A method for uniform distribution of PTFE binder and electrode key component materials and its application in the battery industry

Abstract

The invention discloses a method for uniform distribution of a PTFE (polytetrafluoroethylene) binder and electrode key component materials and an application in the battery industry. The method comprises the steps of carrying out ultrasonic dispersion or high-speed mechanical stirring on a water diluent of PTFE emulsion to obtain a solution 1; mixing conductive carbon powder, an electrode active component, a surfactant and water, then carrying out ultrasonic dispersion or high-speed mechanical stirring on the mixed solution to obtain a solution 2; preheating and mixing the solution 1 and the solution 2 to obtain a solution 3; carrying out high-speed stirring on the solution 3 for 1-6 hours under a constant temperature condition, standing and cooling to the room temperature so as to obtaina layered solid-liquid mixture; and removing a supernatant of the solid-liquid mixture to obtain a PTFE-conductive carbon powder-electrode active material ternary compound. The method realizes the uniform distribution of the binder, the conductive carbon powder and the electrode active material in an electrode, avoids the agglomeration of single component, improves the utilization ratio of the electrode active material and improves the discharge performance and operation stability of the battery; and the uniform distribution of each component in the electrode structure is obtained through preparing electrode slurry, there is no obvious secondary agglomeration, and the surface of the electrode is smooth, flat and free of obvious cracks.

Description

Background technique [0001] The structural formula of polytetrafluoroethylene (PTFE) is [CF 2 -CF 2 ] n , has excellent chemical stability and corrosion resistance, and is one of the best corrosion-resistant materials in the world today. In addition, PTFE has good aging resistance and excellent temperature resistance. It can be used at -180 o C and 250 o It can work stably for a long time in the temperature range of C, and can be widely used in aerospace, chemical, chemical, battery and other industries. PTFE is an important part of the positive and negative electrodes of various batteries. (1) The main function of PTFE in secondary electrode batteries such as nickel-metal hydride batteries and lithium-ion batteries and supercapacitors is to bond and connect the active components of the electrodes with the electrodes collectively, reduce the electrode impedance, and at the same time make the electrode sheets have good mechanical properties and machinability to meet the ne...

AI Technical Summary

Problems solved by technology

In the above-mentioned process of preparing electrode slurry based on physical mixing and stirring, due to the difference between the molecular structure of PTFE and the physical and chemical properties of the dispersed emulsion and the properties of the electrode powder itself, it is difficult to achieve an electrode obtained by preparing electrode slurry based on physical stirring and mixing. The uniform distribution of PTFE and electrode materials with water-repellent agent in the microscopic scale, PTFE resin and electrode materials are prone to secondary agglomeration during high-speed mechanical stirring, and the slurry is mostly agglomerated PTFE particles and electrode material aggregates Uneven mixing and distribution, agglomerated particles are prone to appear in the slurry, and the dispersion effect is poor, which not only affects the electrode coating quality, but also greatly affects the battery discharge performance and energy conversion efficiency

[0003] Therefore, it is urgent to develop a method for uniform distribution of PTFE and electrode materials used as electrode binders, and use it in electrochemical energy devices to solve the key problems of PTFE binders and electrodes in existing different battery electrode structures. Difficult to achieve uniform distribution among the technical status of the components

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