CN112563456A - Modified lithium metal negative electrode, preparation method thereof and button cell - Google Patents
Modified lithium metal negative electrode, preparation method thereof and button cell Download PDFInfo
- Publication number
- CN112563456A CN112563456A CN202011429412.9A CN202011429412A CN112563456A CN 112563456 A CN112563456 A CN 112563456A CN 202011429412 A CN202011429412 A CN 202011429412A CN 112563456 A CN112563456 A CN 112563456A
- Authority
- CN
- China
- Prior art keywords
- lithium metal
- negative electrode
- modified lithium
- gold
- lithium
- 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.)
- Pending
Links
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 72
- 150000002641 lithium Chemical class 0.000 title claims abstract description 51
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- PPTSBERGOGHCHC-UHFFFAOYSA-N boron lithium Chemical compound [Li].[B] PPTSBERGOGHCHC-UHFFFAOYSA-N 0.000 claims abstract description 44
- 229910000521 B alloy Inorganic materials 0.000 claims abstract description 36
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims abstract description 26
- 239000010931 gold Substances 0.000 claims abstract description 26
- 229910052737 gold Inorganic materials 0.000 claims abstract description 26
- XTHFKEDIFFGKHM-UHFFFAOYSA-N Dimethoxyethane Chemical compound COCCOC XTHFKEDIFFGKHM-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000011247 coating layer Substances 0.000 claims abstract description 14
- FDWREHZXQUYJFJ-UHFFFAOYSA-M gold monochloride Chemical compound [Cl-].[Au+] FDWREHZXQUYJFJ-UHFFFAOYSA-M 0.000 claims abstract description 12
- 239000002135 nanosheet Substances 0.000 claims abstract description 12
- 238000000034 method Methods 0.000 claims abstract description 10
- BSYLOTSXNQZYFW-UHFFFAOYSA-K trichlorogold;hydrate Chemical compound O.Cl[Au](Cl)Cl BSYLOTSXNQZYFW-UHFFFAOYSA-K 0.000 claims abstract description 8
- 239000011248 coating agent Substances 0.000 claims abstract description 4
- 238000000576 coating method Methods 0.000 claims abstract description 4
- 239000012043 crude product Substances 0.000 claims description 10
- 239000000243 solution Substances 0.000 claims description 10
- 239000002904 solvent Substances 0.000 claims description 9
- 239000000126 substance Substances 0.000 claims description 7
- 239000003792 electrolyte Substances 0.000 claims description 6
- 239000002002 slurry Substances 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 5
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- 239000002055 nanoplate Substances 0.000 claims description 5
- 239000012300 argon atmosphere Substances 0.000 claims description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 claims description 3
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 claims description 3
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 claims description 3
- 239000002033 PVDF binder Substances 0.000 claims description 3
- 239000006230 acetylene black Substances 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 claims description 3
- 239000011888 foil Substances 0.000 claims description 3
- 239000012535 impurity Substances 0.000 claims description 3
- 239000012528 membrane Substances 0.000 claims description 3
- 239000011259 mixed solution Substances 0.000 claims description 3
- 238000005498 polishing Methods 0.000 claims description 3
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims description 3
- 238000005406 washing Methods 0.000 claims description 3
- 238000005303 weighing Methods 0.000 claims description 3
- 239000012298 atmosphere Substances 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 229910013872 LiPF Inorganic materials 0.000 claims 1
- 101150058243 Lipf gene Proteins 0.000 claims 1
- 238000001291 vacuum drying Methods 0.000 claims 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 abstract description 18
- 230000001351 cycling effect Effects 0.000 abstract description 9
- 239000010410 layer Substances 0.000 abstract description 8
- 239000013078 crystal Substances 0.000 abstract description 6
- 238000009826 distribution Methods 0.000 abstract description 5
- 230000005684 electric field Effects 0.000 abstract description 5
- 230000002035 prolonged effect Effects 0.000 abstract description 3
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 abstract description 2
- 239000006181 electrochemical material Substances 0.000 abstract description 2
- 229910001416 lithium ion Inorganic materials 0.000 abstract description 2
- 239000000872 buffer Substances 0.000 abstract 1
- 238000000605 extraction Methods 0.000 abstract 1
- 238000003780 insertion Methods 0.000 abstract 1
- 230000037431 insertion Effects 0.000 abstract 1
- 210000004027 cell Anatomy 0.000 description 53
- 238000001878 scanning electron micrograph Methods 0.000 description 10
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 6
- 229910008290 Li—B Inorganic materials 0.000 description 5
- 229910045601 alloy Inorganic materials 0.000 description 5
- 239000000956 alloy Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 3
- 229910011115 Li7B6 Inorganic materials 0.000 description 2
- 229910001290 LiPF6 Inorganic materials 0.000 description 2
- 230000004931 aggregating effect Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000010406 cathode material Substances 0.000 description 2
- 210000001787 dendrite Anatomy 0.000 description 2
- 230000008021 deposition Effects 0.000 description 2
- 238000000921 elemental analysis Methods 0.000 description 2
- 230000010287 polarization Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
Images
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
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
- H01M4/139—Processes of manufacture
- H01M4/1395—Processes of manufacture of electrodes based on metals, Si or alloys
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
-
- 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
- H01M10/04—Construction or manufacture in general
- H01M10/0422—Cells or battery with cylindrical casing
- H01M10/0427—Button cells
-
- 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
-
- 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
- H01M4/134—Electrodes based on metals, Si or alloys
-
- 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
- H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
- H01M4/40—Alloys based on alkali metals
- H01M4/405—Alloys based on lithium
-
- 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
-
- 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
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
-
- 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
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/027—Negative electrodes
-
- 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
-
- 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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Nanotechnology (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Crystallography & Structural Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Composite Materials (AREA)
- Battery Electrode And Active Subsutance (AREA)
- Secondary Cells (AREA)
Abstract
The invention belongs to the technical field of electrochemical materials, and provides a modified lithium metal cathode, a preparation method thereof and a button cell, wherein a certain amount of gold chloride hydrate is weighed and added into ethylene glycol dimethyl ether to obtain a gold chloride solution with the concentration of 2mg/ml-5mg/ml, the surface of a lithium boron alloy is polished and then is immersed into the gold chloride solution for reaction to obtain the modified lithium metal cathode, the modified lithium metal cathode comprises an inner core and a coating layer, the coating layer provides uniform electric field distribution for the surface of the lithium boron alloy, reduces the actual current density, slows down the growth of dendritic crystals, effectively buffers the huge volume change during repeated lithium ion insertion and extraction, and obviously inhibits the generation of the dendritic crystals, thereby improving the cycle stability of the lithium metal cell. In the cycling process of the button cell obtained by the invention, lithium is firstly deposited in the gaps of the gold nanosheet layer and becomes a lithium coating, so that the problem of volume expansion of the cell is avoided, the thermal stability of the cell is effectively ensured, the capacity loss is reduced, and the cycle life of the cell is prolonged.
Description
Technical Field
The invention belongs to the technical field of electrochemical materials, and particularly relates to a modified lithium metal negative electrode, a preparation method thereof and a button cell.
Background
With the decreasing of traditional fossil energy reserves, the demand of people for new energy is more and more urgent, and the lithium battery as a high-energy density battery has the advantages of high working voltage, large specific energy, stable discharge voltage, long cycle life, no pollution and the like, is widely applied to small and light electronic devices, and is also a preferred power supply for future hybrid bikes and pure power automobiles.
The cathode material is one of the key materials of the lithium battery, and the lithium boron alloy has the obvious advantages of high specific energy, high specific power, low polarization and the like as a hot cathode material of a novel lithium battery. In the lithium boron alloy, Li7B6The lithium boron alloy has excellent electrochemical performance similar to that of pure lithium because the lithium in the matrix compound is also involved in the discharge process. When the lithium boron alloy is used as the cathode of the lithium metal battery, the three-dimensional framework of the lithium boron alloy can well relieve the problem of volume expansion in the circulation process, and the lithium boron alloy is based on the main body Li7B6Of constructionThe porosity, high conductivity and lithium affinity are beneficial to uniform deposition of lithium, the current density can be effectively reduced, and the formation of an SEI film is promoted. However, lithium metal batteries using a lithium boron alloy as the negative electrode also have serious practical development bottlenecks, such as volume expansion during cycling, dendrite growth to lower thermal stability of the battery, capacity loss due to formation of "dead lithium", irreversible consumption of lithium and electrolyte due to instability of SEI interface layer, increase of polarization voltage, and the like.
