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1.
    
There is a great appeal to develop an omnipotent player combining lithium-ion batteries (LIBs) with the capacitive storage communities. Hybrid capacitors as a kind of promising energy storage device are attracting increasing attention in the main playground in recent years. Unlike supercapacitors (SCs) and LIBs, hybrid capacitors combine a capacitive electrode with a Faradaic battery electrode. In these hybrid cells, the capacitive electrode brings the power while the energy mainly comes from the Faradaic one. Numerous efforts have been conducted in the past decades; however, the research about hybrid capacitors is still at its infancy stage, and it is not expected to replace LIBs or SCs in the near future utterly. Here, the advances of hybrid capacitors, including insertion-type materials, lithium-ion capacitors, and sodium-ion capacitors, are reviewed. This review aims to offer useful guidance for the design of faradic battery electrodes and hybrid cell construction. Brief challenges and opportunities for future research on hybrid capacitors are finally presented.  相似文献   

2.
    
Antiferroelectric ceramics with extraordinary energy‐storage density have gained exponentially soaring attention for their applications in pulsed power capacitors. Nevertheless, high energy dissipation is a deficiency of antiferroelectric materials. The modulation of Ba/La‐doped (Pb0.91BaxLa0.06−2x/3)(Zr0.6Sn0.4)O3 (x = 0.015, 0.03, 0.045, 0.06) antiferroelectric ceramics is aimed at increasing the energy efficiency and obtaining an ideal energy storage density. The traditional solid‐state reaction is exploited for ceramics fabrication and all prepared samples exhibit an ultralow electrical hysteresis due to the local structural heterogeneity, as verified by Raman spectroscopy. Of particular importance is the fact that the (Pb0.91Ba0.045La0.03)(Zr0.6Sn0.4)O3 ceramic possesses an excellent recoverable energy storage density (Wrec = 8.16 J cm−3) and a remarkable energy efficiency (η = 92.1%) simultaneously under an electric field of 340 kV cm−1. Moreover, the corresponding ceramic exhibits a superior discharge current density (CD = 1498.6 A cm−2), a high level of power density (PD = 202.3 MW cm−3), and a nanosecond‐level discharge period (53 ns). This provides a promising antiferroelectric material for fabricating ceramic capacitors with excellent energy storage and high power characteristics.  相似文献   

3.
    
High-temperature dielectric polymers are in constant demand for the multitude of high-power electronic devices employed in hybrid vehicles, grid-connected photovoltaic and wind power generation, to name a few. There is still a lack, however, of dielectric polymers that can work at high temperature (> 150 °C). Herein, a series of all-organic dielectric polymer composites have been fabricated by blending the n-type molecular semiconductor 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTCDA) with polyetherimide (PEI). Electron traps are created by the introduction of trace amounts of n-type small molecule semiconductor NTCDA into PEI, which effectively reduces the leakage current and improves the breakdown strength and energy storage properties of the composite at high temperature. Especially, excellent energy storage performance is achieved in 0.5 vol.% NTCDA/PEI at the high temperatures of 150 and 200 °C, e.g., ultrahigh discharge energy density of 5.1 J cm−3 at 150 °C and 3.2 J cm−3 at 200 °C with high discharge efficiency of 85–90%, which is superior to its state-of-the-art counterparts. This study provides a facile and effective strategy for the design of high-temperature dielectric polymers for advanced electronic and electrical systems.  相似文献   

4.
    
Energy conversion and storage devices are highly desirable for the sustainable development of human society. Hybrid organic–inorganic perovskites have shown great potential in energy conversion devices including solar cells and photodetectors. However, its potential in energy storage has seldom been explored. Here the crystal structure and electrical properties of the 2D hybrid perovskite (benzylammonium)2PbBr4 (PVK-Br) are investigated, and the consecutive ferroelectric-I (FE1) to ferroelectric-II (FE2) then to antiferroelectric (AFE) transitions that are driven by the orderly alignment of benzylamine and the distortion of [PbBr6] octahedra are found. Furthermore, accompanied by field-induced AFE to FE transition near room temperature, a large energy storage density of ≈1.7 J cm−3 and a wide working temperature span of ≈70 K are obtained; both of which are among the best in hybrid AFEs. This good energy storage performance is attributed to the large polarization of ≈7.6 µC cm−2 and the high maximum electric field of over 1000 kV cm−1, which, as revealed by theoretical calculations, originate from the cooperative coupling between the [PbBr6] octahedral framework and the benzylamine molecules. The research clarifies the discrepancy in the phase transition character of PVK-Br and shed light on developing high-performance energy storage devices based on 2D hybrid perovskite.  相似文献   

5.
    
