CN115050925A - Electrode material, preparation method, electrode plate and battery - Google Patents

Electrode material, preparation method, electrode plate and battery Download PDF

Info

Publication number
CN115050925A
CN115050925A CN202210774823.4A CN202210774823A CN115050925A CN 115050925 A CN115050925 A CN 115050925A CN 202210774823 A CN202210774823 A CN 202210774823A CN 115050925 A CN115050925 A CN 115050925A
Authority
CN
China
Prior art keywords
electrode material
carbon
ions
carbon paper
porous sic
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202210774823.4A
Other languages
Chinese (zh)
Other versions
CN115050925B (en
Inventor
宋佃凤
方帅男
吴立群
徐汝义
王燕
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shandong Renfeng Speical Materials Co ltd
Original Assignee
Shandong Renfeng Speical Materials Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shandong Renfeng Speical Materials Co ltd filed Critical Shandong Renfeng Speical Materials Co ltd
Priority to CN202210774823.4A priority Critical patent/CN115050925B/en
Publication of CN115050925A publication Critical patent/CN115050925A/en
Application granted granted Critical
Publication of CN115050925B publication Critical patent/CN115050925B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/133—Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • 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
    • 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/134—Electrodes based on metals, Si or alloys
    • 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1393—Processes of manufacture of electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1395—Processes of manufacture of electrodes based on metals, Si or alloys
    • 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
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/386—Silicon or alloys based on silicon
    • 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
    • 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
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
    • 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
    • H01M4/64—Carriers or collectors
    • H01M4/66—Selection of materials
    • H01M4/663—Selection of materials containing carbon or carbonaceous materials as conductive part, e.g. graphite, carbon fibres
    • 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
    • H01M2004/021—Physical characteristics, e.g. porosity, surface area
    • 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
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • 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

Abstract

The invention discloses an electrode material, a preparation method, an electrode plate and a battery, relates to the technical field of batteries and aims to solve the problems of low specific capacity and poor cycle stability of the conventional electrode material. The electrode material comprises a carbon paper-based framework and a composite layer formed on the surface of the carbon paper-based framework, wherein the composite layer contains porous SiC and metal ions which are crosslinked together, and a silicon simple substance contained in the porous SiC is dispersed in a carbon simple substance contained in the porous SiC. The preparation method is used for preparing the electrode material, the electrode plate uses the electrode material, and the battery uses the electrode material. The electrode material, the preparation method, the electrode plate and the battery provided by the invention are used for improving the specific capacity and the cycling stability of the battery.

