Improved Energy Storage Performance of All-Organic Composite Dielectric via Constructing Sandwich Structure.

Mengjia Feng,Qingquan Lei,Qingguo Chi,Chunhui Song,Changhai Zhang,Yue Zhang,Qingguo Chen,Tiandong Zhang,Yu Feng

doi:10.3390/polym12091972

Mengjia Feng, Qingquan Lei + Show 7 more

Open Access

https://doi.org/10.3390/polym12091972

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Journal: Polymers	Publication Date: Aug 31, 2020
Citations: 28	License type: CC BY 4.0

Affiliation: Harbin University of Science and Technology

Abstract

Improving the energy storage density of dielectrics without sacrificing charge-discharge energy storage efficiency and reliability is crucial to the performance improvement of modern electrical and electronic systems, but traditional methods of doping high-dielectric ceramics cannot achieve high energy storage densities without sacrificing reliability and storage efficiency. Here, an all-organic energy storage dielectric composed of ferroelectric and linear polymer with a sandwich structure is proposed and successfully prepared by the electrostatic spinning method. Additionally, the effect of the ferroelectric/linear volume ratio on the dielectric properties, breakdown, and energy storage is systematically studied. The results show that the structure has good energy storage characteristics with a high energy storage density (9.7 J/cm3) and a high energy storage efficiency (78%). In addition, the energy storage density of the composite dielectric under high energy storage efficiency (90%) is effectively improved (25%). This result provides theoretical analysis and experience for the preparation of multilayer energy storage dielectrics which will promote the development and application of energy storage dielectrics.

Highlights

Dielectric capacitors are widely used in pulsed power electronics and new energy vehicles due to their high power density and ultrashort discharge time [1,2,3,4]
The results showed that the composite dielectric has a high energy storage density of 9.7 J/cm3 when the volume ratio of PVTC is 10 vol %
It is worth noting that in order to prevent the diffusion at the interface, the parameters of hot pressing, namely hot-pressing temperature and hot-pressing time, need to be controlled and a temperature (175 ◦ C) at which polymethyl methacrylate (PMMA) melts but PVTC

Summary

Introduction

Dielectric capacitors are widely used in pulsed power electronics and new energy vehicles due to their high power density and ultrashort discharge time [1,2,3,4]. The required properties for capacitor dielectrics, such as high energy storage density, high breakdown strength, and low dielectric losses, are often difficult to obtain in a polymer material at the same time. To fill the theoretical gap mentioned above, in this study the linear polymer polymethyl methacrylate (PMMA) and the ferroelectric polymer P(VDF-TrFE-CFE) (PVTC) were employed to prepare the sandwich-structure composite dielectrics. A series of sandwich-structured dielectrics with PVTC and PMMA volume ratios of 1:9, 3:7, 5:5, 7:3, and 9:1, which are denoted as 1-9, 3-7, 5-5, 7-3, and 9-1 in the following text, were prepared and their dielectric, breakdown, and energy-storage characteristics were systematically studied. The 1-9 sandwich-structure PVTC/PMMA composite dielectric is able to maintain an energy storage density of 2.5 J/cm when the energy storage efficiency is. The study of sandwich-structured composite dielectric with outstanding energy storage properties could be a potential direction in the field of energy storage

Material and Methods

Results and Discussion

Microstructure and Properties Characterization

Conclusions