WO2024222016A1 - 硫酸铁钠正极材料及其制备方法和应用 - Google Patents

硫酸铁钠正极材料及其制备方法和应用 Download PDF

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WO2024222016A1
WO2024222016A1 PCT/CN2023/142447 CN2023142447W WO2024222016A1 WO 2024222016 A1 WO2024222016 A1 WO 2024222016A1 CN 2023142447 W CN2023142447 W CN 2023142447W WO 2024222016 A1 WO2024222016 A1 WO 2024222016A1
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polyoxyethylene
sodium
positive electrode
sulfate
heating
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English (en)
French (fr)
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唐永炳
许欢
姚文娇
兰元其
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Shenzhen Institute of Advanced Technology of CAS
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Shenzhen Institute of Advanced Technology of CAS
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/054—Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/0471—Processes of manufacture in general involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the invention belongs to the technical field of new energy materials, and specifically relates to a sodium iron sulfate positive electrode material and a preparation method and application thereof.
  • sodium-ion batteries are expected to be used in low-speed electric vehicles, communication base stations, large-scale energy storage and other fields.
  • the advantage of sodium-ion batteries is that the crustal reserves of sodium resources are abundant (2.75%), which is more than 400 times that of lithium (0.0065%), and the global distribution is uniform and simple to refine.
  • the internal resistance of sodium-ion batteries is higher than that of lithium-ion batteries, the instantaneous heat generation in the case of short circuit is less, the temperature rise is lower, the thermal runaway temperature is higher than that of lithium batteries, and they have higher safety; the operating temperature range of sodium-ion batteries is wider (-40°C to 80°C), which is suitable for extremely cold and hot scenes; sodium-ion batteries have excellent fast charging capabilities, and the charging time only takes about 10 minutes; sodium-ion batteries can use aluminum foil as positive and negative current collectors, and the current collector cost is lower. Therefore, it is of great significance to develop efficient and low-cost sodium-ion battery technology.
  • positive electrode materials affect the cost, energy density, cycle life, etc. of sodium-ion batteries.
  • Positive electrode materials affect the energy density and power density of sodium-ion batteries by affecting their ability to accommodate sodium ions and the patency of transmission channels.
  • the stability and impurity composition of positive electrode materials will affect the life of the battery.
  • the mainstream sodium-ion positive electrode materials are divided into three categories: oxides, polyanionic compounds and Prussian blue analogs.
  • oxide positive electrode materials have a simple structure, high energy density, and moderate cycle performance; polyanionic positive electrode materials have a stable structure, low energy density, and the best cycle performance; Prussian blue analogs have an adjustable working voltage, good rate performance, and the cycle performance needs to be improved.
  • this material Due to the strong inductive effect of sulfate, this material exhibits the highest Fe 3+ /Fe 2+ redox potential among existing cathode materials, thus making up for the shortcoming of insufficient energy density to a certain extent, with a theoretical energy density of 540Wh/kg.
  • Some people have reported non-stoichiometric sodium ferric sulfate, which has expanded the scope of exploration of this system.
  • the three-dimensional skeleton structure of sodium ferric sulfate can remain stable during the migration of sodium ions, so the cycle performance is good.
  • One of the key problems of sodium ferric sulfate is its sensitivity to air.
  • the present invention aims to solve at least one of the technical problems existing in the prior art.
  • the present invention proposes a sodium iron sulfate positive electrode material, by introducing amphiphilic molecules with a moderate hydrophilic-hydrophobic balance (HLB) value during the preparation process, so that the surface of the prepared sodium iron sulfate particles is uniformly coated with a layer of amphiphilic molecules, wherein the hydrophilic end of the amphiphilic molecules points to the sodium iron sulfate, and the hydrophobic end points to the outside, thereby isolating the sodium iron sulfate particles from the air and protecting the sodium iron sulfate.
  • the sodium iron sulfate positive electrode material provided by the present invention can be left in the air for a long time, and the electrochemical performance after being left for 12 months has no obvious decline.
  • the second aspect of the present invention provides a method for preparing the above-mentioned sodium iron sulfate positive electrode material.
  • the third aspect of the present invention provides an application of a positive electrode material in the preparation of a sodium ion battery.
  • a fourth aspect of the present invention provides an application of a sodium ion battery in the field of secondary batteries.
  • a sodium ferric sulfate positive electrode material comprising sodium ferric sulfate and amphiphilic molecules modifying the sodium ferric sulfate, wherein the hydrophilic ends of the amphiphilic molecules face the sodium ferric sulfate, and the hydrophobic ends of the amphiphilic molecules face away from the sodium ferric sulfate; and the HLB of the amphiphilic molecules is 10-16.
  • amphiphilic molecules with a moderate hydrophilic-hydrophobic balance are selected so that the surface of the sodium ferric sulfate particles is surrounded by amphiphilic molecules.
  • the hydrophilic end of the amphiphilic molecule points to the sodium ferric sulfate, and the hydrophobic end points to the outside, thereby isolating the sodium ferric sulfate particles from the air, effectively improving the stability of the sodium ferric sulfate in the air.
  • the sodium ferric sulfate positive electrode material of the present invention can be stably placed in an air environment for 12 months without obvious attenuation of electrochemical performance.
  • the HLB of the amphiphilic molecule is 13-15.
  • the amphiphilic molecule includes polyoxypropylene (5PO) lanolin ether, polyoxyethylene (5EO) sorbitan monooleate, polyoxyethylene cetyl ether, polyoxyethylene (20EO) sorbitan tristearate, polyoxyethylene lauryl ether, polyoxyethylene (20EO) sorbitan trioleate, polyoxyethylene oxypropylene oleate, polyoxyethylene lanolin derivatives, polyoxyethylene monooleate, polyoxyethylene monooleate, polyoxyethylene monopalmitate, polyoxyethylene monostearate, polyoxyethylene (10EO) oleyl alcohol ether, polyoxyethylene monolaurate, polyoxyethylene alkylphenol, polyoxyethylene (10EO) Acetylated lanolin derivatives, polyoxyethylene sorbitol lanolin derivatives, polyoxyethylene alkyl aryl ethers, polyoxyethylene monolaurate, polyoxyethylene lauryl ether, polyoxyethylene castor oil, polyoxyethylene vegetable oil, polyoxyethylene (4
  • the amphiphilic molecule further comprises mixed fatty acid polyoxyethylene ester and resin acid polyoxyethylene ester.
  • the amphiphilic molecule includes at least one of polyoxyethylene (10EO) acetylated lanolin derivatives, polyoxyethylene sorbitol lanolin derivatives, polyoxyethylene alkyl aryl ethers, polyoxyethylene monolaurate, polyoxyethylene lauryl ether, polyoxyethylene castor oil, polyoxyethylene vegetable oil, polyoxyethylene (4EO) sorbitan monolaurate, cholesterol ether, lanolin ether, polyoxyethylene sorbitan monolaurate, polyoxyethylene (20EO) sorbitan monostearate, polyoxyethylene (20EO) sorbitan monostearate, polyoxyethylene (20EO) oleyl ether, polyoxyethylene (20EO) methyl glucoside sesquioleate, polyoxyethylene (16EO) lanolin ether, polyoxyethylene (20EO) sorbitan monooleate and polyoxyethylene monostearate.
