CN114597391B - Lithium-rich manganese-based composite single crystal ternary/silicon oxide composite graphite lithium ion battery - Google Patents

Lithium-rich manganese-based composite single crystal ternary/silicon oxide composite graphite lithium ion battery Download PDF

Info

Publication number
CN114597391B
CN114597391B CN202210269445.4A CN202210269445A CN114597391B CN 114597391 B CN114597391 B CN 114597391B CN 202210269445 A CN202210269445 A CN 202210269445A CN 114597391 B CN114597391 B CN 114597391B
Authority
CN
China
Prior art keywords
lithium
graphite
ion battery
lithium ion
slurry
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.)
Active
Application number
CN202210269445.4A
Other languages
Chinese (zh)
Other versions
CN114597391A (en
Inventor
席柳江
张思方
杨红帅
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.)
Anhui Liyuan New Energy Co ltd
Original Assignee
Anhui Liyuan New Energy 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 Anhui Liyuan New Energy Co ltd filed Critical Anhui Liyuan New Energy Co ltd
Priority to CN202210269445.4A priority Critical patent/CN114597391B/en
Publication of CN114597391A publication Critical patent/CN114597391A/en
Application granted granted Critical
Publication of CN114597391B publication Critical patent/CN114597391B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

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
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • 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
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/621—Binders
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/625—Carbon or graphite
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The invention discloses a lithium-rich manganese-based composite single crystal ternary/silicon monoxide composite graphite lithium ion battery, relates to the technical field of composite graphite lithium batteries, and is used for solving the technical problem that graphite materials need to be modified in the prior art so as to improve the multiplying power, cycle life and energy density comprehensive performance of the lithium ion battery; according to the lithium ion battery, the positive electrode is made of a high-capacity manganese-rich lithium-nickel-cobalt-manganese ternary composite material, the negative electrode is made of a tin oxide quantum dot modified graphite material, so that the positive electrode and the negative electrode have high specific capacity density and conductivity, the lithium supplement additive is added into the positive electrode and the negative electrode, the first coulombic efficiency of the lithium ion battery is improved, the conductivity is improved due to the addition of the conductive agent, the rate capability of the battery is better, and the lithium ion battery has good safety, rate capability, cycle life and energy density.

