WO2023205993A1 - 尖晶石镍锰酸锂材料及其制备方法 - Google Patents

尖晶石镍锰酸锂材料及其制备方法 Download PDF

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WO2023205993A1
WO2023205993A1 PCT/CN2022/088926 CN2022088926W WO2023205993A1 WO 2023205993 A1 WO2023205993 A1 WO 2023205993A1 CN 2022088926 W CN2022088926 W CN 2022088926W WO 2023205993 A1 WO2023205993 A1 WO 2023205993A1
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lithium nickel
spinel lithium
manganate material
nickel manganate
material according
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PCT/CN2022/088926
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English (en)
French (fr)
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范敬鹏
张振国
柳娜
吴奇
陈强
赵栋
王婧
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宁德时代新能源科技股份有限公司
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Priority to EP22938761.8A priority Critical patent/EP4318662A1/en
Priority to JP2023569723A priority patent/JP2024519759A/ja
Priority to KR1020237034977A priority patent/KR20230154276A/ko
Priority to PCT/CN2022/088926 priority patent/WO2023205993A1/zh
Priority to CN202280032770.7A priority patent/CN117321798A/zh
Publication of WO2023205993A1 publication Critical patent/WO2023205993A1/zh

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    • C01G53/40—Nickelates
    • C01G53/42—Nickelates containing alkali metals, e.g. LiNiO2
    • C01G53/44—Nickelates containing alkali metals, e.g. LiNiO2 containing manganese
    • C01G53/54—Nickelates containing alkali metals, e.g. LiNiO2 containing manganese of the type [Mn2O4]-, e.g. Li(NixMn2-x)O4, Li(MyNixMn2-x-y)O4
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    • C30B1/02—Single-crystal growth directly from the solid state by thermal treatment, e.g. strain annealing
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    • C30B29/10—Inorganic compounds or compositions
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    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
    • H—ELECTRICITY
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    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
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    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the invention relates to the field of electrochemistry, and in particular to spinel lithium nickel manganate materials and preparation methods thereof.
  • the discharge voltage platform of spinel lithium nickel manganate is as high as 4.7V (vs Li/Li + ), and the theoretical discharge specific capacity is high (147mAh/g), so it has a high theoretical specific energy density (690Wh/kg).
  • the specific energy density of spinel lithium nickel manganese oxide currently used in graphite negative electrode full batteries is also higher than 590Wh/kg, much higher than lithium iron phosphate ( ⁇ 460Wh/kg), and similar to ternary nickel cobalt manganese ( ⁇ 650Wh/kg). kg), and there is still much room for improvement in spinel lithium nickel manganate.
  • the Li and Ni contents in spinel lithium nickel manganese oxide are significantly lower than that of ternary nickel cobalt manganese, and the preparation process is simple.
  • spinel lithium nickel manganate has high energy density, low cost and high safety, so it is a very potential low-cost and high-energy-density cathode material.
  • Synthesizing spinel lithium nickel manganate under high temperature conditions can easily cause oxygen deficiency in the material, resulting in a large number of oxygen defects and rock salt phases, resulting in a reduction in the structural stability of the material, which in turn results in poor cycle performance.
  • Mn 3+ in spinel lithium nickel manganate is prone to disproportionation reaction.
  • Mn 2+ is dissolved in the electrolyte and deposited on the negative electrode.
  • a large number of side reactions occur between the material surface and the electrolyte. Leading to an overall deterioration in battery performance.
  • the current research focus is to reduce the oxygen defects of spinel lithium nickel manganate, enhance the stability of the crystal structure, and reduce the rock salt phase content, thereby improving the rate performance, cycle performance, and storage performance of the cathode material, thereby improving the use
  • the cathode material improves battery energy density and long cycle life.
  • This application was made in view of the above technical problems, and its purpose is to provide a spinel lithium nickel manganate material and a preparation method thereof, a secondary battery including the spinel lithium nickel manganate material, and a battery module.
  • the spinel lithium nickel manganate material of the present application can reduce oxygen defects, enhance the stability of the crystal structure, and reduce the rock salt phase content.
  • the first aspect of the present application is to provide a spinel lithium nickel manganate material, wherein,
  • the conditions satisfied in the XRD pattern of the spinel lithium nickel manganate material are: 0 ⁇ (A(43.7°)/A(18.8°)) 1/2 ⁇ 0.2, preferably the conditions satisfied are: 0 ⁇ ( A(43.7°)/A(18.8°)) 1/2 ⁇ 0.1,
  • A(43.7°) represents the peak area of the diffraction peak appearing near 43.7° in the XRD pattern
  • A(18.8°) represents the peak area of the diffraction peak appearing near 18.8° in the XRD pattern.
  • the stoichiometric formula of the spinel lithium nickel manganate material is Li x (Ni 0.5 Mn 1.5 ) n M m O 4 , where M is selected from W, P, B, Nb, Mo
  • M is selected from W, P, B, Nb, Mo
  • the spinel lithium nickel manganate material is a single crystal octahedron with passivated corners.
  • the spinel lithium nickel manganate is modified by doping the above elements in a specific amount, so that the obtained spinel lithium nickel manganate material forms an octahedral single crystal morphology with passivated edges, in which the passivated edges
  • the angle can reduce the surface activity of spinel lithium nickel manganese oxide and reduce the contact area with the electrolyte, thereby reducing side reactions; the single crystal morphology can effectively reduce the cracking phenomenon during cold pressing and battery use, improving the efficiency of the battery. overall performance.
  • the volume distribution average particle size Dv50 of the spinel lithium nickel manganate material is 5 ⁇ m to 15 ⁇ m, preferably 5 ⁇ m to 10 ⁇ m.
  • the particle volume distribution diameter (Dv90-Dv10)/Dv50 of the spinel lithium nickel manganate material is less than 1.0.
  • the BET of the nickel-manganese spinel material is 0.3m 2 /g ⁇ 1.0m 2 /g, preferably 0.3m 2 / g ⁇ 0.5m 2 /g.
  • the second aspect of this application is to provide a method for preparing the spinel lithium nickel manganate material involved in the first aspect, wherein,
  • the preparation method includes the following steps S1 to S3,
  • S2 The mixed material obtained in S1 is heated in an oxygen-rich atmosphere for the first sintering. After the first sintering is completed, it is naturally cooled to room temperature, and then ball milled to obtain powder;
  • S3 The powder obtained in S2 is heated again in an oxygen-rich atmosphere for a second sintering. After the second sintering is completed, it is kept warm, then naturally cooled to room temperature, and then ball milled to obtain a spinel lithium nickel manganate material.
  • the inventive spinel lithium nickel manganate material obtained by the above preparation method has less oxygen defects, side reactions and Mn dissolution, and has excellent comprehensive electrochemical properties.
  • the mixing ratio of lithium salt and nickel manganese hydroxide is (0.45 ⁇ 0.55):1 based on Li/(Ni+Mn) molar ratio, where (Ni+Mn) is The total metal moles of nickel and manganese, and the doping amount of the M-containing compound is 1:(0.001 ⁇ 0.01) in terms of Li/M molar ratio, preferably 1:(0.003 ⁇ 0.007) in terms of Li/M molar ratio. .
  • the doping amount of the M-containing compound within the above range, and setting the mixing ratio of lithium salt and nickel manganese hydroxide within the above range, the crystal morphology of the spinel lithium nickel manganate material can be effectively controlled. , effectively reduce oxygen defects and side reactions between the spinel lithium nickel manganate material and the electrolyte, improve the structural stability of the spinel lithium nickel manganate material, and reduce Mn dissolution.
  • the mixer in step S1, is a plow mixer, a high mixer or an inclined test mixer. By using these mixers, mixing efficiency can be effectively improved.
  • the temperature rise rate during the first sintering and the second sintering is 5°C/min or less, preferably 3°C/min or less. Since the heating rate affects the heating of the material during the crystallization process, setting the heating rate within the above range ensures that the primary particles are more uniform.
  • the first sintering temperature is 500°C to 1200°C, preferably 600°C to 1200°C
  • the second sintering temperature is 400°C to 700°C, preferably 600°C to 1200°C. 500°C ⁇ 700°C.
  • the second sintering annealing of the spinel lithium nickel manganate material can make up for the oxygen defects in the first sintering annealing process, further reducing the oxygen defects in the material, and effectively reducing the Mn 3+ content in the material. Reduce Mn dissolution. Since the spinel lithium nickel manganate is doped with one or more elements selected from W, P, B, Nb, Mo and Ta, the first sintering temperature and the second sintering temperature can be respectively The synthesis is carried out within the above lower temperature range.
  • the oxygen content is greater than 60%, preferably 80% to 100%.
  • the pressure in the sintering furnace is 0.02MPa ⁇ 0.08MPa relative to the atmospheric pressure, preferably 0.02MPa ⁇ 0.04MPa.
  • the holding time is 5h to 40h, preferably 15h to 30h.
  • a third aspect of the present application is to provide a secondary battery, which includes the spinel lithium nickel manganate material according to the first aspect of the present application.
  • a fourth aspect of the present application is to provide a battery module, which includes the secondary battery according to the third aspect of the present application.
  • a fifth aspect of the present application is to provide a battery pack, which includes the battery module according to the fourth aspect of the present application.
  • the sixth aspect of the present application is to provide an electrical device, which includes the secondary battery according to the third aspect of the present application, the battery module according to the fourth aspect of the present application, and the secondary battery according to the fifth aspect of the present application. at least one of the battery packs described above.
  • the spinel lithium nickel manganate material of the present invention as a cathode material, the spinel lithium nickel manganate material has low oxygen defect content, strong crystal structure stability, and low rock salt phase content. Furthermore, using this cathode material The secondary battery has high energy density and long cycle life, and the gas production problem during the cycle is effectively suppressed.
  • Figures 1a, 1b, and 1c are XRD patterns of the spinel lithium nickel manganate material according to one embodiment of the present application.
  • Figures 2a and 2b are SEM images of particles of spinel lithium nickel manganate material according to another embodiment of the present application.
  • FIG. 3 is a schematic diagram of a secondary battery according to an embodiment of the present application.
  • FIG. 4 is an exploded view of the secondary battery according to one embodiment of the present application shown in FIG. 3 .
  • FIG. 5 is a schematic diagram of a battery module according to an embodiment of the present application.
  • Figure 6 is a schematic diagram of a battery pack according to an embodiment of the present application.
  • FIG. 7 is an exploded view of the battery pack according to one embodiment of the present application shown in FIG. 6 .
  • FIG. 8 is a schematic diagram of a power consumption device using a secondary battery as a power source according to an embodiment of the present application.
  • Figures 9a, 9b, and 9c are XRD patterns of the spinel lithium nickel manganate material in Example 1 of the present application.
  • Figures 10a, 10b, and 10c are XRD patterns of the spinel lithium nickel manganate material of Comparative Example 1 of the present application.
  • Figures 11a and 11b are SEM images of the Zr-doped spinel lithium nickel manganate material of Comparative Example 11 of the present application.
  • Figures 12a and 12b are SEM images of undoped spinel lithium nickel manganate material.
  • Ranges disclosed herein are defined in terms of lower and upper limits. A given range is defined by selecting a lower limit and an upper limit that define the boundaries of the particular range. Ranges defined in this manner may be inclusive or exclusive of the endpoints, and may be arbitrarily combined, that is, any lower limit may be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a particular parameter, understand that ranges of 60-110 and 80-120 are also expected. Additionally, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, then the following ranges are all expected: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 ⁇ 4 and 2 ⁇ 5.
  • the numerical range “a ⁇ b” represents an abbreviated representation of any combination of real numbers between a and b, where a and b are both real numbers.
  • the numerical range “0 ⁇ 5" means that all real numbers between "0 ⁇ 5" have been listed in this article, and "0 ⁇ 5" is just an abbreviation of these numerical combinations.
  • a certain parameter is an integer ⁇ 2
  • condition "A or B” is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists) ; Or both A and B are true (or exist).
  • the conditions satisfied in the XRD pattern of the spinel lithium nickel manganate material of the present application are: 0 ⁇ (A(43.7°)/A(18.8°)) 1/2 ⁇ 0.2.
  • the conditions satisfied are: 0 ⁇ (A(43.7°)/A(18.8°)) 1/2 ⁇ 0.1, where A(43.7°) represents the peak area of the diffraction peak appearing near 43.7° in the XRD pattern, and A(18.8°) represents The peak area of the diffraction peak appearing near 18.8° in the XRD pattern.
  • the spinel lithium nickel manganate material of the present invention has a diffraction peak near 43.7°, and a diffraction peak appears near 18.8°. From this, it can be obtained that the spinel lithium nickel manganate material appears near 43.7°.
  • the peak area of the diffraction peak and the peak area of the diffraction peak appearing near 18.8° are further calculated to be (A(43.7°)/A(18.8°)) 1/ of the spinel lithium nickel manganate material of the present invention. 2 .
  • LiNi 0.5 Mn 1.5 O 4 When spinel lithium nickel manganate (LiNi 0.5 Mn 1.5 O 4 ) is heated above a certain temperature, LiNi 0.5 Mn 1.5 O 4 will lose oxygen and disproportionate into spinel and Li x Ni 1-x O.
  • the diffraction peak intensity at 37.6° and 63.5° is extremely low, so 43.7° is used to define the oxygen defect content.
  • 18.8° is used to define the reference peak.
  • the stoichiometric formula of the spinel lithium nickel manganate material of the present application is Li x (Ni 0.5 Mn 1.5 ) n M m O 4 , where M is selected from W, P, B, Nb, Mo and Ta.
  • M is selected from W, P, B, Nb, Mo and Ta.
  • the doping element M can effectively affect the particle morphology and make the corners of its perfect octahedron passivated, as shown in Figure 2a and Figure 2b, which proves that the spinel lithium nickel manganate material of the present invention is single crystal and has blunt corners.
  • the morphological characteristics of the octahedron are important to affect the particle morphology and make the corners of its perfect octahedron passivated, as shown in Figure 2a and Figure 2b, which proves that the spinel lithium nickel manganate material of the present invention is single crystal and has blunt corners.
  • the spinel lithium nickel manganate material of the present application has a volume distribution average particle diameter Dv50 of 5 to 15 ⁇ m, preferably 5 to 10 ⁇ m.
  • the size of Dv50 mainly affects the contact surface between the material and the electrolyte, thereby affecting the side reactions between the material and the electrolyte.
  • the size of Dv50 is affected by the first sintering temperature and the second sintering temperature. As the temperature increases, the DV50 increases, so a larger Dv50 needs to be synthesized at a higher temperature.
  • the oxygen defects will also increase as the temperature increases, so the Dv50 is limited to not be too large, and the Dv50 is too large. If it is small, it will cause larger side reactions and lead to the deterioration of electrical properties.
  • the spinel lithium nickel manganate material has a particle volume distribution diameter (Dv90-Dv10)/Dv50 of 1.0 or less.
  • Particle volume distribution diameter (Dv90-Dv10)/Dv50 represents the size difference between individual particles in the material. The smaller the difference, the smaller the value. Moreover, its value mainly affects the side reactions between the material and the electrolyte.
  • the BET of the nickel-manganese spinel material is 0.3m 2 /g to 1.0m 2 /g, preferably 0.3m 2 /g to 0.5m 2 /g.
  • BET mainly affects the capacity development and side reactions of the spinel lithium nickel manganate material. A larger BET will provide a higher capacity but the side reactions will increase, so the BET must not be too large or too small. Furthermore, BET will also have an impact on the coating of spinel lithium nickel manganate materials.
  • the preparation method of the present invention includes the following steps S1 to S3,
  • S2 The mixed material obtained in S1 is heated in an oxygen-rich atmosphere for the first sintering. After the first sintering is completed, it is naturally cooled to room temperature, and then ball milled to obtain powder;
  • S3 The powder obtained in S2 is heated again in an oxygen-rich atmosphere for a second sintering. After the second sintering is completed, it is kept warm, then naturally cooled to room temperature, and then ball milled to obtain a spinel lithium nickel manganate material.
  • the inventive spinel lithium nickel manganate material obtained by the above preparation method has less oxygen defects, side reactions and Mn dissolution, and has excellent comprehensive electrochemical properties.
  • step S1 of the preparation method of the present invention the mixing ratio of lithium salt and nickel manganese hydroxide is (0.45 ⁇ 0.55):1 based on Li/(Ni+Mn) molar ratio, where, (Ni+Mn) is the total metal mole number of nickel and manganese, and the doping amount of the M-containing compound is 1:(0.001 ⁇ 0.01) based on the Li/M molar ratio, preferably 1:(0.003 ⁇ 0.007 based on the Li/M molar ratio ).
  • lithium salts include lithium carbonate and lithium hydroxide.
  • nickel manganese hydroxide include Ni 0.5 Mn 1.5 (OH) 7 .
  • M-containing compounds include M-containing chlorides, M-containing carbonates, M-containing sulfates, etc., that is, chlorides and carbonates of elements such as W, P, B, Nb, Mo, and Ta. , sulfate.
  • the doping amount of the M-containing compound within the above-mentioned Li/M molar ratio range, and setting the mixing ratio of lithium salt and nickel-manganese hydroxide within the above-mentioned Li/(Ni+Mn) molar ratio range , so that the doping element M will occupy the position and vacancies of the transition metal when entering the crystal lattice, which can effectively reduce the dissolution of the transition metal Mn in the material and the stability of the material structure.
  • the two are positively related, but too much M
  • the doping amount will greatly affect the electrical properties of the material, and if it is too small, the effect will not be reflected.
  • the selected doping elements can effectively increase the growth of primary particles, allowing the material to complete the second sintering at a lower temperature.
  • the lower second sintering temperature can effectively reduce the existence of oxygen defects.
  • the mixer can be a mixer commonly used in this field, and specific examples include: plow mixer, high mixer or inclined test mixer.
  • the temperature rise rate during sintering is 5°C/min or less, preferably 3°C/min or less. Controlling the heating rate can make each particle heated more uniformly during the growth process, resulting in a smaller volume distribution diameter (Dv90-Dv10)/Dv50. Dv50 is mainly related to the doping element and the first calcining temperature.
  • the first sintering temperature is 500°C to 1200°C, preferably 600°C to 1200°C
  • the second sintering temperature is 400°C to 700°C, Preferably it is 500°C to 700°C.
  • the first sintering in step S2 is the crystallization process of the spinel lithium nickel manganate material.
  • the morphology, Dv50, and electrical properties of the spinel lithium nickel manganate material are basically finalized in step S2, but in Higher temperatures during the first sintering process lead to an increase in oxygen defects.
  • the second sintering in step S3 is an annealing process of the spinel lithium nickel manganate material, which can compensate for the oxygen defects caused by the first sintering process in step S2 and further improve the performance of the spinel lithium nickel manganate material.
  • the oxygen content is greater than 60%, preferably 80% to 100%. Since oxygen-rich conditions will affect the oxygen defect content of the material, the oxygen content needs to be controlled within the above range.
  • the pressure in the sintering furnace is 0.02MPa ⁇ 0.08MPa relative to the atmospheric pressure, preferably 0.02MPa ⁇ 0.04MPa. Too large or too small furnace pressure will cause the material to produce a large number of small particles, resulting in a smaller Dv50, a larger particle volume distribution distance (Dv90-Dv10)/Dv50, and the air flow exchange will be affected, resulting in an increase in oxygen defect content. .
  • the holding time is 5h to 40h, preferably 15h to 30h.
  • the second sintering temperature is related to the holding time. Performing the second sintering within the range of step S3 can effectively reduce the oxygen defects and Mn 3+ content of the spinel lithium nickel manganate material. Mn 3+ undergoes a disproportionation reaction resulting in sharp Mn dissolution occurs in spar lithium nickel manganate materials, so the reduction of Mn 3+ content can effectively reduce Mn dissolution.
  • step S3 organic substances and/or inorganic substances commonly used in the art can also be added for coating, thereby reducing the use of spinel lithium nickel manganate materials when used in secondary batteries. Side reactions occur with the electrolyte.
  • a secondary battery is provided.
  • a secondary battery typically includes a positive electrode plate, a negative electrode plate, an electrolyte and a separator.
  • active ions are inserted and detached back and forth between the positive and negative electrodes.
  • the electrolyte plays a role in conducting ions between the positive and negative electrodes.
  • the isolation film is placed between the positive electrode piece and the negative electrode piece. It mainly prevents the positive and negative electrodes from short-circuiting and allows ions to pass through.
  • the positive electrode sheet includes a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector.
  • the positive electrode film layer includes the spinel lithium nickel manganate material of the first aspect of the present application as a positive electrode active material.
  • the positive electrode current collector has two surfaces facing each other in its own thickness direction, and the positive electrode film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.
  • the positive electrode current collector may be a metal foil or a composite current collector.
  • the metal foil aluminum foil can be used.
  • the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base layer.
  • the composite current collector can be formed by forming metal materials (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver and silver alloys, etc.) on polymer material substrates (such as polypropylene (PP), polyterephthalate It is formed on substrates such as ethylene glycol ester (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).
  • PP polypropylene
  • PBT polybutylene terephthalate
  • PS polystyrene
  • PE polyethylene
  • cathode active materials may adopt cathode active materials known in the art for use in batteries.
  • the cathode active material may include at least one of the following materials: an olivine-structured lithium-containing phosphate, a lithium transition metal oxide, and their respective modified compounds.
  • the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials of batteries can also be used. Only one type of these positive electrode active materials may be used alone, or two or more types may be used in combination.
  • lithium transition metal oxides may include, but are not limited to, lithium cobalt oxides (such as LiCoO 2 ), lithium nickel oxides (such as LiNiO 2 ), lithium manganese oxides (such as LiMnO 2 , LiMn 2 O 4 ), lithium Nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1/3 Co 1/3 Mn 1/3 O 2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O 2 (can also be abbreviated to NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O 2 (can also be abbreviated to NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O 2 (can also be abbreviated to NCM 622 ), LiNi At least one of 0.8 Co 0.1 Mn 0.1 O 2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as Li Li
  • the olivine structure contains Examples of lithium phosphates may include, but are not limited to, lithium iron phosphate (such as LiFePO 4 (also referred to as LFP)), composites of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), lithium manganese phosphate and carbon. At least one of composite materials, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon.
  • lithium iron phosphate such as LiFePO 4 (also referred to as LFP)
  • composites of lithium iron phosphate and carbon such as LiMnPO 4
  • LiMnPO 4 lithium manganese phosphate and carbon.
  • At least one of composite materials, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon At least one of composite materials, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon.
  • the positive electrode film layer optionally further includes a binder.
  • the binder may include polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene At least one of ethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer and fluorine-containing acrylate resin.
  • the positive electrode film layer optionally further includes a conductive agent.
  • the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers.
  • the positive electrode sheet can be prepared by dispersing the above-mentioned components for preparing the positive electrode sheet, such as positive active material, conductive agent, binder and any other components in a solvent (such as N -methylpyrrolidone) to form a positive electrode slurry; the positive electrode slurry is coated on the positive electrode current collector, and after drying, cold pressing and other processes, the positive electrode piece can be obtained.
  • a solvent such as N -methylpyrrolidone
  • the negative electrode sheet includes a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector, where the negative electrode film layer includes a negative electrode active material.
  • the negative electrode current collector has two opposite surfaces in its own thickness direction, and the negative electrode film layer is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.
  • the negative electrode current collector may be a metal foil or a composite current collector.
  • the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base material.
  • the composite current collector can be formed by forming metal materials (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as polypropylene (PP), polyterephthalate It is formed on substrates such as ethylene glycol ester (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).
  • PP polypropylene
  • PBT polybutylene terephthalate
  • PS polystyrene
  • PE polyethylene
  • the negative active material may be a negative active material known in the art for batteries.
  • the negative active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, and the like.
  • the silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon carbon composites, silicon nitrogen composites and silicon alloys.
  • the tin-based material may be selected from at least one of elemental tin, tin oxide compounds and tin alloys.
  • the present application is not limited to these materials, and other traditional materials that can be used as battery negative electrode active materials can also be used. Only one type of these negative electrode active materials may be used alone, or two or more types may be used in combination.
  • the negative electrode film layer optionally further includes a binder.
  • the binder can be selected from styrene-butadiene rubber (SBR), polyacrylic acid (PAA), polyacrylic acid sodium (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), poly At least one of methacrylic acid (PMAA) and carboxymethyl chitosan (CMCS).
  • the negative electrode film layer optionally further includes a conductive agent.
  • the conductive agent may be selected from at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers.
  • the negative electrode film layer optionally also includes other auxiliaries, such as thickeners (such as sodium carboxymethylcellulose (CMC-Na)) and the like.
  • thickeners such as sodium carboxymethylcellulose (CMC-Na)
  • the negative electrode sheet can be prepared by dispersing the above-mentioned components for preparing the negative electrode sheet, such as negative active materials, conductive agents, binders and any other components in a solvent (such as deionized water) to form a negative electrode slurry; the negative electrode slurry is coated on the negative electrode current collector, and after drying, cold pressing and other processes, the negative electrode piece can be obtained.
  • a solvent such as deionized water
  • the electrolyte plays a role in conducting ions between the positive and negative electrodes.
  • the type of electrolyte in this application can be selected according to needs.
  • the electrolyte can be liquid, gel, or completely solid.
  • the electrolyte is an electrolyte solution.
  • the electrolyte solution includes electrolyte salts and solvents.
  • the electrolyte salt may be selected from the group consisting of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonimide, lithium bistrifluoromethanesulfonimide, trifluoromethane At least one of lithium sulfonate, lithium difluorophosphate, lithium difluoroborate, lithium dioxaloborate, lithium difluorodioxalate phosphate and lithium tetrafluoroxalate phosphate.
  • the solvent may be selected from the group consisting of ethylene carbonate, propylene carbonate, methylethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, Butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate At least one of ester, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone.
  • the electrolyte optionally further includes additives.
  • additives may include negative electrode film-forming additives, positive electrode film-forming additives, and may also include additives that can improve certain properties of the battery, such as additives that improve battery overcharge performance, additives that improve battery high-temperature or low-temperature performance, etc.
  • the secondary battery further includes a separator film.
  • a separator film There is no particular restriction on the type of isolation membrane in this application. Any well-known porous structure isolation membrane with good chemical stability and mechanical stability can be used.
  • the material of the isolation membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.
  • the isolation film can be a single-layer film or a multi-layer composite film, with no special restrictions. When the isolation film is a multi-layer composite film, the materials of each layer can be the same or different, and are not particularly limited.
  • the positive electrode piece, the negative electrode piece and the separator film can be made into an electrode assembly through a winding process or a lamination process.
  • the secondary battery may include an outer packaging.
  • the outer packaging can be used to package the above-mentioned electrode assembly and electrolyte.
  • the outer packaging of the secondary battery may be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc.
  • the outer packaging of the secondary battery may also be a soft bag, such as a bag-type soft bag.
  • the material of the soft bag may be plastic, and examples of the plastic include polypropylene, polybutylene terephthalate, polybutylene succinate, and the like.
  • FIG. 3 shows a square-structured secondary battery 5 as an example.
  • the outer package may include a housing 51 and a cover 53 .
  • the housing 51 may include a bottom plate and side plates connected to the bottom plate, and the bottom plate and the side plates enclose a receiving cavity.
  • the housing 51 has an opening communicating with the accommodation cavity, and the cover plate 53 can cover the opening to close the accommodation cavity.
  • the positive electrode piece, the negative electrode piece and the isolation film can be formed into the electrode assembly 52 through a winding process or a lamination process.
  • the electrode assembly 52 is packaged in the containing cavity.
  • the electrolyte soaks into the electrode assembly 52 .
  • the number of electrode assemblies 52 contained in the secondary battery 5 can be one or more, and those skilled in the art can select according to specific actual needs.
  • secondary batteries can be assembled into battery modules, and the number of secondary batteries contained in the battery module can be one or more. Those skilled in the art can select the specific number according to the application and capacity of the battery module.
  • FIG. 5 is a battery module 4 as an example.
  • a plurality of secondary batteries 5 may be arranged in sequence along the length direction of the battery module 4 .
  • the plurality of secondary batteries 5 can be fixed by fasteners.
  • the battery module 4 may further include a housing having a receiving space in which a plurality of secondary batteries 5 are received.
  • the above-mentioned battery modules can also be assembled into a battery pack.
  • the number of battery modules contained in the battery pack can be one or more. The specific number can be selected by those skilled in the art according to the application and capacity of the battery pack.
  • the battery pack 1 may include a battery box and a plurality of battery modules 4 disposed in the battery box.
  • the battery box includes an upper box 2 and a lower box 3 .
  • the upper box 2 can be covered with the lower box 3 and form a closed space for accommodating the battery module 4 .
  • Multiple battery modules 4 can be arranged in the battery box in any manner.
  • the present application also provides an electrical device, which includes at least one of the secondary battery, battery module, or battery pack provided by the present application.
  • the secondary battery, battery module, or battery pack may be used as a power source for the electrical device, or may be used as an energy storage unit for the electrical device.
  • the electric device may include mobile devices (such as mobile phones, laptops, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, and electric golf carts). , electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc., but are not limited to these.
  • a secondary battery, a battery module or a battery pack can be selected according to its usage requirements.
  • Figure 8 is an electrical device as an example.
  • the electric device is a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, etc.
  • a battery pack or battery module can be used.
  • the device may be a mobile phone, a tablet, a laptop, etc.
  • the device is usually required to be thin and light, and a secondary battery can be used as a power source.
  • the spinel lithium nickel manganate material of Example 1 was prepared according to the following steps S1 to S3.
  • Step S1 Put lithium carbonate (lithium salt), 3.5 ⁇ nickel manganese hydroxide (nickel manganese hydroxide precursor) and niobium oxide (M-containing compound) into an inclined mixer (mixer) Mix to obtain a mixed material, in which the molar ratio of Li/(Ni+Mn) is ensured to be within the range of 0.53:1, (Ni+Mn) is the total metal mole number of nickel and manganese, and the doping amount of Nb is based on Li /M molar ratio is calculated as 1:0.004.
  • Step S2 The mixed material obtained in step S1 is heated for the first time to 1000°C at a heating rate of 1°C/min in an oxygen-rich atmosphere with an oxygen content of 95% and a furnace pressure of 0.03Mpa for 30 hours. , after the first sintering is completed, it is naturally cooled to room temperature, and then ball milled to obtain powder.
  • Step S3 The powder obtained in Step S2 is again sintered in an oxygen-rich atmosphere with an oxygen content of 95% and a furnace pressure of 0.03Mpa at a heating rate of 1°C/min to 700°C for the second time. 10h, after the second sintering is completed, it is kept at this temperature for 10h, then naturally cooled to room temperature, and then ball milled to obtain spinel lithium nickel manganate material.
  • the stoichiometric formula of the spinel lithium nickel manganate material is Li(Ni 0.5 Mn 1.5 ) 0.996 M 0.004 O 4 , and the spinel lithium nickel manganate material obtained in Example 1 appears near 43.7°
  • the diffraction peaks and the diffraction peaks appearing near 18.8° are shown in Figure 9a, Figure 9b, and Figure 9c. From this, the peak area of the diffraction peak appearing near 43.7° and the peak area of the diffraction peak appearing near 18.8° are obtained. area, thus deducing (A(43.7°)/A(18.8°)) 1/2 of the spinel lithium nickel manganate material obtained in Example 1, which is within the scope of the present invention.
  • Example 1 the specific conditions during the preparation process of Example 1, as well as the specific stoichiometric formula, crystal structure, physical and chemical data, and electrical properties of the prepared spinel lithium nickel manganate material are shown in Table 1 and Table 2 respectively. .
  • Example 2 the same preparation method as in Example 1 is used, except that the specific conditions in the preparation process are changed respectively, as shown in Table 1, and the prepared spinel lithium nickel manganate material has The specific stoichiometric formula, crystal structure, physical and chemical data, electrical properties, etc. are also shown in Table 1 and Table 2 respectively.
  • Comparative Examples 1 to 12 the same preparation method as in Example 1 was used, except that the specific conditions in the preparation process were changed, as shown in Table 1, and the prepared spinel lithium nickel manganate material had The specific stoichiometric formula, crystal structure, physical and chemical data, electrical properties, etc. are also shown in Table 1 and Table 2 respectively.
  • the spinel lithium nickel manganate material obtained in Comparative Example 1 has a diffraction peak near 43.7° and a diffraction peak near 18.8°, as shown in Figure 10a, Figure 10b, and Figure 10c. From this, it is obtained that at 43.7 The peak area of the diffraction peak appearing near ° and the peak area of the diffraction peak appearing near 18.8° were thus calculated to be (A(43.7°)/A(18.8°) of the spinel lithium nickel manganate material obtained in Comparative Example 1. )) 1/2 , outside the scope of the present invention.
  • Equipment model Bruker X-ray diffractometer D8DISCOVER, refer to the standard procedure: JIS/K0131-1996 General Principles of X-ray Diffraction Analysis Method.
  • the specific process is: (1) Sample preparation: 1mm deep, 25mm diameter sample tank, sample preparation using flat plate sample preparation method; (2) Test: starting angle 15°, ending angle 70°, step length 0.01671°, each step length 0.24s ; (3) Fixed core parameters: voltage: 40KV, current: 40mA, anti-scatter slit: 1mm, according to the above specific processes (1) to (3), the results obtained from Examples 1 to 12 and Comparative Examples 1 to 12 Spinel lithium nickel manganate material was measured.
  • A(43.7°) i.e., the peak area of the diffraction peak appearing near 43.7° in the XRD pattern
  • A(18.8°) i.e., the The peak area of the diffraction peak appearing near 18.8° in the XRD pattern
  • Equipment model Malvern 3000 (MasterSizer 3000) laser particle size analyzer, refer to the standard process: GB/T19077-2016/ISO 13320:2009, specific test process: take an appropriate amount of the sample to be tested (the sample concentration ensures 8 to 12% opacity) ), add 20ml of deionized water, and at the same time superheat for 5 minutes (53KHz/120W) to ensure that the sample is completely dispersed, and then compare the results of Examples 1 to 12 and Comparative Examples 1 to 12 in accordance with the GB/T19077-2016/ISO 13320:2009 standard. The spinel lithium nickel manganate material was measured. The measurement results are shown in Table 2.
  • the spinel lithium nickel manganese oxide material obtained in Examples 1 to 12 and Comparative Examples 1 to 12 was used with the American Mc multi-station fully automatic specific surface area and pore analyzer Gemini VII 2390, and a sample of about 7g was taken and put into 9cc In a long tube with a bulb, degas at 150°C for 15 minutes, and then put it into the host computer to test and obtain BET data.
  • the measurement results are shown in Table 2.
  • the spinel lithium nickel manganate material prepared in each of Examples 1 to 12 and Comparative Examples 1 to 12 was used as the positive electrode active material, mixed with conductive carbon black and PVDF in a weight ratio of 90:5:5, and an appropriate amount of N-methyl was added Pyrrolidone, stir evenly to obtain positive electrode slurry. Coat the positive electrode slurry on the aluminum foil, dry it after coating, and obtain the positive electrode piece.
  • the loading amount of the positive active material on the positive electrode sheet is 0.015g/cm 2 .
  • a mixed solution of carbonate ester, phosphate ester, etc. containing 1 mol/L LiPF 6 was used as the electrolyte.
  • a polypropylene film ( ⁇ 16mm) with a thickness of 12 ⁇ m is used as the isolation film, and the lithium sheet, isolation film, and positive electrode sheet are placed in order, so that the isolation film is between the metal lithium sheet and the composite negative electrode sheet to play an isolation role. Inject the electrolyte, assemble it into a CR2030 button cell, and leave it for 24 hours to obtain a button half cell.
  • the button half-cell prepared using the spinel lithium nickel manganate material prepared in Examples 1 to 12 and Comparative Examples 1 to 12 as the positive active material was charged with a constant current of 0.1C until the voltage was 4.95 V, then charge at a constant voltage of 4.95V until the current is 0.05C. After leaving it for 5 minutes, discharge the button half cell at a constant current of 0.1C until the voltage is 3.5V.
  • the spinel lithium nickel manganese oxide material prepared in each of Examples 1 to 12 and Comparative Examples 1 to 12 was used as the positive electrode active material, mixed with conductive carbon black and PVDF in a weight ratio of 96:2.5:1.5, and an appropriate amount of N-methyl was added. base pyrrolidone, stir evenly to obtain positive electrode slurry. Coat the positive electrode slurry on the aluminum foil, dry it after coating, and obtain the positive electrode piece.
  • the loading amount of the positive active material on the positive electrode sheet is 0.02g/cm 2 .
  • a mixed solution of carbonate ester, phosphate ester, etc. containing 1 mol/L LiPF 6 was used as the electrolyte.
  • isolation film Using a polypropylene film ( ⁇ 16mm) with a thickness of 12 ⁇ m as the isolation film, place the positive electrode sheet, isolation film, and negative electrode sheet prepared above in order, so that the isolation film is between the positive and negative electrode sheets to play an isolation role, and roll Winding into shape and packed in aluminum plastic bags.
  • the electrolyte is injected, and the capacity is formed after encapsulation to prepare a graphite soft pack battery.
  • the graphite soft pack battery prepared by using the spinel lithium nickel manganate material prepared in each of Examples 1 to 12 and Comparative Examples 1 to 12 as the positive active material was used as the test object.
  • the graphite soft pack battery prepared by using the spinel lithium nickel manganate material prepared in each of Examples 1 to 12 and Comparative Examples 1 to 12 as the positive active material was used as the test object.
  • the graphite soft pack battery prepared by using the spinel lithium nickel manganate material prepared in each of Examples 1 to 12 and Comparative Examples 1 to 12 as the positive active material was used as the test object.
  • the graphite soft pack battery prepared by using the spinel lithium nickel manganate material prepared in each of Examples 1 to 12 and Comparative Examples 1 to 12 as the positive active material was used as the test object.
  • Examples 1, 2, 3 and Comparative Examples 1 and 2 that too large a doping amount will greatly affect the full capacitance and deduction capacity of the material, and affect its cycle to a certain extent, while too small a doping amount will greatly affect the full capacitance and buckle capacity of the material.
  • a large amount of doping affects its structural stability and reduces its role in passivating the octahedron, leading to an increase in side reactions, which is reflected in the reduction of its storage and cycle performance.
  • the second sintering process is a process to compensate for oxygen defects.
  • the effect of the second sintering temperature and annealing temperature that is too low is extremely low, while the annealing temperature that is too high will The second roasting temperature of the chicken will increase its oxygen deficiency.
  • Figures 11a and 11b show the Zr-doped lithium nickel manganate material of Comparative Example 11
  • Figures 12a and 12b show The lithium nickel manganate material is undoped. It can be seen that even if the lithium nickel manganate material is doped, it is doped with other elements (for example, Zr) outside the scope of the present invention, and it still cannot function. To passivate the octahedron and promote the growth of primary particles.
  • the spinel lithium nickel manganate material of the present application has low oxygen defect content, strong crystal structure stability, and low rock salt phase content. Furthermore, the secondary battery using the spinel lithium nickel manganate material has high energy density and long cycle life, and the gas production problem during the cycle is effectively suppressed.

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Abstract

本发明提供一种尖晶石镍锰酸锂材料，其中，所述尖晶石镍锰酸锂材料的XRD图谱中满足的条件为：0＜(A(43.7°)/A(18.8°))1/2≤0.2。通过本发明的尖晶石镍锰酸锂材料能够降低氧缺陷、增强晶体结构稳定性、并且降低岩盐相含量。

Description

尖晶石镍锰酸锂材料及其制备方法 技术领域
本发明涉及电化学领域，尤其涉及尖晶石镍锰酸锂材料及其制备方法。
背景技术
尖晶石镍锰酸锂的放电电压平台高达4.7V(vs Li/Li +)，理论放电比容量较高(147mAh/g)，因此具有较高的理论比能量密度(690Wh/kg)。当前实际用于石墨负极全电池中的尖晶石镍锰酸锂比能量密度也高于590Wh/kg，远高于磷酸铁锂(≤460Wh/kg)，与三元镍钴锰(≥650Wh/kg)接近，并且，尖晶石镍锰酸锂还有很大提升空间。尖晶石镍锰酸锂中Li、Ni含量均显著低于三元镍钴锰，且制备工艺简单，所以当用于石墨负极全电池时，电池的单位瓦时成本远低于三元镍钴锰，与磷酸铁锂接近。进而，尖晶石镍锰酸锂的热稳定性高、可允许的过充过放幅度大，因此，使用尖晶石镍锰酸锂体系的安全性明显优于使用三元镍钴锰体系。
综上，尖晶石镍锰酸锂具有高能量密度、低成本和高安全性，因此是十分具有潜力的低成本高能量密度正极材料。
但是，该材料本身存在如下缺陷而严重影响其在电芯中的应用：
高温条件下合成尖晶石镍锰酸锂易造成材料的氧缺失，从而造成大量氧缺陷及岩盐相，导致材料的结构稳定性降低，进而造成循环性能变差。
并且，在高温高压工作条件下尖晶石镍锰酸锂中的Mn 3+易发生歧化反应，Mn 2+溶解于电解液中并在负极沉积，同时材料表面和电解质之间发生大量副反应，导致电池性能整体恶化。
因此，现在研究的重点是降低尖晶石镍锰酸锂的氧缺陷、增强晶体结构稳定性、并且降低岩盐相含量，从而提升该正极材料的倍率性能、循环性能以及存储性能，由此提高使用该正极材料的电池的能量密度以及长循环寿命。
发明内容
本申请是鉴于上述技术问题而进行的，其目的在于，提供一种尖晶石镍锰酸锂材料及其制备方法、具备该尖晶石镍锰酸锂材料的二次电池、以及电池模块、电池包和用电装置，本申请的尖晶石镍锰酸锂材料能够降低氧缺陷、增强晶体结构稳定性、并且降低岩盐相含量。
为了实现上述目的，本申请第一方面在于提供一种尖晶石镍锰酸锂材料，其中，
所述尖晶石镍锰酸锂材料的XRD图谱中满足的条件为：0＜(A(43.7°)/A(18.8°)) 1/2≤0.2，优选为满足的条件为：0＜(A(43.7°)/A(18.8°)) 1/2≤0.1，
其中，A(43.7°)代表所述XRD图谱中在43.7°附近出现的衍射峰的峰面积，A(18.8°)代表所述XRD图谱中在18.8°附近出现的衍射峰的峰面积。
通过确立尖晶石镍锰酸锂材料的XRD图谱中(A(43.7°)/A(18.8°)) 1/2的特定范围与氧缺陷的关系，从而通过测定尖晶石镍锰酸锂材料的XRD图谱即可确定尖晶石镍锰酸锂材料的氧缺陷的下降。
在一些实施方式中，所述尖晶石镍锰酸锂材料的化学计量式为Li x(Ni 0.5Mn 1.5) nM mO 4，其中，M为选自W、P、B、Nb、Mo和Ta中的1种以上的元素，作为化学计量数，n+m＝1，x＝0.95～1.1，m＝0.001～0.015。通过对尖晶石镍锰酸锂掺杂选自W、P、B、Nb、Mo和Ta中的1种以上的元素达到上述化学计量范围，从而确保得到的尖晶石镍锰酸锂材料的晶体结构满足上述(A(43.7°)/A(18.8°)) 1/2在特定范围内的条件，由此确定晶体结构中氧缺陷的减少。
在一些实施方式中，所述尖晶石镍锰酸锂材料为单晶且边角钝化的八面体。通过以特定量掺杂上述元素对尖晶石镍锰酸锂进行修饰，使得得到的尖晶石镍锰酸锂材料形成边角钝化的八面体的单晶形貌，其中，钝化的边角能降低尖晶石镍锰酸锂的表面活性及减少与电解液的接触面积，从而减少副反应；单晶形貌则能有效减少冷压及电芯使用过程中出现开裂现象，提高电芯的整体性能。
在一些实施方式中，所述尖晶石镍锰酸锂材料的体积分布平均粒径Dv50为5μm～15μm，优选为5μm～10μm。通过设定本发明的镍锰尖 晶石材料的体积分布平均粒径Dv50在上述范围内，由于一次颗粒的粒径较大，因此能有效减少镍锰尖晶石材料与电解液的副反应。
在一些实施方式中，所述尖晶石镍锰酸锂材料的颗粒体积分布径距(Dv90-Dv10)/Dv50为1.0以下。通过设定本发明的镍锰尖晶石材料的(Dv90-Dv10)/Dv50在上述范围内，由于颗粒一致性较好，因此能有效减少镍锰尖晶石材料与电解液的副反应。
在一些实施方式中，所述镍锰尖晶石材料的BET为0.3m 2/g～1.0m 2/g，优选为0.3m 2/g～0.5m 2/g。通过设定本发明的镍锰尖晶石材料的BET在上述范围内，由于BET较小，因此能有效减少镍锰尖晶石材料与电解液的副反应。
本申请第二方面在于提供第一方面所涉及的尖晶石镍锰酸锂材料的制备方法，其中，
所述制备方法包括以下步骤S1～S3，
S1：将锂盐、镍锰氢氧化物前驱体与含M化合物放入混料机中进行混合，得到混合物料；
S2：将S1中得到的混合物料在富氧气氛中升温进行第一次烧结，第一次烧结结束后自然冷却至室温，接着进行球磨，得到粉体；
S3：将S2中得到的粉体再次在富氧气氛中升温进行第二次烧结，第二次烧结结束后保温，然后自然冷却至室温，接着进行球磨，得到尖晶石镍锰酸锂材料。
通过上述制备方法得到的发明的尖晶石镍锰酸锂材料具有较少的氧缺陷、副反应及Mn溶出，具有优良的综合电化学性能。
在一些实施方式中，在步骤S1中，锂盐与镍锰氢氧化物的混合比例按Li/(Ni+Mn)摩尔比计为(0.45～0.55):1，其中，(Ni+Mn)为镍、锰总金属摩尔数，并且，含M化合物的掺杂量按Li/M摩尔比计为1:(0.001～0.01)，优选为按Li/M摩尔比计为1:(0.003～0.007)。通过设定含M化合物的掺杂量在上述范围内，以及设定锂盐与镍锰氢氧化物的混合比在上述范围内，从而能够有效调控尖晶石镍锰酸锂材料的晶体形貌，有效降低氧缺陷、以及尖晶石镍锰酸锂材料与电解液的副反应，提高尖晶石镍锰酸锂材料的结构稳定性，降低Mn溶出。
在一些实施方式中，在步骤S1中，混料机为犁刀混、高混机或斜 试混料机。通过使用这些混料机，能够有效提高混合效率。
在一些实施方式中，在步骤S2和步骤S3中，第一次烧结和第二次烧结时的升温速率为5℃/min以下，优选为3℃/min以下。由于升温速率影响材料在结晶过程中的受热情况，因此通过设定升温速率在上述范围内，从而确保一次颗粒更加均匀。
在一些实施方式中，在步骤S2中，第一次烧结温度为500℃～1200℃，优选为600℃～1200℃，在步骤S3中，第二次烧结温度为400℃～700℃，优选为500℃～700℃。通过两次烧结，尖晶石镍锰酸锂材料的第二次烧结退火能弥补第一次烧结退火过程中的氧缺陷，进一步降低材料的氧缺陷，同时有效减少材料中Mn 3+的含量，降低Mn溶出。由于用选自W、P、B、Nb、Mo和Ta中的1种以上的元素对尖晶石镍锰酸锂进行掺杂，因此能够使得第一次烧结温度以及第二次烧结温度分别在上述较低的温度范围内进行合成。
在一些实施方式中，在步骤S2和步骤S3中，作为富氧气氛，氧含量大于60％，优选为80％～100％。通过设定富氧气氛在上述范围内，从而能够有效降低尖晶石镍锰酸锂材料中小颗粒的含量，同时降低尖晶石镍锰酸锂材料的氧缺陷含量。
在一些实施方式中，在步骤S2和步骤S3中，烧结炉内压力相对大气压为0.02MPa～0.08MPa，优选为0.02MPa～0.04MPa。通过设定烧结炉内压力相对大气压在上述范围内，从而能够有效降低尖晶石镍锰酸锂材料中小颗粒的含量，同时降低尖晶石镍锰酸锂材料的氧缺陷含量。
在一些实施方式中，在步骤S3中，保温时间为5h～40h，优选为15h～30h。通过设定保温时间在上述范围内，从而能够进一步降低材料的氧缺陷，同时有效减少材料中Mn 3+的含量降低Mn溶出。
本申请第三方面在于提供一种二次电池，该二次电池包括根据本申请第一方面所述的尖晶石镍锰酸锂材料。
本申请第四方面在于提供一种电池模块，该电池模块包括根据本申请第三方面所述的二次电池。
本申请第五方面在于提供一种电池包，该电池包包括根据本申请第四方面所述的电池模块。
本申请第六方面在于提供一种用电装置，该用电装置包括根据本申请第三方面所述的二次电池、根据本申请第四方面所述的电池模块和根据本申请第五方面所述的电池包中的至少一种。
根据本发明的尖晶石镍锰酸锂材料，作为正极材料，所述尖晶石镍锰酸锂材料的氧缺陷含量低，晶体结构稳定性强，岩盐相含量低，进而，使用该正极材料的二次电池具有高能量密度以及长循环寿命，并且，循环过程中的产气问题得到有效抑制。
附图说明
图1a、图1b、图1c是本申请一个实施方式的尖晶石镍锰酸锂材料的XRD图谱。
图2a、图2b是本申请另一个实施方式的尖晶石镍锰酸锂材料的颗粒的SEM图。
图3是本申请一个实施方式的二次电池的示意图。
图4是图3所示的本申请一个实施方式的二次电池的分解图。
图5是本申请一个实施方式的电池模块的示意图。
图6是本申请一个实施方式的电池包的示意图。
图7是图6所示的本申请一个实施方式的电池包的分解图。
图8是本申请一个实施方式的二次电池用作电源的用电装置的示意图。
图9a、图9b、图9c是本申请实施例1的尖晶石镍锰酸锂材料的XRD图谱。
图10a、图10b、图10c是本申请对比例1的尖晶石镍锰酸锂材料的XRD图谱。
图11a、图11b是本申请对比例11的掺杂有Zr的尖晶石镍锰酸锂材料的SEM图。
图12a、图12b是未进行掺杂的尖晶石镍锰酸锂材料的SEM图。
附图标记说明：
1电池包；2上箱体；3下箱体；4电池模块；5二次电池；51壳体；52电极组件；53顶盖组件
具体实施方式
以下，适当地参照附图详细说明具体公开了本申请的正极极片、二次电池、电池模块、电池包和电学装置的实施方式。但是会有省略不必要的详细说明的情况。例如，有省略对已众所周知的事项的详细说明、实际相同结构的重复说明的情况。这是为了避免以下的说明不必要地变得冗长，便于本领域技术人员的理解。此外，附图及以下说明是为了本领域技术人员充分理解本申请而提供的，并不旨在限定权利要求书所记载的主题。
本申请所公开的“范围”以下限和上限的形式来限定，给定范围是通过选定一个下限和一个上限进行限定的，选定的下限和上限限定了特别范围的边界。这种方式进行限定的范围可以是包括端值或不包括端值的，并且可以进行任意地组合，即任何下限可以与任何上限组合形成一个范围。例如，如果针对特定参数列出了60～120和80～110的范围，理解为60～110和80～120的范围也是预料到的。此外，如果列出的最小范围值1和2，和如果列出了最大范围值3、4和5，则下面的范围可全部预料到：1～3、1～4、1～5、2～3、2～4和2～5。在本申请中，除非有其它说明，数值范围“a～b”表示a到b之间的任意实数组合的缩略表示，其中a和b都是实数。例如数值范围“0～5”表示本文中已经全部列出了“0～5”之间的全部实数，“0～5”只是这些数值组合的缩略表示。另外，当表述某个参数为≥2的整数，则相当于公开了该参数为例如整数2、3、4、5、6、7、8、9、10、11、12等。
如果没有特别的说明，本申请的所有实施方式以及可选实施方式可以相互组合形成新的技术方案。
如果没有特别的说明，本申请的所有技术特征以及可选技术特征可以相互组合形成新的技术方案。
如果没有特别的说明，本申请所提到的“包括”和“包含”表示开放式，也可以是封闭式。例如，所述“包括”和“包含”可以表示还可以包括或包含没有列出的其它组分，也可以仅包括或包含列出的组分。
如果没有特别的说明，在本申请中，术语“或”是包括性的。举例来说，短语“A或B”表示“A，B，或A和B两者”。更具体地，以下任一条件均满足条件“A或B”：A为真(或存在)并且B为假(或不存 在)；A为假(或不存在)而B为真(或存在)；或A和B都为真(或存在)。
尖晶石镍锰酸锂材料
本申请的尖晶石镍锰酸锂材料的XRD图谱中满足的条件为：0＜(A(43.7°)/A(18.8°)) 1/2≤0.2，优选为满足的条件为：0＜(A(43.7°)/A(18.8°)) 1/2≤0.1，其中，A(43.7°)代表所述XRD图谱中在43.7°附近出现的衍射峰的峰面积，A(18.8°)代表所述XRD图谱中在18.8°附近出现的衍射峰的峰面积。
如图1a、图1b、图1c所示，本发明的尖晶石镍锰酸锂材料在43.7°附近出现衍射峰，并且，在18.8°附近出现衍射峰，由此可以得到在43.7°附近出现的衍射峰的峰面积以及在18.8°附近出现的衍射峰的峰面积，进而，推算出本发明的尖晶石镍锰酸锂材料的(A(43.7°)/A(18.8°)) 1/2。
当对尖晶石镍锰酸锂(LiNi 0.5Mn 1.5O 4)加热到一定温度以上时，LiNi 0.5Mn 1.5O 4会损失氧气，并歧化为尖晶石和Li xNi 1-xO，反应如下：LiNi 0.5Mn 1.5O 4→αLi xNi 1- xO+βLiNi 0.5+yMn 1.5O 4+γO 2，Li xNi 1-xO属于岩盐相，其在XRD图谱中2θ＝37.6、43.7°和63.5°会有一段峰表现，由该化学式可知，岩盐相越多，缺氧越多，由此氧缺陷越大，因此XRD图谱中2θ＝37.6°、43.7°和63.5°的衍射峰表现可表示为氧缺陷含量，其中37.6°及63.5°的衍射峰强极低，因此用43.7°来定义氧缺陷含量。另外，用18.8°来定义基准峰。