Description

Electrode material, preparation method, electrode plate and battery
Technical Field
The invention relates to the technical field of batteries, in particular to an electrode material, a preparation method, an electrode plate and a battery.
Background
In recent years, with the development of technology, secondary batteries have been widely used in various fields. The research on the key materials of the secondary battery tends to be athermalized, wherein, the research on the cathode material of the ion battery is very concerned, and the silicon-based material and the metal oxide composite material belong to the research hot spot of the cathode material of the ion battery. However, since the cost of the silicon-based material and the metal oxide composite material is high, the charge-discharge platform is unstable, and the capacity of the negative electrode is obviously attenuated after multi-cycle cycling, so that the application of the composite material in practice is limited.
Therefore, the carbon-based material is utilized as the anode material of the ion battery to enter the human visual field. The carbon-based material is non-toxic and is relatively stable in air in a discharge state. However, when the carbon-based material is used as the negative electrode material of the ion battery, the distance between graphite layers is too small, so that the sodium ions with larger radius are embedded between the graphite layers, larger energy is required, reversible deintercalation cannot be performed in an effective potential window, and energy attenuation is fast, so that the cycle stability of the ion battery is poor. Therefore, it is necessary to develop a carbon-based negative electrode material having a high specific capacity and good cycle stability.
Disclosure of Invention
The invention aims to provide an electrode material, a preparation method, an electrode plate and a battery, which improve the specific capacity and the cycling stability of the electrode material of an ion battery, thereby improving the safety of the battery.
In a first aspect, the present invention provides an anode material comprising: the composite layer contains porous SiC and metal ions which are crosslinked together, and a silicon simple substance contained in the porous SiC is dispersed in a carbon simple substance contained in the porous SiC.
Compared with the prior art, the electrode material provided by the invention has the following advantages:
in the electrode material provided by the invention, the composite layer is formed on the surface of the carbon paper-based framework, and the composite layer contains porous SiC and metal ions which are crosslinked together, so that the porous SiC and the metal ions can form an alloy with a three-dimensional network structure, and the specific capacity of the electrode material can be improved. Moreover, the three-dimensional network structure has small pores and low porosity, so that the moving channels of metal ions are reduced, on one hand, the electrolyte is not easy to be in direct contact with the metal ions, and on the other hand, if free metal ions exist, the electrolyte is not easy to enter the electrolyte through the moving channels. Therefore, in the electrode material provided by the invention, metal ions are difficult to react with the electrolyte, so that the decomposition of the metal ions on the electrolyte and the precipitation of metal are reduced, the gas expansion of the electrolyte is avoided, and the cycle stability and the safety of the battery are improved. Meanwhile, according to the electrode material provided by the embodiment of the application, when the silicon simple substance contained in the porous SiC is dispersed in the carbon simple substance contained in the porous SiC, the volume change is small in the charging and discharging process of the simple substance carbon, so that the volume expansion of the silicon in the discharging process can be buffered by using the carbon simple substance, the silicon-based electrode material is prevented from generating cracks until being powdered, the contact between the electrode material and a current collector is enhanced, the energy attenuation of a metal electrode plate is slowed down, and the battery capacity is improved. The extrusion of the electrode plate caused by the internal stress of the battery due to volume expansion can be avoided, and the risk of electrode plate fracture is reduced. In addition, the simple substance carbon provided by the embodiment of the application has better conductivity, and can improve the electronic conductivity of the electrode material, so that the cycle stability of the battery is improved.
Therefore, the electrode material provided by the invention can form a composite layer on the surface of the carbon paper-based framework, and the specific capacity and the cycling stability of the negative electrode material of the ion battery are improved, so that the safety of the battery is improved.
In a second aspect, the present invention also provides a method for preparing an electrode material, comprising:
mixing the porous SiC nano material with metal ions by using an initiator to obtain a composite material;
preparing a carbon paper-based framework by using short carbon fibers;
and forming the composite material on the surface of the carbon paper-based framework to form a composite layer on the surface of the carbon paper-based framework, so as to obtain the electrode material.
Compared with the prior art, the beneficial effects of the preparation method of the electrode material provided by the invention are the same as those of the electrode material provided by the first aspect, and the details are not repeated here.
In a third aspect, the invention further provides an electrode sheet, which comprises the electrode material provided by the first aspect.
Compared with the prior art, the electrode plate provided by the invention has the same beneficial effects as the electrode material of the first aspect, and the details are not repeated here.
In a fourth aspect, the invention also provides a battery comprising the electrode material provided in the first aspect.
Compared with the prior art, the beneficial effects of the battery provided by the invention are the same as those of the electrode material in the first aspect, and the details are not repeated here.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:
fig. 1 is a schematic structural view of a battery according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of an electrode material according to an embodiment of the present invention;
FIG. 3 is a flow chart illustrating the preparation of an electrode material according to an embodiment of the present invention;
FIG. 4 is a flow chart of the preparation of porous SiC nanomaterial according to an embodiment of the present invention;
fig. 5 is a flow chart of the preparation of the carbon paper-based skeleton according to the embodiment of the present invention.
Reference numerals:
100-battery, 101-diaphragm, 102 a-first current collector, 102 b-second current collector, 103-anode material, 104-cathode material, 200-electrode material, 201-carbon paper-based framework, and 202-composite layer.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more apparent, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. The meaning of "a number" is one or more unless specifically limited otherwise.
With the rapid growth of new energy automobiles in the market, related fields such as upstream materials and the like are rapidly developed. The requirement of people on the endurance of new energy automobiles is higher and higher, and the requirement of consumers on the endurance mileage of the automobiles is continuously improved depending on the energy density of batteries, so that the high energy density becomes the future development direction of power batteries.
Silicon-based materials have high theoretical lithium storage capacity (4200mAh/g), and are considered to be the most promising next-generation anode materials for graphite replacement. However, during the charging and discharging processes of the sodium ion battery, the repeated desorption and intercalation of sodium ions can cause huge volume expansion of the silicon-based material, and the volume expansion rate is even up to 300%, so that the structure of the silicon-based material is easily damaged and mechanically pulverized, the electrode structure is collapsed, the electrode material is peeled off, and the cycle performance of the electrode material is seriously reduced. Meanwhile, when the silicon-based material is applied to a negative electrode, silicon is continuously exposed to an electrolyte due to the volume effect of the silicon-based material in the charging and discharging processes, so that a stable Solid Electrolyte Interface (SEI) film is difficult to form on the surface of the negative electrode, and sodium ions contained in the electrolyte are greatly consumed, so that the first charging and discharging efficiency of the silicon-based material is reduced and the capacity of the silicon-based material is rapidly attenuated. In addition, silicon is a semiconductor material and has low conductivity, and the silicon-based material serving as the negative electrode also reduces the transmission rate of sodium ions, so that the specific capacity of the battery is reduced.
In view of the above problems, embodiments of the present invention provide a battery, which may include an electrode material of an embodiment of the present invention, so as to improve the specific capacity, the cycling stability and the safety of an electrode material of an ion battery. It is to be understood that the electrode material may be defined as a negative electrode material, and the ion battery may further include a positive electrode material, a current collector, a separator, and an electrolyte. A separator may be defined having opposing first and second surfaces, a positive electrode material positioned between the first current collector and the first surface, and a negative electrode material positioned between the second current collector and the second surface. Fig. 1 shows a schematic structural diagram of a battery according to an embodiment of the present invention, and as shown in fig. 1, a battery 100 according to an embodiment of the present invention includes a separator 101, and a first current collector 102a, a positive electrode material 103, a negative electrode material 104, and a second current collector 102b disposed on both sides of the separator 101.
In practical applications, the battery according to the embodiment of the present invention may be a sodium ion battery, a lithium ion battery, an aluminum ion battery, or other ion batteries, which is not described in detail herein.
The electrode material provided by the embodiment of the invention can be applied to the battery. Fig. 2 shows a schematic structural diagram of an electrode material according to an embodiment of the present invention. As shown in fig. 2, an electrode material 200 according to an embodiment of the present invention includes a carbon paper-based skeleton 201 and a composite layer 202 formed on a surface of the carbon paper-based skeleton, the composite layer 202 includes porous SiC and metal ions cross-linked together, and a silicon simple substance included in the porous SiC is dispersed in a carbon simple substance included in the porous SiC.