  • polyoxyethylene (10EO) acetylated lanolin derivatives polyoxyethylene sorbitol lanolin derivatives, poly
  • a method for preparing a positive electrode material comprises:
  • the raw material for preparing the sodium ferric sulfate, the amphiphilic molecule, the non-polar organic solvent and the polar solvent are mixed and heated to remove impurities;
  • the mixed heating includes a first heating and a second heating performed sequentially;
  • the temperature of the first heating is 50 to 100° C.; the time of the first heating is 1 to 12 hours;
  • the temperature of the second heating is 120-250° C.; the time of the second heating is 1-12 hours.
  • the first low-temperature heating and heat preservation can promote the uniformity of the system, thereby providing favorable conditions for the second high-temperature coating and improving the air stability of the positive electrode material.
  • the second heating and heat preservation promote the formation of sodium iron sulfate positive electrode material.
  • the effective combination of polar solvents and non-polar solvents can promote the amphiphilic molecules to form a uniform protective layer on the surface of the sodium ferric sulfate sample, with the hydrophilic end facing the sodium ferric sulfate and the hydrophobic end facing away from the sodium ferric sulfate.
  • the temperature of the first heating is 70-90° C.; and the time of the first heating is 1-3 hours.
  • the temperature of the second heating is 170-190° C.; and the time of the second heating is 3-5 hours.
  • the temperature of the first heating is 80° C.; and the time of the first heating is 2 hours.
  • the temperature of the second heating is 180° C.; and the time of the second heating is 4 hours.
  • the impurity removal step includes cooling, solid-liquid separation, washing, and drying to obtain the target product.
  • a method for preparing the positive electrode material comprises:
  • step S2 placing the mixed solution in step S1 into a stainless steel reactor lined with polytetrafluoroethylene and heating it;
  • the invention provides a preparation method with simple preparation steps, low energy consumption, good product uniformity and high yield.
  • the polar solvent includes at least one of water, formamide, acetone, trifluoroacetic acid, ethanol, chloroform, ether, acetic acid, acetonitrile, isopropanol, methanol, dimethyl sulfoxide, acetonitrile, N,N-dimethylformamide, hexamethylphosphoramide, pyridine, tetramethylethylenediamine, triethylamine, n-butanol, dioxane, tetrahydrofuran and methyl formate.
  • the non-polar solvent includes at least one of benzene, carbon tetrachloride, hexane, isooctane, dichloromethane, cyclohexane, petroleum ether and pentane.
  • the raw materials for preparing the sodium ferric sulfate include sodium sulfate and ferrous sulfate hydrate.
  • the ferrous sulfate hydrate includes at least one of ferrous sulfate monohydrate, ferrous sulfate pentahydrate and ferrous sulfate heptahydrate.
  • the ratio of the polar solvent, the non-polar solvent, the amphiphilic molecule, the sodium sulfate and the ferrous sulfate hydrate is 1-20:1-20:10-500:5-6.75:10-13.5, wherein the polar solvent and the non-polar solvent are calculated by volume liters, the amphiphilic molecule is calculated by mass grams, and the sodium sulfate and the ferrous sulfate hydrate are calculated by molar amount of substance.
  • the ratio of the polar solvent, the non-polar solvent, the amphiphilic molecule, the sodium sulfate and the ferrous sulfate hydrate is 10-20:10-20:100-500:5-6.75:10-13.5, wherein the polar solvent and the non-polar solvent are calculated by volume liter, the amphiphilic molecule is calculated by mass gram, and the sodium sulfate and the ferrous sulfate hydrate are calculated by molar amount of substance.
  • the ratio of the polar solvent, the non-polar solvent, the amphiphilic molecule, the sodium sulfate and the ferrous sulfate hydrate is 10:10:100:6:12, wherein the polar solvent and the non-polar solvent are calculated by volume liters, the amphiphilic molecule is calculated by mass grams, and the sodium sulfate and the ferrous sulfate hydrate are calculated by molar amount of substance.
  • a positive electrode material is used in a sodium ion battery.
  • the method for preparing a sodium ion battery comprises:
  • A1 Mix the sodium iron sulfate positive electrode material, conductive agent and binder in a mass ratio of 8:1:1, grind thoroughly and add appropriate amount of N-methylpyrrolidone to form a uniform slurry; use a scraper to apply the slurry on the surface of aluminum foil with a thickness of 200 ⁇ m, vacuum dry and cut into discs with a diameter of 10mm, compact and set aside as positive electrode sheets.
  • A2 In an inert gas-protected glove box, press the sodium metal into thin sheets, cut them into 12 mm diameter discs, and keep them for batteries. Negative pole spare.
  • A3 Cut the commercial fiberglass film into discs with a diameter of 16 mm and set aside as a diaphragm.
  • the conductive agent includes: at least one of conductive carbon black, Ketjen black, super P, conductive carbon balls, conductive graphite, carbon nanotubes, carbon fibers and graphene.
  • the binder includes at least one of polyvinylidene fluoride, polytetrafluoroethylene, polyvinyl alcohol, carboxymethyl cellulose, SBR rubber, and polyolefin.
  • the hydrophobic end of the amphiphilic molecule can well connect the cathode and the organic solvent in the electrolyte, thereby increasing the wettability between the cathode and the electrolyte, and providing an effective path for the rapid conduction of sodium ions.
  • the solution provided by the present invention has a simple process and low energy consumption; the prepared sodium iron sulfate cathode has good air stability and good rate performance.
  • an application of a sodium ion battery in the field of secondary batteries is provided.
  • FIG1 is a schematic diagram of the structure of a sodium iron sulfate positive electrode material according to Example 1 of the present invention.
  • FIG2 is an XRD diagram of the sodium iron sulfate positive electrode material prepared in Example 1 (fresh sample), the sodium iron sulfate positive electrode material prepared in Example 1 after being placed in the air for 12 months (sample after being placed for 12 months), and standard ferrous sulfate;
  • Example 3 is a SEM image of the sodium iron sulfate positive electrode material prepared in Example 1 (fresh sample) and the sodium iron sulfate positive electrode material prepared in Example 1 after being placed in the air for 12 months (sample after being placed for 12 months);
  • FIG4 is a cycle capacity diagram of a battery prepared using (fresh sample) and (sample after 12 months of storage) of Example 1 as raw materials;
  • FIG. 5 is a charge-discharge curve of the 500th and 900th cycles of a battery prepared using the sample of Example 1 after being set aside for 12 months as raw material.
  • This embodiment discloses a sodium iron sulfate positive electrode material and a preparation method thereof, and the specific steps are:
  • Figure 2 is an XRD diagram of the fresh sample obtained in Example 1, the sample after being placed in the air for 12 months, and the standard ferrous sulfate.
  • the diffraction spectrum of the sample obtained in Example 1 matches the standard diffraction spectrum very well, and the XRD of the sample after being placed in the air for 12 months still matches the standard diffraction spectrum very well.
  • Figure 3 is a SEM image of the sample obtained in Example 1 and the sample after being placed in the air for 12 months. As can be seen from the figure, the sample still has a good morphology after being placed, and no deformation, surface roughening, precipitation of tiny particles, etc. are found in the particles;