Disclosure of Invention
The present invention is made to solve the above problems, and an object of the present invention is to provide a modified lithium metal negative electrode, a method for preparing the same, and a button cell.
The invention provides a preparation method of a modified lithium metal negative electrode, which is characterized by comprising the following steps: step 1, weighing a certain amount of gold chloride hydrate in an argon atmosphere, adding the gold chloride hydrate into ethylene glycol dimethyl ether, and dissolving to obtain a gold chloride solution with the concentration of 2mg/mL-5 mg/mL; step 2, after polishing the surface of the lithium boron alloy, immersing the surface of the lithium boron alloy into a gold chloride solution for reaction for a period of time, so that the replaced gold simple substance is coated on the surface of the lithium boron alloy, and a crude product of the modified lithium metal cathode is obtained; and 3, washing and removing impurities from the crude product of the modified lithium metal negative electrode, and drying for a period of time in an inert atmosphere to obtain the modified lithium metal negative electrode.
In the method for producing a modified lithium metal negative electrode according to the present invention, the method may further include: wherein the gold simple substance exists in the form of gold nanosheets.
The present invention provides a modified lithium metal anode having features comprising: the core is a lithium boron alloy, the coating layer is formed by gathering gold nano-sheets, and the modified lithium metal negative electrode is prepared by the preparation method of the modified lithium metal negative electrode.
The modified lithium metal negative electrode provided by the present invention may further have the following characteristics: wherein the length of the gold nanoplates is 2nm-3 nm.
The invention provides a button cell, which is characterized by comprising the following components: the lithium ion battery comprises a positive pole piece, a negative pole piece, a diaphragm and electrolyte, wherein the negative pole piece is a modified lithium metal negative pole, and the diaphragm is a Celgard2400 diaphragm.
In the button cell provided by the invention, the button cell can also have the following characteristics: the preparation method of the positive pole piece comprises the following steps: step 1, adding a commercial lithium iron phosphate material, acetylene black and polyvinylidene fluoride into N-methyl-pyrrolidone at a volume ratio of 8:1:1 to obtain a prefabricated slurry of a positive pole piece; and 2, drawing the film of the prepared slurry on an aluminum foil, and drying the film for 12 hours in vacuum at 80 ℃ to obtain the positive pole piece.
In the button cell provided by the invention, the button cell can also have the following characteristics: wherein the electrolyte consists of a solute and a solvent, and the solute is 1mol/L LiPF6The solvent is a mixed solution of ethylene carbonate, dimethyl carbonate and diethyl carbonate in a volume ratio of 1:1:1, and the mass ratio of the solute to the solvent is 0.16.
Action and Effect of the invention
According to the preparation method of the modified lithium metal cathode, a certain amount of gold chloride hydrate is weighed in an argon atmosphere and added into ethylene glycol dimethyl ether to be dissolved to obtain a gold chloride solution with the concentration of 2mg/mL-5mg/mL, the surface of a lithium boron alloy is polished and then is immersed into the gold chloride solution for reaction, so that the replaced gold simple substance is coated on the surface of the lithium boron alloy to obtain a crude product of the modified lithium metal cathode, and the crude product is washed, purified and dried to obtain the modified lithium metal cathode.
The modified lithium metal negative electrode obtained by the invention comprises a core consisting of lithium boron alloy and a coating layer formed by gathering gold nanoplates. The highly conductive coating layer provides uniform electric field distribution for the surface of the lithium boron alloy, the actual current density is obviously reduced, and the growth of dendritic crystals is further slowed down.
The button cell obtained by the invention uses the modified lithium metal cathode as the cathode, and in the circulation process, lithium is firstly deposited in the gap of the gold nanosheet layer and then becomes a smooth and compact lithium coating, so that the problem of volume expansion of the cell is avoided, the thermal stability of the cell is effectively ensured, the capacity loss is reduced, and the cycle life of the cell is prolonged.
Drawings
Fig. 1 is a Scanning Electron Microscope (SEM) image of a coating layer of a modified lithium metal negative electrode obtained in example of the present invention;
fig. 2 is an elemental analysis chart (EDS chart) obtained by an X-ray spectrometer of a coating layer of the modified lithium metal negative electrode in the example of the invention;
fig. 3 is an SEM image of the lithium boron negative electrode in the full cell after cycling the button cell at 1C for 100 cycles in an embodiment of the invention;
fig. 4 is an SEM image of the lithium boron negative electrode in the full cell after cycling 100 cycles at 1C for a button cell with pure lithium boron alloy as the negative electrode;
FIG. 5 shows a button cell in an embodiment of the invention at a current density of 1.0mA cm-2The area capacity is 1.0mAh cm-2SEM images of the lithium boron negative electrode after 50 cycles of the following lower cycle;
FIG. 6 shows the current density of a button cell using pure Li-B alloy as the negative electrode at 1.0mA cm-2The area capacity is 1.0mAh cm-2SEM images of the lithium boron negative electrode after 50 cycles of lower cycling;
fig. 7 is a graph comparing the cycling performance of a button cell in an embodiment of the invention and a button cell with pure lithium boron alloy as the negative electrode cycled at 1C;
FIG. 8 shows the current density of the button cell and the button cell using pure Li-B alloy as the negative electrode in the example of the present invention at 1.0 mA-cm-2The area capacity is 1.0mAh cm-2Voltage versus time curve below.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the following embodiments are specifically described with reference to the accompanying drawings.
The raw materials and reagents used in the examples of the present invention were all obtained from general commercial sources unless otherwise specified.
Commercial lithium iron phosphate material was purchased from Aldrich;
celgard2400 membranes were purchased from Morgese, Nanjing.
< example 1>
This example describes in detail a modified lithium metal negative electrode and a method for preparing the same.
The preparation method of the modified lithium metal negative electrode of the present example is as follows:
step 2, after polishing the surface of the lithium boron alloy, immersing the surface of the lithium boron alloy into a gold chloride solution for reaction for 10s, so that the replaced gold simple substance is coated on the surface of the lithium boron alloy in a gold nanosheet form, and a crude product of the modified lithium metal cathode is obtained;
and 3, washing and removing impurities of the crude product of the modified lithium metal cathode by using ethylene glycol dimethyl ether, and drying for 10min in a glove box filled with argon to obtain the modified lithium metal cathode.
Fig. 1 is an SEM image of a coating layer of the modified lithium metal negative electrode obtained in this example, wherein (a) in fig. 1 is an SEM image at 13000 times, and (b) in fig. 1 is an SEM image at 19000 times.
The modified lithium metal negative electrode obtained in this example was tested using a JE0LJSM-7800FX ray spectrometer, yielding fig. 2.
Fig. 2 (a) is an overall morphology view of the modified lithium metal negative electrode in the present example, and fig. 2 (b) is an elemental analysis view (EDS view) of gold of the clad layer.
As shown in fig. 1-2, the surface of the modified lithium metal negative electrode prepared in this embodiment is coated with a uniform and dense coating layer, the coating layer is formed by aggregating gold nanoplates, and the distribution of the gold element in the modified lithium metal negative electrode is relatively uniform.
< example 2>
This example describes in detail a button cell using the modified lithium metal negative electrode obtained in example 1 as a negative electrode.
The button cell obtained in this example was prepared as follows:
step 2, taking the positive pole piece obtained in the step 1 as a positive pole, the modified lithium metal negative pole obtained in the example 1 as a negative pole, and Celgard2400 as a diaphragm, wherein the electrolyte consists of a solute and a solvent, and the solute is 1mol/L LiPF6The battery is assembled in a glove box filled with argon, and then stands for 12 hours to obtain the button battery, wherein the solvent is a mixed solution of ethylene carbonate, dimethyl carbonate and diethyl carbonate in a volume ratio of 1:1:1, and the volume ratio or mass ratio of a solute to the solvent is 0.16.
Fig. 3 is an SEM image of the lithium boron negative electrode in the full cell after the button cell in this example was cycled for 100 cycles at 1C, and fig. 4 is an SEM image of the lithium boron negative electrode in the full cell after the button cell with pure lithium boron alloy as the negative electrode was cycled for 100 cycles at 1C.
As shown in fig. 3 and 4, lithium is uniformly nucleated from the gaps of the gold nanosheets after the button cell is cycled for 100 cycles at 1C, and gradually tends to be flat, and a large amount of dendritic crystals are generated due to the nonuniform deposition of lithium after the button cell with pure lithium boron alloy as a negative electrode is cycled for 100 cycles at 1C, and the dendritic crystals can damage the thermal stability of the cell and even cause short circuit.
FIG. 5 shows the current density of the button cell in this example is 1.0mA cm-2The area capacity is 1.0mAh cm-2SEM image of modified lithium boron cathode in full cell after 50 cycles of lower cycle, and FIG. 6 shows that the current density of button cell using pure lithium boron alloy as cathode is 1.0mA cm-2The area capacity is 1.0mAh cm-2Lower circulationSEM image of modified lithium boron negative electrode in full cell after 50 cycles.
As shown in FIGS. 5 and 6, the current density of the button cell is 1.0mA cm-2The area capacity is 1.0mAh cm-2The lower cycle is still relatively flat lithium plating after 50 circles, and the current density of the button cell taking pure lithium boron alloy as the cathode is 1.0 mA-cm-2The area capacity is 1.0mAh cm-2After 50 cycles of the next cycle, a large number of dendrites are generated. The highly conductive gold nanosheet layer reduces the local current density through the abundant pores and the larger specific surface area, and improves the stability of the battery.
Electrochemical performance tests were performed on the button cell obtained in this example and the button cell using pure lithium boron alloy as the negative electrode using a CT2001A blue cell tester, to obtain fig. 7 and 8.
FIG. 7 is a graph showing the comparison of the cycling performance at 1C between the button cell of the present example and the button cell using pure Li-B alloy as the negative electrode, and FIG. 8 is a graph showing the comparison between the button cell of the present example and the button cell using pure Li-B alloy as the negative electrode at a current density of 1.0mA cm-2The area capacity is 1.0mAh cm-2Voltage versus time curve below.
As shown in fig. 7, the cycle performance curve of the button cell in this embodiment has 140mAhg-1The initial specific capacity is stable and circulates in the charging and discharging process of 500 circles, the cycling performance curve of the button cell taking pure lithium boron alloy as the cathode shows rapid capacity attenuation, the modified cathode provides uniform electric field distribution due to the gold nanosheet layer, and the modified cathode and a full cell consisting of lithium iron phosphate have higher initial specific capacity and good cycling stability.
As shown in FIG. 8, the current density of the button cell in this example is 1.0mA cm-2The area capacity is 1.0mAh cm-2The voltage-time curve still maintains 23mV stable overpotential in 1200h long circulation, and the button cell using pure Li-B alloy as cathode has current density of 1.0mA cm-2The area capacity is 1.0mAh cm-2The overpotential of the voltage-time curve is large and unstable, and the battery short circuit occurs after 400 h.The modification of the gold nanosheet layer in the modified negative electrode enables an electric field to be uniformly distributed, reduces the local current density and well improves the electrochemical performance of the battery.
Effects and effects of the embodiments
According to the preparation method of the modified lithium metal negative electrode related to embodiment 1, in an argon atmosphere, 300mg of gold chloride hydrate is weighed and added into 100ml of ethylene glycol dimethyl ether, a gold chloride solution with a concentration of 3mg/ml is obtained after dissolution, the surface of a lithium boron alloy is polished and then immersed into the gold chloride solution for reaction, the replaced gold simple substance is coated on the surface of the lithium boron alloy, a crude product of the modified lithium metal negative electrode is obtained, and the crude product is washed, purified and dried, so that the modified lithium metal negative electrode is obtained. The modified lithium metal negative electrode obtained in example 1 includes a core made of a lithium boron alloy and a coating layer formed by aggregating gold nanoplates. The highly conductive coating layer provides uniform electric field distribution for the surface of the lithium boron alloy, the actual current density is obviously reduced, and the growth of dendritic crystals is further slowed down.
The button cell obtained in the embodiment 2 uses the modified lithium metal negative electrode as the negative electrode, and in the circulation process, lithium is firstly deposited in the gap of the gold nanosheet layer and then becomes a flat and compact lithium coating, so that the problem of volume expansion of the cell is avoided, the thermal stability of the cell is effectively ensured, the capacity loss is reduced, and the cycle life of the cell is prolonged.
The above embodiments are preferred examples of the present invention, and are not intended to limit the scope of the present invention.
Claims (7)
1. A preparation method of a modified lithium metal negative electrode is characterized by comprising the following steps:
step 1, weighing a certain amount of gold chloride hydrate in an argon atmosphere, adding the gold chloride hydrate into ethylene glycol dimethyl ether, and dissolving to obtain a gold chloride solution with the concentration of 2mg/mL-5 mg/mL;
step 2, after polishing the surface of the lithium boron alloy, immersing the surface of the lithium boron alloy into the gold chloride solution for reaction for a period of time, so that the replaced gold simple substance is coated on the surface of the lithium boron alloy, and a crude product of the modified lithium metal cathode is obtained;
and 3, washing and removing impurities from the crude product of the modified lithium metal negative electrode, and drying for a period of time in an inert atmosphere to obtain the modified lithium metal negative electrode.
2. The method of preparing a modified lithium metal anode of claim 1, wherein:
wherein the gold simple substance exists in the form of gold nanosheets.
3. A modified lithium metal anode, comprising:
an inner core and a coating layer for coating the inner core,
wherein the inner core is lithium boron alloy,
the coating layer is formed by gathering gold nano-sheets,
the modified lithium metal negative electrode is produced by the method for producing a modified lithium metal negative electrode described in claim 1 or 2.
4. The modified lithium metal anode of claim 3, wherein:
wherein the length of the gold nanoplates is 2nm-3 nm.
5. A button cell battery, comprising:
a positive pole piece, a negative pole piece, a diaphragm and electrolyte,
wherein the negative pole piece is the modified lithium metal negative pole in claim 3 or 4,
the membrane was a Celgard2400 membrane.
6. The button cell according to claim 5, characterized in that:
the preparation method of the positive pole piece comprises the following steps:
step 1, adding a commercial lithium iron phosphate material, acetylene black and polyvinylidene fluoride into N-methyl-pyrrolidone according to a volume ratio of 8:1:1 to obtain a prefabricated slurry of the positive pole piece;
and 2, drawing the film of the prepared slurry on an aluminum foil, and performing vacuum drying for 12 hours at the temperature of 80 ℃ to obtain the positive pole piece.
7. The button cell according to claim 5, characterized in that:
the electrolyte consists of a solute and a solvent, wherein the solute is LiPF with the concentration of 1mol/L6The solvent is a mixed solution of ethylene carbonate, dimethyl carbonate and diethyl carbonate in a volume ratio of 1:1:1, and the mass ratio of the solute to the solvent is 0.16.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011429412.9A CN112563456A (en) | 2020-12-07 | 2020-12-07 | Modified lithium metal negative electrode, preparation method thereof and button cell |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011429412.9A CN112563456A (en) | 2020-12-07 | 2020-12-07 | Modified lithium metal negative electrode, preparation method thereof and button cell |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112563456A true CN112563456A (en) | 2021-03-26 |
Family
ID=75060938
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011429412.9A Pending CN112563456A (en) | 2020-12-07 | 2020-12-07 | Modified lithium metal negative electrode, preparation method thereof and button cell |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112563456A (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103972470A (en) * | 2013-01-25 | 2014-08-06 | 中国人民解放军63971部队 | Secondary lithium battery negative electrode with characteristic of lithium dendrite generation inhibition |
| CN105470466A (en) * | 2015-12-29 | 2016-04-06 | 中国电子科技集团公司第十八研究所 | All-solid-state battery of skeleton supported alloy anode and preparation method thereof |
| CN106784629A (en) * | 2017-01-19 | 2017-05-31 | 武汉大学 | A kind of lithium metal battery cathode interface method of modifying |
| CN106784764A (en) * | 2016-12-10 | 2017-05-31 | 浙江大学 | Lithium-oxygen battery with nitrogenous carbon-supported nanometer boron lithium alloy as anode material |
| US20190006664A1 (en) * | 2017-06-28 | 2019-01-03 | Panasonic Intellectual Property Management Co., Ltd. | Lithium secondary battery including electrolyte containing lithium boron compound |
| CN109216652A (en) * | 2018-08-01 | 2019-01-15 | 珠海光宇电池有限公司 | A kind of cathode of lithium and preparation method thereof of polymer protection |
| CN111082038A (en) * | 2019-11-28 | 2020-04-28 | 中南大学 | Low-boron-content lithium-boron alloy electrode material for lithium battery and application |
| CN111430684A (en) * | 2020-01-19 | 2020-07-17 | 蜂巢能源科技有限公司 | Composite negative electrode and preparation method and application thereof |
-
2020
- 2020-12-07 CN CN202011429412.9A patent/CN112563456A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103972470A (en) * | 2013-01-25 | 2014-08-06 | 中国人民解放军63971部队 | Secondary lithium battery negative electrode with characteristic of lithium dendrite generation inhibition |
| CN105470466A (en) * | 2015-12-29 | 2016-04-06 | 中国电子科技集团公司第十八研究所 | All-solid-state battery of skeleton supported alloy anode and preparation method thereof |
| CN106784764A (en) * | 2016-12-10 | 2017-05-31 | 浙江大学 | Lithium-oxygen battery with nitrogenous carbon-supported nanometer boron lithium alloy as anode material |
| CN106784629A (en) * | 2017-01-19 | 2017-05-31 | 武汉大学 | A kind of lithium metal battery cathode interface method of modifying |
| US20190006664A1 (en) * | 2017-06-28 | 2019-01-03 | Panasonic Intellectual Property Management Co., Ltd. | Lithium secondary battery including electrolyte containing lithium boron compound |
| CN109216652A (en) * | 2018-08-01 | 2019-01-15 | 珠海光宇电池有限公司 | A kind of cathode of lithium and preparation method thereof of polymer protection |
| CN111082038A (en) * | 2019-11-28 | 2020-04-28 | 中南大学 | Low-boron-content lithium-boron alloy electrode material for lithium battery and application |
| CN111430684A (en) * | 2020-01-19 | 2020-07-17 | 蜂巢能源科技有限公司 | Composite negative electrode and preparation method and application thereof |
Non-Patent Citations (1)
| Title |
|---|
| FEIHU GUO等: "Flaky and Dense Lithium Deposition Enabled by a Nanoporous Copper Surface Layer on Lithium Metal Anode", 《ACS MATERIALS LETTERS》 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113629236B (en) | Composite metal lithium cathode and preparation method and application thereof | |
| CN110993954A (en) | Negative current collector of lithium metal secondary battery and preparation method thereof | |
| CN103872330A (en) | Lithium ion battery negative electrode material and preparation method thereof | |
| CN109817887B (en) | High-volume energy density metal lithium battery | |
| CN115207263B (en) | Secondary battery | |
| CN111403678B (en) | Three-dimensional flexible metal cathode and preparation method thereof | |
| Wu et al. | A novel battery scheme: Coupling nanostructured phosphorus anodes with lithium sulfide cathodes | |
| CN109148851A (en) | A kind of silicon-carbon composite cathode material and preparation method thereof of double carbon structure modifications | |
| Liu et al. | Regulating Li nucleation/deposition by bamboo-shoot like lithiophilic particles anchored on carbon cloth for a dendrite-free lithium metal anode | |
| CN114284475A (en) | Preparation method of composite lithium metal cathode with three-dimensional structure and product thereof | |
| CN108987673B (en) | Lithium negative electrode containing conductive protection film and preparation method and application thereof | |
| CN110265650A (en) | A kind of lithium ion battery nanoporous composite negative pole material and preparation method thereof | |
| CN116470003A (en) | Pre-lithiated negative electrode piece and lithium ion battery | |
| CN115692706A (en) | Double-layer protective layer of metal lithium and interface modification method of metal lithium cathode | |
| CN112563456A (en) | Modified lithium metal negative electrode, preparation method thereof and button cell | |
| CN114583137A (en) | Method for modifying carbon surface by doping sulfur with phosphorus and application thereof | |
| CN115101731A (en) | Negative electrode material, preparation method thereof, negative electrode plate and secondary battery | |
| CN101478062A (en) | Composite electrolytic solution for lithium ionic battery, preparation and use thereof | |
| CN115207304A (en) | Graphite cathode composite material, preparation method thereof and lithium ion battery | |
| Zhang et al. | The high performance lithium metal composite anode by excessive alloying process | |
| CN113200530A (en) | Preparation method of carbon-coated nickel phosphide composite negative electrode material | |
| CN111710842A (en) | Metal lithium-aluminum oxide composite negative electrode for lithium battery and preparation method thereof | |
| CN111162283A (en) | Preparation method and application of nano porous foamed nickel current collector | |
| CN114512648B (en) | Three-dimensional porous substrate material for lithium metal battery negative electrode, and preparation method and application thereof | |
| CN113410451B (en) | Lithium metal negative electrode flexible protection material and preparation method 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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210326 |
|
| RJ01 | Rejection of invention patent application after publication |