CN115676888B - Modified lithium tantalate modified graphene nanomaterial and preparation method and application thereof - Google Patents
Modified lithium tantalate modified graphene nanomaterial and preparation method and application thereof Download PDFInfo
- Publication number
- CN115676888B CN115676888B CN202211444560.7A CN202211444560A CN115676888B CN 115676888 B CN115676888 B CN 115676888B CN 202211444560 A CN202211444560 A CN 202211444560A CN 115676888 B CN115676888 B CN 115676888B
- Authority
- CN
- China
- Prior art keywords
- modified
- lithium
- lithium tantalate
- stirring
- solution
- 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
Links
- -1 Modified lithium tantalate modified graphene Chemical class 0.000 title claims abstract description 26
- 239000002086 nanomaterial Substances 0.000 title claims abstract description 24
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 85
- 229910021389 graphene Inorganic materials 0.000 claims abstract description 82
- WSMQKESQZFQMFW-UHFFFAOYSA-N 5-methyl-pyrazole-3-carboxylic acid Chemical class CC1=CC(C(O)=O)=NN1 WSMQKESQZFQMFW-UHFFFAOYSA-N 0.000 claims abstract description 75
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 45
- 229910052723 transition metal Inorganic materials 0.000 claims abstract description 7
- 239000000126 substance Substances 0.000 claims abstract description 4
- 238000003756 stirring Methods 0.000 claims description 96
- 239000000243 solution Substances 0.000 claims description 88
- 239000000843 powder Substances 0.000 claims description 63
- 239000011259 mixed solution Substances 0.000 claims description 47
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical group CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 40
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 claims description 34
- 239000002184 metal Substances 0.000 claims description 24
- 239000002904 solvent Substances 0.000 claims description 24
- 229910052751 metal Inorganic materials 0.000 claims description 23
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 22
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 22
- 238000000227 grinding Methods 0.000 claims description 22
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 20
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims description 18
- BPUBBGLMJRNUCC-UHFFFAOYSA-N oxygen(2-);tantalum(5+) Chemical group [O-2].[O-2].[O-2].[O-2].[O-2].[Ta+5].[Ta+5] BPUBBGLMJRNUCC-UHFFFAOYSA-N 0.000 claims description 18
- 229910001936 tantalum oxide Inorganic materials 0.000 claims description 18
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 15
- 238000010438 heat treatment Methods 0.000 claims description 15
- 238000001816 cooling Methods 0.000 claims description 13
- 238000001035 drying Methods 0.000 claims description 13
- 238000002156 mixing Methods 0.000 claims description 13
- 229910052786 argon Inorganic materials 0.000 claims description 11
- 238000001354 calcination Methods 0.000 claims description 11
- 229910052757 nitrogen Inorganic materials 0.000 claims description 11
- 229910052715 tantalum Inorganic materials 0.000 claims description 11
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 claims description 11
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 claims description 9
- NGCRLFIYVFOUMZ-UHFFFAOYSA-N 2,3-dichloroquinoxaline-6-carbonyl chloride Chemical compound N1=C(Cl)C(Cl)=NC2=CC(C(=O)Cl)=CC=C21 NGCRLFIYVFOUMZ-UHFFFAOYSA-N 0.000 claims description 8
- XIXADJRWDQXREU-UHFFFAOYSA-M lithium acetate Chemical compound [Li+].CC([O-])=O XIXADJRWDQXREU-UHFFFAOYSA-M 0.000 claims description 8
- 229910003002 lithium salt Inorganic materials 0.000 claims description 8
- 159000000002 lithium salts Chemical class 0.000 claims description 8
- 150000003839 salts Chemical class 0.000 claims description 8
- 239000011230 binding agent Substances 0.000 claims description 6
- OEIMLTQPLAGXMX-UHFFFAOYSA-I tantalum(v) chloride Chemical compound Cl[Ta](Cl)(Cl)(Cl)Cl OEIMLTQPLAGXMX-UHFFFAOYSA-I 0.000 claims description 6
- 150000001875 compounds Chemical class 0.000 claims description 4
- 229940071264 lithium citrate Drugs 0.000 claims description 4
- WJSIUCDMWSDDCE-UHFFFAOYSA-K lithium citrate (anhydrous) Chemical compound [Li+].[Li+].[Li+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O WJSIUCDMWSDDCE-UHFFFAOYSA-K 0.000 claims description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 claims description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 2
- 229910002651 NO3 Inorganic materials 0.000 claims description 2
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 claims description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 2
- 239000003575 carbonaceous material Substances 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 33
- 239000000463 material Substances 0.000 abstract description 20
- 230000008021 deposition Effects 0.000 abstract description 8
- 230000008569 process Effects 0.000 abstract description 7
- 210000001787 dendrite Anatomy 0.000 abstract description 6
- 238000007086 side reaction Methods 0.000 abstract description 6
- 238000006243 chemical reaction Methods 0.000 abstract description 5
- 239000002131 composite material Substances 0.000 description 43
- 230000001681 protective effect Effects 0.000 description 36
- 238000012360 testing method Methods 0.000 description 32
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 24
- 229910001416 lithium ion Inorganic materials 0.000 description 24
- 238000009833 condensation Methods 0.000 description 19
- 230000005494 condensation Effects 0.000 description 19
- 230000014759 maintenance of location Effects 0.000 description 18
- 238000004458 analytical method Methods 0.000 description 15
- 238000000921 elemental analysis Methods 0.000 description 15
- YQCIWBXEVYWRCW-UHFFFAOYSA-N methane;sulfane Chemical compound C.S YQCIWBXEVYWRCW-UHFFFAOYSA-N 0.000 description 15
- 230000000052 comparative effect Effects 0.000 description 12
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 11
- KBJMLQFLOWQJNF-UHFFFAOYSA-N nickel(ii) nitrate Chemical compound [Ni+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O KBJMLQFLOWQJNF-UHFFFAOYSA-N 0.000 description 10
- 230000002572 peristaltic effect Effects 0.000 description 9
- 238000000151 deposition Methods 0.000 description 7
- 239000002033 PVDF binder Substances 0.000 description 5
- 239000003792 electrolyte Substances 0.000 description 5
- 230000004048 modification Effects 0.000 description 5
- 238000012986 modification Methods 0.000 description 5
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- 239000011572 manganese Substances 0.000 description 4
- 239000011268 mixed slurry Substances 0.000 description 4
- 239000007773 negative electrode material Substances 0.000 description 4
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 4
- 238000011160 research Methods 0.000 description 4
