Preparation method of ternary nanomaterial and its products and applications

Abstract

The present invention provides a method for preparing a ternary nanomaterial. A lithium source, nickel salt, cobalt salt, and manganese salt are mixed and ground to obtain A. A is transferred to a glass vial and added to another open vial containing 1 ml of distilled water. After reaction in an oven, the vial is removed, dried at the same temperature, and then reground to obtain B. B is calcined to obtain a ternary powder. The ternary powder is placed in a vacuum tube furnace, with a polycrystalline sapphire substrate positioned in the relatively low-temperature area downstream of the furnace. The furnace is heated, and the pressure is increased to 100 Torr within 1 minute and maintained for 0.5 to 1 hour. The system temperature is raised to a specified set point. Argon gas is passed through the system. After reaction, the system is cooled to room temperature to obtain the final product. The ternary nanomaterial prepared by combining wet solid phase and thermal evaporation methods exhibits a large specific surface area and improved electrochemical performance. The initial discharge capacity is 177 mAh / g, and after 50 cycles, the discharge capacity is 169 mAh / g, with a capacity retention rate of 95.5%.

Description

Technical Field

[0001] The present invention relates to a preparation method of a cathode material for a lithium-ion battery, and particularly to a preparation method of a ternary nanomaterial, its product and application. Background Art

[0002] With the rapid development of smaller, lighter and higher-performance electronic and communication devices, people have put forward increasingly high requirements for the battery performance, especially the specific energy, for providing power for these devices. However, it has been difficult to further improve the specific capacity of commercially available lithium-ion batteries and MH / Ni batteries at present. Therefore, it is urgent to develop batteries with higher specific energy. As a high specific energy chemical power source, lithium-ion secondary batteries have been widely used in the fields of mobile communication, laptop computers, video cameras, cameras, portable instruments and meters, etc., and have rapidly developed into one of the most important secondary batteries at present. Lithium-ion batteries, as the latest generation of green high-energy storage batteries, have developed rapidly in the early 1990s. Lithium-ion batteries are favored because of their advantages such as high voltage, high energy density, long cycle life, and little environmental pollution.

[0003] Due to the ternary material LiNi

[0008] Co x Mn y O2 (0 < x < 1, 0 < y < 1) has characteristics superior to those of lithium iron phosphate and lithium cobaltate, and different performance ternary electrode materials can be prepared by adjusting the ratios of nickel, cobalt and manganese. With the rise and development of new energy vehicles, ternary materials are a research hotspot. [[ID=***]]

[0004] The present invention provides a method for preparing a ternary LiNi 1-x-y Co x Mn y O2 (0 < x < 1, 0 < y < 1) nanomaterial. The present invention combines a wet solid phase method with a thermal evaporation method to prepare the ternary nanomaterial. The reaction of the wet solid phase method plays a key role and can ultimately control the size and morphology of the material, while the thermal evaporation method can change the specific surface area of the material by further evaporating and recrystallizing the generated material, and thus can improve the electrochemical performance of the material. Summary of the Invention

[0005] To overcome the deficiencies of the prior art, the purpose of the present invention is to provide a preparation method of a ternary nanomaterial.

[0006] Another purpose of the present invention is to provide a ternary nanomaterial product obtained by the above method.

[0007] Another purpose of the present invention is to provide an application of the above product.

[0008] The object of the present invention is achieved by the following scheme: A method for preparing a ternary nanomaterial, characterized in that the specific steps of the method are as follows:

[0009] (1) Mix a lithium source, a nickel salt, a cobalt salt, and a manganese salt in a molar ratio of 1:1 - x - y: x:y (0 < x < 1, 0 < y < 1)充分混合并在砂浆中研磨,得A;

[0010] (2) Transfer the obtained mixture to a 20 - milliliter glass vial, add another 3 - milliliter open vial containing 1 milliliter of distilled water. Then, keep the whole container in an oven at 70 - 80 °C. After reacting for 24 - 30 h, take out the water vial, dry it at the same temperature for 12 - 18 h and then re - grind to obtain B;

[0011] (3) Place B in a muffle furnace and heat it at a heating rate of 1 - 2 °C / min to 450 - 600 °C for calcination for 2 - 4 h to obtain a ternary powder material;

[0012] (4) Place the ternary powder material at the center of a vacuum (1 - 2 Torr) tube furnace. A polycrystalline sapphire substrate is placed in the relatively lower - temperature area (400 - 800 °C) downstream of the furnace. Heat the furnace chamber to 1350 - 1450 °C and keep it for 0.5 - 1 h. Then, increase the pressure to 100 Torr within 1 minute and continue for 0.5 - 1 h. The system temperature is increased to the specified set point at a rate of 10 °C - 15 °C / min. An argon carrier gas passes through the system at a rate of 20 - 25 sccm. After the reaction, cool the system to room temperature. It is found that a white product is deposited on the substrate to obtain the final product. -1 的速率升高到指定的设定点。氩气载气以20~25 sccm的速率通过系统,反应后,系统冷却到室温,发现白色产物沉积在衬底上,得最终产物。

[0013] Preferably, the lithium source is one or a combination of lithium hydroxide, lithium carbonate, and lithium acetate.

