A lithium metal anode with an interfacial modification layer and a preparation method thereof

Abstract

The present invention discloses a lithium metal anode with an interfacial modification layer and a preparation method thereof. The surface of the lithium metal anode has an interfacial modification layer, and the interfacial modification layer includes at least one lithiumophilic layer and at least one lithium-phobic layer; the lithiumophilic layer is an electronic conductor, and the lithium-phobic layer is an ion conductor and an electronic insulator. The lithiumophilic layer can guide the uniform and dense deposition of lithium metal, and the lithium-phobic layer has a high interfacial energy and is relatively stable to lithium metal; in addition, due to the difference in lithium metal affinity between the lithiumophilic layer and the lithium-phobic layer, there is a space charge layer at the interface between the two, and a lithiumophilic layer / lithium-phobic layer solid electrolyte interface is spontaneously formed during the charge and discharge process, which has the function of protecting lithium metal and inhibiting lithium dendrites. During the charge and discharge process of the lithium metal battery, this interfacial modification layer can inhibit the formation of lithium dendrites, reduce side reactions, improve the Coulomb efficiency, and obtain uniform and dense deposition.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and particularly relates to a lithium metal negative electrode with an interfacial modification layer and a preparation method thereof. Background Art

[0002] Lithium-ion batteries have been widely used in the fields of automobiles, electronic products, energy storage, etc. due to their high energy density and good cycle performance, and further high requirements are put forward for their performance. However, the negative electrodes of existing lithium-ion battery systems are mainly graphite, and its theoretical capacity is only ~370 mAh / g. The performance exploration has basically approached its theoretical value, and it is difficult to further improve it essentially. Lithium metal has a high theoretical capacity of 3860 mAh / g and the lowest reduction potential. As a new battery negative electrode, lithium metal is considered to be the most promising next-generation technology.

[0003] However, there are mainly three problems with lithium metal negative electrodes during charge and discharge: (1) lithium dendrites are formed, which are prone to causing safety hazards; (2) due to the lowest reduction potential, lithium metal continuously undergoes side reactions with the electrolyte / electrolyte solution, consuming the electrolyte / electrolyte solution and lithium metal, forming a relatively thick solid electrolyte interface (SEI), increasing the battery impedance; (3) the volume and morphology change significantly, causing the rupture of the solid electrolyte interface, further exacerbating the side reaction between lithium metal and the electrolyte / electrolyte solution. In order to address the problems existing in lithium metal negative electrodes, on the one hand, it is necessary to prevent the direct contact between the lithium metal negative electrode and the electrolyte / electrolyte solution to reduce side reactions, and on the other hand, it is necessary to guide the uniform deposition of lithium metal and inhibit lithium dendrites. The main technical solutions include: adjusting the components of the electrolyte, solid electrolytes, lithium metal alloying, artificial solid electrolyte interfaces, three-dimensional skeletons, etc. These technical solutions can improve some problems to a certain extent, but it is difficult to show obvious effects under the conditions of high current density and high capacity. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a lithium metal negative electrode with an interfacial modification layer and a preparation method thereof. The interfacial modification layer is composed of a lithiumophilic layer and a lithiumophobic layer, which can inhibit the formation of lithium dendrites, reduce side reactions, improve the Coulomb efficiency, and obtain uniform and dense deposition under the conditions of high current density and high capacity.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The first object of the present invention is a lithium metal negative electrode with an interface modification layer. The surface of the lithium metal negative electrode has an interface modification layer, and the interface modification layer includes at least one lithiumophilic layer and at least one lithium-phobic layer; the lithiumophilic layer is an electron conductor, and the lithium-phobic layer is an ion conductor and an electron insulator. Preferably, the thickness of the lithiumophilic layer is 0.01 to 100 μm, and the thickness of the lithium-phobic layer is 0.01 to 100 μm. The lithium metal negative electrode is pure lithium metal, a lithium metal alloy or a lithium metal host.

[0007] When the number of lithiumophilic layers is 1 layer, preferably, the lithium-phobic layer can be between the lithiumophilic layer and the lithium metal negative electrode, and / or on the outermost side.

[0008] When the number of lithiumophilic layers is greater than 1 layer and the lithiumophilicity is different, preferably, the lithiumophilic layers are arranged in a gradient order from high to low in terms of lithiumophilicity, and the lithiumophilic layer with high lithiumophilicity is close to the lithium metal negative electrode side.

