CN111613773B - Composite of glass fiber with hierarchical structure and metallic lithium and preparation method thereof - Google Patents
Composite of glass fiber with hierarchical structure and metallic lithium and preparation method thereof Download PDFInfo
- Publication number
- CN111613773B CN111613773B CN202010318876.6A CN202010318876A CN111613773B CN 111613773 B CN111613773 B CN 111613773B CN 202010318876 A CN202010318876 A CN 202010318876A CN 111613773 B CN111613773 B CN 111613773B
- Authority
- CN
- China
- Prior art keywords
- glass fiber
- lithium
- layer
- metal
- thickness
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
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
- 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
- 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
-
- 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
- H01M4/624—Electric conductive fillers
- H01M4/626—Metals
-
- 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
- H01M2004/026—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
Abstract
The invention discloses a composite of glass fiber and metal lithium in a hierarchical structure and a preparation method thereof, and relates to the technical field of battery cathodes. The deposited lithium ions can only obtain electrons on the glass fiber with the modification layer on the surface of the composite electrode, and can not obtain electrons at the top end of the glass fiber, so that lithium dendrite and dead lithium exceeding the thickness of the glass fiber on the surface can not be formed, the total thickness of the electrode can be controlled, and the safety of the battery is high. The topmost surface of the glass fiber is electrically insulated, and the battery is not short-circuited after the diaphragm is attached to the battery. The lithium metal on the lower half part of the glass fiber is responsible for supplementing a lithium source, and the cycle performance of the battery is guaranteed.
Description
Technical Field
The invention relates to the technical field of lithium battery cathodes, in particular to a composite of glass fiber and metallic lithium with a hierarchical structure and a preparation method thereof.
Background
Compared with the graphite cathode commercially applied to the lithium ion battery at present, the lithium metal cathode can theoretically provide more capacity (3860mAh/g, graphite cathode: 372mAh/g) and most negative potential (-3.040V vs. standard hydrogen electrode), and is expected to realize larger application in the fields of next-generation portable electronic equipment, electric automobiles and the like. Lithium-sulfur batteries and lithium-air batteries using lithium metal as a negative electrode have attracted attention of researchers, and have become a focus of academic and industrial research in recent years. However, many problems still exist in the study of lithium metal negative electrodes, the most important one of which is the growth of dendrites. Dendrites are dendritic lithium deposits that occur in the negative electrode during multiple deposition/precipitation of lithium ions in the negative electrode.
Dendrite growth can cause three problems: (1) the dendrite can pierce through the diaphragm to cause short circuit of the battery, and short-circuit current in the positive electrode and the negative electrode generates heat in the battery to cause thermal runaway of a battery system, so that a series of safety problems of ignition and even explosion of the battery are caused; (2) the dendrite can increase the side reaction of the electrolyte and the lithium metal, consume lithium active substances and reduce the utilization rate of the battery; (3) during deposition/stripping of lithium, there is a large volume deformation for thin metal lithium cathodes, which places the battery cathode as a whole in an uncontrolled dynamic variation, which can result in a reduction in battery cycling capability.
Specifically, when the positive electrode material contains lithium ions, the negative electrode metal lithium serves only as a supplementary lithium source, and no intercalation or solid solution process occurs as in the negative electrode of a lithium ion battery. However, lithium dendrites are still generated at the uneven positions on the surface of the metal lithium and at the uneven positions of concentration caused by the free diffusion of the electrolyte; in the subsequent dissolving process, because the root of the lithium dendrite is close to the current collector, electrons are lost more quickly to become lithium ions (namely, the lithium ions are dissolved more quickly), so that the upper part of the lithium dendrite is gradually separated from the charge transfer channel to generate dead lithium. Consuming electrolyte and destroying SEI film.
In order to suppress dendrite growth and improve the safety, utilization and cycle life of lithium metal batteries, scientists have proposed a variety of solutions based on lithium negative electrode frameworks in the past half century, mainly including both the construction of the lithium metal surface framework and the construction of the lithium metal internal framework.
For example, chinese patent CN105845891A discloses a method for constructing an ex-situ (artificial) solid electrolyte interface film on the surface of lithium. The metal lithium negative electrode is composed of a metal lithium layer at the bottom layer and a surface covering layer at the upper layer, wherein the surface covering layer is one or more of carbon materials, polymer materials and glass fibers. The lithium metal negative electrode keeps no dendritic crystal in the lithium metal negative electrode in 20-5000 times of battery cycles; the lithium metal negative electrode can improve the utilization rate of the lithium metal negative electrode to more than 80%.
For example, the method for preparing a composite lithium metal negative electrode proposed in chinese patent CN108365200A can realize efficient compounding of various common framework materials (including conductive framework materials and insulating framework materials) with liquid metal lithium after modification, so as to obtain a composite lithium metal negative electrode material containing preset high-purity metal lithium. When the obtained composite lithium metal battery negative electrode material is assembled in a lithium metal full battery, the growth of lithium dendrite can be effectively inhibited, the pulverization phenomenon of a lithium metal negative electrode is reduced, and the cycle stability, safety and cycle life of the lithium metal battery are greatly improved.
The composite lithium metal negative electrode disclosed in chinese patent CN108281612A comprises lithium metal and a functional three-dimensional skeleton, wherein the functional three-dimensional skeleton is formed by mutually inserting and interweaving skeleton pieces to form a structure with a gap or a cavity, and the gap or the cavity is filled with lithium metal; the thickness of the functional three-dimensional skeleton is 1 nm-500 mu m. According to the composite lithium metal cathode prepared by the invention, the functional group structure rich on the surface of the functional three-dimensional skeleton can well identify and combine lithium ions and anions specifically in the three-dimensional space of the cathode, so that the balance of the lithium ions and the anions at the interface is realized, the ion concentration gradient driven by an electric field is prevented, the effect of effectively adjusting the distribution of the cathode ions in the repeated charge and discharge process is achieved, the growth without dendrites at the interface can be realized, and the coulomb efficiency, the safety and the cycle life of the lithium metal cathode are effectively improved.
The above methods provide many ideas for the suppression of dendrites and dead lithium, but the growth suppression of lithium dendrites is still of limited effect. Because (1) the surface of the negative electrode subjected to bulk three-dimensional framework modification does not have a space to accommodate the deposition of a metallic lithium layer when lithium ions of the counter electrode are deposited on the negative electrode, lithium dendrites can preferentially nucleate on the lithium surface, especially at high current densities; even if there is some space, preferential deposition may be performed at a specific site on the lithium surface, such as a skeleton site, in a later step during the deposition process, and uniform deposition may not be continued. (2) The negative electrode is modified by a surface three-dimensional framework, the three-dimensional framework of the negative electrode does not have a hierarchical structure, when the three-dimensional framework is a non-electronic conductor, lithium ions need to penetrate through the framework to reach the surface of metal lithium, and the diffusion path is long, so that the exchange current density of the surface of the electrode is low, the polarization is large, and non-uniform deposition is easy to form; when the three-dimensional framework is an electronic conductor, the metal lithium has no preferential nucleation tendency, and the preferential deposition is possibly carried out on the surface of the three-dimensional framework to form lithium dendrites.
However, if a material with a special hierarchical structure and stronger interaction with lithium ions can be used, an artificial SEI and a framework structure are simultaneously constructed in a surface layer and a bulk phase of the metallic lithium negative electrode, so that the stability of the metallic lithium negative electrode in the operation process is effectively improved, the capability of inhibiting the growth of lithium dendrites is greatly required for improving the safety performance of a lithium metal battery of the battery. Further coupled with a positive electrode material with high specific capacity, such as a high nickel positive electrode, sulfur and the like, has important significance for constructing a lithium secondary battery system with high energy density, high stability and high safety.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a composition of glass fiber with a hierarchical structure and metallic lithium, wherein the glass fiber is in a hierarchical structure of 'upper surface-middle lower surface', the glass fiber is used as a framework material of the metallic lithium, and part of the glass fiber is exposed on the surface of the metallic lithium, so that an artificial SEI and a framework can be simultaneously constructed in the surface layer and the bulk phase of the metallic lithium cathode, the stability of the metallic lithium cathode in the operation process can be effectively improved, and the capability of inhibiting the growth of lithium dendritic crystals can be effectively improved.
In order to realize the purpose, the invention provides the following technical scheme:
the utility model provides a hierarchical structure glass fiber and lithium metal's compound, includes the lithium layer, be provided with the glass fiber layer in the lithium layer, the bottom of glass fiber layer is wrapped up in the lithium layer completely, the top exposes in the outside on lithium layer, glass fiber middle and lower surface is provided with the conducting layer, the upper end is naked state, the conducting layer has lithium affinity and electron conductivity, the naked top of glass fiber layer does not have electron or ion conductivity.
By adopting the technical scheme, the glass fiber three-dimensional carrier which is electronically conductive and not alloyed with the metal lithium is constructed in the metal lithium and on the surface of the metal lithium, and the top end surface of the glass fiber is electronically and ionically insulated. Therefore, the deposited lithium ions can only obtain electrons on the glass fiber with the modification layer on the surface of the composite electrode, and can not obtain electrons at the top end of the glass fiber, so that lithium dendrite and dead lithium exceeding the thickness of the surface glass fiber can not be formed, the total thickness of the electrode can be controlled, and the safety of the battery is high. The topmost surface of the glass fiber is electrically insulated, and the battery is not short-circuited after the diaphragm is attached to the battery. The lithium metal on the lower half part of the glass fiber is responsible for supplementing a lithium source, and the cycle performance of the battery is guaranteed.