In the electrode material provided by the invention, the composite layer is formed on the surface of the carbon paper-based framework, and the composite layer contains porous SiC and metal ions which are crosslinked together, so that the porous SiC and the metal ions can form an alloy with a three-dimensional network structure, and the specific capacity of the electrode material can be improved. Moreover, the three-dimensional network structure has small pores and low porosity, so that the moving channels of metal ions are reduced, on one hand, the electrolyte is not easy to be in direct contact with the metal ions, and on the other hand, if free metal ions exist, the electrolyte is not easy to enter the electrolyte through the moving channels. Therefore, in the electrode material provided by the invention, metal ions are difficult to react with the electrolyte, so that the decomposition of the metal ions on the electrolyte and the precipitation of metal are reduced, the gas expansion of the electrolyte is avoided, and the cycle stability and the safety of the battery are improved. Meanwhile, according to the electrode material provided by the embodiment of the application, when a silicon simple substance contained in porous SiC is dispersed in a carbon simple substance contained in the porous SiC, the volume change of the simple substance carbon in the charging and discharging processes is small, so that the volume expansion of silicon in the discharging process can be buffered by using the carbon simple substance, the silicon-based electrode material is prevented from generating cracks until being powdered, the contact between the electrode material and a current collector is enhanced, the energy attenuation of a metal electrode plate is slowed down, and the battery capacity is improved. The extrusion of the electrode plate caused by the internal stress of the battery due to volume expansion can be avoided, and the risk of electrode plate fracture is reduced. In addition, the simple substance carbon provided by the embodiment of the application has better conductivity, and can improve the electronic conductivity of the electrode material, so that the cycle stability of the battery is improved.
Therefore, the electrode material provided by the invention can form a composite layer on the surface of the carbon paper-based framework, and the specific capacity and the cycling stability of the negative electrode material of the ion battery are improved, so that the safety of the battery is improved.
In an achievable mode, the porous SiC of the embodiment of the invention has a nano porous network structure, and the mass ratio of the porous SiC to the metal ions is (20-50): (40-75). Therefore, the porous SiC has many pores and is in a nano level, so that the contact area between the metal ions and the surface of the porous SiC is increased, and under the condition of the mass ratio, the contact area between the metal ions and the porous SiC during the crosslinking reaction is promoted under the action of the initiator, so that the porous SiC and the metal ions are combined together more densely. Meanwhile, because the specific surface area of the porous SiC is large, a small amount of porous SiC can load a large amount of metal ions, so that the use amount of the metal ions can be reduced, and the production cost is saved.
In practical applications, the metal ions of the embodiments of the present invention may include at least one of P-region metal ions and transition metal ions. It is to be understood that the metal ion may be present as a metal salt, and the P block metal may include the metal elements of the P block elements including the group IVA and group VA elements of the periodic table. The group IVA elements are also called carbon group elements and comprise carbon C, silicon Si, germanium Ge, tin Sn, lead Pb and other elements; the VA group elements are also called nitrogen group elements and comprise nitrogen N, phosphorus P, arsenic As, antimony Sb, bismuth Bi and other elements.
Illustratively, the P-block metal ions include at least one of germanium ions, tin ions, lead ions, antimony ions, and bismuth ions or other P-block metal elements. The transition metal ions include at least one of chromium ions, manganese ions, iron ions, cobalt ions, nickel ions, copper ions, zinc ions, palladium ions, silver ions, platinum ions, gold ions, and mercury ions.
In an alternative mode, the carbon paper-based skeleton according to the embodiment of the present invention is a char formed of chopped carbon fibers including carbon fibers and water-soluble fibers, and the surface of the carbon paper-based skeleton is formed with a thermosetting phenol resin. The chopped carbon fibers comprise, by mass, 85-100 parts of carbon fibers and 0-15 parts of water-soluble carbon fibers. The diameter of the carbon fiber is 5um ~ 10um, the length of the carbon fiber is 5mm ~ 10mm, the diameter of the water-soluble fiber is 7um ~ 15um, the length of the water-soluble fiber is 5mm ~ 10 mm. The carbon paper-based framework of the embodiment of the invention is a carbide formed by chopped carbon fibers of carbon fibers and water-soluble fibers, and the carbon fibers and the water-soluble fibers have small diameters and short lengths, so that the carbon paper-based framework has high porosity and is more favorable for storing sodium ions. Meanwhile, a certain amount of water-soluble fiber is added into the carbon fiber so as to increase certain strength when the carbon paper is subjected to de-screening. Since the mechanical properties of a base paper for carbon paper made of a char formed of carbon fibers and chopped carbon fibers of water-soluble fibers are poor, the mechanical strength, heat resistance and electrical properties of the base paper for carbon paper are improved by impregnating the base paper for carbon paper with a thermosetting phenol resin.
Exemplarily, the charcoal paper-based skeleton further comprises polyethylene oxide and polyvinyl alcohol, and the mass ratio of the chopped carbon fibers to the polyethylene oxide to the polyvinyl alcohol is (1-2): (0.1 to 0.5) and (0.1 to 0.3). According to the embodiment of the invention, the polyethylene oxide and the polyvinyl alcohol are added into the water containing the chopped carbon fibers, so that the adhesion and the film forming property of the fibers can be improved. Meanwhile, the polyethylene oxide can be used as a dispersing agent in the slurry to uniformly disperse the carbon fibers and the water-soluble fibers, and the polyvinyl alcohol can also be used as a surface sizing agent, so that the wear resistance, folding resistance and tearing resistance of the carbon paper can be improved, and the glossiness, smoothness and printing adaptability of the carbon paper can also be improved. Therefore, the carbon paper with uniformly dispersed fibers and good glossiness can be prepared by adding the polyethylene oxide and the polyvinyl alcohol into the chopped carbon fibers in the embodiment of the invention.
The embodiment of the invention also provides a preparation method of the electrode material, which can be used for preparing the electrode material of the embodiment of the invention. Fig. 3 shows a schematic flow chart of a method for producing an electrode material according to an embodiment of the present invention. As shown in fig. 3, the method for preparing the electrode material according to the embodiment of the present invention includes:
step 301: and mixing the porous SiC nano material with metal ions by using an initiator to obtain the composite material.
For example, the porous SiC nanomaterial may be mixed with a metal salt solution and an initiator with stirring, and then the PH of the mixed solution may be adjusted to neutral by using an HCl solution or an NaOH solution. At this time, the porous SiC and the metal ions can be made to form an alloy of a three-dimensional network structure under the action of the initiator, so that the specific capacity of the electrode material can be improved. Moreover, the three-dimensional network structure has small pores and low porosity, so that the moving channels of metal ions are reduced, on one hand, the electrolyte is not easy to be in direct contact with the metal ions, and on the other hand, if free metal ions exist, the electrolyte is not easy to enter the electrolyte through the moving channels. Therefore, the decomposition of metal ions to the electrolyte and the precipitation of metal are reduced, the flatulence of the electrolyte is avoided, and the circulation stability and the safety of the battery are improved.
For example: the above metal salt solution may include at least one of a Ge salt, a Sn salt, a Pb salt, an Sb salt, a Bi salt, and a transition metal salt. The initiator may include at least one of ammonium dihydrogen phosphate, ammonium dihydrogen carbonate, ammonium carbonate, and ammonium hydrogen carbonate. The molar concentration of the metal salt solution is 10 mol/L-60 mol/L. The mass percentages of the porous SiC nanometer material, the metal salt solution and the initiator are respectively 20-50%, 40-75% and 20-50%.
Step 302: the carbon paper-based framework is prepared by utilizing the short carbon fibers.
The embodiment of the invention uses the chopped carbon fibers to prepare the carbon paper-based framework, and the chopped carbon fibers have small diameter and short length, so that the carbon paper-based framework has high porosity and is more favorable for storing sodium ions.
Step 303: and forming the composite material on the surface of the carbon paper-based framework to form a composite layer on the surface of the carbon paper-based framework, so as to obtain the electrode material.
Illustratively, the carbon paper-based framework is immersed in a dispersion liquid of the composite material, then hydrothermal reaction is carried out, so that the composite material is formed on the surface of the carbon paper-based framework, a composite layer is formed on the surface of the carbon paper-based framework, and then the carbon paper-based framework is taken out and dried to obtain the electrode material. Wherein the reaction time of the hydrothermal reaction can be 30 min-60 min, and the reaction temperature can be 180-400 ℃. According to the electrode material provided by the invention, the carbon paper-based framework is soaked in the dispersion liquid of the composite material, and then the hydrothermal reaction is carried out, so that the composite material can be uniformly and compactly formed on the surface of the carbon paper-based framework, and the specific capacity of the electrode material can be improved.
In an alternative manner, fig. 4 shows a flow chart of the preparation of the porous SiC nanomaterial in the embodiment of the present invention, and as shown in fig. 4, before the porous SiC nanomaterial is mixed with metal ions by using an initiator to obtain a composite material, the preparation method of the porous SiC nanomaterial in the embodiment of the present invention includes:
step 401: the silicon source and the carbon source are mixed and the resulting mixture is ground to a nanoscale powder.
The pulping and papermaking industry is one of the important industries of national economy in China, and the papermaking black liquor is used as a byproduct of the pulping and papermaking process and contains abundant lignin, cellulose, hemicellulose, trace metal elements, Si, S and other elements. The discharge of black liquor from paper making can cause serious environmental pollution problems.
Illustratively, the silicon source and the carbon source can be derived from papermaking black liquor, and the papermaking black liquor is evaporated and concentrated in an oven at 70-120 ℃, water and other volatile impurities in the papermaking black liquor can be evaporated to obtain concentrated black liquor, and then the concentrated black liquor is subjected to freeze drying. When the concentration is high, the freeze drying is carried out, so that the deterioration of each component in the thick black liquor can be avoided. According to the silicon source and the carbon source provided by the embodiment of the invention, the dried material can keep the original chemical composition and physical properties (such as porous structure, colloidal property and the like) through freeze drying, the freeze drying is different from the common heat drying, the moisture in the material is basically sublimated on the surface of a frozen solid below 0 ℃ for drying, and the material is left in an ice shelf during freezing. Therefore, the dried product has the advantages of unchanged volume, looseness and porosity, and not only can the original properties be kept unchanged, but also the product can be more conveniently ground into nano-grade powder.
Step 402: heating the nanoscale powder from room temperature to 400-600 ℃ at a heating rate of 1-5 ℃/min in a positive pressure argon environment, preserving heat for 0.5-1.5 h, then heating to 900-1000 ℃ at 1-5 ℃/min, preserving heat for 1-2 h, then continuously heating to 1200-1400 ℃ at 3-10 ℃/min, and preserving heat for 1-2 h to obtain the porous SiC nanomaterial.
In the embodiment of the invention, organic matters such as lignin, cellulose and the like in the papermaking black liquor contain a large amount of carbon elements, and as a direct carbonization method (namely a high-temperature pyrolysis method) is used, chemical bonds of the large amount of carbon elements in the papermaking black liquor are destroyed by heat energy under an anaerobic condition, so that the porous carbon material is prepared by thermal decomposition. Meanwhile, the nano-scale powder is heated and insulated for three times, so that the papermaking black liquor can be carbonized more fully. At the moment, the silicon simple substance is dispersed in the carbon simple substance, and the volume change of the simple substance carbon in the charging and discharging process is small, so that the volume expansion of the silicon in the discharging process can be buffered by using the carbon simple substance, the silicon-based electrode material is prevented from generating cracks until being powdered, the contact between the electrode material and a current collector is enhanced, the energy attenuation of a metal electrode plate is slowed down, and the battery capacity is improved. The extrusion of the electrode plate caused by the internal stress of the battery due to volume expansion can be avoided, and the risk of electrode plate fracture is reduced. In addition, the simple substance carbon provided by the embodiment of the application has better conductivity, and can improve the electronic conductivity of the electrode material, so that the cycle stability of the battery is improved.
In an alternative manner, fig. 5 shows a flow chart of the preparation of the carbon paper-based skeleton according to the embodiment of the present invention, and as shown in fig. 5, the preparation method of the carbon paper-based skeleton according to the embodiment of the present invention includes:
step 501: polyethylene oxide and polyvinyl alcohol are added to the chopped carbon fibers to form a first mixed slurry.
Illustratively, chopped carbon fibers comprising carbon fibers and water-soluble fibers are mixed with water, and then polyethylene oxide (PEO) and polyvinyl alcohol (PVA) are sequentially added to obtain a first mixed slurry. According to the embodiment of the invention, the polyethylene oxide and the polyvinyl alcohol are added into the water containing the chopped carbon fibers, so that the adhesion and the film forming property of the fibers can be improved. Meanwhile, the polyethylene oxide can be used as a dispersing agent in the slurry to uniformly disperse the carbon fibers and the water-soluble fibers, and the polyvinyl alcohol can also be used as a surface sizing agent, so that the wear resistance, folding resistance and tearing resistance of the carbon paper can be improved, and the glossiness, smoothness and printing adaptability of the carbon paper can also be improved. Therefore, the carbon paper with uniformly dispersed fibers and good glossiness can be prepared by adding the polyethylene oxide and the polyvinyl alcohol into the chopped carbon fibers in the embodiment of the invention.
The mass percentage of the chopped carbon fibers in the first mixed slurry is 1-2%, the addition amount of PEO is 0.1-0.5% of the mixed slurry, and the addition amount of PVA is 0.1-0.3% of the mixed slurry.
Step 502: and (4) papermaking the first mixed slurry into carbon paper.
For example: and (3) making the first mixed slurry into a wet paper web, and then drying to obtain the carbon paper.
Step 503: and (3) dipping the carbon paper in thermosetting phenolic resin added with a toughening agent, and then carrying out hot-pressing curing to obtain the carbon paper-based framework.
Illustratively, the carbon paper is soaked in thermosetting phenolic resin added with a toughening agent, and then hot-pressing curing is carried out, wherein the curing temperature can be 120-180 ℃, the curing time can be 3-8 min, and the curing pressure can be 1-6 MPa. The toughening agent can comprise at least one of carboxyl nitrile rubber, liquid nitrile rubber, polyvinyl butyral, polyether sulfone and polyphenylene ether ketone. In the embodiment of the invention, the toughening agent is added into the thermosetting phenolic resin, so that the elongation and brittleness of the thermosetting phenolic resin can be improved, and cracks are not easy to generate when the bonding part bears external force, so that the thermosetting phenolic resin is prevented from cracking, and the charcoal paper-based framework with better mechanical strength is prepared. Meanwhile, the phenolic resin has good bonding effect, can be compatible with various organic and inorganic fillers, and also has strong interface bonding capability. Furthermore, the composite layer in the embodiment of the present invention contains porous SiC and metal ions crosslinked together. Therefore, the thermosetting phenolic resin on the surface of the carbon paper-based framework can have good bonding effect and strong interface bonding capability with the composite layer, so that the structure of the electrode material is more stable.
In an alternative mode, the electrode material provided by the embodiment of the invention is soaked in polytetrafluoroethylene containing a conductive agent, and then the polytetrafluoroethylene is placed into a sintering furnace for sintering, wherein the sintering temperature is 300-400 ℃, and the electrode plate of the ion battery is obtained. The conductive agent can comprise at least one of carbon nano tube, acetylene black, carbon black or graphene, and the mass content of the conductive agent is 10-30%.
Therefore, in the electrode material provided by the invention, the composite layer is formed on the surface of the carbon paper-based framework, and the composite layer contains the porous SiC and the metal ions which are crosslinked together, so that the porous SiC and the metal ions can form an alloy with a three-dimensional network structure, and the specific capacity of the electrode material can be improved. Meanwhile, according to the electrode material provided by the embodiment of the application, when the silicon simple substance contained in the porous SiC is dispersed in the carbon simple substance contained in the porous SiC, the volume change is small in the charging and discharging process of the simple substance carbon, so that the volume expansion of the silicon in the discharging process can be buffered by using the carbon simple substance, the silicon-based electrode material is prevented from generating cracks until being powdered, the contact between the electrode material and a current collector is enhanced, the energy attenuation of a metal electrode plate is slowed down, and the battery capacity is improved. The extrusion of the electrode plate caused by the internal stress of the battery due to volume expansion can be avoided, and the risk of electrode plate fracture is reduced. In addition, the simple substance carbon provided by the embodiment of the application has better conductivity, and can improve the electronic conductivity of the electrode material, so that the cycle stability of the battery is improved.
In order to verify the effect of the electrode material provided by the embodiment of the present invention, the embodiment of the present invention is demonstrated by comparing the embodiment with the comparative example.
Example one
The embodiment of the invention provides an electrode material which comprises a carbon paper-based framework and a composite layer formed on the surface of the carbon paper-based framework.
The preparation method of the electrode material provided by the first embodiment of the invention comprises the following steps:
firstly, preparing a porous SiC nano material: evaporating and concentrating the papermaking black liquor in an oven at 90 ℃ to obtain concentrated black liquor, and then freezing and drying. Grinding the freeze-dried solid into nanoscale powder, heating the nanoscale powder to 400 ℃ at a heating rate of 3 ℃/min under a positive pressure argon environment, preserving heat for 1h, then heating to 900 ℃ at a heating rate of 3 ℃/min, and preserving heat for 1.5 h; and finally, continuously heating to 1200 ℃ at the speed of 5 ℃/min, and preserving the heat for 2 hours to obtain the porous SiC nano material.
Step two, preparing a composite material dispersion liquid: according to mass percentage, 40% of porous SiC nano material and 55% of Ge (SO) 2 ) 2 And mixing and stirring the solution and 5% ammonium carbonate to obtain a mixed solution, and adjusting the pH value to be neutral by using a NaOH solution to obtain the composite material dispersion liquid.
Step three, preparing a carbon paper base framework: according to the mass percentage, 85% of carbon fiber and 15% of water-soluble fiber are added with water and mixed evenly, and then polyoxyethylene and polyvinyl alcohol are added in sequence to obtain mixed slurry. Wherein, the carbon fiber and the water-soluble fiber account for 1 percent of the mixed slurry, the polyoxyethylene accounts for 0.2 percent of the mixed slurry, and the polyvinyl alcohol accounts for 0.2 percent of the mixed slurry in percentage by mass. And then, papermaking the mixed pulp to form a wet paper web, drying to obtain a carbon paper base paper, soaking the carbon paper base paper in thermosetting phenolic resin added with 1% of polyether sulfone, and then performing hot-pressing curing to obtain the carbon paper base framework. Wherein the hot-press curing temperature is 120 ℃, the hot-press curing time is 5min, and the hot-press curing pressure is 2 MPa.
