CN115036555A - Secondary battery and electric equipment - Google Patents
Secondary battery and electric equipment Download PDFInfo
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- CN115036555A CN115036555A CN202210814204.3A CN202210814204A CN115036555A CN 115036555 A CN115036555 A CN 115036555A CN 202210814204 A CN202210814204 A CN 202210814204A CN 115036555 A CN115036555 A CN 115036555A
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- 229910052718 tin Inorganic materials 0.000 claims description 4
- 229910052719 titanium Inorganic materials 0.000 claims description 4
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Classifications
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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
-
- 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
-
- 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
- H01M4/625—Carbon or graphite
-
- 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
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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
- H01M2300/00—Electrolytes
- H01M2300/0085—Immobilising or gelification of electrolyte
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
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- Engineering & Computer Science (AREA)
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- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Battery Electrode And Active Subsutance (AREA)
- Secondary Cells (AREA)
Abstract
The invention discloses a secondary battery and an electric device. The secondary battery comprises a lithium metal layer, a solid electrolyte layer and a negative electrode interface modification layer arranged between the lithium metal layer and the solid electrolyte layer, wherein the negative electrode interface modification layer comprises a metal micron line and a carbon material, and the length of the metal micron line is 0.5-100 microns. The secondary battery comprises the cathode interface modification layer arranged between the metal lithium cathode and the solid electrolyte, so that the direct contact between the solid electrolyte and the metal lithium can be reduced, the interface stability of the metal cathode side of the solid battery lithium is obviously improved, the uniform deposition of lithium ions is facilitated, the growth of lithium dendrites is inhibited, the utilization rate of the battery is increased, and the cycle life of the battery is prolonged.
Description
Technical Field
The invention relates to the field of secondary batteries, in particular to a secondary battery and electric equipment.
Background
The lithium metal cathode has low chemical potential (-3.04V vs. SHE) and high theoretical capacity (3860mAh g -1 ) And the like, and is always considered as the most ideal negative electrode material of the lithium battery. However, the high activity of metallic lithium and the formation of lithium dendrites during battery cycling severely hamper the commercialization of metallic lithium negative electrodes.
Solid-state batteries, which employ a high mechanical strength solid electrolyte to inhibit penetration of lithium dendrites, are considered to be the most effective method of overcoming lithium dendrites. However, most solid electrolytes are unstable to metallic lithium, form interfacial layers during standing and cycling, consume the metallic lithium, and have high interfacial layer resistance, degrade the performance of the battery, and cause failure of the battery.
Chinese patent CN202110914122.1 discloses a solid-state lithium metal battery with a negative electrode interface modification layer, wherein the negative electrode interface modification layer is located between the negative electrode of lithium metal and the solid-state electrolyte, and the negative electrode interface modification layer is an aluminum nitride coating prepared on the solid-state electrolyte by magnetron sputtering.
Disclosure of Invention
The primary objective of the present invention is to overcome the problems of poor chemical stability of the interface between the solid electrolyte and the lithium metal negative electrode, easy growth of lithium dendrite, and large interface impedance, and to provide a secondary battery comprising a lithium metal layer, a solid electrolyte layer, and a negative electrode interface modification layer disposed between the lithium metal layer and the solid electrolyte layer. The cathode interface modification layer can reduce the direct contact between the solid electrolyte and the metal lithium, remarkably improve the interface stability of the metal cathode side of the solid battery lithium, facilitate the uniform deposition of lithium ions, and inhibit the growth of lithium dendrites, thereby improving the utilization rate and the cycle life of the battery.
The invention also aims to provide a preparation method of the negative electrode interface modification layer.
It is still another object of the present invention to provide an electric device including the secondary battery.
In order to achieve the purpose, the invention adopts the technical scheme that:
in one aspect, the present invention provides a secondary battery, including a lithium metal layer, a solid electrolyte layer, and a negative electrode interface modification layer disposed between the lithium metal layer and the solid electrolyte layer, wherein the negative electrode interface modification layer includes a metal microwire and a carbon material, and the length of the metal microwire is 0.5 μm to 100 μm.
In some embodiments of the present invention, the length of the metal microwire is 1 μm to 10 μm.
In some embodiments of the present invention, the aspect ratio of the metal microwires is (10-1000): 1.
in some embodiments of the present invention, the aspect ratio of the metal microwire is (50-200): 1. when the length-diameter ratio of the metal micron line is (50-200): 1, the conductivity of the cathode interface modification layer can be further improved, so that the interface impedance of the solid electrolyte and the lithium metal cathode is reduced, and the chemical stability of the interface is improved.
In some embodiments of the present invention, the metal of the metal microwire has a purity of 80% or more.
The metal impurities are less, the conductivity and the ion conductivity are better, and the chemical stability and the interface impedance of the solid electrolyte and the lithium metal negative electrode can be further improved.
In some embodiments of the present invention, the metal of the metal microwire has a purity of 95% or more.
In some embodiments of the present invention, the metal of the metal microwire comprises a metal capable of forming an alloy with metallic lithium.
In some embodiments of the invention, the metal comprises one or more of Ag, Zn, Zr, Sn and Ti. Ag. After Zn, Zr, Sn and Ti are alloyed with the metallic lithium, the affinity energy of the metallic lithium can be reduced, the conduction of lithium ions is facilitated, and the deposition of the lithium ions is regulated.
In some embodiments of the present invention, the metal microwire is contained in an amount of 20 wt% or more based on the total weight of the anode interface modification layer.
The content of the metal microwire is high, the conductivity of the cathode interface modification layer is better, the interface impedance is low, and the chemical stability is good, but when the content of the metal microwire is too high, the ion conductivity is poor, and the interface impedance is high.
In some embodiments of the present invention, the metal microwire is included in an amount of 30 wt% to 40 wt% based on the total weight of the negative electrode interface modification layer.
In some embodiments of the present invention, the carbon material is present in an amount of 75 wt% or less based on the total weight of the anode interface modification layer.
The carbon material is less, the better the conductivity of the negative electrode interface modification layer, the lower the interface resistance, and the better the chemical stability, but when the carbon material is too small, the ion conductivity is deteriorated, and the interface resistance becomes high.
In some embodiments of the present invention, the carbon material is present in an amount of 55 wt% to 65 wt%, based on the total weight of the negative electrode interface modification layer.
In some embodiments of the invention, the carbon material comprises one or more of conductive carbon black, graphene, vapor grown carbon fiber.
In some embodiments of the invention, the negative electrode interface modifying layer further comprises an aqueous binder.
In some embodiments of the invention, the aqueous binder comprises one or more of CMC (sodium carboxymethylcellulose), PAA (polyacrylic acid), and PVA (polyvinyl alcohol). CMC, PVA and PAA as aqueous binders are more stable to metallic lithium negative electrodes and have better compatibility than PVDF.
In some embodiments of the present invention, the thickness of the negative electrode interface modification layer may be 0.5 to 30 μm.
The negative electrode interface modification layer has lithium ion conductivity, however, the lithium ion conductivity of the negative electrode interface modification layer may be lower than that of the electrolyte layer. Therefore, the cathode interface modification layer is too thick, which can hinder the conduction of lithium ions and increase the interface impedance. And if the cathode interface modification layer is too thin, the chemical stability of the interface is reduced.
In some embodiments of the invention, the thickness of the negative electrode interface modification layer is 8-15 μm.
In some embodiments of the invention, the porosity of the negative electrode interface modification layer is less than or equal to 5%.
The carbon in the cathode interface modification layer is used as a skeleton structure, so that lithium ions and electrons can be conducted, and the metal micrometer wire can perform reversible alloying/dealloying reaction with the lithium ions and is used as a transmission channel of the lithium ions in the buffer layer. In addition, the metal micron line can improve the electron conductivity of the buffer layer and has the effect of framework support.
In another aspect, the invention provides a method for preparing the cathode interface modification layer.
The preparation method of the cathode interface modification layer provided by the invention comprises the following steps:
(1) mixing the metal micron wires, the carbon material, the binder and water according to a ratio, and stirring and dispersing to obtain buffer layer slurry;
(2) coating the obtained buffer layer slurry on a sacrificial substrate through a coating process, drying, and forming a composite buffer layer on the sacrificial substrate to obtain a pole piece loaded with the composite buffer layer;
(3) covering solid electrolyte powder or a solid electrolyte membrane above the composite buffer layer of the pole piece, and pressing and jointing the pole piece and the solid electrolyte through a cold pressing or hot pressing process;
(4) and mechanically stripping the sacrificial substrate and the solid electrolyte layer, so that the composite buffer layer is applied to the solid electrolyte side, and the cathode interface modification layer is obtained.
In some embodiments of the present invention, in the step (1), the mixing is performed by ball milling, the rotation speed may be 1500-2500 rpm, and the time may be 1-3 h.
In some embodiments of the invention, in the above step (1), the binder comprises one or more of CMC, PAA and PVA. The water-based binders CMC, PAA and PVA are used, no organic solvent is involved in the preparation process, and the process is more environment-friendly.
Preferably, the binder comprises CMC. The pole piece prepared by using CMC as a binder has weaker bonding force, can be better pressed and transferred, and meanwhile, sodium ions and anions can be decomposed from the CMC in an aqueous solution.
In some embodiments of the present invention, in the step (2), the sacrificial substrate used comprises Cu, Al or Fe, and has a thickness of 5 to 15 μm, and the coating manner comprises at least one of blade coating, coating roller, spin coating, spray coating, coating brush, and the like.
In some embodiments of the invention, in step (3), the electrolyte comprises at least one of LGPS, LPSCl, LATP, LLZO, and the like.
In some embodiments of the present invention, the solid electrolyte layer includes solid electrolyte particles having a particle size of 0.1 to 100 μm.
In some embodiments of the present invention, the solid electrolyte layer includes solid electrolyte particles having a particle size of 0.2 to 1 μm. The particle size of the solid electrolyte particles is within the range, and the battery has better comprehensive performance.
In some embodiments of the present invention, the porosity of the solid electrolyte layer is 0.1 to 20%.
In some embodiments of the invention, the porosity of the solid electrolyte layer is between 5% and 15%.
In some embodiments of the invention, the thickness of the anode interface modification layer is H1 μm, the thickness of the solid electrolyte layer is H2 μm, and the requirement that the thickness is 0.0005. ltoreq.H 1/H2. ltoreq.0.2 is satisfied, wherein the thickness is 50. ltoreq.H 2. ltoreq.5000.
In another aspect, the invention also provides an electric device.
The electric equipment provided by the invention comprises the secondary battery.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a negative electrode interface modification layer which comprises a metal micrometer wire and a carbon material, wherein the metal micrometer wire and the carbon material have specific lengths and can form an alloy with metal lithium, and the negative electrode interface modification layer is arranged between a metal lithium negative electrode and a solid electrolyte, so that the polarization voltage (less than or equal to 0.05V) can be reduced, the lithium stability cycle time (more than or equal to 800h) can be prolonged, the interface chemical stability between the solid electrolyte and the metal lithium negative electrode can be improved, lithium dendrite can be reduced, and the interface impedance can be reduced.
Drawings
Fig. 1 is a schematic view of an interface modification layer according to the present invention.
Fig. 2 is a graph showing the effect of the interface modification layer (example 1) and the interface modification layer (comparative example 1) on the lithium stability cycle test in the present invention.
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. The examples provided below serve as a guide for further modifications by a person skilled in the art and do not constitute a limitation of the invention in any way.
The experimental procedures in the following examples, unless otherwise indicated, are conventional and are carried out according to the techniques or conditions described in the literature in the field or according to the instructions of the products. Materials, reagents and the like used in the following examples are commercially available unless otherwise specified.
The invention provides a secondary battery, which comprises a lithium metal layer, a solid electrolyte layer and a negative electrode interface modification layer arranged between the lithium metal layer and the solid electrolyte layer, wherein the negative electrode interface modification layer is arranged between a lithium metal negative electrode and the solid electrolyte of the secondary battery and is applied to the solid electrolyte;
the negative electrode interface modification layer comprises a metal micron line and a carbon material, wherein the length of the metal micron line is 0.5-100 microns, preferably 1-10 microns.