Further, the conducting layer is made of one or more of lithium-philic metal materials and poly (3, 4-ethylenedioxythiophene).
By adopting the technical scheme, the conducting layer can be prepared by various processes, so that the diversity of the scheme is improved, and the conducting layer can be conveniently prepared by workers.
Further, the glass fiber is a woven glass fiber fabric.
By adopting the technical scheme, the single glass fiber has small size, but the braided fabric has thickness in the depth direction and area in the plane, and a large number of pores formed by the fiber are arranged in the braided fabric. Therefore, the glass fiber can be roughly divided into an upper surface, a middle surface and a lower surface, so that the glass fiber is conveniently and uniformly shielded, and the glass fiber is ensured to have a uniform hierarchical structure.
Further, the glass fibers have an electrical conductivity less than10-8S/cm。
By adopting the technical scheme, the insulating property of the glass fiber is ensured.
Further, the exposed thickness of the upper end of the glass fiber layer is 5-30 μm, and the exposed thickness is (positive electrode surface capacity 5+ (0-5)) μm.
By adopting the technical scheme, the positive pole piece can lead Li in self crystal lattice to be absorbed in the charging process+After passing through the diaphragm and the electrolyte, the lithium is deposited on the surface of the negative electrode to form simple substance lithium. The higher the surface capacity of the positive electrode is, the thicker the lithium deposited on the surface of the negative electrode is, and the thickness of the glass fiber on the surface of the negative electrode must be determined by the surface capacity of the positive electrode in order to fully contain the newly deposited lithium simple substance. If the thickness is too large, the whole battery is too thick, and the volume energy density of the battery is reduced; too thin may not fully accommodate the deposited lithium species, and therefore the optimum value is (positive electrode surface capacity 5+ (0 to 5)) μm.
Further, the thickness of the lithium layer is 10-100 μm, and the thickness of the lithium layer is (positive electrode face capacity (1-coulombic efficiency) 5+ expected cycle number + (0-10)) μm.
By adopting the technical scheme, the thickness of the lower half part of the glass fiber is determined by the thickness of the lithium layer, and in the discharging process, the lithium simple substance on the negative electrode loses electrons to become movable Li+And after passing through the diaphragm and the electrolyte, the lithium ion battery returns to the crystal lattice of the positive electrode material, and in the process, 100% of lithium from the positive electrode cannot return to the positive electrode, so that a part of the positive electrode needs to be replenished in order to ensure that the coulombic efficiency reaches an optimal value. Then the lower half of the glass fiber can be used for the lithium layer as a supplement. The higher the number of cycles required, the more predetermined lithium is required to replenish, and thus the thickness of the lower half of the glass fiber. And the glass fiber has the function of reinforcing steel bars in reinforced concrete, so that the mechanical strength and the integrity of the whole system are improved.
Another object of the present invention is to provide a method for preparing the composite of glass fiber with hierarchical structure and metallic lithium, comprising the following steps:
s1, adhering the upper surfaces of the glass fibers by using an adhesive tape, adding a conductive layer to the middle and lower surfaces of the glass fibers by at least one of sputtering, spraying, liquid-phase chemical deposition, vapor-phase chemical deposition, chemical plating and electroplating, and tearing off the corresponding adhesive tape to obtain graded glass fibers;
s2, melting the metal lithium, inserting the graded glass fiber into the molten metal lithium, and then solidifying and forming;
s3, placing the above compound into a sealed bag and performing isostatic pressing operation to press the lithium metal into the graded glass fiber.
Through adopting above-mentioned technical scheme, the mode of sticking to glass fiber through the sticky tape shelters from glass fiber, and easy operation is convenient, and shelters from effectually. After the glass fiber is inserted into the molten metal lithium for solidification, because the glass fiber contains a large number of pores formed in a staggered way, the metal lithium can not be completely attached to the glass fiber, the method for forming the dense blank from the barren powder by the method is called isostatic pressing, so that the metallic lithium can be completely embedded into the graded glass fiber, and the connectivity and stability of the composition are improved.
Further, in step S1, the inverted glass fiber is sputtered from top to bottom using a sputtering apparatus to complete the plating of the middle and lower surfaces of the glass fiber.
By adopting the technical scheme, the metal such as gold, silver, zinc, aluminum, copper and the like can be attached to the surface of the glass fiber to form the conductive layer by adopting a sputtering mode.
Further, in step S1, the glass fiber is sprayed with an aqueous solution of poly (3, 4-ethylenedioxythiophene), bonded to the unmasked surface of the glass fiber, dried, and attached to the surface of the glass fiber to form a conductive layer.
By adopting the technical scheme, the water solution of the poly (3, 4-ethylenedioxythiophene) can be directly sprayed on the surface of the glass fiber in a spraying mode, and can be firmly combined on the surface of the glass fiber after being dried.