- DHEQXMRUPNDRPG-UHFFFAOYSA-N strontium nitrate Chemical compound [Sr+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O DHEQXMRUPNDRPG-UHFFFAOYSA-N 0.000 description 4
- ONDPHDOFVYQSGI-UHFFFAOYSA-N zinc nitrate Chemical compound [Zn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ONDPHDOFVYQSGI-UHFFFAOYSA-N 0.000 description 4
- 229920002799 BoPET Polymers 0.000 description 3
- 239000005041 Mylar™ Substances 0.000 description 3
- 239000006258 conductive agent Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000012528 membrane Substances 0.000 description 3
- 238000001291 vacuum drying Methods 0.000 description 3
- 239000011701 zinc Substances 0.000 description 3
- OTYYBJNSLLBAGE-UHFFFAOYSA-N CN1C(CCC1)=O.[N] Chemical compound CN1C(CCC1)=O.[N] OTYYBJNSLLBAGE-UHFFFAOYSA-N 0.000 description 2
- 239000010405 anode material Substances 0.000 description 2
- 210000004027 cell Anatomy 0.000 description 2
- FUJCRWPEOMXPAD-UHFFFAOYSA-N lithium oxide Chemical compound [Li+].[Li+].[O-2] FUJCRWPEOMXPAD-UHFFFAOYSA-N 0.000 description 2
- 229910001947 lithium oxide Inorganic materials 0.000 description 2
- 229910021645 metal ion Inorganic materials 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 230000010287 polarization Effects 0.000 description 2
- 239000007774 positive electrode material Substances 0.000 description 2
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- SBLRHMKNNHXPHG-UHFFFAOYSA-N 4-fluoro-1,3-dioxolan-2-one Chemical compound FC1COC(=O)O1 SBLRHMKNNHXPHG-UHFFFAOYSA-N 0.000 description 1
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 description 1
- 229910018068 Li 2 O Inorganic materials 0.000 description 1
- 229910013733 LiCo Inorganic materials 0.000 description 1
- AFCARXCZXQIEQB-UHFFFAOYSA-N N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CCNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 AFCARXCZXQIEQB-UHFFFAOYSA-N 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 239000006230 acetylene black Substances 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 description 1
- 238000004070 electrodeposition Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- MIVBAHRSNUNMPP-UHFFFAOYSA-N manganese(2+);dinitrate Chemical compound [Mn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MIVBAHRSNUNMPP-UHFFFAOYSA-N 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 229910021382 natural graphite Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910000480 nickel oxide Inorganic materials 0.000 description 1
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 description 1
- 238000002161 passivation Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 238000006722 reduction reaction Methods 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
- 229910001961 silver nitrate Inorganic materials 0.000 description 1
- 239000007784 solid electrolyte Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000009210 therapy by ultrasound Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Battery Electrode And Active Subsutance (AREA)
Abstract
The invention discloses a modified lithium tantalate modified graphene nanomaterial and a preparation method and application thereof, and belongs to the technical field of lithium metal negative electrode protection materials. The technical proposal is as follows: the chemical formula of the modified lithium tantalate is LiM x Ta 1‑x O 3 M is one or more transition metal elements, and x is more than or equal to 0 and less than or equal to 0.5. The invention effectively solves the problem of poor cycle performance caused by dendrite growth in the cycle process of the lithium metal anode, and improves the cycle performance by about 104% at most compared with the anode using graphene only; the lithium tantalate on the surface of the graphene also provides a large number of active sites for lithium metal conversion and deposition, so that side reactions of lithium metal in the charge-discharge process are further reduced, and the stability and the rate capability of the electrode are improved.
Description
Technical Field
The invention relates to the technical field of lithium metal negative electrode protection materials, in particular to a modified lithium tantalate modified graphene nanomaterial and a preparation method thereof.
Background
Along with the wide application of lithium ion batteries in the fields of mobile equipment, electric automobiles and the like, people put higher requirements on the energy density and the power density of lithium ions. The development and research of the anode material are gradually perfected, so that the overall performance of the lithium ion battery is improved, and the research of the high-performance anode material has great prospect. Metallic lithium, which has the advantages of high specific capacity, light weight, low potential and the like, is often considered as a final lithium ion battery negative electrode material. However, lithium metal secondary batteries have not been commercialized, and the main reasons include: 1) Lithium dendrites are easy to generate in the cycle of the battery, and puncture the diaphragm, so that the battery is short-circuited, heat failure is caused, and even fire or explosion is caused, thus potential safety problems are caused; 2) The lithium anode belongs to a non-host substrate, and can generate infinite volume expansion in the electrodeposition process, so that the anode structure is loose and collapses; 3) The dendrite and loose cathode structure produced increases the specific surface of the cathode, resulting in an increase in the contact area of metallic lithium with electrolyte, producing more solid electrolyte membranes (SEI), and the fragile SEI produces a large amount of "dead lithium" during the continuous cracking and repair process. In addition, since lithium metal has high electrochemical activity, a large specific surface area increases side reactions, thereby continuously reducing battery capacity. In general, lithium metal is limited in its commercial applications due to the fact that dendrites are easily generated during battery cycling, infinite volume expansion, extremely active chemical properties, and severe side reaction phenomena, resulting in safety problems and practical problems of rapid capacity decay of the battery itself. The current research on metallic lithium electrodes has mostly focused on the following aspects: modification of electrolyte, surface passivation modification or artificial protection layer, design of a 'structured' composite metal lithium electrode and induced deposition of a heterogeneous matrix. Although the service life of the lithium battery is prolonged to a certain extent and the cycle performance of the battery is improved, the problems of poor stability, poor rate performance and the like exist in the above aspects.