The length-diameter ratio of the metal micron line is (10-1000): 1, preferably (50-200): 1.
the purity of the metal micron line is more than 80%.
The purity of the metal micron line is more than 95%.
The purity of the metal micron line is 95-99%.
The metal of the metal microwire comprises a metal capable of forming an alloy with metallic lithium.
The metal comprises one or more of Ag, Zn, Zr, Sn and Ti.
The content of the metal microwire is more than 20 wt% based on the total weight of the negative electrode interface modification layer.
Based on the total weight of the cathode interface modification layer, the content of the metal microwire is 30-40 wt%. The content of the carbon material is 75 wt% or less, preferably 55 wt% to 65 wt%.
The carbon material comprises one or more of conductive carbon black, graphene and vapor grown carbon fiber.
The negative electrode interface modification layer also comprises a water-based binder, and the water-based binder contains one or more of CMC, PVA and PAA.
The thickness of the negative electrode interface modification layer is 0.5-30 mu m, and preferably 8-15 mu m.
The porosity of the negative electrode interface modification layer is less than or equal to 5%.
The invention also provides a secondary battery, which comprises a lithium metal layer, a solid electrolyte layer and the negative electrode interface modification layer arranged between the lithium metal layer and the solid electrolyte layer.
The thickness of the cathode interface modification layer is H1 mu m, the thickness of the solid electrolyte layer is H2 mu m, the requirement that H1/H2 is more than or equal to 0.0005 is less than or equal to 0.2, and H2 is more than or equal to 50 and less than or equal to 5000.
The invention also provides an electric device comprising the secondary battery.
According to the invention, the direct contact between the solid electrolyte and the metal lithium is reduced by using the cathode interface modification layer of the micron metal wire and carbon, the interface stability of the solid battery lithium metal cathode side is obviously improved, the deposition of lithium ions is facilitated, the growth of lithium dendrites is inhibited, and the utilization rate and the cycle life of the battery are improved.
The Ag microwires in the examples below are the product of alatin;
CMC and SP are products of Ningbo lithium New energy science and technology Limited.
Example 1
The embodiment provides a preparation method of a negative electrode interface modification layer, which comprises the following steps:
(1) mixing Ag micron wires (length 3 mu m, length-diameter ratio 100:1, purity 99%), a carbon material (SP), a binder (CMC) and water in proportion, and stirring and dispersing to obtain buffer layer slurry (solid content is 40%); wherein, Ag micron line accounts for 40 wt%, carbon material accounts for 55 wt%, binder accounts for 5 wt%,
(2) coating the buffer layer slurry on a sacrificial substrate Cu (with the thickness of 8 microns) by a blade coating process, wherein the thickness of the sacrificial substrate Cu is 60 microns, and drying to obtain a pole piece loaded with a composite buffer layer;
(3) pressing 100mg of LGPS powder (with a particle size of 0.2 μm) under 360MPa for 1min to obtain an electrolyte sheet, wherein the porosity of the electrolyte layer is 5% and the layer thickness is 1000 μm; cutting the pole piece into a proper size, covering a solid electrolyte sheet on the pole piece, and cold-pressing for 1min under the pressure of 200MPa to press the pole piece on the electrolyte sheet;
(4) and mechanically stripping the sacrificial substrate and the solid electrolyte layer to apply the composite buffer layer to the solid electrolyte side, thereby obtaining the negative electrode interface modification layer with the porosity of 1% and the thickness of 10 micrometers.
Example 2
This example is different from example 1 in that Sn micron line is used instead of Ag micron line.
Example 3
This example is different from example 1 in that Zn microwire is used instead of Ag microwire.
Example 4
This example is different from example 1 in that Zr microwires are used instead of Ag microwires.
Example 5
This example is different from example 1 in that the purity of the Ag micron line was 95%.
Example 6
This example is different from example 1 in that the purity of the Ag micron line was 80%.
Example 7
This example differs from example 1 in that the aspect ratio of the Ag micron line is 50: 1.