Further, in step S1, the glass fibers are treated with a solution of palladium chloride and tin dichloride to form palladium metal on the unmasked surfaces of the glass fibers, and then the plated metal layer is electroplated to form the conductive layer.
By adopting the technical scheme, the transition metal can be electroplated on the surface of the glass fiber.
In conclusion, the invention has the following beneficial effects:
1. the invention constructs a glass fiber three-dimensional carrier which has electronic conductivity and is not alloyed with the metal lithium in the metal lithium and on the surface of the metal lithium, and the top surface of the glass fiber is electronically and ionically insulated. Therefore, the deposited lithium ions can only obtain electrons from the glass fiber of the modification layer on the surface of the composite electrode, and can not obtain electrons from the top end of the glass fiber, so that lithium dendrite and dead lithium exceeding the thickness of the glass fiber on the surface can not be formed, the total thickness of the electrode is controllable, and the safety of the battery is high. The surface of the glass fiber is electrically insulated, and the battery can not be short-circuited after the diaphragm is attached to the battery. The metal lithium on the lower half part of the glass fiber is responsible for supplementing a lithium source, and the cycle performance of the battery is guaranteed;
2. the conducting layer can be prepared by various processes, so that the diversity of the scheme is improved, and the conducting layer can be conveniently prepared by workers;
3. the thickness of the lower half part of the glass fiber is determined by the thickness of the lithium layer, and during the discharge process, the lithium on the negative electrode loses electrons to become movable Li+And after passing through the diaphragm and the electrolyte, the lithium ion battery returns to the crystal lattice of the positive electrode material, and in the process, 100% of lithium from the positive electrode cannot return to the positive electrode, so that a part of the positive electrode needs to be replenished in order to ensure that the coulombic efficiency reaches an optimal value. Then, at this time, the lithium layer of the lower half of the glass fiberIt can be used for supplementary purposes. The higher the number of cycles required, the more predetermined lithium is required to replenish, and thus the thickness of the lower half of the glass fiber. The glass fiber has the function of reinforcing steel bars in reinforced concrete, so that the mechanical strength and integrity of the whole system are improved;
4. the glass fiber is masked in a mode that the glass fiber is stuck by the adhesive tape, the operation is simple and convenient, and the masking effect is good. After the glass fiber is inserted into the molten metal lithium for solidification, because the glass fiber contains a large number of pores formed in a staggered manner, the metal lithium cannot be completely attached to the glass fiber, and through isostatic pressing operation, the metal lithium can be completely embedded into the graded glass fiber, so that the connectivity and the stability of the composition are improved.
Drawings
FIG. 1 is a schematic diagram of the structure of the composite of the present invention.
Reference numerals: 1. a lithium layer; 2. a glass fiber layer; 3. and a conductive layer.
Detailed Description
The present invention will be described in further detail with reference to the following drawings and examples.
Examples
Example 1
Referring to fig. 1, the composite of glass fiber and metallic lithium in a hierarchical structure includes a lithium layer 1 and a glass fiber layer 2, wherein the lower portion of the glass fiber layer 2 is inserted into the lithium layer 1, and the upper portion of the glass fiber layer 2 is exposed above the lithium layer 1. The glass fiber layer 2 is coated with a conductive layer 3 except for the top surface, the conductive layer 3 having lithium affinity and electron conductivity, and the glass fiber has a conductivity of less than 10-8S/cm, such that the bare tip of the glass fiber layer 2 has no electronic or ionic conductivity. Wherein, the glass fiber layer 2 adopts a glass fiber braided fabric.
The thickness of the glass fiber layer 2 inserted into the lithium layer 1 is the same as that of the lithium layer 1, the thickness of the lithium layer 1 is (positive electrode surface capacity (1-coulombic efficiency) 5+ expected cycle times (0 to 10)) mum, so that lithium of the lithium layer 1 preset at the lower part of the glass fiber layer 2 can be used for supplying a positive electrode, and the coulombic efficiency reaches an optimal value; the upper part of the glass fiber layer 2 is exposed above the lithium layer 1 to form a deposition layer, and the thickness of the deposition layer is (the capacity of the positive electrode surface is 5+ (0-5)) mum, so that the glass fiber on the surface of the negative electrode can completely contain the lithium simple substance newly deposited.
The preparation method of the composite of the glass fiber with the hierarchical structure and the metallic lithium comprises the following steps:
s1, adhering the upper surface of the glass fiber layer 2 by using an adhesive tape for masking, adding a conductive gold layer to the middle and lower surfaces of the glass fiber by a gold layer sputtering method to form a conductive layer 3, and tearing off the corresponding adhesive tape to obtain graded glass fiber;
s2, melting the metal lithium at 300 ℃, inserting the graded glass fiber into the molten metal lithium, and cooling and molding at room temperature;
s3, putting the compound into a sealed bag for isostatic pressing operation, and continuously pressing the lithium metal into the graded glass fiber;
and S4, obtaining the composite of the glass fiber with the hierarchical structure and the metallic lithium.
