Composite conductive agent and preparation method thereof, electrode plate and lithium ion battery

Abstract

The invention relates to a composite conductive agent and a preparation method thereof, an electrode plate and a lithium ion battery, and belongs to the preparation field of a lithium ion battery material. The preparation method comprises the following steps of performing mixing on a mixed solution A of a catalyst and citric acid, and carbon black, and next, performing soaking on the mixture at 25-200 DEG C at 1-10MPa for 2-48h to obtain a material B; performing heating on the material B to 600-1,200 DEG C and then performing thermal insulation at 600-1,200 DEG C for 2h, and pumping hydrogen for 10-350min, and then performing thermal insulation at 600-1,200 DEG C for 2h, and pumping a carbon source mixed gas for 10-300min, and performing cooling to obtain a composite material C; and enabling the composite material C and a graphene oxide solution to be reacted at a temperature of 150-200 DEG C for 1-12h, and performing drying, and next, performing carbonization at a temperature of 800-900 DEG C for 2-6h, and performing cooling. The obtained composite conductive agent is high in tap density and conductive performance and has high application prospect in the field of the lithium battery.

Description

technical field

[0001] The invention relates to a composite conductive agent, a preparation method thereof, a pole piece and a lithium ion battery, and belongs to the field of preparation of lithium ion battery materials. Background technique

[0002] With the rapid development of electric vehicles, lithium-ion batteries are required to have higher energy density and fast charging performance. At present, the positive and negative materials used in lithium-ion batteries are lithium iron phosphate, ternary composite materials, lithium manganate, graphite and other materials, which have defects such as poor conductivity, and need to add conductive agents to improve the conductivity of the material. At present, from the market point of view, conductive agents mainly include conductive carbon black SP, conductive graphite (KS-6), vapor grown carbon fiber (VGCF), carbon nanotube (CNT), graphene, etc. However, the tap density of the above-mentioned conductive agent is low, thereb...

Examples

Embodiment 1

[0048] The preparation method of the composite conductive agent of the present embodiment comprises the following steps:

[0049] 1) Catalyst load:

[0050]The carbon black with a particle size of 200nm was washed with deionized water, dried, and then washed 50 times with 0.1mol / L hydrochloric acid solution, and then washed 50 times with 0.1mol / L sodium hydroxide solution. After drying, the pretreated Carbon black of 100nm nickel catalyst and 96g citric acid were added to 1000mL of deionized water to prepare mixed solution A, and then 100g of pretreated carbon black was added to 2000mL mixed solution A. And soak for 24 hours at 80°C and 5MPa under high pressure to obtain material B;

[0051] 2) Preparation of carbon black / carbon nanotubes:

[0052] Put material B into a quartz boat and put it in the middle of the tube furnace, raise the temperature to 800°C under the protection of inert gas, keep it warm for 2 hours, then change it to hydrogen for 180 minutes, then keep it a...

Embodiment 2

[0058] The preparation method of the composite conductive agent of the present embodiment comprises the following steps:

[0059] 1) Catalyst load:

[0060] Wash the carbon black with a particle size of 100nm with deionized water and dry it with 0.1mol / L hydrochloric acid solution for 50 times, then wash it with 0.1mol / L sodium hydroxide solution for 50 times, and dry it to obtain the pretreated carbon black; after that, 5.9g of ferric nitrate catalyst with a particle size of 10nm and 19.2g of citric acid were added to 200mL of deionized water to prepare mixed solution A, and then 100g of pretreated carbon black was added to 200mL of mixed solution A , and soaked at 25°C and 10MPa high pressure for 48h to obtain material B;

[0061] 2) Preparation of carbon black / carbon nanotubes:

[0062] Put material B into a quartz boat and put it in the middle of the tube furnace, raise the temperature to 600°C under the protection of inert gas, keep it warm for 2 hours, then change it t...

Embodiment 3

[0068] The preparation method of the composite conductive agent of the present embodiment comprises the following steps:

[0069] 1) Catalyst load:

[0070] Carbon black with a particle size of 200nm was washed with deionized water, dried, and then washed 100 times with 0.1mol / L hydrochloric acid solution, then washed 100 times with 0.1mol / L sodium hydroxide solution, and dried to obtain the pretreated The carbon black of 200nm cobalt catalyst and 192g citric acid were added to 2000mL of deionized water to prepare mixed solution A, and then 100g of pretreated carbon black was added to 200mL mixed solution A. And soak for 48 hours at 200°C and 1MPa high pressure to obtain material B;

[0071] 2) Preparation of carbon black / carbon nanotubes:

[0072] Put material B into a quartz boat and place it in the middle of the tube furnace, raise the temperature to 800°C under the protection of inert gas, keep it warm for 2 hours, then change it to hydrogen for 350 minutes, then keep it...

technical field

[0001] The invention relates to a composite conductive agent, a preparation method thereof, a pole piece and a lithium ion battery, and belongs to the field of preparation of lithium ion battery materials. Background technique

[0002] With the rapid development of electric vehicles, lithium-ion batteries are required to have higher energy density and fast charging performance. At present, the positive and negative materials used in lithium-ion batteries are lithium iron phosphate, ternary composite materials, lithium manganate, graphite and other materials, which have defects such as poor conductivity, and need to add conductive agents to improve the conductivity of the material. At present, from the market point of view, conductive agents mainly include conductive carbon black SP, conductive graphite (KS-6), vapor grown carbon fiber (VGCF), carbon nanotube (CNT), graphene, etc. However, the tap density of the above-mentioned conductive agent is low, thereb...

Examples

Embodiment 1

[0048] The preparation method of the composite conductive agent of the present embodiment comprises the following steps:

[0049] 1) Catalyst load:

[0050]The carbon black with a particle size of 200nm was washed with deionized water, dried, and then washed 50 times with 0.1mol / L hydrochloric acid solution, and then washed 50 times with 0.1mol / L sodium hydroxide solution. After drying, the pretreated Carbon black of 100nm nickel catalyst and 96g citric acid were added to 1000mL of deionized water to prepare mixed solution A, and then 100g of pretreated carbon black was added to 2000mL mixed solution A. And soak for 24 hours at 80°C and 5MPa under high pressure to obtain material B;

[0051] 2) Preparation of carbon black / carbon nanotubes:

[0052] Put material B into a quartz boat and put it in the middle of the tube furnace, raise the temperature to 800°C under the protection of inert gas, keep it warm for 2 hours, then change it to hydrogen for 180 minutes, then keep it a...

Embodiment 2

[0058] The preparation method of the composite conductive agent of the present embodiment comprises the following steps:

[0059] 1) Catalyst load:

[0060] Wash the carbon black with a particle size of 100nm with deionized water and dry it with 0.1mol / L hydrochloric acid solution for 50 times, then wash it with 0.1mol / L sodium hydroxide solution for 50 times, and dry it to obtain the pretreated carbon black; after that, 5.9g of ferric nitrate catalyst with a particle size of 10nm and 19.2g of citric acid were added to 200mL of deionized water to prepare mixed solution A, and then 100g of pretreated carbon black was added to 200mL of mixed solution A , and soaked at 25°C and 10MPa high pressure for 48h to obtain material B;

[0061] 2) Preparation of carbon black / carbon nanotubes:

[0062] Put material B into a quartz boat and put it in the middle of the tube furnace, raise the temperature to 600°C under the protection of inert gas, keep it warm for 2 hours, then change it t...

Embodiment 3

[0068] The preparation method of the composite conductive agent of the present embodiment comprises the following steps:

[0069] 1) Catalyst load:

[0070] Carbon black with a particle size of 200nm was washed with deionized water, dried, and then washed 100 times with 0.1mol / L hydrochloric acid solution, then washed 100 times with 0.1mol / L sodium hydroxide solution, and dried to obtain the pretreated The carbon black of 200nm cobalt catalyst and 192g citric acid were added to 2000mL of deionized water to prepare mixed solution A, and then 100g of pretreated carbon black was added to 200mL mixed solution A. And soak for 48 hours at 200°C and 1MPa high pressure to obtain material B;

[0071] 2) Preparation of carbon black / carbon nanotubes:

[0072] Put material B into a quartz boat and place it in the middle of the tube furnace, raise the temperature to 800°C under the protection of inert gas, keep it warm for 2 hours, then change it to hydrogen for 350 minutes, then keep it...

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