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CN-121237851-B - Biomass composite material for negative electrode of sodium ion battery and preparation method

CN121237851BCN 121237851 BCN121237851 BCN 121237851BCN-121237851-B

Abstract

The invention discloses a biomass composite material for a sodium ion battery cathode and a preparation method thereof, belonging to the technical field of sodium ion batteries, wherein the composite material comprises 90-98 parts of biomass-based hard carbon, 2-10 parts of bismuth/antimony salt solution or bismuth/antimony oxide, and the preparation method thereof. The method takes low-cost natural agricultural/industrial waste as a carbon source, takes bismuth/antimony or a compound as an important active substance, forms a porous carbon structure through pre-carbonization, mixes the bismuth/antimony or the compound with carbide, tightly wraps the bismuth/antimony and carbon through medium-temperature asphalt, activated gas and the like to form the composite material of the bismuth/antimony core-shell structure, introduces the bismuth/antimony at low cost, improves the electrochemical activity of a hard carbon material, simultaneously utilizes the effect of carbon wrapping, inhibits the system expansion in the bismuth/antimony sodium storage process, improves the stability of the material, and has the advantages of simple process, easily-adjustable composition, higher performance, wide application range and good application prospect.

Inventors

  • WENG BAICHENG
  • XU FENGHUA

Assignees

  • 惠州市鸣凤新材料科技有限公司

Dates

Publication Date
20260505
Application Date
20250923

Claims (6)

  1. 1. A preparation method of a biomass composite material for a sodium ion battery cathode is characterized by comprising the following steps: The biomass composite material for the sodium ion battery cathode comprises 90-98 parts of biomass-based hard carbon and 2-10 parts of bismuth/antimony salt solution or bismuth/antimony oxide, wherein the biomass-based hard carbon is one or more of phyllostachys pubescens, waste bamboo powder thereof, bamboo craft tailings, packaging paper/box, camellia oleifera shells and almond shells, and the bismuth/antimony salt solution is nitrate solution of bismuth/antimony or acetate solution of bismuth/antimony; The preparation method of the biomass composite material for the sodium ion battery cathode comprises the following steps: S1, pretreating a biomass raw material, sequentially stirring and soaking in an organic solvent, acid or an oxidant, and washing to obtain a precursor; S2, carbonizing the precursor under the protection of inert gas to obtain carbonized material; S3, mixing the carbonized material with bismuth/antimony salt solution or bismuth/antimony oxide according to a proportion, adding a closed-pore reagent, and then introducing inert gas to carry out carbonization treatment or directly carrying out carbonization treatment in an activated gas to obtain the bismuth/antimony carbide composite material, wherein the closed-pore reagent is medium-temperature asphalt or sugar substances, the proportion is 1-10 wt%, the activated gas is one of acetylene, propyne, a mixed gas of methane and nitrogen and a mixed gas of methane and argon, the proportion of the activated gas is 5-15%, the carbonization treatment temperature is 600-950 ℃, and the carbonization time is 2-6 h.
  2. 2. The method for preparing the biomass composite material for the negative electrode of the sodium ion battery according to claim 1, wherein in the step S1, the biomass raw material is one of phyllostachys pubescens, phyllostachys pubescens and waste bamboo powder thereof, bamboo craft tailings, packaging paper/box, camellia oleifera shell and almond shell.
  3. 3. The method for preparing the biomass composite material for the negative electrode of the sodium ion battery according to claim 1, wherein in the step S1, the organic solvent is one or more of petroleum ether, acetone, ethanol, methanol and isopropanol, the acid is one of hydrofluoric acid, hydrochloric acid and sulfuric acid, and the oxidant is one of sodium hypochlorite and sodium chlorite; the organic solvent is used for soaking for 6-12 hours at 20-60 ℃, and the acid or oxidant is used for soaking for 6-12 hours at 20-80 ℃.
  4. 4. The preparation method of the biomass composite material for the negative electrode of the sodium ion battery, which is disclosed in claim 1, is characterized in that in the step S2, the carbonization treatment temperature is 350-800 ℃, the heating rate is 5-10 ℃ per minute, and the treatment time is 1-4 hours.
  5. 5. The preparation method of the biomass composite material for the negative electrode of the sodium ion battery, which is disclosed in claim 1, is characterized in that in the S3, the mass ratio of bismuth/antimony salt solution to carbonized material is 1:10-2:98, and the carbonized material and the bismuth/antimony salt solution are dried under the condition of 80 ℃ after being mixed; The mixing mode of bismuth/antimony oxide and carbonized material is ball milling mixing, and the ball milling time is 6-48 h.
  6. 6. The method for preparing the biomass composite material for the negative electrode of the sodium ion battery according to claim 1, wherein in the carbonization treatment process of introducing inert gas after adding a closed-pore reagent into the S3, the inert gas is argon or nitrogen, the flow is 30-150 sccm, the carbonization temperature is 600-950 ℃, and the time is 0.5-6 hours.

Description

Biomass composite material for negative electrode of sodium ion battery and preparation method Technical Field The invention relates to the technical field of sodium ion batteries, in particular to a biomass composite material for a negative electrode of a sodium ion battery and a preparation method thereof. Background Compared with the lithium ion battery, the lithium ion battery has wide sources of raw materials, low economic cost, good safety and excellent low-temperature performance, so that the lithium ion battery has a good research prospect, but the reversible charge-discharge capacity and the initial efficiency of the sodium ion battery in the prior art are generally low, and the development of the sodium ion battery is severely restricted. The negative electrode material is a carrier of ions and electrons in the charge and discharge process of the sodium ion battery, and determines energy storage and release. The negative electrode materials currently applicable to sodium ion batteries include amorphous carbon, metal compounds, alloy materials and the like. Bismuth, antimony and oxides thereof in the alloy compound have a theoretical capacity of 660-1300 mAh/g, and are considered to be potential negative electrode materials of sodium ion batteries. However, the volume change value of the alloy compound in the charge and discharge process is more than 150%, the pulverization is serious, and the cycling stability of the negative electrode of the sodium ion battery is seriously affected. In order to improve the cycling stability of such electrode materials, a great deal of research has been focused on the preparation of ultrafine nanoparticles and the compounding of these materials with carbon-based materials. If antimony is mixed with multi-wall carbon nano tube/graphene and the like, synthesizing the nano composite fiber of antimony and carbon by using an electrostatic spinning method. The existing synthesis method comprises a mass separation soft landing method, a coprecipitation method, an atomic layer deposition method, a hydrothermal synthesis method and an electrostatic adsorption method, wherein the mass separation soft landing technology needs ultrahigh vacuum preparation conditions, large-scale production is difficult to achieve, the coprecipitation method is commonly used for preparing high-content multi-component composite materials, the atomic layer deposition method needs specific equipment to prepare nano particles, development of the method is limited, the hydrothermal synthesis method has a certain potential safety hazard due to hydrothermal reaction, the industrial production process is not facilitated, the spatial distribution of functional groups on a carrier in the electrostatic adsorption method is generally uneven, various types of surface defects can have non-negligible influence on the adsorption behavior of metal complexes, and the traditional preparation methods are complex in process, high in cost and cannot be applied on a large scale. Based on the problems, a biomass composite material for a sodium ion battery cathode and a preparation method thereof are provided. Disclosure of Invention The invention aims to provide a biomass composite material for a sodium ion battery cathode and a preparation method thereof, which are used for solving the problems in the background technology. The biomass composite material for the negative electrode of the sodium ion battery comprises 90-98 parts of biomass-based hard carbon, and 2-10 parts of bismuth/antimony salt solution or bismuth/antimony oxide. Preferably, the biomass-based hard carbon is one or more of phyllostachys pubescens, phyllostachys pubescens and waste bamboo powder thereof, bamboo craft tailings, packaging paper/box, oil tea shell, almond shell and the like. Preferably, the bismuth/antimony salt solution is a nitrate solution of bismuth/antimony or an acetate solution of bismuth/antimony. The invention also provides a preparation method of the biomass composite material for the sodium ion battery cathode, which comprises the following steps: S1, pretreating a biomass raw material, sequentially stirring and soaking in an organic solvent, acid or an oxidant, and washing to obtain a precursor; S2, carbonizing the precursor under the protection of inert gas to obtain carbonized material; s3, mixing the carbonized material with bismuth/antimony salt solution or bismuth/antimony oxide in proportion, adding a closed pore reagent, and then introducing inert gas for carbonization treatment or directly carbonizing treatment in activated gas to obtain the bismuth/antimony carbide composite material. Preferably, in the step S1, the biomass raw material is one of phyllostachys pubescens, waste bamboo powder, bamboo craft tailing, packaging paper/box, camellia oleifera shell and almond shell; the pretreatment of the raw materials comprises the steps of crushing, wherein the median particle size of the crushed materials obtained afte