All-organic nanometer composite film with high energy storage density and preparation method thereof

Abstract

The invention relates to an all-organic composite film with high energy storage density and a preparation method thereof. The composite film provided by the invention consists of 95 to 99 volume percent of polyvinylidene fluoride (PVDF) serving as a substrate and 1 to 5 volume percent of conductive polyaniline (PANI) serving as a filler. The preparation method comprises the following steps of: mixing PANI powder, PVDF and DMF serving as a solvent, performing ball milling for 12+ / -1 hours, coating precursor solution on a glass plate, and drying at the temperature of 60+ / -1 DEG C for 2+ / -0.1 hours to obtain the all-organic composite film with high energy storage density and the thickness of 25 to 30mu m. The composite film provided by the invention has the advantages of high dielectric property, compressive strength and energy storage density.

Description

technical field [0001] The invention belongs to the technical field of dielectric composite material preparation, and in particular relates to a high energy storage density all-organic nanocomposite film with high energy storage density, low composite temperature and simple preparation process and a preparation method thereof. Background technique [0002] In order to obtain high-performance energy storage capacitors, many researchers focus on the preparation of high energy storage density dielectric materials. Since the energy storage density is proportional to the relative dielectric constant and the square of the compressive strength of the material, the preparation of composite dielectric materials with both high dielectric constant and high compressive strength has become a research hotspot in this field. At present, there are three main types of energy storage dielectric materials: (1) ceramic materials, such as: barium carbonate (BaTiO 3 ) can be made into ceramic th...

AI Technical Summary

Problems solved by technology

At present, there are three main types of energy storage dielectric materials: (1) ceramic materials, such as: barium carbonate (BaTiO 3 ) can be made into ceramic thin films by chemical solution deposition, and the dielectric constant is as high as 2500 (J.Ihlefeld, B.Laughlin, A.Hunt-Lowery, et al, J.Electroceram.2005, 14, 95.), but ceramic materials need Higher sintering temperature, which destroys the substrate material of the capacitor

(2) Polymer materials, such as: biaxially oriented polypropylene (BOPP) have a high compressive strength (640MV / m), but a small dielectric constant (2.2) results in an energy storage density of only 1.2J / cm 3 (M.Rabuffi, G.Picci, IEEE Trans.Plasma Sci.2002, 30, 1939.), limiting its application in energy storage capacitors

However, the disadvantage of this method is that the dielectric constant of the composite material increases slowly with the increase of the filling amount of the ceramic material, and when the filling amount of the ceramic material is too high, it is easy to damage the mechanical properties of the composite material

Moreover, the dielectric constant of the filler and the matrix is ​​quite different. When subjected to an external electric field, an inhomogeneous electric field will be generated inside the composite material, which will greatly reduce the compressive strength of the composite material.

Images