CN-122025647-A - Three-dimensional composite material current collector for lithium-containing battery, preparation method of three-dimensional composite material current collector, lithium metal battery and lithium air battery

CN122025647ACN 122025647 ACN122025647 ACN 122025647ACN-122025647-A

Abstract

The invention relates to a three-dimensional composite material current collector for a lithium-containing battery, a preparation method of the three-dimensional composite material current collector, a lithium metal battery and a lithium air battery. The current collector is of a double-layer structure, one layer is of an electrode three-dimensional structure, the other layer is of a compact electrode structure, the electrode three-dimensional structure is provided with finger-shaped holes, the current collector comprises a conductive framework and a lithium-containing solid electrolyte, and the conductive framework comprises an alloy phase formed by high-conductivity metal and high-lithium metal affinity metal. The conductive framework and the solid electrolyte are tightly compounded in a three-dimensional space to form a continuous interpenetrating ion transmission channel and an electronic transmission channel, so that the interface impedance of the electrolyte and the current collector can be effectively reduced. The lithium air battery assembled by the current collector has obviously excellent electrochemical performance in the aspects of discharge capacity utilization rate, rate response capability and cycling stability, and has good engineering application potential.

Inventors

ZHANG KE
LI ZIYUAN
XIE ZHIFENG
HUANG XUDONG

Assignees

清华大学

Dates

Publication Date: 20260512
Application Date: 20260324

Claims (15)

1. The three-dimensional composite material current collector for the lithium-containing battery is characterized by being of a double-layer structure, wherein one layer is of an electrode three-dimensional structure, the other layer is of a compact electrode structure, and the electrode three-dimensional structure is provided with finger-shaped holes; The three-dimensional composite current collector includes a conductive backbone including an alloy phase formed of a high conductivity metal selected from one or more of Cu, ag, and Au and a high lithium metal affinity metal selected from one or more of Ni, co, cr, fe, ti, mo, W, sn and Al, and a lithium-containing solid electrolyte.
2. The three-dimensional composite current collector of claim 1, wherein the lithium-containing battery is a lithium metal battery or a lithium air battery.
3. The three-dimensional composite current collector according to claim 1 or 2, wherein the high-conductivity metal is Cu or a combination of Cu and any one of Ag and Au, and the high-lithium metal affinity metal is Ni or a combination of Ni and any one of Co, cr, fe, ti, mo, W, sn and Al; Preferably, the high conductivity metal is Cu, and the high lithium metal affinity metal is Ni, a combination of Ni and Co, or a combination of Ni and Cr; More preferably, the high conductivity metal is Cu and the high lithium metal affinity metal is Ni; Further, the alloy phase contains 40% -95% by mass of Cu and 5% -60% by mass of Ni, further preferably 70% -90% by mass of Cu and 10% -30% by mass of Ni, and most preferably the alloy phase is Cu 81 Ni 19 .
4. A three-dimensional composite collector according to any one of claims 1 to 3, wherein the alloy phase is a solid solution phase.
5. The three-dimensional composite current collector according to any one of claims 1 to 4, wherein the lithium-containing solid electrolyte comprises a garnet-type lithium-containing solid electrolyte; preferably, the lithium-containing solid electrolyte includes at least one of LLZTO, LLZO and derived lithium oxides thereof formed during high temperature sintering.
6. The three-dimensional composite current collector according to any one of claims 1 to 5, wherein the thickness of the three-dimensional composite current collector is 150 to 500 μm, and the aperture of the finger-shaped hole is 10 to 80 μm.
7. A method for preparing the three-dimensional composite current collector according to any one of claims 1 to 6, comprising the steps of: (1) Mixing and ball milling a lithium-containing solid electrolyte and at least two metal oxides to obtain functional powder; (2) Mixing and ball milling a solvent, a dispersing agent and an adhesive to obtain a mixed solution; (3) Mixing and ball milling the functional powder obtained in the step (1) and the mixed solution obtained in the step (2) to obtain slurry X; (4) Mixing and ball milling carbon powder, a solvent, a dispersing agent and an adhesive to obtain slurry Y; (5) A double-layer knife coating method is adopted, slurry X is coated on the surface of the thermoplastic polyester film strip in a knife manner on the upper layer and slurry Y is coated on the lower layer, and a blank body is obtained; (6) Placing the embryo body obtained in the step (5) into a flocculating agent, completing exchange of a solvent in the embryo body and the flocculating agent and solidification of the embryo body, and then drying; (7) Soaking the product obtained in the step (6) with an alcohol solution of lithium chloride, washing off redundant lithium chloride after the soaking is finished, and then drying; (8) Sintering the product obtained in the step (7) in an air atmosphere to remove carbon powder, solvent, dispersing agent, adhesive and thermoplastic polyester film tape; (9) Placing the product obtained in the step (8) in a sealed crucible in lithium carbonate atmosphere for sintering and molding; (10) And (3) reducing and sintering the product obtained in the step (9) by using hydrogen to obtain the three-dimensional composite material current collector.
8. The method according to claim 7, wherein in the step (1), each of the metal oxides includes particles of two sizes, and the lithium-containing solid electrolyte includes particles of two sizes; preferably, in the step (1), the functional powder comprises functional powder A and functional powder B, wherein the preparation method of the functional powder A comprises the steps of mixing and ball milling small-particle-size metal oxide and small-particle-size lithium-containing solid electrolyte to obtain the functional powder A, and the preparation method of the functional powder B comprises the steps of mixing and ball milling large-particle-size metal oxide and large-particle-size lithium-containing solid electrolyte to obtain the functional powder B.
9. The production method according to claim 8, wherein the large-size particles in each of the metal oxides have a particle size of 10 to 100 μm and the small-size particles have a particle size of 0.01 to 5 μm; preferably, the mass ratio of the large-particle-size particles to the small-particle-size particles in each metal oxide is 0.6:1-1.5:1.
10. The production method according to claim 8 or 9, wherein the large-particle-diameter particles in the lithium-containing solid electrolyte have a particle diameter of 50 to 500 μm and the small-particle-diameter particles have a particle diameter of 0.05 to 5 μm; preferably, the mass ratio of the large-particle-size particles to the small-particle-size particles in the lithium-containing solid electrolyte is 0.7:1-1.4:1.
11. The method of any one of claims 7 to 10, wherein the ratio of the total mass of the metal oxide to the mass of the lithium-containing solid electrolyte is 1:1 to 15:1, preferably 3:1 to 12:1, more preferably 8:1 to 10:1; further, the metal oxide comprises CuO and NiO, and the mass ratio of the CuO to the NiO is 0.5:1-15:1, preferably 0.8:1-10:1, and more preferably 2:1-5:1.
12. The method for producing a ceramic foam according to any one of claims 7 to 11, The carbon powder is graphite or carbon black; the solvent is N-methyl pyrrolidone or 3-methoxyl butyl acetate; the dispersing agent is polyvinylpyrrolidone, polyvinyl alcohol or chitosan; the adhesive is polyphenyl ether sulfone, polyvinylidene fluoride or polyacrylonitrile; The flocculating agent is water, ethanol or acetone.
13. The method for preparing the polymer according to any one of claim 7 to 12, wherein, The temperature of the drying in the step (6) is 60-80 ℃; the temperature of the drying in the step (7) is 60-80 ℃; the sintering temperature in the step (8) is 700-900 ℃; The sintering temperature in the step (9) is 800-1000 ℃; The sintering temperature in the step (10) is 500-800 ℃.
14. The lithium-rich negative electrode is characterized by comprising the three-dimensional composite material current collector disclosed in any one of claims 1-6 or the three-dimensional composite material current collector prepared by the preparation method disclosed in any one of claims 7-13 and lithium metal loaded on the three-dimensional composite material current collector.
15. A lithium metal battery or a lithium air battery, characterized in that the lithium metal battery or the lithium air battery comprises the three-dimensional composite material current collector according to any one of claims 1 to 6, the three-dimensional composite material current collector prepared by the preparation method according to any one of claims 7 to 13, or the lithium-rich negative electrode according to claim 14.

