Lithium battery with high energy density and long service life and preparation method thereof

Abstract

The invention provides a high-energy-density long-life lithium battery and a preparation method thereof, a negative electrode material of the high-energy-density long-life lithium battery comprises a pre-lithiation material, and the pre-lithiation material comprises metal lithium and a Mn3O4-graphene oxide composite material. The negative electrode material has extremely high first coulombic efficiency, good energy density, excellent cycle performance and relatively high specific capacity.

Description

Technical Field

[0001] The present invention belongs to the field of lithium batteries, and particularly relates to a long-life lithium battery with high energy density and a preparation method thereof. Background Art

[0002] Due to the rise of mobile devices, electric vehicles and some other electric devices, energy storage devices have attracted more and more attention. Among them, due to their high energy density and good cycling performance, lithium batteries have attracted great attention from scientists, which has also led to the great development of lithium batteries in recent years. However, with the increasing number of high-energy-consuming devices, the traditional graphite anode of lithium batteries (372 mAh / g) can no longer meet people's needs. Therefore, alternative anode materials with large capacity have received more and more attention.

[0003] As high specific capacity anode materials, manganese tetroxide and silicon-based materials have great potential. Although the problem of poor stability caused by their huge volume expansion can be solved by designing nanostructures, the problem of low initial charge-discharge Coulomb efficiency of such materials has not been effectively solved. Therefore, designing a treatment method that can improve the initial charge-discharge Coulomb efficiency of lithium batteries is the key to bringing such materials to the market. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention provides a long-life lithium battery with high energy density and a preparation method thereof. The lithium battery prepared by the long-life lithium battery with high energy density provided by the present invention can be used normally in a wide temperature environment, broadening the application field of lithium batteries.

[0005] To achieve the above object, the present invention adopts the following technical solutions: On the one hand, the present application provides a long-life lithium battery with high energy density. The anode material of the lithium battery includes a prelithiated material, and the prelithiated material includes metallic lithium and a Mn3O4-graphene oxide composite material.

[0006] Further, the anode material of the lithium battery further includes a binder, a conductive agent, and an active substance; Further, the binder includes one or more of polyvinylidene fluoride, sodium carboxymethyl cellulose, styrene-butadiene rubber, polyacrylic acid, polytetrafluoroethylene, and polyimide; Further, the conductive agent includes one or more of SuperP, acetylene black, conductive graphite, vapor-grown carbon fiber, carbon nanotube, and graphene; Further, the active substance includes one or more of silicon-oxygen materials, tin-nickel alloys, and silicon-carbon materials.

[0007] Further, the mass ratio of the binder, conductive agent, active material to the prelithiation material is 1 - 3:3 - 5:90 - 110:1 - 20; Preferably, the mass ratio of the binder, conductive agent, active material to the prelithiation material is 2:4:100:1 - 20; More preferably, the mass ratio of the binder, conductive agent, active material to the prelithiation material is 2:4:100:5 - 15; Further, the preparation method of the prelithiation material includes: taking graphene oxide and uniformly dispersing it in deionized water, adding ethanol, then slowly dropping a KMnO₄ solution into the graphene oxide solution, stirring and then standing, and then heating the separated solid intermediate in an inert atmosphere to obtain a Mn₃O₄ - graphene oxide composite material, and then adding metallic lithium and the Mn₃O₄ - graphene oxide composite material into a heater for heating, stirring evenly, and then cooling to room temperature to obtain the prelithiation material; Further, the specific steps for preparing the Mn₃O₄ - graphene oxide composite material in step (1) are: taking graphene oxide, uniformly dispersing it in deionized water by ultrasonic treatment, then adding ethanol and stirring for 10 - 60 min, then slowly dropping the KMnO₄ solution into the graphene oxide solution, continuing to stir for 8 - 16 h and then standing for 3 - 7 h, centrifuging, washing and freeze - drying, and then heating the freeze - dried intermediate in an argon atmosphere to 350 - 400 °C, holding for reaction for 1 - 4 h to obtain the Mn₃O₄ - graphene oxide composite material; Further, the mass ratio of graphene oxide to KMnO₄ is 1:1 - 3, 1:1.5 - 2.5; Further, the mass - to - volume ratio of graphene oxide to deionized water is 1 - 4 g:1 L, 1 - 3 g:1 L; Further, the volume ratio of deionized water to ethanol is 2 - 6:1; Further, the concentration of the KMnO₄ solution is 10 - 40 g / L, 10 - 30 g / L or 15 - 25 g / L; Further, heating the freeze - dried intermediate in an argon atmosphere to 370 - 380 °C; Further, the mass ratio of metallic lithium to the Mn₃O₄ - graphene oxide composite material is 1 - 3:1; Further, the heating temperature for adding metallic lithium and the Mn₃O₄ - graphene oxide composite material into the heater for heating is 200 - 250 °C, and stirring for 5 - 30 min; Further, the lithium battery also includes an electrolyte, a positive electrode and a separator; Optionally, the electrolyte includes one or more of dimethyl carbonate, diethyl carbonate, and ethylene carbonate; the separator includes one or more of a PP / PE separator, a polyethylene terephthalate separator, a poly(p-phenylene benzobisoxazole) separator, a polyimide separator, a modified glass fiber membrane, a coated separator, and an electrospun separator; the material of the positive electrode includes one or more of lithium foil, lithium iron phosphate, lithium cobaltate, lithium nickel cobalt manganese oxide, and lithium manganate. Optionally, the lithium battery further includes a housing, and the material of the housing is selected from aluminum alloy, steel, aluminum plastic film, and sheet molding compound composite material.

