CN114597368B - Lithium-rich manganese-based layered material with surface sulfur doped and lithium sulfate protective layer - Google Patents
Lithium-rich manganese-based layered material with surface sulfur doped and lithium sulfate protective layer Download PDFInfo
- Publication number
- CN114597368B CN114597368B CN202210253380.4A CN202210253380A CN114597368B CN 114597368 B CN114597368 B CN 114597368B CN 202210253380 A CN202210253380 A CN 202210253380A CN 114597368 B CN114597368 B CN 114597368B
- Authority
- CN
- China
- Prior art keywords
- lithium
- rich manganese
- based layered
- layered material
- protective layer
- 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
- 239000000463 material Substances 0.000 title claims abstract description 121
- 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
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 title claims abstract description 59
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 title claims abstract description 53
- 229910052748 manganese Inorganic materials 0.000 title claims abstract description 53
- 239000011572 manganese Substances 0.000 title claims abstract description 53
- 239000011593 sulfur Substances 0.000 title claims abstract description 36
- 229910052717 sulfur Inorganic materials 0.000 title claims abstract description 36
- INHCSSUBVCNVSK-UHFFFAOYSA-L lithium sulfate Inorganic materials [Li+].[Li+].[O-]S([O-])(=O)=O INHCSSUBVCNVSK-UHFFFAOYSA-L 0.000 title claims abstract description 27
- RBTVSNLYYIMMKS-UHFFFAOYSA-N tert-butyl 3-aminoazetidine-1-carboxylate;hydrochloride Chemical compound Cl.CC(C)(C)OC(=O)N1CC(N)C1 RBTVSNLYYIMMKS-UHFFFAOYSA-N 0.000 title claims abstract description 27
- 239000011241 protective layer Substances 0.000 title claims abstract description 24
- 239000001301 oxygen Substances 0.000 claims abstract description 34
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 34
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 33
- 238000001354 calcination Methods 0.000 claims abstract description 18
- 239000012298 atmosphere Substances 0.000 claims abstract description 11
- 230000000630 rising effect Effects 0.000 claims abstract description 6
- 238000010438 heat treatment Methods 0.000 claims description 24
- 239000000843 powder Substances 0.000 claims description 19
- 239000013067 intermediate product Substances 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 15
- 239000007774 positive electrode material Substances 0.000 claims description 12
- 238000001291 vacuum drying Methods 0.000 claims description 12
- 229910008555 Li1.2Mn0.6Ni0.2O2 Inorganic materials 0.000 claims description 10
- 238000000227 grinding Methods 0.000 claims description 9
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 8
- 238000001704 evaporation Methods 0.000 claims description 8
- 238000003756 stirring Methods 0.000 claims description 8
- 238000001132 ultrasonic dispersion Methods 0.000 claims description 8
- 238000001035 drying Methods 0.000 claims description 4
- 239000002344 surface layer Substances 0.000 abstract description 10
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 abstract description 8
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 abstract description 5
- 229910001416 lithium ion Inorganic materials 0.000 abstract description 4
- 239000011248 coating agent Substances 0.000 abstract description 3
- 238000000576 coating method Methods 0.000 abstract description 3
- 239000003513 alkali Substances 0.000 abstract description 2
- 238000011065 in-situ storage Methods 0.000 abstract description 2
- 239000011159 matrix material Substances 0.000 abstract 4
- 239000000203 mixture Substances 0.000 abstract 1
- 238000012360 testing method Methods 0.000 description 18
- 239000011149 active material Substances 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- 238000002441 X-ray diffraction Methods 0.000 description 7
- 238000004833 X-ray photoelectron spectroscopy Methods 0.000 description 7
- 230000014759 maintenance of location Effects 0.000 description 7
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 229910013290 LiNiO 2 Inorganic materials 0.000 description 5
- 229910052723 transition metal Inorganic materials 0.000 description 4
- 150000003624 transition metals Chemical class 0.000 description 4
- 230000002427 irreversible effect Effects 0.000 description 3
- GLNWILHOFOBOFD-UHFFFAOYSA-N lithium sulfide Chemical compound [Li+].[Li+].[S-2] GLNWILHOFOBOFD-UHFFFAOYSA-N 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 238000001878 scanning electron micrograph Methods 0.000 description 3
- -1 sulfur anion Chemical class 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 description 2
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 2
- 239000002033 PVDF binder Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000003792 electrolyte Substances 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000012266 salt solution Substances 0.000 description 2
- 238000007086 side reaction Methods 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- 229910013872 LiPF Inorganic materials 0.000 description 1
- 101150058243 Lipf gene Proteins 0.000 description 1
- MQRWBMAEBQOWAF-UHFFFAOYSA-N acetic acid;nickel Chemical compound [Ni].CC(O)=O.CC(O)=O MQRWBMAEBQOWAF-UHFFFAOYSA-N 0.000 description 1
- 239000006230 acetylene black Substances 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
- 235000011114 ammonium hydroxide Nutrition 0.000 description 1
- 239000010405 anode material Substances 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000010406 cathode material Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 239000002019 doping agent Substances 0.000 description 1
- 239000007772 electrode material Substances 0.000 description 1
- 238000004993 emission spectroscopy Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 1
- 238000009616 inductively coupled plasma Methods 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- XIXADJRWDQXREU-UHFFFAOYSA-M lithium acetate Chemical compound [Li+].CC([O-])=O XIXADJRWDQXREU-UHFFFAOYSA-M 0.000 description 1
- 229940071257 lithium acetate Drugs 0.000 description 1
- 229940071125 manganese acetate Drugs 0.000 description 1
- UOGMEBQRZBEZQT-UHFFFAOYSA-L manganese(2+);diacetate Chemical compound [Mn+2].CC([O-])=O.CC([O-])=O UOGMEBQRZBEZQT-UHFFFAOYSA-L 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000002715 modification method Methods 0.000 description 1
- 229940078494 nickel acetate Drugs 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 238000011112 process operation Methods 0.000 description 1
- 238000006479 redox reaction Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000004611 spectroscopical analysis Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 125000004434 sulfur atom Chemical group 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 229910001428 transition metal ion Inorganic materials 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/366—Composites as layered products
-
- 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
- H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention relates to a lithium-rich manganese-based layered material doped with surface sulfur and provided with a lithium sulfate protective layer, belonging to the technical field of lithium ion batteries. The material takes a lithium-rich manganese-based layered material as a matrix, sulfur is doped on the surface of the matrix and is coated with lithium sulfate, the mixture is calcined in an oxygen atmosphere after elemental sulfur is mixed with the lithium-rich manganese-based layered material, and sulfur enters the matrix and is doped on the surface layer of the matrix on one hand and reacts with oxygen to generate sulfur dioxide on the other hand by controlling the flow rate of oxygen, the temperature rising rate and the calcining temperature and time, and the sulfur dioxide reacts with residual alkali on the surface of the lithium-rich manganese-based layered material to generate a lithium sulfate coating in situ. The material has good electrochemical properties.
Description
Technical Field
The invention relates to a lithium-rich manganese-based layered material doped with surface sulfur and provided with a lithium sulfate protective layer, belonging to the technical field of lithium ion batteries.
Background
In lithium ion batteries, lithium-rich manganese-based layered materials have emerged as a research hotspot for positive electrode materials due to their ultra-high specific discharge capacity (> 250 mAh/g). However, because the lithium-rich manganese-based layered material has more serious irreversible oxygen release, the structural transformation and the attenuation of a discharge platform can be caused, and therefore, in actual use, the material needs to be modified, so that the oxygen loss and the occurrence of phase change are reduced.
The modification method which is more commonly used at present is to dope the elements, and S element is a common doping agent due to the similar characteristics of the S element and O. In the preparation method of the sulfur anion doped lithium-rich cathode material disclosed in Chinese patent application CN106229502A, lithium sulfide is added in the precursor lithium mixing stage, and sulfur doping is realized through the subsequent 900 ℃ high temperature. However, in the method, lithium sulfide is easy to absorb water in the air and hydrolyze to release highly toxic hydrogen sulfide gas, so that the environment and human health are endangered, the melting point of the lithium sulfide is above 900 ℃, the doping temperature is too high, and the energy cost is increased; meanwhile, sulfur in the final material is doped in bulk phase, so that the surface side reaction is less inhibited, and partial capacity loss is caused by substitution of the bulk phase doping relative to oxygen. In the modified lithium ion battery anode material and the preparation method thereof disclosed in Chinese patent application CN111697208A, elemental sulfur or sulfur-containing materials are utilized to form sulfur vapor by heating, and the materials are treated. The concentration of sulfur vapor is large, the process operation is too complex, and the requirement on equipment is high; the capacity and stability of the final material remain to be further improved.
Disclosure of Invention
In view of the above, the present invention aims to provide a lithium-rich manganese-based layered material with a surface sulfur doped and a lithium sulfate protective layer.
In order to achieve the above purpose, the technical scheme of the invention is as follows:
a lithium-rich manganese-based layered material with a surface sulfur-doped and lithium sulfate protective layer, the material being prepared by the method comprising the steps of:
(1) Grinding and dispersing elemental sulfur powder in absolute ethyl alcohol uniformly, adding a lithium-rich manganese-based layered material, carrying out ultrasonic dispersion uniformly, heating, stirring, evaporating to dryness, and carrying out vacuum drying to obtain an intermediate product; wherein, the mol ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.01:1-0.1:1;
(2) Calcining the intermediate product for 4-8 hours at 200-300 ℃ under the oxygen atmosphere in a tube furnace at the oxygen flow rate of 60-200 mL/min and the heating rate of 6-12 ℃/min to obtain the lithium-rich manganese-based layered material with the surface doped with sulfur and the lithium sulfate protective layer.
In step (1):
preferably, the lithium-rich manganese-based layered material is Li 1.2 Mn 0.6 Ni 0.2 O 2 。
Preferably, the molar ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.03:1-0.06:1.
Preferably, the vacuum drying temperature is 60-120 ℃ and the drying time is 10-12 h.
In the step (2):
preferably, the temperature rising rate during calcination is 8-10 ℃/min.
Preferably, the oxygen flow rate is 80mL/min to 150mL/min.
Advantageous effects
The invention provides a lithium-rich manganese-based layered material with a surface sulfur doped and a lithium sulfate protective layer, wherein the lithium sulfate protective layer on the surface of the material can improve the stability of an electrode material, can relieve side reactions of an electrode and electrolyte, improve the stability of an interface, can increase the ion transmission of the interface and is beneficial to improving the rate capability; s doped on the surface is favorable for lithium ion extraction, improves the rate performance and the discharge capacity, and meanwhile, the introduction of S can also increase O 2 The released energy barrier relieves irreversible oxygen release in circulation and improves the circulation stability; dopingThe S atoms that enter the lattice can also act as an anchor for the cladding layer.
The invention provides a lithium-rich manganese-based layered material with a surface sulfur doped and a lithium sulfate protective layer, which is prepared by mixing elemental sulfur with the lithium-rich manganese-based layered material, calcining the material in an oxygen atmosphere, and controlling the flow rate of oxygen, the heating rate, the calcining temperature and the calcining time, wherein on one hand, sulfur enters a substrate and is doped on the surface layer of the substrate, on the other hand, sulfur also reacts with oxygen to generate sulfur dioxide, and the sulfur dioxide reacts with residual alkali on the surface of the lithium-rich manganese-based layered material to generate a lithium sulfate coating in situ; the proper oxygen flow rate and higher temperature rising rate can reduce sulfur loss, and the method can greatly improve the electrochemical performance of the material by only needing trace sulfur.
Drawings
FIG. 1 is an X-ray diffraction (XRD) pattern of the materials described in examples 1-4.
Fig. 2 is a Scanning Electron Microscope (SEM) image of the material described in example 1.
Fig. 3 is an SEM image of the material described in example 2.
Fig. 4 is an SEM image of the material described in example 3.
Fig. 5 is an SEM image of the material described in example 4.
Fig. 6 is a discharge capacity graph of the assembled batteries of example 1 and comparative example 1 at 30C for 50 weeks at 1C.
Fig. 7 is an alternating current impedance (EIS) diagram of the assembled batteries of example 2 and comparative example 1.
Fig. 8 is a first week capacity differential curve at 0.1C magnification of the assembled batteries of example 3 and comparative example 1.
Fig. 9 is an X-ray photoelectron spectroscopy (XPS) diagram of the material described in example 4.
Detailed Description
The present invention will be described in further detail with reference to specific examples.
In the following examples:
(1) XRD test: the instrument used was Rigaku Ultima IV-185, japan.
(2) SEM testing, spectroscopy (EDS): the instrument used was FEI Quanta, netherlands.
(3) XPS test: the instrument used was ULVAC-PHI, japan.
(4) Inductively coupled plasma emission spectroscopy (ICP-OES) test: the instrument used was agilenticpoe 730, usa.
(5) And (3) battery assembly: mixing the active material with acetylene black and polyvinylidene fluoride (PVDF) according to the mass ratio of 8:1:1, adding N-methyl pyrrolidone (NMP), grinding into slurry, coating the slurry on aluminum foil by using a scraper, drying, and cutting into positive plates; then, the CR2025 button half-cell is assembled in an argon glove box (water is less than 0.01ppm, oxygen is less than 0.01 ppm), wherein the positive electrode is the positive electrode plate, the counter electrode is a lithium plate, the diaphragm is Celgard 2500, the electrolyte is prepared from dimethyl carbonate, diethyl carbonate and ethyl carbonate with the volume ratio of 1:1:1 as solvents, and 1mol/L of LiPF is adopted 6 Is a solution made of solute.
(6) Cell performance test: the LAND CT 2001A tester is adopted and purchased from blue electric electronic Co., ltd; at 30 ℃, the charge and discharge cycle is carried out for 2 weeks in a voltage interval of 2.0V-4.8V at 0.1C (1 C=250 mA/g), and then the charge and discharge cycle is continued for 50 weeks in a voltage interval of 2.0V-4.6V at 1C.
(7) Alternating current impedance test: the CHI604D electrochemical workstation was used and purchased from Shanghai Chen Hua instruments Inc.
Example 1
(1) Grinding and dispersing elemental sulfur powder in absolute ethyl alcohol uniformly, and then adding lithium-rich manganese-based layered material Li 1.2 Mn 0.6 Ni 0.2 O 2 After uniform ultrasonic dispersion, heating to 70 ℃, stirring, evaporating to dryness, and vacuum drying at 80 ℃ for 12 hours to obtain an intermediate product; wherein, the mol ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.03:1;
(2) And calcining the intermediate product at 270 ℃ for 8 hours under the oxygen atmosphere in the tubular furnace at the oxygen flow rate of 80mL/min, and heating at the heating rate of 10 ℃/min to obtain the lithium-rich manganese-based layered material with the surface doped with sulfur and the lithium sulfate protective layer.
XRD of the materialThe test results are shown in FIG. 1, and the characteristic peak positions of the material and LiNiO 2 And Li (lithium) 2 MnO 3 The characteristic peaks of the (C) are consistent, no obvious miscellaneous peaks exist, and the (C) has a better lamellar structure.
The SEM test result of the material is shown in figure 2, the average particle size of the material is 100 nm-200 nm, and particles are attached to the surface of the material.
EDS results of the material show that S elements are distributed on the surface layer of the material. The ICP-OES result of the material shows that the content of S element in the material is 0.0478wt%.
XPS test results of the material show that the peak at 160eV-164eV exists a bond between S-TM (TM: transition metal), and SO exists between 167eV-170eV 4 2- The method comprises the steps of carrying out a first treatment on the surface of the As can be seen from the EDS result, the surface layer of the material is doped with sulfur and coated with Li 2 SO 4 。
As shown in fig. 6, with the material as an active material, the assembled battery had a specific capacity of 225.4mAh/g at the first week during a 1C rate cycle at 30 ℃, a capacity of 203mAh/g after 50 weeks of the cycle, and a capacity retention rate of 90.06%.
Example 2
(1) Grinding and dispersing elemental sulfur powder in absolute ethyl alcohol uniformly, and then adding lithium-rich manganese-based layered material Li 1.2 Mn 0.6 Ni 0.2 O 2 After uniform ultrasonic dispersion, heating to 70 ℃, stirring, evaporating to dryness, and vacuum drying at 80 ℃ for 12 hours to obtain an intermediate product; wherein, the mol ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.03:1;
(2) And calcining the intermediate product at 270 ℃ for 6 hours under the oxygen atmosphere in the tubular furnace at the oxygen flow rate of 100mL/min, and heating at the temperature rate of 7 ℃/min to obtain the lithium-rich manganese-based layered material with the surface doped with sulfur and the lithium sulfate protective layer.
The XRD test result of the material is shown in figure 1, and the characteristic peak position of the material and LiNiO 2 And Li (lithium) 2 MnO 3 The characteristic peaks of the (C) are consistent, no obvious miscellaneous peaks exist, and the (C) has a better lamellar structure.
The SEM test result of the material is shown in figure 3, the average particle size of the material is 100 nm-200 nm, and particles are attached to the surface of the material.
EDS results of the material show that S elements are distributed on the surface layer of the material. The ICP-OES result of the material shows that the content of S element in the material is 0.0382wt%.
XPS test results of the material show that the peak at 160eV-164eV exists a bond between S-TM (TM is transition metal), and SO exists between 167eV-170eV 4 2- The method comprises the steps of carrying out a first treatment on the surface of the As can be seen from the EDS result, the surface layer of the material is doped with sulfur and coated with Li 2 SO 4 。
The material is used as an active material, the initial cycle specific capacity of the assembled battery is 221.9mAh/g in the 1C rate circulation process at 30 ℃, the capacity after 50 weeks circulation is 200.4mAh/g, and the capacity retention rate is 90.31%.
As shown in fig. 7, the EIS result of the assembled battery shows that the material of the present example has a lower interfacial charge transfer resistance compared to comparative example 1; the material of this example is shown to facilitate interfacial ion transfer, thereby reducing impedance.
Example 3
(1) Grinding and dispersing elemental sulfur powder in absolute ethyl alcohol uniformly, and then adding lithium-rich manganese-based layered material Li 1.2 Mn 0.6 Ni 0.2 O 2 After uniform ultrasonic dispersion, heating to 70 ℃, stirring, evaporating to dryness, and vacuum drying at 80 ℃ for 12 hours to obtain an intermediate product; wherein, the mol ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.03:1;
(2) And calcining the intermediate product at 270 ℃ for 8 hours under the oxygen atmosphere in the tubular furnace at the oxygen flow rate of 80mL/min, and heating at the heating rate of 10 ℃/min to obtain the lithium-rich manganese-based layered material with the surface doped with sulfur and the lithium sulfate protective layer.
The XRD test result of the material is shown in figure 1, and the characteristic peak position of the material and LiNiO 2 And Li (lithium) 2 MnO 3 The characteristic peaks of the (C) are consistent, no obvious miscellaneous peaks exist, and the (C) has a better lamellar structure.
The SEM test result of the material is shown in figure 4, the average particle size of the material is 100 nm-150 nm, and particles are attached to the surface of the material.
EDS results of the material show that S elements are distributed on the surface layer of the material. The ICP-OES result of the material shows that the content of S element in the material is 0.0412wt%.
XPS test results of the material show that the peak at 160eV-164eV exists a bond between S-TM (TM: transition metal), and SO exists between 167eV-170eV 4 2- The method comprises the steps of carrying out a first treatment on the surface of the As can be seen from the EDS result, the surface layer of the material is doped with sulfur and coated with Li 2 SO 4 。
The material is used as an active material, the initial cycle specific capacity of the assembled battery is 212.4mAh/g in the 1C rate circulation process at 30 ℃, the capacity after 50 weeks circulation is 206.7mAh/g, and the capacity retention rate is 97.31%.
The first week capacity differential curve of the assembled battery at 0.1C rate is shown in fig. 8, and the material redox peak intensity in this example has a significant effect compared to comparative example 1. In the dQ/dV plot, the curve shape is substantially consistent indicating that the redox reactions occurring for the materials are the same. The Jiang Yanghua peak at a voltage of about 4.5V is considered to be the irreversible release of oxygen anions, and as can be seen from the figure, the peak position of the treated material is slightly biased towards the high voltage direction, and the peak strength is obviously reduced, which indicates that the material in the embodiment has obvious alleviation on oxygen release, improves the reaction potential and reduces the reaction quantity, and is beneficial to the circulation stability of the material.
Example 4
(1) Grinding and dispersing elemental sulfur powder in absolute ethyl alcohol uniformly, and then adding lithium-rich manganese-based layered material Li 1.2 Mn 0.6 Ni 0.2 O 2 After uniform ultrasonic dispersion, heating to 70 ℃, stirring, evaporating to dryness, and vacuum drying at 80 ℃ for 12 hours to obtain an intermediate product; wherein, the mol ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.06:1;
(2) And calcining the intermediate product at 270 ℃ for 6 hours under the oxygen atmosphere in the tubular furnace at the oxygen flow rate of 100mL/min, and heating at the temperature rate of 7 ℃/min to obtain the lithium-rich manganese-based layered material with the surface doped with sulfur and the lithium sulfate protective layer.
The XRD test result of the material is shown in figure 1, and the characteristic peak position of the material and LiNiO 2 And Li (lithium) 2 MnO 3 The characteristic peaks of the (C) are consistent, no obvious miscellaneous peaks exist, and the (C) has a better lamellar structure.
The SEM test result of the material is shown in FIG. 5, the average particle size of the material is 100 nm-200 nm, and particles are attached to the surface of the material.
EDS results of the material show that S elements are distributed on the surface layer of the material. The ICP-OES result of the material shows that the content of S element in the material is 0.0747wt%.
As shown in FIG. 9, the XPS test results of the material show that the peak at 160eV-164eV has bonds between S-TM (TM: transition metal) and SO between 167eV-170eV 4 2- The method comprises the steps of carrying out a first treatment on the surface of the As can be seen from the EDS result, the surface layer of the material is doped with sulfur and coated with Li 2 SO 4 。
The material is used as an active material, the initial cycle specific capacity of the assembled battery is 227.7mAh/g in the 1C rate circulation process at 30 ℃, the capacity after 50 weeks circulation is 205.4mAh/g, and the capacity retention rate is 90.22%.
Comparative example 1
Weighing lithium acetate, manganese acetate and nickel acetate according to the molar ratio of 1.2:0.6:0.2, and adding distilled water for dissolution to obtain a mixed salt solution; then dropwise adding a citric acid solution into the mixed salt solution, and then regulating the pH value to 7.8 by using ammonia water to obtain a mixed solution; heating to gel state at 80 ℃, vacuum drying at 80 ℃ for 40 hours, placing in a muffle furnace under oxygen atmosphere, heating to 500 ℃ for calcination for 6 hours, heating to 800 ℃ for calcination for 14 hours, and obtaining the lithium-rich manganese-based layered material Li 1.2 Mn 0.6 Ni 0.2 O 2 The method comprises the steps of carrying out a first treatment on the surface of the Wherein, the mol ratio of the citric acid to the transition metal ions is 1:1; the temperature rising rate during calcination is 5 ℃/min.
XRD test results of the material show that the characteristic peak position of the material is similar to LiNiO 2 And Li (lithium) 2 MnO 3 The characteristic peaks of the (C) are consistent, no obvious miscellaneous peaks exist, and the (C) has a better lamellar structure.
As shown in fig. 6, the assembled battery has a specific capacity of 283.9mAh/g at 30 ℃ and 0.1C for the first week discharge, using the material as an active material. In the 1C rate circulation process, the first week specific capacity is 175.4mAh/g, the capacity after 50 weeks circulation is 126.2mAh/g, and the retention rate is 71.95%.
Comparative example 2
(1) Grinding and dispersing elemental sulfur powder in absolute ethyl alcohol uniformly, and then adding lithium-rich manganese-based layered material Li 1.2 Mn 0.6 Ni 0.2 O 2 After uniform ultrasonic dispersion, heating to 70 ℃, stirring, evaporating to dryness, and vacuum drying at 80 ℃ for 12 hours to obtain an intermediate product; wherein, the mol ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.2:1;
(2) And calcining the intermediate product at 270 ℃ for 6 hours under the oxygen atmosphere in the tubular furnace at the oxygen flow rate of 100mL/min, and heating at the temperature rate of 7 ℃/min to obtain the lithium-rich manganese-based layered material with the surface doped with sulfur and the lithium sulfate protective layer.
The material is used as an active material, the initial cycle specific capacity of the assembled battery is 152.3mAh/g in the 1C rate circulation process at 30 ℃, the capacity is only 41.5mAh/g after 50 weeks of circulation, and the capacity retention rate is 27.25%.
Comparative example 3
(1) Grinding and dispersing elemental sulfur powder in absolute ethyl alcohol uniformly, and then adding lithium-rich manganese-based layered material Li 1.2 Mn 0.6 Ni 0.2 O 2 After uniform ultrasonic dispersion, heating to 70 ℃, stirring, evaporating to dryness, and vacuum drying at 80 ℃ for 12 hours to obtain an intermediate product; wherein, the mol ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.06:1;
(2) And calcining the intermediate product at 270 ℃ for 6 hours under the oxygen atmosphere in the tubular furnace at the oxygen flow rate of 300mL/min, and heating at the heating rate of 3 ℃/min to obtain the lithium-rich manganese-based layered material with the surface doped with sulfur and the lithium sulfate protective layer.
The ICP-OES result of the material shows that the content of S element in the material is less than 0.01wt%.
The material is used as an active material, the initial cycle specific capacity of the assembled battery is 176.8mAh/g in the 1C rate circulation process at 30 ℃, the capacity after 50 weeks circulation is 119.7mAh/g, and the retention rate is 67.70%.
In view of the foregoing, it will be appreciated that the invention includes but is not limited to the foregoing embodiments, any equivalent or partial modification made within the spirit and principles of the invention.
Claims (7)
1. The utility model provides a surface sulfur doping and have lithium rich manganese basic unit material of lithium sulfate protective layer which characterized in that: the material is prepared by the following steps:
(1) Grinding and dispersing elemental sulfur powder in absolute ethyl alcohol uniformly, adding a lithium-rich manganese-based layered material, carrying out ultrasonic dispersion uniformly, heating, stirring, evaporating to dryness, and carrying out vacuum drying to obtain an intermediate product; wherein, the mol ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.01:1-0.1:1;
(2) Calcining the intermediate product for 4-8 hours at 200-300 ℃ under the oxygen atmosphere in a tube furnace at the oxygen flow rate of 60-200 mL/min and the heating rate of 6-12 ℃/min to obtain the lithium-rich manganese-based layered material with the surface doped with sulfur and the lithium sulfate protective layer.
2. A lithium-rich manganese-based layered material having a surface sulfur doped and having a lithium sulfate protective layer as claimed in claim 1, wherein: in the step (1), the lithium-rich manganese-based layered material is Li 1.2 Mn 0.6 Ni 0.2 O 2 。
3. A lithium-rich manganese-based layered material having a surface sulfur doped and having a lithium sulfate protective layer as claimed in claim 1, wherein: in the step (1), the mole ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.03:1-0.06:1.
4. A lithium-rich manganese-based layered material having a surface sulfur doped and having a lithium sulfate protective layer as claimed in claim 1, wherein: in the step (1), the vacuum drying temperature is 60-120 ℃ and the drying time is 10-12 h.
5. A lithium-rich manganese-based layered material having a surface sulfur doped and having a lithium sulfate protective layer as claimed in claim 1, wherein: in the step (2), the temperature rising rate during calcination is 8-10 ℃/min.
6. A lithium-rich manganese-based layered material having a surface sulfur doped and having a lithium sulfate protective layer as claimed in claim 1, wherein: in the step (2), the flow rate of oxygen is 80-150 mL/min.
7. A lithium-rich manganese-based layered material having a surface sulfur doped and having a lithium sulfate protective layer as claimed in claim 1, wherein: in step (1): the lithium-rich manganese-based layered material is Li 1.2 Mn 0.6 Ni 0.2 O 2 The method comprises the steps of carrying out a first treatment on the surface of the The mol ratio of the elemental sulfur powder to the lithium-rich manganese-based positive electrode material is 0.03:1-0.06:1; vacuum drying temperature is 60-120 deg.c and drying time is 10-12 hr; in the step (2): the temperature rising rate is 8-10 ℃/min during calcination; the flow rate of oxygen is 80 mL/min-150 mL/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210253380.4A CN114597368B (en) | 2022-03-15 | 2022-03-15 | Lithium-rich manganese-based layered material with surface sulfur doped and lithium sulfate protective layer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210253380.4A CN114597368B (en) | 2022-03-15 | 2022-03-15 | Lithium-rich manganese-based layered material with surface sulfur doped and lithium sulfate protective layer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114597368A CN114597368A (en) | 2022-06-07 |
| CN114597368B true CN114597368B (en) | 2023-10-31 |
Family
ID=81809308
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210253380.4A Active CN114597368B (en) | 2022-03-15 | 2022-03-15 | Lithium-rich manganese-based layered material with surface sulfur doped and lithium sulfate protective layer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114597368B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104218241A (en) * | 2014-09-30 | 2014-12-17 | 奇瑞汽车股份有限公司 | Lithium ion battery anode lithium-rich material modification method |
| CN106848227A (en) * | 2017-01-23 | 2017-06-13 | 合肥国轩高科动力能源有限公司 | A kind of preparation method of the modified lithium-rich manganese-based anode material in surface |
| CN108123128A (en) * | 2017-12-25 | 2018-06-05 | 北京理工大学 | Adulterate Al in a kind of surface layer3+NCM tertiary cathode materials preparation method |
| CN108807918A (en) * | 2018-06-15 | 2018-11-13 | 中南大学 | A kind of lithium-rich manganese-based anode material and preparation method thereof of surface covered composite yarn |
| WO2022007663A1 (en) * | 2020-07-07 | 2022-01-13 | 巴斯夫杉杉电池材料有限公司 | Lithium ion battery positive electrode active material and preparation method therefor |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103811743A (en) * | 2012-11-15 | 2014-05-21 | 华为技术有限公司 | Lithium-rich anode material, lithium battery anode and lithium battery |
-
2022
- 2022-03-15 CN CN202210253380.4A patent/CN114597368B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104218241A (en) * | 2014-09-30 | 2014-12-17 | 奇瑞汽车股份有限公司 | Lithium ion battery anode lithium-rich material modification method |
| CN106848227A (en) * | 2017-01-23 | 2017-06-13 | 合肥国轩高科动力能源有限公司 | A kind of preparation method of the modified lithium-rich manganese-based anode material in surface |
| CN108123128A (en) * | 2017-12-25 | 2018-06-05 | 北京理工大学 | Adulterate Al in a kind of surface layer3+NCM tertiary cathode materials preparation method |
| CN108807918A (en) * | 2018-06-15 | 2018-11-13 | 中南大学 | A kind of lithium-rich manganese-based anode material and preparation method thereof of surface covered composite yarn |
| WO2022007663A1 (en) * | 2020-07-07 | 2022-01-13 | 巴斯夫杉杉电池材料有限公司 | Lithium ion battery positive electrode active material and preparation method therefor |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114597368A (en) | 2022-06-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2023024651A1 (en) | Lithium iron manganese phosphate precursor, lithium iron manganese phosphate positive electrode material and preparation method therefor, electrode material, electrode, and lithium-ion battery | |
| US9559351B2 (en) | Nickel composite hydroxide particles and nonaqueous electrolyte secondary battery | |
| CN112151790B (en) | High-nickel ternary cathode material precursor, crystal face controllable growth method thereof, ternary cathode material and lithium ion battery | |
| CN115472819A (en) | Positive active material, positive pole piece and sodium ion battery | |
| JP6773047B2 (en) | Positive electrode material for non-aqueous electrolyte secondary battery and its manufacturing method, positive electrode mixture paste, non-aqueous electrolyte secondary battery. | |
| CN111435742A (en) | Positive active material, positive pole piece and sodium ion battery | |
| TWI482740B (en) | Lithium nickel manganese oxide composite material, method for making the same, and lithium battery using the same | |
| CN106784726B (en) | Lithium vanadyl phosphate modified lithium-rich manganese-based layered lithium ion battery cathode material and preparation method thereof | |
| CN102544444B (en) | Preparation method for lithium ion battery anode active material | |
| JP7159639B2 (en) | Method for producing particles of transition metal composite hydroxide, and method for producing positive electrode active material for lithium ion secondary battery | |
| Zhou et al. | CeO 2 coating to improve the performance of Li [Li 0.2 Mn 0.54 Ni 0.13 Co 0.13] O 2 | |
| Zhou et al. | Study of spherical Li1. 2-xNaxMn0. 534Ni0. 133Co0. 133O2 cathode based on dual Li+/Na+ transport system for Li-ion batteries | |
| Yu et al. | Enhanced rate performance and high current cycle stability of LiNi0. 8Co0. 1Mn0. 1O2 by sodium doping | |
| Meng et al. | Magnesium-doped Li [Li 0.2 Mn 0.54 Ni 0.13 Co 0.13] O 2 cathode with high rate capability and improved cyclic stability | |
| CN109216692B (en) | Modified ternary cathode material, preparation method thereof and lithium ion battery | |
| Zhang et al. | Ni-doping to improve the performance of LiFeBO3/C cathode material for lithium-ion batteries | |
| CN114649526B (en) | Inner-high-outer low-gradient doped lithium-rich manganese-based layered material and preparation method thereof | |
| CN112242502A (en) | Positive electrode material, modification method thereof and battery | |
| CN114597368B (en) | Lithium-rich manganese-based layered material with surface sulfur doped and lithium sulfate protective layer | |
| CN113745514B (en) | Fluorine-doped and lithium silicate-coated lithium-rich manganese-based positive electrode material and preparation method and application thereof | |
| CN113113588B (en) | Method for preparing lithium fast ion conductor material coated high-nickel ternary layered oxide by using covalent interface engineering strategy | |
| CN114864894A (en) | High-pressure-resistant coating-layer-modified lithium-rich manganese-based positive electrode material and preparation method and application thereof | |
| Wang et al. | Improving the electrochemical performance of Ni-rich cathode materials using a fast ion conductor coating of Li2O–B2O3–LiBr | |
| CN114566647A (en) | Calcium phosphate coated high-nickel ternary cathode material and preparation method and application thereof | |
| CN115036486B (en) | Polyvinylpyrrolidone-induced vanadium sodium phosphate composite positive electrode material, and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |