CN-122000307-A - Method for depositing ZnTi alloy on surface of lithium metal battery negative electrode

Abstract

The invention relates to the field of battery materials, in particular to a method for depositing ZnTi alloy on the surface of a lithium metal battery cathode, which comprises the steps of 1) selecting a substrate suitable for the lithium metal cathode, cleaning and drying, 2) weighing Zn oxide powder and Ti oxide powder according to a proportion, uniformly mixing, melting by vacuum melting to obtain a mixed melt, 3) rapidly putting the substrate into the mixed melt by a manipulator, repeatedly dip-coating, forming a multilayer film on the surface of the substrate, taking out, naturally cooling, 4) reducing Zn and Ti oxides on the dip-coated substrate into Zn and Ti alloy, pickling, cleaning, heat treatment and cooling to normal temperature. According to the invention, a layer of uniform and compact film is formed on the surface of the lithium metal negative electrode after reduction by dip-coating the molten Zn oxide and Ti oxide mixed melt, so that the growth of lithium dendrite is effectively inhibited, the cycle life and the safety performance of the battery are improved, and the ZnTi alloy can also improve the coulomb efficiency and the charge-discharge performance of the lithium metal negative electrode.

Inventors

• ZHANG XIAOYU
• XU LINA
• JIANG FUYI
• DU WEI
• YUAN HUA
• WU HEZHEN
• HAN TAO
• HOU CHUANXIN
• LI YOUJIE
• HUANG ZHENGMIN

Assignees

• 烟台大学

Dates

Publication Date

20260508

Application Date

20241106

Claims (5)

1. 1. A method for depositing ZnTi alloy on the surface of a lithium metal battery cathode is characterized in that, The method comprises the following steps: 1) Substrate processing Selecting a substrate suitable for a lithium metal anode, cleaning and drying for later use; 2) Preparation of Zn and Ti-containing Mixed powder Weighing Zn oxide powder and Ti oxide powder according to a proportion, uniformly mixing, and then smelting and melting by adopting vacuum to obtain a mixed melt; 3) Substrate dip coating Rapidly putting the substrate in the step 1) into the mixed melt in the step 2) by using a mechanical arm, repeatedly dip-coating, forming a multilayer film on the surface of the substrate, taking out, and naturally cooling; 4) Reduction treatment And 3) reducing Zn oxide and Ti oxide on the substrate subjected to dip coating in the step 3) into Zn and Ti alloy, then placing the alloy into hydrochloric acid for pickling, performing heat treatment after cleaning, and cooling to normal temperature to obtain the lithium metal battery cathode with the ZnTi alloy deposited on the surface.
2. 2. The method of depositing a ZnTi alloy on a negative electrode surface of a lithium metal battery according to claim 1, wherein the substrate is a copper foil or a nickel foil.
3. 3. The method for depositing a ZnTi alloy on a negative electrode surface of a lithium metal battery according to claim 1, wherein the Zn oxide is ZnO and the Ti oxide is TiO 2 .
4. 4. The method for depositing ZnTi alloy on the surface of the negative electrode of the lithium metal battery according to claim 1, wherein the molar ratio of Zn to Ti is 1 (0.5-1.5).
5. 5. The method for depositing a ZnTi alloy on a negative electrode surface of a lithium metal battery according to claim 1, wherein the reduction method is one of a hydrogen reduction method and a metal substitution method.