[0008] On the other hand, the present application also provides a method for preparing a long-life lithium battery with high energy density, including the following steps: (1) Prepare a prelithiation material: Take graphene oxide and disperse it evenly in deionized water, add ethanol, then slowly drop a KMnO4 solution into the graphene oxide solution, stir and then let it stand. Then heat the separated solid intermediate in an inert atmosphere to obtain a Mn3O4-graphene oxide composite material. Then add metallic lithium and the Mn3O4-graphene oxide composite material to a heater for heating, stir evenly, and then cool to room temperature to obtain the prelithiation material; Among them, the inert atmosphere is one or more of an argon atmosphere, a nitrogen atmosphere, and a helium atmosphere; (2) Prepare a negative electrode sheet: Take a binder, a conductive agent, an active substance, and the prelithiation material, grind them, extrude the uniformly dispersed material into a film at a high temperature, and then laminate the obtained film on a current collector to obtain a negative electrode sheet; (3) Prepare a lithium battery: Use the negative electrode sheet described in step (2) as the negative electrode to prepare the lithium battery.

[0009] Further, the specific steps for preparing the Mn3O4-graphene oxide composite material in step (1) are as follows: Take graphene oxide, disperse it evenly in deionized water by ultrasonic treatment, then add ethanol and stir for 10 - 60 min, then slowly drop the KMnO4 solution into the graphene oxide solution, continue to stir for 8 - 16 h and then let it stand for 3 - 7 h, centrifuge, wash, and freeze-dry. Then heat the freeze-dried intermediate in an argon atmosphere to 350 - 400 °C and hold for 1 - 4 h to obtain the Mn3O4-graphene oxide composite material; Further, the mass ratio of graphene oxide to KMnO4 is 1:1 - 3; Further, the mass-volume ratio of graphene oxide to deionized water is 1 - 4 g:1 L; Further, the volume ratio of deionized water to ethanol is 2 - 6:1; Further, the concentration of the KMnO4 solution is 10 - 40 g / L; Further, heat the freeze-dried intermediate to 370 - 380 °C under an argon atmosphere; Further, the mass ratio of the metallic lithium to the Mn3O4-graphene oxide composite material is 1 - 3:1; Further, the heating temperature for then adding the metallic lithium and the Mn3O4-graphene oxide composite material into a heater for heating is 200 - 250 °C, and stir for 5 - 30 min; Further, the specific steps in step (2) are as follows: Weigh each substance according to the mass ratio of the binder, conductive agent, active material to the prelithiation material being 1 - 3:3 - 5:90 - 110:1 - 20, grind, extrude the uniformly dispersed materials into a film at high temperature, and then laminate the obtained film on a current collector to obtain a negative electrode sheet; Preferably, the mass ratio of the binder, conductive agent, active material to the prelithiation material is 2:4:100:1 - 20; More preferably, the mass ratio of the binder, conductive agent, active material to the prelithiation material is 2:4:100:5 - 15; Optionally, the current collector is one of a copper foil current collector, a stainless steel current collector, an aluminum foil current collector, a copper mesh, a carbon-coated copper foil / copper mesh, and a foamed copper.