Description

Lithium-rich manganese-based composite monocrystal ternary/silicon oxide composite graphite lithium ion battery
Technical Field
The invention relates to the technical field of composite graphite lithium batteries, in particular to a lithium-rich manganese-based composite single crystal ternary/silicon oxide composite graphite lithium ion battery.
Background
The main components of the lithium ion battery are a positive electrode, a negative electrode, a diaphragm and electrolyte. The positive electrode of the current lithium ion power battery generally adopts spinel LiMn 2 O 4 Or nickel-based layered oxide, the negative electrode is mainly graphite, and the electrolyte contains LiPF 6 An organic carbonate solution of (a). The energy density of lithium ion batteries depends to a great extent on the negative electrode material, and from the commercialization of lithium ion batteries to the present, the most mature and widely used negative electrode material is carbon material, and most of the negative electrode material is still graphite. The graphite has a six-membered ring carbon network layered structure with Sp between carbon carbons 2 Hybrid, the layers are connected by molecular force. Compared with artificial graphite, natural graphite has many advantages, its cost is low, crystallization degree is high, purification, pulverization and classification techniques are mature, charging and discharging voltage platform is low, and theoretical specific capacity is high.
The prior art (CN 113224457A) discloses a high-temperature high-power lithium battery and an application thereof, wherein the lithium battery comprises a positive electrode, a negative electrode, a diaphragm and electrolyte, and the diaphragm comprises an organic microporous substrate, a ceramic coating layer and a high-temperature resistant coating layer; the ceramic coating layer is attached to one side or two sides of the organic microporous substrate, and the high-temperature-resistant coating layer continuously coats the surface of the ceramic coating layer and the inner wall of the hole and comprises a high-temperature-resistant polymer and a curing cross-linking agent, wherein the high-temperature-resistant polymer comprises phenolic resin, urea resin, polyimide or epoxy resin. The lithium battery can stably circulate for a long time at a high temperature of 70-200 ℃, has wide application prospects in the fields of development and utilization of underground resources such as petroleum and natural gas, mine drilling and the like, and can stably circulate for a long time under the condition of output power of 8-20 kw to realize safe work. The following technical problems are found to exist: although the negative electrode adopts a graphite material, the graphite material still needs to be modified to improve the comprehensive properties of the lithium ion battery, such as multiplying power, cycle life, energy density and the like.
A solution is now proposed to address the technical drawback in this respect.
Disclosure of Invention
The invention aims to provide a lithium-rich manganese-based composite single crystal ternary/silicon monoxide composite graphite lithium ion battery, which is used for solving the technical problem that although a graphite material is adopted as a negative electrode in the prior art, the graphite material still needs to be modified to improve the comprehensive properties of the lithium ion battery, such as the rate multiplication, the cycle life, the energy density and the like.
The purpose of the invention can be realized by the following technical scheme:
the lithium-rich manganese-based composite single-crystal ternary/silicon monoxide composite graphite lithium ion battery is assembled by sequentially placing a positive pole piece, a diaphragm, a negative pole piece and the diaphragm from top to bottom, assembling the diaphragm and the positive and negative pole pieces in a winding or lamination mode, adding a conductive agent and a lithium supplement additive into the positive and negative pole pieces, then injecting an electrolyte, packaging and aging to obtain a battery cell, and obtaining the lithium ion battery pack by connecting the battery cells in series or in parallel;
wherein, the positive electrode adopts high-capacity rich manganese lithium and nickel cobalt manganeseThe negative electrode of the ternary composite material is made of a graphite material modified by tin oxide quantum dots, the diaphragm is made of an alumina or boehmite ceramic diaphragm, the conductive agent is a mixture of carbon nanotubes and acetylene black, and the electrolyte is high-pressure electrolyte; the lithium supplement additive is Li 0.79 Ni 1.21 O 2 Lithium, Li 3, 4-dihydroxybenzonitrile 2 O-Li 2/3 Mn 1/3 O 5/6 And lithium silicide or a mixture of both.
Further, the preparation method of the tin oxide quantum dot modified graphite material comprises the following steps:
uniformly mixing a silica matrix and absolute ethyl alcohol, and performing wet ball milling to obtain first slurry with the particle size of 0.5-2 mu m; mixing glucose, stannous chloride and water, and performing wet ball milling to obtain a second slurry with a solid content of 20-30% and a particle size of 0.1-1.6 microns;
mixing the first slurry and the second slurry according to a mass ratio of 1: 1.5-2, uniformly mixing to obtain mixed slurry, adding graphite and aluminum tert-butoxide into the mixed slurry, uniformly stirring, and adding a water-based adhesive to adjust the viscosity of the mixed system to 600-800 mPa & S to obtain a mixed material;
introducing the mixed material into a spray dryer for spray drying, and keeping the air inlet temperature at 130-150 ℃ and the air exhaust temperature at 70-80 ℃ to obtain dry powder;
feeding the dried powder into a tube furnace, heating to 250-300 ℃ under the protection of inert gas, and preserving heat for 20-30 min; and heating to 900-1100 ℃, and calcining for 2-6 hours under the condition of heat preservation to obtain the graphite material modified by the tin oxide quantum dots.