In the embodiment, the total thickness of the glass fiber layer 2 is 100 micrometers, the thickness of the gold layer sputtered on the middle and lower surfaces is 500nm, the total longitudinal depth of the glass fiber covered by sputtering is 99 micrometers, the thickness of the composite lithium layer 1 is 84 micrometers, the thickness of the exposed layer is 16 micrometers, 15 micrometers of the exposed layer is covered with the gold layer, and the top layer of 1 micrometer is not covered with gold.
Example 2
The difference from example 1 is that the method for preparing the composite of the hierarchical structure glass fiber and metallic lithium comprises the following steps:
s1, adhering the upper surface of the glass fiber layer 2 by using an adhesive tape for masking, spraying the glass fiber by using a water solution of poly (3, 4-ethylenedioxythiophene), combining with the unmasked surface of the glass fiber, drying, adhering to the surface of the glass fiber to form a conductive layer 3, and tearing off the adhesive tape;
s2, melting the metal lithium at 300 ℃, inserting the graded glass fiber into the molten metal lithium, and cooling and molding at room temperature;
s3, putting the compound into a sealed bag for isostatic pressing operation, and continuously pressing the lithium metal into the graded glass fiber;
and S4, obtaining the composite of the glass fiber with the hierarchical structure and the metallic lithium.
In the embodiment, the total thickness of the glass fiber layer 2 is 100 μm, the thickness of the poly (3, 4-ethylenedioxythiophene) covered on the middle and lower surfaces is 500nm, the total longitudinal depth of the glass fiber covered by the poly (3, 4-ethylenedioxythiophene) is 99 μm, the thickness of the composite lithium layer 1 is 20 μm, the thickness of the exposed layer is 80 μm, 79 μm of the exposed layer is covered by the poly (3, 4-ethylenedioxythiophene), and the top layer with the thickness of 1 μm is not covered by the poly (3, 4-ethylenedioxythiophene).
Example 3
The difference from example 1 is that the method for preparing the composite of the hierarchical structure glass fiber and metallic lithium comprises the following steps:
s1, adhering and masking the upper surface of the glass fiber layer 2 by using an adhesive tape, soaking the glass fiber by using a solution of palladium chloride and tin dichloride, combining palladium metal obtained by reaction with the unmasked surface of the glass fiber, and drying and attaching the palladium metal to the surface of the glass fiber to form a conductive layer;
s2, connecting the compound with a cathode for electroplating, and electroplating gold on the surface of the glass fiber to form a conductive layer 3;
s2, melting the metal lithium at 300 ℃, inserting the graded glass fiber into the molten metal lithium, and cooling and molding at room temperature;
s3, putting the compound into a sealed bag for isostatic pressing operation, and continuously pressing the lithium metal into the graded glass fiber;
and S4, obtaining the composite of the glass fiber with the hierarchical structure and the metallic lithium.
In the embodiment, the total thickness of the glass fiber layer 2 is 100 micrometers, the thickness of the palladium layer covered by the middle and lower surfaces is 5nm, the thickness of the gold layer is 500nm, the total longitudinal depth of the glass fiber covered by the gold layer is 99 micrometers, the thickness of the composite lithium layer 1 is 91 micrometers, the thickness of the exposed layer is 9 micrometers, namely, 8 micrometers of the exposed layer is gold, and the top layer of 1 micrometer is not covered with gold. The plating solution for electroplating gold is gold potassium sulfite, and the counter electrode is platinum.
Comparative example
Comparative example 1.
The difference from example 1 is that the conditions are the same as in the case where the patent publication No. CN108365200A is used for comparison and the thickness of the negative electrode lithium layer 1 is 100 μm.
Comparative example 2
The difference from example 1 is that the thickness of the lithium layer 1 was 100 μm and the thickness of the exposed layer was 0 μm.
Comparative example 3
The difference from example 1 is that the thickness of the lithium layer 1 was 90 μm and the thickness of the exposed layer was 10 μm.
Comparative example 4
The difference from example 1 is that the thickness of the lithium layer 1 was 50 μm and the thickness of the exposed layer was 50 μm.
Comparative example 5
The difference from example 1 is that the thickness of the lithium layer 1 was 10 μm and the thickness of the exposed layer was 90 μm.
Comparative example 6
The difference from example 1 is that the thickness of the lithium layer 1 was 0 μm and the thickness of the exposed layer was 100 μm.
TABLE 1 values for lithium metal layers and exposed layers
| Thickness of metallic lithium layer | Thickness of the deposited layer | |
| Example 1 | 84μm | 16μm |
| Example 2 | 20μm | 80μm |
| Example 3 | 91μm | 9μm |
| Comparative example 2 | 100μm | 0μm |
| Comparative example 3 | 90μm | 10μm |
| Comparative example 4 | 50μm | 50μm |
| Comparative example 5 | 10μm | 90μm |
| Comparative example 6 | 0μm | 100μm |
Battery assembly
And assembling the cathode and the lithium iron phosphate anode into a button cell for testing. The surface capacity of the lithium iron phosphate positive pole piece is 3 mAh/cm2The test temperature is (25 +/-2 ℃), the test system is 1C charge/1C discharge, the electrolyte is a 1M solution of LiTFSI in DOL/DME =1:1, the number of times of short circuit of the test battery or the number of times of short circuit until the retention rate is 80% are counted, and the statistical results are shown in Table 2.
TABLE 2 number of charge-discharge cycles
| Cycle number with retention of 80% | Number of cycles during short circuit of battery | |
| Example 1 | 497 | The retention rate is attenuated to zero and is not short-circuited |
| Example 2 | 99 | The retention rate is attenuated to zero and is not short-circuited |
| Example 3 | 504 | 719 |
| Comparative example 1 | 377 | 416 |
| Comparative example 2 | The battery capacity retention rate is 90 percent when the battery is circulated to 102 times of short circuit | 102 |
| Comparative example 3 | 458 | 529 |
| Comparative example 4 | 247 | The retention rate is attenuated to zero and is not short-circuited |
| Comparative example 5 | 44 | The retention rate is attenuated to zero and is not short-circuited |
| Comparative example 6 | 6 | The retention rate is attenuated to zero and is not short-circuited |
As can be seen from table 2, in the present invention, the glass fiber three-dimensional carrier having electron conductivity and not alloyed with the metal lithium is constructed in both the interior and the surface of the metal lithium, and the top surface of the glass fiber is electron-ion insulated, so that the deposited lithium ions can only obtain electrons from the glass fiber of the modification layer on the surface of the composite electrode, and cannot obtain electrons from the top of the glass fiber, so as to prevent formation of lithium dendrite and dead lithium exceeding the thickness of the glass fiber on the surface, thereby controlling the total thickness of the electrode and ensuring high battery safety. The topmost surface of the glass fiber is electrically insulated, and the battery is not short-circuited after the diaphragm is attached to the battery. The lithium layer 1 on the lower half part of the glass fiber layer 2 is responsible for supplementing a lithium source, and the cycle performance of the battery is guaranteed. When the exposed layer has a thickness of 5-30 μm, the exposed layer has a thickness of (positive electrode surface capacity 5+ (0-5)) μm, the metallic lithium layer 1 has a thickness of 10-100 μm, and the lithium layer 1 has a thickness of (positive electrode surface capacity (1-coulombic efficiency) 5+ expected cycle number + (0-10)) μm, the battery has an optimal lithium dendrite resistance and capacity; when the exposed layer is not enough, the battery is easy to be short-circuited; the metal lithium layer 1 is not sufficient and the cycle number of the battery is not high.
The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.
Claims (10)
1. A composite of glass fiber and metallic lithium in a hierarchical structure, which is characterized in that: including lithium layer (1), be provided with glass fiber layer (2) in lithium layer (1), the bottom of glass fiber layer (2) is wrapped up in lithium layer (1) completely, the top exposes in the outside on lithium layer (1), the upper surface is provided with conducting layer (3), the upper end is exposed state in glass fiber layer (2), conducting layer (3) have lithium affinity and electron conductivity, the naked top of glass fiber layer (2) does not have electron or ion conductivity.
2. The compound of claim 1, wherein: the conducting layer (3) is made of one or more of lithium-philic metal materials and poly (3, 4-ethylenedioxythiophene).
3. The compound of claim 1, wherein: the glass fiber layer (2) is made of glass fiber braided fabric.
4. The compound of claim 1, wherein: the glass fiber has an electrical conductivity of less than 10-8S/cm。
5. The compound of claim 1, wherein: the exposed thickness of the upper end of the glass fiber layer (2) is 5-30 μm, and the exposed thickness is (positive electrode surface capacity 5+ (0-5)) μm.
6. The compound of claim 1, wherein: the thickness of the lithium layer (1) is 10-100 μm, and the thickness of the lithium layer (1) is (positive electrode face capacity (1-coulombic efficiency) 5+ expected cycle number + (0-10)) μm.