Example 8
This example differs from example 1 in that the aspect ratio of the Ag micron line is 200: 1.
Example 9
This example differs from example 1 in that the aspect ratio of the Ag micron line is 10: 1.
Example 10
This example differs from example 1 in that the aspect ratio of the Ag micron line is 1000: 1.
Example 11
The difference between the embodiment and the embodiment 1 is that the cold pressing pressure is changed to 150Mpa, so that the porosity of the cathode interface modification layer is 2%.
Example 12
The difference between the embodiment and embodiment 1 is that the cold pressing pressure is changed to 100Mpa, so that the porosity of the cathode interface modification layer is 5%.
Example 13 example 16
The difference from example 1 was that the ratio of the Ag microwire to the carbon material was adjusted to the value shown in table 1.
Example 17
This example differs from example 1 in that PVDF is used as the binder.
Examples 18 to 23
The difference from example 1 is that the thickness of the electrolyte layer was adjusted to the value shown in table 1 by adjusting the amount of the electrolyte powder.
Example 24 example 29
The difference from example 1 is that in step (2), the coating thickness was adjusted to give the thickness of the modified layer described in Table 1.
Example 30 example 36
The difference from example 1 is that the length of the Ag micrometer line was adjusted to the value shown in table 1.
Comparative example 1
This comparative example does not contain an interface modifier, and is otherwise the same as example 1.
Comparative example 2
This comparative example does not contain a carbon material, and is otherwise the same as example 1.
Comparative example 3
This comparative example does not contain metal microwires, and is otherwise the same as example 1.
Performance testing
In examples 1 to 36 and comparative examples 1 to 3, after the electrolyte layer with the modification layer was pressed, the sacrificial substrate was removed, and metal lithium was added to both sides to assemble a symmetrical battery, followed by performance testing.
The symmetrical battery performance test method comprises the following steps: at room temperature, a 10mA blue charging and discharging test device is adopted to carry out the performance test of the symmetrical battery, and the charging and discharging current density is 0.1mA/cm 2 The charge and discharge capacity is 0.1mAh/cm 2 . Table 1 lists specific parameters of examples 1-36 and comparative examples 1-3.
TABLE 1
As can be seen from the examples and comparative examples in Table 1, the negative electrode interface modification layer provided by the invention is arranged between the lithium metal negative electrode and the solid electrolyte, and can reduce the polarization voltage (less than or equal to 0.05V) and prolong the lithium stability cycle time (more than or equal to 800h), thereby improving the chemical stability of the interface between the solid electrolyte and the lithium metal negative electrode, reducing lithium dendrites and reducing the interface impedance.
As can be seen from comparative examples 1 to 4, the present invention has no special requirements for the type of the metal microwire, and the conventional metal microwire in the art can be used in the present invention.
It is understood from the comparison of examples 1 and 5 to 6 that the purity of the metal microwire affects the polarization voltage and the stability against lithium cycle time, and the higher the purity of the metal microwire, the smaller the polarization voltage and the longer the stability against lithium cycle time, because the impurity conductivity and the ionic conductivity in the metal wire are poor.
Comparing the embodiment 1 with the embodiment 7-10, it is known that the length-diameter ratio of the metal micron line also affects the polarization voltage and the stable cycle time of lithium, and too small length-diameter ratio of the metal line causes poor conductivity of an interface layer, which causes the polarization voltage to be increased and the cycle life of the symmetrical battery to be reduced; too large length-diameter ratio of the metal wire can lead to transition concentration and ineffective dispersion of the metal wire, and also lead to poor conductivity of an interface layer, thus causing increase of polarization voltage and reduction of cycle life of the symmetrical battery.
It is understood from comparison between example 1 and examples 11 to 12 that the smaller the porosity of the modification layer, the smaller the polarization voltage and the longer the cycle time for lithium stability, because the smaller the porosity, the fewer the interface layer defects and the better the conductivity and ion conductivity, the smaller the polarization voltage and the longer the cycle time for lithium stability.
