All Polymer Dielectric Films for Achieving High Energy Density Film Capacitors by Blending Poly(Vinylidene Fluoride-Trifluoroethylene-Chlorofluoroethylene) with Aromatic Polythiourea

Abstract

Construct dielectric films with high energy density and efficiency are the key factor to fabricate high-performance dielectric film capacitors. In this paper, an all organic composite film was constructed based on high dielectric polymer and linear dielectric polymer. After the optimized polycondensation reaction of a linear dielectric polymer aromatic polythiourea (ArPTU), the proper molecular weight ArPTU was obtained, which was introduced into poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) (PVDF-TrFE-CFE) terpolymer for a composite dielectrics. The results indicate that the addition of ArPTU molecules reduces the dielectric loss and improves the breakdown field strength of the PVDF-TrFE-CFE effectively. For the PVDF-TrFE-CFE/ArPTU (90/10) composite film, the maximum energy density about 22.06 J/cm 3 at 407.57 MV/m was achieved, and high discharge efficiency about 72% was presented. This composite material can be casted on flexible substrate easily, and PVDF-TrFE-CFE/ArPTU organic composite films having high energy density, high breakdown field strength, low dielectric loss, and higher discharge efficiency are obtained. This is an unreported exploration about high energy density organic dielectric films based on PVDF-TrFE-CFE matrix and linear polymer dielectrics, and the findings of this research can provide a simple and scalable method for producing flexible high energy density materials for energy storage devices.

Prospects for the Development of High Energy Density Dielectric Capacitors

“…The literature indicates that many approaches [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] have been used to increase the dielectric constant of polymer composites with some success. However, the magnitude of the increase in dielectric constant achieved varied greatly from paper to paper, even for the same approach.…”

“…There have been many studies [16][17][18][19] of combining two or more polymers with the objective of attaining a composite with properties more optimum for energy storage. That is a higher dielectric constant, lower loss tangent, and more linear behavior at high voltages.…”

“…That is a higher dielectric constant, lower loss tangent, and more linear behavior at high voltages. As an example [16], PDVF, which has a high dielectric constant, but relatively high losses and limited voltage linearity, is usually combined with other polymers to obtain a composite polymer with improved loss and voltage linearity than PDVF. Mixing/blending of polymers is not as simple a process as the term would imply as the mixing takes place on a nanoscale with the configuration/spacing of the different polymer molecules being difficult to predict and measure [17][18][19].…”

Composite of aromatic polythiourea/BaTiO3 nanowires with high energy density and high discharge efficiency for energy storage applications

“…The ArPTU synthesis process utilizes the polycondensation reaction of MDA and PDTC in NMP solution [8][9][10][11].First, 20 ml of NMP solution was introduced into a sample bottle. Then, 0.005 mol of MDA was introduced into the NMP solution.…”

Effect of Composition on Polarization Hysteresis and Energy Storage Ability of P(VDF-TrFE-CFE) Relaxor Terpolymers

“…Small remanent polarization and slim hysteresis make P(VDFx-TrFE1-x-CFEy) terpolymers attractive for energy storage applications [18,19]. A large electrocaloric effect was Therefore, polymers exhibiting high polarizability such as ferroelectric polyvinylidene fluoride P(VDF) and its copolymers with trifluoroethylene (TrFE), hexafluoropropylene (HFP), chlorofluoroethylene (CFE), and chlorotrifluoroethylene (CTFE), as well as blends between them or with other linear dielectric polymers, were studied for energy storage applications [5][6][7][8]. Ideally, all this stored energy should berecoverable, which entails that a remanent contribution to polarization should be small.…”