The Experts below are selected from a list of 9 Experts worldwide ranked by ideXlab platform

Ning Pan - One of the best experts on this subject based on the ideXlab platform.

  • Supercapacitors Performance evaluation
    Advanced Energy Materials, 2014
    Co-Authors: Sanliang Zhang, Ning Pan
    Abstract:

    The Performance of a supercapacitor can be characterized by a series of key parameters, including the cell capacitance, operating voltage, equivalent series resistance, power density, energy density, and time constant. To accurately measure these parameters, a variety of methods have been proposed and are used in academia and industry. As a result, some confusion has been caused due to the inconsistencies between different evaluation methods and practices. Such confusion hinders effective communication of new research findings, and creates a hurdle in transferring novel supercapacitor technologies from research labs to commercial applications. Based on public sources, this article is an attempt to inventory, critique and hopefully streamline the commonly used instruments, key Performance metrics, calculation methods, and major affecting factors for supercapacitor Performance evaluation. Thereafter the primary sources of inconsistencies are identified and possible solutions are suggested, with emphasis on device Performance vs. material properties and the rate dependency of Supercapacitors. We hope, by using reliable, intrinsic, and comparable parameters produced, the existing inconsistencies and confusion can be largely eliminated so as to facilitate further progress in the field.

Sanliang Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Supercapacitors Performance evaluation
    Advanced Energy Materials, 2014
    Co-Authors: Sanliang Zhang, Ning Pan
    Abstract:

    The Performance of a supercapacitor can be characterized by a series of key parameters, including the cell capacitance, operating voltage, equivalent series resistance, power density, energy density, and time constant. To accurately measure these parameters, a variety of methods have been proposed and are used in academia and industry. As a result, some confusion has been caused due to the inconsistencies between different evaluation methods and practices. Such confusion hinders effective communication of new research findings, and creates a hurdle in transferring novel supercapacitor technologies from research labs to commercial applications. Based on public sources, this article is an attempt to inventory, critique and hopefully streamline the commonly used instruments, key Performance metrics, calculation methods, and major affecting factors for supercapacitor Performance evaluation. Thereafter the primary sources of inconsistencies are identified and possible solutions are suggested, with emphasis on device Performance vs. material properties and the rate dependency of Supercapacitors. We hope, by using reliable, intrinsic, and comparable parameters produced, the existing inconsistencies and confusion can be largely eliminated so as to facilitate further progress in the field.

Francesca Soavi - One of the best experts on this subject based on the ideXlab platform.

  • conducting polymers as electrode materials in Supercapacitors
    Solid State Ionics, 2002
    Co-Authors: Marina Mastragostino, Catia Arbizzani, Francesca Soavi
    Abstract:

    Abstract This paper summarizes the Performance data of conventional and especially designed thiophene-based conducting polymers for use as positive and negative electrodes in n/p type Supercapacitors. Performance data of polymer composite electrodes are also compared with those of high surface area carbon-based composite electrodes. On the basis of capacity, capacitance and electrode charging resistance data, we selected the best electrode materials, and assembled and tested galvanostatic charge–discharge cycles n/p type pMeT-based Supercapacitors and hybrid Supercapacitors with pMeT as positive electrode active material and activated carbon as negative. The results of this investigation demonstrate that a conventional polymer such as pMeT can be successfully used in the supercapacitor technology when a hybrid configuration is realized; its use is, indeed, a great advantage because the hybrid supercapacitor outperforms the double-layer carbon Supercapacitors presently on the market in terms of specific energy and power.

Marina Mastragostino - One of the best experts on this subject based on the ideXlab platform.

  • conducting polymers as electrode materials in Supercapacitors
    Solid State Ionics, 2002
    Co-Authors: Marina Mastragostino, Catia Arbizzani, Francesca Soavi
    Abstract:

    Abstract This paper summarizes the Performance data of conventional and especially designed thiophene-based conducting polymers for use as positive and negative electrodes in n/p type Supercapacitors. Performance data of polymer composite electrodes are also compared with those of high surface area carbon-based composite electrodes. On the basis of capacity, capacitance and electrode charging resistance data, we selected the best electrode materials, and assembled and tested galvanostatic charge–discharge cycles n/p type pMeT-based Supercapacitors and hybrid Supercapacitors with pMeT as positive electrode active material and activated carbon as negative. The results of this investigation demonstrate that a conventional polymer such as pMeT can be successfully used in the supercapacitor technology when a hybrid configuration is realized; its use is, indeed, a great advantage because the hybrid supercapacitor outperforms the double-layer carbon Supercapacitors presently on the market in terms of specific energy and power.

Cao Wenxin - One of the best experts on this subject based on the ideXlab platform.

  • BIOMASS-DERIVED ACTIVATED CARBONS FOR ELECTRICAL DOUBLE LAYER Supercapacitors: Performance AND STRESS EFFECT
    UKnowledge, 2019
    Co-Authors: Cao Wenxin
    Abstract:

    The vigorous development of human civilization has significantly increased the energy consumption in recent years. There is a great need to use renewable energy sources to substitute the depleting traditional fossil fuels, such as crude oil, natural gas and coal. The development of low-cost and high-Performance energy storage devices (ESDs) and systems have drawn great attention due to their feasibility as backup power supply and their applications in portable electronics and electric vehicles. Supercapacitors are among the most important ESDs because of their long charging-discharging cycle life, high power capability and a large operating temperature range. In this thesis, high-Performance activated carbons (ACs)-based SCs have been synthesized from two biomass materials in both “bottom-up” and “top-down” patterns, including high fructose corn syrup and soybean residues, which are economic and environmental friendly. Firstly, a hydrothermal carbonization (HTC) - physical activation method is presented to synthesize activated carbons from high fructose corn syrup (HFCS). The effect of the activation time on the geometrical and porous characteristics of the ACs is investigated. The electrochemical Performance of the supercapacitor cells made from AC treated at 850ºC for 4 hours are found as the best with a specific capacitance of 168 F/g at 0.2 A/g in 6 M KOH aqueous system. Secondly, a two-step HTC process followed by a physical activation to prepare activated carbons from soybean residue is presented. The effect of activation temperature on geometrical and porous characteristics of the ACs is studied. The ACs activated at 850ºC are found partly crystallized and exhibit a specific capacitance of 227 F/g at 2 mV/s. To understand the effect of mechanical deformation of the electrode materials on the electrochemical Performance of electrical double-layer Supercapacitors, a series of compression tests of HFCS-based ACs are further conducted in both dry and wet conditions. The nominal stiffness of the compressed ACs is calculated from the unloading curves. For both dry and wet disks the stiffness get increased with increased compression load, where the wet ones get higher stiffness than that of the dry ones. A simple model of porous materials is used to explain the increase in the stiffness of a compressed disk with the increase of pressure. Lastly, the effect of mechanical deformation on the electrochemical impedance of HFCS-based ACs is studied. When increasing the mechanical pressure from 4 to 81.5 KPa, the system resistance shows a relatively stable trend around 1 ohm, while the charge transfer resistance shows a dramatic dependence on mechanical pressure decreasing from 420 ohms to 1.5 ohms