It is understood from the comparison of examples 1 and 13 to 16 that the microwire content is high, the carbon material content is small, the poling voltage is small, and the cycle time for lithium stability is longer because the carbon material is small and the conductivity of the interface layer is better, so that the poling voltage is small and the cycle time for lithium stability is long, but when the carbon material is too small, the ion conductivity is deteriorated and the poling voltage is increased.
It is understood from comparison of example 1 and example 17 that the kind of binder also affects the polarization voltage and the cycle time for lithium stability, and when CMC is used as the binder, the polarization voltage is smaller and the cycle time for lithium stability is longer due to the better stability of the aqueous binder to the metallic lithium negative electrode and compatibility with the metallic lithium.
It is understood from the comparison between example 1 and examples 18 to 23 that when the electrolyte layer is too thin, the polarization voltage is small, but the cycle time for lithium stability is short; when the electrolyte layer is too thick, the lithium stability cycle time is longer, but the polarization voltage is larger, and the performance is more balanced when the electrolyte layer is 1000-3000 μm thick.
It can be seen from the comparison between example 1 and examples 24-29 that the thickness of the modified layer also affects the polarization voltage and the stability cycle time for lithium, and the properties are more balanced when the thickness of the modified layer is 8-15 μm.
Comparing example 1 with examples 30-36, it can be seen that the length of the metal microwire affects the polarization voltage and the lithium stability cycle time, because too short a metal microwire results in poor conductivity of the interface layer, resulting in an increase in polarization voltage and a decrease in cycle life of the symmetric battery; too long metal wires lead to transition concentration and ineffective dispersion of the metal wires, poor conductivity of an interface layer, increased polarization voltage and reduced cycle life of the symmetrical battery, and the performance is better when the length of the metal micron wires is 1-10 mu m.
The present invention has been described in detail above. It will be apparent to those skilled in the art that the invention can be practiced in a wide range of equivalent parameters, concentrations, and conditions without departing from the spirit and scope of the invention and without undue experimentation. While the invention has been described with reference to specific embodiments, it will be appreciated that the invention can be further modified. In general, this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains.
Claims (10)
1. A secondary battery is characterized by comprising a lithium metal layer, a solid electrolyte layer and a negative electrode interface modification layer arranged between the lithium metal layer and the solid electrolyte layer, wherein the negative electrode interface modification layer comprises metal microwires and a carbon material, and the length of each metal microwire is 0.5-100 micrometers.
2. The secondary battery according to claim 1, wherein the aspect ratio of the metal microwire is (50-200): 1.
3. the secondary battery according to claim 1, wherein the metal in the metal microwire comprises one or more of Ag, Zn, Zr, Sn and Ti.
4. The secondary battery according to claim 3, wherein the metal of the metal microwire has a purity of 80% or more, preferably 95% or more.
5. The secondary battery according to claim 1, wherein the content of the metal microwire is 20 wt% or more, preferably 30 wt% to 40 wt%, based on the total weight of the negative electrode interface modification layer.
6. The secondary battery according to claim 1, wherein the carbon material is contained in an amount of 75 wt% or less, preferably 55 wt% to 65 wt%, based on the total weight of the negative electrode interface modification layer;
the carbon material comprises one or more of conductive carbon black, graphene and vapor grown carbon fiber.
7. The secondary battery of claim 1, wherein the negative electrode interface modification layer further comprises an aqueous binder comprising one or more of CMC, PVA, and PAA.
8. The secondary battery according to claim 1, wherein the thickness of the negative electrode interface modification layer is 0.5 to 30 μm, preferably 8 to 15 μm;
the porosity of the negative electrode interface modification layer is less than or equal to 5%.
9. The secondary battery according to claim 1, characterized in that: the thickness of the cathode interface modification layer is H1 mu m, the thickness of the solid electrolyte layer is H2 mu m, H1/H2 is more than or equal to 0.0005 and less than or equal to 0.2, and H2 is more than or equal to 50 and less than or equal to 5000.