7. A method for preparing a complex according to any one of claims 1 to 3, characterized in that: comprises the following steps of (a) carrying out,
s1, adhering the upper surface of the glass fiber layer (2) by using an adhesive tape, adding the conductive layer (3) to the middle and lower surfaces of the glass fiber layer (2) by at least one of sputtering, spraying, liquid phase chemical deposition, vapor phase chemical deposition, chemical plating and electroplating, and tearing off the corresponding adhesive tape to obtain graded glass fibers;
s2, melting the metal lithium, inserting the graded glass fiber into the molten metal lithium, and then solidifying and forming;
s3, placing the above compound into a sealed bag and performing isostatic pressing operation to press the lithium metal into the graded glass fiber.
8. The method for preparing a composite according to claim 7, wherein: in step S1, the glass fiber layer (2) is sputtered from above using a sputtering apparatus, and the plating of the middle and lower surfaces of the glass fiber layer (2) is completed.
9. The method for preparing a composite according to claim 7, wherein: in step S1, the glass fiber layer (2) is sprayed with an aqueous solution of poly (3, 4-ethylenedioxythiophene), bonded to the unmasked surface of the glass fiber layer (2), and dried to adhere to the surface of the glass fiber layer (2) to form the conductive layer (3).
10. The method for preparing a composite according to claim 7, wherein: in step S1, the glass fiber layer (2) is treated with a solution of palladium chloride and tin dichloride to form palladium metal on the unmasked surface of the glass fiber layer (2), and then the cathode plating metal layer is connected to form the conductive layer (3).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010318876.6A CN111613773B (en) | 2020-04-21 | 2020-04-21 | Composite of glass fiber with hierarchical structure and metallic lithium and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010318876.6A CN111613773B (en) | 2020-04-21 | 2020-04-21 | Composite of glass fiber with hierarchical structure and metallic lithium and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111613773A CN111613773A (en) | 2020-09-01 |
| CN111613773B true CN111613773B (en) | 2022-06-14 |
Family
ID=72197567
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010318876.6A Active CN111613773B (en) | 2020-04-21 | 2020-04-21 | Composite of glass fiber with hierarchical structure and metallic lithium and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111613773B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114127986B (en) * | 2021-03-17 | 2022-10-11 | 宁德新能源科技有限公司 | Negative pole piece, electrochemical device and electronic device |
| CN114375511B (en) * | 2021-04-28 | 2023-12-22 | 宁德新能源科技有限公司 | Electrode sheet, electrochemical device and electronic equipment comprising same |
| WO2022226862A1 (en) * | 2021-04-29 | 2022-11-03 | The Hong Kong Polytechnic University | Current collector for battery and method for fabricating the same |
| CN115020657B (en) * | 2022-07-27 | 2024-01-30 | 西安交通大学 | Alkali metal composite negative electrode and integrated preparation method thereof |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008103258A (en) * | 2006-10-20 | 2008-05-01 | Idemitsu Kosan Co Ltd | Solid electrolyte sheet, electrode sheet, and all-solid secondary battery using it |
| CN108232117A (en) * | 2018-01-27 | 2018-06-29 | 浙江大学 | A kind of lithium metal battery negative material and its preparation method and application |
| CN108281612A (en) * | 2018-01-19 | 2018-07-13 | 浙江大学 | A kind of compound lithium an- ode |
| CN108365200A (en) * | 2018-02-11 | 2018-08-03 | 清华大学 | A kind of preparation method of compound lithium an- ode |
| CN208111570U (en) * | 2018-01-27 | 2018-11-16 | 浙江大学 | A kind of novel lithium metal battery |
| WO2019009017A1 (en) * | 2017-07-04 | 2019-01-10 | 国立研究開発法人物質・材料研究機構 | Negative electrode structure for metal batteries and metal battery using same |
| CN109686921A (en) * | 2018-11-21 | 2019-04-26 | 清华大学 | A kind of composition metal cathode of lithium and preparation method thereof with lithium carbon compound interface layer |
| CN110061191A (en) * | 2019-05-05 | 2019-07-26 | 国联汽车动力电池研究院有限责任公司 | A kind of 3-dimensional metal cathode of lithium and the preparation method and application thereof |
| CN110299512A (en) * | 2019-06-25 | 2019-10-01 | 西安交通大学 | A kind of preparation method of the lithium metal battery cathode of carbon/tin multiple base support |
| CN110350147A (en) * | 2019-06-06 | 2019-10-18 | 西安交通大学 | A kind of integrated-type tunica fibrosa battery component |
| CN110931712A (en) * | 2019-12-10 | 2020-03-27 | 清华大学 | Composite metal lithium cathode with filler and preparation method thereof |
-
2020
- 2020-04-21 CN CN202010318876.6A patent/CN111613773B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008103258A (en) * | 2006-10-20 | 2008-05-01 | Idemitsu Kosan Co Ltd | Solid electrolyte sheet, electrode sheet, and all-solid secondary battery using it |