[0009] Preferably, the lithium-phobic layer can be present between the lithiumophilic layer and the lithium metal negative electrode, and / or between the lithiumophilic layers, and / or on the outermost side.

[0010] When the number of lithiumophilic layers is greater than 1 layer and the lithiumophilicity is the same, preferably, the lithium-phobic layer can be present between the lithiumophilic layer and the lithium metal negative electrode, and / or between the lithiumophilic layers, and / or on the outermost side.

[0011] Preferably, the lithiumophilic layer is selected from one or more of Al, Zn, Mg, As, Au, Ag, Ga, Pb, Cd, Bi, In, Ge, Sn, B, Si, P, Ti, V, Cr, Mn, Co, Ni, Cu, Nb, Mo, Ru, oxides, nitrides, sulfides, phosphides, halides, carbon materials; in order to increase the electronic conductivity of the lithiumophilic layer, a conductive agent can be added to the lithiumophilic layer. Further preferably, the conductive agent is selected from one or more of carbon nanotubes, graphene, graphite, carbon fiber, activated carbon, Super-P (conductive carbon black), carbon black.

[0012] Preferably, the lithium-phobic layer is selected from one or more of LiF, Li3N, Li2S, Li2O, LiCl, LiBr, LiI, Li2CO3, Li2SO4, LiNO3, Li2PO3, LiClO4, LiN(CF3SO2)2, LiN(FSO2)2, LiClO4, LiCF3SO3, LiBF4, LiPF4, LiAsF6, LiB(C2O4)2, lithium carboxylate, ceramic-type solid electrolyte, polymer electrolyte, ceramic / polymer composite electrolyte.

[0013] Another object of the present invention is to provide a method for preparing the above-mentioned lithium metal negative electrode with an interface modification layer, and the steps are as follows: preparing an interface modification layer on the surface of the lithium metal negative electrode. The preparation methods of the lithiumophilic layer and the lithium-phobic layer in the interface modification layer include one or more of wet coating, screen printing, electrostatic powder planting, spraying, inkjet printing, scraping, casting, spin coating, dipping, dropping, electroplating, physical deposition, chemical deposition, and chemical reaction.

[0014] Preferably, according to the requirements of the preparation method, the materials for preparing the lithiumophilic layer and the materials for preparing the lithium-phobic layer are respectively dispersed in one or more of a solvent, a polymer binder, and a polymer monomer in the form of powder to form a slurry, and then the slurry is successively loaded on the surface of the lithium metal negative electrode; wherein, the polymer monomer can be cured into a polymer; or the powder is directly prepared without dispersion; or it is prepared in a bulk form.

[0015] Preferably, the lithiumophilic layer and the lithium-phobic layer can be directly prepared on the lithium metal, and / or pre-prepared into thin sheets and then bonded to the lithium metal negative electrode as the interface modification layer. Further, the interface modification layer of the lithium metal negative electrode can be densified by a pressing method; the pressing methods include one or more of flat static pressure, isostatic pressure, roll pressing, and stamping.

[0016] The beneficial effects of the present invention are as follows:

[0017] The interface modification layer formed on the surface of the lithium metal negative electrode of the present invention includes at least one lithiumophilic layer and at least one lithium-phobic layer; wherein, the lithiumophilic layer is an electron conductor, and the lithium-phobic layer is an ion conductor and an electron insulator. The electron-conducting lithiumophilic layer can reduce the deposition overpotential of lithium metal and guide the uniform and dense deposition of lithium metal; in addition, lithium metal can also be deposited inside the lithiumophilic layer in a chemically bonded or physically bonded manner, providing space for volume expansion. The lithium-phobic layer has a high interfacial energy, which is not conducive to the formation of lithium dendrites, and it is difficult for lithium dendrites to penetrate. Due to the difference in lithium metal affinity between the lithiumophilic layer and the lithium-phobic layer, a space charge layer is generated at the interface between the two, and a lithiumophilic layer / lithium-phobic layer solid electrolyte interface is spontaneously formed during the charge and discharge process, and lithium ions have a lower lateral conduction barrier therein; when lithium dendrites grow to the lithiumophilic layer / lithium-phobic layer solid electrolyte interface, lithium metal will deposit along the direction perpendicular to the lithium dendrites and towards the lithiumophilic layer side, thereby inhibiting lithium dendrites. In addition, the lithiumophilic layer / lithium-phobic layer solid electrolyte interface can also effectively slow down the side reactions between the electrolyte / electrolyte and lithium metal. Considering the above comprehensively, the interface modification layer can inhibit the formation of lithium dendrites, reduce side reactions, improve the Coulomb efficiency, and obtain uniform and dense deposition. Detailed implementation mode

[0018] The following further illustrates the present invention in conjunction with embodiments, so that those skilled in the art can better understand the present invention and be able to implement it, but the embodiments cited do not limit the present invention.