A facile method is reported to prepare highly conductive stretchable wavy reduced graphene oxide (rGO) films by in situ reducing blade‐coated graphene oxide films on elastic tapes. The sheet resistance of a 1.20 μm thick rGO film coated elastic tape is measured to be as low as 21 Ω sq−1 and it does not change during 1000 cycles of stretching/releasing with a maximum strain of 100%. The wavy rGO film can also be detached from its elastic substrate into a freestanding state, keeping its excellent elasticity. This in situ reduction method does not involve film transfer and high‐temperature annealing; thus it is convenient and scalable. A solid‐state electrochemical capacitor with these rGO electrodes shows large areal specific capacitance, and excellent electrochemical stability and flexibility.  相似文献   

6.
    
Ferroelectric memory is one of the most attractive emerging nonvolatile memory. Conventional methods to increase storage density in ferroelectrics include reducing the storage bit size or fabricating 3D stacks. However, the former will face a physical limit finally, and the integration of single-crystalline ferroelectric oxide following the latter still remains a great challenge. Here, a new method is introduced to construct a scroll-like 3D memory structure by self-rolling-up single-crystalline ferroelectric oxides. PbZr0.3Ti0.7O3 single-crystalline thin film is chosen as a prototype and epitaxially grown on another oxide stressor layer with a few lattice-mismatch. Releasing such “Pb(Zr, Ti)O3/stressor” bilayered structure from the substrate induces self-rolling-up due to the internal stress from the lattice-mismatch. High-density information can be written in the form of switched ferroelectric domains on those flat “Pb(Zr, Ti)O3/stressor” membranes via piezoelectric force microscopy. In self-rolling-up membranes, information density can be experimentally enhanced up to 45 times. Theoretically, the freestanding “Pb(Zr, Ti)O3/stressor” membranes have a strongly driven force to self-rolling-up, and the area ratio can enhance 100–450 times, corresponding to an ultra-high density information storage of 102 Tbit In−2. This study provides a new and general method to develop compact, high-density, and 3D memories from oxide materials.  相似文献   

7.
在＂电路理论＂课程暂态分析中,换路后两个电容直接并联,或两个电感直接串联,电容电压和电感电流不再服从换路定律,当电荷与磁链重新分配后满足电荷、磁链守恒,但静电场能量与磁场能量均有损失,看似系统能量不守恒。本文将从串联暂态电量、串联稳态电压整体、并联稳态电压分体和功率密度等角度分析了能量变化,最终从线损耗和电磁辐射两方面...  相似文献   

8.
    
Capacitors are ubiquitous and crucial components in modern technologies. Future microelectronic devices require novel dielectric capacitors with higher energy storage density, higher efficiency, better frequency and temperature stabilities, and compatibility with integrated circuit (IC) processes. Here, in order to overcome these challenges, a novel 3D HfO2 thin film capacitor is designed and fabricated by an integrated microelectromechanical system (MEMS) process. The energy storage density (ESD) of the capacitor reaches 28.94 J cm−3, and the energy storage efficiency of the capacitor is up to 91.3% under an applied electric field of 3.5 MV cm−1. The ESD can be further improved by reducing the minimum period structure size of the 3D capacitor. Moreover, the 3D capacitor exhibits excellent temperature stability (up to 150 °C) and charge-discharge endurance (107 cycles). The results indicate that the 3D HfO2 thin film MEMS capacitor has enormous potential in energy storage applications in harsh environments, such as pulsed discharge and power conditioning electronics.  相似文献   

9.
    
Films with excellent flexibility and mechanical stability are important for flexible and wearable devices. However, most films reported are prepared on substrates, and the synthesis of freestanding flexible films remains a challenge. Herein, a freestanding Bi2S3 nanofibrous membrane (NFM) is successfully prepared via a one-step hydrothermal method, which is self-assembled from ultralong Bi2S3 nanowires (NWs) over a length of millimeter-scale crisscrossing each other. Significantly, the Bi2S3 NFM can be bent or clipped into an arbitrarily desired form. Based on the freestanding Bi2S3 NFM, an IR photodetector is fabricated, depicting a robust responsivity of 2.23 (2.06) µA W−1 under 850 (940) nm illumination. The Bi2S3 NFM photodetector exhibits a relatively fast response time (47.1 ms), which is attributed to high-speed carrier transport efficiency in the NWs network. Under the bending states, the device still exhibits excellent detection performance, maintaining more than 86% of the initial photocurrent even after 1000 bending-flattening times. The robust photoresponse of the Bi2S3 NFM photodetector after 2 months of storage in air and after 1 week in the bending state illustrates its excellent air stability and flexible detection ability. Besides, the photodetector can clearly identify the target image, indicating widespread potential applications in flexible and wearable fields.  相似文献   

10.
    
Dielectric capacitors are widely studied for power supply systems because they can quickly store and release electrical energy. Among various kinds of dielectric materials, antiferroelectrics show promising features of high energy-storage density and efficiency. In this study, epitaxial antiferroelectric PbHfO3 films with different orientations are fabricated, in which remarkable anisotropies of polarization and energy storage properties are discovered. With the optimization of film orientation, much-improved energy density and excellent high-temperature efficiency are achieved in the PbHfO3 films. Moreover, the PbHfO3 films are fabricated onto flexible mica substrates, which exhibit excellent property robustness against mechanical bending. This study provides a fundamental understanding of the anisotropic antiferroelectric behaviors of epitaxial PbHfO3 films and provides a generalizable pathway for flexible energy-storage dielectric capacitors.  相似文献   

11.
    
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12.
    
Hybrid metal–organic frameworks (MOFs) demonstrate great promise as ideal electrode materials for energy‐related applications. Herein, a well‐organized interleaved composite of graphene‐like nanosheets embedded with MnO2 nanoparticles (MnO2@C‐NS) using a manganese‐based MOF and employed as a promising anode material for Li‐ion hybrid capacitor (LIHC) is engineered. This unique hybrid architecture shows intriguing electrochemical properties including high reversible specific capacity 1054 mAh g?1 (close to the theoretical capacity of MnO2, 1232 mAh g?1) at 0.1 A g?1 with remarkable rate capability and cyclic stability (90% over 1000 cycles). Such a remarkable performance may be assigned to the hierarchical porous ultrathin carbon nanosheets and tightly attached MnO2 nanoparticles, which provide structural stability and low contact resistance during repetitive lithiation/delithiation processes. Moreover, a novel LIHC is assembled using a MnO2@C‐NS anode and MOF derived ultrathin nanoporous carbon nanosheets (derived from other potassium‐based MOFs) cathode materials. The LIHC full‐cell delivers an ultrahigh specific energy of 166 Wh kg?1 at 550 W kg?1 and maintained to 49.2 Wh kg?1 even at high specific power of 3.5 kW kg?1 as well as long cycling stability (91% over 5000 cycles). This work opens new opportunities for designing advanced MOF derived electrodes for next‐generation energy storage devices.  相似文献   

13.
本文介绍了利用单片机来实现检测静电密度的原理和设计方法,在应用中表明,该电路的测量范围为：0-100μ C/m^3,获得良好的效果。  相似文献   

14.
    
Herein, the effect of the insertion of a thin dielectric HfO2:Al2O3 (HAO) layer at different positions in the Pt/0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 (BCZT)/Au structure on the energy storage performance of the capacitors is investigated. A high storage performance is achieved through the insertion of a HAO layer between BCZT and Au layers. The insertion of the dielectric layer causes a depolarization field which results in a high linearity hysteresis loop with low energy dissipation. The Pt/BCZT/HAO/Au capacitors show an impressive energy storage density of 99.8 J cm?3 and efficiency of 71.0%, at an applied electric field of 750 kV cm?1. Further, no significant change in the energy storage properties is observed after passing 108 switching cycles through the capacitor. The presence of resistive switching (RS) in leakage current characteristics confirms the strong charge coupling between ferroelectric and insulator layers. The same trend of the RS ratio and the energy storage performance with the variation of the architecture of the devices suggests that the energy storage properties can be improved through the charge coupling between the layers. By combining ferroelectrics and dielectrics into one single structure, the proposed strategy provides an efficient way for developing highly efficient energy storage capacitors.  相似文献   

15.
    
Ferroelectric (FE) capacitors exhibiting ultrahigh power densities are widely utilized as electrostatic energy storage devices in pulsed electronic devices. One approach to maximize the discharge energy density (Ud) of capacitors is to increase the breakdown strength (Eb) accompanied with high maximum polarization (Pm) while suppressing the energy loss. However, the inverse relationship between Eb and Pm challenges the simultaneous enhancement of Eb and Ud. To overcome this limitation, FE/relaxor FE (RFE) heterostructure capacitors composed of Co-doped BaTiO3 (BTCO) and Sn-doped BaTiO3 (BTS) epitaxial thin film layers to decouple the Eb and Pm values are fabricated and the simultaneous enhancement of the Eb and Ud up to 7.9 MV cm−1 and 117 J cm−3, respectively is achieved. The high Eb and Ud values can be attributed to the suppression of the leakage current at the BTCO/BTS interface, a narrower hysteresis loop contributed by the BTS, and high Pm and Eb from the BTCO layer. Additionally, the BTCO/BTS heterostructure capacitors exhibit excellent fatigue endurance of up to 108 cycles and are thermal stable even at 160 °C. Through properly designing the FE and RFE layers, thermally stable and reliable FE/RFE heterostructure capacitors exhibiting high Ud and Eb can be realized.  相似文献   

16.
    
To effectively enhance the energy density and overall performance of electrochemical capacitors (ECs), a new strategy is demonstrated to increase both the intrinsic activity of the reaction sites and their density. Herein, nickel cobalt phosphides (NiCoP) with high activity and nickel cobalt hydroxides (NiCo‐OH) with good stability are purposely combined in a hierarchical cactus‐like structure. The hierarchical electrode integrates the advantages of 1D nanospines for effective charge transport, 2D nanoflakes for mechanical stability, and 3D carbon cloth substrate for flexibility. The NiCoP/NiCo‐OH 3D electrode delivers a high specific capacitance of ≈1100 F g?1, which is around seven times higher than that of bare NiCo‐OH. It also possesses ≈90% capacitance retention after 1000 charge–discharge cycles. An asymmetric supercapacitor composed of NiCoP/NiCo‐OH cathode and metal–organic framework‐derived porous carbon anode achieves a specific capacitance of ≈100 F g?1, high energy density of ≈34 Wh kg?1, and excellent cycling stability. The cactus‐like NiCoP/NiCo‐OH 3D electrode presents a great potential for ECs and is promising for other functional applications such as catalysts and batteries.  相似文献   

17.
    
Miniaturization and light weight of aluminum electrolytic capacitor can be achieved via the enhancement in the specific capacitance of anodized aluminum foils resulted from the introduction of compounds with high permittivity into dielectric layer. However, the electrostatic repulsion between the compounds and aluminum substrates hinders this introduction of the compounds, leading to a limited improvement in the specific capacitance. In this work, a novel strategy has been developed to promote the deposition of TiO2 on the surface of aluminum foils by surface modification with polyvinyl alcohol, which sharply decreases the electrostatic repulsion and dramatically increases the mass of deposited TiO2. The evolution of composition and morphology during the process are studied and the capacitor performance of aluminum foils with various treatments is investigated. Interestingly, after surface modification, a specific capacitance of 131.5 µF cm?2 under the withstanding voltage of 21.2 V is obtained, and there is about 60% enhancement in the specific capacitance compared with those without TiO2, and about 30% enhancement compared with those without surface modification, respectively. The specific capacitance obtained is the highest one for aluminum electrolytic capacitor reported to date. These outstanding performances exhibit great potential of this strategy for commercial application on aluminum electrolytic capacitor.  相似文献   

18.
针对目前汽车减速时所产生的惯性动能利用率偏低的问题,通过了设计一种用于普通汽车的惯性动能回收再利用装置的方法,以超级电容和蓄电池并举的方式储存能量,将该能量的一部分用于起动加速助力,一部分用于车载电器供电;结合搭建的该新型惯性动能回收再利用装置模型仿真试验,绘制出了减速过程中该装置电压电流的输入和输出波形,得出该装置可简便、有效地回收普通汽车惯性动能,进而提高汽车能量利用率的结论.  相似文献   

19.
分析了各种特殊场合应用的铝电解电容器的不同作用,提出了相应的性能要求;同时,针对铝电解电容器设计制造过程中的要点,如铝箔、电解纸、电解液等选材原则,以及应采用的工艺和结构等等,作了较为详细的阐述。对铝电解电容器生产单位能更好地满足日新月异的电子技术变化要求提出了相应的解决办法。  相似文献   

20.
    
The excellent energy‐storage performance of ceramic capacitors, such as high‐power density, fast discharge speed, and the ability to operate over a broad temperature range, gives rise to their wide applications in different energy‐storage devices. In this work, the (Pb0.98La0.02)(Zr0.55Sn0.45)0.995O3 (PLZS) antiferroelectric (AFE) ceramics are prepared via a unique rolling machine approach. The field‐induced multiphase transitions are observed in polarization–electric field (P–E) hysteresis loops. All the PLZS AFE ceramics possess high energy‐storage densities and discharge efficiency (above 80%) with different sintering temperatures. Of particular significance is that an ultrahigh recoverable energy‐storage density of 10.4 J cm‐3 and a high discharge efficiency of 87% are achieved at 40 kV mm‐1 for PLZS ceramic with a thickness of 0.11 mm, sintered at 1175 °C, which are by far the highest values ever reported in bulk ceramics. Moreover, the corresponding ceramics exhibit a superior discharge current density of 1640 A cm‐2 and ultrafast discharge speed (75 ns discharge period). This great improvement in energy‐storage performance is expected to expand the practical applications of dielectric ceramics in numerous electronic devices.  相似文献   

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