Search results for "Capacitor"

PVA Hydrogel Electrolyte and Porous Polyisoprene Carbon Nanostructure Composite Based Pressure Sensitive Supercapacitor

2019

Special gratitude is in order to Raimonds Orlovs for temperature dependent resistance measurements. Financial support of project 1.1.1.1/16/A/013, “Hybrid energy harvesting systems” is greatly appreciated.

Bis(2,2'-biphenoxy)borates for electrochemical double-layer capacitor electrolytes.

2010

Fluorine makes the difference! Bis(2,2'-biphenoxy)borates decorated with fluorine substituents have been synthesized and studied in supercapacitor test cells (see scheme). A clear trend towards higher electrochemical stability with the increase of the fluorine content has been observed. For a maximum performance, only two fluorine substituents per benzene moiety are required.

Electronically conducting polymers and activated carbon: Electrode materials in supercapacitor technology

1996

Supercapacitor diagnosis using an Extended Kalman Filtering approach

2016

This paper deals with the model-based analysis of a Supercapacitor for diagnostic purposes. A two legs nonlinear physical model is assumed for the Supercapacitor and the corresponding second-order nonlinear state-space mathematical model is obtained. Then, an Extended Kalman Filter is tuned so that the estimated outputs reproduce the voltages at the equivalent capacitance terminals; they give information on the state of health of the supercapacitor but are not directly measurable. In particular, an optimization problem is firstly formulated, involving the experimental input-output data and those given by the Extended Kalman Filter.

A fuel cell-based hybrid power supply for portable electronics devices

2008

A fuel cell - supercapacitor hybrid power supply for portable applications is designed. To ensure system level simulation, each component is accurately modeled and simulation results are reported. A Digital Still Camera is selected as specific load device, although the choice of a specific application does not influence the proposed control technique performances but only dictates the power supply specifications. The fuel cell and the power management system are modeled in PSIM. © 2008 IEEE.

A DFT Study of the [3+2] Cycloadditions of RCNO (R = H, Me and F) With Carbon Flatland Mimicking Graphene

2012

Graphene is the latest allotrope of carbon to be under the spotlight ever since its discovery by Novoselov and coworkers in 2004. Owing to its fascinating structural, electrical, optical, mechanical and thermal properties, graphene can be regarded as as a rapidly rising star in various fields such as supercapacitors, biosensors and batteries. The organic chemistry of graphene has stimulated a great deal of research and is gaining considerable attention. Among the various experimental studies which have been carried out on graphene, it is found that [3+2] cycloadditions (32CA) can also be achieved on graphene sheets and the resulting functionalized graphenes are dispersible in polar organic …

Nanoporous Gold‐Based Materials for Electrochemical Energy Storage and Conversion

2021

Highly Porous Wood Based Carbon Materials for Supercapacitors

2015

Wood based activated carbons synthesized by two-stage thermocatalytical synthesis with NaOH activator were studied and used as supercapacitor electrodes (sulphuric acid electrolyte). Porous structure and electrochemical properties of carbons vs synthesis conditions were assessed. It was found that there are correlations between carbons synthesis variables, their porosity and supercapacitors functional characteristics. At the temperature 600 o C and activator/precursor ratio 1.25 porosity decreased, however energy capacitance of supercapacitor increased calculating on elementary cell mass.

Direct Metal‐Free Chemical Vapor Deposition of Graphene Films on Insulating Substrates for Micro‐Supercapacitors with High Volumetric Capacitance

2019

Direct, metal‐free synthesis of graphene films on insulating substrates in a controlled manner is of great importance for applications in (opto)electronic and energy storage devices. Graphene films are fabricated on fused silica substrates without metal catalyst via chemical vapor deposition (CVD), using propionic acid as a carbon source. Film‐thickness is readily adjustable between 5 and 45 nm by changing the deposition time and flow rate of the precursor, displaying sheet resistance in the range of 0.27–1.86 kΩ□−1. The resulting graphene films are directly integrated into micro‐supercapacitors without film transfer or liquid‐phase processing, and demonstrate ultrahigh operation rates up t…

Research frontiers in energy-related materials and applications for 2020-2030

2020

Abstract: This article delineates the state of the art for several materials used in the harvest, conversion, and storage of energy, and analyzes the challenges to be overcome in the decade ahead for them to reach the market and benefit society. The materials covered have had a special interest in recent years and include perovskites, materials for batteries and supercapacitors, graphene, and materials for hydrogen production and storage. Looking at the common challenges for these different systems, scientists in basic research should carefully consider commercial requirements when designing new materials. These include cost and ease of synthesis, abundance of precursors, recyclability of s…