| WO2019009017A1 (en) * | 2017-07-04 | 2019-01-10 | 国立研究開発法人物質・材料研究機構 | Negative electrode structure for metal batteries and metal battery using same |
| CN108281612A (en) * | 2018-01-19 | 2018-07-13 | 浙江大学 | A kind of compound lithium an- ode |
| CN108232117A (en) * | 2018-01-27 | 2018-06-29 | 浙江大学 | A kind of lithium metal battery negative material and its preparation method and application |
| CN208111570U (en) * | 2018-01-27 | 2018-11-16 | 浙江大学 | A kind of novel lithium metal battery |
| CN108365200A (en) * | 2018-02-11 | 2018-08-03 | 清华大学 | A kind of preparation method of compound lithium an- ode |
| CN109686921A (en) * | 2018-11-21 | 2019-04-26 | 清华大学 | A kind of composition metal cathode of lithium and preparation method thereof with lithium carbon compound interface layer |
| CN110061191A (en) * | 2019-05-05 | 2019-07-26 | 国联汽车动力电池研究院有限责任公司 | A kind of 3-dimensional metal cathode of lithium and the preparation method and application thereof |
| CN110350147A (en) * | 2019-06-06 | 2019-10-18 | 西安交通大学 | A kind of integrated-type tunica fibrosa battery component |
| CN110299512A (en) * | 2019-06-25 | 2019-10-01 | 西安交通大学 | A kind of preparation method of the lithium metal battery cathode of carbon/tin multiple base support |
| CN110931712A (en) * | 2019-12-10 | 2020-03-27 | 清华大学 | Composite metal lithium cathode with filler and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| Dendrite-Free Lithium Deposition Induced by Uniformly Distributed Lithium Ions for Effi cient Lithium Metal Batteries;Xin-Bing Cheng;《Adv. Mater》;20160222;全文 * |
| Insulative Microfiber 3D Matrix as a HostMaterial Minimizing Volume Change of the Anode of Li Metal Batteries;Shoichi Matsuda;《ACS Energy Lett》;20170330;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111613773A (en) | 2020-09-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Wang et al. | Infiltrating lithium into carbon cloth decorated with zinc oxide arrays for dendrite-free lithium metal anode | |
| CN111613773B (en) | Composite of glass fiber with hierarchical structure and metallic lithium and preparation method thereof | |
| CN108232114B (en) | Composite cathode, preparation and application thereof in preparation of lithium ion battery | |
| Zhang et al. | Coralloid carbon fiber-based composite lithium anode for robust lithium metal batteries | |
| Deng et al. | Graphene nested porous carbon current collector for lithium metal anode with ultrahigh areal capacity | |
| Xu et al. | Honeycomb-like porous 3D nickel electrodeposition for stable Li and Na metal anodes | |
| CN108550858A (en) | A kind of ormolu collector inhibiting Li dendrite | |
| CN109326792B (en) | Lithium alloy negative electrode material and preparation method thereof | |
| CN110190243A (en) | A kind of preparation and application of the lithium an- ode with composite membrane | |
| CN112151799B (en) | Three-dimensional porous interconnected framework lithium metal battery negative electrode material and preparation method thereof | |
| CN107910496A (en) | A kind of secondary cell lithium anode, preparation method and applications | |
| CN108281612A (en) | A kind of compound lithium an- ode | |
| CN113937269B (en) | Silver particle coating modified three-dimensional porous copper current collector-lithium negative electrode integrated structure and preparation method and application thereof | |
| Jin et al. | Vertical nanoarrays with lithiophilic sites suppress the growth of lithium dendrites for ultrastable lithium metal batteries | |
| Wei et al. | MOF‐derived materials enabled lithiophilic 3D hosts for lithium metal anode—A Review | |
| CN110600677A (en) | Lithium metal negative electrode, preparation method thereof and lithium metal, lithium sulfur and lithium air battery | |
| CN114883560B (en) | Three-dimensional current collector/Zn/Zn-E composite negative electrode, preparation thereof and application thereof in water-based zinc ion battery | |
| CN112768697A (en) | Composite lithium metal negative current collector and preparation method and application thereof | |
| CN111403678B (en) | Three-dimensional flexible metal cathode and preparation method thereof | |
| Tian et al. | Electrodeposition behavior of lithium metal on carbon substrates with surface silvering | |
| Park et al. | Fabrication and characterization of Li-coated nickel mesh for anode of lithium-metal batteries | |
| Hu et al. | CuO nanofilm-covered Cu microcone coating for a long cycle Li metal anode by in situ formed Li2O | |
| Cheng et al. | Rooting Zn into metallic Na bulk for energetic metal anode | |
| CN112968174B (en) | Lithium-philic alloy modification layer, composite lithium negative electrode material, and preparation methods and applications of lithium-philic alloy modification layer and composite lithium negative electrode material | |
| CN114284475A (en) | Preparation method of composite lithium metal cathode with three-dimensional structure and product thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |