CN110120502B - Lithium metal alloy negative electrode material and preparation method and application thereof - Google Patents

Lithium metal alloy negative electrode material and preparation method and application thereof Download PDF

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CN110120502B
CN110120502B CN201810110190.0A CN201810110190A CN110120502B CN 110120502 B CN110120502 B CN 110120502B CN 201810110190 A CN201810110190 A CN 201810110190A CN 110120502 B CN110120502 B CN 110120502B
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lithium
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张华�
俞海龙
黄学杰
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Institute of Physics of CAS
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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
    • 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
    • H01M4/13—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
    • 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
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    • H—ELECTRICITY
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    • 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
    • H01M4/381—Alkaline or alkaline earth metals elements
    • H01M4/382—Lithium
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    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
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    • 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
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Abstract

The invention provides a lithium metal alloy negative electrode material which comprises a lithium alloy serving as a framework and metal lithium filled in the framework. The lithium alloy has lithium ion conductivity, and compared with the traditional three-dimensional structure only having electronic conductivity, a better three-dimensional ion and electronic conductivity network can be formed, so that metal lithium is uniformly deposited, lithium dendrites can not be generated even if the metal lithium is charged and discharged under the condition of extremely high current density, and obvious battery polarization phase is not generated. According to the invention, a lithium alloy material capable of releasing lithium is adopted as a structural framework, and after metal lithium is depleted in the circulation process, the alloy framework can further release capacity, so that the circulation performance of the battery is ensured. The raw materials used by the invention have wide sources and low price, and the process is simple and is suitable for rapid large-scale production.

Description

Lithium metal alloy negative electrode material and preparation method and application thereof
Technical Field
The invention relates to the field of lithium ion battery cathode materials, in particular to a lithium metal alloy cathode material and a preparation method and application thereof.
Background
With the rapid development of mobile electronic devices, power cars and smart grids in recent years, higher requirements are made on the energy density of batteries. Graphite cathode-based lithium ion batteries have been developed over the last 30 years, the graphite cathode capacity has approached the theoretical capacity limit of 372mAh/g, and the energy density of graphite-based batteries has gradually approached the limit. In order to meet the rapid increase in the urgent demand for energy density of batteries, development of a negative electrode material having higher energy density is required. In recent years, the preparation of secondary lithium metal batteries with higher energy density using lithium metal cathodes with high specific capacity characteristics instead of conventional graphite-based cathodes has become an important research direction in the battery field.
The theoretical specific capacity of the metal lithium is as high as 3860mAh/g, which is 10 times higher than that of the graphite cathode. Compared with other alloy negative electrode materials with high specific capacity, such as silicon (theoretical capacity of 4200mAh/g) and tin (theoretical capacity of 994mAh/g), the metal lithium negative electrode has no absolute advantages in specific capacity, but has the characteristics of no need of mixing a conductive agent and a binder in the electrode preparation process, no huge volume expansion/shrinkage rate in the circulation process, relatively stable interface SEI, high ionic and electronic conductivity and the like, is more suitable for manufacturing a metal lithium battery with high rate performance and high energy density, and is also known as the final negative electrode of the lithium battery.
However, lithium ions in the metallic lithium negative electrode during battery cycling do not have uniform deposition/dissolution characteristics, resulting in formation of metallic lithium dendrite growth at the metallic lithium negative electrode. Metallic lithium dendrite growth can in turn initiate "dead lithium" accumulation ("dead lithium" refers to metallic lithium dendrites that are separated from the negative electrode and do not participate in subsequent electrochemical cycles), leading to a decay in the cyclable capacity. Meanwhile, dendrite growth of metallic lithium may penetrate the separator to cause a short circuit in the battery, causing ignition or explosion of the battery.
In recent years, researchers in various countries have tried various methods for suppressing the growth of metallic lithium dendrites in response to the above problems, and various techniques for suppressing the growth of metallic lithium dendrites have been developed. At present, the methods can be roughly classified into the following three methods according to the types: electrolyte optimization, interfacial barrier layer/artificial SEI (solid electrolyte interface layer) and three-dimensional negative electrode structure.
1. Electrolyte optimization
The effect of the electrolyte with high salt concentration is most remarkable in the optimization of the electrolyte. By additionally adding a large amount of lithium salt into the electrolyte, the lithium ion concentration difference of the electrolyte/metal lithium interface is weakened, and the Li content is reduced+The diffusion rate is not uniform at the near interface, thereby forming a uniform lithium metal deposit. For example, Zhang et al, using a 1-4M LiFSI DME electrolyte instead of a conventional electrolyte, found that the growth rate of metallic lithium dendrites can be significantly suppressed by increasing the concentration of lithium ions in the electrolyte.
However, the electrolyte with high salt concentration can obviously increase the viscosity of the electrolyte, and meanwhile, the addition of a large amount of anion groups can reduce the freedom degree of lithium ions in the electrolyte; the ionic conductivity of the electrolyte is reduced, the internal impedance of a battery system is increased, and the multiplying power cycle performance of the battery is greatly reduced. The addition of a large amount of lithium salt with high price in the electrolyte will also increase the manufacturing cost of the battery obviously and is not beneficial to promoting the industrial application of the metal lithium battery.
2. Interfacial barrier layer/artificial SEI
The interfacial barrier layer/artificial SEI achieves growth inhibition of metallic lithium dendrites by building an artificial negative SEI or a physical barrier layer with ionic conductivity on the surface of the metallic lithium. Such an interfacial layer reduces side reactions by blocking or reducing direct contact of the metallic lithium negative electrode with the electrolyte, and suppresses generation of metallic lithium dendrites by mechanical force. E.g. using Cu by Yi et al3And mixing the N nano particles and the butylbenzene rubber adhesive, and spin-coating the mixture on the surface of the current collector to form artificial SEI. Cu3N forms Li with high ionic conductivity during the first lithium deposition3The N solid electrolyte layer, and the mixed structure of the adhesive and the nano particles contains tiny gaps so that the electrolyte can be infiltrated. Li-Cu cells prepared using this artificial SEI in a carbonate electrolyte at 0.25mA/cm2The circulating coulombic efficiency under the current density can reach 98 percent, and is obviously superior to that of a control group.
However, the construction of interfacial barriers/artificial SEI's generally requires physical, chemical or electrochemical treatment of the lithium metal surface, is complex to process, and often does not allow the formation of a uniform large area capping layer. Meanwhile, the introduction of an additional interface layer inevitably increases the impedance of a battery system, reduces the rate capability and energy density of the battery, and is not suitable for being applied to a high-rate battery system.
3. Three-dimensional structure cathode
The three-dimensional structure negative electrode adopts a three-dimensional structure conductive current collector or a three-dimensional structure hollow nano material as a framework, and metal lithium is filled in the framework to form the composite negative electrode with a three-dimensional conductive network. The composite structure can effectively improve the electric field distribution in the metal lithium negative electrode and at the interface, inhibit the dendritic growth of the metal lithium through the porous microstructure, and improve the multiplying power performance of the negative electrode. Meanwhile, the three-dimensional conductive network is beneficial to reducing the accumulation of 'dead lithium' in the negative electrode and reducing the cycle capacity loss of the negative electrode. Is one of the most feasible technical schemes acknowledged in the metal lithium battery industry at present. For example, Cui et al, uses silicon-coated carbon foam having a three-dimensional structure as a skeleton, in which metallic lithium is filled. The molten lithium metal preferentially alloys with the silicon to change the interface wetting into the structure to form the composite electrode.
In addition, such methods typically require complex fabrication processes and expensive nanofabrication methods to achieve electrode fabrication, and require processes that incorporate lithium metal packing or encapsulation into three-dimensional structures, presenting significant challenges to commercial production under the current state of the art.
Through the analysis and comparison of the prior art scheme, the method can find that the metallic lithium negative electrode composite negative electrode with the three-dimensional structure is easy to prepare, the dendritic crystal inhibition effect of the metallic lithium in the negative electrode circulation process can be realized, and the method is the key for the metallic lithium battery to move towards practicality.