The tin oxide quantum dot modified graphite material is prepared by respectively obtaining a first slurry and a second slurry through wet ball milling, mixing, adding graphite and aluminum tert-butoxide, adjusting the system viscosity through a water-based adhesive, spray drying to obtain a dry powder, and heating and calcining the dry powder by adopting a program. Specifically, cheap and easily-obtained natural substances such as glucose and graphite are used as carbon sources, and a silica matrix and stannous chloride are not easily adhered to a grinding ball in a wet ball milling process, so that slurry is more uniformly mixed and has good fluidity; after the tert-butyl alcohol aluminum is added, the reaction can be carried out with the byproduct silicon dioxide generated by the oxidation of the silicon monoxide, so that the silicon dioxide is converted into the silicate without consuming lithium ions, and the irreversible capacity loss generated by the silicon dioxide is reduced; under the balling action of spray drying, the silicon oxide particles and the tin oxide particles are tightly adhered to the surface of the graphite through a water-based adhesive to form a core-shell coating structure, so that the conductivity and the lithium ion transmission performance of the lithium battery are improved, and the cycle life of the lithium battery is prolonged.
Further, the mass ratio of the silica matrix to the absolute ethyl alcohol is 1: 3-5, wherein the mass ratio of the glucose to the stannous chloride to the water is 1: 1.2-1.6: 2.5 to 3.
Furthermore, the adding amount of the graphite and the aluminum tert-butoxide is 60-80% and 12-18% of the mass of the mixed slurry respectively.
Further, the temperature is increased to 250-300 ℃ at a rate of 10-15 ℃/min, and the temperature is increased to 900-1100 ℃ at a rate of 15-20 ℃/min.
Further, the preparation method of the water-based adhesive comprises the following steps: weighing pre-dehydrated polycaprolactone diol, hydroxyl-terminated polybutadiene acrylonitrile and isophorone isocyanate, adding the pre-dehydrated polycaprolactone diol, hydroxyl-terminated polybutadiene acrylonitrile and isophorone isocyanate into a three-neck flask provided with a condenser tube, a mechanical stirrer and a dropping funnel, dropwise adding tetrabutyl titanate serving as a catalyst, heating to 80-90 ℃, carrying out heat preservation stirring reaction for 1-2 hours, adding 1, 4-cyclohexanediol serving as a chain extender, continuing to carry out heat preservation reaction for 50-80 min, cooling to 55-65 ℃, adding triethylamine for neutralization reaction, adding ethylenediamine for chain extension, and emulsifying and dispersing with deionized water for 30-40 min to obtain the hydroxyl-terminated polybutadiene acrylonitrile modified polyurethane aqueous adhesive.
Wherein, the grafting principle of hydroxyl-terminated polybutadiene acrylonitrile and isophorone isocyanate is as follows:
Figure 100002_DEST_PATH_IMAGE001
the preparation method of the aqueous adhesive comprises the steps of introducing acrylonitrile group into hydroxyl-terminated polybutadiene, wherein the hydroxyl-terminated polybutadiene acrylonitrile has the general characteristics of the hydroxyl-terminated polybutadiene, and also has good oil resistance, adhesion, aging resistance and low temperature resistance, and simultaneously, due to the introduction of the acrylonitrile group, the polarity is improved, so that the hydroxyl-terminated polybutadiene acrylonitrile modified polyurethane aqueous adhesive is obtained under the catalysis of tetrabutyl titanate serving as a catalyst and the chain extension effect of 1, 4-cyclohexanediol serving as a chain extender. Because the hydroxyl-terminated polybutadiene acrylonitrile and the 1, 4-cyclohexanediol both have terminal hydroxyl groups and react with isocyanate to synthesize the waterborne polyurethane with a cross-linked network structure, the existence of various hydroxyl groups enhances the hydrogen bond effect of the waterborne adhesive and improves the thermal stability and the aging resistance. According to the water-based adhesive, the silicon oxide particles and the tin oxide particles are tightly adhered to the surface of graphite, and strong hydrogen bonds are formed between hydrogen bonds and amido bonds in the cross-linked network structure and the surfaces of the silicon particles and the graphite particles, so that the water-based adhesive can bear mechanical stress caused by the volume change of silicon, effectively inhibit volume expansion and keep the integrity of an electrode structure.
Further, the mass ratio of the polycaprolactone diol to the hydroxyl-terminated polybutadiene acrylonitrile to the isophorone isocyanate is 0.6-1.2: 2-3: 1.1-1.6, wherein the addition amounts of the catalyst tetrabutyl titanate and the chain extender 1, 4-cyclohexanediol are respectively 0.1-0.3% and 5-10% of the mass of the hydroxyl-terminated polybutadiene acrylonitrile.
The invention has the following beneficial effects:
1. according to the invention, the positive electrode is made of a high-capacity manganese-rich lithium-nickel-cobalt-manganese ternary composite material, the negative electrode is made of a graphite material modified by tin oxide quantum dots, so that the positive electrode and the negative electrode have high specific capacity density and conductivity, the lithium supplement additive is added in the positive electrode and the negative electrode, the first coulombic efficiency of the lithium battery is improved, and the conductivity is improved by adding the conductive agent, so that the rate capability of the battery is better; the lithium ion battery has good safety, rate capability, cycle life and energy density.
