Flexible asymmetric supercapacitors with excellent electrochemical performance and aesthetic property are realized by using ultrathin two-dimensional (2D) MnO2 and graphene nanosheets as cathode and anode materials, respectively. 2D MnO2 nanosheets (MSs) with a thickness of ca. 2 nm are synthesized with a soft template method for the first time, which achieve a high specific capacitance of 774 ...

We attempt to meet the general design requirements for high-performance supercapacitor electrodes by combining the strategies of lightweight substrate, porous nanostructure design, and conductivity modification. We fabricate a new type of 3D porous and thin graphite foams (GF) and use as the light and conductive substrates for the growth of metal oxide core/shell nanowire arrays to form integra...

UNLABELLED We describe a facile, low-cost, and green method to fabricate porous graphene networks/nickel foam (PG/NF) electrodes by electrochemical deposition of graphene sheets on nickel foams (NFs) for the application of supercapacitor electrodes. The electrodeposition process was accomplished by electrochemical reduction of graphene oxide (GO) in its aqueous suspension. The resultant binder-...

Electric Vehicle (EV) possesses a significant potential to provide clean energy in vehicular technology. To increase the drive cycle efficiency and the driving range of EVs, which is considered to be the key barrier for its successful commercialization, its energy storage technology needs to be improved. The power requirement of an electric vehicle cannot be satisfied by the battery alone as it...

The main challenge in designing mobile embedded systems for internet of things is to provide a solution that has the limitied power by battery lifetime, in addition to overcome frequent battery recharging or replacement. The help of solar and wind energy harvesting systems is an attractive method to increase the autonomy of mobile embedded systems for internet of things trying to make a continu...

Hierarchical VOOH hollow spheres with low crystallinity composed of nanoparticles were prepared by a facile and template-free method, which involved a precipitation of precursor microspheres in aqueous solution at room temperature and subsequent hydrothermal reaction. Quasi-solid-state symmetric and asymmetric supercapacitor (SSC and ASC) devices were fabricated using hierarchical VOOH hollow s...

To develop electrical busses for applications with a fast recharge system in stations, PVI has been testing some electrical energy components like supercapacitors and batteries with high power density. Neverthless, supercapacitors limit average autonomy between two recharge points, due to their poor energy density. On the other side cycle life of batteries are very dependent on current. To surm...

Electric vehicles have recently attracted research interest. An electric vehicle is composed of two energy sources, such as fuel cells and ultracapacitors, which are employed to provide, respectively, the steady-state and transient power demanded by the vehicle. A bidirectional DC-DC converter is needed to interface the ultracapacitor to a DC bus. The pack of ultracapacitor consists of many cel...

STATCOMs are widely used to enhance power system stability. They can exchange reactive power with the power system, but they have limited ability to exchange real power because they don’t include energy storage devices. STATCOMs coupled with energy storage devices such as batteries have been introduced to improve their ability to exchange real power. However, batteries have a limitation in thei...

Supercapacitors also known as electrochemical capacitors, that store energy via either Faradaic or non-Faradaic processes, have recently grown popularity mainly because they complement, and can even replace, conventional energy storage systems in variety of applications. Supercapacitor performance can be improved significantly by developing new nanocomposite electrodes which utilizes both the e...