Enhanced High-Temperature Capacitive Energy Storage by 0.55Bi_0.5Na_0.5TiO₃-0.45(Bi_0.2Sr_0.7)TiO₃ Nanofibers in Polyetherimide Nanocomposites

Abstract

The low discharge energy density and operation temperature of dielectrics limit the integration application of capacitors under extreme environment conditions. In order to reduce the dielectric loss of Bi 0.5 Na 0.5 TiO 3 , 0.55Bi 0.5 Na 0.5 TiO 3 -0.45(Bi 0.2 Sr 0.7 )TiO 3 (BNT-BST) nanofibers with optimized diameter were synthesized and utilized to improve the high-temperature capacitive energy storage of polyetherimide (PEI) nanocomposites. Benefiting from the introduction of nanofibers, the leakage current is significantly reduced and charge migration is limited, contributing to the enhancement of the energy storage properties. For example, the leakage current density of the 3 wt % BNT-BST/PEI nanocomposite is suppressed from 0.136 μA/cm 2 of PEI to 0.056 μA/cm 2 at 250 kV/mm. The nanocomposite with 3 wt % BNT-BST achieves an excellent discharge energy density of 10.37 J/cm 3 at 560 kV/mm, which is 65.4% higher than that of PEI. When the environment temperature is up to 100 °C, the discharge energy density of the nanocomposite maintains a high level of 4.76 J/cm 3 . Furthermore, the nanocomposite displays outstanding cycling stability and fast charge−discharge performance. For instance, after 10 6 charge−discharge cycles at 150 kV/mm, the discharge energy density and efficiency remain at 99 and 95% of the initial values, respectively. This work provides a feasible idea for achieving high-energy density nanocomposites under high environment temperature.

Significantly Enhanced Energy Density of Polyvinylidene Fluoride/Polyimide-Based Nanocomposites by Core–Shell BaTiO3@SiO2

“…From the perspective of improving ε r , scholars have proposed 0–3 type ceramic/polymer composite materials. Numerous studies have shown that this model of composite material is the most direct and effective in improving dielectric and energy storage properties ,,,,− and is an ideal dielectric material for energy storage applications. In addition to the connectivity between the two, the properties of the composite films are largely influenced by several variables, such as the properties of the polymer matrix (semicrystalline, amorphous, etc.…”

“…In addition to the connectivity between the two, the properties of the composite films are largely influenced by several variables, such as the properties of the polymer matrix (semicrystalline, amorphous, etc. ), the size of the ceramic filler (micrometer, nanometer), the dimensionality of the ceramic filler (zero-dimensional, one-dimensional ,,, ), and the method of preparation used (spin-coating, ,,− , hot-pressing, etc.). Recently, ternary composite ceramic/polymer composite films (zero-dimensional fillers doped into blended polymers) have been reported. ,− For example, Liu et al prepared a PVDF/PMMA/TiO 2 composite film by melting, blending, and blow molding processes.…”

“…Some studies have pointed out that the interfacial region between ceramics and polymers has a direct impact on the change of dielectric properties and energy-storing characteristics of nanocomposites. , In other words, an outstanding ceramic–polymer interface is the key link to obtain superior dielectric properties and energy-storage characteristics of nanocomposites. From the perspective of optimizing the interface of ceramic/polymer composites, researchers have done lots of work in regulating the interfacial quality between the two phases. ,,,,− ,− For the more widely studied 0–3 ceramic/polymer composites, cladding an insulating layer with moderate dielectric properties on the ceramic surface modulates the dielectric mismatch at the two-phase interface and relieves the concentration of the local electric field. This proved to be a generalized strategy for obtaining a high- E b , high-quality interface.…”

Improved Dielectric and Energy Storage Properties of Polypropylene-Based Organic Films through Construction of a Microcompatible “Sea–Island” Structure

“…The rapid development of modern power electronics technology has put forward higher requirements for the energy storage performance of capacitors. Polymer-based thin film capacitors play an essential role in modern electronic equipment and electricity systems due to the advantages of rapid discharge rate, high voltage resistance, high reliability, lightweight, and low cost. − For example, the most common commercial film capacitors use bioriented polypropylene (BOPP) as the dielectric material and the capacitors behave with low dielectric loss (∼0.0003), high breakdown strength (∼600 MV/m), and ultrahigh room temperature charge/discharge efficiency (>90%). However, the low dielectric constant (∼2.2) of PP makes it difficult to improve the energy storage density (∼2 J/cm 3 ) of thin film capacitors, which has become an obstacle for miniaturization, integration, and high functionality of the electronic and electrical equipment.…”