  • Figure 4 is a cycle capacity diagram of the battery prepared using the (fresh sample) and (sample after 12 months of storage) of Example 1 as raw materials. As can be seen from the figure, both exhibit good cycle stability, and the long cycle performance of the sample after storage basically maintains the original level;
  • FIG5 is a charge-discharge curve of the 500th and 900th cycles of a battery prepared using the sample of Example 1 after being shelved for 12 months as raw material; as can be seen from the figure, the electrochemical reversibility and stability of the sample after shelving are good.
  • Example 2 to 8 Compared with Example 1, Examples 2 to 8 only changed the type of non-polar solvent. The specific experimental conditions are shown in Table 1.
  • Example 9 to 10 Compared with Example 1, Examples 9 to 10 only changed the volume of the non-polar solvent.
  • the specific experimental conditions are shown in Table 1.
  • Example 11 to 18 Compared with Example 1, Examples 11 to 18 only changed the type of polar solvent, and the specific experimental conditions are shown in Table 1.
  • Example 19 Compared with Example 1, Examples 19 to 20 only changed the volume of the polar solvent.
  • the specific experimental conditions are shown in Table 1.
  • Example 21 to 40 Compared with Example 1, Examples 21 to 40 only changed the types of amphiphilic molecules, and the specific experimental conditions are shown in Table 1.
  • Example 41 to 45 Compared with Example 1, Examples 41 to 45 only changed the mass of the amphiphilic molecules.
  • the specific experimental conditions are shown in Table 1.
  • Example 46 to 48 Compared with Example 1, Examples 46 to 48 only changed the amount of sodium sulfate substance. The specific experimental conditions are shown in Table 1.
  • Example 49 to 50 Compared with Example 1, Examples 49 to 50 only changed the type of ferrous sulfate hydrate, and the specific experimental conditions are shown in Table 1.
  • Example 51 to 53 Compared with Example 1, Examples 51 to 53 only changed the amount of ferrous sulfate heptahydrate.
  • the specific experimental conditions are shown in Table 1.
  • Example 1 Compared with Example 1, Examples 56 to 57 only changed t1.
  • the specific experimental conditions are shown in Table 1.
  • Example 1 Compared with Example 1, Examples 58 to 59 only changed T2. The specific experimental conditions are shown in Table 1.
  • Example 1 Compared with Example 1, Examples 60 to 61 only changed t2. The specific experimental conditions are shown in Table 1.
  • Examples 62 to 65 respectively used a mixed polar solvent, a mixed non-polar solvent, a mixed amphiphilic molecule and a mixed ferrous sulfate hydrate.
  • Example 66 to 67 comprehensively changed T1, t1, T2, and t2.
  • the specific experimental conditions are shown in Table 1.
  • This comparative example discloses a sodium iron sulfate positive electrode material and a preparation method thereof.
  • the difference between this comparative example and Example 1 is that the polyoxyethylene castor oil in Example 1 is not included, and other conditions are the same as those in Example 1.
  • This comparative example discloses a sodium iron sulfate positive electrode material and a preparation method thereof. The difference between this comparative example and Example 1 is that the distilled water in Example 1 is not included, and other conditions are the same as those in Example 1.
  • This comparative example discloses a sodium iron sulfate positive electrode material and a preparation method thereof. The difference between this comparative example and Example 1 is that the benzene in Example 1 is not included, and other conditions are the same as those in Example 1.
  • This comparative example discloses a sodium iron sulfate positive electrode material and a preparation method thereof.
  • the difference between this comparative example and Example 1 is that the temperature is directly raised to 180° C. instead of being kept at 80° C. for 2 hours.
  • Other conditions are the same as those in Example 1.
  • This comparative example discloses a sodium iron sulfate positive electrode material and a preparation method thereof.
  • the difference between this comparative example and Example 1 is that only a 2-hour heat preservation operation at 80° C. is performed, and the temperature is no longer raised to 180° C.
  • Other conditions are the same as those in Example 1.
  • This comparative example discloses a sodium iron sulfate positive electrode material and a preparation method thereof.
  • the difference between this comparative example and Example 1 is that tetraethylene glycol oleic acid (HLB value is 7.7) with an HLB of less than 10 as an amphiphilic molecule is introduced, and other conditions are the same as those in Example 1.
  • This comparative example discloses a sodium iron sulfate positive electrode material and a preparation method thereof.
  • the difference between this comparative example and Example 1 is that: Potassium oleate (HLB value is 20) with an amphiphilic molecule HLB greater than 16 was introduced, and other conditions were the same as those in Example 1.
  • Test Example 1 is to prepare a sodium ion battery using the sodium iron sulfate positive electrode materials of Comparative Examples 1 to 7 and Examples 1 to 67, and the preparation method comprises the following steps:
  • A1 Preparation of positive electrode: The positive electrode active materials of Examples 1 to 67 and Comparative Examples 1 to 7, conductive carbon (SuperP), and binder (polyvinylidene fluoride) were mixed in a mass ratio of 7.5:1.5:1, and after sufficient grinding, an appropriate amount of nitrogen methyl pyrrolidone was added to form a uniform slurry; the slurry was coated on the surface of aluminum foil with a scraper to a thickness of 2 ⁇ m, and after vacuum drying, it was cut into discs with a diameter of 10 mm, compacted, and reserved as positive electrode sheets for later use.
  • SuperP conductive carbon
  • binder polyvinylidene fluoride
  • A2 Preparation of negative electrode: In an inert gas-protected glove box, press metallic sodium into thin sheets, cut into 12 mm diameter discs, and reserve them for use as the negative electrode of the battery.
  • A3 Preparation of diaphragm: Cut commercial glass fiber film into discs with a diameter of 16 mm and set aside as diaphragm.
  • Performance test Sodium ion batteries prepared from sodium iron sulfate positive electrode materials of comparative examples 1 to 7 and embodiments 1 to 67 were tested.
  • the constant current charge and discharge test adopted the BTSDA test system of Shenzhen Xinwei Electronics Co., Ltd.
  • the environment was a constant temperature and humidity room (25°C, 35%), and the test voltage range was 2.0 to 4.5V.
  • the test results are shown in Table 2; wherein, the median voltage refers to the median voltage of the 100th cycle, and the capacity retention rate refers to the capacity retention rate of the 1000th cycle relative to the 11th cycle.
  • the test results are shown in Table 2.
  • the sodium ion batteries prepared from the sodium iron sulfate positive electrode materials of Examples 54 to 57 and Example 1 that when the heating temperature and the insulation time in the first stage are insufficient, the electrochemical performance and air stability of the samples are poor; preferably, the heating temperature in the first stage is 80°C and the insulation time is 2 hours.
  • the sodium ion batteries prepared from the sodium iron sulfate positive electrode materials of Examples 58 to 61 and Example 1 that when the second-stage heating temperature and the insulation time are insufficient, the electrochemical performance and air stability of the samples are poor; preferably, the second-stage heating temperature is 180°C and the insulation time is 4 hours.

