Linear dielectric/high-entropy sandwich structure design enables high capacitive energy storage

Designing the fine-grained ceramics with high recoverable energy storage density and excellent mechanical performance, still presents great challenges. Because the ceramics with large pore size and low relative density were obtained by the traditional sintering method, they always exhibit small breakdown strength and poor mechanical properties, which limits the miniaturization and operation of devices in harsh environments. In this paper, we designed the barium titanate ceramics (BT) ceramics with grain size of 252 nm and relative density of 0.92 can be obtained via co-sintering of two sizes of BT particles at 1000 °C for 10 h. The cubic phase BT particles with 80 nm are doped in the tetragonal phase BT particles with 200 nm to obtain tetragonal phase fine-grained BT ceramics. When doped with 80 nm BT particles, the sintering of 200 nm BT particles is promoted. The enhanced sinterability is due to the phase transformation and metastability, which act as sintering aids. The obtained BT ceramics with nanodomains, high energy storage and mechanical properties. The discharge energy density is of 0.81 J/cm3, and the Vickers hardness is 1.75 GPa.

High energy storage properties of lead-free Mn-doped (1-x)AgNbO3-xBi0.5Na0.5TiO3 antiferroelectric ceramics

Ni-modified BaTiO3 film prepared by sol-gel with high energy storage performance

Achieving high energy storage density in BaTiO3- (Bi0.5Li0.5)(Ti0.5Sn0.5)O3 lead-free relaxor ferroelectric ceramics

The importance of electroceramics is well-recognized in applications of high energy storage density of dielectric ceramic capacitors. Despite the excellent properties, lead-free alternatives are highly desirous owing to their environmental friendliness for energy storage applications. Herein, we provide a facile synthesis of lead-free ferroelectric ceramic perovskite material demonstrating enhanced energy storage density. The ceramic material with a series of composition (1-z) (0.94Na0.5Bi0.5TiO3-0.06BaTiO3)-zNd0.33NbO3, denoted as NBT-BT-zNN, where, z = 0.00, 0.02, 0.04, 0.06, and 0.08 are synthesized by the conventional solid-state mix oxide route. Microphases, microstructures, and energy storage characteristics of the as-synthesized ceramic compositions were determined by advanced ceramic techniques. Powder X-ray diffraction analysis reveals pure single perovskite phases for z = 0 and 0.02, and secondary phases of Bi2Ti2O7 appeared for z = 0.04 and 0.08. Furthermore, scanning electron microscopy analysis demonstrates packed-shaped microstructures with a reduced grain size for these ceramic compositions. The coercive field (Ec) and remnant polarization (Pr) deduced from polarization vs. electric field hysteresis loops determined using an LCR meter demonstrate decreasing trends with the increasing z content for each composition. Consequently, the maximum energy storage density of 3.2J/cm3, the recoverable stored energy of 2.01J/cm3, and the efficiency of 62.5% were obtained for the z content of 2mol% at an applied electric field of 250kV/cm. This work demonstrates important development in ceramic perovskite for high power energy storage density and efficiency in dielectric capacitors in high-temperature environments. The aforementioned method makes it feasible to modify a binary ceramic composition into a ternary system with highly enhanced energy storage characteristics by incorporating rare earth metals with transition metal oxides in appropriate proportions.

Ceramic‐polymer nanocomposites with high energy storage density can achieve excellent energy storage performance and have a wide range of application prospects. Currently, it has been shown that the coupling effects have a great impact on improving the performance of dielectric composites, but increasing the breakdown strength of polymer nanocomposite is still a tremendous challenge to the achievement of high energy density under high voltages. The aim of this paper is to further investigate this problem and obtain AgNbO3/PVDF flexible composites by introducing a small amount of AgNbO3 ultrafine powder prepared by hydrothermal method into poly(vinylidene fluoride) (PVDF). The interfacial coupling effect within this nanocomposite with the coupling effects of nonlinear dielectric materials improves its energy storage capacity and electrical strength resistance. The energy density of the 2 wt% AgNbO3/PVDF composite film was raised to 16.5 J/cm3 at the electric breakdown strength of 391.7 MV/m, and its energy storage capacity is two to three times that of AgNbO3 lead‐free antiferroelectric ceramics. Finite element simulations showed the further enhancement of breakdown strength was ascribed to the local electric field and to the AgNbO3 ultrafine powder which blocked the breakdown path in the nanocomposites and coupling effects occurred with PVDF. Hence, the AgNbO3 ultrafine powder has a positive effect on improving the energy storage performance of flexible composites. The effects of nonlinear dielectric material coupling effects and interfacial coupling effects on the dielectric properties of composite dielectric materials are further investigated, which are important for the development of flexible high energy storage capacitors.

As an important energy storage device, high energy storage capacitors have been widely used in electric vehicles, drones, new manufacturing of robots, wind power generation, smart grid and other energy fields. Among them, ternary system high energy storage capacitor has been widely concerned and studied because of its unique advantages. This paper summarizes the application prospect and the significance of research and development of high energy storage capacitors, introduces the basic principle and classification of high energy storage capacitors, and expounds the research status and existing problems of ternary system high energy storage capacitors. And the future development trend of ternary system high energy storage capacitors is briefly analyzed, and the main influencing factors and key nodes of research and development of ternary system high energy storage capacitors are summarized. As one of the important development directions in the field of energy storage and power transmission in the future, the main characteristics and broad application prospects of ternary system high energy storage capacitors are discussed and prospected. We look forward to greater breakthroughs in improving energy storage density, reducing costs, and improving charge and discharge speed and cycle life. At the same time, the emergence of new materials and manufacturing processes will also promote the further development and application of three-ring system high-energy storage capacitors.

