CN114551818B - Nano silicon composite particles, negative plate and solid lithium battery - Google Patents
Nano silicon composite particles, negative plate and solid lithium battery Download PDFInfo
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- 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
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- 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
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- 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
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- H—ELECTRICITY
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- 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
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- H—ELECTRICITY
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- 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
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- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention relates to the technical field of battery materials, and discloses nano silicon composite particles, a negative plate and a solid lithium battery, wherein the nano silicon composite particles are N-P-COF-GO modified nano silicon composite particles, COF and GO are loaded on the surfaces of silicon nano particles, and N and P are co-doped in the COF and GO; dispersing silicon nano particles, a phosphorus source material, a nitrogen source material and graphene oxide in an organic solvent, and synthesizing N-P-COF-GO modified nano silicon composite particles by adopting a solvothermal method; the negative plate and the solid lithium battery are prepared by utilizing the nano silicon composite particles. The invention overcomes the defects of remarkable volume expansion and continuous growth of the surface SEI layer of the silicon material in continuous charge and discharge, realizes rapid transmission and storage of lithium ions, and the negative electrode plate and the solid lithium battery prepared by utilizing the nano silicon composite particles have lower alternating current impedance, higher discharge capacity and cycle performance.
Description
Technical Field
The invention relates to the technical field of battery materials, in particular to nano silicon composite particles, a negative plate and a solid lithium battery.
Background
Silicon (Si) has very high theoretical capacity (3579 mAh/g), is considered as one of the most promising solid lithium battery anode materials, and the solid lithium battery has high energy density and is the preferred choice for the development of next-generation lithium battery products. The energy density of the all-solid-state lithium battery using the silicon-based negative electrode is far higher than that of the existing liquid lithium ion secondary battery, the occurrence of lithium dendrite can be avoided, and the safety performance is good. However, significant volume expansion of silicon materials during sustained charge and discharge and sustained growth of the surface solid electrolyte membrane (SEI) consume free lithium ions, resulting in rapid degradation of battery performance.
The combination of COFs with lithium batteries has attracted considerable attention in recent years in chemical and material science due to their high porosity and adjustable physicochemical properties, which is due to the high mechanical strength of ordered porous frameworks, enabling rapid transport and storage of lithium ions without large volume changes. The Chinese patent publication No. CN112736245A discloses a lithium ion battery negative electrode material, a preparation method and application thereof, wherein the lithium ion battery negative electrode material is formed by uniformly forming a film on the surface of a current collector through a dispersion liquid containing a covalent organic framework material, and the lithium ion battery negative electrode is obtained by electrochemically depositing metallic lithium on the lithium ion battery negative electrode material. The method has the defects that the covalent metal framework layer is directly used as a battery anode material, and compared with a silicon-based anode material, the theoretical capacity is low, the energy density of the obtained lithium ion battery is low, and the comprehensive electrochemical performance of the lithium ion battery is poor.
Disclosure of Invention
The invention aims to provide nano silicon composite particles, a negative plate and a solid lithium battery, which overcome the defects of remarkable volume expansion and continuous growth of a surface SEI layer of a silicon material in continuous charge and discharge on the premise of keeping the advantages of high theoretical capacity and energy density of the silicon-based negative electrode material, and realize rapid transmission and storage of lithium ions.
The aim of the invention is achieved by the following technical scheme.
The invention provides nano silicon composite particles used as a lithium battery anode material, wherein the nano silicon composite particles are N-P-COF-GO modified nano silicon composite particles, COF and GO are loaded on the surfaces of silicon nano particles, and N and P are co-doped in the COF and GO.
The Covalent Organic Framework (COF) is a stable and ordered porous framework structure, and after being compounded with the nano silicon particles, the Covalent Organic Framework (COF) relieves and inhibits the severe volume change of the nano silicon particles, reduces the generation of a surface SEI film, and meanwhile, a large number of redox active centers and long-range ordered open channels exist in the COF, so that the diffusion path of lithium ions is more convenient, and the electrochemical performance of the battery is more excellent.
Meanwhile, graphene Oxide (GO) has excellent lithium ion transmission performance, and the addition of graphene oxide can also increase the conductivity of silicon particles. COF possesses high mechanical strength because of its orderly porous skeleton, and GO mechanical strength is lower, and the compound of COF and GO has formed the lithium ion transmission passageway of just gentle combination, can realize lithium ion's quick transmission and storage under the circumstances that does not have big volume variation. The addition of COF and GO can also buffer particle pulverization and SEI film continuous growth caused by the volume expansion of silicon particles, prolong the service life and improve the structure and chemical stability of the material.
Doping of the nitrogen source material (N) and the phosphorus source material (P) endows the COF and the GO with more topological defects and larger interlayer spacing, and further enhances the transmission performance of electrons and ions. Therefore, the solid lithium battery corresponding to the N-P-COF-GO modified nano silicon particles has lower alternating current impedance and higher discharge capacity and cycle performance.
Preferably, the preparation method of the nano-silicon composite particles comprises the following steps:
dispersing silicon nano particles, a phosphorus source material, a nitrogen source material and graphene oxide in an organic solvent, and performing ultrasonic treatment at normal temperature; adding the obtained mixed solution into a Pyrex tube, regulating the pH to 5-6, then carrying out ultrasonic mixing at normal temperature, quickly freezing in liquid nitrogen, and degassing through thawing circulation; heating the Pyrex tube, filtering, washing the precipitate, removing impurities on the surface, and then carrying out vacuum drying and sintering; and after cooling to room temperature, ball milling the obtained powder to obtain the nano silicon composite particles.
Preferably, the particle size of the silicon nanoparticle is 50-500 nm; the mass ratio of the silicon nano particles to the phosphorus source material to the nitrogen source material to the graphene oxide is (30-40): (0.001-0.003): (0.001-0.003): (0.5-2.0); the organic solvent comprises a solvent a and a solvent b, wherein the volume ratio of the solvent a to the solvent b is 2-3: 0.5 to 1; the ultrasonic duration at the normal temperature is 40-60 minutes; the solvent used for regulating the pH value to be 5-6 is one of acetic acid, citric acid, tartaric acid and malic acid; the ultrasonic mixing time is 20-40 minutes at normal temperature after the pH is regulated; the heating temperature in the Pyrex tube is 80-120 ℃ and the heating time is 24-60 hours; the filtered washing solvent is deionized water and ethanol; the vacuum drying temperature is 60 ℃, the vacuum drying time is 4-6 hours, the vacuum sintering temperature is 300-400 ℃, and the vacuum sintering time is 8-12 hours; the ball milling time is 10-30 minutes.
Preferably, the phosphorus source material is one or more phosphate esters; the nitrogen source material is one of acrylamide, polyacrylamide, N-p-hydroxyphenyl acrylamide, isopropyl acrylamide and N- (3-aminopropyl) methacrylamide; the solvent a is one of dioxane and dimethylformamide, preferably dioxane; the solvent b is one of trimethylbenzene, toluene, xylene, tetramethylbenzene and pentamethylene, and preferably trimethylbenzene.
Preferably, the phosphorus source material is phosphoenone pyruvic acid, and the nitrogen source material is acrylamide.
Acrylamide reacts for a long time (heated for 24-60 hours in the range of 80-120 ℃) in a high temperature Pyrex tube to form COF microcrystalline aggregates, and the acrylamide can form COF or can be used as a nitrogen source to be doped in COF and GO. Acrylamide is used as a nitrogen source, phosphoenolpyruvate is used as a phosphorus source, and a COF porous structure and a GO lamellar structure are doped in the vacuum sintering process at 300-400 ℃ to form a structure in which N and P are co-doped in COF and GO.
The invention also provides a negative plate which comprises the nano silicon composite particles.
Preferably, the negative electrode plate is a double-layer silicon-based composite negative electrode plate, and the preparation method comprises the following steps of ball milling a mixture of nano silicon composite particles and LATP, and pressing the mixed powder into a film to obtain a silicon-based film; stirring polymer electrolyte and chlorate electrolyte in an organic solvent until the polymer electrolyte and chlorate electrolyte are fully dissolved, and uniformly coating the obtained mixed solution on one side of a silicon-based film layer to form a polymer solid electrolyte layer; and (5) after vacuum drying, finally preparing the double-layer silicon-based composite negative plate.
Compared with a single-layer silicon-based composite negative electrode plate, the double-layer silicon-based composite negative electrode plate has the advantages that the silicon-based film layer is prevented from being directly contacted with the electrode, and is not easy to fall off from the electrode in the charging and discharging process, and the service life is prolonged. And the energy density and the cycle life of the solid lithium battery can be obviously improved, and the preparation method is a more stable preparation method of the silicon-based composite negative plate.
Preferably, the mass ratio of the nano silicon composite particles to the LATP is 8-10: 1.0 to 2.0; the ball milling time is 10-20 minutes; the pressing condition is that pressing is carried out under 50-200 standard atmospheric pressures; the thickness of the silicon-based film layer is 50-150 mu m; the molar ratio of the polymer electrolyte to the chlorate electrolyte is 7-10: 1 to 3; the temperature of the polymer electrolyte and the chlorate electrolyte is 45-55 ℃ when the polymer electrolyte and the chlorate electrolyte are dissolved in an organic solvent, the stirring time is 3-5 hours, and the organic solvent is one of acetonitrile, methanol, tetrahydrofuran, N-dimethylformamide, dimethyl sulfoxide, diethyl ether and carbon tetrachloride; the thickness of the polymer solid electrolyte layer is 10-15 mu m; the temperature of the vacuum drying is 30-40 ℃ and the time is 12-20 hours.
Preferably, the polymer electrolyte is one of polyethylene oxide, polymethacrylic acid, polyurethane, polyvinylidene fluoride, polyacrylonitrile and polymethyl methacrylate, preferably polyethylene oxide; the chlorate electrolyte is one of cesium perchlorate, lithium perchlorate, sodium perchlorate, potassium perchlorate and rubidium perchlorate, preferably cesium perchlorate.
Polyethylene oxide (PEO) is a flexible semi-crystalline polymer, has high lithium ion transmission capacity in an amorphous region and good interface compatibility, and can solve the problem of interface incompatibility between LATP solid electrolyte and solid silicon-based particles. Cesium perchlorate forms a salt bridge on the surface of LATP, repairs surface grain boundaries, and reduces interface resistance. The polymer solid electrolyte layer composed of PEO and cesium perchlorate is used as a buffer layer between LATP and a silicon-based negative electrode, so that the interfacial compatibility between LATP solid particles and nano silicon composite particles is improved, the deposition of lithium ions on the negative electrode sheet is more uniform, and the electrochemical performance of the battery is improved.
The invention also provides a solid lithium battery, which comprises the negative plate.
Compared with the prior art, the invention has the following beneficial effects:
(1) On the premise of keeping the advantages of high theoretical capacity and energy density of the silicon-based anode material, the nano silicon composite particles overcome the defects of remarkable volume expansion and continuous growth of a surface SEI layer of the silicon material in continuous charge and discharge, and realize rapid transmission and storage of lithium ions;
(2) The double-layer silicon-based composite negative plate avoids the direct contact of a silicon-based film layer with an electrode, is not easy to fall off from the electrode in the charge-discharge process, prolongs the service life, improves the deposition uniformity of lithium ions on the negative plate, and finally ensures the performance to be more stable;
(3) The negative plate and the solid lithium battery prepared by the nano silicon composite particles have lower alternating current impedance, higher discharge capacity and cycle performance, and better comprehensive electrochemical performance.
Detailed Description
The technical scheme of the present invention is described below by using specific examples, but the scope of the present invention is not limited thereto:
example 1
1. Preparation of nano silicon composite particles
The nano silicon composite particle is N-P-COF-GO modified nano silicon composite particle, and is a structure in which COF and GO are alternately loaded on the surface of a silicon nano particle and N and P are co-doped in the COF and GO.
The preparation method of the nano silicon composite particles comprises the following steps:
dispersing silicon nanoparticles, phosphoenolpyruvic acid, acrylamide and graphene oxide in an organic solvent, wherein the particle size of the silicon nanoparticles is 50nm (the purity is more than 99%), and the mass ratio of the silicon nanoparticles to the phosphoenolpyruvic acid to the acrylamide to the graphene oxide is 33:0.002:0.002:1.5, the volume ratio of the dioxane to the trimethylbenzene is 3: 1.
And (3) carrying out ultrasonic treatment on the mixture at normal temperature for 60 minutes, adding the obtained mixed solution into a Pyrex tube, adjusting the pH to 5-6 by using acetic acid, wherein the concentration of the acetic acid is 5mol/L, and the molar ratio of the acetic acid to silicon is 20:3. Then, the mixture was sonicated at room temperature for 40 minutes, rapidly frozen in liquid nitrogen, and deaerated by a freeze pump thawing cycle. Heating the Pyrex tube at 90 ℃ for 45 hours, filtering, washing the precipitate with deionized water and ethanol, and removing impurities on the surface. Vacuum drying at 60 deg.c for 6 hr, and vacuum sintering at 300 deg.c for 12 hr. And after sintering, cooling to room temperature, putting the obtained powder into a high-energy vibration ball mill, and ball milling for 30 minutes at normal temperature to obtain the nano silicon composite particles.
2. Preparation of double-layer silicon-based composite negative plate
Adding the N-P-COF-GO modified nano silicon particles and LATP prepared in the step 1 into a ball mill according to the mass ratio of 8:1.0, ball milling for 10 minutes at normal temperature, transferring the mixed powder to a molybdenum alloy mold, and pressing to form a film under 100 standard atmospheric pressures to obtain a silicon-based film with the thickness of 100 mu m. Then the polymer electrolyte and the chlorate electrolyte are dissolved in acetonitrile at 45 ℃, the polymer electrolyte adopted is PEO, the chlorate electrolyte adopted is cesium perchlorate, and the mole ratio of PEO to cesium perchlorate is 8:1.5, stirring for 5 hours until fully dissolved. The mixed solution was uniformly coated on one side of the silicon-based film layer as a polymer solid electrolyte layer having a thickness of 13 μm. Vacuum drying is carried out for 19 hours at the temperature of 40 ℃ to finally prepare the double-layer silicon-based composite negative plate.
3. Solid lithium battery assembly and performance assessment
Mixing an anode active material, a LATP solid electrolyte and a conductive agent according to the ratio of 70:25:4, compressing the mixed material into particles under 200 standard atmospheric pressures, grinding for 25 minutes, repeating for 4 times to obtain a uniformly mixed composite anode material, compressing and combining the composite anode material with a 40 mu m thick indium foil under 200 standard atmospheric pressures to obtain a solid lithium battery anode plate, wherein the thickness of the anode plate is 100 mu m, and the anode material is lithium iron phosphate LFP. And (3) respectively pressing the double-layer silicon-based composite anode and the double-layer silicon-based composite anode prepared in the step (2) on two sides of the LATP solid electrolyte under 100 standard atmospheric pressures, wherein the coating layer sides of PEO and cesium perchlorate face one side of the LATP solid electrolyte, and preparing the button solid full battery.
And (3) carrying out constant-current constant-voltage charge and discharge circulation at the room temperature of the assembled solid battery within the range of 4.1V-2.5V and with the multiplying power of 0.4C. The internal resistance of the battery is measured by electrochemical alternating current impedance spectroscopy, the frequency range is 0.1HZ to 1MHZ, and the amplitude of the applied voltage is 5mV.
Example 2
Compared with the example 1, the particle diameter of the silicon nano particles in the preparation process of the nano silicon composite particles in the example 2 is 200nm, and the mass ratio of the silicon nano particles, the phosphoenone pyruvic acid, the acrylamide and the graphene oxide is 40:0.003:0.001:0.5; the volume ratio of dioxane to trimethylbenzene is 2:0.7; after ultrasonic mixing for 40 minutes at normal temperature, quick freezing in liquid nitrogen, degassing by freeze pump-thawing cycle, heating Pyrex tube at 120deg.C for 60 hours; vacuum drying at 60deg.C for 4 hr, and vacuum sintering at 400deg.C for 8 hr; the ball milling time was 10 minutes. The other conditions were the same as in example 1.
Example 3
Compared with example 1, the acrylamide in the preparation process of the nano silicon composite particles in example 3 is replaced by aliphatic n, n-methylene bisacrylamide, the particle size of the silicon nano particles is 500nm, and the mass ratio of the silicon nano particles, the ketene phosphate pyruvic acid, the n, n-methylene bisacrylamide and the graphene oxide is 30:0.001:0.003:2.0, the volume ratio of dioxane to trimethylbenzene is 2.5:0.5; after ultrasonic mixing for 20 minutes at normal temperature, quick freezing in liquid nitrogen, degassing by freeze pump-thawing cycle, heating Pyrex tube at 80 ℃ for 24 hours; vacuum drying at 60deg.C for 5 hr, and vacuum sintering at 350deg.C for 10 hr; the ball milling time was 20 minutes. The other conditions were the same as in example 1.
Example 4
In comparison with example 1, the ketene phosphate pyruvic acid used in example 4 was replaced by dialkyl phosphate, the positive electrode active material was lithium manganate LMO, and the other conditions were the same as in example 1.
Example 5
Compared with the example 1, the thickness of the silicon-based film layer in the example 5 is 150 mu m, the thickness of the PEO and cesium perchlorate coating layer is 15 mu m, and the double-layer silicon-based composite negative plate is dried for 20 hours at 30 ℃; the thickness of the positive electrode sheet was 200. Mu.m. The other conditions were the same as in example 1.
Example 6
Compared with the example 1, the thickness of the silicon-based film layer in the example 6 is 50 mu m, the thickness of the PEO and cesium perchlorate coating layer is 10 mu m, and the double-layer silicon-based composite negative plate is dried for 12 hours at 35 ℃; the positive electrode sheet had a thickness of 50. Mu.m. The other conditions were the same as in example 1.
Example 7
Compared with example 1, the mass ratio of the N-P-COF-GO modified nano silicon particles to the LATP in example 7 is 10.0:2.0; ball milling time is 20 minutes; pressing the silicon-based film layer under 200 atmospheres; the PEO to cesium perchlorate molar ratio is 7:1 in acetonitrile at 55 degrees celsius for 4 hours. The other conditions were the same as in example 1.
Example 8
Compared with example 1, the mass ratio of the N-P-COF-GO modified nano silicon particles to the LATP in example 8 is 9.0:1.5; ball milling time is 15 minutes; pressing the silicon-based film layer at 100 atmospheres; the PEO to cesium perchlorate molar ratio is 10:3, stirring in acetonitrile at 50 degrees celsius for 3 hours. The other conditions were the same as in example 1.
Comparative example 1
In comparison with example 1, the nano-silicon composite particles in comparative example 1 did not contain COF modification, and the other conditions were the same as in example 1.
Comparative example 2
In comparison with example 1, the nano-silicon composite particles in comparative example 2 did not contain GO modification, and the other conditions were the same as in example 1.
Comparative example 3
In comparison with example 1, the nano-silicon composite particles in comparative example 3 were not doped with N, P, and the other conditions were the same as in example 1.
Comparative example 4
In comparison with example 1, comparative example 4 uses pure nano-silicon particles, and the other conditions are the same as in example 1.
Comparative example 5
Compared with example 1, the composite silicon-based negative electrode sheet of comparative example 5 has a single-layer structure, does not contain PEO and cesium perchlorate coating layers, and has the same other conditions as in example 1.
Comparative example 6
In comparison with example 1, the coating layer of the composite silicon-based negative electrode sheet of comparative example 5 contained no cesium perchlorate, only PEO, and the other conditions were the same as in example 1.
TABLE 1 comparison of Performance of solid lithium batteries prepared under different conditions
The specific results are shown in Table 1, and in combination with examples 1-8, it can be seen that the solid-state battery performance is significantly improved within the technical requirements of the present invention, and the results of example 1 are the best. By combining the embodiment 1 and the comparative examples 1-4, the N-P-COF-GO modified nano silicon particle cathode prepared by the method reduces the internal resistance and the cycle life of a solid battery, and is mainly because graphene with excellent lithium ion transmission performance and COFs form a rigid-flexible combined rapid lithium ion transmission channel, so that the volume change of silicon particles in the charge and discharge process is effectively reduced, the structure and the chemical stability of the material are improved, more structural defects are endowed to the N and P doping, and the transmission performance of electrons and ions is further enhanced. By combining example 1 with comparative examples 5-6, it was found that the transfer rate of lithium ions at the interface between the LATP solid electrolyte layer and the silicon-based negative electrode was significantly improved after the polymer solid electrolyte layer was coated on the surface of the silicon-based negative electrode, thereby improving the electrochemical performance of the solid lithium battery.
The results show that the method provided by the invention can obviously improve the stability of the silicon-based negative electrode, prolong the service life of the solid lithium battery and provide technical reference for researching the high-performance solid lithium battery.
The foregoing description is only of the preferred embodiments of the present invention, and is not intended to limit the scope of the invention, but rather is intended to cover any equivalents of the structures disclosed herein or modifications in the equivalent processes, or any application of the structures disclosed herein, directly or indirectly, in other related arts.
Claims (9)
1. The nano silicon composite particles are N-P-COF-GO modified nano silicon composite particles, COF and GO are loaded on the surfaces of the silicon nano particles, and N and P are co-doped in the COF and GO;
the preparation method comprises the following steps:
dispersing silicon nano particles, a phosphorus source material, a nitrogen source material and graphene oxide in an organic solvent, and performing ultrasonic treatment at normal temperature; adding the obtained mixed solution into a Pyrex tube, adjusting the pH to 5-6, carrying out ultrasonic mixing again at normal temperature, then quickly freezing in liquid nitrogen, and degassing through thawing circulation; heating the Pyrex tube, filtering, washing the precipitate, removing impurities on the surface, and then carrying out vacuum drying and vacuum sintering; after cooling to room temperature, ball milling the obtained powder to obtain the nano silicon composite particles;
the phosphorus source material is one or more phosphate esters;
the nitrogen source material is one of acrylamide, polyacrylamide, N-p-hydroxyphenyl acrylamide, isopropyl acrylamide and N- (3-aminopropyl) methacrylamide.
2. A nano-silicon composite particle for use as a negative electrode material for a lithium battery according to claim 1, wherein,
the particle size of the silicon nano particles is 50-500 nm;
the mass ratio of the silicon nano particles to the phosphorus source material to the nitrogen source material to the graphene oxide is (30-40): (0.001-0.003): (0.001-0.003): (0.5-2.0);
the organic solvent comprises a solvent a and a solvent b, wherein the volume ratio of the solvent a to the solvent b is 2-3: 0.5 to 1;
the ultrasonic duration at the normal temperature is 40-60 minutes;
the solvent used for regulating the pH value to be 5-6 is one of acetic acid, citric acid, tartaric acid and malic acid;
the ultrasonic mixing time is 20-40 minutes at normal temperature after the pH adjustment;
the heating temperature in the Pyrex tube is 80-120 ℃ and the heating time is 24-60 hours;
the filtered washing solvent is deionized water and ethanol;
the vacuum drying temperature is 60 ℃, the vacuum drying time is 4-6 hours, the vacuum sintering temperature is 300-400 ℃, and the vacuum sintering time is 8-12 hours;
the ball milling time is 10-30 minutes.
3. A nano-silicon composite particle for use as a negative electrode material for a lithium battery according to claim 2, wherein,
the solvent a is one of dioxane and dimethylformamide, and the solvent b is one of trimethylbenzene, toluene, xylene, tetramethylbenzene and pentamethylene.
4. A nano-silicon composite particle for use as a negative electrode material of a lithium battery according to claim 3, wherein the phosphorus source material is ketene phosphate pyruvic acid and the nitrogen source material is acrylamide.
5. A negative electrode sheet comprising the nano-silicon composite particles according to any one of claims 1 to 4.
6. The negative electrode sheet according to claim 5, wherein the negative electrode sheet is a double-layer silicon-based composite negative electrode sheet, and the preparation method comprises the steps of,
ball milling is carried out on the mixture of the nano silicon composite particles and the LATP, and the mixed powder is pressed into a film to obtain a silicon-based film; stirring polymer electrolyte and chlorate electrolyte in an organic solvent until the polymer electrolyte and chlorate electrolyte are fully dissolved, and uniformly coating the obtained mixed solution on one side of a silicon-based film layer to form a polymer solid electrolyte layer; and (5) after vacuum drying, finally preparing the double-layer silicon-based composite negative plate.
7. The negative electrode sheet according to claim 6, wherein,
the mass ratio of the nano silicon composite particles to the LATP is 8-10: 1.0 to 2.0;
the ball milling time is 10-20 minutes;
the pressing condition is that pressing is carried out under 50-200 standard atmospheric pressures;
the thickness of the silicon-based film layer is 50-150 mu m;
the molar ratio of the polymer electrolyte to the chlorate electrolyte is 7-10: 1 to 3;
the temperature of the polymer electrolyte and the chlorate electrolyte is 45-55 ℃ when the polymer electrolyte and the chlorate electrolyte are dissolved in an organic solvent, the stirring time is 3-5 hours, and the organic solvent is one of acetonitrile, methanol, tetrahydrofuran, N-dimethylformamide, dimethyl sulfoxide, diethyl ether and carbon tetrachloride;
the thickness of the polymer solid electrolyte layer is 10-15 mu m;
the temperature of the vacuum drying is 30-40 ℃ and the time is 12-20 hours.
8. The negative electrode sheet according to claim 6, wherein,
the polymer electrolyte is one of polyethylene oxide, polymethacrylic acid, polyurethane, polyvinylidene fluoride, polyacrylonitrile and polymethyl methacrylate;
the chlorate electrolyte is one of cesium perchlorate, lithium perchlorate, sodium perchlorate, potassium perchlorate and rubidium perchlorate.
9. A solid lithium battery comprising the negative electrode sheet of any one of claims 5-8.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106972192A (en) * | 2017-03-16 | 2017-07-21 | 江苏大学 | For the method and electrolytic cell device, lithium-ion energy storage device of the prefabricated lithium of lithium-ion energy storage device negative pole |
| CN109148165A (en) * | 2018-08-01 | 2019-01-04 | 曲阜师范大学 | A kind of preparation and application of covalent organic frame/graphene composite material |
| CN109524652A (en) * | 2018-11-16 | 2019-03-26 | 华南师范大学 | A kind of covalent organic frame/graphene compositing organic material and preparation method and the application in lithium/anode material of lithium-ion battery |
| CN109755534A (en) * | 2019-01-21 | 2019-05-14 | 中国科学院宁波材料技术与工程研究所 | A kind of electrode material and its preparation and application based on organic covalent frame material |
| CN110416500A (en) * | 2019-06-12 | 2019-11-05 | 桑德新能源技术开发有限公司 | A kind of silicon-carbon cathode material and preparation method thereof |
| CN110483799A (en) * | 2019-08-30 | 2019-11-22 | 兰州交通大学 | A kind of controllable method for preparing and its stored energy application based on covalent organic frame |
| CN111430697A (en) * | 2020-05-18 | 2020-07-17 | 新昌县旭辉新材料科技有限公司 | Carbon-coated modified silicon composite lithium ion battery cathode material and preparation method thereof |
| CN111682173A (en) * | 2020-06-03 | 2020-09-18 | 湖南大学 | Composite material of multi-heteroatom co-doped carbon shell coated silicon and preparation method thereof |
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Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106972192A (en) * | 2017-03-16 | 2017-07-21 | 江苏大学 | For the method and electrolytic cell device, lithium-ion energy storage device of the prefabricated lithium of lithium-ion energy storage device negative pole |
| CN109148165A (en) * | 2018-08-01 | 2019-01-04 | 曲阜师范大学 | A kind of preparation and application of covalent organic frame/graphene composite material |
| CN109524652A (en) * | 2018-11-16 | 2019-03-26 | 华南师范大学 | A kind of covalent organic frame/graphene compositing organic material and preparation method and the application in lithium/anode material of lithium-ion battery |
| CN109755534A (en) * | 2019-01-21 | 2019-05-14 | 中国科学院宁波材料技术与工程研究所 | A kind of electrode material and its preparation and application based on organic covalent frame material |
| CN110416500A (en) * | 2019-06-12 | 2019-11-05 | 桑德新能源技术开发有限公司 | A kind of silicon-carbon cathode material and preparation method thereof |
| CN110483799A (en) * | 2019-08-30 | 2019-11-22 | 兰州交通大学 | A kind of controllable method for preparing and its stored energy application based on covalent organic frame |
| CN111430697A (en) * | 2020-05-18 | 2020-07-17 | 新昌县旭辉新材料科技有限公司 | Carbon-coated modified silicon composite lithium ion battery cathode material and preparation method thereof |
| CN111682173A (en) * | 2020-06-03 | 2020-09-18 | 湖南大学 | Composite material of multi-heteroatom co-doped carbon shell coated silicon and preparation method thereof |
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