Disclosure of Invention
Therefore, the invention aims to provide a lithium metal alloy cathode material which has wide raw material sources, mild reaction conditions and simple preparation process, a preparation method thereof and a lithium ion battery which realizes high energy density and high safety by manufacturing the cathode material into a cathode.
The invention provides a lithium metal alloy negative electrode material which comprises a lithium alloy serving as a framework and metal lithium filled in the framework.
According to the negative electrode material provided by the invention, the lithium alloy is an alloy formed by metal lithium and one or more of Si, Sn, Al, Zn and Ca, and is preferably an alloy formed by metal lithium and one or more of Si, Sn, Al and Zn. Preferably, the lithium alloy is LiZn, Li9Al4、Li22Si5And Li17Sn4More preferably LiZn, Li22Si5And Li17Sn4One or more of (a).
According to the anode material provided by the invention, the molar ratio of lithium to metal lithium in the lithium alloy can be 1: 0.1 to 20, preferably 1:1 to 5.
According to the lithium metal alloy negative electrode material provided by the invention, the negative electrode material is a mixed binary or multi-element lithium metal alloy containing a metallic lithium phase and a lithium alloy phase (Li + LiX, x ═ Si, Sn, Zn, Ca, Al and the like, wherein Li is the metallic lithium phase, and LiX is the lithium alloy phase). Under normal use conditions, the electrochemical lithium removal potential difference between the lithium alloy phase and the metallic lithium phase is utilized to control the lithium removal reaction of the negative electrode, and the metallic lithium phase except the lithium alloy phase of the negative electrode can be used only to provide the circulating capacity. After all the metallic lithium is consumed, the lithium stored in the lithium alloy phase can be further used for compensating the capacity loss of the battery, and the cycle capacity is further provided.
The invention also provides a preparation method of the lithium metal alloy cathode material, which comprises the following steps:
(1) mixing metal lithium and an element simple substance alloyed with the lithium, and placing the mixture in a heat conduction container under inert atmosphere;
(2) heating the container until the metal lithium is melted, and stirring uniformly to carry out reaction.
According to the preparation method provided by the invention, the metallic lithium in the step (1) can be in any shape, such as block, sheet, strip, particle and wire, and the shape and size of the metallic lithium do not influence the synthesis preparation result.
According to the preparation method provided by the invention, the elemental substance alloying with lithium in the step (1) can be in any shape, such as silicon powder (nanometer, micrometer or millimeter level), monocrystalline silicon piece, silicon block and the like, and the shape and particle size of metal do not influence the synthesis preparation result.
According to the preparation method provided by the invention, the ratio of the metallic lithium and the element simple substance alloyed with the lithium in the step (1) is more than the maximum electrochemical lithium intercalation amount of the metallic material. Preferably, the atomic ratio of the metallic lithium to the elemental substance alloying with lithium is 10-20: 1.
According to the preparation method provided by the invention, the heat conducting container in the step (1) can be any material which does not react with metallic lithium and elements alloyed with the metallic lithium in the range of room temperature to 260 ℃, and is not particularly specified to be a container made of metal or other materials.
According to the production method provided by the present invention, the inert atmosphere in the step (1) may be any gas that does not react with metallic lithium and an element that is alloyed with metallic lithium in a range of room temperature to 260 ℃, such as argon, helium, and the like.
According to the preparation method provided by the invention, the stirring mode used in the step (2) can be any manual or mechanical stirring mode.
According to the preparation method provided by the invention, in order to fully perform the alloying reaction, the heating temperature in the step (2) can be 180-260 ℃, preferably 200-260 ℃, and the stirring time can be 20-60 minutes, preferably 30-40 minutes.
The invention also provides a lithium ion battery cathode, which comprises a cathode current collector and a cathode material loaded on the cathode current collector, wherein the cathode material is the lithium metal alloy cathode material provided by the invention or the lithium metal alloy cathode material prepared by the method.
According to the negative electrode provided by the invention, the current collector can be a sheet made of any metal which does not react with metallic lithium and has a thickness of 20-200 microns, and the metal used can be iron, titanium or zirconium, and is preferably iron.