[0019] Example 1

[0020] In this embodiment, the lithium metal negative electrode with an interfacial modification layer includes a lithium metal negative electrode. The surface of the lithium metal negative electrode has an interfacial modification layer, and the interfacial modification layer sequentially includes a lithiumophilic layer and a lithiumophobic layer from the inside out. The structure of this lithium metal negative electrode is denoted as: lithium metal + lithiumophilic layer + lithiumophobic layer.

[0021] According to the materials corresponding to the lithiumophilic layer and the lithiumophobic layer in Table 1, a metal or non-metal element with lithiumophilicity is sputtered onto the lithium metal in a bulk form by magnetron sputtering to prepare a 100-nm-thick lithiumophilic layer; a powder of a lithiumophobic substance (LiF, Li3N, Li2S, Li2O, LiCl, LiBr, LiI, Li2CO3, or lithium decanoate) is dispersed in THF (tetrahydrofuran), and a 10-μm-thick lithiumophobic layer is prepared by spraying it onto the lithiumophilic layer; it is dried at room temperature in a vacuum oven to remove THF (tetrahydrofuran), and then the interfacial modification layer is densified by rolling to obtain the lithium metal negative electrode. To test the Coulombic efficiency, the interfacial modification layer is prepared on a Cu foil in the same manner.

[0022] The above-prepared lithium metal negative electrode is assembled into a Li symmetric battery and a Li||Cu battery to test its critical current density and Coulombic efficiency. The lithium salt in the electrolyte used is lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), the solvent is composed of DOL (dioxolane) and DME (ethylene glycol dimethyl ether) in a volume ratio of 1:1, and the concentration of the lithium salt in the solvent is 1 M. This electrolyte is 1 M LiTFSI@DOL / DME (1:1). The test results are shown in Table 1 below:

[0023] Table 1 Performance test results of the lithium metal negative electrode prepared in Example 1

[0024] Lithophilic layer Lithophobic layer Coulombic efficiency <![CDATA[Critical current density (mA / cm 2 )]]> Al LiF 99.1％ 7.1 Zn <![CDATA[Li3N]]> 99.4％ 6 Mg <![CDATA[Li2S]]> 99.9％ 5.5 As <![CDATA[Li2O]]> 99.2％ 7.4 Au LiCl 99.5％ 9.2 Ag LiBr 99.7％ 8.7 Ga LiI 99.92％ 5.1 Pb <![CDATA[Li2CO3]]> 99.1％ 4.7 Cd Lithium decanoate 99.7％ 4.5 Bi LiF 99.8％ 5.9 In <![CDATA[Li3N]]> 99.5％ 7.3 Ge <![CDATA[Li2S]]> 99.7％ 7.7 Sn <![CDATA[Li2O]]> 99.6％ 8.2 B LiCl 99.9％ 7.8

[0025] Example 2

[0026] In this embodiment, the lithium metal negative electrode with an interfacial modification layer includes a lithium metal negative electrode. The surface of the lithium metal negative electrode has an interfacial modification layer, and the interfacial modification layer sequentially includes a lithiumophobic layer and a lithiumophilic layer from the inside out. The structure of this lithium metal negative electrode is denoted as: lithium metal + lithiumophobic layer + lithiumophilic layer.

[0027] According to the material design corresponding to the lithiumophilic layer and the lithium-phobic layer in Table 2, a lithium-phobic substance powder (LiF, Li3N, Li2S, Li2O, LiCl, LiBr, LiI, Li2CO3 or lithium decanoate) is dispersed in a PEO (polyethylene oxide) polymer binder solution, and a 1-μm-thick lithium-phobic layer is prepared on the lithium metal by wet coating and dried at room temperature in a vacuum oven to remove THF; a lithiumophilic metal or non-metal element is chemically deposited on the lithium-phobic layer to prepare a 1-μm-thick lithiumophilic layer; then the interface modification layer is densified by isostatic pressing to obtain a lithium metal negative electrode. To test the Coulombic efficiency, an interface modification layer is prepared on a Cu foil by the same method.

