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CN-121990549-A - High-capacity sodium ion battery carbon negative electrode material and preparation method and application thereof

CN121990549ACN 121990549 ACN121990549 ACN 121990549ACN-121990549-A

Abstract

The invention relates to a high-capacity sodium ion battery carbon negative electrode material and a preparation method and application thereof, wherein the high-capacity sodium ion battery carbon negative electrode material is prepared by the following steps of S1, crushing petroleum coke to a target particle size, mixing hydrochloric acid, stirring at constant temperature t1, adding a sodium tripolyphosphate aqueous solution x with a certain mass, continuously stirring at constant temperature t2, filtering and washing to obtain precursor powder, mixing the precursor powder with a sodium tripolyphosphate aqueous solution y containing glucose, spray-drying, mixing with high-softening-point asphalt, fusing and granulating, and finally carrying out gradient heating treatment under an inert atmosphere, and depolymerizing and demagnetizing the obtained material to obtain the carbon negative electrode material. Compared with the prior art, the sodium ion battery carbon negative electrode material with high capacity and long cycle life is obtained.

Inventors

  • LI BING
  • HUANG HONGLIANG
  • LU QI
  • XIE TINGTING
  • DUAN YU
  • DONG YUJIA
  • WANG ZHICHENG

Assignees

  • 中石油(上海)新材料研究院有限公司
  • 中国石油天然气股份有限公司

Dates

Publication Date
20260508
Application Date
20241107

Claims (10)

  1. 1. The preparation method of the high-capacity sodium ion battery carbon negative electrode material is characterized by comprising the following steps of: s1, crushing petroleum coke to a target particle size, mixing hydrochloric acid, stirring at a constant temperature for t1, adding a sodium tripolyphosphate aqueous solution x with a certain mass, continuously stirring at a constant temperature for t2, and filtering and washing to obtain precursor powder; S2, mixing the precursor powder with a sodium tripolyphosphate aqueous solution y containing glucose, spray-drying, mixing with high-softening-point asphalt, performing fusion granulation, and performing gradient heating treatment under an inert atmosphere to obtain a material, and depolymerizing and demagnetizing the material to obtain the carbon negative electrode material.
  2. 2. The method for preparing the carbon cathode material of the high-capacity sodium ion battery according to claim 1, wherein the petroleum coke in the step S1 is vacuum residue of petroleum, black solid coke is generated by a coking device, and the target particle size D50=2-5 μm of the petroleum coke.
  3. 3. The method for preparing the carbon cathode material of the high-capacity sodium ion battery according to claim 1, wherein the dosage ratio of petroleum coke to hydrochloric acid in the step S1 is (400-600) g (0.5-2) L; the pH=1 of the hydrochloric acid, and the concentration is 0.05-0.15 mol/L; the sodium tripolyphosphate aqueous solution x is formed by mixing alpha sodium tripolyphosphate and water according to the mass ratio of 6-13:100, and the mass ratio of the alpha sodium tripolyphosphate to petroleum coke is 5-10:100.
  4. 4. The preparation method of the high-capacity sodium ion battery carbon cathode material according to claim 1 is characterized in that the constant-temperature stirring t1 in the step S1 is carried out under the conditions that an airtight reaction kettle is filled with oxygen at the temperature of 20-40 ℃ and the stirring speed of 50-200 r/min for 1-3 hours; The constant temperature stirring t2 is carried out under the conditions that the reaction kettle is closed, the oxygen atmosphere is adopted, the stirring speed is 50-200 r/min at 40-100 ℃, and the stirring time is 1-4 h.
  5. 5. The method for preparing the carbon cathode material of the high-capacity sodium ion battery according to claim 1, wherein the step S1 is filtering and washing, namely washing and filtering with deionized water for a plurality of times until the pH value of the filtrate is less than or equal to 10.
  6. 6. The preparation method of the high-capacity sodium ion battery carbon negative electrode material according to claim 1 is characterized in that in the step S2, glucose-containing sodium tripolyphosphate aqueous solution y is prepared by mixing glucose, beta-sodium tripolyphosphate and deionized water according to a mass ratio of 1-5:3-13:100.
  7. 7. The preparation method of the high-capacity sodium ion battery carbon anode material according to claim 1, wherein in the step S2, precursor powder and sodium tripolyphosphate aqueous solution y containing glucose are uniformly mixed according to a mass ratio of 100:150-250 to form a mixture A.
  8. 8. The preparation method of the high-capacity sodium ion battery carbon cathode material according to claim 1 is characterized in that in the step S2, spray drying is carried out to obtain a mixture A, powder particles are obtained through spray drying under the conditions that the inlet temperature is 200-250 ℃ and the outlet temperature is less than 105 ℃, the particles and high-softening-point asphalt are uniformly mixed according to the mass ratio of 100:10-20 to obtain a mixture B, the mixture B is loaded into a graphite sagger, gradient heating treatment is carried out, the heating rate is 2-10 ℃ and the temperature is raised to 650 ℃ (T1), the temperature is kept for 2-6h, then the temperature is raised to 900-1200 ℃ (T2) through 2-5 ℃ and the temperature is kept for 4-12h.
  9. 9. A high capacity sodium ion battery carbon negative electrode material made by the method of any one of claims 1-8.
  10. 10. Use of the high capacity sodium ion battery carbon negative electrode material according to claim 9, wherein the carbon negative electrode material is used as a negative electrode material of a sodium ion secondary battery.

