High-performance natural graphite-MnO composite electrode material and preparation method thereof

Abstract

The invention relates to a high-performance natural graphite-MnO composite electrode material and a preparation method of the high-performance natural graphite-MnO composite electrode material. The preparation method comprises the following steps that: a mixture of MnO2 and natural graphite is generated by virtue of reaction between KMnO4 solution and the natural graphite, wherein one part of the generated MnO2 goes into the natural graphite to form an intercalated structure, while the other part of the MnO2 is deposited on the surface of the natural graphite; next, the mixture is calcined in an inert atmosphere, and the MnO2 is reduced into MnO by utilizing the reducing property of the natural graphite, and therefore, the natural graphite-MnO composite material is formed. In the preparation method, the natural graphite is used as either a main body material or a reducing agent, the process is simplified, and the obtained composite material is excellent in properties. The natural graphite layers do not collapse as being supported by MnO among the natural graphite layers, the interlayer spacing of the natural graphite is expanded, so that lithium ions can be deintercalated quickly without affecting the structure of the natural graphite, and therefore, the cycle performance of the natural graphite composite electrode material can be improved favorably; the MnO deposited on the surface of the natural graphite is helpful to capacity improvement. The natural graphite composite electrode material with high capacity and good cycle performance can be obtained by combining the natural graphite and MnO.

Description

technical field

[0001] The invention relates to the technical field of preparation of lithium-ion battery electrode materials, in particular to a preparation method of a composite high-performance electrode material of natural graphite and MnO. Background technique

[0002] Lithium-ion secondary battery has the characteristics of high voltage, high volume specific capacity and mass specific capacity, green and environmental protection, and is of great significance to the sustainable development of energy. It is a new type of high energy density secondary battery. Smart grid has a wide range of applications. But with the rapid development of electric vehicles and other electronic devices, the demand for high-performance lithium-ion batteries is more urgent. Due to safety and cycle stability issues, the development of anode materials in Li-ion batteries has gone through a long period of development. At present, the commercial lithium-ion battery anode materials are mainly na...

Examples

Embodiment 1

[0028] A preparation method of natural graphite and MnO composite negative electrode material:

[0029] Spheroidize natural flake graphite to average particle size D 50 = 17 μm, adding natural flake graphite to KMnO 4 In the aqueous solution (5g / L), stir into a uniform dispersion, natural flake graphite and KMnO 4 The mass percentage of 85wt%: 15wt%. Add the dispersion liquid into a stainless steel reaction kettle and seal it, heat it to 160°C, keep it warm for 10 hours, cool it to room temperature, filter it with suction, and wash it with deionized water until it is colorless. The obtained product was vacuum-dried at 50°C for 5 hours (vacuum degree -0.1MPa), and then heat-treated at 500°C for 10 hours under an argon atmosphere to obtain a composite material of natural graphite and MnO. The obtained composite material was milled in a ball mill for 4 hours, the frequency of the ball mill was 45 Hz, and after passing through a 200-mesh sieve, the composite high-performance e...

Embodiment 2

[0031] Spheroidize natural flake graphite to average particle size D 50 = 17 μm, adding natural flake graphite to KMnO 4 In the aqueous solution (5g / L), stir into a uniform dispersion, natural flake graphite and KMnO 4 The mass percentage of 85wt%: 15wt%. Add the dispersion liquid into a stainless steel reaction kettle and seal it, heat it to 160°C, keep it warm for 10 hours, cool it to room temperature, filter it with suction, and wash it with deionized water until it is colorless. The obtained product was vacuum-dried at 50°C for 5 hours (vacuum degree -0.1MPa), and then heat-treated at 600°C for 10 hours under an argon atmosphere to obtain a composite material of natural graphite and MnO. The obtained composite material was milled in a ball mill for 4 hours, the frequency of the ball mill was 45 Hz, and after passing through a 200-mesh sieve, the composite high-performance electrode material of natural graphite and MnO was obtained.

Embodiment 3

[0033] Spheroidize natural flake graphite to average particle size D 50 = 17 μm, adding natural flake graphite to KMnO 4 In the aqueous solution (5g / L), stir into a uniform dispersion, natural flake graphite and KMnO 4 The mass percentage of 85wt%: 15wt%. Add the dispersion liquid into a stainless steel reaction kettle and seal it, heat it to 160°C, keep it warm for 10 hours, cool it to room temperature, filter it with suction, and wash it with deionized water until it is colorless. The obtained product was vacuum-dried at 50°C for 5 hours (vacuum degree -0.1MPa), and then heat-treated at 700°C for 10 hours under an argon atmosphere to obtain a natural graphite and MnO composite material. The obtained composite material was milled in a ball mill for 4 hours, the frequency of the ball mill was 45 Hz, and after passing through a 200-mesh sieve, the composite high-performance electrode material of natural graphite and MnO was obtained.

technical field

[0001] The invention relates to the technical field of preparation of lithium-ion battery electrode materials, in particular to a preparation method of a composite high-performance electrode material of natural graphite and MnO. Background technique

[0002] Lithium-ion secondary battery has the characteristics of high voltage, high volume specific capacity and mass specific capacity, green and environmental protection, and is of great significance to the sustainable development of energy. It is a new type of high energy density secondary battery. Smart grid has a wide range of applications. But with the rapid development of electric vehicles and other electronic devices, the demand for high-performance lithium-ion batteries is more urgent. Due to safety and cycle stability issues, the development of anode materials in Li-ion batteries has gone through a long period of development. At present, the commercial lithium-ion battery anode materials are mainly na...

Examples

Embodiment 1

[0028] A preparation method of natural graphite and MnO composite negative electrode material:

[0029] Spheroidize natural flake graphite to average particle size D 50 = 17 μm, adding natural flake graphite to KMnO 4 In the aqueous solution (5g / L), stir into a uniform dispersion, natural flake graphite and KMnO 4 The mass percentage of 85wt%: 15wt%. Add the dispersion liquid into a stainless steel reaction kettle and seal it, heat it to 160°C, keep it warm for 10 hours, cool it to room temperature, filter it with suction, and wash it with deionized water until it is colorless. The obtained product was vacuum-dried at 50°C for 5 hours (vacuum degree -0.1MPa), and then heat-treated at 500°C for 10 hours under an argon atmosphere to obtain a composite material of natural graphite and MnO. The obtained composite material was milled in a ball mill for 4 hours, the frequency of the ball mill was 45 Hz, and after passing through a 200-mesh sieve, the composite high-performance e...

Embodiment 2

[0031] Spheroidize natural flake graphite to average particle size D 50 = 17 μm, adding natural flake graphite to KMnO 4 In the aqueous solution (5g / L), stir into a uniform dispersion, natural flake graphite and KMnO 4 The mass percentage of 85wt%: 15wt%. Add the dispersion liquid into a stainless steel reaction kettle and seal it, heat it to 160°C, keep it warm for 10 hours, cool it to room temperature, filter it with suction, and wash it with deionized water until it is colorless. The obtained product was vacuum-dried at 50°C for 5 hours (vacuum degree -0.1MPa), and then heat-treated at 600°C for 10 hours under an argon atmosphere to obtain a composite material of natural graphite and MnO. The obtained composite material was milled in a ball mill for 4 hours, the frequency of the ball mill was 45 Hz, and after passing through a 200-mesh sieve, the composite high-performance electrode material of natural graphite and MnO was obtained.

Embodiment 3

[0033] Spheroidize natural flake graphite to average particle size D 50 = 17 μm, adding natural flake graphite to KMnO 4 In the aqueous solution (5g / L), stir into a uniform dispersion, natural flake graphite and KMnO 4 The mass percentage of 85wt%: 15wt%. Add the dispersion liquid into a stainless steel reaction kettle and seal it, heat it to 160°C, keep it warm for 10 hours, cool it to room temperature, filter it with suction, and wash it with deionized water until it is colorless. The obtained product was vacuum-dried at 50°C for 5 hours (vacuum degree -0.1MPa), and then heat-treated at 700°C for 10 hours under an argon atmosphere to obtain a natural graphite and MnO composite material. The obtained composite material was milled in a ball mill for 4 hours, the frequency of the ball mill was 45 Hz, and after passing through a 200-mesh sieve, the composite high-performance electrode material of natural graphite and MnO was obtained.

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