[0028] The prepared lithium metal negative electrode is assembled into a Li symmetric battery and a Li||Cu battery to test its critical current density and Coulombic efficiency. The electrolyte used is the same as that in Example 1; the test results are shown in Table 2 below:

[0029] Table 2 Performance test results of the lithium metal negative electrode prepared in Example 2

[0030] Lithophilic layer Lithophobic layer Coulombic efficiency <![CDATA[Critical current density (mA / cm 2 )]]> Si LiBr 99.2％ 7.9 P LiI 99.7％ 7 Ti <![CDATA[Li2CO3]]> 99.3％ 5.5 V Lithium decanoate 99.8％ 4.9 Cr LiF 99.5％ 5.1 Mn <![CDATA[Li3N]]> 99.9％ 5.7 Co <![CDATA[Li2S]]> 99.6％ 2.9 Ni <![CDATA[Li2O]]> 99.9％ 2.8 Cu LiCl 99.5％ 2.1 Nb LiBr 99.2％ 2 Mo LiI 99％ 1.9 Ru <![CDATA[Li2CO3]]> 99.7％ 4

[0031] Example 3

[0032] In this example, the lithium metal negative electrode with an interface modification layer includes a lithium metal negative electrode. The surface of the lithium metal negative electrode has an interface modification layer, and the interface modification layer includes a lithiumophilic layer 1, a lithiumophilic layer 2, and a lithium-phobic layer in sequence from the inside out. The structure of this lithium metal negative electrode is denoted as: lithium metal + lithiumophilic layer 1 + lithiumophilic layer 2 + lithium-phobic layer.

[0033] According to the material design corresponding to the lithiumophilic layer and the lithium-phobic layer in Table 3, a lithiumophilic substance powder with high lithiumophilicity is dispersed in an epoxy resin monomer, and a 20-μm-thick lithiumophilic layer 1 is prepared on the lithium metal by screen printing and then cured by heating at 80 °C; a lithiumophilic substance powder with low lithiumophilicity is dispersed in a PVDF (polyvinylidene fluoride) polymer solution, and a 5-μm-thick lithiumophilic layer 2 is prepared on the lithiumophilic layer 1 by inkjet printing; a lithium-phobic substance powder is prepared into a 100-nm-thick lithium-phobic layer on the lithiumophilic layer 2 by electrostatic powder planting; then the interface modification layer is densified by flat pressing to obtain a lithium metal negative electrode. To increase the electronic conductivity of the lithiumophilic layer, a conductive agent, carbon nanotubes (mass fraction 0.1% - 10%), is added to the lithiumophilic layer 1, and a conductive agent, graphene (mass fraction 0.1% - 10%), is added to the lithiumophilic layer 2. To test the Coulombic efficiency, an interface modification layer is prepared on a Cu foil by the same method.

[0034] The prepared lithium metal anode was assembled into a Li symmetric battery and a Li||Cu battery to test its critical current density and Coulombic efficiency. The electrolyte used was the ceramic electrolyte Li3PS4. The test results are shown in Table 3 below:

[0035] Table 3 Performance test results of the lithium metal anode prepared in Example 3

[0036]

[0037] Example 4

[0038] In this example, the lithium metal anode with an interfacial modification layer includes a lithium metal anode, and the surface of the lithium metal anode has an interfacial modification layer. The interfacial modification layer sequentially includes a lithiumophilic layer 1, a lithiumophobic layer 1, a lithiumophilic layer 2, and a lithiumophobic layer 2 from the inside out. The structure of this lithium metal anode is denoted as: lithium metal + lithiumophilic layer 1 + lithiumophobic layer 1 + lithiumophilic layer 2 + lithiumophobic layer 2.

