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CN-120998925-B - Fiber electrode and preparation method thereof

CN120998925BCN 120998925 BCN120998925 BCN 120998925BCN-120998925-B

Abstract

The invention relates to the technical field of carbon-based negative electrode materials for lithium ion batteries, in particular to a carbon-based fiber electrode and a preparation method thereof, ir is doped on the surface of the graphite felt fiber material by ion implantation, and the metal Ir can be used as a catalyst for preparing the carbon nano tube by a subsequent ALD method while improving the electrochemical activity of the carbon-based electrode. Studies have shown that a proper amount of metallic Ir can improve the low-temperature capacity achievement rate of a battery when the fibrous electrode is used as a negative electrode, but too much Ir can have a negative effect, so that the ion implantation amount of metallic Ir needs to be controlled to be 1.2×10 4 ions/cm 2 -7.2×10 8 ions/cm 2 . In addition, when Ir and Ru are compositely injected, a more excellent test effect can be obtained, the low-temperature battery capacity achievement rate exceeds 95%, and the method is suitable for the battery use requirements of new energy automobiles.

Inventors

  • YU SIJIA
  • TANG QIN
  • LIU TING

Assignees

  • 中南大学湘雅医院

Dates

Publication Date
20260505
Application Date
20250901

Claims (7)

  1. 1. The preparation method of the carbon-based fiber electrode is characterized by comprising the following steps of: pre-treating, namely soaking the graphite felt fiber material in absolute ethyl alcohol for 12-15 hours to obtain a deoiled graphite felt fiber material, then carrying out ultrasonic cleaning for a plurality of times by using deionized water until no ethanol residue exists, and standing and air-drying the graphite felt fiber material to obtain a pretreated graphite felt fiber material; The ion implantation Ir is that the pretreated graphite felt fiber material is put into metal steam vacuum arc power ion implantation equipment, metal Ir is selected for ion implantation, the ion voltage is 60-75keV, and the ion implantation amount of Ir metal is 1.2 multiplied by 10 4 ions/cm 2 -7.2×10 8 ions/cm 2 ; The ALD method for preparing the carbon nano tube comprises the steps of placing graphite felt fiber materials into atomic layer deposition equipment, introducing ethylene, and enabling carbon atoms in the ethylene to spontaneously accumulate on the surface of metal Ir through plasma discharge to form a carbon nano tube structure, wherein the plasma discharge power is 55-60W, the discharge time of a single cycle is 1.5-2.0s, the flow rate of the ethylene is 75-90sccm, each cycle comprises the step of purging residual gas in the atomic layer deposition equipment with inert gas, and finally, the carbon-based fiber electrode containing Ir and the carbon nano tube is obtained.
  2. 2. The method of claim 1, wherein the soaking time is 12 hours.
  3. 3. The method of claim 1, wherein the ion voltage is 60keV.
  4. 4. The method of claim 1, wherein the plasma discharge power is 55W.
  5. 5. The method of claim 1, wherein the ethylene has a flow rate of 75sccm.
  6. 6. The method of claim 1, wherein the single cycle has a discharge time of 1.5s.
  7. 7. A carbon-based fiber electrode, characterized in that it is produced by the method of any one of claims 1 to 6.

Description

Fiber electrode and preparation method thereof Technical Field The invention relates to the field of carbon-based negative electrode materials (H01M 4/1393) for lithium ion batteries, in particular to a carbon-based fiber electrode and a preparation method thereof. Background New energy automobiles are one of the most popular topics in the automobile industry today, and represent a future trend of the traffic field towards cleaner and more sustainable directions. As one of the important components of new energy automobiles, the activity degradation of lithium batteries in low-temperature environments is a key technical challenge, which directly affects the winter endurance and charging performance of electric automobiles. Based on this, the present invention is expected to improve the low-temperature activity of lithium batteries from electrode materials, and further improve the battery capacity achievement rate under low-temperature conditions. Disclosure of Invention The invention aims to provide a preparation method of a carbon-based fiber electrode, which can obtain the carbon-based fiber electrode with excellent low-temperature activity. The technical scheme of the invention is as follows: A method for preparing a carbon-based fiber electrode, comprising the steps of: pre-treating, namely soaking the graphite felt fiber material in absolute ethyl alcohol for 12-15 hours to obtain a deoiled graphite felt fiber material, then carrying out ultrasonic cleaning for a plurality of times by using deionized water until no ethanol residue exists, and standing and air-drying the graphite felt fiber material to obtain a pretreated graphite felt fiber material; The ion implantation Ir is that the pretreated graphite felt fiber material is put into metal steam vacuum arc power ion implantation equipment, metal Ir is selected for ion implantation, the ion voltage is 60-75keV, and the ion implantation amount of Ir metal is 1.2 multiplied by 10 4ions/cm2-7.2×108ions/cm2; The ALD method for preparing the carbon nano tube comprises the steps of placing graphite felt fiber materials into atomic layer deposition equipment, introducing ethylene, and enabling carbon atoms in the ethylene to spontaneously accumulate on the surface of metal Ir through plasma discharge to form a carbon nano tube structure, wherein the plasma discharge power is 55-60W, the discharge time of a single cycle is 1.5-2.0s, the flow rate of the ethylene is 75-90sccm, each cycle comprises the step of purging residual gas in the atomic layer deposition equipment with inert gas, and finally, the carbon-based fiber electrode containing Ir and the carbon nano tube is obtained. Preferably, the soaking time is 12 hours. Preferably, the ion voltage is 60keV. Preferably, the plasma discharge power is 55W. Preferably, the ethylene flow rate is 75sccm. Preferably, the discharge time of the single cycle is 1.5s. Preferably, in the ion implantation step, 1.2X10 6ions/cm2-7.2×108ions/cm2 of metal Ru is also implanted. Further, the invention also provides a carbon-based fiber electrode, which is prepared by the method. According to the invention, ir is doped on the surface of the graphite felt fiber material by ion implantation, and the metal Ir can be used as a catalyst for preparing the carbon nano tube by a subsequent ALD method while improving the electrochemical activity of the carbon-based electrode. Studies have shown that a proper amount of metallic Ir can improve the low-temperature capacity achievement rate of a battery when the fibrous electrode is used as a negative electrode, but too much Ir can have a negative effect, so that the ion implantation amount of metallic Ir needs to be controlled to be 1.2×10 4ions/cm2-7.2×108ions/cm2. In addition, when Ir and Ru are compositely injected, a more excellent test effect can be obtained, the low-temperature battery capacity achievement rate exceeds 95%, and the method is suitable for the battery use requirements of new energy automobiles. Detailed Description The technical effects of the present invention are verified by the following specific examples, but the embodiments of the present invention are not limited thereto. Example 1 Pre-treating, namely soaking the graphite felt fiber material in absolute ethyl alcohol for 12 hours to obtain a deoiled graphite felt fiber material, then carrying out ultrasonic cleaning for a plurality of times by using deionized water until no ethanol residue exists, and standing and air-drying the graphite felt fiber material to obtain a pretreated graphite felt fiber material; The ion implantation Ir is that the pretreated graphite felt fiber material is put into metal steam vacuum arc power ion implantation equipment, metal Ir is selected for ion implantation, the ion voltage is 60keV, and the ion implantation amount of Ir metal is 1.2 multiplied by 10 4ions/cm2; And preparing the carbon nano tube by ALD method, namely placing graphite felt fiber material into atomic layer dep