[0010] Further, use the negative electrode sheet prepared by step (2) as the negative electrode, use a Li sheet as the positive electrode, select LiPF6 as the solute, and an organic solution prepared from dimethyl carbonate, diethyl carbonate, and ethylene carbonate with a volume ratio of 1:1:1 as the solvent, and a commercial PP / PE separator as the separator to prepare the lithium battery.

[0011] On the other hand, the present invention also provides a long-life lithium battery with a high energy density, which is prepared by the above preparation method.

[0012] Advantages of the present invention: The present invention provides a long-life lithium battery with a high energy density and a preparation method thereof. Among them, the negative electrode material of the long-life lithium battery with a high energy density includes a prelithiation material, and the prelithiation material includes metallic lithium and an Mn3O4-graphene oxide composite material. This negative electrode material has an extremely high initial Coulomb efficiency, good energy density, excellent cycle performance, rate performance, and relatively high specific capacity.

[0013] Based on the co - design of a composite anode material of metallic lithium and Mn3O4 - graphene oxide (Mn3O4 - GO), the significant improvement in its comprehensive performance may lie in the synergistic effect among various materials. First, through the prelithiation strategy to directly compensate for the first - cycle lithium loss and combined with the formation of a dense SEI film on the surface of GO, the first - cycle Coulombic efficiency is increased to over 98.6%, breaking through the efficiency bottleneck of traditional high - capacity materials. Second, due to the synergistic effect of the ultra - high theoretical capacity of metallic lithium (3860 mAh / g) and the multi - electron reaction characteristics of Mn3O4 (theoretical capacity 936 mAh / g), the energy density and specific capacity are greatly improved. At the same time, the three - dimensional conductive network and nano - confinement effect of GO provide an efficient electron transport channel for the active material, and inhibit the growth of lithium dendrites and volume expansion, ensuring cycle stability. In addition, the short - range ion diffusion path of Mn3O4 nanoparticles and the charge - transfer acceleration effect at the hetero - interface of GO jointly optimize the rate performance. Through the multi - dimensional synergy of component regulation, structure strengthening, and interface optimization, this material system not only solves the problems of volume expansion and low efficiency of high - capacity anodes, but also provides an innovative path for the practical application of the next - generation high - energy - density and long - life lithium batteries, showing broad application prospects. Detailed implementation manners

[0014] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this invention belongs. The terms used in the specification of this invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. In the description of this application, it should be understood that "and / or" describes the association relationship of associated objects and indicates that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. Where A and B can be singular or plural. In this application, "at least one" means one or more, and "a plurality" means two or more. "At least one kind", "at least one item (piece) below" or similar expressions refer to any combination of these items, including any combination of single item (piece) or plural items (pieces). For example, "at least one item (piece) among a, b, or c", or, "at least one item (piece) among a, b, and c" can all represent: a, b, c, a - b (that is, a and b), a - c, b - c, or a - b - c, where a, b, and c can be single or multiple respectively.