[0039] According to the materials corresponding to the lithiumophilic layer and the lithiumophobic layer designed in Table 4, the lithiumophilic substance powder with high lithium affinity was dispersed in the isocyanate monomer, and a 5-μm-thick lithiumophilic layer 1 was prepared on PET (polyethylene terephthalate) by doctor blade coating, and then cured by heating at 80 degrees; the lithiumophobic substance powder was dispersed in the PVDF polymer solution, and a 2-μm-thick lithiumophobic layer 1 was prepared on the lithiumophilic layer 1 by casting; the lithiumophilic substance powder with low lithium affinity was dispersed in the PVDF polymer solution, and a 2-μm-thick lithiumophilic layer 2 was prepared on the lithiumophobic layer 1 by spin coating; the lithiumophobic substance powder was dispersed in the PVDF polymer solution, and a 2-μm-thick lithiumophobic layer 2 was prepared on the lithiumophilic layer 2 by dipping; the thin sheet pre-prepared on PET was laminated with the lithium metal as the interfacial modification layer, and the modification layer was densified by stamping. To increase the electronic conductivity of the lithiumophilic layer, a conductive agent graphite (mass fraction 0.1% - 10%) was added to the lithiumophilic layer 1, and a conductive agent Super-P (mass fraction 0.1% - 10%) was added to the lithiumophilic layer 2. To test the Coulombic efficiency, the interfacial modification layer was prepared on the Cu foil in the same way.

[0040] The prepared lithium metal anode was assembled into a Li symmetric battery and a Li||Cu battery to test its critical current density and Coulombic efficiency. The electrolyte used was the same as that in Example 1. The test results are shown in Table 4 below:

[0041] Table 4 Performance test results of the lithium metal anode prepared in Example 4

[0042]

[0043]

[0044] Comparative Example 1

[0045] In this comparative example, the lithium metal anode with an interfacial modification layer includes a lithium metal anode, and the surface of the lithium metal anode has an interfacial modification layer, and the interfacial modification layer only includes a lithiumophilic layer. The structure of this lithium metal anode is denoted as: lithium metal + lithiumophilic layer.

[0046] According to the materials corresponding to the lithiumophilic layer in Table 5, a metal or non-metal element with lithiumophilicity is magnetron sputtered onto the lithium metal in bulk form to prepare a 100-nm-thick lithiumophilic layer. To test the Coulombic efficiency, an interfacial modification layer is prepared on the Cu foil in the same way.

[0047] The prepared lithium metal anode is assembled into a Li symmetric battery and a Li||Cu battery, and its critical current density and Coulombic efficiency are tested. The electrolyte used is the same as that in Example 1. The test results are shown in Table 5 below:

[0048] Table 5 Performance test results of the lithium metal anode prepared in Comparative Example 1

[0049]

[0050]

[0051] Comparative Example 2

[0052] In this comparative example, the lithium metal anode with an interfacial modification layer includes a lithium metal anode, and the surface of the lithium metal anode has an interfacial modification layer, and the interfacial modification layer only includes a lithium-phobic layer. The structure of this lithium metal anode is denoted as: lithium metal + lithium-phobic layer.

[0053] According to the materials corresponding to the lithium-phobic layer in Table 6, a powder with lithium-phobicity is dispersed in THF and sprayed onto the lithiumophilic layer to prepare a 10-μm-thick lithium-phobic layer; it is dried at room temperature in a vacuum oven to remove THF, and then the interfacial modification layer is densified by rolling. To test the Coulombic efficiency, an interfacial modification layer is prepared on the Cu foil in the same way.

[0054] The prepared lithium metal anode is assembled into a Li symmetric battery and a Li||Cu battery, and its critical current density and Coulombic efficiency are tested. The electrolyte used is the same as that in Example 1. The test results are shown in Table 6 below:

[0055] Table 6 Performance test results of the lithium metal anode prepared in Comparative Example 2

[0056] Lithophobic layer Coulombic efficiency <![CDATA[Critical current density (mA / cm 2 )]]> LiF 91.2％ 1.8 <![CDATA[Li3N]]> 90.3％ 1.1 <![CDATA[Li2S]]> 79.7％ 0.9 <![CDATA[Li2O]]> 80.3％ 0.7 LiCl 78.7％ 1.1 LiBr 75.7％ 1.2 LiI 77.1％ 0.7 <![CDATA[Li2CO3]]> 81.1％ 0.5 Lithium decanoate 55.1％ 0.7

[0057] Result analysis:

[0058] From the test results of the above embodiments and comparative examples, it can be seen that the lithiumophilic layer can guide the uniform and dense deposition of lithium metal, and the lithium-phobic layer has a high interfacial energy and is relatively stable to lithium metal. In addition, due to the difference in lithium metal affinity between the lithiumophilic layer and the lithium-phobic layer, there is a space charge layer at the interface between the two, and a solid electrolyte interface of the lithiumophilic layer / lithium-phobic layer is spontaneously formed during the charge and discharge process, which has the effect of protecting lithium metal and inhibiting lithium dendrites. During the charge and discharge process of the lithium metal battery, this interface modification layer can inhibit the formation of lithium dendrites, reduce side reactions, improve the Coulomb efficiency, and obtain uniform and dense deposition.