Description

Three-dimensional composite material current collector for lithium-containing battery, preparation method of three-dimensional composite material current collector, lithium metal battery and lithium air battery Technical Field The invention belongs to the technical field of lithium air batteries, relates to a three-dimensional composite material current collector for a lithium-containing battery based on multiphase cooperation and interface engineering and a preparation method thereof, and simultaneously relates to a lithium metal battery and a lithium air battery containing the three-dimensional composite material current collector. Background Lithium air batteries, which use ambient or supplied oxygen as the source of positive electrode active material, have extremely high theoretical specific energy, and are considered to be an important development direction for next-generation high specific energy storage systems. However, lithium-air battery systems still face the problems of insufficient reaction reversibility, complex side reactions, limited cycle life, and the like in the actual chargeable process. The prior research and technical development work is mainly focused on the directions of an anode air electrode (such as a catalyst system, a pore structure, product deposition regulation and control and the like), an electrolyte system, interface stability and the like. It should be noted that the electrochemical reaction process of the lithium air battery is not solely determined by the positive electrode air electrode, but is an integral reaction system formed by the positive electrode, the negative electrode and the electrolyte system. In a lithium air battery, the deposition and stripping actions of lithium at the negative electrode side directly determine the stability of a reversible lithium source in the system, and the interface state of the lithium air battery affects key performance indexes such as the effective capacity utilization rate, the coulomb efficiency, the cycle life and the like of the battery. Therefore, although lithium-air batteries have uniqueness in reaction mechanism, characterized by air electrodes, the negative electrode structure and interfacial stability are one of the fundamental factors that limit the overall performance and engineering feasibility of the battery. In conventional lithium-air battery configurations, the negative electrode typically employs a lithium foil directly as the negative electrode active material and the electron-conducting carrier. The structure is simple, but the problems of uneven interface contact, morphology evolution, aggravation of local reaction and the like are easy to occur in the processing, assembling and circulating processes, and meanwhile, the lithium foil consumption is large, so that the lightweight design and the large-scale manufacturing of a battery system are not facilitated. In order to solve the above problems, in recent years, a negative electrode configuration concept has been developed in which a thick lithium foil is replaced with a negative electrode current collector or carrier, lithium metal is deposited on the surface of the current collector by pre-lithiation or electrochemical means, and then battery assembly is performed. The configuration realizes the controllable introduction of lithium metal on the current collector, has consistency with a non-negative electrode or lithium carrying system on an engineering target, is beneficial to reducing the effective current density, improving the lithium deposition uniformity and improving the designability and manufacturability of a negative electrode structure. For example, patent application CN116979065A discloses a method for preparing copper current collector with "step" structure for inducing lithium metal to grow inwards, by laser etching technology, a low-power multiple bombardment processing method is adopted, layered nano structure is introduced into the inner wall of micro pits by colleagues preparing distributed micro pit arrays, and structural hierarchy and roughness are increased, so that lithium metal is induced to deposit on the inner wall of micro pits, the metal lithium deposition and precipitation process has better electrochemical stability, and the obtained copper current collector has higher coulomb efficiency and can be used for assembling lithium air batteries. In the negative electrode configuration of the lithium deposited on the current collector/carrier, the current collector not only bears the functions of electron transmission and structural support, but also directly serves as a physical and chemical carrier in the nucleation, growth and stripping processes of lithium metal, and the surface chemical state, the three-dimensional structure morphology, the pore channel characteristics and the interface contact quality with electrolyte have important influences on lithium deposition behaviors, interface impedance evolution and cycle reversibility.