CN113097475A - Lithium-rich layered cathode material, preparation method thereof, battery cathode formed by lithium-rich layered cathode material and battery - Google Patents
Lithium-rich layered cathode material, preparation method thereof, battery cathode formed by lithium-rich layered cathode material and battery Download PDFInfo
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- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 71
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 71
- 239000010406 cathode material Substances 0.000 title claims abstract description 41
- 238000002360 preparation method Methods 0.000 title claims abstract description 24
- 238000000034 method Methods 0.000 claims abstract description 16
- 239000000126 substance Substances 0.000 claims abstract description 4
- IIPYXGDZVMZOAP-UHFFFAOYSA-N lithium nitrate Chemical compound [Li+].[O-][N+]([O-])=O IIPYXGDZVMZOAP-UHFFFAOYSA-N 0.000 claims description 28
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 26
- 229910052799 carbon Inorganic materials 0.000 claims description 26
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims description 21
- 239000002243 precursor Substances 0.000 claims description 21
- 238000001354 calcination Methods 0.000 claims description 20
- 238000010438 heat treatment Methods 0.000 claims description 18
- 239000011248 coating agent Substances 0.000 claims description 16
- 238000000576 coating method Methods 0.000 claims description 16
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 claims description 14
- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 claims description 14
- 239000002033 PVDF binder Substances 0.000 claims description 13
- 229910052782 aluminium Inorganic materials 0.000 claims description 13
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 13
- 239000011888 foil Substances 0.000 claims description 13
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims description 13
- 239000000243 solution Substances 0.000 claims description 13
- 238000001291 vacuum drying Methods 0.000 claims description 12
- 239000011247 coating layer Substances 0.000 claims description 11
- 238000001704 evaporation Methods 0.000 claims description 10
- 239000007774 positive electrode material Substances 0.000 claims description 10
- 239000002738 chelating agent Substances 0.000 claims description 9
- MIVBAHRSNUNMPP-UHFFFAOYSA-N manganese(2+);dinitrate Chemical compound [Mn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MIVBAHRSNUNMPP-UHFFFAOYSA-N 0.000 claims description 9
- KBJMLQFLOWQJNF-UHFFFAOYSA-N nickel(ii) nitrate Chemical compound [Ni+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O KBJMLQFLOWQJNF-UHFFFAOYSA-N 0.000 claims description 9
- 239000011572 manganese Substances 0.000 claims description 8
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 8
- 235000019270 ammonium chloride Nutrition 0.000 claims description 7
- 238000001035 drying Methods 0.000 claims description 6
- 239000007864 aqueous solution Substances 0.000 claims description 5
- 229910002651 NO3 Inorganic materials 0.000 claims description 4
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 claims description 4
- 239000010410 layer Substances 0.000 claims description 4
- 239000007788 liquid Substances 0.000 claims description 3
- 238000011068 loading method Methods 0.000 claims description 3
- 238000003980 solgel method Methods 0.000 claims description 2
- 239000000463 material Substances 0.000 abstract description 12
- 150000002500 ions Chemical class 0.000 abstract description 8
- 230000008569 process Effects 0.000 abstract description 7
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 abstract description 4
- 239000013078 crystal Substances 0.000 abstract description 4
- 229910001416 lithium ion Inorganic materials 0.000 abstract description 4
- 229910052723 transition metal Inorganic materials 0.000 abstract description 4
- 150000003624 transition metals Chemical class 0.000 abstract description 4
- 238000009792 diffusion process Methods 0.000 abstract description 3
- 230000005012 migration Effects 0.000 abstract description 2
- 238000013508 migration Methods 0.000 abstract description 2
- 230000009286 beneficial effect Effects 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 33
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 24
- 239000000460 chlorine Substances 0.000 description 15
- 238000003756 stirring Methods 0.000 description 14
- 238000007599 discharging Methods 0.000 description 12
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 10
- 229910052801 chlorine Inorganic materials 0.000 description 10
- 230000014759 maintenance of location Effects 0.000 description 10
- USYLIGCRWXYYPZ-UHFFFAOYSA-N [Cl].[Fe] Chemical compound [Cl].[Fe] USYLIGCRWXYYPZ-UHFFFAOYSA-N 0.000 description 9
- 239000003792 electrolyte Substances 0.000 description 9
- 229910052742 iron Inorganic materials 0.000 description 9
- 238000010586 diagram Methods 0.000 description 8
- 239000010405 anode material Substances 0.000 description 7
- -1 lithium hexafluorophosphate Chemical compound 0.000 description 7
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 6
- 235000011114 ammonium hydroxide Nutrition 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 description 5
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 description 5
- 238000001816 cooling Methods 0.000 description 5
- 239000008367 deionised water Substances 0.000 description 5
- 229910021641 deionized water Inorganic materials 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 239000012046 mixed solvent Substances 0.000 description 5
- 238000002156 mixing Methods 0.000 description 5
- 239000003960 organic solvent Substances 0.000 description 5
- 238000004080 punching Methods 0.000 description 4
- 150000001450 anions Chemical class 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 150000001768 cations Chemical class 0.000 description 2
- 230000001351 cycling effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000005303 weighing Methods 0.000 description 2
- 229910012820 LiCoO Inorganic materials 0.000 description 1
- 229910052493 LiFePO4 Inorganic materials 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Natural products N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000001938 differential scanning calorimetry curve Methods 0.000 description 1
- 239000007772 electrode material Substances 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000003002 pH adjusting agent Substances 0.000 description 1
- 238000001878 scanning electron micrograph Methods 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
- H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—Processes of manufacture
- H01M4/1391—Processes of manufacture of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
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- 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
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Abstract
The invention provides a lithium-rich layered cathode material, a preparation method thereof, a battery cathode and a battery, wherein the battery cathode and the battery are formed by the lithium-rich layered cathode material, and the lithium-rich layered cathode material has the following chemical general formula: li1.2Mn0.6‑x/ 2Ni0.2‑x/2FexO2‑yClyWherein the value of x is 0.01-0.05, and the value of y is 0.01-0.02. The lithium-rich layered cathode material is formed by doping ions into the lithium-rich layered cathode materialOriginal ions in the material have stronger binding force, so that transition metal migration to lithium sites in the charging process can be reduced, and the structural stability of the material can be enhanced; meanwhile, doped ions increase the crystal face spacing of the material, and are beneficial to the diffusion of lithium ions, so that the rate capability of the material is improved.
Description
Technical Field
The invention relates to a battery anode material, in particular to a lithium-rich layered anode material and a preparation method and application thereof.
Background
As the demand for large energy storage devices continues to increase, the search for high energy electrode materials is becoming increasingly urgent. Currently commercialized positive electrode material (e.g., LiCoO)2，LiFePO4) Their energy density is far from meeting the increasing demands at present. The specific capacity of the lithium-rich anode material can reach 250mAh g-1Above, the cutoff voltage exceeds 4.5V, and therefore has become one of the most interesting positive electrode materials.
However, the lithium-rich cathode material still has many problems to be solved, and when the voltage reaches above 4.5V in the first charging process, oxygen in the crystal lattice is irreversibly oxidized and removed from the crystal lattice, so that the whole material is changed.
In addition, after lithium ions are extracted during charging, adjacent transition metals occupy original lithium vacancies, so that lithium extracted during charging cannot be completely inserted back during discharging, and therefore, a large irreversible capacity loss exists.
Disclosure of Invention
In view of the above-mentioned shortcomings of the prior art, the present invention aims to provide a lithium-rich layered cathode material, a preparation method thereof, and a battery cathode and a battery formed by the same, which are used for solving the problem of capacity loss caused by the lithium battery in the charging and discharging processes in the prior art.
To achieve the above objects and other related objects, the present invention is achieved by the following technical solutions.
The invention firstly provides a lithium-rich layered cathode material, which has the following chemical general formula:
Li1.2Mn0.6-x/2Ni0.2-x/2FexO2-yCly，
wherein the value of x is 0.01-0.05, and the value of y is 0.01-0.02.
More preferably, x is 0.03 and y is 0.02 or 0.01.
According to the lithium-rich layered cathode material, the lithium-rich layered cathode material is prepared by adopting a sol-gel method.
The invention also provides a preparation method of the lithium-rich layered cathode material, which comprises the following steps:
1) preparation of a gel precursor: heating and evaporating the aqueous solution dissolved with the nitrate, the ammonium chloride and the chelating agent to form a gel precursor; the nitrate comprises manganese nitrate, nickel nitrate, lithium nitrate and ferric nitrate;
2) and (3) calcining: calcining for at least 2 hours at 400-500 ℃, and then calcining for at least 5 hours at 850-950 ℃ to form the lithium-rich layered cathode material.
According to the above process, the chelating agent is selected from citric acid.
According to the preparation method, the pH value of the aqueous solution is 6-8, such as 6, 7 or 8. The pH of the aqueous solution may be adjusted by a pH adjusting agent of the prior art, preferably, by aqueous ammonia.
According to the preparation method, the heating evaporation temperature is 60-85 ℃. For example, the temperature can be 60 ℃, 61 ℃, 62 ℃, 63 ℃, 64 ℃, 65 ℃, 66 ℃, 67 ℃, 68 ℃, 69 ℃, 70 ℃, 71 ℃, 72 ℃, 73 ℃, 74 ℃, 75 ℃, 76 ℃, 77 ℃, 78 ℃, 79 ℃, 80 ℃, 81 ℃, 82 ℃, 83 ℃, 84 ℃ or 85 ℃. According to the preparation method, the heating and the evaporation are carried out within the temperature range until the water is completely evaporated.
According to the preparation method, the molar ratio of nickel nitrate, manganese nitrate, lithium nitrate, ferric nitrate and ammonium chloride is (0.1-0.2): 0.5-0.6): 1.2-1.4): 0.02-0.04): 0.01-0.02.
According to the preparation method, before calcination, the gel precursor is subjected to vacuum drying, wherein the temperature of the vacuum drying is at least 80 ℃, and preferably 80-150 ℃. For example, the temperature may be 80 ℃, 90 ℃, 100 ℃, 110 ℃, 120 ℃, 130 ℃, 140 ℃ or 150 ℃.
According to the preparation method, the calcination can be carried out by using a muffle furnace. The temperature rise speed of the muffle furnace is 3-10 ℃/min.
According to the preparation method, the raw materials are calcined at 400-500 ℃ for 2-8 hours. Preferably, the calcination is carried out for at least 5 hours, otherwise the calcination time is too short to be successful.
According to the preparation method, the raw materials are calcined for 5-20 hours at 850-950 ℃. Preferably, the calcination is carried out for at least 12 hours, and the calcination time is too short to be successful.
The invention also discloses a battery anode formed by the lithium-rich anode material. The invention also discloses a battery anode, wherein the battery anode coating layer contains the lithium-rich layered anode material, PVDF and conductive carbon.
According to the battery anode, the battery anode comprises a carbon-containing aluminum foil layer, and the coating layer is arranged on the carbon-containing aluminum foil.
According to the battery anode, the mass ratio of the lithium-rich layered anode material to the PVDF to the conductive carbon is (5-10) to (0.5-3): 1.
according to the battery anode, the coating layer is formed by coating a coating liquid on the carbon-containing aluminum foil layer and drying the coating liquid; the coating solution was an NMP solution containing the positive electrode material, PVDF, and conductive carbon described above.
According to the battery anode, the loading amount of the lithium-rich layered anode material in the coating layer is 1-2 mg cm-2。
The amount of NMP used in the present application can be determined on a case-by-case basis.
According to the battery anode, vacuum drying can be adopted for drying, and the drying temperature is 80-200 ℃.
The application also discloses a battery, the positive electrode of the battery is as above, and the negative electrode of the battery is metallic lithium.
According to the above battery, the electrolyte is a lithium battery electrolyte, such as a lithium hexafluorophosphate solution.
The schematic diagram of the anion and cation co-doping in the lithium-rich layered cathode material is shown in fig. 1, and compared with an undoped sample, two cheap, nontoxic and environment-friendly anions (iron and chlorine respectively) are doped into the cobalt-free lithium-rich cathode material. Because the doped ions and the original ions in the material have stronger binding force, the transition metal can be reduced from migrating to lithium sites in the charging process, the interplanar spacing of the material is increased, the diffusion of lithium ions is facilitated, and the rate capability of the material is improved. In addition, the lithium-rich layered positive electrode can effectively solve the problem of capacity loss in the charging process, and the preparation method is simple to operate, low in cost, green and environment-friendly, and has a good application prospect.
Drawings
Fig. 1 shows a structural schematic diagram of co-doping of anions and cations in the lithium-rich layered cathode material of the present invention.
In fig. 2 a) shows XRD patterns of samples obtained according to comparative example 1 of the present invention without doping, obtained according to comparative example 2 with iron doping, obtained according to comparative example 3 with chlorine doping, and obtained according to example 1 with iron-chlorine double doping.
B) in fig. 2 is shown as an enlargement of the (003) and (104) planes of each of the samples in a).
In fig. 2 c) -f) are shown XRD trims for the undoped obtained in comparative example 1, iron-doped obtained in comparative example 2, chlorine-doped in comparative example 3 and iron-chlorine-double-doped samples in example 1.
Fig. 3 shows an SEM image of an iron-chlorine double-doped sample in example 1 of the present invention.
In fig. 4 a) is shown a first charge-discharge diagram of an undoped sample in comparative example 1 of the present invention.
B) in fig. 4 shows a first charge-discharge diagram of the fe-doped sample in comparative example 2 of the present invention.
In fig. 4 c) is shown a first charge-discharge diagram of the chlorine-doped sample in comparative example 3 of the present invention.
In fig. 4 d) is shown the first charge-discharge diagram of the fe-cl double doped sample in example 1 of the present invention.
Fig. 5 a) and b) show impedance plots of the inventive undoped comparative example 1, iron doped comparative example 2, chlorine doped comparative example 3 and iron-chlorine double doped example 1 before and after 100 cycles at 1C.
In fig. 5C) is a bar graph showing the interfacial resistance before and after 100 cycles at 1C for four cells formed by undoped comparative example 1, iron doped comparative example 2, chlorine doped comparative example 3 and iron-chlorine double doped example 1 according to the present invention.
In fig. 5 d) is shown a graph of rate performance and cycle at 0.2C for four cells formed by undoped comparative example 1, iron doped comparative example 2, chlorine doped comparative example 3 and iron-chlorine double doped example 1 according to the invention.
In fig. 5 e) is shown a cycle diagram at 55C and 1C for four cells according to the invention formed by undoped in comparative example 1, iron doped in comparative example 2, chlorine doped in comparative example 3 and iron-chlorine double doped in example 1.
In fig. 5 f) is shown a cycle diagram at room temperature and 1C for four cells formed by undoped comparative example 1, iron doped comparative example 2, chlorine doped comparative example 3 and iron-chlorine double doped example 1 according to the invention.
In fig. 5 g) is shown the DSC curves of four cells formed by undoped comparative example 1, iron doped comparative example 2, chlorine doped comparative example 3 and iron-chlorine double doped example 1 of the present invention charged to 4.8V at 0.2C.
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.
Furthermore, it is to be understood that one or more method steps mentioned in the present invention does not exclude that other method steps may also be present before or after the combined steps or that other method steps may also be inserted between these explicitly mentioned steps, unless otherwise indicated. Moreover, unless otherwise indicated, the numbering of the various method steps is merely a convenient tool for identifying the various method steps, and is not intended to limit the order in which the method steps are arranged or the scope of the invention in which the invention may be practiced, and changes or modifications in the relative relationship may be made without substantially changing the technical content.
The applicant provides a lithium-rich layered cathode material having the following chemical formula:
Li1.2Mn0.6-x/2Ni0.2-x/2FexO2-yClywherein the value of x is 0.01-0.05, and the value of y is 0.01-0.02.
The lithium-rich layered cathode material is a cathode and anode ion co-doped lithium-rich layered cathode material, the specific molecular structure is shown in figure 1, iron and chlorine are co-doped into the lithium-rich cathode material, and doped ions have stronger binding force with original ions in the material, so that transition metal migration to lithium sites in the charging process can be reduced, the crystal face spacing of the material is increased, the diffusion of lithium ions is facilitated, and the multiplying power performance of the material is finally increased.
The co-doped lithium-rich layered cathode material is used in the cathode of a battery, and the formed battery cathode can show good service performance.
Specifically, it is provided in the battery positive electrode in the form of a coating layer containing the lithium-rich layered positive electrode material described above, PVDF, and conductive carbon. Preferably, the loading amount of the lithium-rich layered cathode material in the coating layer is 1-2 mg cm-2. Preferably, the mass ratio of the lithium-rich layered cathode material to the PVDF to the conductive carbon is (5-10): 0.5-3): 1. preferably, the battery positive electrode comprises a carbon-containing aluminum foil layer, and the coating layer is arranged on the carbon-containing aluminum foil.
Further, the negative electrode of the battery is metallic lithium, and the electrolyte is a lithium battery electrolyte, such as a lithium hexafluorophosphate solution.
In order to further illustrate the performance of the lithium-rich layered cathode material and the performance of the battery cathode formed by using the same in the present application, specific examples and effect data are as follows.
Example 1
The preparation method of the lithium-rich layered cathode material in the embodiment includes the following steps:
1) weighing nickel nitrate, manganese nitrate, lithium nitrate, ferric nitrate and ammonium chloride in a molar ratio of 0.185:0.585: 1.32: 0.03: 0.02 (wherein the amount of lithium nitrate is 10% more). This was added to 50ml of deionized water and stirred for half an hour. Adding citric acid as chelating agent, stirring for half an hour, adding ammonia water to adjust pH to 7, stirring at 75 deg.C, and evaporating to obtain gel precursor.
2) And (3) drying the gel precursor in vacuum at 120 ℃ for one night, then putting the gel precursor into a muffle furnace to heat at the heating rate of 5 ℃/min, calcining the gel precursor for 5 hours at 450 ℃, then heating the gel precursor to 900 ℃ to calcine the gel precursor for 12 hours, and finally cooling the gel precursor to room temperature along with the furnace to form the lithium-rich layered cathode material. Is recorded as an iron-chlorine double-doped sample (Li)1.2Mn0.585Ni0.185Fe0.03O1.98Cl0.02Namely Fe&Cl-LNMO)。
The preparation method of the battery positive electrode in the embodiment is as follows:
mixing a lithium-rich layered cathode material, PVDF and conductive carbon in a mass ratio of 8: 1:1 adding NMP, stirring overnight by using small magnetons, and coating on a dried carbon-containing aluminum foil by using a coating machine; then dried in a vacuum drying oven at 120 ℃ for 12 h.
Forming a 12 mm-diameter wafer on a positive punching sheet of the battery by using a slicing machine, wherein the negative electrode is metal lithium, and the electrolyte is an organic solution of lithium hexafluorophosphate, and the organic solvent is a mixed solvent formed by ethylene carbonate and diethyl carbonate according to the volume ratio of 1: 1; a button cell battery of type CR2325 was assembled in the glove box.
Charging to 4.8V at constant current at room temperature under 1C current, discharging to 2V, and circulating for 500 times to obtain 158.9mAh g-1The capacity retention rate was 86.4%.
Charging to 4.8V by constant current at 55 deg.C and 1C current, discharging to 2V, and cycling for 100 times to obtain 232.2mAh g-1The capacity retention rate was 87.8%.
Example 2
The preparation method of the lithium-rich layered cathode material in the embodiment includes the following steps:
1) weighing nickel nitrate, manganese nitrate, lithium nitrate, ferric nitrate and ammonium chloride in a molar ratio of 0.185:0.585: 1.32: 0.03: 0.01% (wherein the amount of lithium nitrate was 10% more), was added to 50ml of deionized water, and stirred for half an hour. Adding citric acid as chelating agent, stirring for half an hour, adding ammonia water to adjust pH to 7, stirring at 75 deg.C, and evaporating to obtain gel precursor.
2) Vacuum drying the gel precursor at 120 deg.C for one night, heating in muffle furnace at a heating rate of 5 deg.C/min, calcining at 450 deg.C for 5 hr, heating to 900 deg.C, maintaining for 12 hr, and cooling to room temperature to obtain lithium-rich layered cathode material (Li)1.2Mn0.585Ni0.185Fe0.03O1.99Cl0.01)。
The preparation method of the battery positive electrode in the embodiment is as follows:
mixing a lithium-rich layered cathode material, PVDF and conductive carbon in a mass ratio of 8: 1:1 was added to NMP, stirred overnight with a small magnet, and coated on a dry carbon-containing aluminum foil using a coater. Then dried in a vacuum drying oven at 120 ℃ for 12 h.
Forming a 12 mm-diameter wafer on a battery anode, wherein the cathode is metal lithium, and an electrolyte is an organic solution of lithium hexafluorophosphate, wherein the organic solvent is a mixed solvent formed by ethylene carbonate and diethyl carbonate according to a volume ratio of 1: 1; a button cell battery of type CR2325 was assembled in the glove box.
Charging to 4.8V at constant current at room temperature under 1C current, discharging to 2V, and circulating for 500 times to obtain 135.8mAh g-1The capacity retention rate was 77.3%.
Charging to 4.8V by constant current at 55 deg.C and 1C current, discharging to 2V, and cycling for 100 times to obtain 221.1mAh g-1The capacity retention rate was 85.8%.
Comparative example 1
The comparative example is an undoped sample, as follows:
1) lithium nitrate, nickel nitrate and manganese nitrate are weighed in a molar ratio of 1.32:0.2:0.6 (wherein the amount of lithium nitrate is 10% more). This was added to 50ml of deionized water and stirred for half an hour. Adding citric acid as chelating agent, stirring for half an hour, adding ammonia water to adjust pH to 7, stirring at 75 deg.C, and evaporating to obtain gel precursor.
2) Condensing the mixtureDrying the glue precursor in vacuum at 120 deg.C for one night, heating in a muffle furnace at a heating rate of 5 deg.C/min, calcining at 450 deg.C for 5h, heating to 900 deg.C for 12h, and cooling to room temperature to obtain lithium-rich cathode material (Li)1.2Mn0.6Ni0.2O2I.e., LNMO).
The preparation method of the battery positive electrode in the embodiment is as follows:
mixing a lithium-rich layered material, PVDF and conductive carbon in a mass ratio of 8: 1:1 adding NMP, stirring overnight by using small magnetons, and coating on a dried carbon-containing aluminum foil by using a coating machine; then dried in a vacuum drying oven at 120 ℃ for 12 h.
Forming a 12 mm-diameter wafer on a positive punching sheet of the battery by using a slicing machine, wherein the negative electrode is metal lithium, and the electrolyte is an organic solution of lithium hexafluorophosphate, and the organic solvent is a mixed solvent formed by ethylene carbonate and diethyl carbonate according to the volume ratio of 1: 1; a button cell battery of type CR2325 was assembled in the glove box.
Charging to 4.8V at constant current at room temperature under 1C current, discharging to 2V, and circulating for 500 times to obtain 37.8mAh g-1The capacity retention rate was 26.4%.
Charging to 4.8V at 55 deg.C and 1C current, discharging to 2V, and circulating for 80 times to obtain 76.4mAh g-1The capacity retention rate was 33.8%.
Comparative example 2
This comparative example is an iron-doped sample, as follows:
1) lithium nitrate, nickel nitrate, manganese nitrate and ferric nitrate are weighed in a molar ratio of 1.32:0.185:0.585:0.03 (wherein the amount of lithium nitrate is added by 10%). This was added to 50ml of deionized water and stirred for half an hour. Adding citric acid as chelating agent, stirring for half an hour, adding ammonia water to adjust pH to 7, stirring at 75 deg.C, and evaporating to obtain gel precursor.
2) Vacuum drying the gel precursor at 120 deg.C for one night, heating in a muffle furnace at a temperature rise rate of 5 deg.C/min, calcining at 450 deg.C for 5 hr, heating to 900 deg.C, calcining for 12 hr, and cooling to room temperatureLithium-rich layered cathode material (Li)1.2Mn0.585Ni0.185Fe0.03O2I.e., Fe-LNMO).
The preparation method of the battery positive electrode in the embodiment is as follows:
mixing a lithium-rich layered cathode material, PVDF and conductive carbon in a mass ratio of 8: 1:1 adding NMP, stirring overnight by using small magnetons, and coating on a dried carbon-containing aluminum foil by using a coating machine; then dried in a vacuum drying oven at 120 ℃ for 12 h.
Forming a 12 mm-diameter wafer on a positive punching sheet of the battery by using a slicing machine, wherein the negative electrode is metal lithium, and the electrolyte is an organic solution of lithium hexafluorophosphate, and the organic solvent is a mixed solvent formed by ethylene carbonate and diethyl carbonate according to the volume ratio of 1: 1; a button cell battery of type CR2325 was assembled in the glove box.
Charging to 4.8V at constant current at room temperature under 1C current, discharging to 2V, and circulating for 500 times to obtain a product with a specific mass capacity of 122.0mAh g-1The capacity retention rate was 76.8%.
Charging to 4.8V at 55 deg.C and 1C current, discharging to 2V, and circulating for 80 times to obtain 194.0mAh g-1The capacity retention rate was 79.7%.
Comparative example 3
This comparative example is a chlorine doped sample, as follows:
1) lithium nitrate, nickel nitrate, manganese nitrate and ammonium chloride are weighed in a molar ratio of 1.32:0.2:0.6:0.02 (wherein the amount of lithium nitrate is added by 10%). This was added to 50ml of deionized water and stirred for half an hour. Adding citric acid as chelating agent, stirring for half an hour, adding ammonia water to adjust pH to 7, stirring at 75 deg.C, and evaporating to obtain gel precursor.
2) Vacuum drying the gel precursor at 120 deg.C for one night, heating in a muffle furnace at a heating rate of 5 deg.C/min, calcining at 450 deg.C for 5 hr, heating to 900 deg.C, calcining for 12 hr, and cooling to room temperature to obtain lithium-rich layered cathode material (Li)1.2Mn0.6Ni0.2O1.98Cl0.02I.e., Cl-LNMO).
The preparation method of the battery positive electrode in the embodiment is as follows:
mixing a lithium-rich layered cathode material, PVDF and conductive carbon in a mass ratio of 8: 1:1 adding NMP, stirring overnight by using small magnetons, and coating on a dried carbon-containing aluminum foil by using a coating machine; then dried in a vacuum drying oven at 120 ℃ for 12 h.
Forming a 12 mm-diameter wafer on a positive punching sheet of the battery by using a slicing machine, wherein the negative electrode is metal lithium, and the electrolyte is an organic solution of lithium hexafluorophosphate, and the organic solvent is a mixed solvent formed by ethylene carbonate and diethyl carbonate according to the volume ratio of 1: 1; a button cell battery of type CR2325 was assembled in the glove box.
Charging to 4.8V at constant current at room temperature under 1C current, discharging to 2V, and circulating for 500 times to obtain a product with a specific mass capacity of 102.0mAh g-1The capacity retention rate was 65.7%.
Charging to 4.8V at 55 deg.C and 1C current, discharging to 2V, and circulating for 80 times to obtain 162.4mAh g-1The capacity retention rate was 70.8%.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.
Claims (10)
1. The lithium-rich layered cathode material is characterized by having the following chemical general formula:
Li1.2Mn0.6-x/2Ni0.2-x/2FexO2-yCly，
wherein the value of x is 0.01-0.05, and the value of y is 0.01-0.02.
2. The lithium-rich layered cathode material is characterized in that the lithium-rich layered cathode material is prepared by a sol-gel method.
3. A method of preparing a lithium-rich layered positive electrode material as claimed in claim 1 or 2, comprising the steps of:
1) preparation of a gel precursor: heating and evaporating the aqueous solution dissolved with the nitrate, the ammonium chloride and the chelating agent to form a gel precursor; the nitrate comprises manganese nitrate, nickel nitrate, lithium nitrate and ferric nitrate;
2) and (3) calcining: calcining for at least 2 hours at 400-500 ℃, and then calcining for at least 5 hours at 850-950 ℃ to form the lithium-rich layered cathode material.
