CN113460991A - Self-supporting porous lithium titanate composite precursor, negative electrode material thereof and preparation method - Google Patents
Self-supporting porous lithium titanate composite precursor, negative electrode material thereof and preparation method Download PDFInfo
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- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 61
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 61
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 title claims abstract description 50
- 239000002131 composite material Substances 0.000 title claims abstract description 38
- 239000002243 precursor Substances 0.000 title claims abstract description 28
- 239000007773 negative electrode material Substances 0.000 title claims abstract description 24
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 35
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims abstract description 33
- 229910021389 graphene Inorganic materials 0.000 claims abstract description 21
- 239000002002 slurry Substances 0.000 claims abstract description 20
- 238000000034 method Methods 0.000 claims abstract description 19
- 239000006260 foam Substances 0.000 claims abstract description 17
- 229920000877 Melamine resin Polymers 0.000 claims abstract description 13
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 claims abstract description 13
- 239000004408 titanium dioxide Substances 0.000 claims abstract description 13
- 238000000498 ball milling Methods 0.000 claims abstract description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000008367 deionised water Substances 0.000 claims abstract description 7
- 229910021641 deionized water Inorganic materials 0.000 claims abstract description 7
- 238000001035 drying Methods 0.000 claims abstract description 7
- 238000000265 homogenisation Methods 0.000 claims abstract description 6
- 239000011148 porous material Substances 0.000 claims abstract description 6
- 238000002791 soaking Methods 0.000 claims abstract description 6
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- 238000005303 weighing Methods 0.000 claims abstract description 3
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- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 claims description 6
- IIPYXGDZVMZOAP-UHFFFAOYSA-N lithium nitrate Chemical compound [Li+].[O-][N+]([O-])=O IIPYXGDZVMZOAP-UHFFFAOYSA-N 0.000 claims description 6
- 239000012298 atmosphere Substances 0.000 claims description 4
- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical compound [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 claims description 4
- 239000000654 additive Substances 0.000 claims description 3
- 230000000996 additive effect Effects 0.000 claims description 3
- XIXADJRWDQXREU-UHFFFAOYSA-M lithium acetate Chemical compound [Li+].CC([O-])=O XIXADJRWDQXREU-UHFFFAOYSA-M 0.000 claims description 3
- 229910052808 lithium carbonate Inorganic materials 0.000 claims description 3
- 150000001875 compounds Chemical class 0.000 claims description 2
- YNQRWVCLAIUHHI-UHFFFAOYSA-L dilithium;oxalate Chemical compound [Li+].[Li+].[O-]C(=O)C([O-])=O YNQRWVCLAIUHHI-UHFFFAOYSA-L 0.000 claims description 2
- 239000007891 compressed tablet Substances 0.000 claims 1
- 239000000463 material Substances 0.000 abstract description 35
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 abstract description 10
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- 239000013543 active substance Substances 0.000 description 5
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- CZMRCDWAGMRECN-UGDNZRGBSA-N Sucrose Chemical compound O[C@H]1[C@H](O)[C@@H](CO)O[C@@]1(CO)O[C@@H]1[C@H](O)[C@@H](O)[C@H](O)[C@@H](CO)O1 CZMRCDWAGMRECN-UGDNZRGBSA-N 0.000 description 2
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- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- 229910009866 Ti5O12 Inorganic materials 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
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- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
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- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
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- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G23/00—Compounds of titanium
- C01G23/003—Titanates
- C01G23/005—Alkali titanates
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- 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
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- 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
- H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
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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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
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Abstract
A self-supporting porous lithium titanate composite precursor, a negative electrode material thereof and a preparation method are provided, wherein the preparation method of the precursor comprises the following steps: weighing titanium dioxide, a lithium source and graphene oxide, dispersing in deionized water, and performing ball milling, ultrasonic and high-speed homogenization to obtain slurry A; and soaking melamine foam serving as a structural framework into the slurry A, fully filling the slurry A into foam pores, drying, and tabletting under certain pressure to obtain the self-supporting porous lithium titanate composite precursor. The method is characterized in that an integrated porous lithium titanate negative electrode material is constructed, and the electronic conductivity and the lithium ion diffusion rate of the material can be improved simultaneously. Under the same test conditions, the battery performance of the composite negative electrode material is obviously superior to that of the conventional lithium titanate material. Meanwhile, the method can omit a coating process and can be directly used as a battery pole piece without a conductive agent, a binder and a current collector, so that the cost is low, the method is more environment-friendly, and the manufactured pole piece has higher energy density.
Description
Technical Field
The invention relates to the field of lithium ion battery materials, in particular to a preparation method of a lithium ion battery cathode material with high energy density.
Background
With the trend of miniaturization of electrical equipment becoming more and more obvious, more and more equipment need rely on lithium ion battery for energy supply. However, for some high-power devices, it is often required that the battery can discharge with a large current under the condition of ensuring safety, and the battery has a long cycle life under the working condition. Lithium ion batteries based on traditional electrode materials are often difficult to take into account all of the above properties and cannot be widely applied to high-power equipment.
Lithium titanate (Li)4Ti5O12) The material is a zero-strain lithium ion battery cathode material, and due to a unique lithium ion de-intercalation mechanism, the high-rate charge and discharge performance of the material is very outstanding in the currently known materials; in addition, the crystal structure has high stability in battery operation, and the lattice parameter of the whole charge and discharge process is hardly changed, so that the battery has excellent cycle stability. The lithium titanate has higher lithium intercalation potential (1.55V vs. Li/Li)+) The growth of negative pole lithium dendrite and the battery short circuit that leads to from this can be avoided, the security performance of battery is promoted by a wide margin. However, lithium titanate is an insulator with an intrinsic electron conductivity of only 10-7S/m, electrons are very slowly transmitted to the inside of the collector through the collector, so that severe electrode polarization is caused, and the high-rate charge and discharge performance of the collector is influenced. In addition, the theoretical specific capacity of lithium titanate is only 175mAh/g, so that the energy density of the pole piece prepared by matching with a metal current collector is very low.
The melamine foam is flexible polymer foam, the interior of the melamine foam has rich pore structures, the melamine foam has thermosetting property, and the conductive carbon skeleton with original porous morphology is obtained after high-temperature treatment in inert atmosphere. In addition, the functional group in the molecular structure can be combined with titanium dioxide, which is beneficial to the adhesion of titanium dioxide on the surface of the titanium dioxide, and further obviously improves the electronic conduction performance of the final composite material.
Graphene is a two-dimensional carbon material with an infinitely expanding regular hexagonal "honeycomb" lattice structure. Based on the particularity of the molecular structure of the graphene material, the graphene material has the characteristics of high conductivity, high specific surface area, high mechanical strength and the like, and is very suitable for the fields of microelectronics, energy storage devices and the like. Graphene oxide is a graphene derivative obtained by chemically oxidizing and exfoliating graphite, and can also be regarded as a single-layer carbon material. In contrast, a large number of carbon atoms in graphene oxide are converted from sp2 hybridization to sp3 hybridization and are connected with functional groups such as carboxyl and epoxy groups, so that the graphene oxide has excellent dispersibility in water, can react with transition metal ions and substances containing polar groups, is very easy to adsorb, modify and load mutually, and is easy to stack between sheets to form a continuous structure, but the molecular structure also determines that the conductivity of the material is poor. Under certain conditions, graphene oxide can be reduced into graphene through high-temperature treatment, and the conductive performance of the graphene oxide is recovered while the morphological characteristics of the two-dimensional material are kept. Based on the characteristics, the graphene oxide is very suitable to be used as a construction material of a continuous conductive framework, and is beneficial to ensuring that the electronic conduction is smoother while the mechanical property of the material is enhanced.
The lithium titanate with extremely low electronic conductivity is compounded with the carbon material with high conductivity, so that the electronic transmission of the whole electrode can be improved, the lithium titanate/carbon composite material is prepared in many research works, and the rate capability of the material is effectively improved. However, the conductive carbon skeleton in the material is connected in a point-to-point manner to a great extent, so that a three-dimensional conductive network with a continuous and stable structure and good contact is difficult to construct in the material, and the further improvement of the rate capability of the lithium titanate material is limited. In addition, the material can only adopt the traditional processes of homogenizing, coating and drying to prepare the pole piece, the proportion of lithium titanate active substances in the pole piece is very low, and the theoretical capacity of lithium titanate is low, so that the overall energy density of the pole piece is very low, and the pole piece is difficult to adapt to the trend of equipment miniaturization.
Disclosure of Invention
In order to solve the technical problems, the invention provides a self-supporting porous lithium titanate composite precursor, a negative electrode material and a preparation method thereof. According to the method, a highly continuous porous carbon skeleton is constructed in the material, so that the electronic conductivity of the material is improved, lithium ion transmission is facilitated, the material can be directly used as a pole piece without a binder and a current collector, and the energy density of an electrode is greatly improved. The method has the advantages of novel preparation process, low raw material cost and environment-friendly and safe synthetic route.
In order to achieve the technical effects, the invention provides the following technical scheme:
the preparation method of the self-supporting porous lithium titanate composite precursor is characterized by comprising the following steps: weighing titanium dioxide, a lithium source and graphene oxide, dispersing in deionized water, and performing ball milling, ultrasonic and high-speed homogenization to obtain slurry A; and soaking melamine foam serving as a structural framework into the slurry A, fully filling the slurry A into foam pores, drying, and tabletting under certain pressure to obtain the self-supporting porous lithium titanate composite precursor.
The titanium dioxide is one or more of rutile type, anatase type and amorphous type.
The crystal form of the titanium dioxide is preferably anatase.
The ball milling rotating speed is 300-500 r/min.
The high-speed homogenizing rotating speed is 1200-2000 r/min.
The compound of the lithium source is one or more of lithium carbonate, lithium nitrate, lithium acetate, lithium oxalate and lithium hydroxide.
The graphene oxide is a structure-enhancing additive and accounts for 1-10% of the total mass of the solid.
The solid content of the slurry A is 10-40%.
The tabletting pressure is 5-10 Mpa.
The precursor is prepared by the preparation method.
And roasting the precursor at high temperature in an inert atmosphere to obtain the self-supporting porous lithium titanate composite negative electrode material.
The roasting temperature is 700-900 ℃, and the roasting time is 6-12 h.
The negative electrode material is prepared by the preparation method disclosed by the invention.
Compared with the prior art, the invention has the following beneficial effects:
1. the method is characterized in that the interaction between functional groups and the interaction between functional groups and ions are utilized, melamine foam is used as a basic structure template, graphene oxide is used as an additive for improving mechanical properties, an integrated porous carbon conductive framework is constructed, lithium titanate is uniformly distributed in a pore structure of the framework, an internal continuous pore structure is favorable for the transmission of lithium ions, the integral electronic conductivity and the lithium ion diffusion rate of the material are greatly improved, the multiplying power performance of the material is obviously improved, and the manufactured pole piece has higher energy density.
2. The lithium titanate particles are tightly combined with the framework structure, the structure can realize an integrated self-supporting electrode, the method can omit a coating process, and the lithium titanate particles can be directly used as a battery pole piece, a conductive agent, a binder and a current collector are not needed, and the pole piece manufacturing process is simplified, so that the cost is low, and the lithium titanate particles are more environment-friendly.
3. According to the invention, through further optimizing and setting the parameters of the preparation process method, such as the mass ratio of the graphene oxide, the solid content of the slurry A, the tabletting pressure, the roasting temperature and time of the precursor and the like, the multiplying power of the negative electrode material is improved, the energy density of the pole piece is improved, the product yield is improved, the impurity phase is reduced, the cost is reduced and the like.
The specific implementation mode is as follows:
the present invention will be further described with reference to the following specific examples, which should not be construed as limiting the scope of the invention, but rather as providing those skilled in the art with certain insubstantial modifications and adaptations of the invention based on the teachings of the invention set forth herein.
Drawings
Fig. 1 is a digital photograph of a self-supporting porous lithium titanate composite negative electrode material in example 1.
Fig. 2 and 3 are SEM images of the self-supporting porous lithium titanate composite negative electrode material in example 1.
Fig. 4 is an XRD spectrum of the self-supporting porous lithium titanate composite negative electrode material of example 1.
Fig. 5 shows the half-cell cycling of different materials (specific capacity calculated based on active mass).
Fig. 6 shows the half-cell cycling of different materials (specific capacity was calculated based on the overall mass of the negative plate).
Example 1
The embodiment provides a preparation method of a self-supporting porous lithium titanate composite negative electrode material, which specifically comprises the following steps:
(1) adding 0.9g of titanium dioxide (anatase type), 0.2g of lithium carbonate and 0.015g of graphene oxide into 10mL of deionized water, and performing ball milling for 1h at 500r/min, ultrasonic processing for 30min and high-speed homogenizing for 1200r/min to obtain slurry A with the solid content of 30%;
(2) soaking melamine foam into the slurry A, taking out and drying after the melamine foam is fully soaked, and tabletting under the pressure of 7Mpa to obtain a precursor B;
(3) roasting the precursor B at the high temperature of 800 ℃ for 10 hours in the nitrogen atmosphere to obtain a self-supporting porous lithium titanate composite negative electrode material;
the electrochemical performance test of the prepared self-supporting porous lithium titanate composite negative electrode material comprises the following specific steps: the material is directly used as a pole piece after being cut; the electrode plate is used as a working electrode, a metal lithium plate is used as a counter electrode, and 1M LiPF6Dissolution in EC: DMC 1:1 as electrolyte, assembling a button type half cell for performance test, wherein a charge-discharge potential window is 1-2.5V; test results show that under the multiplying power of 0.5C, 1C and 10C, the discharge specific capacity of the material reaches 172mAh/g, 171mAh/g and 153mAh/g respectively, and the integral specific capacity of a negative pole piece (except the mass of carbon, the active substance accounts for about 90%) is 153mAh/g, 152mAh/g and 136mAh/g respectively, so that the material has good multiplying power performance and high full-cell energy density.
Example 2
(1) Adding 2g of titanium dioxide (rutile type), 1g of lithium nitrate and 0.33g of graphene oxide into 5mL of deionized water, and performing ball milling for 1h at 300r/min, ultrasonic grinding for 30min and high-speed homogenization at 2000r/min to obtain slurry A with the solid content of 10%;
(2) soaking melamine foam into the slurry A, taking out and drying after the melamine foam is fully soaked, and tabletting under the pressure of 5Mpa to obtain a precursor B;
(3) roasting the precursor B at the high temperature of 900 ℃ for 6 hours in a nitrogen atmosphere to obtain a self-supporting porous lithium titanate composite negative electrode material;
the electrochemical performance test of the prepared self-supporting porous lithium titanate composite negative electrode material comprises the following specific steps: the material is directly used as a pole piece after being cut; the electrode plate is used as a working electrode, a metal lithium plate is used as a counter electrode, and 1M LiPF6Dissolution in EC: DMC 1:1 as electrolyte, assembling a button type half cell for performance test, wherein a charge-discharge potential window is 1-2.5V; test results show that under the multiplying power of 0.5C, 1C and 10C, the discharge specific capacity of the material respectively reaches 152mAh/g, 149mAh/g and 143mAh/g, and the integral specific capacity of a negative pole piece (except the mass of carbon, the active substance accounts for about 90%) respectively reaches 135mAh/g, 132mAh/g and 127mAh/g, so that the material has good multiplying power performance and high full-cell energy density.
Example 3
(1) Adding 1g of titanium dioxide (amorphous), 0.38g of lithium acetate and 0.08g of graphene oxide into 3mL of deionized water, and performing ball milling for 1h at 300r/min, ultrasonic homogenization for 30min and high-speed homogenization at 2000r/min to obtain slurry A with the solid content of 32.7%;
(2) soaking melamine foam into the slurry A, taking out and drying after the melamine foam is fully soaked, and tabletting under the pressure of 10Mpa to obtain a precursor B;
(3) roasting the precursor B at a high temperature of 700 ℃ for 12 hours in a nitrogen atmosphere to obtain a self-supporting porous lithium titanate composite negative electrode material;
the electrochemical performance test of the prepared self-supporting porous lithium titanate composite negative electrode material comprises the following specific steps: the material is directly used as a pole piece after being cut; the electrode plate is used as a working electrode, a metal lithium plate is used as a counter electrode, and 1M LiPF6Dissolved in EC: DMC 1:1 as electrolyte, assembling a button type half cell for performance test, wherein a charge-discharge potential window is 1-2.5V; test results show that under the multiplying power of 0.5C, 1C and 10C, the discharge specific capacity of the material respectively reaches 168mAh/g, 167mAh/g and 164mAh/g, and the integral specific capacity of a negative pole piece (except the mass of carbon, the active substance accounts for about 90%) respectively reaches 150mAh/g, 149mAh/g and 146mAh/g, so that the material has good multiplying power performance and high full-cell energy density.
Comparative example 1
The preparation method of the conventional lithium titanate/carbon composite material specifically comprises the following steps:
(1) adding 0.1g of sucrose into 10mL of deionized water, and stirring until the sucrose is completely dissolved to obtain a solution A;
(2) adding 1g of titanium dioxide and 0.38g of lithium carbonate powder into the solution A, and performing ball milling for 1h at the rotating speed of 600r/min to obtain slurry B;
(4) spray drying the slurry B to obtain precursor powder C;
(5) and (3) placing the precursor powder C in a tube furnace, and roasting for 10h at 800 ℃ under an inert atmosphere to obtain the lithium titanate/carbon composite material.
The prepared graphene/carbon-coated doped lithium titanate composite material is subjected to electrochemical performance test, and the specific steps are as follows: uniformly dispersing a lithium titanate/carbon composite material, carbon black and PVDF in a mass ratio of 8:1:1 in N-methylpyrrolidone to prepare electrode slurry, uniformly coating the electrode slurry on a copper foil, and performing vacuum drying at 110 ℃ for 12 hours to prepare a pole piece; the electrode plate is used as a working electrode, a metal lithium plate is used as a counter electrode, and 1M LiPF6Dissolution in EC: DMC 1:1 as electrolyte, assembling a button type half cell for performance test, wherein a charge-discharge potential window is 1-2.5V; test results show that under the multiplying power of 0.5C, 1C and 10C, the specific discharge capacity of the material is 161mAh/g, 156mAh/g and 131mAh/g respectively, the overall specific capacity of a negative pole piece (based on single-side coating on copper foil, the active substance accounts for about 26%) is 42mAh/g, 41mAh/g and 35mAh/g respectively, and compared with the self-supporting porous lithium titanate composite negative pole material prepared by the method, the multiplying power performance and the full battery energy density are poor.
The comparison of the above embodiments shows that the electrode manufactured by the method of the present invention has excellent rate performance and higher energy density of the whole battery compared with the electrode manufactured by the material manufactured by the existing method, and the method can omit the coating process, directly use as the battery pole piece, does not need a conductive agent, a binder and a current collector, simplifies the pole piece manufacturing process, and is low in cost and more environment-friendly.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that are within the spirit and principle of the present invention are intended to be included in the scope of the present invention.
Claims (10)
1. The preparation method of the self-supporting porous lithium titanate composite precursor is characterized by comprising the following steps: weighing titanium dioxide, a lithium source and graphene oxide, dispersing in deionized water, and performing ball milling, ultrasonic and high-speed homogenization to obtain slurry A; and soaking melamine foam serving as a structural framework into the slurry A, fully filling the slurry A into foam pores, drying, and tabletting to obtain the self-supporting porous lithium titanate composite precursor.
2. The method of preparing the self-supporting porous lithium titanate composite precursor of claim 1, wherein the titanium dioxide is one or more of rutile, anatase, and amorphous.
3. The method of preparing the self-supporting porous lithium titanate composite precursor of claim 1, wherein the compound of the lithium source is one or more of lithium carbonate, lithium nitrate, lithium acetate, lithium oxalate, and lithium hydroxide.
4. The method for preparing the self-supporting porous lithium titanate composite precursor as claimed in claim 1, wherein the graphene oxide is a structure-enhancing additive and accounts for 1-10% of the total mass of the solid.
5. The method for preparing the self-supporting porous lithium titanate composite precursor of claim 1, wherein the slurry a has a solid content of 10% to 40%.
6. The method for preparing the self-supporting porous lithium titanate composite precursor according to claim 1, wherein the pressure of the compressed tablet is 5-10 Mpa.
7. A self-supporting porous lithium titanate composite precursor is characterized by being prepared by the preparation method of any one of claims 1-6.
8. The preparation method of the self-supporting porous lithium titanate composite negative electrode material is characterized in that the precursor is roasted at high temperature in an inert atmosphere to obtain the self-supporting porous lithium titanate composite negative electrode material.
9. The preparation method of the self-supporting porous lithium titanate composite negative electrode material of claim 8, wherein the roasting temperature is 700-900 ℃, and the roasting time is 6-12 hours.
10. The self-supporting porous lithium titanate composite negative electrode material is characterized in that the negative electrode material is prepared by the preparation method of any one of claims 8 to 9.
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| CN103022460A (en) * | 2012-11-28 | 2013-04-03 | 上海锦众信息科技有限公司 | Method for preparing lithium titanate carbon composite material |
| CN108417798A (en) * | 2018-02-09 | 2018-08-17 | 复旦大学 | A kind of ZnO nano piece/carbon sponge flexible compound negative material and preparation method thereof |
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| CN103022460A (en) * | 2012-11-28 | 2013-04-03 | 上海锦众信息科技有限公司 | Method for preparing lithium titanate carbon composite material |
| CN108417798A (en) * | 2018-02-09 | 2018-08-17 | 复旦大学 | A kind of ZnO nano piece/carbon sponge flexible compound negative material and preparation method thereof |
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