2. The graphite material modified by the tin oxide quantum dots adopts cheap and easily-obtained natural substances of glucose and graphite as carbon sources, and a silica matrix and stannous chloride are not easily adhered to a grinding ball in a wet ball milling process, so that slurry is more uniformly mixed and has good fluidity; the tert-butyl alcohol aluminum reacts with the byproduct silicon dioxide generated by the oxidation of the silicon monoxide, so that the silicon dioxide is converted into silicate without consuming lithium ions, and the irreversible capacity loss generated by the silicon dioxide is reduced; under the balling action of spray drying, the silicon oxide particles and the tin oxide particles are tightly adhered to the surface of the graphite through a water-based adhesive to form a core-shell coating structure, so that the conductivity, the lithium ion transmission performance and the cycle life of the lithium battery are improved.
3. In the aqueous adhesive, the existence of various hydroxyl groups enhances the hydrogen bond function of the aqueous adhesive, and improves the thermal stability and the aging resistance; the silicon oxide particles and the tin oxide particles are tightly adhered to the surface of graphite, and strong hydrogen bonds are formed between hydrogen bonds and amido bonds in the cross-linked network structure and the surfaces of the silicon particles and the graphite particles, so that the mechanical stress caused by the volume change of silicon is borne, the volume expansion is effectively inhibited, and the integrity of an electrode structure is kept.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
In the lithium-manganese-rich composite monocrystal ternary/silicon monoxide composite graphite lithium ion battery of the embodiment, the positive pole piece, the diaphragm, the negative pole piece and the diaphragm are sequentially placed from top to bottom during assembly, the diaphragm and the positive and negative pole pieces are assembled in a winding or laminating manner, a conductive agent and a lithium supplement additive are added to the positive and negative pole pieces, then an electrolyte is injected, a battery cell is obtained through encapsulation and aging, and the lithium ion battery pack is obtained through series connection or parallel connection of the battery cells.
The anode is made of a high-capacity manganese-lithium-rich and nickel-cobalt-manganese-rich ternary composite material, the cathode is made of a graphite material modified by tin oxide quantum dots, the diaphragm is made of an alumina ceramic diaphragm, the conductive agent is a mixture of a carbon nano tube and acetylene black according to the mass ratio of 1:1, and the electrolyte is high-pressure electrolyte; the lithium supplement additive is Li 0.79 Ni 1.21 O 2 With Li 2 O-Li 2/3 Mn 1/3 O 5/6 A mixture of (a).
The preparation method of the tin oxide quantum dot modified graphite material comprises the following steps:
uniformly mixing 100g of silica matrix and 460g of absolute ethyl alcohol, and performing wet ball milling to obtain first slurry with the particle size of 0.5-2 microns; mixing 100g of glucose, 145g of stannous chloride and 268g of water, and performing wet ball milling to obtain a second slurry with the particle size of 0.1-1.6 microns.
Mixing the first slurry and the second slurry according to a mass ratio of 1: 1.8, uniformly mixing to obtain mixed slurry, adding graphite accounting for 65% of the mass of the mixed slurry and 14% of aluminum tert-butoxide into the mixed slurry, uniformly stirring, and adding a water-based adhesive to adjust the viscosity of a mixed system to 600-800 mPa.S to obtain the mixed material.
Introducing the mixed material into a spray dryer for spray drying, and keeping the air inlet temperature at 145 ℃ and the air outlet temperature at 76 ℃ to obtain dry powder;
feeding the dried powder into a tube furnace, heating to 280 ℃ at the speed of 12 ℃/min under the protection of inert gas, and keeping the temperature for 25 min; heating to 1035 ℃ at the speed of 18 ℃/min, and carrying out heat preservation and calcination for 4.5 hours to obtain the graphite material modified by the tin oxide quantum dots.
The preparation method of the water-based adhesive comprises the following steps:
weighing 100g of polycaprolactone diol subjected to dehydration treatment in advance, 230g of hydroxyl-terminated polybutadiene acrylonitrile and 135g of isophorone isocyanate, adding the weighed materials into a three-neck flask provided with a condenser tube, a mechanical stirrer and a dropping funnel, dropwise adding 0.51g of tetrabutyl titanate serving as a catalyst, heating to 86 ℃, carrying out heat preservation stirring reaction for 1.6 hours, adding 18.4g of 1, 4-cyclohexanediol serving as a chain extender, continuing to carry out heat preservation reaction for 75 minutes, cooling to 62 ℃, adding triethylamine for neutralization reaction, adding 3.6g of ethylenediamine for chain extension, and carrying out emulsification and dispersion by using deionized water for 36 minutes to obtain the hydroxyl-terminated polybutadiene acrylonitrile modified polyurethane aqueous adhesive.
Example 2
In the lithium-manganese-rich composite monocrystal ternary/silicon monoxide composite graphite lithium ion battery of the embodiment, the positive pole piece, the diaphragm, the negative pole piece and the diaphragm are sequentially placed from top to bottom during assembly, the diaphragm and the positive and negative pole pieces are assembled in a winding or laminating manner, a conductive agent and a lithium supplement additive are added to the positive and negative pole pieces, then an electrolyte is injected, a battery cell is obtained through encapsulation and aging, and the lithium ion battery pack is obtained through series connection or parallel connection of the battery cells.
The anode is made of a high-capacity manganese-lithium-rich and nickel-cobalt-manganese-rich ternary composite material, the cathode is made of a graphite material modified by tin oxide quantum dots, the diaphragm is made of a boehmite ceramic diaphragm, the conductive agent is a mixture of carbon nanotubes and acetylene black according to the mass ratio of 1:1.5, and the electrolyte is high-pressure electrolyte; the lithium supplement additive is 3, 4-dihydroxy benzonitrile lithium and Li 2 O-Li 2/ 3 Mn 1/3 O 5/6 A mixture of (a).