High and ultra-stable energy storage from all-carbon sodium-ion capacitor with 3D framework carbon as cathode and carbon nanosheet as anode

With the development of science and technology, polymer dielectric capacitors are widely used in energy, electronics, transportation, aerospace, and many other areas. For polymer dielectric energy storage capacitors to remain effective in practical applications, excellent charge and discharge performance is essential. However, the performance of the common polymer dielectric capacitors will deteriorate rapidly at high temperature, which makes them fail to work efficiently under worse working conditions. Dielectric trap energy levels and trap densities increase when nanoparticles are incorporated into the dielectric. The change in trap parameters will affect carrier transport. Therefore, the high temperature energy storage performance of polymer nanocomposite dielectric can be improved by changing the trap parameters to regulate the carrier transport process. However, the quantitative relationship between trap energy level and trap density and the energy storage properties of nanocomposite dielectric need further studying. In this paper, the energy storage and release model for exponentially distributed trapped charge jump transport in linear polymer nanocomposite dielectrics is constructed and simulated. The volume resistivity and electric displacement-electric field loops of pure polyetherimide are simulated at 150 ℃, and the simulation results match the experimental results, which demonstrates the validity of the model. Following that, under different temperatures and electric fields, the current density, electric displacement-electric field loops, discharge energy density and charge-discharge efficiency of polyetherimide nanocomposite dielectric are simulated by using different trap parameters. The results show that increasing the maximum trap energy level and the total trap density can effectively reduce the carrier mobility, current density and conductivity loss, and enhance the discharge energy density and the charge-discharge efficiency of the nanocomposite dielectric. On condition that temperature is 150 ℃ and applied electric field is 550 kV/mm, the polyetherimide nanocomposite dielectric with a maximum trap energy level of 1.0 eV and a total trap density of 1×10<sup>27</sup> m<sup>–3</sup>, has 4.26 Jcm<sup>–3</sup> of discharge energy density and 98.93% of energy efficiency. These parameters in the polyetherimide nanocomposite dielectric are 91.09% and 227.58% higher than those in the pure polyetherimide, respectively. The energy storage performance under high temperature and high electric field is obviously improved. It provides theoretical and model support for the research and development of capacitors with high temperature resistance and energy storage performance.

With the development of science and technology, polymer dielectric capacitors are widely used in energy, electronics, transportation, aerospace, and many other areas. For polymer dielectric energy storage capacitors to remain effective in practical applications, excellent charge and discharge performance is essential. However, the performance of the common polymer dielectric capacitors will deteriorate rapidly at high temperature, which makes them fail to work efficiently under worse working conditions. Dielectric trap energy levels and trap densities increase when nanoparticles are incorporated into the dielectric. The change in trap parameters will affect carrier transport. Therefore, the high temperature energy storage performance of polymer nanocomposite dielectric can be improved by changing the trap parameters to regulate the carrier transport process. However, the quantitative relationship between trap energy level and trap density and the energy storage properties of nanocomposite dielectric need further studying. In this paper, the energy storage and release model for exponentially distributed trapped charge jump transport in linear polymer nanocomposite dielectrics is constructed and simulated. The volume resistivity and electric displacement-electric field loops of pure polyetherimide are simulated at 150 ℃, and the simulation results match the experimental results, which demonstrates the validity of the model. Following that, under different temperatures and electric fields, the current density, electric displacement-electric field loops, discharge energy density and charge-discharge efficiency of polyetherimide nanocomposite dielectric are simulated by using different trap parameters. The results show that increasing the maximum trap energy level and the total trap density can effectively reduce the carrier mobility, current density and conductivity loss, and enhance the discharge energy density and the charge-discharge efficiency of the nanocomposite dielectric. On condition that temperature is 150 ℃ and applied electric field is 550 kV/mm, the polyetherimide nanocomposite dielectric with a maximum trap energy level of 1.0 eV and a total trap density of 1×10<sup>27</sup> m<sup>–3</sup>, has 4.26 J·cm<sup>–3</sup> of discharge energy density and 98.93% of energy efficiency. Compared with pure polyetherimide, the rate of improvement is 91.09% and 227.58%, respectively. The energy storage performance under high temperature and high electric field is obviously improved. It provides theoretical and model support for the research and development of capacitors with high temperature resistance and energy storage performance.

Bi(Mg2/3Nb1/3)O3 addition inducing high recoverable energy storage density in lead-free 0.65BaTiO3-0.35Bi0.5Na0.5TiO3 bulk ceramics

The HiTES energy storage is a high temperature thermal electric energy storage. It consists of a heating coil, a heat storage and a recuperated hot air turbine. HiTES can be applied to smooth out intermittency due to renewable energy sources, for load control, or other flexibility options. The low investment cost and the high efficiency make the HiTES energy storage economically feasible even today. The economic feasibility can be increased by improvements of the round trip efficiency and by decreasing investment costs. For that reason several improvements scenarios were analyzed. The most correct comparison between different energy storage systems is based on the levelized cost of the electricity storage — LCOES. It shows that HiTES is more economic than lithium ion batteries. The paper gives a short parametric analysis of the main parameters that influence the levelized cost of energy storage, like the specific investment cost, the round-trip efficiency and the price of the input electricity.

Tailoring properties of (Bi0.51Na0.47)TiO3 based dielectrics for energy storage applications

High energy storage density and stable fatigue resistance of Na0.46Bi0.46Ba0.05La0.02Zr0.03Ti0.97-xSnxO3 ceramics

A comprehensive study of Bi2Sr2Co2Oy misfit layered oxide as a supercapacitor electrode material