大容量碳纳米管极板双电层电容器的研制

碳纳米管具有良好的导电性和合适的孔径分布以及较高的比表面积。选用聚四氟乙烯(PTFE)作为碳纳米管极板的粘结剂,网络结构的泡沫镍作为集流体,在有机电解质溶液中,通过直流充放电、恒功率充放电、循环伏安特性和自放电测试等实验,显示了本实验室制备的碳纳米管材料组装的双电层电容器具有良好的电化学性能。电容器中碳纳米管比电容量达74.1 F/g,比能量达16.1 Wh/kg,在自放电特性测试过程中,电容器漏电流稳定在2 mA左右。     

20伏高电压型碳纳米管超级电容器的研制

通过催化裂解法制备了碳纳米管并进一步制备了碳纳米管膜片式电极.基于该种材料的超级电容器电极比容量达到42F/g并表现出良好的大电流放电特性.本文采用多种研究方法对基于该种材料的双电层电容器的电化学特性进行了详细的研究.本文还开发了全新的超级电容器组装工艺,采用该工艺组装的碳纳米管超级电容器工作电压可以达到20V并具有良好的容量特性和阻抗特性.     

电化学双电层电容器的研制

通过催化裂解法制备了碳纳米管并进一步制备了碳纳米管薄膜电极。基于该种材料的超电容器电极比容量达到36 F/g并表现出良好的功率特性。本文采用多种研究方法对基于该种材料的双电层电容器进行了详细的研究。     

碳纳米管/氧化镍复合电极超大容量离子电容器

碳纳米管作为一种新型碳材料,具有质轻,高的有效比表面积和优良的导电性,是制备双电层电容器较为理想的电极材料。本文实验用硝酸回流处理碳纳米管,对其表面改性,通过sol-gel法在改性后的碳纳米管上沉积Ni(OH)2,经灼烧得到碳纳米管/氧化镍复合材料,制成电极装配成电容器单元。该电容器具有双电层电容和赝电容特性,其比电容量为160 F/g,频率响应特性较活性炭电极电容器有所提高,是一种极具发展潜力的储能器件。     

碳纳米管作为超大容量离子电容器电极的研究

本文采用碳纳米管作为超大容量离子电容器的电极材料,研究了硝酸改性处理、粘结剂对电极的电容器性能的影响,探讨了其电容的形成机理.当用硝酸改性处理的碳纳米管作电极,用30%(wt)的H₂SO₄作电解质溶液时,所得超大容量离子电容器不仅能形成双电层电容,也能形成赝电容,从而得到了69F/g的比电容;同时碳纳米管电极超大容量离子电容器具有良好的频率响应特性.     

双电层电容器及其应用

双电层电容器是具有电池和电容双重特性的新型电子元件,主要用于存储器备用电源、停机及关机备用电源、瞬间断电备用电源以及汽车能源再生系统。文中介绍了双电层电容器的设计原理以及它和电池及铝电解电容器的比较,并以哈尔滨大容电子有限公司生产的三种系列双电层电容器为例,对该产品及其应用作了介绍,最后给出了使用双电层电容器的注意事项。     

双电层电容器的技术性能及其测量

本文概述了双电层电容器的主要技术性能。列出了无极性卷绕式双电层电容器和无极性电池式双电层电容器的性能指标。详细介绍了双电层电容器的静电容量、内阻(或ESR)和漏电流的测量方法。     

锂离子电容器的市场前景及发展趋势

锂离子电容器是新型的储能电源,它是双电层电容器（超级电容器）的衍生品,与双电层电容器相比,在许多性能上具有无可比拟的优点。文中简要介绍了锂离子电容器的结构和工作原理．性能,着重给出了它的应羽．市场前景和发展趋势,     

锂离子电容器市场走势

锂离子电容器（LIC）可以说是锂离子充电电池（LIB）和双电层电容器（EDLC）的混合电容器,正极采用活性碳,负极采用石墨等材料。它比锂离子充电电池稳定,又超越了双电层电容器的电气性能,热致击穿及老化少,自放电也很少。锂离子电容器的特点是,有与双电层电容器EDLC相同的充电速度,而能量密度却高于EDLC。     

超级电容

超级电容属于双电层电容器,它是世界上已投入量产的双电层电容器中容量最大的一种,其基本原理和其它种类的双电层电容器一样,都是利用活性炭多孔电极和电解质组成的双电层结构获得超大的容量。由于其容量很大,对外表现和电池相同,因此也有称作“电容电池”。     

活性炭前处理对双电层电容器性能的影响

制备了沥青焦基活性炭双电层电容器用电极材料,将其分别经水洗、酸洗以及超音速气流粉碎处理。在1 mol/L(C2H5)4NBF4/碳酸丙烯酯电解液体系中进行电化学测试,对比评价了各活性炭前处理方法对电容器电化学性能的影响。结果表明,酸洗后活性炭电极比电容提高7%达到163 F/g,高功率放电性能明显改善,当电流密度由70 mA/g增加到1 A/g时,其电极比电容保持率为88%;活性炭进行超细粉碎后不利于电化学性能的提高。     

微波加热法制备电极材料活性炭

以煤为原料,KOH为活化剂,采用微波辐射加热法和电阻炉加热法制备出双电层电容器用活性炭。对比研究了两种工艺下KOH用量、活化时间对活性炭比电容量的影响,考察了活性炭双电层电容器的充放电特性。结果显示:微波活化时,ζ(KOH∶煤)为3∶1,起电弧时间5min,比电容为283.67F/g;电阻炉活化时,ζ(KOH∶煤)为4∶1,保温时间为1h,比电容为235.55F/g。经过100次循环充放电后,微波法和电阻炉法所得的活性炭的比电容分别保持在98.10%和91.04%。     

双电层电容器高比表面积活性炭的研究

以石油焦为原料,KOH和NaOH为活化剂制取双电层电容器用高比表面积活性炭电极材料。考察了活化剂的种类及其与石油焦配比对活性炭比电容的影响,并对KOH和NaOH的混和物在活化过程中金属K和Na的协同作用进行了初步探讨。研究结果表明控制适宜的活化工艺条件可制得比电容高达52.60 F/g的高比表面积活性炭,用它组装成的双电层电容器具有良好的充放电性能。     

Electrochemical Double-Layer Capacitors Using Carbon Nanotube Electrode Structures

The structure and behavior of the electrical double-layer capacitor (EDLC) are described. The use of activated carbon electrodes is discussed and the limitations on voltage and accessible surface area are presented. Metrics for evaluating EDLC performance are defined and previously reported results of experimental carbon nanotube (CNT) electrodes are tabulated. New experimental results of electrodes constructed of vertically aligned CNTs grown on a conducting substrate are presented. By extrapolating prior and new experimental data the energy density of CNT-based EDLCs is shown to be potentially up to seven times that of commercial activated carbon-based EDLCs.      

Gel Electrolyte Derived from Poly(ethylene glycol) Blending Poly(acrylonitrile) Applicable to Roll‐to‐Roll Assembly of Electric Double Layer Capacitors

The synthesis of a gelled polymer electrolyte (GPE) using poly(ethylene glycol) blending poly(acrylonitrile) (i.e., PAN‐b‐PEG‐b‐PAN) as a host, dimethyl formamide (DMF) as a plasticizer and LiClO₄ as an electrolytic salt for electric double layer capacitors (EDLCs) is reported. The PAN‐b‐PEG‐b‐PAN copolymer in the GPE has a linear configuration for high ionic conductivity and excellent compatibility with carbon electrodes. When assembling the GPE in a carbon‐based symmetric EDLC, the copolymer network facilitates ion motion by reducing the equivalent series resistance and Warburg resistance of the capacitor. This symmetric cell has a capacitance value of 101 F g^?1 at 0.125 A g^?1 and can deliver an energy level of 11.5 Wh kg^?1 at a high power of 10 000 W kg^?1 over a voltage window of 2.1 V. This cell shows superior stability, with little decay of specific capacitance after 30 000 galvanostatic charge‐discharge cycles. The distinctive merit of the GPE film is its adjustable mechanical integrity, which makes the roll‐to‐roll assembly of GPE‐based EDLCs readily scalable to industrial levels.     

Polypyrrole‐Derived Activated Carbons for High‐Performance Electrical Double‐Layer Capacitors with Ionic Liquid Electrolyte

As electrical energy storage and delivery devices, carbon‐based electrical double‐layer capacitors (EDLCs) have attracted much attention for advancing the energy‐efficient economy. Conventional methods for activated carbon (AC) synthesis offer limited control of their surface area and porosity, which results in a typical specific capacitance of 70–120 F g^?1 in commercial EDLCs based on organic electrolytes and ionic liquids (ILs). Additionally, typical ACs produced from natural precursors suffer from the significant variation of their properties, which is detrimental for EDLC use in automotive applications. A novel method for AC synthesis for EDLCs is proposed. This method is based on direct activation of synthetic polymers. The proposed procedure allowed us to produce ACs with ultrahigh specific surface area of up to 3432 m² g^?1 and volume of 0.5–4 nm pores up to 2.39 cm³ g^?1. The application of the produced carbons in EDLCs based on IL electrolyte showed specific capacitance approaching 300 F g^?1, which is unprecedented for carbon materials, and 5–8% performance improvement after 10 000 charge–discharge cycles at the very high current density of 10 A g^?1. The remarkable characteristics of the produced materials and the capability of the fabricated EDLCs to operate safely in a wide electrochemical window at elevated temperatures, suggest that the proposed synthesis route offers excellent potential for large‐scale material production for EDLC use in electric vehicles and industrial applications.     

Graphite Oxide as an Olefin Polymerization Carbocatalyst: Applications in Electrochemical Double Layer Capacitors

Graphite oxide (GO) is shown to be an efficient heterogeneous catalyst for the polymerization of various olefin monomers, including n‐butyl vinyl ether, N‐vinylcarbazole, styrene, and sodium 4‐styrenesulfonate. The GO‐catalyzed polymerization of n‐butyl vinyl ether (0.1–5.0 wt% GO relative to monomer) proceeds rapidly under solvent‐free conditions and affords polymers with moderate number average molecular weights and broad polydispersities. Analysis of the carbon recovered at the conclusion of the polymerization reactions reveals that the material's catalytic activity is retained and multiple polymerization cycles can be performed without regenerating the catalyst. GO also catalyzes the polymerization of N‐vinylcarbazole and styrene, although only low molecular weight polymers are obtained. Sodium 4‐styrenesulfonate polymerizes in the presence of GO to afford poly(sodium 4‐styrenesulfonate) (PSS) composites. After thermal treatment, the composites can be fabricated into electrodes for use in electrochemical double layer capacitors (EDLCs). The devices display high specific capacitances (25–120 F g^?1) and low equivalent series resistances (14–27 Ω).     

Voltage Balancing of a 320-V, 12-F Electric Double-Layer Capacitor Bank Combined With a 10-kW Bidirectional Isolated DC--DC Converter

Electric double-layer capacitors (EDLCs) have attributes that feature high power density, quick charge/discharge time, long life cycle, and environmental friendliness. These attributes accord for increased appeal in employing the EDLCs as energy-storage devices in renewable energy systems, industrial applications, and hybrid electric vehicles as compared to other mature static energy-storage devices. This paper describes the construction of a 320-V, 12-F EDLC energy-storage bank connected to a bidirectional isolated dc--dc converter. Two types of EDLC bank configurations are considered with emphasis on their voltage-balancing circuits. Subsequently, this paper proposes a voltage-balancing circuit based on a center-tapped transformer, and includes its experimental verifications. It also discusses the charge--discharge and self-starting operation of the EDLC energy-storage system. During the charge--discharge operation, a low ripple current flowing in the EDLC bank is observed, leading to a theoretical analysis. The EDLC bank is also successfully charged to its rated voltage without any external dc charging circuit.