CN113690408A - Method for preparing interface between composite metal lithium electrode and solid electrolyte - Google Patents
Method for preparing interface between composite metal lithium electrode and solid electrolyte Download PDFInfo
- Publication number
- CN113690408A CN113690408A CN202110975421.6A CN202110975421A CN113690408A CN 113690408 A CN113690408 A CN 113690408A CN 202110975421 A CN202110975421 A CN 202110975421A CN 113690408 A CN113690408 A CN 113690408A
- Authority
- CN
- China
- Prior art keywords
- lithium
- solid electrolyte
- metal
- metal lithium
- composite
- 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 153
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 114
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 93
- 239000002184 metal Substances 0.000 title claims abstract description 93
- 239000002131 composite material Substances 0.000 title claims abstract description 70
- 239000007784 solid electrolyte Substances 0.000 title claims abstract description 70
- 238000000034 method Methods 0.000 title claims abstract description 31
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 45
- 239000011889 copper foil Substances 0.000 claims abstract description 33
- 238000003756 stirring Methods 0.000 claims abstract description 23
- 150000002641 lithium Chemical class 0.000 claims abstract description 15
- 238000010438 heat treatment Methods 0.000 claims abstract description 14
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 12
- 239000001301 oxygen Substances 0.000 claims abstract description 12
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 12
- 238000002156 mixing Methods 0.000 claims abstract description 9
- 239000010949 copper Substances 0.000 claims description 14
- 229910052802 copper Inorganic materials 0.000 claims description 12
- 239000003792 electrolyte Substances 0.000 claims description 12
- 238000006243 chemical reaction Methods 0.000 claims description 11
- 239000011248 coating agent Substances 0.000 claims description 7
- 238000000576 coating method Methods 0.000 claims description 7
- 239000007773 negative electrode material Substances 0.000 claims description 7
- 239000010935 stainless steel Substances 0.000 claims description 7
- 229910001220 stainless steel Inorganic materials 0.000 claims description 7
- 239000011224 oxide ceramic Substances 0.000 claims description 3
- 229910052574 oxide ceramic Inorganic materials 0.000 claims description 3
- 239000000919 ceramic Substances 0.000 claims description 2
- 230000008569 process Effects 0.000 abstract description 7
- 239000007787 solid Substances 0.000 abstract description 7
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical group [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 abstract description 4
- 229910001416 lithium ion Inorganic materials 0.000 abstract description 4
- 238000002360 preparation method Methods 0.000 abstract description 4
- 238000002844 melting Methods 0.000 abstract description 3
- 230000008018 melting Effects 0.000 abstract description 3
- 230000008021 deposition Effects 0.000 abstract description 2
- 239000011159 matrix material Substances 0.000 abstract 1
- 239000013354 porous framework Substances 0.000 abstract 1
- 210000004027 cell Anatomy 0.000 description 9
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 8
- 238000012360 testing method Methods 0.000 description 8
- 229910011687 LiCu Inorganic materials 0.000 description 6
- 238000009736 wetting Methods 0.000 description 6
- 229910000881 Cu alloy Inorganic materials 0.000 description 5
- OPHUWKNKFYBPDR-UHFFFAOYSA-N copper lithium Chemical compound [Li].[Cu] OPHUWKNKFYBPDR-UHFFFAOYSA-N 0.000 description 5
- 229910052786 argon Inorganic materials 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 239000002223 garnet Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000005275 alloying Methods 0.000 description 2
- 238000003487 electrochemical reaction Methods 0.000 description 2
- 239000007772 electrode material Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 239000000758 substrate Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000002228 NASICON Substances 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000003490 calendering Methods 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 210000001787 dendrite Anatomy 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 239000002019 doping agent Substances 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000000840 electrochemical analysis Methods 0.000 description 1
- 238000005868 electrolysis reaction Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 229910003480 inorganic solid Inorganic materials 0.000 description 1
- 229910003473 lithium bis(trifluoromethanesulfonyl)imide Inorganic materials 0.000 description 1
- QSZMZKBZAYQGRS-UHFFFAOYSA-N lithium;bis(trifluoromethylsulfonyl)azanide Chemical compound [Li+].FC(F)(F)S(=O)(=O)[N-]S(=O)(=O)C(F)(F)F QSZMZKBZAYQGRS-UHFFFAOYSA-N 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- JMANVNJQNLATNU-UHFFFAOYSA-N oxalonitrile Chemical compound N#CC#N JMANVNJQNLATNU-UHFFFAOYSA-N 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 239000007774 positive electrode material Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 229910052715 tantalum Inorganic materials 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 238000001291 vacuum drying Methods 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 229910052726 zirconium Inorganic materials 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