[0059] Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

Claims

1. A lithium metal anode with an interface modification layer, characterized in that: The surface of the lithium metal negative electrode has an interfacial modification layer, and the interfacial modification layer includes at least one layer of lithiumophilic layer and at least one layer of lithium-phobic layer; the lithiumophilic layer is an electron conductor, and the lithium-phobic layer is an ion conductor and an electron insulator; The number of layers of the lithiumophilic layer is multiple and the lithiumophilicity of each layer is different. The lithiumophilic layers are arranged in a gradient order from high to low in terms of lithiumophilicity, and the lithiumophilic layer with high lithiumophilicity is closer to the lithium metal negative electrode side; A conductive agent is added to the lithiumophilic layer; The lithium metal negative electrode is pure lithium metal or a lithium metal alloy.

2. The lithium metal negative electrode with an interface modification layer according to claim 1, characterized in that: The material of the lithiumophilic layer is selected from one or more of Al, Zn, Mg, As, Au, Ag, Ga, Pb, Cd, Bi, In, Ge, Sn, B, Si, P, Ti, V, Cr, Mn, Co, Ni, Cu, Nb, Mo, Ru, oxides, nitrides, sulfides, phosphides, halides, carbon materials; 3. The lithium metal anode with an interface modification layer according to claim 1, wherein: The conductive agent includes one or more of carbon nanotubes, graphene, graphite, carbon fiber, activated carbon, Super-P, carbon black; 4. The lithium metal negative electrode with an interface modification layer according to claim 1, characterized in that: The material of the lithium-phobic layer is selected from one or more of LiF, Li3N, Li2S, Li2O, LiCl, LiBr, LiI, Li2CO3, Li2SO4, LiNO3, Li2PO3, LiClO4, LiN(CF3SO2)2, LiN(FSO2)2, LiClO4, LiCF3SO3, LiBF4, LiPF4, LiAsF6, LiB(C2O4)2, lithium carboxylate, ceramic solid electrolyte, polymer electrolyte, ceramic / polymer composite electrolyte; 5. The lithium metal anode with an interfacial modification layer according to claim 1, characterized in that: The thickness of the lithiumophilic layer is 0.01~100 μm, and the thickness of the lithium-phobic layer is 0.01~100 μm.

6. The preparation method of the lithium metal negative electrode with an interface modification layer according to any one of claims 1 to 5, characterized in that: It includes the following steps: Just prepare an interfacial modification layer on the surface of the lithium metal negative electrode; the interfacial modification layer includes at least one layer of lithiumophilic layer and at least one layer of lithium-phobic layer.

7. The preparation method of the lithium metal negative electrode with an interface modification layer according to claim 6, characterized in that: The preparation methods of the lithiumophilic layer and the lithium-phobic layer in the interfacial modification layer include one or more of wet coating, screen printing, electrostatic powder implantation, spraying, casting, dipping, dropping, electroplating, physical deposition, chemical deposition, chemical reaction; 8. The preparation method of the lithium metal negative electrode with an interface modification layer according to claim 6, characterized in that: The preparation method of the lithiumophilic layer and the lithium-phobic layer in the interfacial modification layer is inkjet printing.

9. The preparation method of the lithium metal negative electrode with an interface modification layer according to claim 6, characterized in that: Disperse the materials for preparing the lithiumophilic layer and the materials for preparing the lithium-phobic layer in the matrix material respectively to form slurries; then load the slurries on the surface of the lithium metal negative electrode in sequence; the matrix material is one or more of a solvent, a polymer binder, a polymer monomer; the polymer monomer can be cured into a polymer.

10. The preparation method of the lithium metal negative electrode with an interface modification layer according to claim 6, characterized in that: Pre-prepare the materials for preparing the lithiumophilic layer and the materials for preparing the lithium-phobic layer into thin sheets respectively, and then laminate them with the lithium metal negative electrode to form an interfacial modification layer; the interfacial modification layer can be densified by applying pressure, and the pressure application method is at least one of flat static pressure, isostatic pressure, roll pressing and stamping.

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