阅读说明：本技术 一种氟化碳修饰的三氟化铁正极材料的制备方法 (Preparation method of carbon fluoride modified ferric trifluoride cathode material ) 是由 王京亮 张红梅 朱艳丽 冉岭 李美玉 姚利 潘志鹏 刘方 吴启兵 于 2021-06-17 设计创作，主要内容包括：本方案公开了热电池材料技术领域的一种氟化碳修饰的三氟化铁正极材料的制备方法；包括(1)将碳纤维材料加入到分散剂中,搅拌均匀得到混合液；(2)将Fe粉加入到混合液中,搅拌均匀得到混合物溶液；(3)将混合物溶液加热至50℃～70℃,继续搅拌至得到膏状物；(4)对膏状物进行高能球磨,得到混合浆料；(5)将混合浆料在60～70℃的温度下烘干,然后冷却至常温,再对冷却后的混合酱料进行研磨,得到碳纤维包覆的Fe粉；(6)将碳纤维包覆的Fe粉进行氟化处理,经冷却、研磨,制得氟化碳修饰的三氟化铁正极材料。本申请FeF-3正极材料,可有效延长电池的工作时间,提高热电池单体电池的工作电压,进而提高热电池的比特性。(The scheme discloses a preparation method of a carbon fluoride modified ferric trifluoride anode material in the technical field of thermal battery materials; adding a carbon fiber material into a dispersing agent, and uniformly stirring to obtain a mixed solution; (2) adding Fe powder into the mixed solution, and uniformly stirring to obtain a mixture solution; (3) heating the mixture solution to 50-70 ℃, and continuously stirring to obtain a paste; (4) carrying out high-energy ball milling on the paste to obtain mixed slurry; (5) drying the mixed slurry at the temperature of 60-70 ℃, then cooling to normal temperature, and grinding the cooled mixed paste to obtain carbon fiber coated Fe powder; (6) and (3) carrying out fluorination treatment on the Fe powder coated by the carbon fibers, and cooling and grinding to obtain the ferric trifluoride anode material modified by the carbon fluoride. FeF of the present application 3 The anode material can effectively prolong the work of the batteryAnd time is saved, the working voltage of the single thermal battery is increased, and the specific characteristic of the thermal battery is further improved.)

1. A preparation method of a carbon fluoride modified ferric trifluoride anode material is characterized by comprising the following steps: the method comprises the following steps:

(1) adding a carbon fiber material into a dispersing agent, and then uniformly stirring to obtain a mixed solution;

(2) adding Fe powder into the mixed solution, and uniformly stirring to obtain a mixture solution;

(3) heating the mixture solution to 50-70 ℃, and continuously stirring to obtain a paste;

(4) placing the paste into a high-energy ball mill for high-energy ball milling at the rotating speed of more than 3000r/min for 30-2 min, stopping running, cooling for more than 10min, running the high-energy ball mill again, repeating the steps, wherein the total time of the high-energy ball milling reaches 1-2 h, and obtaining mixed slurry;

(5) drying the mixed slurry at the temperature of 60-70 ℃, then cooling to normal temperature, and grinding the cooled mixed paste to obtain carbon fiber coated Fe powder;

(6) putting the Fe powder coated with the carbon fibers into a tubular furnace for fluorination treatment, wherein the fluorination treatment temperature is 350-450 ℃, and the fluorination treatment time is 8-16 h; during the fluorination treatment, firstly filling nitrogen into the tubular furnace, and then continuously introducing fluorine gas into the tubular furnace until the fluorination treatment is finished; and cooling the Fe powder coated by the carbon fibers to normal temperature after the fluorination treatment is finished, and then grinding and sieving the Fe powder by a sieve of 100-200 meshes to prepare the carbon fluoride modified ferric trifluoride cathode material.

2. The method for preparing a carbon fluoride-modified ferric trifluoride positive electrode material according to claim 1, wherein: the weight ratio of the carbon fiber, the dispersing agent and the Fe powder is (0.1-0.9): 1-1.5): 1.

3. The method for preparing a carbon fluoride-modified ferric trifluoride positive electrode material according to claim 2, wherein: the weight ratio of the carbon fiber, the dispersing agent and the Fe powder is (0.3-0.7): 1.1-1.3): 1.

4. The method for preparing a carbon fluoride-modified ferric trifluoride positive electrode material according to claim 3, wherein: the dispersant is at least one of absolute ethyl alcohol and acetone.

5. The method for producing a carbon fluoride-modified ferric trifluoride positive electrode material according to any one of claims 1 to 4, wherein: the high-energy ball mill is a high-energy ball milling cup.

6. The method for preparing a carbon fluoride-modified ferric trifluoride positive electrode material according to claim 5, wherein: when high-energy ball milling is carried out, zirconia balls are added.

7. The method for preparing a carbon fluoride-modified ferric trifluoride positive electrode material according to claim 6, wherein: in the step (2), the added Fe powder is sieved by a sieve of 200-300 meshes.

8. The method for preparing a carbon fluoride-modified ferric trifluoride positive electrode material according to claim 7, wherein: in the step (4), the rotating speed of the high-energy ball mill is 3000-8000 r/min.

9. The method for preparing a carbon fluoride-modified ferric trifluoride positive electrode material according to claim 8, wherein: in the step (5), the drying time is 8-12 h.

Technical Field

The invention belongs to the technical field of thermal battery materials, and particularly relates to a preparation method of a carbon fluoride modified ferric trifluoride anode material.

Background

The thermal battery is a heat activated reserve battery, which is a disposable reserve battery activated by using molten salt as electrolyte and melting the molten salt by using a heat source, and the internal temperature is 450-550 ℃ when the thermal battery works. The thermal battery has small internal resistance, high specific energy and specific power, wide use environment temperature, long storage time, quick and reliable activation, compact structure, no directivity in use, no influence of installation direction, good mechanical property, no need of maintenance and the like, is popular in the military world once coming out, and is developed into an ideal power supply of modern weapons and emergency systems such as missiles, nuclear weapons, artillery, ejection chairs, black boxes and the like.

With the rapid development of weaponry, the weight reduction, miniaturization and high maneuverability are continuously enhanced, and a matched battery of the high maneuverability battery has better electrochemical performance, and particularly a matched power supply of a high maneuverability cruise missile and a high hypersonic cruise missile has the characteristics of high instantaneous pulse power and small volume and weight, namely the battery has the output characteristic of high specific power.

In order to meet the demand of model and promote the development of thermal battery technology, continuous exploration and research are also ongoing, and the anode material used in the lithium-based thermal battery at present is mainly sulfide (such as FeS)₂、CoS₂) The potential of the electrode of the sulfide anode is low, the internal resistance is high, and the monomer voltage is only 1.9-2.1V under the condition of matching with the lithium alloy, so that the application requirement of a high-specific-power thermal battery cannot be met. Under the condition that the NiCl2 positive electrode material is matched with the lithium alloy, the monomer voltage of 2.5-2.7V is obtained, and the specific power of the battery is improvedThe positive electrode material of (1). However, as the on-board battery power requirements become higher and higher, NiCl₂The anode material can not meet the use requirement, and the electrode potential ratio NiCl is urgently needed to be developed₂Higher positive electrode materials for thermal batteries. And FeF₃The (ferric trifluoride) is matched with a lithium alloy cathode, has higher monomer voltage which is more than 3.2V, and is an ideal material for improving the specific property of the thermal battery.

Currently, commercially available FeF₃The performance can not meet the requirements and can not be used. The preparation technology of the cathode material with the ultrahigh electrode potential is rarely reported.

Disclosure of Invention

The invention aims to provide a preparation method of a carbon fluoride modified ferric fluoride anode material, which prolongs the working time of a battery, improves the working voltage of a single battery of the thermal battery and further improves the specific characteristics of the thermal battery by preparing the carbon fluoride modified ferric fluoride anode material.

The preparation method of the carbon fluoride modified ferric trifluoride cathode material comprises the following steps:

(1) adding a carbon fiber material into a dispersing agent, and then uniformly stirring to obtain a mixed solution;

(2) adding Fe powder into the mixed solution, and uniformly stirring to obtain a mixture solution;

(3) heating the mixture solution to 50-70 ℃, and continuously stirring to obtain a paste;

(4) placing the paste into a high-energy ball mill for high-energy ball milling at the rotating speed of more than 3000r/min for 30-2 min, stopping running, cooling for more than 10min, running the high-energy ball mill again, repeating the steps, wherein the total time of the high-energy ball milling reaches 1-2 h, and obtaining mixed slurry;

(5) drying the mixed slurry at the temperature of 60-70 ℃, then cooling to normal temperature, and grinding the cooled mixed paste to obtain carbon fiber coated Fe powder;

(6) putting the Fe powder coated with the carbon fibers into a tubular furnace for fluorination treatment, wherein the fluorination treatment temperature is 350-450 ℃, and the fluorination treatment time is 8-16 h; during the fluorination treatment, firstly filling nitrogen into the tubular furnace, and then continuously introducing fluorine gas into the tubular furnace until the fluorination treatment is finished; and cooling the Fe powder coated by the carbon fibers to normal temperature after the fluorination treatment is finished, and then grinding and sieving the Fe powder by a sieve of 100-200 meshes to prepare the carbon fluoride modified ferric trifluoride cathode material.

The beneficial effect of this scheme:

(1) because the electrolyte used for the existing thermal battery is mainly eutectic salt containing halogen anions, the invention firstly carries out carbon fiber coating modification on Fe powder and then carries out fluorination treatment to prepare FeF modified by carbon fluoride₃Material, not only reducing FeF₃The material participates in the electrode reaction and the solubility of electrolyte, so that the retention time of an electrode interface double electric layer structure is prolonged, and the working time of the battery is finally prolonged. Secondly, the carbon fluoride is a hydrophobic material and is uniformly coated on the FeF₃The surface of the material solves Fe₃The material is easy to absorb moisture, so that FeF is obtained₃The working time of the anode material battery is increased from 200-300 s to 400-500 s, and the instantaneous specific power of the battery is increased from 11kW/kg to 14.5 kW/kg.

(2) Under the action of the dispersing agent, the two substances are mixed by adopting a high-energy ball milling mode, so that a good uniform mixing effect is achieved, and the problems of voltage hysteresis of the carbon fluoride anode material in the initial discharge stage and large heat generation under a large-current discharge condition are further solved.

Furthermore, the weight ratio of the carbon fiber, the dispersing agent and the Fe powder is (0.1-0.9): 1-1.5): 1. The proportion of the carbon fiber, the dispersing agent and the Fe powder is more balanced, and the prepared carbon fluoride modified ferric trifluoride anode material has better performance.

Furthermore, the weight ratio of the carbon fiber, the dispersing agent and the Fe powder is (0.3-0.7): 1.1-1.3): 1. The proportion of the carbon fiber, the dispersing agent and the Fe powder is more balanced, and the prepared carbon fluoride modified ferric trifluoride anode material has better performance.

Further, the dispersant is at least one of absolute ethyl alcohol and acetone. The absolute ethyl alcohol and the acetone are used as dispersing agents, and good effects can be achieved.

Further, the high-energy ball mill is a high-energy ball grinding cup. The high-energy ball milling cup has stable performance and better high-energy ball milling effect.

Furthermore, zirconia balls are added during high-energy ball milling. Zirconia balls are added in the process of high-energy ball milling, so that the uniformity of the mixed material is further improved.

Further, in the step (2), the added Fe powder is sieved by a 200-300-mesh sieve. The Fe powder sieved by the 200-300-mesh sieve has better mixing effect.

Further, in the step (4), the rotating speed of the high-energy ball mill is 3000-8000 r/min. The rotating speed within the range is beneficial to prolonging the service life of the high-energy ball mill while ensuring the ball milling effect.

Further, in the step (5), the drying time is 8-12 h. And drying for 8-12 h at the temperature of 60-70 ℃, so that the mixed slurry can be fully dried.

Detailed Description

The following is further detailed by way of specific embodiments:

example 1:

a preparation method of a carbon fluoride modified ferric trifluoride cathode material comprises the following steps:

(1) adding a carbon fiber material into absolute ethyl alcohol, and stirring for 1h to obtain a uniform mixed solution;

(2) adding the Fe powder which is sieved by a 200-mesh sieve into the mixed solution, and stirring for 1.5 hours to obtain a uniform mixture solution;

(3) heating the mixture solution to 50 ℃, and continuously stirring to obtain a paste;

(4) placing the paste into a high-energy ball mill for high-energy ball milling at the rotating speed of 3000r/min for 2min, then stopping running, cooling for 20min, running the high-energy ball mill again, and repeating the steps, wherein the total time of the high-energy ball milling reaches 2h to obtain mixed slurry; the high-energy ball mill adopts a high-energy ball milling cup, and zirconia balls are added during ball milling;

(5) drying the mixed slurry at 65 ℃ for 10h, then cooling to normal temperature, and grinding the cooled mixed paste to obtain carbon fiber coated Fe powder;

(6) putting the Fe powder coated with the carbon fibers into a tubular furnace for fluorination treatment, wherein the fluorination treatment temperature is 390 ℃, and the fluorination treatment time is 12 hours; during the fluorination treatment, firstly filling nitrogen into the tubular furnace, and then continuously introducing fluorine gas into the tubular furnace until the fluorination treatment is finished; and (3) cooling the Fe powder coated by the carbon fibers to normal temperature after the fluorination treatment is finished, and then grinding and sieving by a 200-mesh sieve to obtain the carbon fluoride modified ferric trifluoride anode material.

Wherein the weight ratio of the carbon fiber, the dispersing agent and the Fe powder is 0.1:1.5: 1.

Example 2:

a preparation method of a carbon fluoride modified ferric trifluoride cathode material comprises the following steps:

(1) adding a carbon fiber material into acetone, and stirring for 1.5h to obtain a uniform mixed solution;

(2) adding the Fe powder sieved by the 300-mesh sieve into the mixed solution, and stirring for 1h to obtain a uniform mixture solution;

(3) heating the mixture solution to 60 ℃, and continuously stirring to obtain a paste;

(4) placing the paste into a high-energy ball mill for high-energy ball milling at the rotating speed of 5000r/min for 1min, then stopping running, cooling for 15min, running the high-energy ball mill again, repeating the steps, and obtaining mixed slurry when the total time of the high-energy ball milling reaches 1.5 h; the high-energy ball mill adopts a high-energy ball milling cup, and zirconia balls are added during ball milling;

(5) drying the mixed slurry at the temperature of 60 ℃ for 12h, then cooling to normal temperature, and grinding the cooled mixed paste to obtain carbon fiber coated Fe powder;

(6) putting the Fe powder coated by the carbon fibers into a tubular furnace for fluorination treatment, wherein the fluorination treatment temperature is 350 ℃, and the fluorination treatment time is 16 h; during the fluorination treatment, firstly filling nitrogen into the tubular furnace, and then continuously introducing fluorine gas into the tubular furnace until the fluorination treatment is finished; and (3) cooling the Fe powder coated by the carbon fibers to normal temperature after the fluorination treatment is finished, and then grinding and sieving the Fe powder by a 100-mesh sieve to obtain the carbon fluoride modified ferric trifluoride cathode material.

Wherein the weight ratio of the carbon fiber, the dispersing agent and the Fe powder is 0.2:1.3: 1.

Example 3:

a preparation method of a carbon fluoride modified ferric trifluoride cathode material comprises the following steps:

(1) adding a carbon fiber material into a dispersing agent, and stirring for 2 hours to obtain a uniform mixed solution, wherein the dispersing agent comprises acetone and absolute ethyl alcohol, and the weight ratio of the acetone to the absolute ethyl alcohol is 1: 1;

(2) adding the Fe powder sieved by the 250-mesh sieve into the mixed solution, and stirring for 2 hours to obtain a uniform mixture solution;

(3) heating the mixture solution to 70 ℃, and continuously stirring to obtain a paste;

(4) placing the paste into a high-energy ball mill for high-energy ball milling at the rotating speed of 8000r/min for 30s, then stopping running, cooling for 15min, running the high-energy ball mill again, and repeating the steps, wherein the total time of the high-energy ball milling reaches 1h, so as to obtain mixed slurry; the high-energy ball mill adopts a high-energy ball milling cup, and zirconia balls are added during ball milling;

(5) drying the mixed slurry at the temperature of 70 ℃ for 8h, then cooling to normal temperature, and grinding the cooled mixed paste to obtain carbon fiber coated Fe powder;

(6) putting the Fe powder coated by the carbon fibers into a tubular furnace for fluorination treatment, wherein the fluorination treatment temperature is 450 ℃, and the fluorination treatment time is 8 hours; during the fluorination treatment, firstly filling nitrogen into the tubular furnace, and then continuously introducing fluorine gas into the tubular furnace until the fluorination treatment is finished; and (3) cooling the Fe powder coated by the carbon fibers to normal temperature after the fluorination treatment is finished, and then grinding and sieving the Fe powder by a 150-mesh sieve to obtain the carbon fluoride modified ferric trifluoride cathode material.

Wherein the weight ratio of the carbon fiber, the dispersing agent and the Fe powder is 0.3:1.5: 1.

FeF modified with fluorocarbon prepared in example 1₃The material was assembled as a positive electrode material (18.5 g), a separator (LiF-LiCl-NaF: MgO: 50, mass ratio) 8.6g, lithium boron (0.5 mm), and heating powderA single battery. Tests show that the single voltage of the thermal battery adopting the anode material is 3.29V, the working time of the thermal battery can reach 450s within 25V-33V of working voltage, and the instantaneous specific power of the thermal battery reaches 15.0 kW/kg.

FeF modified with fluorocarbon prepared in example 2₃The material was assembled as a positive electrode material (18.5 g), a separator (LiF-LiCl-NaF: MgO: 50, mass ratio) 8.6g, lithium boron (0.5 mm), and heating powderA single battery. Tests show that the single voltage of the thermal battery adopting the anode material is 3.29V, the working time of the thermal battery can reach 455s within 25V-33V of working voltage, and the instantaneous specific power of the thermal battery can reach 15.3 kW/kg.

FeF modified with fluorocarbon prepared in example 3₃The material was assembled as a positive electrode material (18.5 g), a separator (LiF-LiCl-NaF: MgO: 50, mass ratio) 8.6g, lithium boron (0.5 mm), and heating powderA single battery. Tests show that the single voltage of the thermal battery adopting the anode material is 3.29V, the working time of the thermal battery can reach 460s within 25V-33V of working voltage, and the instantaneous specific power of the thermal battery reaches 15.5 kW/kg.

The above description is only an example of the present invention and common general knowledge of known features in the schemes is not described herein. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.