The invention also provides a preparation method of the lithium ion battery cathode, which comprises the following steps:
(1) mixing metal lithium and an element simple substance alloyed with the lithium, and placing the mixture in a heat conduction container under inert atmosphere;
(2) heating the container until the metal lithium is melted, and stirring the mixture until the mixture is uniformly mixed;
(3) and (3) uniformly coating the liquid mixture prepared in the step (2) on the surface of the current collector, and then carrying out cooling treatment.
According to the preparation method of the negative electrode provided by the invention, the coating in the step (3) can adopt manual coating, mechanical coating or spraying, and the coating type is not limited.
According to the preparation method of the negative electrode provided by the invention, the cooling speed in the step (3) is more than 5 ℃/s, preferably more than 20 ℃/s, and more preferably more than 50 ℃/s.
The invention also provides a lithium ion battery, which comprises a battery shell, an electrode group and electrolyte, wherein the electrode group and the electrolyte are sealed in the battery shell, the electrode group comprises a positive electrode, a diaphragm and a negative electrode, and the negative electrode is the negative electrode of the lithium ion battery provided by the invention.
The lithium metal alloy cathode material and the preparation method and application thereof provided by the invention have the following advantages:
1. the traditional three-dimensional structure metal lithium negative electrode uses materials which are not alloyed with metal lithium, such as carbon, copper, nickel and the like, only can be structurally supported and electronically conducted in the negative electrode, and has no effect on improving the ionic conductivity in the negative electrode material. The lithium alloy has lithium ion conductivity, and compared with the traditional three-dimensional structure only having electronic conductivity, a better three-dimensional ion and electronic conductivity network can be formed, so that metal lithium is uniformly deposited, and lithium dendrites can not be generated even if the metal lithium is charged and discharged under the condition of extremely high current density, and obvious battery polarization phase is not generated.
2. The traditional three-dimensional structure metal lithium negative electrode uses materials which are not alloyed with metal lithium, such as carbon, copper, nickel and the like as a framework. When filling the metal lithium, the metal lithium can be packaged into the structure by a melting method by adopting low-yield electrochemical lithium intercalation or modifying the interface of the hollow structure to change the interface wettability. In the invention, the lithium metal alloy cathode structure with a three-dimensional structure can be formed by adopting a simple hot-melting alloy method and quick cooling.
3. Because the lithium alloy material capable of releasing and inserting lithium is adopted as the structural framework, the alloy framework can further release the capacity after the metallic lithium is consumed in the circulation process, and the circulation performance of the battery is ensured.
4. The raw materials used by the invention have wide sources and low price, and the process is simple and is suitable for rapid large-scale production.
Drawings
Embodiments of the invention are described in detail below with reference to the attached drawing figures, wherein:
fig. 1 is an XRD pattern of a lithium metal negative electrode containing lithium-silicon alloy prepared in example 2 of the present invention. Wherein the peaks marked by the hollow diamonds belong to Li22Si5And the four-pointed star marks belong to the metal lithium.
Fig. 2 is an SEM image of a lithium metal negative electrode containing a lithium-silicon alloy prepared in example 2 of the present invention.
Fig. 3 is an SEM image of a cross section of a lithium metal negative electrode containing lithium-silicon alloy prepared in example 2 of the present invention.
Fig. 4 is a plot of the energy spectrum (mapping) of the Si element for a cross section of a lithium metal negative electrode containing a lithium-silicon alloy prepared in example 2 of the present invention. It can be seen that the elemental silicon is relatively uniformly distributed in the material.
Fig. 5 is an SEM image of silicon remaining after complete delithiation of a lithium metal negative electrode containing a lithium-silicon alloy prepared in example 2 of the present invention. The interconnection between the silicon particles can be clearly seen and a loose porous structure is formed.
Fig. 6 is a graph showing the change in voltage when a metallic lithium negative electrode containing a lithium-silicon alloy prepared in example 2 of the present invention was charged to 1.5V as a positive electrode at a current of 10 mA. Wherein 0.4V or less represents a process of lithium deintercalation from metal, and 0.4V or more represents a process of lithium deintercalation from the lithium silicon alloy.