[0014] Preferably, the nickel salt is one or a combination of nickel acetate, nickel formate, and nickel citrate.

[0015] Preferably, the cobalt salt is one or a combination of cobalt acetate, cobalt formate, and cobalt citrate.

[0016] Preferably, the manganese salt is one or a combination of manganese acetate, manganese formate, and manganese citrate.

[0017] The present invention provides a ternary nanomaterial prepared by the method according to any one of the above.

[0018] The present invention provides an application of the ternary nanomaterial in a lithium - ion battery.

[0019] The present invention provides a ternary LiNi 1-x-y Co x Mn It should be noted that in the content of item [3], the Chinese part "充分混合并在砂浆中研磨,得A" is not complete in English translation. It should be something like "Mix them充分混合并在砂浆中研磨,得A", but the "充分混合并在砂浆中研磨" part is not well - formed in the original Chinese. You may need to check and correct the original Chinese content for a more accurate translation.y Method for preparing O2 (0 < x < 1, 0 < y < 1) nanomaterials. The present invention combines the wet solid phase method with the thermal evaporation method to prepare ternary nanomaterials. The reaction of the wet solid phase method plays a key role and can ultimately control the size and morphology of the materials. The thermal evaporation method can change the specific surface area of the materials by further evaporating and recrystallizing the generated materials, thereby improving the electrochemical performance of the materials. Brief Description of the Drawings

[0020] Figure 1 For Example 1 of ternary nanomaterials 1LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 Cycling life graph of O2. Detailed Implementation Modes

[0021] The present invention is described in detail through the following specific examples, but the protection scope of the present invention is not limited to these examples.

[0022] Example 1

[0023] A ternary nanomaterial, the ternary nanomaterial is LiNi 1-x-y Co x Mn y O2 (0 < x < 1, 0 < y < 1), and is prepared according to the following steps:

[0024] (1) Lithium acetate, nickel acetate, cobalt acetate and manganese acetate are fully mixed in a molar ratio of 0.01:0.0033:0.0033:0.0033 and ground in a mortar to obtain A;

[0025] (2) Transfer the obtained mixture to a 20 ml glass vial, add another 3 ml open vial containing 1 ml distilled water, then keep the whole container in an oven at 80 °C. After reacting for 24 h, take out the water vial, dry it at the same temperature for 12 h and then re-grind to obtain B;

[0026] (3) Place B in a muffle furnace and heat it to 450 °C at a heating rate of 2 °C / min and calcine for 4 h to obtain a ternary powder material;

[0027] (4) Place the ternary powder material at the center of a vacuum (1 - 2 Torr) tube furnace, place a polycrystalline sapphire substrate in the relatively lower temperature area (400 - 800 °C) downstream of the furnace. Heat the furnace chamber to 1350 °C and keep it for 1 h, then increase the pressure to 100 Torr within 1 minute and continue for 1 h; the system temperature is at 15 °C min -1The rate is increased to the specified set point, and argon carrier gas passes through the system at a rate of 25 sccm. After the reaction, the system is cooled to room temperature, and the resulting white product is deposited on the substrate, which is the final product ternary nanomaterial LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2.

[0028] Figure 1 To be ternary nanomaterial 1——LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2's cycle life graph. The initial discharge specific capacity is 177 mAh / g, and after 50 cycles, the discharge specific capacity is 169 mAh / g. Compared with the second discharge specific capacity, the capacity retention rate is 95.5%.

[0029] Example 2

[0030] A ternary nanomaterial, the ternary nanomaterial is LiNi 1-x-y Co x Mn y O2 (0 < x < 1, 0 < y < 1), and is prepared according to the following steps:

[0031] (1) Lithium hydroxide, nickel formate, cobalt formate and manganese formate are fully mixed in a molar ratio of 0.01:0.005 mol:0.0\03:0.002 and ground in a mortar to obtain A;

[0032] (2) Transfer the obtained mixture to a 20 - milliliter glass vial, and add another 3 - milliliter open vial containing 1 milliliter of distilled water. Then, the whole container is kept in an oven at 70 °C for 30 h. After taking out the water vial and drying at the same temperature for 18 h, it is re - ground to obtain B;

[0033] (3) Place B in a muffle furnace and heat it to 550 °C at a heating rate of 1 °C / min for calcination for 3 h to obtain a ternary powder material; <o000110>

[0034] (4) Place the ternary powder material at the center of a vacuum (2 Torr) tube furnace. A polycrystalline sapphire substrate is placed in the relatively lower - temperature area (400 - 800 °C) downstream of the furnace. Heat the furnace chamber to 1400 °C and keep it for 0.5 h, then increase the pressure to 100 Torr within 1 minute and continue for 1 h; The system temperature is increased to the specified set point at a rate of 15 °C / min -1 The rate is increased to the specified set point, and argon carrier gas passes through the system at a rate of 20 sccm. After the reaction, the system is cooled to room temperature, and the obtained white product is deposited on the substrate, which is the final product ternary nanomaterial LiNi 0.5 Co 0.3 Mn0.2 O2.

[0035] Example 3

[0036] A ternary nanomaterial, the ternary nanomaterial being LiNi 1-x-y Co x Mn y O2 (0 < x < 1, 0 < y < 1), which is prepared according to the following steps:

[0037] (1) Lithium carbonate, nickel citrate, cobalt citrate and manganese citrate are fully mixed in a molar ratio of 0.01 mol: 0.008 mol: 0.001 mol: 0.001 mol and ground in a mortar to obtain A;

[0038] (2) The obtained mixture is transferred to a 20 ml glass vial, into which another 3 ml open vial containing 1 ml distilled water is added. Then, the whole container is kept in an oven at 80 °C. After reacting for 24 h, the water vial is taken out, dried at the same temperature for 18 h and then re-ground to obtain B;

[0039] (3) B is placed in a muffle furnace and heated to 600 °C at a heating rate of 1 °C / min for calcination for 2 h to obtain a ternary powder material;

[0040] (4) The ternary powder material is placed at the center of a vacuum (1 Torr) tube furnace, and a polycrystalline sapphire substrate is placed in the relatively lower temperature region (400 - 800 °C) downstream of the furnace. The furnace chamber is heated to 1450 °C and kept for 0.5 h, then the pressure is increased to 100 Torr within 1 minute and kept for another 0.5 h; the system temperature is increased to the specified set point at a rate of 10 °C / min -1 and the argon carrier gas passes through the system at a rate of 2� sccm. After the reaction, the system is cooled to room temperature, and the obtained white product is deposited on the substrate, which is the final product ternary nanomaterial LiNi 0.8 Co 0.1 Mn 0.1 O2.

Claims

1. A method for preparing a ternary nanomaterial, wherein the ternary nanomaterial is LiNi 1-x-y Co x Mn y O2, where 0 < x < 1, 0 < y < 1, characterized in that it comprises the following preparation steps: (1) Mix a lithium source, a nickel salt, a cobalt salt, and a manganese salt in a molar ratio of 1:(1 - x - y):x:y, where 0 < x < 1 and 0 < y < 1, and grind them thoroughly in mortar to obtain A; (2) Transfer the obtained mixture to a 20 - milliliter glass vial, add another 3 - milliliter open vial containing 1 milliliter of distilled water, then keep the whole container in an oven at 70 - 80 °C. After reacting for 24 - 30 h, take out the vial with water, dry it at the same temperature for 12 - 18 h and then re - grind to obtain B; (3) Place B in a muffle furnace and heat it at a heating rate of 1 - 2 °C / min to 450 - 600 °C for calcination for 2 - 4 h to obtain the ternary powder material; (4) Place the ternary powder material in the center of a 1-2 Torr vacuum tube furnace, and place the polycrystalline sapphire substrate in the downstream relatively low temperature area of ​​400-800 °C. Heat the furnace to 1350-1450 °C and maintain it for 0.5-1 h. Then, increase the pressure to 100 Torr within 1 minute and continue for another 0.5-1 h. The system temperature is increased at a rate of 10 °C-15 °C min-1. -1 The rate is raised to the specified set point, and the argon carrier gas passes through the system at a rate of 20-25 sccm. After the reaction, the system is cooled to room temperature, and the resulting white product is deposited on the substrate, which is the final product, the ternary nanomaterial LiNi 1-x-y Co x Mn y O2.

2. The method for preparing a ternary nanomaterial according to claim 1, characterized in that: The lithium source is one or a combination of lithium hydroxide, lithium carbonate, and lithium acetate.

3. The method for preparing a ternary nanomaterial according to claim 1, characterized in that: The nickel salt is one or a combination of nickel acetate, nickel formate, and nickel citrate.

4. The method for preparing a ternary nanomaterial according to claim 1, characterized in that: The cobalt salt is one or a combination of cobalt acetate, cobalt formate, and cobalt citrate.

5. The method for preparing a ternary nanomaterial according to claim 1, characterized in that: The manganese salt is one or a combination of manganese acetate, manganese formate, and manganese citrate.

6. The method for preparing a ternary nanomaterial according to any one of claims 1 to 5, characterized in that: Prepared according to the following steps: (1) Mix lithium acetate, nickel acetate, cobalt acetate, and manganese acetate in a molar ratio of 0.01:0.0033:0.0033:0.0033 and grind them thoroughly in mortar to obtain A; (2) Transfer the obtained mixture to a 20 - milliliter glass vial, add another 3 - milliliter open vial containing 1 milliliter of distilled water, then keep the whole container in an oven at 80 °C. After reacting for 24 h, take out the vial with water, dry it at the same temperature for 12 h and then re - grind to obtain B; (3) Place B in a muffle furnace and heat it at a heating rate of 2 °C / min to 450 °C for calcination for 4 h to obtain the ternary powder material; (4) The ternary powder material is placed in the center of a 1-2 Torr vacuum tube furnace, and the polycrystalline sapphire substrate is placed in the downstream of the furnace at a relatively low temperature of 400-800 °C. The furnace is heated to 1350 °C and maintained for 1 h. The pressure is then increased to 100 Torr within 1 minute and maintained for another 1 h. The system temperature is increased at a rate of 15 °C min -1 The rate is raised to the specified set point, and the argon carrier gas is passed through the system at a rate of 25 sccm. After the reaction, the system is cooled to room temperature, and the resulting white product is deposited on the substrate, which is the final product, the ternary nanomaterial LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2.

7. The method for preparing a ternary nanomaterial according to any one of claims 1 to 5, characterized in that: Prepared according to the following steps: (1) Mix lithium hydroxide, nickel formate, cobalt formate, and manganese formate in a molar ratio of 0.01:0.005:0.003:0.002 and grind them thoroughly in mortar to obtain A; (2) Transfer the obtained mixture to a 20 - milliliter glass vial, add another 3 - milliliter open vial containing 1 milliliter of distilled water, then keep the whole container in an oven at 70 °C. After reacting for 30 h, take out the vial with water, dry it at the same temperature for 18 h and then re - grind to obtain B; (3) Place B in a muffle furnace and heat it at a heating rate of 1 °C / min to 550 °C for calcination for 3 h to obtain the ternary powder material; (4) The ternary powder material was placed in the center of a 2 Torr vacuum tube furnace, and the polycrystalline sapphire substrate was placed in the downstream relatively low temperature area of ​​400-800 °C. The furnace was heated to 1400 °C and maintained for 0.5 h. The pressure was then increased to 100 Torr within 1 min and continued for another 1 h. The system temperature was increased at 15 °C min -1 The rate is raised to the specified set point, and the argon carrier gas is passed through the system at a rate of 20 sccm. After the reaction, the system is cooled to room temperature, and the resulting white product is deposited on the substrate, which is the final product, the ternary nanomaterial LiNi 0.5 Co 0.3 Mn 0.2 O2.

8. The method for preparing a ternary nanomaterial according to any one of claims 1 to 5, characterized in that: Prepared according to the following steps: (1) Mix lithium carbonate, nickel citrate, cobalt citrate, and manganese citrate in a molar ratio of 0.01:0.008:0.001:0.001 and grind them thoroughly in mortar to obtain A; (2) Transfer the obtained mixture to a 20 - milliliter glass vial, add another 3 - milliliter open vial containing 1 milliliter of distilled water, then keep the whole container in an oven at 80 °C. After reacting for 24 h, take out the vial with water, dry it at the same temperature for 18 h and then re - grind to obtain B; (3) Place B in a muffle furnace and heat it to 600°C at a heating rate of 1°C / min and calcine it for 2 h to obtain a ternary powder material; (4) The ternary powder material was placed in the center of a 1 Torr vacuum tube furnace, and the polycrystalline sapphire substrate was placed in the downstream relatively low temperature area of ​​400-800 °C. The furnace was heated to 1450 °C and maintained for 0.5 h. The pressure was then increased to 100 Torr within 1 minute and continued for another 0.5 h. The system temperature was increased at 10 °C min -1 The rate is raised to the specified set point, and the argon carrier gas is passed through the system at a rate of 25 sccm. After the reaction, the system is cooled to room temperature, and the resulting white product is deposited on the substrate, which is the final product, the ternary nanomaterial LiNi 0.8 Co 0.1 Mn 0.1 O2.

9. A ternary nanomaterial, characterized in that Prepared according to any one of claims 1 to 8.

10. Use of the ternary nanomaterial according to claim 9 in a lithium-ion battery.

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