The preparation method of the tin oxide quantum dot modified graphite material comprises the following steps:
uniformly mixing 100g of a silica matrix and 380g of absolute ethyl alcohol, and performing wet ball milling to obtain first slurry with the particle size of 0.5-2 microns; mixing 100g of glucose, 150g of stannous chloride and 280g of water, and performing wet ball milling to obtain a second slurry with the particle size of 0.1-1.6 microns.
Mixing the first slurry and the second slurry according to a mass ratio of 1: 1.9, uniformly mixing to obtain mixed slurry, adding 72% of graphite and 15% of aluminum tert-butoxide by mass of the mixed slurry into the mixed slurry, uniformly stirring, and adding a water-based adhesive to adjust the viscosity of a mixed system to 600-800 mPa.S, thereby obtaining the mixed material.
Introducing the mixed material into a spray dryer for spray drying, and keeping the air inlet temperature at 138 ℃ and the air exhaust temperature at 75 ℃ to obtain dry powder;
feeding the dried powder into a tube furnace, heating to 286 ℃ at a speed of 14 ℃/min under the protection of inert gas, and keeping the temperature for 25 min; heating to 985 ℃ at the speed of 18 ℃/min, and carrying out heat preservation and calcination for 5.5 hours to obtain the graphite material modified by the tin oxide quantum dots.
The preparation method of the water-based adhesive comprises the following steps:
weighing 85g of polycaprolactone diol, 250g of hydroxyl-terminated polybutadiene acrylonitrile and 135g of isophorone isocyanate which are subjected to dehydration treatment in advance, adding the polycaprolactone diol, 250g of hydroxyl-terminated polybutadiene acrylonitrile and 135g of isophorone isocyanate into a three-neck flask provided with a condenser tube, a mechanical stirrer and a dropping funnel, dropwise adding 0.48g of tetrabutyl titanate catalyst, heating to 88 ℃, keeping the temperature, stirring and reacting for 1.8 hours, adding 17.5g of chain extender 1, 4-cyclohexanediol, continuing to keep the temperature, reacting for 72 minutes, cooling to 63 ℃, adding triethylamine for neutralization reaction, adding 4.2g of ethylenediamine for chain extension, and emulsifying and dispersing by deionized water for 35 minutes to obtain the hydroxyl-terminated polybutadiene acrylonitrile modified polyurethane water-based adhesive.
Example 3
In the lithium-rich manganese-based composite single-crystal ternary/silicon monoxide composite graphite lithium ion battery of the embodiment, the positive pole piece, the diaphragm, the negative pole piece and the diaphragm are sequentially placed from top to bottom during assembly, the diaphragm and the positive and negative pole pieces are assembled in a winding or lamination mode, a conductive agent and a lithium supplement additive are added to the positive and negative pole pieces, then an electrolyte is injected, a battery cell is obtained through encapsulation and aging, and the battery cell is connected in series or in parallel to obtain the lithium ion battery pack.
The anode is made of a high-capacity manganese-lithium-rich and nickel-cobalt-manganese-rich ternary composite material, the cathode is made of a graphite material modified by tin oxide quantum dots, the diaphragm is made of a boehmite ceramic diaphragm, the conductive agent is a mixture of carbon nanotubes and acetylene black according to the mass ratio of 1.2:1, and the electrolyte is high-pressure electrolyte; the lithium supplement additive is Li 0.79 Ni 1.21 O 2 And a mixture of lithium silicide.
The preparation method of the tin oxide quantum dot modified graphite material comprises the following steps:
uniformly mixing 100g of silica matrix and 460g of absolute ethyl alcohol, and performing wet ball milling to obtain first slurry with the particle size of 0.5-2 microns; and mixing 100g of glucose, 152g of stannous chloride and 285g of water, and performing wet ball milling to obtain a second slurry with the particle size of 0.1-1.6 microns.
Mixing the first slurry and the second slurry according to a mass ratio of 1: 1.6, uniformly mixing to obtain mixed slurry, adding 75% of graphite and 13% of aluminum tert-butoxide by mass of the mixed slurry into the mixed slurry, uniformly stirring, and adding a water-based adhesive to adjust the viscosity of a mixed system to 600-800 mPa.S, thereby obtaining the mixed material.
Introducing the mixed material into a spray dryer for spray drying, and keeping the air inlet temperature at 147 ℃ and the air exhaust temperature at 78 ℃ to obtain dry powder;
feeding the dried powder into a tube furnace, heating to 290 ℃ at a speed of 15 ℃/min under the protection of inert gas, and keeping the temperature for 30 min; heating to 1085 ℃ at the speed of 19 ℃/min, and carrying out heat preservation and calcination for 6 hours to obtain the graphite material modified by the tin oxide quantum dots.
The preparation method of the water-based adhesive comprises the following steps:
112g of polycaprolactone diol, 287g of hydroxyl-terminated polybutadiene acrylonitrile and 136g of isophorone isocyanate which are subjected to dehydration treatment in advance are weighed, added into a three-neck flask provided with a condenser, a mechanical stirrer and a dropping funnel, 0.75g of tetrabutyl titanate serving as a catalyst is dropwise added, the temperature is raised to 90 ℃, the mixture is subjected to heat preservation stirring reaction for 1.8 hours, 25.6g of 1, 4-cyclohexanediol serving as a chain extender is added, the heat preservation reaction is continued for 75 minutes, the temperature is lowered to 63 ℃, triethylamine is added for neutralization reaction, 3.8g of ethylenediamine is added for chain extension, and after deionized water is emulsified and dispersed for 40 minutes, the hydroxyl-terminated polybutadiene acrylonitrile modified polyurethane water-based adhesive is obtained.
Example 4
In the lithium-manganese-rich composite monocrystal ternary/silicon monoxide composite graphite lithium ion battery of the embodiment, the positive pole piece, the diaphragm, the negative pole piece and the diaphragm are sequentially placed from top to bottom during assembly, the diaphragm and the positive and negative pole pieces are assembled in a winding or laminating manner, a conductive agent and a lithium supplement additive are added to the positive and negative pole pieces, then an electrolyte is injected, a battery cell is obtained through encapsulation and aging, and the lithium ion battery pack is obtained through series connection or parallel connection of the battery cells.
The anode is made of a high-capacity manganese-lithium-rich and nickel-cobalt-manganese-rich ternary composite material, the cathode is made of a graphite material modified by tin oxide quantum dots, the diaphragm is made of an alumina ceramic diaphragm, the conductive agent is a mixture of a carbon nano tube and acetylene black according to the mass ratio of 1:1.5, and the electrolyte is high-pressure electrolyte; the lithium supplement additive is Li 2 O-Li 2/3 Mn 1/3 O 5/6 And a mixture of lithium silicide.
The preparation method of the tin oxide quantum dot modified graphite material comprises the following steps:
uniformly mixing 100g of a silica matrix and 360g of absolute ethyl alcohol, and performing wet ball milling to obtain first slurry with the particle size of 0.5-2 microns; mixing 100g of glucose, 152g of stannous chloride and 286g of water, and performing wet ball milling to obtain a second slurry with the diameter of 0.1-1.6 microns.
Mixing the first slurry and the second slurry according to a mass ratio of 1: 1.9, uniformly mixing to obtain mixed slurry, adding 76% of graphite and 16% of aluminum tert-butoxide by mass of the mixed slurry into the mixed slurry, uniformly stirring, and adding a water-based adhesive to adjust the viscosity of a mixed system to 600-800 mPa.S, thereby obtaining the mixed material.
Introducing the mixed material into a spray dryer for spray drying, and keeping the air inlet temperature at 150 ℃ and the air exhaust temperature at 80 ℃ to obtain dry powder;
feeding the dried powder into a tube furnace, heating to 295 ℃ at a speed of 14 ℃/min under the protection of inert gas, and keeping the temperature for 24 min; heating to 1030 ℃ at the speed of 20 ℃/min, and carrying out heat preservation and calcination for 4.5 hours to obtain the graphite material modified by the tin oxide quantum dots.
The preparation method of the water-based adhesive comprises the following steps:
weighing 96g of polycaprolactone diol, 240g of hydroxyl-terminated polybutadiene acrylonitrile and 152g of isophorone isocyanate which are subjected to dehydration treatment in advance, adding the weighed materials into a three-neck flask provided with a condenser tube, a mechanical stirrer and a dropping funnel, dropwise adding 0.6g of tetrabutyl titanate catalyst, heating to 87 ℃, carrying out heat preservation stirring reaction for 2 hours, adding 22g of chain extender 1, 4-cyclohexanediol, continuing to carry out heat preservation reaction for 75 minutes, cooling to 63 ℃, adding triethylamine for neutralization reaction, adding 4.5g of ethylenediamine for chain extension, and emulsifying and dispersing with deionized water for 35 minutes to obtain the hydroxyl-terminated polybutadiene acrylonitrile modified polyurethane aqueous adhesive.
Comparative example 1
The comparative example differs from example 1 in that the aqueous adhesive was replaced with a commercially available aqueous polyurethane during the preparation of the tin oxide quantum dot modified graphite material.
Comparative example 2
The comparative example differs from example 1 in that the tin oxide quantum dot modified graphite material was replaced with a natural graphite material.
Comparative example 3
The difference between the comparative example and the example 1 is that no lithium supplement additive is added in the positive and negative electrode plates.
Measurement of Charge and discharge Properties
The lithium batteries prepared in examples 1-4 and comparative examples 1-3 were tested for the first discharge specific capacity, the first charge-discharge efficiency and the 50-cycle capacity retention rate by performing charge-discharge at a current density of 0.2C with a charge-discharge voltage limit of 0.01-2V, and the specific test results are shown in the following table:
test item Specific capacity of first discharge (mAh/g) Specific capacity for first charge (mAh/g) First charge-discharge efficiency (%) Retention ratio of 50-week cycle capacity (%)
Example 1 965 883 91.5 88.4
Example 2 948 865 91.2 88.2
Example 3 957 865 90.4 87.4
Example 4 952 864 90.8 86.7
Comparative example 1 827 648 78.4 64.5
Comparative example 2 751 547 72.8 60.8
Comparative example 3 885 756 85.4 72.4
The lithium ion battery prepared by the embodiment of the invention is superior to the comparative example in the first discharge specific capacity, the first charge-discharge efficiency and the 50-week cycle capacity retention rate, the first charge-discharge efficiency reaches 90.4-91.5%, and the comparative example replaces a water-based adhesive, a tin oxide quantum dot modified graphite material and no lithium supplement additive, so that the electrochemical performance is remarkably reduced, the first irreversible capacity loss is large, and the cycle performance is poor.
The foregoing is merely exemplary and illustrative of the present invention and various modifications, additions and substitutions may be made by those skilled in the art to the specific embodiments described without departing from the scope of the invention as defined in the following claims.
In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best understand the invention for and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims (6)

1. The lithium-rich manganese-based composite single crystal ternary/silicon monoxide composite graphite lithium ion battery is characterized in that a positive pole piece, a diaphragm, a negative pole piece and the diaphragm are sequentially placed from top to bottom during assembly, the diaphragm and the positive and negative pole pieces are assembled in a winding or laminating mode, a conductive agent and a lithium supplement additive are added into the positive and negative pole pieces, then an electrolyte is injected into the positive and negative pole pieces, an electric core is obtained through packaging and aging, and the lithium ion battery pack is obtained through series connection or parallel connection of the electric core;
wherein, the anode adopts a high-capacity manganese-rich lithium and nickel-cobalt-manganese ternary composite material, and the cathode adopts a tin oxide quantum dot modified graphite materialThe material, the diaphragm adopts alumina or boehmite ceramic diaphragm, the conductive agent adopts the mixture of carbon nanotube and acetylene black, the electrolyte adopts high-pressure electrolyte; the lithium supplement additive is Li 0.79 Ni 1.21 O 2 Lithium, Li 3, 4-dihydroxybenzonitrile 2 O-Li 2/3 Mn 1/ 3 O 5/6 And lithium silicide or a mixture of both;
the preparation method of the tin oxide quantum dot modified graphite material comprises the following steps:
uniformly mixing a silica substrate and absolute ethyl alcohol, and carrying out wet ball milling to obtain first slurry with the particle size of 0.5-2 mu m; mixing glucose, stannous chloride and water, and performing wet ball milling to obtain a second slurry with a solid content of 20-30% and a particle size of 0.1-1.6 microns;
mixing the first slurry and the second slurry according to a mass ratio of 1: 1.5-2, uniformly mixing to obtain mixed slurry, adding graphite and aluminum tert-butoxide into the mixed slurry, uniformly stirring, and adding a water-based adhesive to adjust the viscosity of the mixed system to 600-800 mPa & S to obtain a mixed material;
introducing the mixed material into a spray dryer for spray drying, and keeping the air inlet temperature at 130-150 ℃ and the air exhaust temperature at 70-80 ℃ to obtain dried powder;
feeding the dried powder into a tube furnace, heating to 250-300 ℃ under the protection of inert gas, and preserving heat for 20-30 min; heating to 900-1100 ℃, and calcining for 2-6 hours under heat preservation to obtain the graphite material modified by the tin oxide quantum dots;
the aqueous adhesive is a hydroxyl-terminated polybutadiene acrylonitrile modified polyurethane aqueous adhesive, which is formed by grafting hydroxyl-terminated polybutadiene acrylonitrile and isophorone isocyanate, and the grafting reaction principle is as follows:
Figure DEST_PATH_IMAGE001
。
2. the lithium-rich manganese-based composite single-crystal ternary/silica composite graphite lithium ion battery according to claim 1, wherein the mass ratio of the silica matrix to the absolute ethyl alcohol is 1: 3-5, wherein the mass ratio of the glucose to the stannous chloride to the water is 1: 1.2-1.6: 2.5 to 3.
3. The lithium-rich manganese-based composite single-crystal ternary/silicon monoxide composite graphite lithium ion battery as claimed in claim 1, wherein the addition amounts of the graphite and the aluminum tert-butoxide are respectively 60-80% and 12-18% of the mass of the mixed slurry.
4. The lithium-rich manganese-based composite single crystal ternary/silicon monoxide composite graphite lithium ion battery according to claim 1, wherein the temperature is raised to 250-300 ℃ at a rate of 10-15 ℃/min, and is raised to 900-1100 ℃ at a rate of 15-20 ℃/min.
5. The lithium-rich manganese-based composite single crystal ternary/silicon monoxide composite graphite lithium ion battery according to claim 1, wherein the preparation method of the aqueous adhesive comprises the following steps: weighing polycaprolactone diol, hydroxyl-terminated polybutadiene acrylonitrile and isophorone isocyanate subjected to dehydration treatment in advance, adding the weighed materials into a three-neck flask provided with a condenser pipe, a mechanical stirrer and a dropping funnel, dropwise adding tetrabutyl titanate serving as a catalyst, heating to 80-90 ℃, carrying out heat preservation stirring reaction for 1-2 hours, adding 1, 4-cyclohexanediol serving as a chain extender, continuing to carry out heat preservation reaction for 50-80 minutes, cooling to 55-65 ℃, adding triethylamine for neutralization reaction, adding ethylenediamine for chain extension, and carrying out emulsification and dispersion on deionized water for 30-40 minutes to obtain the hydroxyl-terminated polybutadiene acrylonitrile modified polyurethane water-based adhesive.
6. The lithium-rich manganese-based composite single crystal ternary/silicon oxide composite graphite lithium ion battery of claim 5, wherein the mass ratio of polycaprolactone diol to hydroxyl-terminated polybutadiene acrylonitrile to isophorone isocyanate is 0.6-1.2: 2-3: 1.1-1.6, wherein the addition amounts of the catalyst tetrabutyl titanate and the chain extender 1, 4-cyclohexanediol are respectively 0.1-0.3% and 5-10% of the mass of the hydroxyl-terminated polybutadiene acrylonitrile.
CN202210269445.4A 2022-03-18 2022-03-18 Lithium-rich manganese-based composite single crystal ternary/silicon oxide composite graphite lithium ion battery Active CN114597391B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210269445.4A CN114597391B (en) 2022-03-18 2022-03-18 Lithium-rich manganese-based composite single crystal ternary/silicon oxide composite graphite lithium ion battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210269445.4A CN114597391B (en) 2022-03-18 2022-03-18 Lithium-rich manganese-based composite single crystal ternary/silicon oxide composite graphite lithium ion battery

Publications (2)

Publication Number Publication Date
CN114597391A CN114597391A (en) 2022-06-07
CN114597391B true CN114597391B (en) 2022-09-27

Family

ID=81810949

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210269445.4A Active CN114597391B (en) 2022-03-18 2022-03-18 Lithium-rich manganese-based composite single crystal ternary/silicon oxide composite graphite lithium ion battery

Country Status (1)

Country Link
CN (1) CN114597391B (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104577188A (en) * 2014-12-23 2015-04-29 山东神工海特电子科技有限公司 Ternary hybrid lithium manganate lithium-ion power battery and manufacturing method thereof
CN107978800A (en) * 2018-01-15 2018-05-01 华动智慧信息技术（深圳）有限公司 Single battery is realized the method and preparation and its battery pack preparation method of high pressure
CN110137467A (en) * 2019-05-14 2019-08-16 珠海冠宇电池有限公司 A kind of lithium ion battery of high-energy density
CN211907608U (en) * 2020-05-07 2020-11-10 浙江浙能技术研究院有限公司 Lithium ion battery structure

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104577188A (en) * 2014-12-23 2015-04-29 山东神工海特电子科技有限公司 Ternary hybrid lithium manganate lithium-ion power battery and manufacturing method thereof
CN107978800A (en) * 2018-01-15 2018-05-01 华动智慧信息技术（深圳）有限公司 Single battery is realized the method and preparation and its battery pack preparation method of high pressure
CN110137467A (en) * 2019-05-14 2019-08-16 珠海冠宇电池有限公司 A kind of lithium ion battery of high-energy density
CN211907608U (en) * 2020-05-07 2020-11-10 浙江浙能技术研究院有限公司 Lithium ion battery structure

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
"Synthesis of the microspherical structure of ternary SiOx@SnO2@C by a hydrothermal method as the anode for high-performance lithium-ion batteries";Zhiqiang Gu等;《Sustainable Energy & Fuels》;20200217;第4卷;第2333～2341页 *

Also Published As

Publication number Publication date
CN114597391A (en) 2022-06-07

Similar Documents

Publication Publication Date Title
CN105810899A (en) Lithium ion battery
CN103620836A (en) Nonaqueous electrolyte secondary cell and method for manufacturing same
CN102569773B (en) Anode material for lithium-ion secondary battery and preparation method thereof
CN104617272A (en) Method for preparing porous silicon-carbon composite material
CN107146875A (en) A kind of heat chemistry blocking-up type composite positive pole, anode pole piece and preparation method thereof, lithium ion battery
CN109686920A (en) A kind of high-energy density anode pole piece and its preparation method and application
CN114094068B (en) Cobalt-coated positive electrode material, preparation method thereof, positive electrode plate and lithium ion battery
CN103000874A (en) Preparation method of carbon-coated ternary positive electrode material
CN104425822B (en) A kind of graphite negative material of lithium ion battery and preparation method thereof
CN115714170B (en) Preparation method of high-energy-density quick-charge anode material
CN105591099A (en) Lithium molybdate surface modified lithium ion battery nickel-rich positive pole material and preparation method thereof
WO2022151648A1 (en) High-capacity highly stable silicon-carbon negative electrode material and preparation method therefor
CN107946564B (en) Rich in Na4Mn2O5/Na0.7MnO2Composite material and preparation method and application thereof
CN114628684B (en) High-energy-density quick-charging graphite composite material and preparation method thereof
CN113889594A (en) Preparation method of boron-doped lithium lanthanum zirconate-coated graphite composite material
CN103531789A (en) Iron oxide-carbon nanotube ternary composite material and preparation method thereof
CN114620702A (en) Preparation method of positive electrode material, positive plate and sodium ion battery
CN117219777B (en) Lithium supplementing agent, preparation method thereof, positive electrode plate and secondary battery
CN111613791B (en) Negative electrode active material, silicon-carbon negative electrode piece and high-energy-density quick-charging lithium ion battery
CN105958027A (en) Manganese-based composite positive electrode material and preparation method therefor
CN107946586A (en) NCM iron phosphate compound anode material of lithium, lithium ion battery and preparation method thereof
CN114597391B (en) Lithium-rich manganese-based composite single crystal ternary/silicon oxide composite graphite lithium ion battery
CN116682951A (en) Positive electrode active material, positive electrode sheet, preparation method of positive electrode sheet and lithium ion battery
CN103367728A (en) Activated natural graphite modified Li2FeSiO4 cathode material and its preparation method
CN111799467B (en) MoS for negative electrode of sodium-ion battery 2 /MoS 2 Nanocomposite and method for preparing same

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