[0016] Example 1 This example provides a long - life lithium battery with high energy density and its preparation method. The specific steps are as follows: (1)Prepare the prelithiated material. Take 8 g of graphene oxide, disperse it evenly in 4 L of deionized water by ultrasonic treatment, then add 1 L of ethanol and stir for 30 min. Then slowly drop 0.2 L of KMnO₄ solution (20 g / L) into the graphene oxide solution, continue to stir for 12 h, then let it stand for 5 h, centrifuge, wash and freeze - dry. Then heat the freeze - dried intermediate to 375 °C in an argon atmosphere and keep it for 2 h to obtain the Mn₃O₄ - graphene oxide composite material; Add 10 g of battery - grade metallic lithium and 5 g of the Mn₃O₄ - graphene oxide composite material into a heater with a stainless - steel reactor, heat to 230 °C, stir for 20 min, the stirring speed is 500 r / min, and cool to room temperature to obtain the prelithiated material; (2)Prepare the negative electrode sheet. Weigh each substance according to the ratio of polytetrafluoroethylene: acetylene black (Jiaozuo Hexing Chemical Industry Co., Ltd.): silicon carbide: prelithiated material = 2 g: 4 g: 100 g: 10 g, place them in a small jet mill and grind for 2 h. Extrude the uniformly dispersed material into a film at high temperature. The thickness of the electrode film is 90 μm, and then use a roll press to compound it on a copper foil current collector with a thickness of 8 μm. Then cut the obtained electrode sheet into shape to be used as the negative electrode sheet of the prelithiated lithium battery; (3)Prepare the lithium battery. Use the negative electrode sheet prepared in step (2) as the negative electrode, use a Li sheet as the positive electrode, select LiPF₆ as the solute, and an organic solution prepared from dimethyl carbonate, diethyl carbonate and ethylene carbonate with a volume ratio of 1:1:1 as the electrolyte, and a commercial PP / PE separator to prepare the lithium battery.

[0017] Example 2 This example provides a long - life lithium battery with high energy density and its preparation method. The specific steps are as follows: (1)Prepare the prelithiated material. Take 8 g of graphene oxide, disperse it evenly in 4 L of deionized water by ultrasonic treatment, then add 1 L of ethanol and stir for 30 min. Then slowly drop 0.2 L of KMnO₄ solution (20 g / L) into the graphene oxide solution, continue to stir for 12 h, then let it stand for 5 h, centrifuge, wash and freeze - dry. Then heat the freeze - dried intermediate to 375 °C in an argon atmosphere and keep it for 2 h to obtain the Mn₃O₄ - graphene oxide composite material; Add 10 g of battery - grade metallic lithium and 5 g of the Mn₃O₄ - graphene oxide composite material into a heater with a stainless - steel reactor, heat to 230 °C, stir for 20 min, the stirring speed is 500 r / min, and cool to room temperature to obtain the prelithiated material; (2)Preparation of the negative electrode sheet Weigh each substance according to the ratio of polytetrafluoroethylene: acetylene black: silicon carbide: prelithiation material = 2 g: 4 g: 100 g: 5 g, place them in a small jet mill and grind for 2 h. Extrude the uniformly dispersed material into a film at high temperature. The thickness of the electrode film is 90 microns, and then it is pressure-compounded on a copper foil current collector using a roll press. The thickness of the copper foil is 8 microns. Then, cut the obtained electrode sheet into the desired shape to obtain the negative electrode sheet of the prelithiated lithium battery. (3)Preparation of the lithium battery Use the negative electrode sheet prepared in step (2) as the negative electrode, use a Li sheet as the positive electrode, select LiPF6 as the solute, and use an organic solution prepared from dimethyl carbonate, diethyl carbonate, and ethylene carbonate with a volume ratio of 1:1:1 as the electrolyte. The separator is a commercial PP / PE separator to prepare the lithium battery.

[0018] Example 3 This example provides a high-energy-density long-life lithium battery and its preparation method. The specific steps are as follows: (1)Preparation of the prelithiation material Take 8 g of graphene oxide, disperse it evenly in 4 L of deionized water by ultrasonic treatment, then add 1 L of ethanol and stir for 30 min. Then, slowly drop 0.2 L of KMnO4 solution (20 g / L) into the graphene oxide solution, continue to stir for 12 h, then let it stand for 5 h. Centrifuge, wash, and freeze-dry. Then, heat the freeze-dried intermediate to 375 °C in an argon atmosphere and keep it at this temperature for 2 h to obtain the Mn3O4-graphene oxide composite material. Add 10 g of battery-grade metallic lithium and 5 g of the Mn3O4-graphene oxide composite material to a heater with a stainless steel autoclave, heat to 230 °C, stir for 20 min at a stirring speed of 500 r / min, and cool to room temperature to obtain the prelithiation material. (2)Preparation of the negative electrode sheet Weigh each substance according to the ratio of polytetrafluoroethylene: acetylene black: silicon carbide: prelithiation material = 2 g: 4 g: 100 g: 15 g, place them in a small jet mill and grind for 2 h. Extrude the uniformly dispersed material into a film at high temperature. The thickness of the electrode film is 90 microns, and then it is pressure-compounded on a copper foil current collector using a roll press. The thickness of the copper foil is 8 microns. Then, cut the obtained electrode sheet into the desired shape to obtain the negative electrode sheet of the prelithiated lithium battery. (3)Preparation of the lithium battery Use the negative electrode sheet prepared in step (2) as the negative electrode, use a Li sheet as the positive electrode, select LiPF6 as the solute, and use an organic solution prepared from dimethyl carbonate, diethyl carbonate, and ethylene carbonate with a volume ratio of 1:1:1 as the electrolyte. The separator is a commercial PP / PE separator to prepare the lithium battery.

[0019] Comparative Example 1 Compared with Example 1, the only difference is that step (1) is omitted, that is, only polytetrafluoroethylene, acetylene black, and silicon carbide are added in step (2), and no prelithiation material is added.

[0020] Comparative Example 2 Compared with Example 1, the difference is only that: the Mn3O4-graphene oxide composite material in step (1) is directly used in step (2), that is, the compounding step of metallic lithium and the Mn3O4-graphene oxide composite material is omitted in step (1).

[0021] Test and analysis (1) First charge-discharge and charge-discharge cycle tests: The first charge-discharge and charge-discharge cycle tests were carried out on the prepared prelithiated lithium battery using a soft-pack test instrument, and the test voltage window was 3-4.2V; The first efficiency (initial Coulombic efficiency, ICE) is defined as: the ratio of the first discharge capacity to the first charge capacity, that is: First efficiency = first discharge capacity / first charge capacity × 100%. The results are shown in Table 1.

[0022] (2) The lithium batteries prepared in Examples 1-3 and Comparative Examples 1-2 were subjected to a room-temperature constant-current charge-discharge performance test. The test method was: a room-temperature constant-current charge-discharge test was carried out at 1C in the range of 3-4.2V, and the evaluation method was the capacity retention rate until the capacity retention rate was lower than 80%.

[0023] The capacity retention rate is defined as: capacity retention rate = discharge capacity of the nth cycle / discharge capacity of the first cycle × 100%, where n is the number of cycles. The calculation results were averaged, and the results are shown in Table 1.

[0024] Table 1 Initial efficiency Stable cycle (80% capacity retention) 1C discharge specific capacity (mAh / g) Example 1 100.8% 1760 times 498 Example 2 98.6% 1625 times 483 Example 3 99.5% 1690 times 489 Comparative example 1 90.6% 781 times 178 Comparative example 2 91.4% 872 times 297 It can be seen from the above experimental results that: the initial efficiency of the silicon-carbon electrode without prelithiation is only up to 90.6% at most, while after prelithiation, the initial efficiency can reach more than 98.6%, which has an obvious effect of improving the initial efficiency. In addition, from the stable cycle times and 1C discharge specific capacities of Examples 1-3 and Comparative Examples 1-2, it can be seen that: the lithium battery provided by the present application also has good energy density, excellent cycle performance, rate performance, and relatively high specific capacity, etc.

[0025] The above has introduced in detail a high-energy-density long-life lithium battery and its preparation method provided by the present application. Specific examples are used herein to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the technical solution and its core idea of the present application; those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A long-life lithium battery with high energy density, characterized in that, The negative electrode material of the lithium battery includes a prelithiated material, and the prelithiated material includes metallic lithium and an Mn3O4-graphene oxide composite material.

2. The long-life lithium battery with high energy density according to claim 1, wherein The negative electrode material of the lithium battery further includes a binder, a conductive agent, and an active material.

3. The high-energy-density long-life lithium battery according to claim 2, characterized in that, The mass ratio of the binder, the conductive agent, the active material to the prelithiated material is 1-3:3-5:90-110:1-20; The binder includes one or more of polyvinylidene fluoride, sodium carboxymethyl cellulose, styrene-butadiene rubber, polyacrylic acid, polytetrafluoroethylene, and polyimide; The conductive agent includes one or more of SuperP, acetylene black, conductive graphite, vapor-grown carbon fiber, carbon nanotube, and graphene; The active material includes one or more of silicon-oxygen material, tin-nickel alloy, and silicon-carbon material.

