CN-121983549-A - Sodium metal anode material with three-dimensional gradient sodium-philic interface and preparation method and application thereof

CN121983549ACN 121983549 ACN121983549 ACN 121983549ACN-121983549-A

Abstract

The invention discloses a sodium metal anode material with a three-dimensional gradient sodium-philic interface, and a preparation method and application thereof, and belongs to the technical field of sodium metal batteries. According to the invention, the sodium-philic metal with concentration gradient is coated on the metal mesh by an electrodeposition method, and then the metal mesh is coated on the surface of the sodium metal, so that the sodium metal negative electrode with the three-dimensional gradient sodium-philic interface can be obtained, the sodium metal negative electrode material has the three-dimensional gradient sodium-philic interface, the metal sodium can be guided to realize uniform and compact deposition from bottom to top, the large specific surface area is conducive to reducing local current density, sufficient space reserved by the metal mesh can realize high-capacity sodium ion deposition, meanwhile, the volume expansion and structural failure of the electrode are avoided, and the dendritic crystal-free growth and the excellent cycle life of the sodium metal negative electrode are finally realized. The invention has the characteristics of simple preparation process and low preparation environment requirement.

Inventors

WANG YINGYING
CHEN HUAN
HOU BAOHUA
Zhao Chenshuo

Assignees

郑州大学

Dates

Publication Date: 20260505
Application Date: 20260206

Claims (10)

1. The preparation method of the sodium metal anode material with the three-dimensional gradient sodium-philic interface is characterized by comprising the following steps of: And placing the cleaned metal mesh precursor into a prepared electrodeposition solution for electrodeposition, and washing and drying the obtained product to cover the sodium metal surface to obtain the sodium metal anode material with the three-dimensional gradient sodium-philic interface.
2. The method of claim 1, wherein the washing is performed with acetone, hydrochloric acid, deionized water or ethanol.
3. The method according to claim 2, wherein the metal mesh precursor is selected from any one of copper mesh, nickel mesh and stainless steel mesh, and has a mesh number of 200-500 mesh.
4. The method according to claim 3, wherein the solute in the electrodeposition solution is at least one selected from SbCl 3 、SnCl 4 、BiCl 3 and AgCl, and the solvent is ethanol or water at a concentration of 0.001-5mol/L.
5. The method of claim 4, wherein the electrodeposition conditions are constant voltage or constant current, the constant voltage is-10 to-0.01V, the constant current is 0.01 to 5A cm -2 , and the electrodeposition time is 1 to 30min.
6. The method according to claim 5, wherein the washing solution is a mixed solution of water and ethanol, and the drying temperature is 25-80 ℃.
7. The method of claim 6, wherein the coating is performed by coating the sodium metal surface with a side of the metal mesh having a high concentration of sodium-philic metal.
8. A sodium metal negative electrode material with a three-dimensional gradient sodium-philic interface prepared by the preparation method of any one of claims 1-7.
9. The use of the sodium-metal negative electrode material with three-dimensional gradient sodium-philic interface as claimed in claim 8 in preparing a negative electrode of a sodium-metal battery.
10. A sodium metal battery comprises a positive electrode, a negative electrode, a diaphragm and electrolyte, and is characterized in that the negative electrode is made of the sodium metal negative electrode material with the three-dimensional gradient sodium-philic interface according to claim 8.

Description

Sodium metal anode material with three-dimensional gradient sodium-philic interface and preparation method and application thereof Technical Field The invention belongs to the technical field of sodium metal batteries, and particularly relates to a preparation method and application of a sodium metal negative electrode material. Background With the rapid development of the fields of electric vehicles, portable and wearable devices, etc., the demand for high-efficiency energy storage is continuously increasing. Currently, lithium ion batteries are widely used due to their high energy density, low self-discharge rate, and long cycle life. However, lithium resources are limited and distributed unevenly throughout the world, resulting in higher cost of lithium ion batteries. Sodium and lithium belong to the same main group, have similar chemical properties, have abundant sodium reserves and are low in cost, so that the sodium ion battery is regarded as a very promising alternative for the lithium ion battery. Among the negative electrode materials of sodium ion batteries, hard carbon has received attention because of its low cost and good rate capability, but its lower specific capacity limits further increases in battery energy density. In contrast, sodium metal anodes have extremely high theoretical specific capacities (about 1165 mAh g -1) and lower redox potentials (-2.714V vs. SHE), making sodium metal batteries an important development direction for next generation high energy density energy storage systems. However, sodium metal anodes still present challenges in practical applications. During circulation, uneven sodium ion flux distribution and significant volume expansion can cause uneven, non-dense sodium deposition, thereby inducing sodium dendrite growth or "dead sodium" formation. These problems can significantly reduce coulomb efficiency, shorten cycle life, and even cause internal shorting of the battery, leading to safety hazards. To address the above problems, researchers have proposed various strategies including constructing three-dimensional current collectors, optimizing electrolyte systems, and developing interface engineering, among others. The interface engineering can effectively increase the specific surface area, reduce the local current density and promote the uniform deposition of sodium ions by constructing a three-dimensional interface interlayer on the surface of the electrode, and is widely focused due to simple and convenient operation. However, most of the three-dimensional interface interlayers reported at present are uniform conductors, sodium is easy to be deposited preferentially at the top end during rapid deposition, and then volume expansion is generated, dendrite growth is induced, so that interface modification is invalid. In the prior art, there have been some studies on modification of the negative electrode structure of sodium batteries. For example, the patent of the invention of publication No. CN120767309A discloses a strategy for constructing an artificial Solid Electrolyte Interface (SEI) on the surface of sodium, a layer of nickel selenide powder is coated on the surface of sodium metal by a rolling method, and nickel selenide spontaneously reacts to form sodium selenide and nickel (Na 2Se/Ni）.Na2 Se has excellent sodium philicity and can induce uniform deposition of sodium ions, metal Ni has higher mechanical strength, dendrite penetration artificial SEI is placed, the method suppresses dendrite problem to a certain extent, but the artificial SEI does not have sufficient sodium deposition space, the requirement of large sodium deposition amount cannot be met, and the patent of the invention of publication No. CN115295792A provides a composite metal sodium negative electrode material, adopts a porous organic film as a framework, deposits an alloy type conductive sodium philic layer (such as nickel phosphorus alloy) on the surface, and fills sodium metal by a melting or tabletting method. Therefore, although the prior art has made a certain progress in the structural design of the negative electrode of the sodium battery, an interface modification strategy which can effectively regulate and control the sodium deposition behavior and inhibit the dendrite growth and has the advantages of simple process and easy large-scale preparation is still lacking. Therefore, a novel three-dimensional interface interlayer is developed, and the interface sodium affinity characteristic is regulated while ensuring good ion transmission so as to realize bottom-up compact and uniform sodium deposition, and the novel three-dimensional interface interlayer has important significance for promoting the practical application of sodium metal batteries. Disclosure of Invention Aiming at the technical problems of undensified sodium deposition, volume expansion, dendrite generation, interface failure and the like caused by easy occurrence of a top deposition phenomenon of a 3D interface i