Fig. 7 is a graph showing the voltage change during repeated charge and discharge cycles of a lithium metal negative electrode containing a lithium-silicon alloy prepared in example 2 of the present invention as a positive electrode with a current of 10 mA.
Fig. 8 is a graph showing the voltage change during repeated charge and discharge cycles of a current of 5mA as the positive electrode for the lithium metal negative electrode not containing a lithium silicon alloy prepared in comparative example 1.
Detailed Description
The present invention is described in further detail below with reference to specific embodiments, which are given for the purpose of illustration only and are not intended to limit the scope of the invention.
Example 1
This example is intended to illustrate the preparation of a lithium metal alloy negative electrode according to the invention.
(1) Weighing 0.7g of metal lithium sheet and 0.28g of monocrystalline silicon sheet, placing in a glove box filled with argon gas, and placing in a container which does not react with lithium and silicon;
(2) heating the container to 200 ℃, completely melting the metal lithium, and contacting with silicon to perform an alloying reaction; stirring the liquid alloy for 30 minutes to uniformly mix the liquid alloy;
(3) coating the mixture on an iron foil current collector with a thickness of 100 μm; cooling to room temperature at a rate of 80 ℃/s to obtain the alloy (Li) containing metallic lithium and lithium silicon58+Li22Si5) The negative electrode of (2) is denoted as A1.
Example 2
A negative electrode was fabricated by substantially the same method as in example 1, except that 0.28g of the single-crystal silicon wafer was replaced with 0.28g of the nano-silicon powder in step (1), to obtain an alloy containing metallic lithium and lithium silicon (Li)58+Li22Si5) The negative electrode of (2) is denoted as A2.
Example 3
A negative electrode was produced in substantially the same manner as in example 1, except that 1.12g of tin powder was used in place of 0.28g of the single-crystal silicon wafer in step (1), to obtain a lithium-tin alloy (Li) containing metallic lithium and lithium58+Li17Sn4) The negative electrode of (2) is denoted as A3.
Example 4
A negative electrode was produced in substantially the same manner as in example 1, except that 0.28g of the single-crystal silicon wafer was replaced with 1.12g of a tin ingot in step (1), to obtain a lithium-tin alloy (Li) containing metallic lithium and lithium58+Li17Sn4) The negative electrode of (2) is denoted as A4.
Example 5
A negative electrode was produced in the same manner as in example 1 except that 0.28g of the single-crystal silicon wafer was replaced with 0.48g of aluminum powder in step (1), to obtain a lithium-containing alloy (Li) containing metallic lithium and lithium aluminum58+Li9Al4) The negative electrode of (2) is denoted as A5.
Example 6
A negative electrode was produced in the same manner as in example 1 except that 0.48g of a metallic aluminum block was used in place of 0.28g of the single-crystal silicon wafer in step (1), to obtain an alloy containing metallic lithium and lithium aluminum (Li)58+Li9Al4) The negative electrode of (2) is denoted as A6.
Example 7
A negative electrode was produced in the same manner as in example 1 except that 2.62g of zinc powder was used in place of 0.28g of the single-crystal silicon wafer in step (1), to obtain a negative electrode comprising metallic lithium and a lithium-zinc alloy (Li)58+ LiZn) as A7.
Example 8
A negative electrode was produced in substantially the same manner as in example 1, except that in step (1), 2.62g of a zinc sheet was used in place of 0.28g of the single-crystal silicon wafer, to obtain a lithium-zinc alloy (Li) containing metallic lithium and lithium58+ LiZn) as A8.
Example 9
A negative electrode was produced in the same manner as in example 1 except that 0.51g of the single-crystal silicon wafer was used in place of 0.28g of the single-crystal silicon wafer in step (1), to obtain an alloy containing metallic lithium and lithium silicon (Li)58+Li22Si5) The negative electrode of (2) is denoted as A9.
