given these excellent technical effects, using micron-sized porous silicon particles instead of nanosilicon material is not a conventional option in the art. As is clear from Table 1, batteries using the material of the present invention as the negative electrode exhibit excellent electrochemical performance due to their high coulombic efficiency and electrical capacity.

Claims

1. an active material arranged to undergo a chemical reaction during charging and / or discharging of the battery; and one or more metal atoms arranged to retain and passivate one or more oxygen atoms of the active material during charging and / or discharging of the battery; A battery material comprising:

2. The material of claim 1 , wherein the metal atom forms a complex with the active material.

3. 3. The material of claim 2, wherein the metal atoms are arranged within the complex to bond to oxygen atoms on the surface of the active material.

4. 4. The material of claim 3, wherein the metal atoms are covalently bonded to oxygen atoms on the surface of the active material.

5. 5. The material of claim 4, wherein the metal atoms remain bonded to the oxygen atoms during charging and / or discharging of the battery.

6. 6. The material of claim 5, wherein said metal atoms react with said oxygen atoms to form an oxide within said complex.

7. 7. The material of claim 6, wherein the oxide forms at least one of an amorphous material and a polycrystalline material.

8. 8. The material of claim 7, wherein the metal atoms retain and deactivate the oxygen atoms, thereby increasing the coulombic efficiency of the material.

9. 2. The material according to claim 1, wherein the metal atom is one or more selected from the group consisting of Na, K, Rb, Cs, Ca, Al, Mg, Sr, Sc, Y, Zr, Ti, La, Ce, and Hf.

10. 10. The material of claim 9, wherein the metal atoms are embedded in the active material to retain and passivate the oxygen atoms.

11. 11. The material of claim 10, wherein the metal atoms are embedded in the active material as at least one of an elemental metal, a metal oxide, a metal hydroxide, a metal acetate, a metal nitrate, a metal sulfate, and a metal carbonate.

12. The material according to claim 1, wherein the active material is one or more selected from the group consisting of metalloid elements, oxides of metalloid elements, metal elements, and oxides of metal elements.

13. 13. The material according to claim 12, characterized in that the metalloid element is Si and / or B.

14. The active material is Si and SiO ｘ (where 0<x<2) and SiO ２ The material according to claim 12, characterized in that it comprises at least one of:

15. 2. The material of claim 1, wherein the active material is in particulate form, and the particle size of the active material is between 5 nm and 5 mm.

16. 10. The material of claim 1, wherein the active material is used as an anode material in the battery.

17. A battery comprising a positive electrode, a negative electrode, and an electrolyte, wherein the negative electrode is made of the material according to any one of claims 1 to 16, and the electrolyte is in ionic communication with the negative electrode and the positive electrode.

18. 18. The battery of claim 17, wherein metal ions from the positive electrode migrate to the negative electrode during charging of the battery, and the metal ions return to the positive electrode during discharging of the battery.

19. 20. The battery of claim 18, wherein the metal ions are not trapped by oxygen atoms in the negative electrode during discharge of the battery.

20. 19. The battery according to claim 18, wherein the metal ions are one or more selected from the group consisting of Li, Na, K, Ca, and Mg.

21. preloading an active material with one or more metal atoms, the active material being configured to undergo a chemical reaction during charging and / or discharging of the battery, the metal atoms being configured to retain one or more oxygen atoms on the surface of the active material and passivate one or more oxygen atoms on the surface of the active material during charging and / or discharging of the battery; A method for preparing the battery material according to any one of claims 1 to 16, comprising:

22. A method for preloading the metal atoms into the active material by annealing the active material and the material containing the metal atoms at an annealing temperature of 500°C to 1200°C in an atmosphere of at least one kind selected from helium gas, nitrogen gas, and argon gas, 22. The method of claim 21, wherein the active material is preloaded with one or more metal atoms.

23. 23. The method of claim 22, wherein increasing the annealing temperature increases the coulombic efficiency of the cell.

24. a method for treating the active material and the material containing metal atoms in a high-energy ball mill, mixing the active material and the material containing metal atoms, and then heat-treating the mixture in an atmosphere of at least one selected from helium gas, nitrogen gas, and argon gas; 22. The method of claim 21, wherein the metal atoms are preloaded into the active material.

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