并且，本申请的尖晶石镍锰酸锂材料的化学计量式为Li x(Ni 0.5Mn 1.5) nM mO 4，其中，M为选自W、P、B、Nb、Mo和Ta中的1种以上的元素，作为化学计量数，n+m＝1，x＝0.95～1.1，m＝0.001～0.015。
从W、P、B、Nb、Mo和Ta中选择的1种以上的元素作为掺杂元素使得合成温度降低，上述反应减少，从而减少其氧缺陷；在上述化学计量式内，控制适当的掺杂量，如果过低的掺杂量则效果低，而过高的掺杂量则会影响尖晶石镍锰酸锂材料的容量发挥。
掺杂元素M可有效影响颗粒形貌使得其完美八面体的边角出现钝化，如图2a、图2b所示，证明本发明的尖晶石镍锰酸锂材料为单晶且边角钝化的八面体的形貌特征。
进而，本申请的尖晶石镍锰酸锂材料的体积分布平均粒径Dv50为 5μm～15μm，优选为5μm～10μm。Dv50的大小主要影响的材料与电解液的接触面，从而影响材料与电解液的副反应，但是Dv50的大小受到第一次烧结温度以及第二次烧结温度的影响。随着温度的升高DV50随之增大，因此较大的Dv50需要在较高的温度下才能合成，但温度升高其氧缺陷也会随之增加，因此限制Dv50不能过大，而Dv50过小又会导致较大的副反应而导致电性能恶化。
进而，所述尖晶石镍锰酸锂材料的颗粒体积分布径距(Dv90-Dv10)/Dv50为1.0以下。颗粒体积分布径距(Dv90-Dv10)/Dv50代表的是材料中各个颗粒之间的大小差异，差异越小其值越小。并且，其值主要还影响材料与电解液的副反应。
进而，所述镍锰尖晶石材料的BET为0.3m 2/g～1.0m 2/g，优选为0.3m 2/g～0.5m 2/g。BET主要影响尖晶石镍锰酸锂材料的容量发挥与副反应，较大的BET会提供较高的容量但其发生的副反应会增加，因此限制BET不能过大或过小。进而，BET对尖晶石镍锰酸锂材料的包覆也会产生影响。
尖晶石镍锰酸锂材料的制备方法
本发明的所述制备方法包括以下步骤S1～S3，
S1：将锂盐、镍锰氢氧化物前驱体与含M化合物放入混料机中进行混合，得到混合物料；
S2：将S1中得到的混合物料在富氧气氛中升温进行第一次烧结，第一次烧结结束后自然冷却至室温，接着进行球磨，得到粉体；
S3：将S2中得到的粉体再次在富氧气氛中升温进行第二次烧结，第二次烧结结束后保温，然后自然冷却至室温，接着进行球磨，得到尖晶石镍锰酸锂材料。
通过上述制备方法得到的发明的尖晶石镍锰酸锂材料具有较少的氧缺陷、副反应及Mn溶出，具有优良的综合电化学性能。
在本申请发明的制备方法的步骤S1中，锂盐与镍锰氢氧化物的混合比例按Li/(Ni+Mn)摩尔比计为(0.45～0.55):1，其中，(Ni+Mn)为镍、锰总金属摩尔数，并且，含M化合物的掺杂量按Li/M摩尔比计为1:(0.001～0.01)，优选为按Li/M摩尔比计为1:(0.003～0.007)。
其中，作为锂盐，可以举出碳酸锂、氢氧化锂。作为镍锰氢氧化 物，可以举出Ni 0.5Mn 1.5(OH) 7。作为含M化合物，可以举出含M的氯化物、含M的碳酸盐、含M的硫酸盐等，即，W、P、B、Nb、Mo和Ta这些元素的氯化物、碳酸盐、硫酸盐。
进而，通过设定含M化合物的掺杂量在上述Li/M摩尔比范围内，以及设定锂盐与镍锰氢氧化物的混合比在上述Li/(Ni+Mn)摩尔比的范围内，从而使得掺杂元素M进入晶格中会占据过渡金属的位置及空位，能有效减少材料中的过渡金属Mn的溶出已经材料结构的稳定性，两者是正向相关的，但过多的M掺杂量会较大的影响材料的电性能，过少则无法体现效果。
同时，选用的掺杂元素能有效增加一次颗粒的增长，使得材料可以在较低的温度下完成第二次烧结，较低的第二次烧结温度可有效减少氧缺陷的存在。
在本申请发明的制备方法的步骤S1中，混料机可以使用本领域常用的混料机，具体可以举出：犁刀混、高混机或斜试混料机。
在一些实施方式中，在步骤S2和步骤S3中，烧结时的升温速率为5℃/min以下，优选为3℃/min以下。升温速率的控制可以使得各个颗粒在生长过程中受热会更加均一，从而导致体积分布径距(Dv90-Dv10)/Dv50更小，Dv50主要和掺杂元素和第一次初烧温度相关。
在一些实施方式中，在步骤S2中，第一次烧结温度为500℃～1200℃，优选为600℃～1200℃，并且，在步骤S3中，第二次烧结温度为400℃～700℃，优选为500℃～700℃。其中，步骤S2的第一次烧结是尖晶石镍锰酸锂材料的结晶过程，所的的尖晶石镍锰酸锂材料的形貌、Dv50、电性能基本在步骤S2中定型，但在第一次烧结过程中温度较高会导致氧缺陷的增加。进而，步骤S3的第二次烧结是尖晶石镍锰酸锂材料的退火过程，能够弥补步骤S2的第一次烧结过程导致的氧缺陷，进一步提升尖晶石镍锰酸锂材料的性能。
在一些实施方式中，在步骤S2和步骤S3中，作为富氧气氛，氧含量大于60％，优选为80％～100％。由于富氧条件会影响材料的氧缺陷含量，因此需要控制氧含量在上述范围内。
在一些实施方式中，在步骤S2和步骤S3中，烧结炉内压力相对 大气压为0.02MPa～0.08MPa，优选为0.02MPa～0.04MPa。过大或过小的炉内压力会导致材料产生大量的小颗粒，从而导致Dv50偏小，颗粒体积分布径距(Dv90-Dv10)/Dv50偏大，并且气流交换受到影响导致氧缺陷含量增大。
在一些实施方式中，在步骤S3中，保温时间为5h～40h，优选为15h～30h。第二次烧结温度与保温时间相关，在步骤S3的范围内进行第二次烧结能有效降低尖晶石镍锰酸锂材料的氧缺陷及Mn 3+的含量，Mn 3+发生歧化反应导致尖晶石镍锰酸锂材料出现Mn溶出，因此Mn 3+含量的降低能有效降低Mn溶出。
在不影响本发明的效果的范围内，在步骤S3中，还可以加入本领域常用的有机物和/或无机物进行包覆，从而减少尖晶石镍锰酸锂材料在用于二次电池时与电解液发生副反应。
另外，以下适当参照附图对本申请的二次电池、电池模块、电池包和用电装置进行说明。
二次电池
本申请的一个实施方式中，提供一种二次电池。
通常情况下，二次电池包括正极极片、负极极片、电解质和隔离膜。在电池充放电过程中，活性离子在正极极片和负极极片之间往返嵌入和脱出。电解质在正极极片和负极极片之间起到传导离子的作用。隔离膜设置在正极极片和负极极片之间，主要起到防止正负极短路的作用，同时可以使离子通过。
[正极极片]
正极极片包括正极集流体以及设置在正极集流体至少一个表面的正极膜层，所述正极膜层包括本申请第一方面的尖晶石镍锰酸锂材料作为正极活性材料。
作为示例，正极集流体具有在其自身厚度方向相对的两个表面，正极膜层设置在正极集流体相对的两个表面的其中任意一者或两者上。
在一些实施方式中，所述正极集流体可采用金属箔片或复合集流体。例如，作为金属箔片，可采用铝箔。复合集流体可包括高分子材料基层和形成于高分子材料基层至少一个表面上的金属层。复合集流 体可通过将金属材料(铝、铝合金、镍、镍合金、钛、钛合金、银及银合金等)形成在高分子材料基材(如聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)、聚乙烯(PE)等的基材)上而形成。
在一些实施方式中，除了包含本申请第一方面的尖晶石镍锰酸锂材料之外，还可以包括其它正极活性材料。这些正极活性材料可采用本领域公知的用于电池的正极活性材料。作为示例，正极活性材料可包括以下材料中的至少一种：橄榄石结构的含锂磷酸盐、锂过渡金属氧化物及其各自的改性化合物。但本申请并不限定于这些材料，还可以使用其它可被用作电池正极活性材料的传统材料。这些正极活性材料可以仅单独使用一种，也可以将两种以上组合使用。其中，锂过渡金属氧化物的示例可包括但不限于锂钴氧化物(如LiCoO 2)、锂镍氧化物(如LiNiO 2)、锂锰氧化物(如LiMnO 2、LiMn 2O 4)、锂镍钴氧化物、锂锰钴氧化物、锂镍锰氧化物、锂镍钴锰氧化物(如LiNi 1/3Co 1/3Mn 1/3O 2(也可以简称为NCM 333)、LiNi 0.5Co 0.2Mn 0.3O 2(也可以简称为NCM 523)、LiNi 0.5Co 0.25Mn 0.25O 2(也可以简称为NCM 211)、LiNi 0.6Co 0.2Mn 0.2O 2(也可以简称为NCM 622)、LiNi 0.8Co 0.1Mn 0.1O 2(也可以简称为NCM 811)、锂镍钴铝氧化物(如LiNi 0.85Co 0.15Al 0.05O 2)及其改性化合物等中的至少一种。橄榄石结构的含锂磷酸盐的示例可包括但不限于磷酸铁锂(如LiFePO 4(也可以简称为LFP))、磷酸铁锂与碳的复合材料、磷酸锰锂(如LiMnPO 4)、磷酸锰锂与碳的复合材料、磷酸锰铁锂、磷酸锰铁锂与碳的复合材料中的至少一种。
在一些实施方式中，正极膜层还可选地包括粘结剂。作为示例，所述粘结剂可以包括聚偏氟乙烯(PVDF)、聚四氟乙烯(PTFE)、偏氟乙烯-四氟乙烯-丙烯三元共聚物、偏氟乙烯-六氟丙烯-四氟乙烯三元共聚物、四氟乙烯-六氟丙烯共聚物及含氟丙烯酸酯树脂中的至少一种。
在一些实施方式中，正极膜层还可选地包括导电剂。作为示例，所述导电剂可以包括超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯及碳纳米纤维中的至少一种。
在一些实施方式中，可以通过以下方式制备正极极片：将上述用于制备正极极片的组分，例如正极活性材料、导电剂、粘结剂和任意 其它的组分分散于溶剂(例如N-甲基吡咯烷酮)中，形成正极浆料；将正极浆料涂覆在正极集流体上，经烘干、冷压等工序后，即可得到正极极片。
[负极极片]
负极极片包括负极集流体以及设置在负极集流体至少一个表面上的负极膜层，所述负极膜层包括负极活性材料。
作为示例，负极集流体具有在其自身厚度方向相对的两个表面，负极膜层设置在负极集流体相对的两个表面中的任意一者或两者上。
在一些实施方式中，所述负极集流体可采用金属箔片或复合集流体。例如，作为金属箔片，可以采用铜箔。复合集流体可包括高分子材料基层和形成于高分子材料基材至少一个表面上的金属层。复合集流体可通过将金属材料(铜、铜合金、镍、镍合金、钛、钛合金、银及银合金等)形成在高分子材料基材(如聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)、聚乙烯(PE)等的基材)上而形成。
在一些实施方式中，负极活性材料可采用本领域公知的用于电池的负极活性材料。作为示例，负极活性材料可包括以下材料中的至少一种：人造石墨、天然石墨、软炭、硬炭、硅基材料、锡基材料和钛酸锂等。所述硅基材料可选自单质硅、硅氧化合物、硅碳复合物、硅氮复合物以及硅合金中的至少一种。所述锡基材料可选自单质锡、锡氧化合物以及锡合金中的至少一种。但本申请并不限定于这些材料，还可以使用其它可被用作电池负极活性材料的传统材料。这些负极活性材料可以仅单独使用一种，也可以将两种以上组合使用。
在一些实施方式中，负极膜层还可选地包括粘结剂。所述粘结剂可选自丁苯橡胶(SBR)、聚丙烯酸(PAA)、聚丙烯酸钠(PAAS)、聚丙烯酰胺(PAM)、聚乙烯醇(PVA)、海藻酸钠(SA)、聚甲基丙烯酸(PMAA)及羧甲基壳聚糖(CMCS)中的至少一种。
在一些实施方式中，负极膜层还可选地包括导电剂。导电剂可选自超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯及碳纳米纤维中的至少一种。
在一些实施方式中，负极膜层还可选地包括其它助剂，例如增稠 剂(如羧甲基纤维素钠(CMC-Na))等。
在一些实施方式中，可以通过以下方式制备负极极片：将上述用于制备负极极片的组分，例如负极活性材料、导电剂、粘结剂和任意其它组分分散于溶剂(例如去离子水)中，形成负极浆料；将负极浆料涂覆在负极集流体上，经烘干、冷压等工序后，即可得到负极极片。
[电解质]
电解质在正极极片和负极极片之间起到传导离子的作用。本申请对电解质的种类没有具体的限制，可根据需求进行选择。例如，电解质可以是液态的、凝胶态的或全固态的。
在一些实施方式中，所述电解质采用电解液。所述电解液包括电解质盐和溶剂。
在一些实施方式中，电解质盐可选自六氟磷酸锂、四氟硼酸锂、高氯酸锂、六氟砷酸锂、双氟磺酰亚胺锂、双三氟甲磺酰亚胺锂、三氟甲磺酸锂、二氟磷酸锂、二氟草酸硼酸锂、二草酸硼酸锂、二氟二草酸磷酸锂及四氟草酸磷酸锂中的至少一种。