Fourthly, preparing an electrode material: and (3) soaking the carbon paper-based framework in the composite layer dispersion liquid, placing the mixture into a reaction container for hydrothermal reaction, wherein the reaction time is 30min, the reaction temperature is 200 ℃, and then taking out and drying the mixture to obtain the SiC-Ge alloy layer electrode material.
Step five, preparing an electrode slice: and (3) soaking the SiC-Ge alloy layer electrode material in polytetrafluoroethylene containing 10% of carbon nano tubes, and then putting the polytetrafluoroethylene into a sintering furnace for sintering at the sintering temperature of 350 ℃ to obtain the electrode plate of the ion battery.
Example two
The embodiment of the invention provides an electrode material which comprises a carbon paper-based framework and a composite layer formed on the surface of the carbon paper-based framework.
The preparation method of the electrode material provided by the embodiment of the invention comprises the following steps:
firstly, preparing a porous SiC nano material: evaporating and concentrating the papermaking black liquor in an oven at 105 ℃ to obtain concentrated black liquor, and then performing freeze drying. Grinding the freeze-dried solid into nanoscale powder, heating the nanoscale powder to 450 ℃ at a heating rate of 3 ℃/min under a positive pressure argon environment, preserving heat for 1h, then heating to 950 ℃ at 3 ℃/min, and preserving heat for 1.5 h; and finally, continuously heating to 1200 ℃ at the speed of 5 ℃/min, and preserving the heat for 2 hours to obtain the porous SiC nano material.
Step two, preparing a composite material dispersion liquid: according to the mass percentage, 45 percent of porous SiC nano material and 50 percent of SnCl 2 And mixing and stirring the solution and 5% ammonium bicarbonate to obtain a mixed solution, and adjusting the pH value to be neutral by using an HCl solution to obtain the composite material dispersion liquid.
Step three, preparing a carbon paper base framework: according to the mass percentage, 85% of carbon fiber and 15% of water-soluble fiber are added with water and mixed evenly, and then polyoxyethylene and polyvinyl alcohol are added in sequence to obtain mixed slurry. Wherein, the carbon fiber and the water-soluble fiber account for 1 percent of the mixed slurry, the polyoxyethylene accounts for 0.2 percent of the mixed slurry, and the polyvinyl alcohol accounts for 0.2 percent of the mixed slurry in percentage by mass. And then, papermaking the mixed pulp to form a wet paper web, drying to obtain a carbon paper base paper, soaking the carbon paper base paper in thermosetting phenolic resin added with 1% of polyphenylene ether ketone, and then performing hot-pressing curing to obtain the carbon paper base framework. Wherein the hot-press curing temperature is 120 ℃, the hot-press curing time is 5min, and the hot-press curing pressure is 3 MPa.
Fourthly, preparing an electrode material: and (3) soaking the carbon paper-based framework in the composite layer dispersion liquid, placing the mixture into a reaction container for hydrothermal reaction, wherein the reaction time is 30min, the reaction temperature is 250 ℃, and then taking out and drying the mixture to obtain the SiC-Sn alloy layer electrode material.
Step five, preparing an electrode slice: and (3) soaking the SiC-Sn alloy layer electrode material in polytetrafluoroethylene containing 10% of carbon nano tubes, and then putting the polytetrafluoroethylene into a sintering furnace for sintering at the sintering temperature of 350 ℃ to obtain the electrode plate of the ion battery.
EXAMPLE III
The embodiment of the invention provides an electrode material which comprises a carbon paper-based framework and a composite layer formed on the surface of the carbon paper-based framework.
The preparation method of the electrode material provided by the third embodiment of the invention comprises the following steps:
step one, preparing a porous SiC nano material: evaporating and concentrating the papermaking black liquor in an oven at 105 ℃ to obtain concentrated black liquor, and then performing freeze drying. Grinding the freeze-dried solid into nanoscale powder, heating the nanoscale powder to 450 ℃ at a heating rate of 3 ℃/min under a positive pressure argon environment, preserving heat for 1h, then heating to 950 ℃ at 3 ℃/min, and preserving heat for 1.5 h; and finally, continuously heating to 1300 ℃ at the speed of 5 ℃/min, and preserving the heat for 1.5h to prepare the porous SiC nano material.
Step two, preparing a composite material dispersion liquid: according to the mass percentage, 45 percent of porous SiC nanometer material and 50 percent of PbCl are added 2 And mixing and stirring the solution and 5% ammonium dihydrogen phosphate to obtain a mixed solution, and adjusting the pH value to be neutral by using an HCl solution to obtain the composite material dispersion liquid.
Step three, preparing a carbon paper base framework: according to the mass percentage, water is added into 80% of carbon fiber and 20% of water-soluble fiber and evenly mixed, and then polyoxyethylene and polyvinyl alcohol are sequentially added to obtain mixed slurry. Wherein, the carbon fiber and the water-soluble fiber account for 1 percent of the mixed pulp, the polyoxyethylene accounts for 0.2 percent of the mixed pulp, and the polyvinyl alcohol accounts for 0.3 percent of the mixed pulp according to the mass percentage of the mixed pulp. And then, papermaking the mixed pulp to form a wet paper web, drying to obtain a carbon paper base paper, soaking the carbon paper base paper in thermosetting phenolic resin added with 1% of liquid nitrile butadiene rubber, and then performing hot pressing and curing to obtain the carbon paper base framework. Wherein the hot-press curing temperature is 120 ℃, the hot-press curing time is 5min, and the hot-press curing pressure is 3 MPa.
Fourthly, preparing an electrode material: and (3) soaking the carbon paper-based framework in the composite layer dispersion liquid, placing the mixture into a reaction container for hydrothermal reaction, wherein the reaction time is 30min, the reaction temperature is 300 ℃, and then taking out and drying the mixture to obtain the SiC-Pb alloy layer electrode material.
Step five, preparing an electrode slice: and (3) dipping the SiC-Pb alloy layer electrode material in polytetrafluoroethylene containing 10% of acetylene black, and then putting the polytetrafluoroethylene into a sintering furnace for sintering at the sintering temperature of 350 ℃ to obtain the electrode plate of the ion battery.
Example four
The embodiment of the invention provides an electrode material which comprises a carbon paper-based framework and a composite layer formed on the surface of the carbon paper-based framework.
The preparation method of the electrode material provided by the fourth embodiment of the invention comprises the following steps:
firstly, preparing a porous SiC nano material: evaporating and concentrating the papermaking black liquor in an oven at 105 ℃ to obtain concentrated black liquor, and then performing freeze drying. Grinding the freeze-dried solid into nanoscale powder, heating the nanoscale powder to 450 ℃ at a heating rate of 3 ℃/min under a positive pressure argon environment, preserving heat for 1h, then heating to 950 ℃ at 3 ℃/min, and preserving heat for 1.5 h; and finally, continuously heating to 1300 ℃ at the speed of 5 ℃/min, and preserving the heat for 1.5h to prepare the porous SiC nano material.
Step two, preparing a composite material dispersion liquid: 50 percent of porous SiC nano material and 45 percent of SbCl by mass percentage 2 And mixing and stirring the solution and 5% ammonium dihydrogen carbonate to obtain a mixed solution, and adjusting the pH value to be neutral by using an HCl solution to obtain the composite material dispersion liquid.
Step three, preparing a carbon paper base framework: according to the mass percentage, 90% of carbon fiber and 10% of water-soluble fiber are added with water and mixed evenly, and then polyoxyethylene and polyvinyl alcohol are added in sequence to obtain mixed slurry. Wherein, the carbon fiber and the water-soluble fiber account for 1 percent of the mixed pulp, the polyoxyethylene accounts for 0.2 percent of the mixed pulp, and the polyvinyl alcohol accounts for 0.3 percent of the mixed pulp according to the mass percentage of the mixed pulp. And then, papermaking the mixed pulp to form a wet paper web, drying to obtain a carbon paper base paper, soaking the carbon paper base paper in thermosetting phenolic resin added with 1% polyvinyl butyral, and then performing hot pressing and curing to obtain the carbon paper base framework. Wherein the hot-press curing temperature is 120 ℃, the hot-press curing time is 6min, and the hot-press curing pressure is 2 MPa.
Fourthly, preparing an electrode material: and (3) soaking the carbon paper-based framework in the composite layer dispersion liquid, placing the mixture into a reaction container for hydrothermal reaction, wherein the reaction time is 30min, the reaction temperature is 300 ℃, and then taking out and drying the mixture to obtain the SiC-Sb alloy layer electrode material.
Step five, preparing an electrode slice: and (3) soaking the SiC-Sb alloy layer electrode material in polytetrafluoroethylene containing 12% of carbon black, and then putting the polytetrafluoroethylene into a sintering furnace for sintering at the sintering temperature of 350 ℃ to obtain the electrode plate of the ion battery.
EXAMPLE five
The embodiment of the invention provides an electrode material which comprises a carbon paper-based framework and a composite layer formed on the surface of the carbon paper-based framework.
The preparation method of the electrode material provided by the fifth embodiment of the invention comprises the following steps:
firstly, preparing a porous SiC nano material: evaporating and concentrating the papermaking black liquor in an oven at 105 ℃ to obtain concentrated black liquor, and then performing freeze drying. Grinding the freeze-dried solid into nanoscale powder, heating the nanoscale powder to 450 ℃ at a heating rate of 3 ℃/min under a positive pressure argon environment, preserving heat for 1h, then heating to 950 ℃ at 3 ℃/min, and preserving heat for 1.5 h; and finally, continuously heating to 1300 ℃ at the speed of 5 ℃/min, and preserving the heat for 1.5h to prepare the porous SiC nano material.
Step two, preparing a composite material dispersion liquid: 50 percent of porous SiC nano material and 20 percent of BiCl according to mass percentage 3 20% of SbCl 2 And mixing and stirring the solution, 5% ammonium dihydrogen carbonate and 5% ammonium carbonate to obtain a mixed solution, and adjusting the pH value to be neutral by using an HCl solution to obtain the composite material dispersion liquid.