4. The high-energy density long-life lithium battery according to claim 1, wherein, The lithium battery further includes an electrolyte, a positive electrode, and a separator; the electrolyte includes one or more of dimethyl carbonate, diethyl carbonate, and ethylene carbonate, the separator includes one or more of a PP / PE separator, a polyethylene terephthalate separator, a poly(p-phenylene benzobisoxazole) separator, a polyimide separator, a modified glass fiber membrane, a coated separator, and an electrospun separator, and the material of the positive electrode includes one or more of a lithium sheet, lithium iron phosphate, lithium cobaltate, lithium nickel cobalt manganate, and lithium manganate; And / or, the lithium battery further includes a housing, and the material of the housing is selected from aluminum alloy, steel, aluminum plastic film, and sheet molding compound composite material.

5. A preparation method of a long-life lithium battery with high energy density, characterized in that, It includes the following steps: (1) Prepare the prelithiated material: Take graphene oxide and uniformly disperse it in deionized water, add ethanol, and then slowly drop a KMnO4 solution into the graphene oxide solution, stir and then let it stand, and then heat the separated solid intermediate in an inert atmosphere to obtain an Mn3O4-graphene oxide composite material, and then add metallic lithium and the Mn3O4-graphene oxide composite material to a heater for heating, stir evenly, and then cool to room temperature to obtain the prelithiated material; (2) Prepare the negative electrode sheet: Take the binder, the conductive agent, the active material, and the prelithiated material, grind them, extrude the uniformly dispersed materials into a film at a high temperature, and then laminate the obtained film on a current collector to obtain the negative electrode sheet; (3) Prepare the lithium battery: Use the negative electrode sheet described in step (2) as the negative electrode to prepare the lithium battery.

6. The preparation method of the long-life lithium battery with high energy density according to claim 5, characterized in that, The specific steps for preparing the Mn3O4-graphene oxide composite material in step (1) are: Take graphene oxide, uniformly disperse it in deionized water by ultrasonic treatment, then add ethanol and stir for 10-60 min, then slowly drop the KMnO4 solution into the graphene oxide solution, continue to stir for 8-16 h and then let it stand for 3-7 h, centrifuge, wash, and freeze-dry, and then heat the freeze-dried intermediate to 350-400 °C in an argon atmosphere and hold for 1-4 h to obtain the Mn3O4-graphene oxide composite material.

7. The preparation method of the long-life lithium battery with high energy density according to claim 5, characterized in that, The mass ratio of the graphene oxide to the KMnO4 is 1:1-3; The mass-volume ratio of the graphene oxide to the deionized water is 1-4 g:1 L; The volume ratio of the deionized water to the ethanol is 2-6:1; The concentration of the KMnO4 solution is 10-40 g / L.

8. The preparation method of the long-life lithium battery with high energy density according to claim 5, characterized in that, The mass ratio of the metallic lithium and the Mn3O4-graphene oxide composite material is 1-3:1; And / or, the heating temperature for heating the metallic lithium and the Mn3O4-graphene oxide composite material in a heater is 200-250 °C, and stirring is carried out for 5-30 min.

9. The preparation method of the long-life lithium battery with high energy density according to claim 5, characterized in that, The specific steps in the step (2) are as follows: Weigh each substance according to the mass ratio of the binder, the conductive agent, the active material to the prelithiation material being 1-3:3-5:90-110:1-20, grind, extrude the uniformly dispersed materials into a film at high temperature, and then laminate the obtained film on a current collector to obtain a negative electrode sheet; The current collector is one of a copper foil current collector, a stainless steel current collector, an aluminum foil current collector, a copper mesh, a carbon-coated copper foil / copper mesh, and foamed copper.

10. The preparation method of the long-life lithium battery with high energy density according to claim 5, characterized in that, Using the negative electrode sheet prepared in step (2) as the negative electrode, using a Li sheet as the positive electrode, selecting LiPF6 as the solute, and using an organic solution prepared from dimethyl carbonate, diethyl carbonate, and ethylene carbonate with a volume ratio of 1:1:1 as the electrolyte, and using a commercial PP / PE separator, the lithium battery is prepared.