在一些实施方式中，溶剂可选自碳酸亚乙酯、碳酸亚丙酯、碳酸甲乙酯、碳酸二乙酯、碳酸二甲酯、碳酸二丙酯、碳酸甲丙酯、碳酸乙丙酯、碳酸亚丁酯、氟代碳酸亚乙酯、甲酸甲酯、乙酸甲酯、乙酸乙酯、乙酸丙酯、丙酸甲酯、丙酸乙酯、丙酸丙酯、丁酸甲酯、丁酸乙酯、1,4-丁内酯、环丁砜、二甲砜、甲乙砜及二乙砜中的至少一种。
在一些实施方式中，所述电解液还可选地包括添加剂。例如添加剂可以包括负极成膜添加剂、正极成膜添加剂，还可以包括能够改善电池某些性能的添加剂，例如改善电池过充性能的添加剂、改善电池高温或低温性能的添加剂等。
[隔离膜]
在一些实施方式中，二次电池中还包括隔离膜。本申请对隔离膜的种类没有特别的限制，可以选用任意公知的具有良好的化学稳定性和机械稳定性的多孔结构隔离膜。
在一些实施方式中，隔离膜的材质可选自玻璃纤维、无纺布、聚乙烯、聚丙烯及聚偏二氟乙烯中的至少一种。隔离膜可以是单层薄膜，也可以是多层复合薄膜，没有特别限制。在隔离膜为多层复合薄膜时， 各层的材料可以相同或不同，没有特别限制。
在一些实施方式中，正极极片、负极极片和隔离膜可通过卷绕工艺或叠片工艺制成电极组件。
在一些实施方式中，二次电池可包括外包装。该外包装可用于封装上述电极组件及电解质。
在一些实施方式中，二次电池的外包装可以是硬壳，例如硬塑料壳、铝壳、钢壳等。二次电池的外包装也可以是软包，例如袋式软包。软包的材质可以是塑料，作为塑料，可列举出聚丙烯、聚对苯二甲酸丁二醇酯以及聚丁二酸丁二醇酯等。
本申请对二次电池的形状没有特别的限制，其可以是圆柱形、方形或其它任意的形状。例如，图3是作为一个示例的方形结构的二次电池5。
在一些实施方式中，参照图4，外包装可包括壳体51和盖板53。其中，壳体51可包括底板和连接于底板上的侧板，底板和侧板围合形成容纳腔。壳体51具有与容纳腔连通的开口，盖板53能够盖设于所述开口，以封闭所述容纳腔。正极极片、负极极片和隔离膜可经卷绕工艺或叠片工艺形成电极组件52。电极组件52封装于所述容纳腔内。电解液浸润于电极组件52中。二次电池5所含电极组件52的数量可以为一个或多个，本领域技术人员可根据具体实际需求进行选择。
电池模块
在一些实施方式中，二次电池可以组装成电池模块，电池模块所含二次电池的数量可以为一个或多个，具体数量本领域技术人员可根据电池模块的应用和容量进行选择。
图5是作为一个示例的电池模块4。参照图5，在电池模块4中，多个二次电池5可以是沿电池模块4的长度方向依次排列设置。当然，也可以按照其它任意的方式进行排布。进一步可以通过紧固件将该多个二次电池5进行固定。
可选地，电池模块4还可以包括具有容纳空间的外壳，多个二次电池5容纳于该容纳空间。
电池包
在一些实施方式中，上述电池模块还可以组装成电池包，电池包 所含电池模块的数量可以为一个或多个，具体数量本领域技术人员可根据电池包的应用和容量进行选择。
图6和图7是作为一个示例的电池包1。参照图6和图7，在电池包1中可以包括电池箱和设置于电池箱中的多个电池模块4。电池箱包括上箱体2和下箱体3，上箱体2能够盖设于下箱体3，并形成用于容纳电池模块4的封闭空间。多个电池模块4可以按照任意的方式排布于电池箱中。
用电装置
另外，本申请还提供一种用电装置，所述用电装置包括本申请提供的二次电池、电池模块、或电池包中的至少一种。所述二次电池、电池模块、或电池包可以用作所述用电装置的电源，也可以用作所述用电装置的能量存储单元。所述用电装置可以包括移动设备(例如手机、笔记本电脑等)、电动车辆(例如纯电动车、混合动力电动车、插电式混合动力电动车、电动自行车、电动踏板车、电动高尔夫球车、电动卡车等)、电气列车、船舶及卫星、储能系统等，但不限于此。
作为所述用电装置，可以根据其使用需求来选择二次电池、电池模块或电池包。
图8是作为一个示例的用电装置。该用电装置为纯电动车、混合动力电动车、或插电式混合动力电动车等。为了满足该用电装置对二次电池的高功率和高能量密度的需求，可以采用电池包或电池模块。
作为另一个示例的装置可以是手机、平板电脑、笔记本电脑等。该装置通常要求轻薄化，可以采用二次电池作为电源。
实施例
以下，说明本申请的实施例。下面描述的实施例是示例性的，仅用于解释本申请，而不能理解为对本申请的限制。实施例中未注明具体技术或条件的，按照本领域内的文献所描述的技术或条件或者按照产品说明书进行。所用试剂或仪器未注明生产厂商者，均为可以通过市购获得的常规产品。
<实施例1>
按照以下步骤S1～S3制备实施例1的尖晶石镍锰酸锂材料。
步骤S1：将碳酸锂(锂盐)、作为3.5μ镍锰氢氧化物(镍锰氢氧化物前驱体)与氧化铌(含M化合物)的放入斜式混料机(混料机)中进行混合，得到混合物料，其中，确保Li/(Ni+Mn)摩尔比为0.53:1范围内，(Ni+Mn)为镍、锰总金属摩尔数，并且，Nb的掺杂量为按Li/M摩尔比计为1:0.004。
步骤S2：将步骤S1中得到的混合物料在氧含量为95％的富氧气氛中、在炉内压力为0.03Mpa下，以1℃/min的升温速率升温至1000℃进行第一次烧结30h，第一次烧结结束后自然冷却至室温，接着进行球磨，得到粉体。
步骤S3：将步骤S2中得到的粉体再次在氧含量为95％的富氧气氛中、在炉内压力为0.03Mpa下，以1℃/min的升温速率升温至700℃进行第二次烧结10h，第二次烧结结束后在该温度下保温10h，然后自然冷却至室温，接着进行球磨，得到尖晶石镍锰酸锂材料。
经确认，该尖晶石镍锰酸锂材料的化学计量式为Li(Ni 0.5Mn 1.5) 0.996M 0.004O 4，并且，实施例1得到的尖晶石镍锰酸锂材料在43.7°附近出现的衍射峰以及在18.8°附近出现的衍射峰，如图9a、图9b、图9c所示，由此得到在43.7°附近出现的衍射峰的峰面积以及在18.8°附近出现的衍射峰的峰面积，从而推算出实施例1得到的尖晶石镍锰酸锂材料的(A(43.7°)/A(18.8°)) 1/2，在本发明的范围之内。
此外，实施例1的制备过程中的具体条件、以及制备得到的尖晶石镍锰酸锂材料的具体的化学计量式、晶体结构、物化数据、电性能，分别在表1、表2中显示。
<实施例2～12>
在实施例2～12中，采用与实施例1相同的制备方法，区别在于分别变更制备过程中的具体条件，具体如表1所示，并且，制备得到的尖晶石镍锰酸锂材料的具体的化学计量式、晶体结构、物化数据、电性能等，也分别在表1、表2中显示。
<对比例1～12>
在对比例1～12中，采用与实施例1相同的制备方法，区别在于分 别变更制备过程中的具体条件，具体如表1所示，并且，制备得到的尖晶石镍锰酸锂材料的具体的化学计量式、晶体结构、物化数据、电性能等，也分别在表1、表2中显示。
并且，对比例1得到的尖晶石镍锰酸锂材料在43.7°附近出现的衍射峰以及在18.8°附近出现的衍射峰，如图10a、图10b、图10c所示，由此得到在43.7°附近出现的衍射峰的峰面积以及在18.8°附近出现的衍射峰的峰面积，从而推算出对比例1得到的尖晶石镍锰酸锂材料的(A(43.7°)/A(18.8°)) 1/2，在本发明的范围之外。
以下，对上述本申请的实施例1～12及对比例1～12的所涉及的相关参数测试过程进行详细描述。
一.尖晶石镍锰酸锂材料的XRD图谱
设备型号：布鲁克X射线衍射仪D8DISCOVER，参考标准流程：JIS/K0131-1996X射线衍射分析法通则。
具体流程为：(1)制样：深1mm、直径25mm样品槽，平板制样法制样；(2)测试：起始角度15°，终止角度70°，步长0.01671°，每步时长0.24s；(3)固定核心参数：电压：40KV，电流：40mA，防散射狭缝：1mm，按照上述具体流程(1)～(3)，对实施例1～12和对比例1～12所得到的尖晶石镍锰酸锂材料进行测定。
然后，将数据用X'Pert HighScore Plus进行处理得出A(43.7°)(即，所述XRD图谱中在43.7°附近出现的衍射峰的峰面积)以及A(18.8°)(即，所述XRD图谱中在18.8°附近出现的衍射峰的峰面积)，从而可以推算出(A(43.7°)/A(18.8°)) 1/2。
二.体积中值粒径(D50)测试
设备型号：马尔文3000(MasterSizer 3000)激光粒度仪，参考标准流程：GB/T19077-2016/ISO 13320:2009，具体测试流程：取待测样品适量(样品浓度保证8～12％遮光度即可)，加入20ml去离子水，同时外超5min(53KHz/120W)，确保样品完全分散，之后按照GB/T19077-2016/ISO 13320:2009标准对实施例1～12和对比例1～12所得到的尖晶石镍锰酸锂材料进行测定。测定结果示于表2中。
三.颗粒体积分布径距(Dv90-Dv10)/Dv50)推算
在进行上述体积中值粒径(D50)测试时，同时得到Dv90和Dv10，然后通过计算公式(Dv90-Dv10)/Dv50推算出该数值。测定结果示于表2中。
四.尖晶石镍锰酸锂材料的颗粒形貌测试
分别将实施例1～12和对比例1～12所得到的尖晶石镍锰酸锂材料用ZEISS sigma 300扫描电子显微镜进行测试，然后参照标准JY/T010-1996进行测试，对样品形貌进行观测。测定结果示于表2中。
五.比表面积(BET)测试
将实施例1～12和对比例1～12所得到的尖晶石镍锰酸锂材料用美国麦克多站式全自动比表面积与孔隙分析仪Gemini VII 2390，取约7g左右的样品放入9cc带球泡的长管中，150℃脱气15min，随后放入主机测试得到BET数据。测定结果示于表2中。
六.电池性能测试
将实施例1～12和对比例1～12所得到的尖晶石镍锰酸锂材料进行如下电池性能测试。测试结果示于表2中。
扣式半电池的组装
将各实施例1～12和对比例1～12制备获得的尖晶石镍锰酸锂材料作为正极活性材料与导电炭黑、PVDF按重量比90:5:5混合，加入适量N-甲基吡咯烷酮，搅拌均匀，获得正极浆料。将正极浆料涂布在铝箔上，涂布后烘干，获得正极极片。正极极片上正极活性材料的负载量为0.015g/cm 2。
以含有1mol/L LiPF 6的碳酸脂、磷酸酯等的混合溶液作为电解液。
以厚度12μm的聚丙烯薄膜(Φ16mm)作为隔离膜，将锂片、隔离膜、正极片按顺序放好，使隔离膜处于金属锂片与复合负极极片中间起到隔离的作用。注入电解液，组装成CR2030扣式电池，静置24h， 得扣式半电池。
(1)扣电放电容量
在25℃下，将以各实施例1～12和对比例1～12制备获得的尖晶石镍锰酸锂材料作为正极活性材料制备的扣式半电池以0.1C恒流充电至电压为4.95V，然后以4.95V恒压充电至电流为0.05C，静置5min之后，将扣式半电池以0.1C恒流放电至电压为3.5V。
石墨软包电池的制作
分别将各实施例1～12和对比例1～12制备获得的尖晶石镍锰酸锂材料作为正极活性材料与导电炭黑、PVDF按重量比96:2.5:1.5混合，加入适量N-甲基吡咯烷酮，搅拌均匀，获得正极浆料。将正极浆料涂布在铝箔上，涂布后烘干，获得正极极片。正极极片上正极活性材料的负载量为0.02g/cm 2。
将石墨与导电炭黑、羧甲基纤维素按重量比96:1:3混合，加入适量纯水，搅拌均匀，获得负极浆料。将负极浆料涂布在铜箔上，涂布后烘干，获得负极极片。负极极片上石墨的负载量为0.008g/cm 2。
以含有1mol/L LiPF 6的碳酸脂、磷酸酯等的混合溶液作为电解液。
以厚度12μm的聚丙烯薄膜(Φ16mm)作为隔离膜，将上述制得的正极极片、隔离膜，负极极片按顺序放好，使隔离膜处于正负极片中间起到隔离的作用，卷绕成型，用铝塑袋包装。注入电解液，封装后进行化成容量，制得石墨软包电池。
(2)软包25℃循环300cls/％
以各实施例1～12和对比例1～12制备获得的尖晶石镍锰酸锂材料作为正极活性材料制备的石墨软包电池为测试对象。
在25℃下，将石墨软包电池以0.3C恒流充电至电压为4.9V，然后以4.9V恒压充电至电流为0.05C，静置5min之后，将石墨软包电池以0.33C恒流放电至电压为3.5V，此为一个充放电循环过程，此次的放电容量为首次循环的放电容量。将全电池按上述方法进行300次循环充放电测试后，记录剩余可逆放电容量。
(3)软包45℃循环200cls/％
以各实施例1～12和对比例1～12制备获得的尖晶石镍锰酸锂材料作为正极活性材料制备的石墨软包电池为测试对象。
在45℃下，将石墨软包电池以0.3C恒流充电至电压为4.9V，然后以4.9V恒压充电至电流为0.05C，静置5min之后，将石墨软包电池以0.33C恒流放电至电压为3.5V，此为一个充放电循环过程，此次的放电容量为首次循环的放电容量。将全电池按上述方法进行200次循环充放电测试后，记录剩余可逆放电容量。