Step three, preparing a carbon paper base framework: according to the mass percentage, water is added into 100 percent of carbon fiber and evenly mixed, and then polyoxyethylene and polyvinyl alcohol are sequentially added to obtain mixed slurry. Wherein, the carbon fiber and the water-soluble fiber account for 2 percent of the mixed slurry, the polyethylene oxide accounts for 0.5 percent of the mixed slurry, and the polyvinyl alcohol accounts for 0.3 percent of the mixed slurry. Then, the mixed pulp is made into wet paper, the wet paper is dried to obtain raw paper of the carbon paper, the raw paper of the carbon paper is soaked in thermosetting phenolic resin added with 0.5 percent of polyvinyl butyral and 0.5 percent of liquid nitrile butadiene rubber, and then hot pressing solidification is carried out to obtain the carbon paper base framework. Wherein the hot-press curing temperature is 120 ℃, the hot-press curing time is 6min, and the hot-press curing pressure is 2 MPa.
Fourthly, preparing an electrode material: and (3) soaking the carbon paper-based framework in the composite layer dispersion liquid, placing the mixture into a reaction container for hydrothermal reaction, wherein the reaction time is 30min, the reaction temperature is 300 ℃, and then taking out and drying the mixture to obtain the SiC-Bi alloy layer electrode material.
Step five, preparing an electrode slice: and (3) soaking the SiC-Bi alloy layer electrode material in polytetrafluoroethylene containing 12% of carbon black, and then putting the polytetrafluoroethylene into a sintering furnace for sintering at the sintering temperature of 350 ℃ to obtain the electrode plate of the ion battery.
EXAMPLE six
The embodiment of the invention provides an electrode material which comprises a carbon paper-based framework and a composite layer formed on the surface of the carbon paper-based framework.
The preparation method of the electrode material provided by the fifth embodiment of the invention comprises the following steps:
firstly, preparing a porous SiC nano material: evaporating and concentrating the papermaking black liquor in an oven at 105 ℃ to obtain concentrated black liquor, and then performing freeze drying. Grinding the freeze-dried solid into nanoscale powder, heating the nanoscale powder to 450 ℃ at a heating rate of 3 ℃/min under a positive pressure argon environment, preserving heat for 1h, then heating to 950 ℃ at 3 ℃/min, and preserving heat for 1.5 h; and finally, continuously heating to 1300 ℃ at the speed of 5 ℃/min, and preserving the heat for 1.5h to prepare the porous SiC nano material.
Step two, preparing a composite material dispersion liquid: according to the mass percentage, 20 percent of porous SiC nanometer material and 75 percent of FeCl 3 And mixing and stirring the solution and 5% ammonium dihydrogen carbonate to obtain a mixed solution, and adjusting the pH value to be neutral by using an HCl solution to obtain the composite material dispersion liquid.
Step three, preparing a carbon paper base framework: according to the mass percentage, 85% of carbon fiber and 15% of water-soluble fiber are added with water and mixed evenly, and then polyoxyethylene and polyvinyl alcohol are added in sequence to obtain mixed slurry. Wherein, the carbon fiber and the water-soluble fiber account for 1 percent of the mixed pulp, the polyoxyethylene accounts for 0.1 percent of the mixed pulp, and the polyvinyl alcohol accounts for 0.1 percent of the mixed pulp by mass percentage. And then, making the mixed pulp into a wet paper web, drying to obtain raw carbon paper, soaking the raw carbon paper in thermosetting phenolic resin added with 1% of polyvinyl butyral, and performing hot pressing solidification to obtain the carbon paper base framework. Wherein the hot-press curing temperature is 120 ℃, the hot-press curing time is 6min, and the hot-press curing pressure is 2 MPa.
Step four, preparing an electrode material: and (3) soaking the carbon paper-based framework in the composite layer dispersion liquid, placing the mixture into a reaction container for hydrothermal reaction, wherein the reaction time is 30min, the reaction temperature is 300 ℃, and then taking out and drying the mixture to obtain the SiC-Fe alloy layer electrode material.
Step five, preparing an electrode slice: and (3) soaking the SiC-Fe alloy layer electrode material in polytetrafluoroethylene containing 12% of carbon black, and then putting the polytetrafluoroethylene into a sintering furnace for sintering at the sintering temperature of 350 ℃ to obtain the electrode plate of the ion battery.
Comparative example 1
Comparative example of the present invention provides an electrode material that does not contain the composite layer of the example of the present invention.
The preparation method of the electrode material provided by the first comparative example of the invention comprises the following steps:
step one, preparing a porous SiC nano material: evaporating and concentrating the papermaking black liquor in an oven at 105 ℃ to obtain concentrated black liquor, and then performing freeze drying. Grinding the freeze-dried solid into nanoscale powder, heating the nanoscale powder to 500 ℃ at a heating rate of 3 ℃/min under a positive pressure argon environment, preserving heat for 1h, then heating to 950 ℃ at 3 ℃/min, and preserving heat for 1.5 h; and finally, continuously heating to 1300 ℃ at the speed of 5 ℃/min, and preserving the heat for 1.5 hours to obtain the porous SiC nano material.
Step two, preparing a carbon paper base framework: according to the mass percentage, 90% of carbon fiber and 10% of water-soluble fiber are added with water and mixed evenly, and then polyoxyethylene and polyvinyl alcohol are added in sequence to obtain mixed slurry. Wherein, the carbon fiber and the water-soluble fiber account for 1 percent of the mixed pulp, the polyoxyethylene accounts for 0.2 percent of the mixed pulp, and the polyvinyl alcohol accounts for 0.3 percent of the mixed pulp according to the mass percentage of the mixed pulp. And then, making the mixed pulp into a wet paper web, and drying to obtain the carbon paper base paper.
Thirdly, preparing a load SiC layer: and mixing the porous SiC nano material in thermosetting phenolic resin added with 1% of polyether sulfone to obtain a mixed solution, then soaking the carbon paper base paper in the mixed solution, and performing hot-pressing solidification to obtain the SiC-layer-loaded carbon paper electrode material. Wherein the hot-press curing temperature is 120 ℃, the hot-press curing time is 6min, and the hot-press curing pressure is 2 MPa.
Step four, preparing an electrode plate: and (3) soaking the SiC-loaded carbon paper electrode material in polytetrafluoroethylene containing 12% of carbon nano tubes, and then putting the polytetrafluoroethylene into a sintering furnace for sintering at 350 ℃ to obtain the electrode plate of the ion battery.
Comparative example No. two
Comparative example two of the present invention provides an electrode material that does not contain the composite layer and carbon paper-based skeleton of the examples of the present invention.
The preparation method of the electrode material provided by the comparative example of the invention comprises the following steps:
firstly, preparing a porous SiC nano material: evaporating and concentrating the papermaking black liquor in an oven at 105 ℃ to obtain concentrated black liquor, and then performing freeze drying. Grinding the freeze-dried solid into nanoscale powder, heating the nanoscale powder to 500 ℃ at a heating rate of 3 ℃/min under a positive pressure argon environment, preserving heat for 1h, then heating to 950 ℃ at 3 ℃/min, and preserving heat for 1.5 h; and finally, continuously heating to 1300 ℃ at the speed of 5 ℃/min, and preserving the heat for 1.5h to prepare the porous SiC nano material.
Step two, preparing an electrode slice: mixing 55% of porous SiC nano material, 25% of carbon fiber, 10% of carbon nano tube and 10% of thermosetting resin according to mass percentage, uniformly stirring by a machine, and pressing into a sheet shape by a press roller machine to obtain the negative plate of the ion battery.
The present inventors tested data on electrode materials prepared in examples and comparative examples, wherein electrode materials comprising a carbon paper-based skeleton and a composite layer formed on the surface of the carbon paper-based skeleton were used in all of examples one to six, and comparative example one did not contain the composite layer in examples of the present invention, and comparative example two did not contain the composite layer in examples of the present invention and did not contain the carbon paper-based skeleton in examples of the present invention, as compared with examples of the present invention. The test results of the examples and comparative examples are given in the following table:
specific capacity (mAh/g) First efficiency (%) 2C/0.2C retention (%) Charge-discharge cycle performance (500 times)
Example 1 231 84 49 Good cycle performance
Example 2 240 85 50 Good cycle performance
Example 3 228 84 48 Good cycle performance
Example 4 237 83 47 Good cycle performance
Example 5 238 84 50 Good cycle performance
Example 6 235 85 51 Good cycle performance
Comparative example 1 198 76 22 Poor cycle performance
Comparative example 2 212 69 27 Poor cycle performance
As can be seen from the above table, the electrode materials prepared in the first to sixth examples of the present invention use a carbon paper-based skeleton and a composite layer formed on the surface of the carbon paper-based skeleton, the electrode material prepared in the first comparative example does not contain the composite layer in the examples of the present invention, and only contains carbon paper base paper, and the electrode material prepared in the second comparative example does not contain carbon paper base paper nor composite layer. The specific capacity and the charging cycle number of the electrode material are obviously greater than those of the first comparative example and the second comparative example, so that the specific capacity of the negative electrode material of the ion battery is improved, the cycle stability of the ion battery is also improved and the safety of the battery is improved under the combined action of the carbon paper-based framework and the composite layer due to the use of the carbon paper-based framework and the composite layer formed on the surface of the carbon paper-based framework.
While the foregoing is directed to embodiments of the present invention, it will be apparent that various modifications and combinations can be made without departing from the spirit and scope of the invention. Accordingly, the specification and figures are merely exemplary of the invention as defined in the appended claims and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. Any person skilled in the art can easily conceive of changes or substitutions within the technical scope of the present disclosure, and all such changes or substitutions are included in the scope of the present disclosure. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (12)

