CN-117758118-B - Mg-In-Ca-Y alloy for anode material of magnesium air battery and preparation method thereof

Abstract

The invention relates to the field of chemical power electrode materials, and discloses a Mg-In-Ca-Y alloy of a magnesium air battery anode material and a preparation method thereof, wherein the Mg-In-Ca-Y alloy comprises, by mass, 97% of Mg, 2% of In, 0.5% of Ca and 0.5% of Y, and the Mg-In-Ca-Y alloy has a finely dispersed second phase, uniformly distributed twin crystals and cylindrically oriented grains. So as to develop the anode material of the magnesium air battery with high performance and solve the problem that the discharge performance of the existing magnesium air battery is not high enough.

Inventors

• WU LIANG
• HE YUANTAI
• WU TAO
• WU RONGQIAN
• YAO WENHUI
• YUAN YUAN
• HUANG GUANGSHENG
• WANG JINGFENG
• PAN FUSHENG

Assignees

• 重庆新型储能材料与装备研究院

Dates

Publication Date

20260505

Application Date

20231222

Claims (8)

1. 1. The Mg-In-Ca-Y alloy is characterized by comprising 97wt.% of Mg, 2wt.% of In, 0.5wt.% of Ca and 0.5wt.% of Y, and has a finely dispersed second phase, uniformly distributed twin crystals and cylindrically oriented grains.
2. 2. The Mg-In-Ca-Y alloy as set forth In claim 1, wherein the purity of Mg is greater than 99.9%, the purity of In is greater than 99.9%, the purity of Ca is greater than 99.9%, and the purity of Y is greater than 99.9%.
3. 3. The preparation method of the Mg-In-Ca-Y alloy of the anode material of the magnesium air battery is characterized by comprising the following steps: S1, smelting, namely sequentially melting magnesium blocks, pure In, mg-20Y intermediate alloy and Mg-30Ca intermediate alloy In a protective atmosphere to obtain alloy melt; Removing magnesium oxide on the surface of the alloy melt, and obtaining an alloy cast ingot through condensation treatment; S2, solid solution, namely placing the cast ingot at 400 ℃ for heat preservation for 24 hours; S3, hot extrusion, namely performing hot extrusion treatment on the alloy ingot; the extrusion temperature is 350 ℃, the extrusion ratio is 40:1, and the block with the thickness of 2mm is obtained, namely the Mg-In-Ca-Y alloy of the anode material of the magnesium air battery.
4. 4. The method for preparing a Mg-In-Ca-Y alloy as a magnesium air battery anode material according to claim 3, wherein In S1, the protective atmosphere is a mixed protective gas of CO 2 and SF 6 , and the volume ratio of CO 2 ：SF 6 is 35:1.
5. 5. The method for preparing the Mg-In-Ca-Y alloy as claimed In claim 4, wherein In S1, magnesium oxide on the surface of the alloy melt is removed by adding a refining agent into the alloy melt under a protective gas atmosphere until the surface of the alloy melt reaches a preset standard.
6. 6. The method for preparing the Mg-In-Ca-Y alloy as defined In claim 5, wherein the refining agent is a mixed solvent of MgCl 2 、KCl、BaCl 2 and CaF 2 , and the mass ratio of MgCl 2 ：KCl：BaCl：CaF 2 In the mixed solvent is 46:42:8:5.
7. 7. The method for preparing the Mg-In-Ca-Y alloy as claimed In claim 6, wherein In the step S3, before the hot extrusion treatment is carried out on the alloy ingot, the oxide on the surface of the alloy ingot is removed by polishing, and the polished alloy ingot is preheated for 30min under the environment of 350 ℃.
8. 8. A magnesium air battery is characterized by comprising the Mg-In-Ca-Y alloy prepared by the preparation method described In claim 7 as an anode material.

Description

Mg-In-Ca-Y alloy for anode material of magnesium air battery and preparation method thereof Technical Field The invention relates to the field of chemical power electrode materials, in particular to a Mg-In-Ca-Y alloy of a magnesium air battery anode material and a preparation method thereof. Background The magnesium air battery is a metal fuel battery, and the principle is that oxygen in the air is used as an anode active material, magnesium metal is used as a cathode active material, and oxygen in the air continuously reaches an electrochemical reaction interface through a gas diffusion electrode to react with the magnesium metal to release electric energy. As a novel clean, safe and efficient battery, the magnesium air battery has the advantages of abundant reserves, low price, simple processing technology and the like, and compared with other types of metal-air batteries (Al, li, na, fe, zn and the like), the magnesium air battery also has the advantages of negative standard electrode potential, large theoretical specific capacity, theoretical discharge voltage, good energy density synthesis and the like. However, the following problems in the practical use process of the magnesium air battery affect the popularization and application of the magnesium air battery, namely firstly, the discharge voltage is far lower than the theoretical voltage value of the magnesium air battery because the magnesium oxide as a discharge product is attached to the surface of the anode material, secondly, the utilization efficiency of the magnesium alloy anode material is greatly reduced due to self-corrosion of magnesium and magnesium alloy and the 'blocky effect' generated when part of the magnesium alloy is separated from a matrix in the discharge process, and finally, slow cathode dynamics is a main reason for restricting the development of the magnesium air battery. Disclosure of Invention The invention aims to provide a Mg-In-Ca-Y alloy of a magnesium air battery anode material and a preparation method thereof, so as to develop the magnesium air battery anode material with high performance and solve the problem that the discharge performance of the existing magnesium air battery is not high enough. The Mg-In-Ca-Y alloy for the anode material of the magnesium air battery comprises, by mass, 97% of Mg, 2% of In, 0.5% of Ca and 0.5% of Y, wherein the Mg-In-Ca-Y alloy has a finely dispersed second phase, uniformly distributed twin crystals and cylindrically oriented grains. Aiming at the problem of low discharge performance of the anode material of the magnesium air battery, the magnesium air battery anode material Mg-In-Ca-Y alloy with excellent discharge performance, which is prepared by taking high-purity Mg, in, ca, Y metal as a raw material through smelting, solution treatment and hot extrusion, has the excellent performance of 1.406V discharge voltage and 55.3% anode utilization rate under the current density of 10mA/cm 2, and solves the problem of insufficient discharge performance of the existing magnesium air battery. The method also has the following beneficial effects: 1. By adding trace Ca and Y elements on the basis of the Mg-In alloy, the discharge performance is improved and the material cost is further controlled. 2. The second phase Mg 2 Ca phase and Mg 24Y5 phase In the Mg-In-Ca-Y alloy are refined, dispersed and present a 'waterfall' shape, so that more evenly distributed twin crystals and crystal grains with cylindrical orientations exist In the alloy, and the alloy is favorable for exhibiting high discharge performance. 3. Because the potential of the Mg 2 Ca phase of the second phase In the Mg-In-Ca-Y alloy is about 50mV less than that of the magnesium matrix, a galvanic corrosion effect can be generated between the Mg 2 Ca phase and the magnesium matrix, and the Mg 2 Ca phase serving as an anode of galvanic corrosion can be dissolved before the magnesium matrix In the discharging process, so that the discharging performance of the magnesium alloy is further improved by reducing the adsorption force between a discharging product and the matrix and accelerating the falling of the discharging product. 4. Controlling the content of In element to be 2wt.% can reduce the dendrite spacing of the alloy, thereby further improving the electrochemical activity of the magnesium alloy. Preferably, the purity of Mg is greater than 99.9%, the purity of In is greater than 99.9%, the purity of Ca is greater than 99.9%, and the purity of Y is greater than 99.9%. Preferably, a preparation method of the Mg-In-Ca-Y alloy of the anode material of the magnesium air battery is also provided, which comprises the following steps: S1, smelting, namely sequentially melting magnesium blocks, pure In, mg-20Y intermediate alloy and Mg-30Ca intermediate alloy In a protective atmosphere to obtain an alloy melt, removing magnesium oxide on the surface of the alloy melt, and obtaining an alloy cast ingot through condensation treatme