Description

High-capacity sodium ion battery carbon negative electrode material and preparation method and application thereof Technical Field The invention relates to the technical field of sodium ion batteries, in particular to a high-capacity sodium ion battery carbon negative electrode material, a preparation method and application thereof. Background The commercial scale application of sodium ion batteries is limited by the lack of low cost, high performance carbon negative electrode materials. Petroleum coke is an excellent raw material for preparing carbon materials, has the advantages of low cost, simple carbonization process and the like, and can greatly exert the advantage of low cost of sodium ion batteries when being applied to negative electrode materials of sodium ion batteries. However, the problems of poor cycle life, low cell energy density and the like of sodium ion batteries are caused by higher iron, nickel, vanadium and other metal impurities. The existing technical schemes for removing metal impurities comprise an acid treatment process and an alkali treatment process, and the acid treatment process and the alkali treatment process can have the effect of removing metal impurities, but all cause severe change of the structure of petroleum coke materials, so that the obtained carbon materials have extremely large specific surface area, and the results of extremely low first-week coulomb efficiency, poor cycle performance, low energy density and the like of the sodium ion battery are caused. In addition, the poor wettability between petroleum coke and water also results in the need to consume large amounts of water in the acid or base treatment process, which causes wastewater treatment problems. Chinese patent CN117923459A adopts hydrochloric acid and the like to treat petroleum coke, and then obtains the porous carbon anode material with larger specific surface area after high-temperature treatment. The specific surface area of the finally obtained carbon material is overlarge, and the 002 diffraction peak layer spacing is smaller than 0.36nm, so that the carbon material shows extremely low initial cycle coulombic efficiency and poor cycle performance after being used as a negative electrode material of a sodium ion battery, and the specific capacity is lower than 280mAh/g, so that the commercialization requirement is not met. The Chinese patent CN 114956037 uses potassium hydroxide and borax to treat petroleum coke, and then uses high-temperature treatment to obtain the carbon material, its 002 diffraction peak layer spacing is only 0.35nm, and its specific capacity is less than 280mAh/g. Chinese patent CN 117776147 is used for solving the problem of overlarge specific surface area of petroleum coke after alkali treatment, and filling operation is carried out by utilizing asphalt to obtain the carbon material with 002 diffraction peak layer spacing exceeding 0.38nm, but the specific capacity is lower than 250mAh/g. Chinese patent CN116119643B discloses a preparation method of a high-rate long-cycle pyrolytic carbon negative electrode material for sodium storage, 1) crushing carbon-based precursor materials such as coke and coking to reach a specified particle size to obtain a carbon-based primary precursor, 2) performing pretreatment such as acid-alkali washing impurity removal or alkali activation on the primary precursor to obtain a pretreated secondary precursor, 3) granulating/pyrolysis the primary precursor to obtain a finished product of the carbon-based negative electrode material, and 4) further performing surface modification on the carbon-based negative electrode material to obtain the optimized pyrolytic carbon negative electrode material. The prepared carbon-based negative electrode material has the advantages of large reversible capacity, high initial charge and discharge coulomb efficiency, good cycle performance and the like when being used in sodium ion batteries. However, the maximum value of the reversible specific capacity of the carbon material prepared by the technical scheme is only 255mAh/g, the requirement of a commercial sodium ion battery on the anode material cannot be met, the tap density of the carbon material is reduced by the alkali activation pore-forming operation, and the energy density of the sodium ion battery is further influenced. Therefore, the technical scheme still needs to be improved. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide a high-capacity sodium ion battery carbon negative electrode material with high thermal stability, a preparation method and application thereof, wherein the carbon skeleton structure of petroleum coke is kept stable while metal impurities in the petroleum coke are solved, and the sodium ion battery carbon negative electrode material with high capacity and long cycle life is prepared. The invention aims at realizing the following technical scheme that the preparation method of the