1. An electrode material, comprising: the composite layer contains porous SiC and metal ions which are crosslinked together, and a silicon simple substance contained in the porous SiC is dispersed in a carbon simple substance contained in the porous SiC.
2. The electrode material of claim 1, wherein the porous SiC has a nanoporous network structure.
3. The electrode material according to claim 1, wherein the mass ratio of the porous SiC to the metal ions is (20-50): (40-75).
4. The electrode material of claim 1, wherein the metal ions comprise at least one of P-block metal ions and transition metal ions;
the P region metal ions comprise at least one of germanium ions, tin ions, lead ions, antimony ions and bismuth ions;
the transition metal ions include at least one of chromium ions, manganese ions, iron ions, cobalt ions, nickel ions, copper ions, zinc ions, palladium ions, silver ions, platinum ions, gold ions, and mercury ions.
5. The electrode material according to any one of claims 1 to 4, wherein the carbon paper-based skeleton is a carbonized material formed by chopped carbon fibers including carbon fibers and water-soluble fibers, a thermosetting phenolic resin is formed on the surface of the carbon paper-based skeleton, and the chopped carbon fibers include, by mass, 85 to 100 parts of carbon fibers and 0 to 15 parts of water-soluble carbon fibers;
the diameter of carbon fiber is 5um ~ 10um, the length of carbon fiber is 5mm ~ 10mm, water-soluble fibrous diameter 7um ~ 15um, water-soluble fibrous length is 5mm ~ 10 mm.
6. The electrode material as claimed in claim 5, wherein the charcoal paper-based skeleton further comprises polyethylene oxide and polyvinyl alcohol, and the mass ratio of the chopped carbon fibers to the polyethylene oxide to the polyvinyl alcohol is (1-2): (0.1 to 0.5) and (0.1 to 0.3).
7. A method for preparing the electrode material according to any one of claims 1 to 6, comprising:
mixing the porous SiC nano material with metal ions by using an initiator to obtain a composite material;
preparing a carbon paper-based framework by using short carbon fibers;
and forming the composite material on the surface of the carbon paper-based framework to form a composite layer on the surface of the carbon paper-based framework, so as to obtain the electrode material.
8. The method for preparing an electrode material according to claim 7, wherein before the porous SiC nanomaterial is mixed with metal ions by using the initiator to obtain the composite material, the method for preparing an electrode material further comprises:
mixing a silicon source and a carbon source, and grinding the obtained mixture into nanoscale powder;
and (2) heating the nanoscale powder from room temperature to 400-600 ℃ at a heating rate of 1-5 ℃/min in a positive pressure argon environment, preserving heat for 0.5-1.5 h, then heating to 900-1000 ℃ at 1-5 ℃/min, preserving heat for 1-2 h, then continuously heating to 1200-1400 ℃ at 3-10 ℃/min, and preserving heat for 1-2 h to obtain the porous SiC nanomaterial.
9. The method for preparing the electrode material according to claim 7, wherein the preparing the carbon paper-based skeleton by using the chopped carbon fibers comprises the following steps:
adding polyoxyethylene and polyvinyl alcohol to the chopped carbon fibers to form a first mixed slurry;
making the first mixed slurry into carbon paper;
and (3) dipping the carbon paper in thermosetting phenolic resin added with a toughening agent, and then carrying out hot-pressing curing to obtain the carbon paper-based framework.
10. The method for preparing an electrode material according to claim 7, wherein the step of forming the composite material on the surface of the carbon paper-based skeleton to form a composite layer on the surface of the carbon paper-based skeleton to obtain the electrode material comprises the following steps:
and dipping the carbon paper-based framework in the dispersion liquid of the composite material, and then carrying out hydrothermal reaction to form the composite material on the surface of the carbon paper-based framework and form a composite layer on the surface of the carbon paper-based framework to obtain the electrode material.
11. An electrode sheet, characterized by comprising the electrode material according to any one of claims 1 to 6.
12. A battery comprising the electrode material according to any one of claims 1 to 6.
CN202210774823.4A 2022-07-01 2022-07-01 Electrode material, preparation method, electrode plate and battery Active CN115050925B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210774823.4A CN115050925B (en) 2022-07-01 2022-07-01 Electrode material, preparation method, electrode plate and battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210774823.4A CN115050925B (en) 2022-07-01 2022-07-01 Electrode material, preparation method, electrode plate and battery