- H01M4/134—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
- 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
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0561—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of inorganic materials only
- H01M10/0562—Solid materials
-
- 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
- H01M4/04—Processes of manufacture in general
- H01M4/0402—Methods of deposition of the material
- H01M4/0407—Methods of deposition of the material by coating on an electrolyte layer
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2300/00—Electrolytes
- H01M2300/0017—Non-aqueous electrolytes
- H01M2300/0065—Solid electrolytes
- H01M2300/0068—Solid electrolytes inorganic
- H01M2300/0071—Oxides
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Inorganic Chemistry (AREA)
- Battery Electrode And Active Subsutance (AREA)
- Secondary Cells (AREA)
Abstract
The invention provides a preparation method of an interface between a composite metal lithium electrode and a solid electrolyte, which comprises the following steps: when the oxygen content and the water content are both lower than 1ppm, according to the mass ratio of the metal lithium to the copper foil of 20-100: 1, heating and melting the metal lithium, adding the metal lithium to the copper foil, mixing, and stirring at a high speed to form the composite metal lithium negative electrode with the metal frame. The modified lithium composite negative electrode is uniformly coated on the sintered oxide solid electrolyte, and the composite metal lithium is in good contact with the oxide solid electrolyte due to the high viscosity of the composite metal lithium, wherein the three-dimensional network-shaped porous framework is used as a matrix of the composite metal lithium negative electrode, so that the uneven deposition of lithium ions in the circulation process of the metal lithium battery and the volume expansion of the metal lithium negative electrode in the long circulation process can be effectively inhibited, and the ultra-long circulation solid battery is obtained.
Description
Technical Field
The invention belongs to the technical field of lithium ion batteries, and relates to a preparation method of an interface between an ultra-stable composite metal lithium electrode and an oxide solid electrolyte, and a lithium ion battery.
Background
Solid state lithium batteries have received much attention due to their excellent safety, high energy density, wider operating temperature and stability. A good solid lithium battery, the most important of which is solid electrolyte, and the currently mainstream inorganic solid electrolyte includes sulfide electrolyte, perovskite structure electrolyte, garnet structure electrolyte, NASICON structure electrolyte and the like. Murugan et al Li 20075La3M2O12Based on (M ═ Nb, Ta), Nb is replaced by Zr element, and Ta element is successfully synthesized into Li with high ionic conductivity7La3Zr2O12(LLZO) garnet structure oxide electrolyte (3X 10)-4 S cm -125 deg.C), the ionic conductivity of the solid electrolyte is superior to that of all solid electrolytes reported previously, because the oxide solid electrolyte and the dopant thereof have the advantages of higher electrochemical window, higher ionic conductivity and stable reaction with metallic lithium, and the oxide solid electrolyte is led to the research of a large number of scholars. However, the oxide solid electrolyte has strong mechanical properties, so that the oxide solid electrolyte has very large interfacial resistance with a lithium metal cathode, thereby limiting the application of the oxide solid electrolyte.
In view of the problem of large interfacial resistance between the oxide solid electrolyte and the lithium metal negative electrode, Hu et al modify the surface of the oxide solid electrolyte by PLD technology to plate a lithium-philic plating layer Si on the surface of the solid electrolyte, but this method is expensive, and refer to the following document 1. Sun et al modified the surface of oxide solid electrolyte by PLD technique and plated a lithium-philic Cu layer on the surface of solid electrolyte3N, thereby forming an SEI that inhibits the growth of lithium dendrites, but the plating layer is easily detached during a long cycle of the battery to cause the failure of the battery, refer to the following document 2.
Luwei et al disclose a composite lithium metal negative electrode, which is composed of lithium metal and graphite, and is composed of lithium metal and carbon nitride, a method for preparing the same, and an interface improvement in a solid electrolyte, wherein the composite lithium metal can only improve the interface without considering the stability of the battery under a long cycle condition, and refer to documents 3 and 4 below.
Document 1: transition from Superlithiophability to Superlithiophability of Garnet Solid-State Electrolysis; JACS,2016,138, 12258-12262;
document 2 Design of a mixed reduced gate/Li interface for dense-free solid metallic bateries; energy Environmental Science,2020,13, 127-;
document 3: chinese patent 201910020636.5;
document 4, chinese patent 201910155649.3;
however, the above-described solution to the problem of the interface between the metallic lithium and the oxide solid electrolyte does not take into account the influence of the volume expansion of the metallic negative electrode on the interface stability under a long time or large current cycle of the battery.
Disclosure of Invention
In order to solve the problems of large interface impedance between an oxide solid electrolyte and a metal lithium cathode and volume expansion of the metal lithium cathode in the battery cycle process, the invention provides a novel method for preparing the metal lithium electrode, the method can conveniently dope a copper three-dimensional network porous metal framework in the metal cathode, the composite metal lithium cathode has larger viscosity and can be in very good contact with the oxide solid electrolyte in a molten state, in addition, based on the doped copper three-dimensional network-shaped porous metal framework, the charge circulation in the metal lithium negative electrode is uniform, the uniformity of electrochemical reaction of the metal lithium as an electrode active material is greatly improved, thereby promoting the uniform deposition of lithium ions to a very high degree and also inhibiting the volume expansion of the metal lithium electrode in the battery cycle process, thereby obtaining an ultra-stable solid electrolyte and metal lithium interface.
Compared with the method for improving the interface resistance by modifying the solid electrolyte interface and modifying the metal lithium cathode, the high-viscosity composite metal lithium prepared by the method disclosed by the invention is in good contact with the solid electrolyte, so that the interface resistance problem is solved, in addition, the metal lithium electrode taking the battery electrode framework material as the substrate can inhibit the volume expansion problem of the electrode to a certain extent in the battery circulation process, the interface stability is well ensured, and the solid full battery assembled by taking the composite metal lithium electrode as the cathode has very good electrochemical circulation performance.
In order to achieve the above object, the present invention provides a method for preparing an interface between a composite metal lithium electrode and a solid electrolyte, comprising the steps of: s1, heating the lithium metal to 200 ℃ by using stainless steel as a reaction container to melt the lithium metal; s2, controlling the oxygen content to be lower than 1ppm and the water content to be lower than 1ppm, adding a copper foil into molten metal lithium, and mixing to form a lithium melt, wherein the mass ratio of the metal lithium to the copper foil is controlled to be 20-100: 1; s3, stirring the lithium melt at a high speed at a stirring speed of 800-15000 r/min for 1-8 hours to ensure that the copper foil is uniformly distributed in the molten lithium metal to form molten composite lithium metal, so that the copper is fully reacted; s4, uniformly coating the modified lithium composite negative electrode on the sintered oxide solid electrolyte at the temperature of 200-400 ℃, and fully contacting the solid electrolyte and the composite metal lithium by utilizing the high viscosity of the composite metal lithium, wherein each 1cm of the solid electrolyte is2And 1-30mg of modified lithium-based composite negative electrode material is coated on the solid electrolyte.
Preferably, the added copper foil has a thickness of 5 to 80 μm.
Preferably, the heating rate of the heating table is 2-4 ℃/min.
Preferably, the stirring speed is 1000 rpm and the stirring time is 2 hours.
Preferably, the oxide solid electrolyte ceramic sheet is one of polished smooth LLZO, LLZTO, LLZNO, LLZGO, and Al-LLZO.
Preferably, the electrolyte is oxide ceramic, the thickness is 0.8-2 mm, the diameter is 8-13 mm, the relative compactness is more than 90%, and the crystal phase is cubic phase.
Preferably, the viscosity of the lithium complex metal is measured by a viscometer.
Preferably, the pressure for installing the battery is controlled to be between 10 and 50 MPa.
Compared with the prior art, the invention has the following beneficial effects:
(1) the method can conveniently dope a copper three-dimensional network-shaped porous metal framework in the metal cathode, and the uniformity of electrochemical reaction of metal lithium as an electrode active material is greatly improved;
(2) compared with the method for modifying the interface of the solid electrolyte and modifying the negative electrode of the metal lithium, the method for modifying the interface resistance of the solid electrolyte has the advantages that the high-viscosity composite metal lithium prepared by the method is in good contact with the solid electrolyte, so that the problem of the interface resistance is solved;
(3) the metal lithium electrode taking the battery electrode framework material as the substrate can inhibit the problem of volume expansion of the electrode to a certain extent in the battery cycle process, the stability of an interface is well ensured, and the solid-state full battery assembled by taking the composite metal lithium electrode as the negative electrode has very good electrochemical cycle performance.
Drawings
Fig. 1 is an XRD result of a metal lithium electrode prepared in example 1 of the present invention;
FIGS. 2A-2B are front and rear photographs of a composite lithium metal infiltrated oxide solid state electrolyte prepared in example 1;
FIGS. 3A-3B are photographs of the wetting angle test of the lithium metal electrode prepared in example 1 and conventional untreated lithium metal with LLZTO;
FIGS. 4A-4B are low and high magnification photographs of an interfacial SEM of a composite metallic lithium and oxide solid-state electrolyte prepared in example 2;
FIGS. 5A-B are long cycle electrochemical test plots of a composite lithium metal symmetric cell made in example 3;
FIG. 6 is a comparison of limiting current tests for composite lithium metal symmetric cells and untreated pure lithium metal symmetric cells made in example 4;
fig. 7 is a cycle test chart of a full cell assembled by the composite lithium metal negative electrode and the ternary positive electrode material NCA prepared in example 5.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments that can be obtained by a person skilled in the art without making creative efforts based on the embodiments of the present invention belong to the protection scope of the present invention.
The key technology of the invention is a preparation method of an interface between a composite metal lithium electrode and a solid electrolyte, which comprises the following specific steps:
s1, heating the lithium metal to 200 ℃ by using stainless steel as a reaction container to melt the lithium metal;
s2, controlling the oxygen content to be lower than 1ppm and the water content to be lower than 1ppm, adding a copper foil into molten metal lithium, and mixing to form a lithium melt, wherein the mass ratio of the metal lithium to the copper foil is controlled to be 20-100: 1;
s3, stirring the lithium melt at a high speed at a stirring speed of 800-15000 r/min for 1-8 hours to ensure that the copper foil is uniformly distributed in the molten lithium metal to form molten composite lithium metal, so that the copper is fully reacted;
s4, uniformly coating the modified lithium composite negative electrode on the sintered oxide solid electrolyte at the temperature of 180-400 ℃, and fully contacting the solid electrolyte and the composite metal lithium by utilizing the high viscosity of the composite metal lithium, wherein each 1cm of the solid electrolyte is2And 1-30mg of modified lithium-based composite negative electrode material is coated on the solid electrolyte. The electrolyte is oxide ceramic, the thickness is 0.8-2 mm, the diameter is 8-13 mm, the relative density is more than 90%, and the crystal phase is cubic.
In the preparation method, all the processes are carried out in an environment with an oxygen content of less than 1ppm and a water content of less than 1ppm, it is necessary to heat and melt metallic lithium, and if the oxygen and water contents in the environment are too high, lithium reacts with oxygen and water at a high temperature. The steps prior to shaping of the lithium block are required to be carried out in an environment where the oxygen content is less than 1ppm and the water content is less than 1 ppm.
Adding copper foil into the molten lithium to mix, controlling the mass ratio of the metal lithium to the copper foil to be 20-100: 1, and stirring the lithium melt at a high speed at a stirring speed of more than 1000 revolutions per minute to uniformly distribute the copper foil in the molten metal lithium. Experiments show that under the conditions, lithium and copper can perform alloying reaction, the copper foil can not preserve the appearance of the copper foil due to the reaction, and a three-dimensional grid structure formed by nanometer-sized lithium copper alloy wires is remained in a lithium block after cooling. The stirring speed is preferably 1000 to 10000 rpm, the stirring time is preferably 1 to 8 hours, and the stirring time is more preferably 1000 rpm and 2 hours.
In a more preferred embodiment, the mass ratio of the metal lithium to the copper foil is controlled to be 15 to 25:1, preferably 18 to 20: 1. The copper foil refers to electronic-grade copper foil (with purity of more than 99.7% and thickness of 5-105 um) commonly used in printed circuit board conductor in electronic industry, and common two major types of calendered copper foil and electrolytic copper foil can be used. In a preferred embodiment, the added copper foil has a thickness of 5 to 80 μm, and this basic copper foil is easy to produce a three-dimensional network-like porous metal skeleton having excellent quality.
In a preferred embodiment, the lithium metal is heated and melted at the temperature of 200-400 ℃, the heating rate of the heating table is 2-4 ℃/min, and at the temperature, the copper foil and the lithium metal are subjected to alloying reaction to finally form a lithium-copper alloy nano three-dimensional framework.
The lithium electrode sheet prepared by the method can be directly used for a solid lithium battery, has excellent cycle characteristics, and specifically, referring to the examples, the pressure for loading the battery is controlled to be 10-50 MPa.
The details of the present invention are illustrated in more detail by the following examples and specific procedures, but the scope of the present invention is not limited to the following examples.
Example 1
Preparing a metal lithium electrode according to the following steps:
(1) introducing high-purity argon into a glove box so that the oxygen content in the box is less than 1ppm and the water content in the box is less than 1ppm, heating metal lithium to 200 ℃ by using a stainless steel reaction container to melt the metal lithium, and then, according to the mass ratio of the metal lithium to the copper of 100:1, adding copper foil with the thickness of 5 mu m, mixing, stirring at high speed for 1000 r/min, and stirring for 2 h;
(2) the modified lithium composite negative electrode is uniformly coated on the sintered oxide solid electrolyte, and the solid electrolyte is fully contacted with the composite metal lithium by utilizing the high viscosity of the composite metal lithium, wherein each 1cm of the solid electrolyte is2Coating 1mg of modified lithium-based composite negative electrode material on the solid electrolyte;
fig. 1 shows XRD results of metal lithium electrodes prepared in example 1 of the present invention with different stirring times of 10min and 2h, different from XRD spectra of metal lithium and copper, the standard peaks of lithium are at 52.1 ° and 65.1 °, and the standard peaks of copper are at 43.4 °, 50.6 ° and 74.2 °. The composite metal lithium has lithium copper alloy peaks different from metal lithium Li and copper Cu at 42.9 deg., 50.0 deg. and 73.4 deg., and after stirring for 2 hr, the XRD peaks of copper in the composite metal lithium disappear and are converted into lithium copper alloy peaks, and LiCuxA lithium copper alloy type composite lithium negative electrode is shown.
Fig. 2A and fig. 2B show the wetting process of the lithium metal electrode and the molten composite metal lithium in LLZTO prepared in example 1 of the present invention, respectively, and the molten composite metal lithium covers the whole LLZTO after 20 s.
FIGS. 3A and 3B are the wetting angle test of the lithium metal electrode prepared in example 1 of the present invention and the conventional untreated lithium metal with LLZTO, respectively, and the prepared LiCu in the molten state is compoundedxAnd ordinary untreated lithium Li was titrated on the solid electrolyte LLZTO, and the wetting angle was observed, from which it can be seen that the prepared composite metal lithium LiCu was obtainedxAnd LLZTO, the wetting angle theta is 36.1 deg., which is less than the 60 deg. wetting angle theta of the common lithium metal Li and the solid electrolyte LLZTO, indicating that the composite lithium metal LiCu is comparable to the common lithium metal LixHas better affinity for the oxide electrolyte, solid electrolyte LLZTO.
Example 2
Preparing a metal lithium electrode according to the following steps:
(1) introducing high-purity argon into a glove box so that the oxygen content in the box is less than 1ppm and the water content in the box is less than 1ppm, heating metal lithium to 200 ℃ by using a stainless steel reaction vessel for melting, and then adding a copper foil with the thickness of 10 mu m for mixing, wherein the mass ratio of the metal lithium to the copper foil is 80: 1, stirring at a high speed of 4000 revolutions per minute for 2 hours;
(2) the modified lithium composite negative electrode is uniformly coated on the sintered oxide solid electrolyte, and the solid electrolyte is fully contacted with the composite metal lithium by utilizing the high viscosity of the composite metal lithium, wherein each 1cm of the solid electrolyte is2Coating 10mg of modified lithium-based composite negative electrode material on the solid electrolyte;
fig. 4 is a SEM photograph of a cross section of the composite lithium metal prepared in example 2, wherein fig. 4B is an enlarged view of fig. 4A, and it can be seen that the prepared 3D metal skeleton is uniformly distributed in the lithium metal, and such a structure has very good electron conductivity, and can reduce the interfacial resistance of the negative electrode, and at the same time, can suppress the volume expansion of the lithium metal negative electrode during the cycle, thereby improving the cycle performance of the lithium battery. In addition, as shown in fig. 4, lithium composite negative electrode LiCuxThe contact with the solid electrolyte LLZTO is very good, and no obvious holes or gaps exist.
Example 3
Preparing a metal lithium electrode according to the following steps:
(1) introducing high-purity argon into a glove box so that the oxygen content in the box is less than 10ppm and the water content in the box is less than 10ppm, heating metal lithium to 300 ℃ by using a stainless steel reaction vessel for melting, and then adding a copper foil with the thickness of 15 mu m for mixing, wherein the mass ratio of the metal lithium to the copper foil is 60: 1, stirring at a high speed of 6000 rpm for 3 hours to form molten composite metal lithium;
(2) the modified lithium composite negative electrode is uniformly coated on the sintered oxide solid electrolyte, and the solid electrolyte is fully contacted with the composite metal lithium by utilizing the high viscosity of the composite metal lithium, wherein each 1cm of the solid electrolyte is2Coating 20mg of modified lithium-based composite negative electrode material on the solid electrolyte;
FIG. 5A,FIG. 5B shows the LiCu of the lithium button cell made from example 3x/LLZTO/LiCuxThe limit current density CCD test of button cell Li/LLZTO/Li assembled with common metal lithium, the symmetrical cell assembled with composite metal lithium is at 1.0mA/cm2The battery can be cycled, and the battery is symmetrical at 1.0mA/cm and is assembled by common metallic lithium2Short circuits occurred at current density, indicating that the stable interface between the lithium complex metal and the solid electrolyte was stable at high current, D1～D6Represents 0.1mA/cm2、0.2mA/cm2、0.4mA/cm2、0.6mA/cm2、0.8mA/cm2And 1.0mA · cm-2The current density.
FIG. 6 shows button cell LiCu assembled with lithium composite metal obtained in example 3x/LLZTO/LiCuxPerforming constant current long circulation test at 0.1mA/cm2The current density can be cycled for 10000h, which indicates that the stable interface between the composite metal lithium and the solid electrolyte is very stable.
Example 4
Testing of the lithium metal sheet cathode of the invention and conventional NCA cathode assembled battery
(1) Introducing high-purity argon into a glove box so that the oxygen content reading in the glove box is less than 1ppm and the water content is less than 1ppm, heating metal lithium to 400 ℃ to melt by using a stainless steel reaction vessel, adding a copper foil with the thickness of 50 microns, mixing, stirring at a high speed of 10000 rpm for 6 hours, wherein the mass ratio of the metal lithium to the copper foil is 20: 1;
(2) the modified lithium composite negative electrode is uniformly coated on the sintered oxide solid electrolyte, and the solid electrolyte is fully contacted with the composite metal lithium by utilizing the high viscosity of the composite metal lithium, wherein each 1cm of the solid electrolyte is2Coating 30mg of modified lithium-based composite negative electrode material on the solid electrolyte;
(3) weighing 90mg of commercial NCA powder material of Shenzhenjik crystal company and 5mg of coeqin for 30min, adding 5mg of adhesive PVDF, quickly grinding, adding a plurality of drops of NMP solvent within 1min, mixing the NMP solvent into slurry, drawing a film on an aluminum current collector by using a scraper of 50 mu m, then drying the aluminum current collector for 12 hours in a vacuum drying oven of 80 ℃, taking out the aluminum current collector, and punching an electrode plate into a wafer by using a punch, wherein the diameter of the electrode plate is 1.2 cm, and the thickness of the electrode plate is 30 mu m.
(4) The lithium metal sheet obtained in step (1) was used as a negative electrode, the NCA obtained in step (4) was used as a positive electrode, and the electrolyte was assembled into a full-cell LiCu using a coin cell case of 2032 using 5 μ L of LiTFSI/EC: DEC (v: 1) at a concentration of 1Mx/LLZTO/NCA。
(5) Circulating 500 times at 25 deg.C and 0.5C multiplying power, wherein 1C is 200 mAh/g.
Fig. 7 is a cycle test chart of an all-cell assembled by the composite lithium metal negative electrode manufactured in example 4 and the ternary NCA positive electrode manufactured as described above, wherein the left ordinate represents the specific discharge capacity, the right ordinate represents the efficiency, the abscissa represents the number of cycles, the cycle efficiency curve is the upper curve in the figure, the right arrow points to the efficiency ordinate, the specific discharge capacity curve is the lower curve in the figure, the left arrow points to the specific discharge capacity ordinate, and the specific discharge capacity curve reaches good electrochemical performance of 147mAh/g after 500 cycles.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention. As a result of the observation: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
Claims (8)
1. A method for preparing an interface between a composite metal lithium electrode and a solid electrolyte is characterized by comprising the following steps:
s1, heating the lithium metal to 200 ℃ by using stainless steel as a reaction container to melt the lithium metal;
s2, controlling the oxygen content to be lower than 1ppm and the water content to be lower than 1ppm, adding a copper foil into molten metal lithium, and mixing to form a lithium melt, wherein the mass ratio of the metal lithium to the copper foil is controlled to be 20-100: 1;
s3, stirring the lithium melt at a high speed at a stirring speed of 800-15000 r/min for 1-8 hours to ensure that the copper foil is uniformly distributed in the molten lithium metal to form molten composite lithium metal, so that the copper is fully reacted;
s4, uniformly coating the modified lithium composite negative electrode on the sintered oxide solid electrolyte at the temperature of 200-400 ℃, and fully contacting the solid electrolyte and the composite metal lithium by utilizing the high viscosity of the composite metal lithium, wherein each 1cm of the solid electrolyte is2And 1-30mg of modified lithium-based composite negative electrode material is coated on the solid electrolyte.
2. The method of claim 1, wherein the copper foil has a thickness of 5 μm to 80 μm.
3. The method of claim 1, wherein the heating stage has a heating rate of 2-4 ℃/min.
4. The method of claim 1, wherein the stirring speed is 1000 rpm and the stirring time is 2 hours.
5. The method of claim 1, wherein the oxide solid electrolyte ceramic sheet is one of polished smooth LLZO, LLZTO, LLZNO, LLZGO and Al-LLZO.
6. The method of claim 1, wherein the electrolyte is an oxide ceramic having a thickness of 0.8-2 mm, a diameter of 8-13 mm, a relative compactness of 90% or more, and a cubic phase.
7. The method of claim 1, wherein the lithium complex is tested for viscosity by a viscometer.
8. The method for preparing an interface between a composite metal lithium electrode and a solid electrolyte according to claim 1, wherein the pressure for charging the battery is controlled to be 10 to 50 MPa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110975421.6A CN113690408A (en) | 2021-08-24 | 2021-08-24 | Method for preparing interface between composite metal lithium electrode and solid electrolyte |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110975421.6A CN113690408A (en) | 2021-08-24 | 2021-08-24 | Method for preparing interface between composite metal lithium electrode and solid electrolyte |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113690408A true CN113690408A (en) | 2021-11-23 |
Family
ID=78581936
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110975421.6A Pending CN113690408A (en) | 2021-08-24 | 2021-08-24 | Method for preparing interface between composite metal lithium electrode and solid electrolyte |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113690408A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114300662A (en) * | 2021-12-28 | 2022-04-08 | 重庆大学 | Composite lithium and solid-state lithium battery |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08138725A (en) * | 1994-11-01 | 1996-05-31 | Matsushita Electric Ind Co Ltd | All solid lithium battery |
| CN109841811A (en) * | 2019-01-09 | 2019-06-04 | 同济大学 | A kind of lithium base negative electrode material and the preparation method and application thereof for solid state battery |
| WO2020050895A1 (en) * | 2018-09-04 | 2020-03-12 | Nanotek Instruments, Inc. | Lithium metal secondary battery containing two anode-protecting layers |
| CN111162265A (en) * | 2020-01-17 | 2020-05-15 | 中国人民解放军国防科技大学 | Preparation method of metal lithium composite negative electrode for solid-state battery |
| CN112349882A (en) * | 2020-11-06 | 2021-02-09 | 燕山大学 | Preparation method of metal lithium electrode and preparation method of three-dimensional network-shaped porous metal framework current collector |
-
2021
- 2021-08-24 CN CN202110975421.6A patent/CN113690408A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08138725A (en) * | 1994-11-01 | 1996-05-31 | Matsushita Electric Ind Co Ltd | All solid lithium battery |
| WO2020050895A1 (en) * | 2018-09-04 | 2020-03-12 | Nanotek Instruments, Inc. | Lithium metal secondary battery containing two anode-protecting layers |
| CN109841811A (en) * | 2019-01-09 | 2019-06-04 | 同济大学 | A kind of lithium base negative electrode material and the preparation method and application thereof for solid state battery |
| CN111162265A (en) * | 2020-01-17 | 2020-05-15 | 中国人民解放军国防科技大学 | Preparation method of metal lithium composite negative electrode for solid-state battery |
| CN112349882A (en) * | 2020-11-06 | 2021-02-09 | 燕山大学 | Preparation method of metal lithium electrode and preparation method of three-dimensional network-shaped porous metal framework current collector |
Non-Patent Citations (1)
| Title |
|---|
| 马嘉林等: "石榴石型固态电解质/铝锂合金界面构筑及电化学性能", 《电化学》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114300662A (en) * | 2021-12-28 | 2022-04-08 | 重庆大学 | Composite lithium and solid-state lithium battery |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111162265B (en) | Preparation method of metal lithium composite negative electrode for solid-state battery | |
| CN111725561B (en) | Solid electrolyte, preparation method thereof and all-solid-state battery | |
| CN112928238B (en) | Ultrathin metal lithium electrode, preparation thereof and application of ultrathin metal lithium electrode as negative electrode of secondary lithium battery | |
| CN114678517B (en) | Molten lithium battery negative electrode material, preparation method and all-solid-state lithium battery | |
| CN114267874A (en) | Geranite type sulfide solid electrolyte containing lithium halide coating layer and preparation method thereof | |
| CN112086678A (en) | Solid electrolyte, preparation method thereof and solid battery | |
| CN112349882A (en) | Preparation method of metal lithium electrode and preparation method of three-dimensional network-shaped porous metal framework current collector | |
| CN114156532B (en) | Multilayer composite solid electrolyte and preparation method thereof | |
| WO2015087948A1 (en) | Carbon material-coated metal porous body, collector, electrode, and power storage device | |
| JP2017027654A (en) | Carbon material-coated metal porous body, collector, electrode, and power storage device | |
| CN113690408A (en) | Method for preparing interface between composite metal lithium electrode and solid electrolyte | |
| Li et al. | In situ forming of ternary metal fluoride thin films with excellent Li storage performance by pulsed laser deposition | |
| CN114497707A (en) | High-performance low-cost composite solid electrolyte and preparation method and application thereof | |
| Liu et al. | Advanced Sn/C composite anodes for lithium ion batteries | |
| CN115411351A (en) | Solid-state battery modified by ion/electron mixed conductive solid interface layer and preparation method thereof | |
| CN114373933B (en) | Solid-state battery positive plate, preparation method thereof and solid-state battery | |
| CN113629231B (en) | Magnetically induced cobalt fiber/metallic lithium composite electrode material, and preparation method and application thereof | |
| CN112164778B (en) | Lithium cathode and preparation method thereof | |
| CN113036070A (en) | Negative active film layer and preparation method thereof, pre-lithiation method, negative pole piece and lithium battery | |
| Liu et al. | Dealloying-derived TiC hierarchical porous frameworks as stable host for advanced Li metal electrode | |
| Yan et al. | Enhanced electrochemical performance of garnet-based solid-state lithium metal battery with modified anodic and cathodic interfaces | |
| CN115117315B (en) | Silicon-oxygen negative electrode material, negative electrode plate, lithium battery and preparation method thereof | |
| CN115548342B (en) | 3D TiC composite material and preparation method and application thereof | |
| CN111952575B (en) | Inorganic Si-ZnO-Li composite material, preparation method and application thereof in lithium metal battery | |
| Liu et al. | Nano‐sheet and nano‐laminar vanadium nitride as anodes for high‐performance lithium‐ions storage |
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: 20211123 |
|
| RJ01 | Rejection of invention patent application after publication |