CN-116190653-B - High-solid-content conductive slurry and preparation method thereof

Abstract

The invention discloses high-solid-content conductive slurry which comprises a conductive agent, a thickening agent and a solvent, wherein the thickening agent is formed by polymerizing a monomer A and a monomer B. Also discloses a preparation method of the high-solid-content conductive slurry. The ionic liquid structure and the sulfonic acid group are introduced into the conductive slurry prepared by the invention, so that the impedance of the electrode plate can be reduced, the ionic conductivity of the electrode plate can be improved, the multiplying power performance of the battery can be improved, the adhesive force of the electrode plate can be increased, the consumption of adhesive can be reduced, the duty ratio of active materials can be improved, and the energy density of the battery can be further increased.

Inventors

• ZHUGE FUCHANG
• LIU YUMEI
• HE DONGHONG
• HU XIAOPING

Assignees

• 甘肃大象能源科技有限公司

Dates

Publication Date

20260508

Application Date

20230208

Claims (6)

1. 1. The high-solid-content conductive paste is characterized by comprising a conductive agent, a thickening agent and a solvent, wherein the thickening agent is formed by polymerizing a monomer A and a monomer B, the mass ratio of the monomer A to the monomer B is 1-4:1, and the structural formula of the monomer A is one or more of formulas I, II and III; 、 、 ; wherein R, R, R2 are selected from-ch=ch2, -C (CH 3) =ch2; the structural formula of the monomer B is shown in a formula IV;
2. 2. The high-solid-content conductive paste according to claim 1, wherein the conductive agent is one or more of graphene, carbon nanotubes, conductive carbon fibers, conductive carbon black, and conductive graphite.
3. 3. The high-solid-content conductive paste according to claim 1, wherein the mass ratio of the conductive agent, the thickener and the solvent is 1-10:1-5:84-97.
4. 4. A method for preparing the high-solid-content conductive paste according to any one of claims 1 to 3, comprising the steps of: S1, adding a conductive agent into a mixed solution of deionized water and ethanol for mixing to prepare a conductive suspension, then adding the conductive suspension into a high-pressure homogenizer for setting pressure operation time, transferring into a stirring container, adding a monomer A, stirring for 1-3 h, and drying to obtain a modified conductive agent; And S2, adding the modified conductive agent prepared by the monomers B and S1 into a solvent, fully stirring, then raising the temperature to 50-80 ℃, adding an azodiisobutyronitrile initiator, and continuously stirring for 1-10 hours to obtain the conductive paste.
5. 5. The method for preparing a high-solid-content conductive paste according to claim 4, wherein the operation pressure of the high-pressure homogenizer in the step S1 is 50 to 200mpa.
6. 6. The method for preparing a high-solid-content conductive paste according to claim 4, wherein the operation time of the high-pressure homogenizer in step S1 is 30 to 120min.

Description

High-solid-content conductive slurry and preparation method thereof Technical Field The invention relates to the technical field of lithium ion battery materials, in particular to high-solid-content conductive slurry and a preparation method thereof. Background The conductive agent mainly has the function of forming a conductive network structure in the electrode plate of the lithium ion battery, and improves the conductivity of the electrode plate, so that the conductive agent is used as an important component of the lithium ion battery, and greatly influences the performance of the lithium ion battery. However, in the current stage, in order to meet the dispersion effect of the conductive agent in the slurry, the prepared conductive slurry has lower solid content, which is not beneficial to the processing of electrode plates, and once the solid content is improved, the conductive agent is seriously agglomerated, the dispersion effect is not ideal, especially the middle-high-end conductive agent slurry, if the dispersion is not well done, the conductive agent with strong conductive performance is also not good in the application of the lithium battery. Therefore, there is a need to develop a higher solids conductive paste to meet the current needs. Disclosure of Invention In view of the above, the invention aims to overcome the defects in the prior art, provide a high-solid-content conductive paste with good dispersibility, and also provide a preparation method of the conductive paste. In order to achieve the above purpose, the invention adopts the following technical scheme: The high-solid-content conductive paste comprises a conductive agent, a thickening agent and a solvent, wherein the thickening agent is formed by polymerizing a monomer A and a monomer B, and the structural formula of the monomer A is one or more of formulas I, II and III; wherein R, R, R2 are selected from-ch=ch2, -C (CH 3) =ch2; the structural formula of the monomer B is shown in a formula IV; preferably, the conductive agent is one or more of graphene, carbon nanotubes, conductive carbon fibers, conductive carbon black and conductive graphite. Preferably, the mass ratio of the conductive agent to the thickener to the solvent is 1-10:1-5:84-97. Preferably, the mass ratio of the monomer A to the monomer B is 1-4:1. The preparation method of the high-solid-content conductive slurry comprises the following steps: S1, adding a conductive agent into a mixed solution of deionized water and ethanol for mixing to prepare a conductive suspension, then adding the conductive suspension into a high-pressure homogenizer for setting pressure operation time, transferring into a stirring container, adding a monomer A, stirring for 1-3 h, and drying to obtain a modified conductive agent; And S2, adding the modified conductive agent prepared by the monomers B and S1 into a solvent, fully stirring, then raising the temperature to 50-80 ℃, adding an azodiisobutyronitrile initiator, and continuously stirring for 1-10 hours to obtain the conductive paste. Preferably, the operation pressure of the high-pressure homogenizer in the step S1 is 50-200 MPa. Preferably, the running time of the high-pressure homogenizer in the step S1 is 30-120 min. The beneficial effects of the invention are as follows: the conductive agent is fully dispersed under the high pressure action of the high pressure homogenizer, and the monomer A is further combined with the conductive agent in a non-covalent bond way, so that secondary aggregation of the conductive agent is prevented, and the dispersibility of the conductive paste is improved. The monomer A and the monomer B are subjected to in-situ free radical polymerization under the action of the initiator to form a thickening agent, so that the conductive agent is prevented from sedimentation, the dispersibility and stability of the conductive agent are further improved, the solid content of the conductive paste and the compatibility with a polymer are also improved, and the processability of the pole piece is further improved. The ionic liquid structure and the sulfonic acid group are introduced into the conductive slurry, so that the impedance of the electrode plate can be reduced, the ionic conductivity of the electrode plate can be improved, the multiplying power performance of the battery can be improved, the adhesive force of the electrode plate can be increased, the consumption of adhesive can be reduced, the duty ratio of active materials can be improved, and the energy density of the battery can be further increased. Detailed Description The invention is further described below with reference to examples. Example 1: a high-solid conductive slurry comprises conductive carbon black, carbon nanotubes, a thickener and a solvent, wherein the thickener is formed by polymerizing a monomer A and a monomer B, The structural formula of the monomer A isR is-ch=ch2. The structural formula of the monomer B is shown as follows: The