Publications (2)

Publication Number Publication Date
CN115050925A true CN115050925A (en) 2022-09-13
CN115050925B CN115050925B (en) 2023-09-01

Family

ID=83165709

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210774823.4A Active CN115050925B (en) 2022-07-01 2022-07-01 Electrode material, preparation method, electrode plate and battery

Country Status (1)

Country Link
CN (1) CN115050925B (en)

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004182512A (en) * 2002-12-02 2004-07-02 Showa Denko Kk Carbon material, its manufacturing method and use
CN1913200A (en) * 2006-08-22 2007-02-14 深圳市贝特瑞电子材料有限公司 Silicon carbone compound negative polar material of lithium ion battery and its preparation method
JP2007109631A (en) * 2005-09-15 2007-04-26 Nissan Motor Co Ltd Electrode for battery
CN101740766A (en) * 2008-11-21 2010-06-16 比亚迪股份有限公司 Cathode active material, preparation method thereof and lithium battery using same
CN102479939A (en) * 2010-11-25 2012-05-30 上海交通大学 Electrode used in lithium ion battery, and manufacturing method thereof
JP2013171793A (en) * 2012-02-22 2013-09-02 Mitsubishi Chemicals Corp Negative electrode material for nonaqueous electrolyte secondary battery, method for producing the same, negative electrode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery
CN104681797A (en) * 2015-02-09 2015-06-03 江苏中兴派能电池有限公司 Method for preparing silicon-carbon composite anode and lithium ion battery
US10424786B1 (en) * 2018-12-19 2019-09-24 Nexeon Limited Electroactive materials for metal-ion batteries
CN110649236A (en) * 2019-09-24 2020-01-03 中国科学院化学研究所 Porous silicon-carbon composite material and preparation method thereof
CN113964303A (en) * 2021-10-09 2022-01-21 中国科学院深圳先进技术研究院 Silicon composite negative electrode material, preparation method thereof and secondary battery

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004182512A (en) * 2002-12-02 2004-07-02 Showa Denko Kk Carbon material, its manufacturing method and use
JP2007109631A (en) * 2005-09-15 2007-04-26 Nissan Motor Co Ltd Electrode for battery
CN1913200A (en) * 2006-08-22 2007-02-14 深圳市贝特瑞电子材料有限公司 Silicon carbone compound negative polar material of lithium ion battery and its preparation method
CN101740766A (en) * 2008-11-21 2010-06-16 比亚迪股份有限公司 Cathode active material, preparation method thereof and lithium battery using same
CN102479939A (en) * 2010-11-25 2012-05-30 上海交通大学 Electrode used in lithium ion battery, and manufacturing method thereof
JP2013171793A (en) * 2012-02-22 2013-09-02 Mitsubishi Chemicals Corp Negative electrode material for nonaqueous electrolyte secondary battery, method for producing the same, negative electrode for nonaqueous electrolyte secondary battery, and nonaqueous electrolyte secondary battery
CN104681797A (en) * 2015-02-09 2015-06-03 江苏中兴派能电池有限公司 Method for preparing silicon-carbon composite anode and lithium ion battery
US10424786B1 (en) * 2018-12-19 2019-09-24 Nexeon Limited Electroactive materials for metal-ion batteries
CN110649236A (en) * 2019-09-24 2020-01-03 中国科学院化学研究所 Porous silicon-carbon composite material and preparation method thereof
CN113964303A (en) * 2021-10-09 2022-01-21 中国科学院深圳先进技术研究院 Silicon composite negative electrode material, preparation method thereof and secondary battery

Also Published As

Publication number Publication date
CN115050925B (en) 2023-09-01

Similar Documents

Publication Publication Date Title
CN110071292B (en) Preparation method of lithium ion battery positive pole piece and positive pole piece
CN111710874B (en) Solid-state lithium battery, composite negative electrode and preparation method of composite negative electrode
CN110364761B (en) High-energy-density long-circulation lithium iron phosphate battery
CN112687865A (en) Lithium ion battery cathode slurry, preparation method and application thereof
CN112670507A (en) Preparation method of lithium-sulfur battery intermediate layer of metal selenide-loaded carbon nanofiber and lithium-sulfur battery
CN109148841B (en) Lithium-based montmorillonite @ sulfur composite material and preparation method and application thereof
CN113078296B (en) Dry powder coating method of battery pole piece based on phosphate positive electrode material
CN114400307A (en) Tin-carbon composite material and preparation method and application thereof
CN111525139B (en) Graphite paper current collector, negative electrode and preparation method
CN110718680B (en) Lithium manganate battery positive plate and preparation method thereof
CN113285050A (en) Li-M-X-based solid lithium battery anode and preparation method thereof
CN112701255A (en) High-temperature-resistant flexible lithium battery positive pole piece and preparation method thereof
CN115050925B (en) Electrode material, preparation method, electrode plate and battery
CN111446415B (en) Silicon negative plate and preparation method and application thereof
CN115528205A (en) Double-step type pole piece and lithium ion battery
CN114388726B (en) High-magnification thick positive electrode and preparation method thereof
CN110600738B (en) Method for preparing low-temperature lithium ion battery hard carbon negative electrode material
CN114156437A (en) High-area-density lithium battery negative plate, preparation method and lithium battery
CN113889625A (en) Modified hard carbon composite material and preparation method and application thereof
CN114156471A (en) Graphite negative electrode material and preparation method and application thereof
CN112531141A (en) Pole piece for battery and preparation method and application thereof
CN112864364B (en) Positive plate containing high extension layer and lithium ion battery comprising positive plate
CN116374991A (en) Preparation method of sodium ion battery anode material based on resin precursor
CN117727565A (en) Carbonized wood/reduced graphene oxide conductive composite material and preparation method and application thereof
CN116154106A (en) Multilayer composite tin foil negative electrode for sodium ion secondary battery and preparation method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant