Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems,However,the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electro...Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems,However,the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electronic devices,In this work,the zinc-ion hybrid super-capacitor with high volumetric energy density and superb cycle stability had been constructed which employing the high-density threedimensional graphene hydrogel as cathode and Zn foil used as anode in 1 mol/L ZnSO4 electrolyte.Benefiting from the abundant ion transport paths and the abundant active sites for graphene hydrogel with high density and porous structure,the zinc-ion hybrid super-capacitor exhibited an extremely high volumetric energy density of 118.42 Wh/L and a superb power density of 24.00 kW/L,as well as an excellent long cycle life(80% retention after 30,000 cycles at 10 A/g),which was superior to the volumetric energy density of the reported zinc-ion hybrid super-capacitors.This device,based on the fast ion adsorption/deso rption on the capacitor-type graphene cathode and reversible Zn^(2+) plating/stripping on the battery-type Zn anode,which will inspire the development of zinc-ion hybrid super-capacitor in miniaturized devices.展开更多
The fabrication and characterization of new type Nickel oxide/KOH/Activecarbon super-capacitor have been described. Porous nickel oxide was prepared by hydrolysis of nickelacetate and heated in air at 300 deg C. The r...The fabrication and characterization of new type Nickel oxide/KOH/Activecarbon super-capacitor have been described. Porous nickel oxide was prepared by hydrolysis of nickelacetate and heated in air at 300 deg C. The resulting nickel oxide behaved as an electrochemicalcapacitor electrode with a specific capacitance (50-70 F/g) superior to most active carbonelectrodes. This kind of nickel oxide maintained high utilization at high rate of discharge (i.e.,high power density) and had excellent cycle life more than 1000 times, while the capacitance of thecell composed of two identical nickel oxide electrodes was poor at high discharge current densityand the maximum operational voltage of this type capacitor was limited to 0.5 V. A new typesuper-capacitor was designed in which the nickel oxide and the active carbon were applied to thepositive and negative electrodes respectively. The breakdown voltage of this type super-capacitorwas improved effectively to 0.8 V and excellent characteristic of high power discharge was attainedin this way. The Nickel oxide/KOH/Active carbon super-capacitor has promising potentials in portabletelecommunications, uninterruptable power supplies and battery load leveling applications.展开更多
To improve the equivalent inertia of DC microgrids(DCMGs),a unified control is proposed for the first time for a bi-directional DC-DC converter based super-capacitor(SC)system,whereby power smoothing and SC terminal v...To improve the equivalent inertia of DC microgrids(DCMGs),a unified control is proposed for the first time for a bi-directional DC-DC converter based super-capacitor(SC)system,whereby power smoothing and SC terminal voltage regulation can be achieved in a DCMG simultaneously.The proposed control displays good plug-and-play features using only local measurements.For quantitative analysis and effective design of the critical parameter of unified control,two indices,equivalent power supporting time and inertia contributed by the unified controlled SC system,are introduced firstly.Then,with a simple but effective reduced-order model of a DCMG,analytical solutions are obtained for the two indices.In addition,a systematic design method is presented for the proposed unified control.Finally,to verify the proposed unified control,a switching model is developed for a typical DCMG in PSCAD/EMTDC,and theoretical analyses are conducted for different operating conditions.展开更多
提出了一种混合储能聚合商(hybrid energy storage aggregator,HESA)参与能量-调频市场的控制策略。首先,对于独立系统运营商(ISO)发出的调频指令信号进行VMDWVD时频域分析,重构固有模态分量(IMF)生成高频信号与低频信号,分别作为HESA...提出了一种混合储能聚合商(hybrid energy storage aggregator,HESA)参与能量-调频市场的控制策略。首先,对于独立系统运营商(ISO)发出的调频指令信号进行VMDWVD时频域分析,重构固有模态分量(IMF)生成高频信号与低频信号,分别作为HESA中功率型储能和能量型储能的输入信号。其次,构建了计及多市场价格不确定性的HESA投标与运行策略min-max-min模型,基于列和约束生成算法(C&CG)和强对偶理论对主子问题进行迭代交替求解。最后,基于实际PJM市场的价格、调频信号等数据进行了仿真,验证了HESA主体投标运营策略的有效性。展开更多
基金supported by the National Nature Science Foundations of China (No.21965019)the China Postdoctoral Science Foundation (No.2017M613248)+1 种基金the Natural Science Foundation of Gansu Province (No.1506 RJZA091)the Scientific Research Foundation of the Higher Education Institutions of Gansu Province (No.2015A-037)。
文摘Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems,However,the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electronic devices,In this work,the zinc-ion hybrid super-capacitor with high volumetric energy density and superb cycle stability had been constructed which employing the high-density threedimensional graphene hydrogel as cathode and Zn foil used as anode in 1 mol/L ZnSO4 electrolyte.Benefiting from the abundant ion transport paths and the abundant active sites for graphene hydrogel with high density and porous structure,the zinc-ion hybrid super-capacitor exhibited an extremely high volumetric energy density of 118.42 Wh/L and a superb power density of 24.00 kW/L,as well as an excellent long cycle life(80% retention after 30,000 cycles at 10 A/g),which was superior to the volumetric energy density of the reported zinc-ion hybrid super-capacitors.This device,based on the fast ion adsorption/deso rption on the capacitor-type graphene cathode and reversible Zn^(2+) plating/stripping on the battery-type Zn anode,which will inspire the development of zinc-ion hybrid super-capacitor in miniaturized devices.
基金the National Natural Science Foundation of China (No.59807001).
文摘The fabrication and characterization of new type Nickel oxide/KOH/Activecarbon super-capacitor have been described. Porous nickel oxide was prepared by hydrolysis of nickelacetate and heated in air at 300 deg C. The resulting nickel oxide behaved as an electrochemicalcapacitor electrode with a specific capacitance (50-70 F/g) superior to most active carbonelectrodes. This kind of nickel oxide maintained high utilization at high rate of discharge (i.e.,high power density) and had excellent cycle life more than 1000 times, while the capacitance of thecell composed of two identical nickel oxide electrodes was poor at high discharge current densityand the maximum operational voltage of this type capacitor was limited to 0.5 V. A new typesuper-capacitor was designed in which the nickel oxide and the active carbon were applied to thepositive and negative electrodes respectively. The breakdown voltage of this type super-capacitorwas improved effectively to 0.8 V and excellent characteristic of high power discharge was attainedin this way. The Nickel oxide/KOH/Active carbon super-capacitor has promising potentials in portabletelecommunications, uninterruptable power supplies and battery load leveling applications.
基金supported in part by the National Nature Science Foundation(No.51977142)National Key R&D Program of China(No.2020YFB1506803)Tianjin Natural Science Foundation(No.20JCQNJC00350)。
文摘To improve the equivalent inertia of DC microgrids(DCMGs),a unified control is proposed for the first time for a bi-directional DC-DC converter based super-capacitor(SC)system,whereby power smoothing and SC terminal voltage regulation can be achieved in a DCMG simultaneously.The proposed control displays good plug-and-play features using only local measurements.For quantitative analysis and effective design of the critical parameter of unified control,two indices,equivalent power supporting time and inertia contributed by the unified controlled SC system,are introduced firstly.Then,with a simple but effective reduced-order model of a DCMG,analytical solutions are obtained for the two indices.In addition,a systematic design method is presented for the proposed unified control.Finally,to verify the proposed unified control,a switching model is developed for a typical DCMG in PSCAD/EMTDC,and theoretical analyses are conducted for different operating conditions.
文摘提出了一种混合储能聚合商(hybrid energy storage aggregator,HESA)参与能量-调频市场的控制策略。首先,对于独立系统运营商(ISO)发出的调频指令信号进行VMDWVD时频域分析,重构固有模态分量(IMF)生成高频信号与低频信号,分别作为HESA中功率型储能和能量型储能的输入信号。其次,构建了计及多市场价格不确定性的HESA投标与运行策略min-max-min模型,基于列和约束生成算法(C&CG)和强对偶理论对主子问题进行迭代交替求解。最后,基于实际PJM市场的价格、调频信号等数据进行了仿真,验证了HESA主体投标运营策略的有效性。
