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CN-117038835-B - Application of three-dimensional carbon fiber skeleton membrane modified by copper nano particles in water-based zinc metal battery

CN117038835BCN 117038835 BCN117038835 BCN 117038835BCN-117038835-B

Abstract

The invention discloses an application of a three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a water-based zinc metal battery, wherein the water-based zinc metal battery comprises a diaphragm and a zinc foil serving as an anode, the preparation method of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles comprises the steps of uniformly dripping a copper acetate solution onto horizontally-placed filter paper to enable the copper acetate solution to permeate into the filter paper from top to bottom, enabling copper acetate dissolved in the solution in the permeation process to be adsorbed by the filter paper, enabling the copper acetate content in the filter paper to be reduced in a gradient manner from top to bottom, drying the filter paper for gradient adsorption of the copper acetate, and then performing heat preservation and heat treatment in a hydrogen-argon mixed atmosphere at 300-400 ℃ to obtain the three-dimensional carbon fiber skeleton membrane modified by copper nano particles, wherein the three-dimensional carbon fiber skeleton membrane modified by copper nano particles serving as an auxiliary anode is placed between the zinc foil and the diaphragm, and one copper-rich side of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles is close to the zinc foil, and one copper-poor side of the three-dimensional carbon fiber skeleton membrane is close to the diaphragm.

Inventors

  • YAN WEIWEI

Assignees

  • 中国计量大学

Dates

Publication Date
20260508
Application Date
20230815

Claims (10)

  1. 1. The application of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a water-based zinc metal battery comprises a diaphragm and zinc foil serving as an anode, and is characterized in that a copper acetate solution is uniformly dripped on a flat filter paper, so that the copper acetate solution permeates into the filter paper from top to bottom, copper acetate dissolved in the solution in the permeation process is adsorbed by the filter paper, the copper acetate content in the filter paper is reduced in a gradient manner from top to bottom, the filter paper for gradient adsorption of copper acetate is dried and then subjected to heat preservation at 300-400 ℃ in a hydrogen-argon mixed atmosphere, and the three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a gradient manner is obtained; The three-dimensional carbon fiber skeleton membrane modified by the copper nano-particles in a gradient way is used as an auxiliary anode to be placed between the zinc foil and the diaphragm, and the copper-rich side of the three-dimensional carbon fiber skeleton membrane modified by the copper nano-particles in a gradient way is close to the zinc foil, and the copper-poor side of the three-dimensional carbon fiber skeleton membrane modified by the copper nano-particles is close to the diaphragm.
  2. 2. The use according to claim 1, wherein in the preparation of the three-dimensional carbon fiber skeleton membrane modified by copper nanoparticle gradient, the filter paper is made of cotton fiber.
  3. 3. The use according to claim 2, characterized in that after the heat-insulating treatment at 300-400 ℃, the surface layer of the cotton fiber is decomposed into carbon, the core of the fiber is also cotton.
  4. 4. The application of claim 1, wherein the particle size of the copper nanoparticles in the three-dimensional carbon fiber skeleton membrane modified by the copper nanoparticles in a gradient manner is 1-50 nm.
  5. 5. The application of claim 1, wherein in the preparation method of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a gradient manner, the concentration of the copper acetate solution is 1-40 g/L.
  6. 6. The application of claim 5, wherein in the preparation method of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a gradient way, the dosage of the copper acetate solution is calculated according to 0.3-0.4 mL/cm 2 filter paper.
  7. 7. The application of the three-dimensional carbon fiber skeleton membrane according to claim 6, wherein in the preparation method of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a gradient manner, the filter paper is soaked in the copper acetate solution for 5.5-6.5 hours.
  8. 8. The application of claim 1, wherein in the preparation method of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a gradient manner, the drying temperature is 55-65 ℃, and the drying time is 1.5-2.5 h.
  9. 9. The application of claim 1, wherein in the preparation method of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a gradient way, the heating rate of the heat treatment is 4-6 ℃ per minute.
  10. 10. The application of claim 1, wherein in the preparation method of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a gradient manner, the heat preservation time is 1.5-2.5 h at 300-400 ℃.

Description

Application of three-dimensional carbon fiber skeleton membrane modified by copper nano particles in water-based zinc metal battery Technical Field The invention relates to the technical field of water-based zinc metal batteries, in particular to application of a three-dimensional carbon fiber skeleton membrane modified by copper nano particles in a gradient manner in a water-based zinc metal battery. Background The metal zinc has the advantages of low electrode potential (0.76V compared with a standard hydrogen electrode), high theoretical capacity (820 mAh g -1 or 5855mAh cm -3), no toxicity, high abundance and the like, and is attractive as an ideal water-based battery cathode material. However, uncontrolled zinc deposition can lead to fatal zinc dendrite growth, thereby deteriorating cycle life. The low oxidation-reduction potential causes hydrogen evolution reaction of the zinc anode, increases the local pH value near the zinc anode, causes corrosion of metallic zinc, and causes formation of irreversible byproducts on the zinc anode. To facilitate commercial application of aqueous zinc metal batteries, there is an urgent need to achieve uniform, stable, reversible zinc deposition/stripping cycles for zinc anodes, resulting in long life, high rate zinc metal anodes. In order to overcome dendrite growth, hydrogen evolution and surface passivation problems of metallic zinc anodes, various strategies including interface engineering, electrolyte optimization, zinc anode structural design have been studied. The invention patent application with publication number of CN116364838A discloses a multifunctional ferroelectric polymer protective coating for a metal zinc anode, the invention patent application with publication number of CN115312704A discloses a metal zinc anode modified by a material containing rich oxygen sites, and the invention patent application with publication number of CN110148704A discloses a structural design of a network-shaped lightweight metal zinc electrode. At present, the metal zinc electrode can obtain better cycle stability under the conditions of low current density and low area capacity. However, at high current densities and high area capacities, the cycling performance of metallic zinc electrodes is still very poor. The main reason is that conventional zinc electrodes use 2D zinc sheets with very limited surface area. The deposition/stripping of zinc must be carried out concentrated on a limited surface of the zinc foil. Thus, high current densities necessarily result in high Zn 2+ flux and require rapid transfer/diffusion of Zn 2+. For an artificial or in-situ Solid Electrolyte Interface (SEI) film of a zinc anode, its low ionic conductivity and low Zn 2+ transfer number are difficult to meet the transport requirements of high flux Zn 2+. The 3D zinc anode may partially realize this prospect but is not the most perfect solution. The three-dimensional structure can increase the surface area of the zinc anode and reduce the deposition overpotential of zinc. However, the conventional three-dimensional zinc anode faces an unavoidable problem in that zinc is mainly deposited on the upper surface of the three-dimensional zinc anode. This phenomenon is particularly severe at high current densities, resulting in rapid dendrite growth. In addition, 3D pure zinc anodes are prone to collapse at high currents and capacities. And the 3D zinc anode loses the advantages of low cost and easy processing of the 2D zinc foil. For 3D non-zinc anodes, the amount of galvanization is very limited, typically less than 10mAh cm -2, not sufficient to perform a high capacity charge-discharge reaction. Disclosure of Invention The invention provides an application of a three-dimensional carbon fiber skeleton membrane (which can be simply called as three-dimensional carbon fiber skeleton membrane@copper) modified by copper nano particles in a water system zinc metal battery, wherein the three-dimensional carbon fiber skeleton membrane@copper has a simple and mild synthesis process and a unique structure, and can be used as an auxiliary anode to obviously improve the cycle performance of a metal zinc anode. The preparation method of the three-dimensional carbon fiber skeleton membrane modified by copper nano particles comprises the steps of uniformly dripping a copper acetate solution onto horizontally-placed filter paper to enable the copper acetate solution to permeate into the filter paper from top to bottom, absorbing copper acetate dissolved in the solution by the filter paper in the permeation process, and reducing the copper acetate content in the filter paper from top to bottom in a gradient manner, drying the filter paper for gradient absorption of the copper acetate, and then carrying out heat preservation and heat treatment at 300-400 ℃ in a hydrogen-argon mixed atmosphere to obtain the three-dimensional carbon fiber skeleton membrane modified by copper nano particles; The three-dimensional carbon