Example 10
A negative electrode was produced in the same manner as in example 1 except that 0.127g of the single-crystal silicon wafer was used in place of the 0.28g of the single-crystal silicon wafer in step (1), to obtain an alloy containing metallic lithium and lithium silicon (Li)58+Li22Si5) The negative electrode of (2) is denoted as A10.
Example 11
A negative electrode was produced in substantially the same manner as in example 1, except that in step (1), 2.23g of tin powder was used in place of 0.28g of the single-crystal silicon wafer, to obtain a lithium-tin alloy (Li) containing metallic lithium and lithium58+Li17Sn4) The negative electrode of (2) is denoted as A11.
Example 12
A negative electrode was produced in substantially the same manner as in example 1, except that 0.56g of tin powder was used in place of 0.28g of the single-crystal silicon wafer in step (1), to obtain a lithium-tin alloy (Li) containing metallic lithium and lithium58+Li17Sn4) The negative electrode of (2) is denoted as A12.
Example 13
A negative electrode was produced in substantially the same manner as in example 1, except that 0.28g of the single-crystal silicon wafer was replaced with 0.48g of aluminum powder in step (1) and the heating temperature in step (2) was 180 ℃ to obtain a lithium-aluminum alloy (Li) containing metallic lithium58+Li9Al4) The negative electrode of (2) is denoted as A13.
Example 14
A negative electrode was produced in substantially the same manner as in example 1, except that 0.28g of the single-crystal silicon wafer was replaced with 0.48g of aluminum powder in step (1) and the heating temperature in step (2) was 300 ℃ to obtain a lithium-aluminum alloy (Li) containing metallic lithium58+Li9Al4) The negative electrode of (2) is denoted as A14.
Example 15
A negative electrode was produced in the same manner as in example 1 except that 2.62g of zinc powder was used in place of 0.28g of the single-crystal silicon wafer in step (1) and the heating temperature in step (2) was 180 ℃ to obtain a negative electrode comprising metallic lithium and a lithium-zinc alloy (Li)58+ LiZn) as A15.
Example 16
A negative electrode was produced in the same manner as in example 1 except that 2.62g of zinc powder was used in place of 0.28g of the single-crystal silicon wafer in step (1) and the heating temperature in step (2) was 300 ℃ to obtain a negative electrode comprising metallic lithium and a lithium-zinc alloy (Li)58+ LiZn) as A16.
Example 17
A negative electrode was produced in the same manner as in example 1 except that 0.28g of the single-crystal silicon wafer was replaced with 0.48g of aluminum powder in step (1) and that the glass rod was manually stirred for 30 minutes in step (2)Obtaining an alloy containing metallic lithium and lithium aluminum (Li)58+Li9Al4) The negative electrode of (2) is denoted as A17.
Example 18
A negative electrode was fabricated in substantially the same manner as in example 1, except that 0.28g of the single-crystal silicon wafer was replaced with 0.48g of aluminum powder in step (1) and mechanical automatic stirring was performed for 30 minutes in step (2), to obtain a lithium-aluminum alloy (Li) containing metallic lithium and lithium58+Li9Al4) The negative electrode of (2) is denoted as A18.
Example 19
An anode was prepared in substantially the same manner as in example 1, except that in step (3), the temperature was lowered to room temperature at a rate of 20 ℃/s, and was designated as A19.
Example 20
An anode was prepared in substantially the same manner as in example 1, except that in step (3), the temperature was lowered to room temperature at a rate of 50 ℃/s, and was designated as A20.
Example 21
A negative electrode was fabricated in substantially the same manner as in example 3, except that the temperature was lowered to room temperature at a rate of 20 ℃/s in step (3), to obtain a lithium-tin alloy (Li) containing metallic lithium and lithium58+Li17Sn4) The negative electrode of (2) is denoted as A21.
Example 22
A negative electrode was fabricated in substantially the same manner as in example 3, except that the temperature was lowered to room temperature at a rate of 50 ℃/s in step (3), to obtain a lithium-tin alloy (Li) containing metallic lithium and lithium58+Li17Sn4) The negative electrode of (2) is denoted as A22.