4. The method of claim 3, wherein the chelating agent is selected from the group consisting of citric acid;
and/or the pH value of the aqueous solution is 6-8;
and/or heating and evaporating at the temperature of 60-85 ℃;
and/or the molar ratio of nickel nitrate, manganese nitrate, lithium nitrate, ferric nitrate and ammonium chloride is (0.1-0.2): (0.5-0.6): 1.2-1.4): 0.02-0.04): 0.01-0.02);
and/or, before calcining, the method further comprises the step of drying the gel precursor in vacuum, wherein the temperature of the vacuum drying is at least 80 ℃.
5. A battery positive electrode formed by using the lithium-rich layered positive electrode material according to any one of claims 1 to 2.
6. A battery positive electrode comprising a coating layer containing the lithium-rich layered positive electrode material according to claim 5, PVDF and conductive carbon.
7. The battery positive electrode according to claim 6, wherein the mass ratio of the positive electrode material, PVDF and conductive carbon is (5-10) to (0.5-3): 1;
and/or the battery positive electrode comprises a carbon-containing aluminum foil, and the coating layer is arranged on the carbon-containing aluminum foil.
8. The battery positive electrode according to claim 6, wherein the coating layer is formed by coating the carbon-containing aluminum foil layer with a coating solution and drying the coating solution; the coating liquid contains the lithium-rich layered positive electrode material according to claim 5, PVDF and a NMP solution of conductive carbon.
9. The battery positive electrode according to claim 6, wherein the loading amount of the lithium-rich layered positive electrode material in the coating layer is 1-2 mg cm-2。
10. A battery according to any one of claims 5 to 9, wherein the positive electrode of the battery is the one according to any one of claims 5 to 9, and the negative electrode of the battery is metallic lithium.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117154086A (en) * | 2023-07-28 | 2023-12-01 | 南京大学 | Fe/Mg doping regulated layered lithium-rich cathode material, preparation method and lithium ion battery |
| WO2024026621A1 (en) * | 2022-08-01 | 2024-02-08 | 宁德时代新能源科技股份有限公司 | Modified lithium-rich manganese-based material, modification method of lithium-rich manganese-based material, secondary battery, and electrical device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104810519A (en) * | 2015-04-17 | 2015-07-29 | 奇瑞汽车股份有限公司 | Lithium ion battery cathode material rich in lithium and manganese and preparation method thereof |
| CN105895902A (en) * | 2014-12-25 | 2016-08-24 | 江南大学 | Synthesis of novel negative and positive ions Cl and Al-codoped modified rich-lithium layered positive electrode material |
| CN106410186A (en) * | 2016-11-17 | 2017-02-15 | 天津理工大学 | Preparation method and application of lithium-rich layered oxide cathode material |
| CN111463427A (en) * | 2020-04-15 | 2020-07-28 | 江南大学 | Chloride ion doped modified lithium-rich layered cathode material and preparation method thereof |
-
2021
- 2021-04-02 CN CN202110361390.5A patent/CN113097475A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105895902A (en) * | 2014-12-25 | 2016-08-24 | 江南大学 | Synthesis of novel negative and positive ions Cl and Al-codoped modified rich-lithium layered positive electrode material |
| CN104810519A (en) * | 2015-04-17 | 2015-07-29 | 奇瑞汽车股份有限公司 | Lithium ion battery cathode material rich in lithium and manganese and preparation method thereof |
| CN106410186A (en) * | 2016-11-17 | 2017-02-15 | 天津理工大学 | Preparation method and application of lithium-rich layered oxide cathode material |
| CN111463427A (en) * | 2020-04-15 | 2020-07-28 | 江南大学 | Chloride ion doped modified lithium-rich layered cathode material and preparation method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024026621A1 (en) * | 2022-08-01 | 2024-02-08 | 宁德时代新能源科技股份有限公司 | Modified lithium-rich manganese-based material, modification method of lithium-rich manganese-based material, secondary battery, and electrical device |
| CN117154086A (en) * | 2023-07-28 | 2023-12-01 | 南京大学 | Fe/Mg doping regulated layered lithium-rich cathode material, preparation method and lithium ion battery |
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