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Abstract

硫酸铁钠正极材料及其制备方法和应用，正极材料包括硫酸铁钠和修饰硫酸铁钠的两亲分子，两亲分子的亲水端朝向所述硫酸铁钠，两亲分子的疏水端背向硫酸铁钠；两亲分子的HLB为10～16。通过在制备过程中引入亲水疏水平衡值(HLB)适中的两亲分子，使得制备的硫酸铁钠颗粒表面均匀包覆着一层两亲分子，从而隔离硫酸铁钠颗粒和空气的接触，保护硫酸铁钠。该硫酸铁钠可以长期搁置在空气中，搁置12个月后的电化学性能无明显衰退。

Description

硫酸铁钠正极材料及其制备方法和应用 技术领域
本发明属于新能源材料技术领域，具体涉及一种硫酸铁钠正极材料及其制备方法和应用。
背景技术
钠离子电池作为锂离子电池的补充，有望在低速电动车、通讯基站、大规模储能等领域应用。相对于锂离子电池，钠离子电池的优势在于钠资源的地壳储量丰富(2.75％)，是锂的400倍以上(0.0065％)，且全球分布均匀、提炼简单。此外，钠离子电池的内阻比锂离子电池高，在短路的情况下瞬时发热量少，温升较低，热失控温度高于锂电池，具备更高的安全性；钠离子电池的工作温度区间更宽(-40℃到80℃)，适用于极寒酷热的场景；钠离子电池的快充能力卓越，充电时间只需要10分钟左右；钠离子电池可以采用铝箔作为正负极集流体，集流体成本更低。因此，发展高效低成本钠离子电池技术具有重大意义。
正极材料作为钠离子电池的关键组份，影响了钠离子电池的成本、能量密度、循环寿命等。正极材料通过影响容纳钠离子的能力和传输通道的通畅性来影响钠离子电池的能量密度和功率密度，同时正极材料的稳定性、杂质成分会影响电池的寿命。目前主流的钠离子正极材料有氧化物、聚阴离子型化合物和普鲁士蓝类似物三大类。相较而言，氧化物正极材料的结构简单，能量密度较高，循环性能适中；聚阴离子型正极材料的结构稳定，能量密度较低，循环性能最好；普鲁士蓝类似物的工作电压可调、倍率性能较好、循环性能有待提升。硫酸铁钠(化学通式Na2+xFe2-y(SO4)3，x＝0-0.7，y＝0–0.35)是一种应用于钠离子电池的聚阴离子型正极材料，具有原材料地壳储量丰富、成本低、工作电压高、长循环性能好的优势，于2014年被报导，由于硫酸根的强诱导效应，该材料在已有正极材料中展现了最高的Fe3+/Fe2+氧化还原电位，从而在一定程度上弥补了能量密度不足的短板，理论能量密度达540Wh/kg。有人报导了非化学计量比的硫酸铁钠，扩展了该体系的探索范围。硫酸铁钠的三维骨架结构能在钠离子迁移过程中保持稳定，因此循环性能较好。硫酸铁钠现存的关键问题之一是对空气敏感。由于与空气中的水分和氧气相互作用，硫酸铁钠会出现表面残碱，同时部分亚铁离子被氧化，因而增加制浆和涂布难度，恶化比容量和循环性能。针对该问题，相关技术通过制备氮掺杂石墨烯包覆的硫酸铁钠正极，提升了材料的抗氧化能力，在空气中暴露一个月后检测到的Fe3+(14％)明显低于未包覆的材料(29％)。还有技术报导了还原氧化石墨烯包覆的硫酸铁钠正极，但并未提供材料对环境的稳定性。然而，已有研究中，大部分需要用到石墨烯类材料，成本较高；且流程 复杂。且已获得的材料大多仍含有三价铁，不利于电化学性能的发挥。
因此，解决目前硫酸铁钠正极材料出现的对空气的湿度和氧化气氛敏感等问题是当务之急。
发明内容
本发明旨在至少解决现有技术中存在的技术问题之一。为此，本发明提出一种硫酸铁钠正极材料，通过在制备过程中引入亲水疏水平衡值(HLB)适中的两亲分子，使得制备的硫酸铁钠颗粒表面均匀包覆着一层两亲分子，其中两亲分子的亲水端指向硫酸铁钠，且疏水端指向外侧，从而隔离硫酸铁钠颗粒和空气的接触，保护硫酸铁钠。本发明提供的硫酸铁钠正极材料可以长期搁置在空气中，搁置12个月后的电化学性能无明显衰退。
本发明的第二个方面提供了一种上述硫酸铁钠正极材料的制备方法。
本发明的第三个方面提供了一种正极材料在钠离子电池制备中的应用。
本发明的第四个方面提供了一种钠离子电池在二次电池领域的应用。
根据本发明的第一方面实施例的一种硫酸铁钠正极材料，所述正极材料包括硫酸铁钠和修饰所述硫酸铁钠的两亲分子，所述两亲分子的亲水端朝向所述硫酸铁钠，所述两亲分子的疏水端背向所述硫酸铁钠；所述两亲分子的HLB为10～16。
根据本发明实施例的一种硫酸铁钠正极材料，至少具有以下有益效果：
本发明的硫酸铁钠正极材料在制备过程中，通过选择亲水疏水平衡值(HLB)适中的两亲分子，使得硫酸铁钠颗粒表面被两亲分子包围。其中两亲分子的亲水端指向硫酸铁钠，疏水端指向外部，从而隔绝硫酸铁钠颗粒与空气的接触，有效提升了硫酸铁钠的在空气中的稳定性，本发明的硫酸铁钠正极材料，能够在空气环境中稳定放置12个月，电化学性能无明显衰减。
根据本发明的一些优选地实施例，所述两亲分子的HLB为13～15。
根据本发明的一些实施例，所述两亲分子包括聚氧丙烯(5PO)羊毛醇醚、聚氧乙烯(5EO)失水山梨醇单油酸酯、聚氧乙烯十六烷基醚、聚氧乙烯(20EO)失水山梨醇三硬脂酸酯、聚氧乙烯月桂醚、聚氧乙烯(20EO)失水山梨醇三油酸酯、聚氧乙烯氧丙烯油酸酯、聚氧乙烯羊毛脂衍生物、聚氧乙烯单油酸酯、聚氧乙烯单油酸酯、聚氧乙烯单棕榈酸酯、聚氧乙烯单硬脂酸酯、聚氧乙烯(10EO)油醇醚、聚氧乙烯单月桂酸酯、聚氧乙烯烷基酚、聚氧乙烯(10EO)乙酰化羊毛脂衍生物、聚氧乙烯山梨醇羊毛脂衍生物、聚氧乙烯烷基芳基醚、聚氧乙烯单月桂酸酯、聚氧乙烯月桂醚、聚氧乙烯蓖麻油、聚氧乙烯植物油、聚氧乙烯(4EO)失水山梨醇单月桂酸酯、胆固醇醚、羊毛醇醚、聚氧乙烯(20EO)失水山梨醇单硬脂酸酯、聚氧乙烯(20EO)油醇醚、聚氧乙烯(20EO)甲基葡萄糖苷倍半油酸酯、聚氧乙烯(16EO)羊毛醇醚、聚氧乙烯(20EO)失水山梨醇单油酸酯、聚氧乙烯单硬脂酸酯、聚氧乙烯单油酸酯、聚氧乙烯油基 醚、聚氧乙烯十八醇、聚氧乙烯油醇、聚氧乙烯脂肪醇、聚乙二醇单棕榈酸酯、聚氧乙烯(20EO)失水山梨醇单棕榈酸酯、聚氧乙烯十六烷基醇、聚氧乙烯氧丙烯硬脂酸酯和聚氧乙烯单硬脂酸酯中的至少一种。
根据本发明的一些实施例，所述两亲分子还包括混合脂肪酸聚氧乙烯酯和树脂酸聚氧乙烯酯。
根据本发明的一些优选地实施例，所述两亲分子包括聚氧乙烯(10EO)乙酰化羊毛脂衍生物、聚氧乙烯山梨醇羊毛脂衍生物、聚氧乙烯烷基芳基醚、聚氧乙烯单月桂酸酯、聚氧乙烯月桂醚、聚氧乙烯蓖麻油、聚氧乙烯植物油、聚氧乙烯(4EO)失水山梨醇单月桂酸酯、胆固醇醚、羊毛醇醚、聚氧乙烯失水山梨醇单月桂酸酯、聚氧乙烯(20EO)失水山梨醇单硬脂酸酯、聚氧乙烯(20EO)油醇醚、聚氧乙烯(20EO)甲基葡萄糖苷倍半油酸酯、聚氧乙烯(16EO)羊毛醇醚、聚氧乙烯(20EO)失水山梨醇单油酸酯和聚氧乙烯单硬脂酸酯中的至少一种。
根据本发明的第二方面实施例的一种所述的正极材料的制备方法，包括：
将所述硫酸铁钠的制备原料、所述两亲分子、非极性有机溶剂和极性溶剂混合加热后除杂；
所述混合加热包括依次进行的第一次加热和第二次加热；
所述第一次加热的温度为50～100℃；所述第一次加热的时间为1～12h；
所述第二次加热的温度为120～250℃；所述第二次加热的时间为1～12h。
根据本发明实施例的一种正极材料的制备方法，至少具有以下有益效果：
1、第一次的低温加热和保温能够促进体系的均匀性，从而为第二次加热的高温包覆提供了有利条件，提升了正极材料的空气稳定性，第二次加热和保温促进了形成硫酸铁钠正极材料。
2、极性溶剂和非极性溶剂的有效组合可以促进两亲分子在硫酸铁钠样品表面形成均匀的亲水端朝向硫酸铁钠，疏水端背向硫酸铁钠的保护层。
根据本发明的一些实施例，所述第一次加热的温度为70～90℃；所述第一次加热的时间为1～3h。
根据本发明的一些实施例，所述第二次加热的温度为170～190℃；所述第二次加热的时间为3～5h。
根据本发明的一些实施例，所述第一次加热的温度为80℃；所述第一次加热的时间为2h。
根据本发明的一些实施例，所述第二次加热的温度为180℃；所述第二次加热的时间为4h。
根据本发明的一些实施例，所述除杂的步骤包括降温后经过固液分离、洗涤、干燥后得到目标产物。
根据本发明的一些实施例，一种所述的正极材料的制备方法，包括：
S1：将所述硫酸铁钠的制备原料、所述两亲分子、非极性有机溶剂和极性溶剂混合后得到混合液；
S2：将步骤S1中的混合液置于聚四氟乙烯内衬的不锈钢反应釜，加热；
S3：加热后降温至常温，经过抽滤(固液分离)、无水酒精洗涤、自然晾干，得到目标产物。
本发明提供了的制备方法，制备步骤简单，能耗低，产品均一性良好，产率高。
根据本发明的一些实施例，所述极性溶剂包括水、甲酰胺、丙酮、三氟乙酸、乙醇、氯仿、乙醚、乙酸、乙腈、异丙醇、甲醇、二甲基亚砜、乙腈、N,N-二甲基甲酰胺、六甲基磷酰胺、吡啶、四甲基乙二胺、三乙胺、正丁醇、二氧六环、四氢呋喃和甲酸甲酯中的至少一种。
根据本发明的一些实施例，所述非极性溶剂包括苯、四氯化碳、己烷、异辛烷、二氯甲烷、环己烷、石油醚和戊烷中的至少一种。
根据本发明的一些实施例，所述硫酸铁钠的制备原料包括硫酸钠和硫酸亚铁水合物。
根据本发明的一些实施例，所述硫酸亚铁水合物包括一水合硫酸亚铁、五水合硫酸亚铁和七水合硫酸亚铁中的至少一种。
根据本发明的一些实施例，所述极性溶剂、所述非极性溶剂、所述两亲分子、所述硫酸钠和所述硫酸亚铁水合物的比为1～20:1～20:10～500:5～6.75:10～13.5，其中，极性溶剂和非极性溶剂以体积升计算，两亲分子以质量克计算，硫酸钠和硫酸亚铁水合物以物质的量摩尔计算。
根据本发明的一些优选地实施例，所述极性溶剂、所述非极性溶剂、所述两亲分子、所述硫酸钠和所述硫酸亚铁水合物的比为10～20:10～20:100～500:5～6.75:10～13.5，其中，极性溶剂和非极性溶剂以体积升计算，两亲分子以质量克计算，硫酸钠和硫酸亚铁水合物以物质的量摩尔计算。
根据本发明的一些优选地实施例，所述极性溶剂、所述非极性溶剂、所述两亲分子、所述硫酸钠和所述硫酸亚铁水合物的比为10:10:100:6:12，其中，极性溶剂和非极性溶剂以体积升计算，两亲分子以质量克计算，硫酸钠和硫酸亚铁水合物以物质的量摩尔计算。
根据本发明的第三方面实施例的一种正极材料在钠离子电池中的应用。
根据本发明的一些实施例，所述在钠离子电池的制备方法包括：
A1：将硫酸铁钠正极材料、导电剂、粘结剂以8:1:1的质量比混合，充分研磨后加入适量N-甲基吡咯烷酮，形成均匀浆料；用刮刀将浆料涂覆于铝箔表面，厚度200μm，真空干燥后裁切成直径10mm的圆片，压实，留作正极极片备用。
A2：在惰性气体保护的手套箱中将金属钠压成薄片，裁剪成12mm直径圆片，留作电池 负极备用。
A3：将商用玻璃纤维薄膜裁切成直径16mm的圆片，留作隔膜备用。
A4：在惰性气体保护的手套箱中，将上述制备好的电池正极、隔膜和电池负极依次紧密堆叠，滴加商用电解液(1.0M NaClO4 in EC:PC＝1:1Vol％)使隔膜完全浸润，然后将上述堆叠部分封装入扣式电池壳体，完成电池组装。
根据本发明的一些实施例，所述导电剂包括：导电炭黑、科琴黑、super P、导电碳球、导电石墨、碳钠米管、碳纤维和石墨烯中的至少一种。
根据本发明的一些实施例，所述粘结剂包括：偏聚氟乙烯、聚四氟乙烯、聚乙烯醇、羧甲基纤维素、SBR橡胶、聚烯烃中的至少一种。
本发明中制备的硫酸铁钠正极材料装成电池后，两亲分子的疏水端可以很好的连接正极和电解液中的有机溶剂，从而增加正极-电解液之间的浸润性，为钠离子的快速传导提供有效路径。相较于其它方法，本发明提供的方案流程简单，能耗低；所制备的硫酸铁钠正极空气稳定性好，倍率性能好。
根据本发明的第四方面实施例的一种钠离子电池在二次电池领域的应用。
本发明的其它特征和优点将在随后的说明书中阐述，并且，部分地从说明书中变得显而易见，或者通过实施本发明而了解。
附图说明
本发明的上述和/或附加的方面和优点从结合下面附图对实施例的描述中将变得明显和容易理解，其中：
图1是本发明实施例1硫酸铁钠正极材料的结构示意图；
图2是实施例1制备得到的硫酸铁钠正极材料(新鲜样品)、实施例1制备得到的硫酸铁钠正极材料在空气中搁置12个月后(搁置12个月后的样品)以及标准硫酸亚铁的XRD图；
图3是实施例1制备得到的硫酸铁钠正极材料(新鲜样品)、实施例1制备得到的硫酸铁钠正极材料在空气中搁置12个月后(搁置12个月后的样品)的SEM图；
图4是以实施例1的(新鲜样品)和(搁置12个月后的样品)为原料制备得到的电池的循环容量图；
图5是以实施例1搁置12个月后的样品为原料制备得到的电池第500圈和第900圈的充放电曲线。
具体实施方式
下面详细描述本发明的实施例，所述实施例的示例在附图中示出，其中自始至终相同或类 似的标号表示相同或类似的元件或具有相同或类似功能的元件。下面通过参考附图描述的实施例是示例性的，仅用于解释本发明，而不能理解为对本发明的限制。
实施例1
本实施例公开了一种硫酸铁钠正极材料及其制备方法，具体步骤为：
S1：取蒸馏水10升、苯10升、聚氧乙烯蓖麻油100克、硫酸钠6摩尔、七水合硫酸亚铁12摩尔，混合后得到混合液；
S2：将混合液置于40升聚四氟乙烯内衬的不锈钢反应釜，加热到80℃，保温2小时，随后加热到180℃，保温4小时；
S3：降温至常温，经过抽滤(固液分离)、无水酒精洗涤、自然晾干，得到目标产物。
图2为实施例1所得新鲜样品、在空气中搁置12个月后的样品以及标准硫酸亚铁的XRD图。从图中看出，实施例1所得样品的衍射谱与标准衍射谱匹配很好，且在空气中搁置12个月后的样品XRD仍然与标准衍射谱匹配良好。
图3为实施例1所得样品、样品在空气中搁置12个月后的SEM图。从图中看出，搁置后样品仍然形貌良好，颗粒未发现变形、表面变粗糙、微小颗粒析出等问题；
图4是以实施例1的(新鲜样品)和(搁置12个月后的样品)为原料制备得到的电池的循环容量图。从图中看出，二者均表现了良好的循环稳定性，搁置后样品的长循环性能基本维持原水平；
图5是以实施例1搁置12个月后的样品为原料制备得到的电池第500圈和第900圈的充放电曲线；从图中看出，搁置后样品的电化学可逆性和稳定性良好。
实施例2～8与实施例1相比，仅改变了非极性溶剂的种类，具体实验条件如表1所示。
实施例9～10与实施例1相比，仅改变了非极性溶剂的体积，具体实验条件如表1所示。
实施例11～18与实施例1相比，仅改变了极性溶剂的种类，具体实验条件如表1所示。
实施例19～20与实施例1相比，仅改变了极性溶剂的体积，具体实验条件如表1所示。
实施例21～40与实施例1相比，仅改变了两亲分子种类，具体实验条件如表1所示。
实施例41～45与实施例1相比，仅改变了两亲分子的质量，具体实验条件如表1所示。
实施例46～48与实施例1相比，仅改变了硫酸钠物质的量，具体实验条件如表1所示。
实施例49～50与实施例1相比，仅改变了硫酸亚铁水合物种类，具体实验条件如表1所示。
实施例51～53与实施例1相比，仅改变了七水合硫酸亚铁物质的量，具体实验条件如表1所示。
实施例54～55与实施例1相比，仅改变了T1，具体实验条件如表1所示。
实施例56～57与实施例1相比，仅改变了t1，具体实验条件如表1所示。
实施例58～59与实施例1相比，仅改变了T2，具体实验条件如表1所示。
实施例60～61与实施例1相比，仅改变了t2，具体实验条件如表1所示。
实施例62～65与实施例1相比，分别采用了混合极性溶剂、混合非极性溶剂、混合两亲分子和混合硫酸亚铁水合物。
实施例66～67与实施例1相比，综合改变了T1、t1、T2、t2，具体实验条件如表1所示。
表1实施例2～67的实验条件


对比例1
本对比例公开了一种硫酸铁钠正极材料及其制备方法，本对比例和实施例1的区别在于不包括实施例1中的聚氧乙烯蓖麻油，其他条件和实施例1相同。
对比例2
本对比例公开了一种硫酸铁钠正极材料及其制备方法，本对比例和实施例1的区别在于不包括实施例1中的蒸馏水，其他条件和实施例1相同。
对比例3
本对比例公开了一种硫酸铁钠正极材料及其制备方法，本对比例和实施例1的区别在于不包括实施例1中的苯，其他条件和实施例1相同。
对比例4
本对比例公开了一种硫酸铁钠正极材料及其制备方法，本对比例和实施例1的区别在于不进行80℃的2小时保温操作，直接升温到180℃，其他条件和实施例1相同。
对比例5
本对比例公开了一种硫酸铁钠正极材料及其制备方法，本对比例和实施例1的区别在于只进行80℃的2小时保温操作，不再升温到180℃，其他条件和实施例1相同。
对比例6
本对比例公开了一种硫酸铁钠正极材料及其制备方法，本对比例和实施例1的区别在于，引入两亲分子的HLB小于10的四乙二醇油酸(HLB值为7.7)，其他条件和实施例1相同。
对比例7
本对比例公开了一种硫酸铁钠正极材料及其制备方法，本对比例和实施例1的区别在于， 引入两亲分子的HLB大于16的油酸钾(HLB值为20)，其他条件和实施例1相同。
测试例1
测试例1为以对比例1～7和实施例1～67的硫酸铁钠正极材料制备得到钠离子电池，制备方法包含以下步骤：
A1：制备正极：分别将实施例1～67、对比例1～7的正极活性材料、导电碳(SuperP)、粘结剂(聚偏氟乙烯)以7.5:1.5:1的质量比混合，充分研磨后加入适量氮甲基吡咯烷酮，形成均匀浆料；用刮刀将浆料涂覆于铝箔表面，厚度2μm，真空干燥后裁切成直径10mm的圆片，压实，留作正极极片备用。
A2：制备负极：在惰性气体保护的手套箱中将金属钠压成薄片，裁剪成12mm直径圆片，留作电池负极备用。
A3：制备隔膜：将商用玻璃纤维薄膜裁切成直径16mm的圆片，留作隔膜备用。
A4：组装电池：在惰性气体保护的手套箱中，将上述制备好的电池正极、隔膜和电池负极依次紧密堆叠，滴加商用电解液(1.0M NaClO4 in EC:PC＝1:1Vol％)使隔膜完全浸润，然后将上述堆叠部分封装入扣式电池壳体，完成电池组装。
性能测试：对对比例1～7和实施例1～67的硫酸铁钠正极材料制备得到钠离子电池进行测试。其中恒流充放电测试采用深圳市新威电子股份有限公司的BTSDA测试系统，环境为恒温恒湿房(25℃，35％)，测试电压范围为2.0～4.5V。前十圈倍率采用0.1C，第十一圈开始倍率改为1C(1C＝120mAh/g)。测试结果如表2所示；其中，中值电压指第100圈的中值电压，容量保持率指第1000圈相对第11圈的容量保持率，测试结果如表2所示。
表2：钠离子电池的电化学测试结果


由表2可知：
实施例2～67与实施例1的硫酸铁钠正极材料制备得到钠离子电池制备得到的相比，得出不同制备条件对产物性能的影响规律总结如下：
由实施例2～8与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，非极性溶剂的种类对电池的电化学性能和空气稳定性影响不大；
由实施例9,10与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，所用非极性溶剂的体积占比过小时，正极材料和搁置12个月后的正极材料的比容量均有所降低，且搁置后比容量降低的更严重，说明非极性溶剂的体积太小不利于正极材料的生成，同时不利于正极材料在空气中保持稳定性；当非极性溶剂的体积占比达到一定值后，对正极材料的电化学性能及空气稳定性的影响不大。
由实施例11～18与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，极性溶剂的种类对产物的电化学性能和空气稳定性影响不大。
由实施例19,20与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，所用极性溶剂的体积占比太小时，正极材料和搁置12个月后的正极材料的比容量均有所降低，且搁置后比容量降低的更严重，说明极性溶剂的体积太小不利于正极材料的空气稳定性；体积占比达到一 定值后，对电化学性能及空气稳定性的影响不大。
由实施例21～40与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，HLB值不同的两亲分子对正极材料的电化学性能影响不大，但是对正极材料的空气稳定性影响较为显著。当采用HLB值在13-15之间的两亲分子(对应实施例21～29)时，搁置12小时后正极材料的首圈比容量、中值电压和容量保持率均更高，说明样品的空气稳定性更优。
由实施例41～45与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，两亲分子的用量影响产物的空气稳定性。两亲分子的用量太少时(实施例41,42)，搁置12个月后的正极材料的电化学性能变差，说明正极材料的空气稳定性不足；两亲分子的量足够时(实施例1、43～45)，样品的空气稳定性良好；优选每摩尔硫酸钠使用100/6克的两亲分子。
由实施例46～53与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，硫酸钠物质的量、硫酸亚铁水合物、硫酸亚铁水合物物质的量对产物电化学性能及空气稳定性的影响不大。
由实施例54～57与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，第一阶段加热温度和保温时间不足时，样品的电化学性能和空气稳定性欠佳；优选第一阶段加热温度为80℃和保温时间2小时。
由实施例58～61与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，第二阶段加热温度和保温时间不足时，样品的电化学性能和空气稳定性欠佳；优选第二阶段加热温度为180℃和保温时间4小时。
由实施例62～65与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，加入混合极性溶剂、混合非极性溶剂、混合两亲分子和混合硫酸亚铁水合物对产物的电化学性能和空气稳定性的影响不大。
由实施例66～67与实施例1的硫酸铁钠正极材料制备得到钠离子电池可知，第一加热阶段的时间不能太短，第二阶段的加热温度不能太低，否则样品的电化学性能和空气稳定性将欠佳。
实施例2～67与对比例1～7相比，得出以下结论：
实施例2～67与对比例1的对比结果表明，当不采用两亲分子时，初始样品的电化学性能相当，但搁置12个月后的样品电化学性能显著衰退，说明两亲分子对样品的空气稳定性起到良好的保护作用。
实施例2～67与对比例2～3的对比结果表明，当不添加极性溶剂或者非极性溶剂时，初始电池的电化学性能相当，但搁置12个月后的样品电化学性能显著衰退，对比例2～3容量保持率略优于对比例1；推测可能原因是极性溶剂和非极性溶剂的有效组合可以促进两亲分子在硫酸铁钠样品表面形成两亲分子的亲水端朝向所述硫酸铁钠，两亲分子的疏水端背向硫酸铁钠的 均匀保护层。
实施例2～67与对比例4的对比结果表明，第一阶段的低温加热和保温能够提高样品的空气稳定性；推测可能原因是第一阶段的低温加热和保温能够促进体系的均匀性，从而为高温包覆提供有利条件。
实施例2～67与对比例5的对比结果表明，第二阶段的高温加热和保温对初始样品的电化学性能影响极大。原因在于第二阶段是生成硫酸铁钠样品的阶段，对比例5使用的正极材料没有经过高温加热和保温，因此未能形成硫酸铁钠正极，测试所得的比容量大部分来自于物理吸附。
实施例2～67与对比例6,7的对比结果表明，当采用的两亲分子的HLB值在10～16以外时，初始样品的电化学性能相当，但搁置12个月后的样品电化学性能显著衰退，说明两亲分子的HLB值对保护效果具有一定影响；推测可能原因是HLB值太高或太低的两亲分子，难以在硫酸铁钠正极形成有效的保护层。
上面结合附图对本发明实施例作了详细说明，但本发明不限于上述实施例，在所属技术领域普通技术人员所具备的知识范围内，还可以在不脱离本发明宗旨的前提下作出各种变化。

Claims (10)

  1. 一种硫酸铁钠正极材料，其特征在于，所述正极材料包括硫酸铁钠和修饰所述硫酸铁钠的两亲分子，所述两亲分子的亲水端朝向所述硫酸铁钠，所述两亲分子的疏水端背向所述硫酸铁钠；所述两亲分子的HLB为10～16。
  2. 根据权利要求1所述的硫酸铁钠正极材料，其特征在于，所述两亲分子包括聚氧丙烯羊毛醇醚、聚氧乙烯水山梨醇单油酸酯、聚氧乙烯十六烷基醚、聚氧乙烯失水山梨醇三硬脂酸酯、聚氧乙烯月桂醚、聚氧乙烯失水山梨醇三油酸酯、聚氧乙烯氧丙烯油酸酯、聚氧乙烯羊毛脂衍生物、聚氧乙烯单油酸酯、聚氧乙烯单油酸酯、聚氧乙烯单棕榈酸酯、聚氧乙烯单硬脂酸酯、聚氧乙烯油醇醚、聚氧乙烯单月桂酸酯、聚氧乙烯烷基酚、聚氧乙烯乙酰化羊毛脂衍生物、聚氧乙烯山梨醇羊毛脂衍生物、聚氧乙烯烷基芳基醚、聚氧乙烯单月桂酸酯、聚氧乙烯月桂醚、聚氧乙烯蓖麻油、聚氧乙烯植物油、胆固醇醚、羊毛醇醚、聚氧乙烯失水山梨醇单月桂酸酯、聚氧乙烯失水山梨醇单硬脂酸酯、聚氧乙烯油醇醚、聚氧乙烯甲基葡萄糖苷倍半油酸酯、聚氧乙烯羊毛醇醚、聚氧乙烯失水山梨醇单油酸酯、聚氧乙烯单硬脂酸酯、聚氧乙烯单油酸酯、聚氧乙烯油基醚、聚氧乙烯十八醇、聚氧乙烯油醇、聚氧乙烯脂肪醇、聚乙二醇单棕榈酸酯、聚氧乙烯失水山梨醇单棕榈酸酯、聚氧乙烯十六烷基醇、聚氧乙烯氧丙烯硬脂酸酯和聚氧乙烯单硬脂酸酯中的至少一种。
  3. 一种如权利要求1或2所述的硫酸铁钠正极材料的制备方法，其特征在于，包括：
    将所述硫酸铁钠的制备原料、所述两亲分子、非极性溶剂和极性溶剂混合加热后除杂；
    所述混合加热包括依次进行的第一次加热和第二次加热；
    所述第一次加热的温度为50～100℃；所述第一次加热的时间为1～12h；
    所述第二次加热的温度为120～250℃；所述第二次加热的时间为1～12h。
  4. 根据权利要求3所述的制备方法，其特征在于，所述第一次加热的温度为70～90℃；所述第一次加热的时间为1～3h；优选地，所述第二次加热的温度为170～190℃；所述第二次加热的时间为3～5h。
  5. 根据权利要求3所述的制备方法，其特征在于，所述非极性溶剂包括苯、四氯化碳、己烷、异辛烷、二氯甲烷、环己烷、石油醚和戊烷中的至少一种。
  6. 根据权利要求3所述的制备方法，其特征在于，所述极性溶剂包括水、甲酰胺、丙酮、三氟乙酸、乙醇、氯仿、乙醚、乙酸、乙腈、异丙醇、甲醇、二甲基亚砜、乙腈、N,N-二甲基甲酰胺、六甲基磷酰胺、吡啶、四甲基乙二胺、三乙胺、正丁醇、二氧六环、四氢呋喃和甲酸甲酯 中的至少一种。
  7. 根据权利要求3所述的制备方法，其特征在于，所述硫酸铁钠的制备原料包括硫酸钠和硫酸亚铁水合物。
  8. 根据权利要求7所述的制备方法，其特征在于，所述极性溶剂、所述非极性溶剂、所述两亲分子、所述硫酸钠和所述硫酸亚铁水合物的比为1～20：1～20：10～500：5～6.75：10～13.5，其中，极性溶剂和非极性溶剂以体积升计算，两亲分子以质量克计算，硫酸钠和硫酸亚铁水合物以物质的量摩尔计算。
  9. 一种如权利要求1或2述的正极材料在钠离子电池制备中的应用。
  10. 一种如权利要求9所述的钠离子电池在二次电池领域的应用。
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CN119503889A (zh) * 2024-11-22 2025-02-25 湖南师范大学 一种混合醇析法制备多元素均匀掺杂型硫酸铁钠多孔钠电正极材料的方法
CN119864415A (zh) * 2025-03-19 2025-04-22 天目湖先进储能技术研究院有限公司 一种高性能硫酸铁钠聚阴离子正极材料及其制备方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116344824B (zh) * 2023-04-28 2024-02-02 中国科学院深圳先进技术研究院 一种硫酸铁钠正极材料及其制备方法和应用

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3624459A (en) * 1969-12-03 1971-11-30 Gen Electric Electrolyte composition for wet electrolytic capacitors
US20150340696A1 (en) * 2013-01-08 2015-11-26 Lg Chem, Ltd. Cathode active material for lithium-sulfur battery and manufacturing method therefor
WO2019051662A1 (zh) * 2017-09-13 2019-03-21 辽宁宏成供电有限公司 一种新型高电位多层碳包覆聚阴离子型钠离子电池正极材料及其制备方法
CN110224136A (zh) * 2019-07-26 2019-09-10 广东工业大学 一种高密度钠离子电池正极材料及其制备方法
US20210202946A1 (en) * 2019-12-09 2021-07-01 Soochow University Iron-based cathode material for sodium-ion battery, preparation method thereof, and corresponding sodium-ion full battery
CN115050934A (zh) * 2022-05-31 2022-09-13 四川大学 疏水亲油的Na2Fe2（SO4）3/C正极材料及其制备方法
US20220393157A1 (en) * 2020-08-11 2022-12-08 Lg Energy Solution, Ltd. Positive electrode active material for lithium-sulfur battery, preparation method thereof and lithium-sulfur battery comprising same
JP2023021654A (ja) * 2021-08-02 2023-02-14 株式会社東芝 正極、二次電池、電池パック及び車両
CN115832304A (zh) * 2022-12-06 2023-03-21 电子科技大学长三角研究院(湖州) 一种脂肪酸改性钠电正极材料的方法、制备方法及应用
CN115954447A (zh) * 2022-12-06 2023-04-11 电子科技大学长三角研究院(湖州) 一种疏水型聚合物包覆改性钠电正极材料、制备方法及电池
CN116344824A (zh) * 2023-04-28 2023-06-27 中国科学院深圳先进技术研究院 一种硫酸铁钠正极材料及其制备方法和应用

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110521036A (zh) * 2017-06-27 2019-11-29 日本电气硝子株式会社 钠离子二次电池用正极活性物质
CN114050246B (zh) * 2021-11-16 2023-02-07 郑州大学 微米级多孔硫酸亚铁钠/碳复合正极材料及其制备的钠离子电池或钠电池
CN114792798B (zh) * 2022-04-25 2023-05-05 湖北万润新能源科技股份有限公司 一种硅酸锰钠正极材料及其制备方法、其正极和电池

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3624459A (en) * 1969-12-03 1971-11-30 Gen Electric Electrolyte composition for wet electrolytic capacitors
US20150340696A1 (en) * 2013-01-08 2015-11-26 Lg Chem, Ltd. Cathode active material for lithium-sulfur battery and manufacturing method therefor
WO2019051662A1 (zh) * 2017-09-13 2019-03-21 辽宁宏成供电有限公司 一种新型高电位多层碳包覆聚阴离子型钠离子电池正极材料及其制备方法
CN110224136A (zh) * 2019-07-26 2019-09-10 广东工业大学 一种高密度钠离子电池正极材料及其制备方法
US20210202946A1 (en) * 2019-12-09 2021-07-01 Soochow University Iron-based cathode material for sodium-ion battery, preparation method thereof, and corresponding sodium-ion full battery
US20220393157A1 (en) * 2020-08-11 2022-12-08 Lg Energy Solution, Ltd. Positive electrode active material for lithium-sulfur battery, preparation method thereof and lithium-sulfur battery comprising same
JP2023021654A (ja) * 2021-08-02 2023-02-14 株式会社東芝 正極、二次電池、電池パック及び車両
CN115050934A (zh) * 2022-05-31 2022-09-13 四川大学 疏水亲油的Na2Fe2（SO4）3/C正极材料及其制备方法
CN115832304A (zh) * 2022-12-06 2023-03-21 电子科技大学长三角研究院(湖州) 一种脂肪酸改性钠电正极材料的方法、制备方法及应用
CN115954447A (zh) * 2022-12-06 2023-04-11 电子科技大学长三角研究院(湖州) 一种疏水型聚合物包覆改性钠电正极材料、制备方法及电池
CN116344824A (zh) * 2023-04-28 2023-06-27 中国科学院深圳先进技术研究院 一种硫酸铁钠正极材料及其制备方法和应用

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
TIANYI SONG; WENJIAO YAO; PINIT KIADKHUNTHOD; YONGPING ZHENG; NANZHONG WU; XIAOLONG ZHOU; SARAYUT TUNMEE; SUCHINDA SATTAYAPORN; YO: "A Low‐Cost and Environmentally Friendly Mixed Polyanionic Cathode for Sodium‐Ion Storage", ANGEWANDTE CHEMIE INTERNATIONAL EDITION, VERLAG CHEMIE, HOBOKEN, USA, vol. 59, no. 2, 14 November 2019 (2019-11-14), Hoboken, USA, pages 740 - 745, XP072098208, ISSN: 1433-7851, DOI: 10.1002/anie.201912272 *
YAN, QI : "Recent Development of Polyanionic Cathodes for Second Ion Batteries", ENERGY STORAGE SCIENCE AND TECHNOLOGY, CN, vol. 10, no. 3, 1 January 2021 (2021-01-01), CN , pages 872 - 886, XP093227817, ISSN: 2095-4239, DOI: 10.19799/j.cnki.2095-4239.2021.0133 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN119503889A (zh) * 2024-11-22 2025-02-25 湖南师范大学 一种混合醇析法制备多元素均匀掺杂型硫酸铁钠多孔钠电正极材料的方法
CN119864415A (zh) * 2025-03-19 2025-04-22 天目湖先进储能技术研究院有限公司 一种高性能硫酸铁钠聚阴离子正极材料及其制备方法

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