Example 23
A negative electrode was fabricated in substantially the same manner as in example 7, except that the temperature was lowered to room temperature at a rate of 20 ℃/s in step (3), to obtain a lithium-zinc alloy (Li) containing metallic lithium and lithium58+ LiZn) as A23.
Examples24
A negative electrode was fabricated in substantially the same manner as in example 7, except that the temperature was lowered to room temperature at a rate of 50 ℃/s in step (3), to obtain a lithium-zinc alloy (Li) containing metallic lithium and lithium58+ LiZn) as A24.
Comparative example 1
(1) Weighing 0.7g of metal lithium sheet in a glove box filled with argon, and placing the metal lithium sheet in a container which does not react with lithium;
(2) heating the container to 200 ℃, and completely melting the metal lithium; stirring liquid metal lithium for 30 minutes;
(3) coating liquid metal lithium on an iron foil current collector with the thickness of 100 mu m; the temperature was reduced to room temperature at a rate of 80 ℃/s to obtain a negative electrode containing only metallic lithium, designated B1.
The alloy negative electrodes prepared in the above examples and comparative examples and commercial lithium metal wafers were used as positive and negative electrodes, respectively, and the EC of 1M: DMC 1:1 is an electrolyte and CR2032 button cells are assembled in a glove box using PP/PE/PP separators from Celgard, usa. The battery is subjected to charge and discharge tests, and the surface current density is 20mAcm-2The current is charged and discharged in a constant current mode for 1 hour, a cycle is formed, the change of the voltage of the battery is recorded, and the fluctuation condition of the battery is observed; the cell after 3000 hours of cycling was disassembled and the surface was observed for lithium dendrite growth and the results are shown in table 1.
TABLE 1
Figure BDA0001568948930000111
Figure BDA0001568948930000121
As can be seen from the indices of examples 1 to 8 and comparative example 1 in table 1, the negative electrode having a lithium metal alloy skeleton maintains a voltage more stably during cycling and does not generate dendrites than the simple metal lithium. And the negative electrode taking Si, Zn, Sn, Al and other alloys as the framework has obvious effects, and the improvement effect is independent of the size and the shape of the used raw materials.
As can be seen from the comparison of the indices of examples 9-12 in table 1, the different content of metallic lithium in the composite negative electrode has an effect on the battery cycle: the effect is best when the content of the metal lithium is about 60 percent, and when the content of the metal lithium is too small (20 percent), lithium in the alloy can be extracted, so that the voltage is unstable; too much (80%) does not exert the regulating effect of the alloy skeleton on lithium deposition, and dendrite generation still occurs.
As can be seen from the comparison of the indices of examples 13-16 in table 1, different heating temperatures also have an effect on the battery cycle: when the heating temperature is too low, the raw materials cannot be alloyed fully, a three-dimensional structure cannot be formed, and dendritic crystals are still generated.
As can be seen from the comparison of the indices of examples 17-18 in Table 1, the different stirring modes have no effect on the performance of the negative electrode in cycling.
As can be seen from the comparison of the indices of examples 19-24 in table 1, the different ramp rates have a slight effect on the performance of the negative electrode during cycling: the faster the temperature drop rate, the more stable the battery cycling voltage.

Claims (10)

1. The lithium metal alloy negative electrode material for the lithium ion battery comprises a lithium alloy serving as a framework and metal lithium filled in the framework, wherein the molar ratio of the lithium in the lithium alloy to the metal lithium is 1: 1-5, and the lithium alloy is LiZn or Li9Al4、Li22Si5And Li17Sn4One or more of (a) or (b),
the preparation method of the lithium metal alloy negative electrode material comprises the following steps:
(1) mixing metal lithium and an element simple substance alloyed with the lithium, and placing the mixture in a heat conduction container under inert atmosphere;
(2) heating the vessel until the lithium metal melts, stirring the mixture until uniform mixing, and then cooling at a rate greater than 20 ℃/s.
2. The anode material according to claim 1, wherein the lithium alloy is LiZn, Li22Si5And Li17Sn4One or more of (a).
3. The method for preparing a lithium metal alloy anode material according to claim 1 or 2, comprising the steps of:
(1) mixing metal lithium and an element simple substance alloyed with the lithium, and placing the mixture in a heat conduction container under inert atmosphere;
(2) heating the vessel until the lithium metal melts, stirring the mixture until uniform mixing, and then cooling at a rate greater than 20 ℃/s.
4. The preparation method according to claim 3, wherein the atomic ratio of the metallic lithium to the elemental substance alloying with lithium in the step (1) is 10 to 20: 1.
5. The method according to claim 3, wherein the heating temperature in the step (2) is 180 to 260 ℃ and the stirring time in the step (2) is 20 to 60 minutes.
6. The method according to claim 5, wherein the heating temperature in the step (2) is 200 to 260 ℃ and the stirring time is 30 to 40 minutes.
7. A negative electrode of a lithium ion battery, comprising a negative electrode current collector and a negative electrode material loaded on the negative electrode current collector, wherein the negative electrode material is the lithium metal alloy negative electrode material of claim 1 or 2 or the lithium metal alloy negative electrode material prepared by the method of any one of claims 3 to 6.
8. A preparation method of a lithium ion battery negative electrode comprises the following steps:
(1) mixing metal lithium and an element simple substance alloyed with the lithium, and placing the mixture in a heat conduction container under inert atmosphere;
(2) heating the container until the metal lithium is melted, and stirring the mixture until the mixture is uniformly mixed;
(3) uniformly coating the liquid mixture prepared in the step (2) on the surface of a current collector, cooling at the speed of more than 20 ℃/s,
wherein, the lithium alloy formed by metallic lithium and the element simple substance alloyed with the lithium is LiZn and Li9Al4、Li22Si5And Li17Sn4The molar ratio of alloyed lithium to unalloyed lithium metal is 1: 1-5.
9. The method according to claim 8, wherein the cooling rate in the step (3) is more than 50 ℃/s.
10. A lithium ion battery comprising a battery case, an electrode assembly and an electrolyte, the electrode assembly and the electrolyte being sealed in the battery case, the electrode assembly comprising a positive electrode, a separator and a negative electrode, wherein the negative electrode is the negative electrode of claim 7 or the negative electrode produced by the method of claim 8 or 9.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1110721A (en) * 1994-04-25 1995-10-25 北京有色金属研究总院 Lithium-aluminium alloy as cell's negative pole material and its manufacture method
CN1929165A (en) * 2005-09-09 2007-03-14 比亚迪股份有限公司 Battery negative electrode and lithium secondary battery having same
CN104810511A (en) * 2015-04-10 2015-07-29 苏州靖羽新材料有限公司 Anode material of electrical equipment and electrical equipment
CN106486644A (en) * 2016-11-19 2017-03-08 天津赫维科技有限公司 A kind of preparation method of Li-Si alloy negative pole

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100953543B1 (en) * 2003-12-01 2010-04-21 삼성에스디아이 주식회사 Lithium anode, process for preparing the same and lithium battery using the same
WO2011066518A1 (en) * 2009-11-30 2011-06-03 Oc Oerlikon Balzers Ag Lithium ion battery and method for manufacturing of such battery
CN103290293B (en) * 2013-06-05 2016-02-24 四川天齐锂业股份有限公司 Lithium-aluminium alloy and production method thereof and purposes
CN104466232A (en) * 2013-09-24 2015-03-25 华为技术有限公司 Lithium-ion battery and preparation method of lithium metal alloy

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1110721A (en) * 1994-04-25 1995-10-25 北京有色金属研究总院 Lithium-aluminium alloy as cell's negative pole material and its manufacture method
CN1929165A (en) * 2005-09-09 2007-03-14 比亚迪股份有限公司 Battery negative electrode and lithium secondary battery having same
CN104810511A (en) * 2015-04-10 2015-07-29 苏州靖羽新材料有限公司 Anode material of electrical equipment and electrical equipment
CN106486644A (en) * 2016-11-19 2017-03-08 天津赫维科技有限公司 A kind of preparation method of Li-Si alloy negative pole

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