10. An electric device comprising the secondary battery according to any one of claims 1 to 9.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115763706A (en) * | 2022-11-21 | 2023-03-07 | 上海屹锂新能源科技有限公司 | Alloy/carbon composite film for all-solid-state battery and preparation method thereof |
| WO2024011871A1 (en) * | 2022-07-12 | 2024-01-18 | 欣旺达电子股份有限公司 | Secondary battery and electrical device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108923022A (en) * | 2018-05-23 | 2018-11-30 | 中国科学院青岛生物能源与过程研究所 | A kind of method of modifying improving all-solid-state battery cathode of lithium stability |
| CN109103492A (en) * | 2018-09-03 | 2018-12-28 | 江西克莱威纳米碳材料有限公司 | Hydroxyapatite nanowire-carbon nanotube film, preparation method thereof and lithium-sulfur battery |
| CN111435756A (en) * | 2019-12-27 | 2020-07-21 | 蜂巢能源科技有限公司 | Lithium battery and preparation method and application thereof |
| US20210265618A1 (en) * | 2020-02-24 | 2021-08-26 | Nissan North America, Inc. | Modified Electrolyte-Anode Interface for Solid-State Lithium Batteries |
| KR20210136832A (en) * | 2020-05-08 | 2021-11-17 | 주식회사 엘지에너지솔루션 | Negative electrode current collector for lithium free battery, electrode assembly including the same, lithium free battery |
| CN114242942A (en) * | 2021-11-30 | 2022-03-25 | 厦门大学 | Composite buffer layer with stable negative electrode interface and solid-state lithium metal battery thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113809386B (en) * | 2021-08-10 | 2022-11-18 | 武汉理工大学 | Solid-state metal lithium battery with negative electrode interface modification layer |
| CN115036555A (en) * | 2022-07-12 | 2022-09-09 | 欣旺达电子股份有限公司 | Secondary battery and electric equipment |
-
2022
- 2022-07-12 CN CN202210814204.3A patent/CN115036555A/en active Pending
- 2022-12-29 WO PCT/CN2022/143091 patent/WO2024011871A1/en unknown
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108923022A (en) * | 2018-05-23 | 2018-11-30 | 中国科学院青岛生物能源与过程研究所 | A kind of method of modifying improving all-solid-state battery cathode of lithium stability |
| CN109103492A (en) * | 2018-09-03 | 2018-12-28 | 江西克莱威纳米碳材料有限公司 | Hydroxyapatite nanowire-carbon nanotube film, preparation method thereof and lithium-sulfur battery |
| CN111435756A (en) * | 2019-12-27 | 2020-07-21 | 蜂巢能源科技有限公司 | Lithium battery and preparation method and application thereof |
| US20210265618A1 (en) * | 2020-02-24 | 2021-08-26 | Nissan North America, Inc. | Modified Electrolyte-Anode Interface for Solid-State Lithium Batteries |
| KR20210136832A (en) * | 2020-05-08 | 2021-11-17 | 주식회사 엘지에너지솔루션 | Negative electrode current collector for lithium free battery, electrode assembly including the same, lithium free battery |
| CN114242942A (en) * | 2021-11-30 | 2022-03-25 | 厦门大学 | Composite buffer layer with stable negative electrode interface and solid-state lithium metal battery thereof |
Non-Patent Citations (2)
| Title |
|---|
| 张强;姚霞银;张洪周;张联齐;许晓雄;: "全固态锂电池界面的研究进展", 储能科学与技术, vol. 5, no. 5, 1 September 2016 (2016-09-01), pages 659 - 667 * |
| 温兆银;靳俊;谷穗;马国强;: "锂硫电池中的表面修饰", 硅酸盐学报, vol. 45, no. 10, 14 July 2017 (2017-07-14), pages 1367 - 1381 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024011871A1 (en) * | 2022-07-12 | 2024-01-18 | 欣旺达电子股份有限公司 | Secondary battery and electrical device |
| CN115763706A (en) * | 2022-11-21 | 2023-03-07 | 上海屹锂新能源科技有限公司 | Alloy/carbon composite film for all-solid-state battery and preparation method thereof |
| CN115763706B (en) * | 2022-11-21 | 2024-03-12 | 上海屹锂新能源科技有限公司 | Alloy/carbon composite film for all-solid-state battery and preparation method thereof |
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