Superior Energy Storage Performances of Polymer Nanocomposites via Modification of Filler/Polymer Interfaces

Abstract

systems, they have numerous applications in various fields as pulsed power supply technology, [8,9] energy harvesting, [10][11][12] inverters, [13][14][15] and passive elements, [16][17][18] toward both defense and civil industries. Excellent energy storage capabilities of dielectric materials including high discharged energy density and high energy efficiency have long been eagerly pursued to meet the challenges and needs of the rapid development of modern industry, i.e., the low energy density of current dielectric materials results in overburdened capacitor volume and weight in electrical power systems. The energy storage performances of dielectric materials are usually multiply determined by three major electrical and dielectric parameters, which are categorized as:1) The breakdown strength E b ;2) The relative permittivity (also called dielectric constant) ε r or electric displacement D (the electric displacement is related to the polarization P by D = P + ε 0 E, here ε 0 = 8.85 × 10 −12 F m −1 is the vacuum permittivity); 3) The dielectric loss tanδ.In general, as illustrated in Figure 1, the discharged energy density of dielectric materials can be determined aswhere E is the applied electric field, and the energy efficiency is calculated by Dielectric polymer nanocomposites by integration of high-E b polymer matrix and high-D(ε r ) ceramic fillers have shown great potential for dielectric and energy storage applications in modern electronic and electrical systems. Interface between ceramic fillers and polymer matrix is considered as a predominant factor to determine the dielectric performances of the nanocomposites. This review analyzes the influence of the interface on dielectric responses and breakdown strength in the nanocomposites, and discusses the viability of current interface engineering strategies in improving their energy storage capabilities. Two scopes of current interface modification approaches are focused from both structural and functional considerations in the dielectric ceramics/polymer nanocomposites: first, the organic/inorganic interface compatibility can be modified to generate homogeneous dispersion of ceramic nanoparticles in polymer matrix, which is the premise of fully realizing the synergistic combination of advantages of polymer and ceramic fillers; second, regulated local electrical and dielectric behaviors in interface region enable the enhancement of dielectric properties (both high dielectric constant and high breakdown strength) in resultant nanocomposites. In the last part, some present challenges and future perspectives are proposed to utilize the interface strategy for developing high energy density ceramics/ polymer nanocomposites for dielectric and energy storage applications.

Phase-field modeling and machine learning of electric-thermal-mechanical breakdown of polymer-based dielectrics

“…While increasing the loading electric field can effectively enhance the amount of energy stored in a dielectric, the probability of breaking down the dielectrics catastrophically increases as well. Despite tremendous efforts have been invested to understand the dielectric breakdown mechanism 7–10 , the dielectric breakdown is still among the least understood physical phenomena due to the complex electrical, thermal, mechanical, and chemical interactions within a composite dielectric.…”

The acquirement of desirable dielectric properties of carbon nanofiber composites based on the controlled crystallization

“…The percolation theory is described into the following equations by the power law 27,28 : dielectric constant of composites. [29][30][31] But in this paper, the interfacial effect between CNFs and HDPE was weak, and the dielectric constant resulting from interfacial polarization effect was not dominated.…”

3D printing of anisotropic polymer nanocomposites with aligned BaTiO3 nanowires for enhanced energy density

“…High performance dielectric capacitors have been widely applied in electrical and electronic systems, such as electric vehicles, wind generators and aerospace power conditioning, due to their merits of super high power density and ability to withstand high operating voltage. [1][2][3][4][5][6][7] The dielectric materials used in commercially available capacitors are mainly based on biaxially oriented polypropylenes (BOPP), which exhibit energy densities of only 1-1.2 J cm À3 at high applied electric field (B640 kV mm À1 ). 8 In this case, the low energy density of the dielectric becomes a limitation to their applications.…”