(4)软包45℃满充存储(d)
以各实施例1～12和对比例1～12制备获得的尖晶石镍锰酸锂材料作为正极活性材料制备的石墨软包电池为测试对象。
在25℃下，将石墨软包电池以0.3C恒流充电至电压为4.9V，然后以4.9V恒压充电至电流为0.05C。然后将软包电池在45℃下放置，每隔5d做一次放电流程后，再次满充并在45℃环境下继续存储。提取放电容量值，直至放电容量衰减为初始值的80％，则存储结束。满充后在45℃下存储的总时长即为高温满充存储时长。充放电流程与(5)的全电容量测试的充放电流程相同。
(5)全电容量
以各实施例1～12和对比例1～12制备获得的尖晶石镍锰酸锂材料作为正极活性材料制备的石墨软包电池为测试对象。
在25℃下，将石墨软包电池以0.3C恒流充电至电压为4.9V，然后以4.9V恒压充电至电流为0.05C，静置5min之后，将石墨软包电池以0.33C恒流放电至电压为3.5V，该放电容量即为软包的全电容量。
表1
Figure PCTCN2022088926-appb-000001
表2
Figure PCTCN2022088926-appb-000002
从表1和表2可以看出：
由实施例1、2、3及对比例1、2可以看出，过大的掺杂量会较大的影响材料的全电容量及扣电容量，并一定程度的影响其循环，而过小的掺杂量较大的影响其结构稳定性，并且使得其钝化八面体的作用降低，导致副反应增加，体现在其存储及循环性能的降低。
由实施例1、4及对比例1、3可以看出，过大的升温速率会使得颗粒大小的一致性变低，即(Dv90-Dv10)/Dv50值变大，导致材料与电解液的副反应增加；同时过大的升温速率使得在颗粒生长过程中氧缺陷含量增加，其结构稳定性变差，从而使得存储及循环性能变差
由实施例1、5及对比例1、4可以看出，氧含量主要影响材料的氧缺陷含量，较低的氧含量会导致较大的氧缺陷含量，从而影响其存储及循环性能。
由实施例1、6、7及对比例1、5、6可以看出，炉内压力主要影响材料的(Dv90-Dv10)/Dv50值及BET的大小，过大或过小的炉内压力使得小颗粒增加而导致(Dv90-Dv10)/Dv50及BET过大，从而增加了材料的副反应。
由实施例1、8、9及对比例1、7、8可以看出，第二次烧结过程是弥补氧缺陷的过程，过低的第二次烧结温度退火温度其效果极低，而过高的第二次烧鸡温度反而会使得其氧缺陷增加。
由实施例1、10、11及对比例1、9、10可以看出，第二次烧结后的保温时间过短同样无法起到弥补氧缺陷的作用，而在范围外再延长保温时间并不会进一步降低氧缺陷，反而使得工艺成本增加。
由实施例1、12及对比例1、11、12可以看出除范围内的掺杂元素，其它元素无法起到钝化八面体及促进一次颗粒增长等效果，失去提高材料的结构稳定性，降低氧缺陷含量、副反应及过渡金属Mn溶出的效果。
进而，如图11a、图11b与图12a、图12b的对比来看，其中，图11a、图11b显示的是对比例11的掺杂有Zr的镍锰酸锂材料，图12a、图12b显示的是未进行掺杂的镍锰酸锂材料，可以看出，即使镍锰酸锂材料进行了掺杂，但是掺杂的是本发明范围之外的其它元素(例如，Zr)，依然无法起到钝化八面体及促进一次颗粒增长等效果。
综上所述，通过实施例1～12与对比例1～12对比可知，本申请的尖晶石镍锰酸锂材料的氧缺陷含量低，晶体结构稳定性强，岩盐相含量低，进而，使用该尖晶石镍锰酸锂材料的二次电池具有高能量密度以及长循环寿命，并且，循环过程中的产气问题得到有效抑制。
需要说明的是，本申请不限定于上述实施方式。上述实施方式仅为示例，在本申请的技术方案范围内具有与技术思想实质相同的构成、发挥相同作用效果的实施方式均包含在本申请的技术范围内。此外，在不脱离本申请主旨的范围内，对实施方式施加本领域技术人员能够想到的各种变形、将实施方式中的一部分构成要素加以组合而构筑的其它方式也包含在本申请的范围内。

Claims (23)

  1. 一种尖晶石镍锰酸锂材料，其中，
    所述尖晶石镍锰酸锂材料的XRD图谱中满足的条件为：0＜(A(43.7°)/A(18.8°)) 1/2≤0.2，
    其中，A(43.7°)代表所述XRD图谱中在43.7°附近出现的衍射峰的峰面积，A(18.8°)代表所述XRD图谱中在18.8°附近出现的衍射峰的峰面积。
  2. 根据权利要求1所述的尖晶石镍锰酸锂材料，其中，
    所述晶体结构满足的条件为：0＜(A(43.7°)/A(18.8°)) 1/2≤0.1。
  3. 根据权利要求1或2所述的尖晶石镍锰酸锂材料，其中，
    所述尖晶石镍锰酸锂材料的化学计量式为Li x(Ni 0.5Mn 1.5) nM mO 4，
    其中，M为选自W、P、B、Nb、Mo和Ta中的1种以上的元素，
    作为化学计量数，n+m＝1，x＝0.95～1.1，m＝0.001～0.015。
  4. 根据权利要求1～3中任一项所述的尖晶石镍锰酸锂材料，其中，
    所述尖晶石镍锰酸锂材料为单晶且边角钝化的八面体。
  5. 根据权利要求1～4中任一项所述的尖晶石镍锰酸锂材料，其中，
    所述尖晶石镍锰酸锂材料的体积分布平均粒径Dv50为5μm～15μm。
  6. 根据权利要求5所述的尖晶石镍锰酸锂材料，其中，
    所述尖晶石镍锰酸锂材料的体积分布平均粒径Dv50为5μm～10μm。
  7. 根据权利要求1～6中任一项所述的尖晶石镍锰酸锂材料，其中，
    所述尖晶石镍锰酸锂材料的颗粒体积分布径距(Dv90-Dv10)/Dv50为1.0以下。
  8. 根据权利要求1～7中任一项所述的尖晶石镍锰酸锂材料，其中，
    所述镍锰尖晶石材料的BET为0.3m 2/g～1.0m 2/g。
  9. 根据权利要求8所述的尖晶石镍锰酸锂材料，其中，
    所述镍锰尖晶石材料的BET为0.3m 2/g～0.5m 2/g。
  10. 一种权利要求1～9中任一项所述的尖晶石镍锰酸锂材料的制备方法，其中，
    所述制备方法包括以下步骤S1～S3，
    S1：将锂盐、镍锰氢氧化物前驱体与含M化合物放入混料机中进行混合，得到混合物料；
    S2：将S1中得到的混合物料在富氧气氛中升温进行第一次烧结，第一次烧结结束后自然冷却至室温，接着进行球磨，得到粉体；
    S3：将S2中得到的粉体再次在富氧气氛中升温进行第二次烧结，第二次烧结结束后保温，然后自然冷却至室温，接着进行球磨，得到尖晶石镍锰酸锂材料。
  11. 根据权利要求10所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S1中，锂盐与镍锰氢氧化物的混合比例按Li/(Ni+Mn)摩尔比计为(0.45～0.55):1，其中，(Ni+Mn)为镍、锰总金属摩尔数，
    并且，含M化合物的掺杂量按Li/M摩尔比计为1:(0.001～0.01)。
  12. 根据权利要求11所述的尖晶石镍锰酸锂材料的制备方法，其中，
    含M化合物的掺杂量按Li/M摩尔比计为1:(0.003～0.007)。
  13. 根据权利要求10～12中任一项所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S1中，混料机为犁刀混、高混机或斜试混料机。
  14. 根据权利要求10～13中任一项所述的尖晶石镍锰酸锂材料的制 备方法，其中，
    在步骤S2和步骤S3中，第一次烧结以及第二次烧结时的升温速率为5℃/min以下。
  15. 根据权利要求14所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S2和步骤S3中，第一次烧结以及第二次烧结时的升温速率为3℃/min以下。
  16. 根据权利要求10～15中任一项所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S2和步骤S3中，作为富氧气氛，氧含量大于60％。
  17. 根据权利要求16所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S2和步骤S3中，作为富氧气氛，氧含量为80％～100％。
  18. 根据权利要求10～17中任一项所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S2和步骤S3中，烧结炉内压力相对大气压为0.02MPa～0.08MPa。
  19. 根据权利要求18所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S2和步骤S3中，烧结炉内压力相对大气压为0.02MPa～0.04MPa。
  20. 根据权利要求10～19中任一项所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S2中，第一次烧结温度为500℃～1200℃，并且，在步骤S3中，第二次烧结温度为400℃～700℃。
  21. 根据权利要求19所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S2中，第一次烧结温度为600℃～1200℃，并且，在步骤S3中，第二次烧结温度为500℃～700℃。
  22. 根据权利要求10～21中任一项所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S3中，保温时间为5h～40h。
  23. 根据权利要求22所述的尖晶石镍锰酸锂材料的制备方法，其中，
    在步骤S3中，保温时间为15h～30h。
PCT/CN2022/088926 2022-04-25 2022-04-25 尖晶石镍锰酸锂材料及其制备方法 WO2023205993A1 (zh)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024099774A1 (en) * 2022-11-07 2024-05-16 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Method for producing spinel-type lithium-mixed transition metal oxide

Citations (3)

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Publication number Priority date Publication date Assignee Title
WO2016175312A1 (ja) * 2015-04-30 2016-11-03 三井金属鉱業株式会社 ５ｖ級スピネル型リチウムマンガン含有複合酸化物
WO2016175310A1 (ja) * 2015-04-30 2016-11-03 三井金属鉱業株式会社 ５ｖ級スピネル型リチウムマンガン含有複合酸化物の製造方法
CN113707875A (zh) * 2021-08-24 2021-11-26 蜂巢能源科技有限公司 一种尖晶石型镍锰酸锂、其制备方法和锂离子电池

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WO2016175312A1 (ja) * 2015-04-30 2016-11-03 三井金属鉱業株式会社 ５ｖ級スピネル型リチウムマンガン含有複合酸化物
WO2016175310A1 (ja) * 2015-04-30 2016-11-03 三井金属鉱業株式会社 ５ｖ級スピネル型リチウムマンガン含有複合酸化物の製造方法
CN113707875A (zh) * 2021-08-24 2021-11-26 蜂巢能源科技有限公司 一种尖晶石型镍锰酸锂、其制备方法和锂离子电池

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024099774A1 (en) * 2022-11-07 2024-05-16 L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude Method for producing spinel-type lithium-mixed transition metal oxide

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