Description

Method for depositing ZnTi alloy on surface of lithium metal battery negative electrode Technical Field The invention relates to the field of battery materials, in particular to a method for depositing ZnTi alloy on the surface of a negative electrode of a lithium metal battery. Background Lithium metal batteries are of great interest due to their high energy density and long cycle life. However, lithium dendrites are easily formed in the lithium metal negative electrode during charge and discharge, resulting in degradation of battery performance and even safety accidents. In addition, the unstable SEI film on the surface of the lithium metal negative electrode also affects the coulombic efficiency and cycle life of the battery. Therefore, how to effectively improve the performance of the lithium metal negative electrode becomes a key problem for restricting the commercial application of the lithium metal battery. Disclosure of Invention Aiming at the problem that the instability of the surface of a lithium metal negative electrode of the existing lithium metal battery affects the battery performance, the invention provides a method for depositing ZnTi alloy on the surface of the negative electrode of the lithium metal battery, which comprises the following steps: 1) Substrate processing Selecting a substrate suitable for a lithium metal anode, cleaning and drying for later use; 2) Preparation of Zn and Ti-containing Mixed powder Weighing Zn oxide powder and Ti oxide powder according to a proportion, uniformly mixing, and then smelting and melting by adopting vacuum to obtain a mixed melt; 3) Substrate dip coating Rapidly putting the substrate in the step 1) into the mixed melt in the step 2) by using a mechanical arm, repeatedly dip-coating, forming a multilayer film on the surface of the substrate, taking out, and naturally cooling; 4) Reduction treatment And 3) reducing Zn oxide and Ti oxide on the substrate subjected to dip coating in the step 3) into Zn and Ti alloy, then placing the alloy into hydrochloric acid for pickling, performing heat treatment after cleaning, and cooling to normal temperature to obtain the lithium metal battery cathode with the ZnTi alloy deposited on the surface. Specifically, the substrate is copper foil or nickel foil, zn oxide is ZnO, ti oxide is TiO 2, and the molar ratio of Zn to Ti is 1 (0.5-1.5). Specifically, the reduction method adopted by the invention is one of a hydrogen reduction method and a metal substitution method. The method has the advantages that a layer of uniform and compact ZnTi alloy film can be formed on the surface of the lithium metal negative electrode after reduction through dip-coating the molten Zn oxide and Ti oxide mixed melt, the growth of lithium dendrites is effectively inhibited, the cycle life and the safety performance of the battery are improved, the ZnTi alloy has good electrochemical performance, and the coulomb efficiency and the charge-discharge performance of the lithium metal negative electrode can be improved. Detailed Description The invention is described below in connection with examples which are given solely for the purpose of illustration and are not intended to limit the scope of the invention. Example 1 A method for depositing ZnTi alloy on the surface of the negative electrode of lithium metal battery includes such steps as choosing nickel foil as substrate, washing, drying, and pretreating; and (3) weighing ZnO and TiO 2 powder according to the mol ratio of Zn to Ti of 1:1, uniformly mixing, melting by adopting a vacuum melting method, controlling the pressure of a vacuum furnace to be 1Pa and the temperature to be 2100 ℃ to obtain a mixed melt, quickly placing a substrate into the mixed melt by using a manipulator, standing for 3 seconds, taking out, vertically hovering until no melt drops, placing the substrate into the mixed melt, repeatedly dip-coating for 4 times, taking out, naturally cooling, forming 4 layers of mixed oxide films on the surface of the substrate, slowly reducing the mixed oxide films in a hydrogen stream of 200 ℃ for 12 hours to form a ZnTi alloy film, carrying out heat treatment on a nickel foil, wherein the temperature is 200 ℃ and the time is 1 hour, and naturally cooling to obtain the zinc-titanium-zinc alloy. Example 2 A method for depositing ZnTi alloy on the surface of negative electrode of lithium metal battery includes such steps as choosing copper foil as substrate, washing, drying, proportionally mixing ZnO and TiO 2 powder, smelting by vacuum smelting method, controlling the pressure of vacuum furnace to be 1Pa and temp to 2100 deg.C, quickly putting substrate in mixed melt, holding for 5 seconds, immersing vertically until it is not dropped, immersing again for 2 times, natural cooling, forming 2 layers of mixed oxide film on the surface of substrate, putting substrate in Na metal melt at 500 deg.C for slow reduction for 24 hr under the protection of Ar gas, washing with diluted hydroc