Disclosure of Invention
The invention aims to solve the technical problems that: the defect of the prior art is overcome, and the modified lithium tantalate modified graphene nanomaterial, the preparation method and the application thereof are provided, so that the problem that the cycle performance is poor due to dendrite growth in the cycle process of a lithium metal negative electrode is effectively solved, and compared with the negative electrode only using graphene, the cycle performance is improved by about 104% at most; the lithium tantalate on the surface of the graphene also provides a large number of active sites for lithium metal conversion and deposition, so that side reactions of lithium metal in the charge-discharge process are further reduced, and the stability and the rate capability of the electrode are improved.
The technical scheme of the invention is as follows:
in a first aspect, the invention provides a modified lithium tantalate modified graphene nanomaterial, wherein the chemical formula of the modified lithium tantalate is LiM x Ta 1-x O 3 M is one or more transition metal elements, and x is more than or equal to 0 and less than or equal to 0.5; preferably M is Ni 2+ 、Mn 2+ 、Ag + 、Zn 2+ And Sr 3+ One or more of the following.
In a second aspect, the invention also provides a preparation method of the modified lithium tantalate modified graphene nanomaterial, which comprises the following steps:
1) Adding a tantalum source into a volatile solvent, stirring to dissolve the tantalum source, preparing a solution, and stirring for later use;
2) Dissolving lithium salt in a volatile solvent, and stirring to form a solution;
3) Dispersing graphene in a volatile solvent, and stirring to form a solution;
4) Stirring and mixing the solution in the step 1) and the solution in the step 3) uniformly, heating, condensing and circulating, and stirring to obtain a mixed solution;
5) Dropwise adding the solution obtained in the step 2) into the mixed solution obtained in the step 4), and continuously condensing, circulating and stirring after the dropwise adding is completed to obtain a mixed solution;
6) Stirring and heating the mixed solution obtained in the step 5) until the volatile solvent is completely volatilized to obtain powder, and drying and grinding the powder to obtain powder;
7) Calcining the powder obtained in the step 6) under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding to obtain the powder, thus obtaining the modified lithium tantalate modified graphene nanomaterial.
Preferably, the volatile solvent is ethanol, methanol, isopropanol, N-methyl-2-pyrrolidone (NMP).
Preferably, the metal M compound is added to the volatilizationPreparing a solution by adding the solution into the sex solvent dropwise together with the solution B into the mixed solution obtained in the step 4); wherein the metal M compound is one or more of sulfate, nitrate, chloride, acetate and oxide of M, and M is one or more transition metal elements; preferably M is Ni 2+ 、Mn 2+ 、Ag + 、Zn 2+ And Sr 3+ One or more of the following; the tantalum source is tantalum oxide, tantalum chloride or tantalum ethoxide.
Preferably, the molar ratio of the metal M salt to the tantalum source is less than or equal to 1.
Preferably, in step 2), the lithium salt is one or more of lithium hydroxide, lithium acetate and lithium citrate.
Preferably, in step 2), the molar ratio of lithium salt to tantalum element is 1-3:1.
preferably, in the step 3), the mass ratio of the tantalum element to the graphene is 0.015-0.77:1.
in a third aspect, the invention provides a film comprising the modified lithium tantalate modified graphene nanomaterial, which consists of a binder, a conductive carbon material and the modified lithium tantalate modified graphene nanomaterial.
In a fourth aspect, the present invention provides the use of the film as described above as a lithium electrode protection component for use in a lithium battery
Compared with the prior art, the invention has the following beneficial effects:
1. the modified lithium tantalate modified graphene nanomaterial effectively solves the problem that the cycle performance is poor due to dendrite growth in the cycle process of a lithium metal negative electrode, and compared with the negative electrode only using graphene, the cycle performance is improved by about 104% at most. Meanwhile, lithium tantalate on the surface of the graphene provides a large number of active sites for lithium metal conversion and deposition, so that side reactions of lithium metal in the charge-discharge process are further reduced, and the stability and the rate capability of the electrode are improved.
2. The invention mixes a small amount of transition metal elements in the material to obtain the modified lithium tantalate graphene material, and forms a composite unit (LiM) of lithium tantalate, functional metal and lithium oxide during working x Ta 1-x O 3 → Li x TaO 3 + M + Li 2 O). The lithium tantalate is favorable for improving the uniformity of metal lithium deposition, the modified metal can form an alloy with the metal lithium, the SEI film quality is improved, and the lithium oxide has the effect of relieving the expansion of the metal lithium, so that the capacity retention rate is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the description of the embodiments or the prior art will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.
Fig. 1 is an XRD pattern of the graphene/lithium tantalate composite material prepared in example 1 and the negative electrode material of comparative example 1, in which G represents graphene, LTO represents lithium tantalate, and TO represents tantalum oxide.
Fig. 2 is an SEM image of the separator material after coating of the graphene/lithium tantalate composite material of example 5.
FIG. 3 is a graph showing the performance (charge-discharge current density 0.5-1 mAhcm) of a lithium symmetric battery assembled from a membrane material prepared from the graphene/lithium tantalate composite of example 5 and a membrane material prepared from the graphene material of comparative example 1 -2 )。
Fig. 4 is the cycle performance (charge-discharge current density 0.1C-0.1C) of a full cell assembled from the film material prepared from the graphene/modified lithium tantalate composite material of example 12, the film material prepared from the graphene/lithium tantalate material of example 1, and the film material prepared from the graphene material of comparative example 1.
Fig. 5 is a schematic diagram of electrochemical reduction reactions occurring in a modified lithium tantalate modified graphene nanomaterial.
Detailed Description
In order to make the technical solution of the present invention better understood by those skilled in the art, the technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.
Uniformly mixing a graphene/modified lithium tantalate composite material and a binder polyvinylidene fluoride (PVDF) in a Nitrogen Methyl Pyrrolidone (NMP) solvent, wherein the mass ratio of the composite material to the binder is 90:10; coating the uniformly mixed slurry on a Mylar film, vacuum drying at 60 ℃ for 12 hours, and taking the protective film off the Mylar film to prepare the protective film.
LiCo is added to 0.1 Ni 0.1 Mn 0.8 O 2 Layered oxide material the positive electrode material is mixed with conductive agent acetylene black and binder polyvinylidene fluoride (PVDF) in Nitrogen Methyl Pyrrolidone (NMP) solvent uniformly, liCo 0.1 Ni 0.1 Mn 0.8 O 2 The mass ratio of the layered oxide material positive electrode material, the conductive agent and the binder is 95.5:2.3:2.2; and coating the uniformly mixed slurry on an aluminum foil, and vacuum drying for 12 hours at 120 ℃ to obtain the lithium ion battery positive plate.
Using the positive electrode plate, the lithium metal negative electrode plate and an electrolyte composed of 2mol/L of solution of ethylene carbonate, dimethyl carbonate and fluoroethylene carbonate of lithium hexafluorophosphate, wherein the volume ratio of the solvent is 1:1:1; and assembling the CR2032 button lithium ion battery. The assembled button cell is subjected to charge and discharge test, and the voltage range is 2.8-4.3V vs. Li + /Li。
In the following examples and comparative examples, a method of assembling a lithium ion battery is described by way of example, but other methods and experimental conditions may be employed by those skilled in the art to accomplish the assembly of a lithium ion battery.
Example 1
1) Adding 0.01mol of tantalum oxide into ethanol, stirring to dissolve the tantalum oxide to prepare a solution A, and stirring for later use;
2) Dissolving 0.03mol of lithium acetate in ethanol, and stirring to form a solution B;
3) Dispersing 40g of graphene in ethanol, and stirring to form a solution C;
4) Stirring and mixing the solution A and the solution C uniformly, heating to 60 ℃ for condensation circulation, and stirring to obtain a mixed solution;
5) Dropwise adding the solution B into the mixed solution obtained in the step 4) at a feeding speed of 10r/min through a peristaltic pump, and continuing to perform condensation circulation stirring at 60 ℃ after the dropwise addition is completed to obtain a mixed solution D;
6) Stirring the mixed solution D at 80 ℃ until the solvent volatilizes completely to obtain powder, drying the powder at 80 ℃ for 12h, and grinding for 30min to obtain powder E;
7) And (3) placing the powder E into a tube furnace, calcining at 700 ℃ for 48 hours under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding for 10min to obtain powder F, thus obtaining the graphene/lithium tantalate composite material.
And preparing a graphene/lithium tantalate composite material 1# by the method, and performing ICP elemental analysis and carbon sulfur instrument test analysis, wherein the mass ratio of lithium tantalate to graphene is 1:9. Preparing a protective film 1# according to the method, assembling the protective film into a CR2032 type button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 195mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 71%.
Example 2
1) Adding 0.01mol of tantalum oxide into methanol, stirring to dissolve the tantalum oxide to prepare a solution A, and stirring for later use;
2) Dissolving 0.03mol of lithium acetate in methanol, and stirring to form a solution B;
3) Dispersing 4.5g of graphene in methanol, and stirring to form a solution C;
4) Stirring and mixing the solution A and the solution C uniformly, heating to 50 ℃ for condensation circulation, and stirring to obtain a mixed solution;
5) Dropwise adding the solution B into the mixed solution obtained in the step 4) at a feeding speed of 5r/min through a peristaltic pump, and continuing to perform condensation circulation stirring at 50 ℃ after the dropwise addition is completed to obtain a mixed solution D;
6) Stirring the mixed solution D at 60 ℃ until the solvent volatilizes completely to obtain powder, drying the powder at 70 ℃ for 8 hours, and grinding for 30 minutes to obtain powder E;
7) And (3) placing the powder E into a tube furnace, calcining for 48 hours at 600 ℃ under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding for 10min to obtain powder F, thus obtaining the graphene/lithium tantalate composite material.
Preparing a graphene/lithium tantalate composite material No. 2 according to the method, and performing ICP elemental analysis and carbon sulfur instrument test analysis, wherein the mass ratio of lithium tantalate to graphene is 1:1. preparing a protective film 2# by the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 194mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 60%.
Example 3
1) Adding 0.01mol of tantalum chloride into isopropanol, stirring to dissolve the tantalum chloride to prepare a solution A, and stirring for later use;
2) Dissolving 0.02mol of lithium hydroxide in isopropanol, and stirring to form a solution B;
3) 115.6g of graphene is dispersed in isopropanol and stirred to form a solution C;
4) Stirring and mixing the solution A and the solution C uniformly, heating to 40 ℃ for condensation circulation, and stirring to obtain a mixed solution;
5) Dropwise adding the solution B into the mixed solution obtained in the step 4) at a feeding speed of 15r/min through a peristaltic pump, and continuing to perform condensation circulation stirring at 40 ℃ after the dropwise addition is completed to obtain a mixed solution D;
6) Stirring the mixed solution D at 100 ℃ until the solvent volatilizes completely to obtain powder, drying the powder at 60 ℃ for 6 hours, and grinding for 30 minutes to obtain powder E;
7) And (3) placing the powder E into a tube furnace, calcining for 24 hours at 500 ℃ under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding for 10min to obtain powder F, thus obtaining the graphene/lithium tantalate composite material.
Preparing a graphene/lithium tantalate composite material 3# by the method, and performing ICP elemental analysis and carbon sulfur instrument test analysis, wherein the mass ratio of the lithium tantalate to the graphene is 1:49. preparing a protective film 3# by the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 195mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 50%.
Comparative examples 1-3 show that the mass ratio of graphene to lithium tantalate added is most suitably 9, probably because the material produced at this mass ratio has the best catalytic activity. The addition amount of lithium tantalate is too small, and the active sites for lithium metal transformation are small; too much lithium tantalate may increase polarization of lithium metal and deteriorate performance.
Example 4
1) Adding 0.01mol of tantalum ethoxide into N-methyl-2-pyrrolidone (NMP), stirring to dissolve the tantalum ethoxide to prepare a solution A, and stirring for later use;
2) Dissolving 0.01mol of lithium citrate in NMP, and stirring to form a solution B;
3) 36.5g of graphene was dispersed in NMP and stirred to form solution C;
4) Stirring and mixing the solution A and the solution C uniformly, heating to 60 ℃ for condensation circulation, and stirring to obtain a mixed solution;
5) Dropwise adding the solution B into the mixed solution obtained in the step 4) at a feeding speed of 10r/min through a peristaltic pump, and continuing to perform condensation circulation stirring at 60 ℃ after the dropwise addition is completed to obtain a mixed solution D;
6) Stirring the mixed solution D at 80 ℃ until the solvent volatilizes completely to obtain powder, drying the powder at 80 ℃ for 12h, and grinding for 30min to obtain powder E;
7) And (3) placing the powder E into a tube furnace, calcining at 700 ℃ for 48 hours under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding for 10min to obtain powder F, thus obtaining the graphene/lithium tantalate composite material.
Preparing a graphene/lithium tantalate composite material No. 4 according to the method, and performing ICP elemental analysis and carbon sulfur instrument test analysis, wherein the mass ratio of lithium tantalate to graphene is 1:16. preparing a protective film 4# by the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 193mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 63%.
As is clear from comparison of example 1 and example 4, the capacity retention rate of example 4 was lowered, which is that the addition amount of lithium salt was insufficient to make the lithium salt and tantalum oxide react insufficiently, resulting in impure lithium tantalate synthesized.
Example 5
1) Adding 0.01mol of tantalum oxide into ethanol, stirring to dissolve the tantalum oxide to prepare a solution A, and stirring for later use;
2) Adding 0.0086mol of nickel nitrate into ethanol, stirring to dissolve the nickel nitrate to prepare a solution B, and stirring for later use;
3) Dissolving 0.04mol of lithium acetate in ethanol, and stirring to form a solution C;
4) 48g of graphene is dispersed in ethanol, and solution D is formed after stirring;
5) Stirring and mixing the solution A and the solution D uniformly, heating to 50 ℃ for condensation circulation, and stirring to obtain a mixed solution;
6) Dropwise adding the solution B and the solution C into the mixed solution obtained in the step 5) at a feeding speed of 5r/min through a peristaltic pump, and continuing to perform condensation circulation stirring at 60 ℃ after the dropwise addition is completed to obtain a mixed solution F;
7) Stirring the mixed solution F at 80 ℃ until the solvent is completely volatilized to obtain powder, drying the powder at 80 ℃ for 12h, and grinding for 30min to obtain powder G;
8) And (3) placing the powder G into a tube furnace, calcining for 48 hours at 600 ℃ under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding for 30 minutes to obtain the graphene/lithium tantalate composite material.
The graphene/lithium tantalate composite material 5# prepared by the method is subjected to ICP elemental analysis and carbon sulfur instrument test analysis, and the mass ratio of the element content Ta to Ni=7:3, and the mass ratio of the modified lithium tantalate to the graphene is 1:9. Preparing a protective film 5# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 197 mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 88%.
Example 6
1) Adding 0.02mol of tantalum ethoxide into ethanol, stirring to dissolve the tantalum ethoxide to prepare a solution A, and stirring for later use;
2) Adding 0.0086mol of nickel nitrate into ethanol, stirring to dissolve the nickel nitrate to prepare a solution B, and stirring for later use;
3) Dissolving 0.04mol of lithium acetate in ethanol, and stirring to form a solution C;
4) 48g of graphene is dispersed in ethanol, and solution D is formed after stirring;
5) Stirring and mixing the solution A and the solution D uniformly, heating to 50 ℃ for condensation circulation, and stirring to obtain a mixed solution;
6) Dropwise adding the solution B and the solution C into the mixed solution obtained in the step 5) at a feeding speed of 5r/min through a peristaltic pump, and continuing to perform condensation circulation stirring at 60 ℃ after the dropwise addition is completed to obtain a mixed solution F;
7) Stirring the mixed solution F at 80 ℃ until the solvent is completely volatilized to obtain powder, drying the powder at 80 ℃ for 12h, and grinding for 30min to obtain powder G;
8) And (3) placing the powder G into a tube furnace, calcining for 48 hours at 600 ℃ under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding for 30 minutes to obtain the graphene/lithium tantalate composite material.
Graphene/lithium tantalate composite material No. 6 is prepared according to the method, ICP elemental analysis and carbon sulfur instrument test analysis are carried out on the graphene/lithium tantalate composite material, and the mass ratio of element content Ta is that Ni=7: 3, the mass ratio of the modified lithium tantalate to the graphene is 1:9. Preparing a protective film 6# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 198mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 85%.
Example 7
1) Adding 0.01mol of tantalum oxide into N-methyl-2-pyrrolidone (NMP), stirring to dissolve the tantalum oxide to prepare a solution A, and stirring for later use;
2) Adding 0.0022mol of nickel nitrate into N-methyl-2-pyrrolidone (NMP), stirring to dissolve the nickel nitrate to prepare a solution B, and stirring for later use;
3) 0.03mol of lithium acetate is dissolved in N-methyl-2-pyrrolidone (NMP) and stirred to form a solution C;
4) 4.8g of graphene is dispersed in N-methyl-2-pyrrolidone (NMP), and a solution D is formed after stirring;
5) Stirring and mixing the solution A and the solution D uniformly, heating to 50 ℃ for condensation circulation, and stirring to obtain a mixed solution;
6) Dropwise adding the solution B and the solution C into the mixed solution obtained in the step 5) at a feeding speed of 5r/min through a peristaltic pump, and continuing to perform condensation circulation stirring at 50 ℃ after the dropwise addition is completed to obtain a mixed solution F;
7) Stirring the mixed solution F at 80 ℃ until the solvent is completely volatilized to obtain powder, drying the powder at 80 ℃ for 12h, and grinding for 30min to obtain powder G;
8) And (3) placing the powder G into a tube furnace, calcining for 48 hours at 600 ℃ under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding for 30 minutes to obtain the graphene/lithium tantalate composite material.
Graphene/modified lithium tantalate composite material No. 7 is prepared according to the method, ICP elemental analysis and carbon sulfur instrument test analysis are carried out on the graphene/modified lithium tantalate composite material, and the molar ratio of element content Ta is Ni=9: 1, the mass ratio of lithium tantalate to graphene is 1:1. preparing a protective film 7# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 196 mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 79%.
Example 8
1) Adding 0.02mol of tantalum chloride into isopropanol, stirring to dissolve the tantalum chloride to prepare a solution A, and stirring for later use;
2) Adding 0.02mol of nickel nitrate into isopropanol, stirring to dissolve the nickel nitrate to prepare a solution B, and stirring for later use;
3) Dissolving 0.06mol of lithium acetate in isopropanol, and stirring to form a solution C;
4) 94g of graphene is dispersed in isopropanol and stirred to form a solution D;
5) Stirring and mixing the solution A and the solution D uniformly, heating to 50 ℃ for condensation circulation, and stirring to obtain a mixed solution;
6) Dropwise adding the solution B and the solution C into the mixed solution obtained in the step 5) at a feeding speed of 5r/min through a peristaltic pump, and continuing to perform condensation circulation stirring at 50 ℃ after the dropwise addition is completed to obtain a mixed solution F;
7) Stirring the mixed solution F at 80 ℃ until the solvent is completely volatilized to obtain powder, drying the powder at 80 ℃ for 12h, and grinding for 30min to obtain powder G;
8) And (3) placing the powder G into a tube furnace, calcining for 48 hours at 600 ℃ under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding for 30 minutes to obtain the graphene/lithium tantalate composite material.
Graphene/lithium tantalate composite material 8# is prepared according to the method, ICP elemental analysis and carbon sulfur instrument test analysis are carried out on the graphene/lithium tantalate composite material, and the molar ratio of element content Ta is that Ni=1: 1, the mass ratio of lithium tantalate to graphene is 1:14. Preparing a protective film 8# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 198mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 84%.
Example 9
1) Adding 0.02mol of tantalum ethoxide into ethanol, stirring to dissolve the tantalum ethoxide to prepare a solution A, and stirring for later use;
2) Adding 0.0086mol of strontium nitrate into ethanol, stirring to dissolve the strontium nitrate to prepare a solution B, and stirring for later use;
3) Dissolving 0.04mol of lithium citrate in ethanol, and stirring to form a solution C;
4) Dispersing 38g of graphene in ethanol, and stirring to form a solution D;
5) Stirring and mixing the solution A and the solution D uniformly, heating to 50 ℃ for condensation circulation, and stirring to obtain a mixed solution;
6) Dropwise adding the solution B and the solution C into the mixed solution obtained in the step 5) at a feeding speed of 5r/min through a peristaltic pump, and continuing to perform condensation circulation stirring at 60 ℃ after the dropwise addition is completed to obtain a mixed solution F;
7) Stirring the mixed solution F at 80 ℃ until the solvent is completely volatilized to obtain powder, drying the powder at 80 ℃ for 12h, and grinding for 30min to obtain powder G;
8) And (3) placing the powder G into a tube furnace, calcining for 48 hours at 600 ℃ under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding for 30 minutes to obtain the graphene/lithium tantalate composite material.
Graphene/lithium tantalate composite material 9# is prepared according to the method, ICP elemental analysis and carbon sulfur instrument test analysis are carried out on the graphene/lithium tantalate composite material, ta: sr=7:3, and the mass ratio of lithium tantalate to graphene is 1:6.5. preparing a protective film 9# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 200mAh/g, and the cycle was carried out at a rate of 0.1C for 200 weeks, with a capacity retention of 82%.
Example 10
The preparation method is the same as in example 5, and the metal salt uses tantalum oxide and silver nitrate to prepare a graphene/lithium tantalate composite material 10#, and ICP elemental analysis and carbon sulfur instrument test analysis are carried out on the composite material, wherein Ta is Ag=7:3, and the mass ratio of the modified lithium tantalate to the graphene is 1:9. Preparing a protective film 10# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 198mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 85%.
Example 11
The preparation method is the same as in example 5, the metal salt is tantalum oxide and manganese nitrate, the graphene/lithium tantalate composite material 11# is prepared, ICP elemental analysis and carbon sulfur instrument test analysis are carried out on the composite material, ta: mn=7:3, and the mass ratio of the modified lithium tantalate to the graphene is 1:9. Preparing a protective film 11# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 195mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 82%.
Example 12
The preparation method is the same as in example 5, and the metal salt uses tantalum oxide and zinc nitrate to prepare a graphene/lithium tantalate composite material 12# which is subjected to ICP elemental analysis and carbon sulfur instrument test analysis, wherein Ta: zn=7:3, and the mass ratio of the modified lithium tantalate to the graphene is 1:9. Preparing a protective film 12# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 197 mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 84%.
Example 13
The preparation method is the same as in example 5, and the metal salt uses tantalum oxide, nickel nitrate and zinc nitrate to prepare a graphene/lithium tantalate composite material 13# which is subjected to ICP elemental analysis and carbon sulfur instrument test analysis, wherein Ta: ni: zn=6.5: 2.5:1, and the mass ratio of the modified lithium tantalate to the graphene is 1:9. Preparing a protective film 13# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 198mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 92%.
Example 14
The preparation method is the same as in example 5, and the metal salt uses tantalum oxide and nickel nitrate to prepare a graphene/lithium tantalate composite material 14# which is subjected to ICP elemental analysis and carbon sulfur instrument test analysis, wherein Ta is Ni=7:3, and the mass ratio of the modified lithium tantalate to the graphene is 1:49. Preparing a protective film 14# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 197 mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 79%.
Example 15
The preparation method is the same as in example 5, and the metal salt uses tantalum oxide and nickel oxide to prepare a graphene/lithium tantalate composite material 15# which is subjected to ICP elemental analysis and carbon sulfur instrument test analysis, wherein Ta is Ni=7:3, and the mass ratio of the modified lithium tantalate to the graphene is 1:9. Preparing a protective film 15# according to the method, assembling the protective film into a CR2032 button lithium ion battery, and performing charge and discharge test: the discharge capacity at 0.1C was 196 mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 81%.
Comparative example 1
Weighing 5g of natural graphite powder, putting the powder into 50ml of ethanol solution, carrying out ultrasonic treatment for 1h, and stirring for 1h; heating the graphite solution which is uniformly dispersed to 60 ℃ for condensation circulation, and continuously stirring for 1h to obtain a mixed solution; after the reaction is finished, naturally cooling to room temperature, respectively cleaning with deionized water and ethanol for 4 times, and then drying in a drying oven for 12 hours at 50 ℃. And (3) placing the dried powder into a tube furnace, heating to 600 ℃ at a speed of 5 ℃/min, and keeping the temperature for 4 hours. Naturally cooling to room temperature to obtain the negative electrode material, and placing the negative electrode material in a vacuum drying oven for standby.
Mixing graphene with PVDF binder solution and Surp-P conductive agent to obtain graphene mixed slurry; coating the mixed slurry on a Mylar film to obtain a graphene film, preparing a comparative graphene protective film, assembling the comparative graphene protective film into a CR2032 button lithium ion battery, and performing charge and discharge tests: the discharge capacity at 0.1C was 195mAh/g, and the cycle was continued at a rate of 0.1C for 200 weeks, with a capacity retention of 45%.
As can be seen from fig. 1, the comparative standard card shows that the graphene/lithium tantalate composite material prepared in example 5 has no impurity phase compared with comparative example 1. As can be seen from fig. 2, the graphene/lithium tantalate composite material prepared in example 5 has a better morphology, which is conducive to uniform deposition of lithium metal. As can be seen from fig. 3, the film material prepared from the graphene/lithium tantalate composite material of example 5 has smaller polarization and longer service life, and further illustrates that the film material prepared from the graphene/lithium tantalate composite material can improve the cycle stability of the lithium metal battery as a lithium metal protection layer.
As can be seen from examples 1 to 4 and comparative example 1, the lithium tantalates of examples 1 to 4 provide a large number of active sites for lithium metal transformation and deposition, thereby further reducing the occurrence of side reactions of lithium metal during charge and discharge and improving the stability and rate performance of the electrode.
As can be seen from fig. 4, the film material prepared from the modified lithium tantalate/graphene composite material further doped with the transition metal element of example 12 has better cycle performance than the graphene protective film of comparative example 1 and the lithium tantalate/graphene protective film of example 1. This is because the modified lithium tantalate is used as a carrier to carry the functional metal to the surface of the lithium negative electrode, and is released in situ during the reduction process to form lithium tantalate and the functional metal, as shown in fig. 5, and various modification strategies are simultaneously realized. Wherein lithium tantalate is discharged to 0V (vs. Li) + Li) is still reversible, and lithium tantalate lithiate can significantly improve the cycle performance of lithium metal batteries. The substituted metal ions will be reduced to metal and act alone, thus selecting as the substituted ions metal ions that contribute to the improved cycle life of the metallic lithium. According to the current research results, the lithium metal is improvedFunctional metals of deposition behavior include two classes, one being capable of forming dense SEI films with electrolytes, such as Ni, mn, ag, etc., helping to protect metallic lithium from reaction with electrolytes; the other class can be alloyed with lithium metals, such as Zn, sr, etc., reducing the activity of the metals. And the modified lithium tantalate is deposited on the surface of the graphene, so that the dispersibility of the material is improved.
Although the present invention has been described in detail by way of preferred embodiments with reference to the accompanying drawings, the present invention is not limited thereto. Various equivalent modifications and substitutions may be made in the embodiments of the present invention by those skilled in the art without departing from the spirit and scope of the present invention, and it is intended that all such modifications and substitutions be within the scope of the present invention/be within the scope of the present invention as defined by the appended claims. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (10)
1. The modified lithium tantalate modified graphene nanomaterial is characterized in that the chemical formula of the modified lithium tantalate is LiM x Ta 1- x O 3 M is one or more transition metal elements, and x is more than or equal to 0 and less than or equal to 0.5;
the preparation method of the modified lithium tantalate modified graphene nanomaterial comprises the following steps of:
1) Adding a tantalum source into a volatile solvent, stirring to dissolve the tantalum source, preparing a solution, and stirring for later use;
2) Dissolving lithium salt in a volatile solvent, and stirring to form a solution;
3) Dispersing graphene in a volatile solvent, and stirring to form a solution;
4) Stirring and mixing the solution in the step 1) and the solution in the step 3) uniformly, heating, condensing and circulating, and stirring to obtain a mixed solution;
5) Dropwise adding the solution obtained in the step 2) into the mixed solution obtained in the step 4), and continuously condensing, circulating and stirring after the dropwise adding is completed to obtain a mixed solution;
6) Stirring and heating the mixed solution obtained in the step 5) until the volatile solvent is completely volatilized to obtain powder, and drying and grinding the powder to obtain powder;
7) Calcining the powder obtained in the step 6) under the protection of argon or nitrogen, cooling to room temperature, taking out the powder, and grinding to obtain the powder, thus obtaining the modified lithium tantalate modified graphene nanomaterial.
2. The modified lithium tantalate modified graphene nanomaterial of claim 1, wherein the volatile solvent is ethanol, methanol, isopropanol, N-methyl-2-pyrrolidone.
3. The modified lithium tantalate modified graphene nanomaterial of claim 1, wherein a metal M compound is added to a volatile solvent to prepare a solution, and is added dropwise to the mixed solution obtained in step 4) together with the solution B; wherein the metal M compound is one or more of sulfate, nitrate, chloride, acetate and oxide of M, and M is one or more transition metal elements; the tantalum source is tantalum oxide, tantalum chloride or tantalum ethoxide.
4. The modified lithium tantalate modified graphene nanomaterial of claim 1 or 3, wherein M is Ni 2+ 、Mn 2+ 、Ag + 、Zn 2+ And Sr 3+ One or more of the following.
5. The modified lithium tantalate modified graphene nanomaterial of claim 3, wherein the molar ratio of the metal M salt to the tantalum source is less than or equal to 1.
6. The modified lithium tantalate modified graphene nanomaterial of claim 1, wherein in step 2) the lithium salt is one or more of lithium hydroxide, lithium acetate, and lithium citrate.
7. The modified lithium tantalate modified graphene nanomaterial of claim 1, wherein in step 2), the molar ratio of lithium salt to tantalum element is 1-3:1.
8. the modified lithium tantalate modified graphene nanomaterial of claim 1, wherein in step 7), the mass ratio of product modified lithium tantalate to graphene is 1:1-49.
9. A film comprising the modified lithium tantalate-modified graphene nanomaterial of claim 1, consisting of a binder, a conductive carbon material, and the modified lithium tantalate-modified graphene nanomaterial.
10. Use of a film according to claim 9 as a lithium electrode protection component in a lithium battery.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202211444560.7A CN115676888B (en) | 2022-11-18 | 2022-11-18 | Modified lithium tantalate modified graphene nanomaterial and preparation method and application thereof |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202211444560.7A CN115676888B (en) | 2022-11-18 | 2022-11-18 | Modified lithium tantalate modified graphene nanomaterial and preparation method and application thereof |
Publications (2)
Publication Number | Publication Date |
---|---|
CN115676888A CN115676888A (en) | 2023-02-03 |
CN115676888B true CN115676888B (en) | 2024-01-02 |
Family
ID=85053685
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202211444560.7A Active CN115676888B (en) | 2022-11-18 | 2022-11-18 | Modified lithium tantalate modified graphene nanomaterial and preparation method and application thereof |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN115676888B (en) |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110212169A (en) * | 2019-05-05 | 2019-09-06 | 浙江大学 | A kind of lithium-sulfur cell self-supporting positive electrode and preparation method thereof |
CN110835781A (en) * | 2018-08-16 | 2020-02-25 | 江南石墨烯研究院 | Blackening method of lithium niobate or lithium tantalate wafer |
CN113257991A (en) * | 2021-06-25 | 2021-08-13 | 之江实验室 | 003-type flexible piezoelectric composite material, flexible multilayer actuator and preparation method |
-
2022
- 2022-11-18 CN CN202211444560.7A patent/CN115676888B/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110835781A (en) * | 2018-08-16 | 2020-02-25 | 江南石墨烯研究院 | Blackening method of lithium niobate or lithium tantalate wafer |
CN110212169A (en) * | 2019-05-05 | 2019-09-06 | 浙江大学 | A kind of lithium-sulfur cell self-supporting positive electrode and preparation method thereof |
CN113257991A (en) * | 2021-06-25 | 2021-08-13 | 之江实验室 | 003-type flexible piezoelectric composite material, flexible multilayer actuator and preparation method |
Non-Patent Citations (2)
Title |
---|
Effects of MnO2 addition on the microstructure and dielectric properties of LiTaO3 ceramics;Wanwan Yang等;《Vacuum》;109130 * |
Growth and holographic data storage properties of near-stoichiometric LiTaO3 crystals doped with Mn;Tao Zhang等;《Materials Chemistry and Physics》;257-260 * |
Also Published As
Publication number | Publication date |
---|---|
CN115676888A (en) | 2023-02-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2020134781A1 (en) | Positive electrode material with high compacted density and electrochemical energy storage device | |
CN112313819B (en) | Method of manufacturing negative electrode for lithium secondary battery and method of manufacturing lithium secondary battery | |
US11380881B2 (en) | Anode material of lithium ion battery and non-aqueous electrolyte battery | |
KR101264332B1 (en) | Cathode active material and lithium battery using the same | |
KR101500545B1 (en) | Negative electrode and secondary cell | |
CN109616614B (en) | Negative electrode sheet, and electrochemical device and electronic device using same | |
KR20090066019A (en) | Anode comprising surface treated anode active material and lithium battery using the same | |
JP2010080105A (en) | Method of manufacturing nonaqueous electrolyte secondary battery | |
CN108777294B (en) | Carbon-supported porous spherical MoN composed of nanosheets and application of carbon-supported porous spherical MoN as negative electrode material in lithium battery | |
CN113381005B (en) | Single-crystal ternary cathode material, continuous preparation method and device and application | |
US20210159485A1 (en) | Surface-fluorinated silicon-containing electrodes | |
KR101646994B1 (en) | Positive active material for rechargeable lithium battery, method for manufacturing the same, and rechargeable lithium battery including the same | |
KR101375326B1 (en) | Composite anode active material, method of preparing the same, anode and lithium battery containing the material | |
CN109411706B (en) | Modified working electrode and preparation method thereof | |
JP2003308880A (en) | Method of manufacturing lithium secondary battery | |
JP2002042812A (en) | Positive electrode active material for lithium secondary battery and lithium secondary battery using the same | |
CN109216692B (en) | Modified ternary cathode material, preparation method thereof and lithium ion battery | |
JP2000156224A (en) | Nonaqueous electrolyte battery | |
CN115676888B (en) | Modified lithium tantalate modified graphene nanomaterial and preparation method and application thereof | |
CN115411253A (en) | Carbon-coated one-dimensional ferrous fluoride anode material and preparation method and application thereof | |
CN111900375B (en) | Preparation method of long-life negative electrode material for power energy storage and application of long-life negative electrode material in lithium ion battery | |
JP2009104974A (en) | Cathode material for nonaqueous secondary battery, its manufacturing method, and nonaqueous secondary battery using it | |
KR20070059829A (en) | Novel anode active material, producing method thereof, and lithium secondary battery comprising the same | |
KR101490406B1 (en) | Positive electrode active material coated with fluorine compounds for lithium secondary battery and preparation method thereof | |
JP4561040B2 (en) | Nonaqueous electrolyte secondary battery |
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 |