风能和太阳能项目增长迅猛,但是在无风和太阳落山之后的储能问题仍然是一大挑战,挑战难处主要在于成本。目前,据ACS的Chemistry of Materials杂志报道,近日,苏黎世联邦理工学院的研究人员正在开发一种使用低成本材料钠和镁的新型电池,...风能和太阳能项目增长迅猛,但是在无风和太阳落山之后的储能问题仍然是一大挑战,挑战难处主要在于成本。目前,据ACS的Chemistry of Materials杂志报道,近日,苏黎世联邦理工学院的研究人员正在开发一种使用低成本材料钠和镁的新型电池,可降低储能成本问题。研究人员创建了一种新的电池系统——钠镁混合电池,它将比锂电池具有更好的性能,而且材料也更加廉价。展开更多
近日,《经济学人》杂志发表文章重点报道了韩国光州科学技术院Lu Wu的研究工作,Lu博士和其同事们已经研发出新型石墨烯的制备方法,并且用此石墨烯能够制备出更高性能的超级电容器。《经济学人》杂志上刊登的文章报道了一些令人难以置信...近日,《经济学人》杂志发表文章重点报道了韩国光州科学技术院Lu Wu的研究工作,Lu博士和其同事们已经研发出新型石墨烯的制备方法,并且用此石墨烯能够制备出更高性能的超级电容器。《经济学人》杂志上刊登的文章报道了一些令人难以置信的声明,如韩国研究人员制备的石墨烯超级电容器的比能量比锂离子(Li—ion)电池更高,而且,发表在《Journal of Power Sciences》上的研究论文提供了一份没有广泛宣传但仍然令人印象深刻的研究成果清单。展开更多
Herein,we have presented a supercapacitor based on carbide derived carbon(CDC) electrode with natural graphite(NG) addition.The capacitor was analyzed at 22°C by cyclic voltammetry,galvanostatic charge-discharge ...Herein,we have presented a supercapacitor based on carbide derived carbon(CDC) electrode with natural graphite(NG) addition.The capacitor was analyzed at 22°C by cyclic voltammetry,galvanostatic charge-discharge and impedance techniques using a 0.5 mol/L of magnesium(II)bis(trifluoro methanesulfonyl) imide(Mg TFSI) in ethylene carbonate-propylene carbonate(EC :PC = 1 :1,v/v) as electrolyte.The results conclude that the CDC cell enhancements have been proven by the composite electrode(5%–30% NG to CDC) especially on the cell efficiency and voltage i.e.,the CDC cell around 2.5 V limit was improved.An obtainable specific capacitance,real power and energy density are 15 F g-1,1.2 k W kg-1and 15 Wh kg-1,respectively.展开更多
采用基于密度泛函理论的第一性原理平面波论调势方法计谋了Li-Si各种合金相的物理性质和电化学性能.结果表明:除了在反应过程中生成传统的固态电解持SEI膜之外形成的Li12Si7合金相也是部分导致首次不可逆容量损失的重要原因.另外,采用...采用基于密度泛函理论的第一性原理平面波论调势方法计谋了Li-Si各种合金相的物理性质和电化学性能.结果表明:除了在反应过程中生成传统的固态电解持SEI膜之外形成的Li12Si7合金相也是部分导致首次不可逆容量损失的重要原因.另外,采用射频磁控溅射制备了纯Si薄膜电极,并运用XRD、徨伏安CV、恒流充放电CC表征和测试了材料的结构和电化学性能,结果表明首次不可逆容量损失非常大,无定型结构能有交抑制体积膨胀和改善徨性能.
Abstract:
An ab initio method of the first-principles plane-wave pseudopotentials based on the density functional theory has been used to calculate the physical character and electrochemical performance of various alloy phases in Li-Si alloy. The results show that besides the growth of solid electrolyte interphase (SEI), the formation of Li12Si7 alloy phase also partly leads to the initial irreversible capacity loss. In addition, the pure silicon thin film electrode was prepared by the radio frequency (RF) magnetic sputtering on copper foil collector as anode materials. The structural and electrochemical characteristics of Li-Si alloy were examined using X-ray diffraction (XRD), cyclic voltammogram (CV) and repeatedly constant current charge/discharge (CC). The results show that the fast irreversible capacity loss is very large and amorphous structure can accommodate the large volume expansions and improve cyclic performance.展开更多
文摘风能和太阳能项目增长迅猛,但是在无风和太阳落山之后的储能问题仍然是一大挑战,挑战难处主要在于成本。目前,据ACS的Chemistry of Materials杂志报道,近日,苏黎世联邦理工学院的研究人员正在开发一种使用低成本材料钠和镁的新型电池,可降低储能成本问题。研究人员创建了一种新的电池系统——钠镁混合电池,它将比锂电池具有更好的性能,而且材料也更加廉价。
文摘近日,《经济学人》杂志发表文章重点报道了韩国光州科学技术院Lu Wu的研究工作,Lu博士和其同事们已经研发出新型石墨烯的制备方法,并且用此石墨烯能够制备出更高性能的超级电容器。《经济学人》杂志上刊登的文章报道了一些令人难以置信的声明,如韩国研究人员制备的石墨烯超级电容器的比能量比锂离子(Li—ion)电池更高,而且,发表在《Journal of Power Sciences》上的研究论文提供了一份没有广泛宣传但仍然令人印象深刻的研究成果清单。
基金RC personally thanks Marie Curie Amarout award and its financial support of this work
文摘Herein,we have presented a supercapacitor based on carbide derived carbon(CDC) electrode with natural graphite(NG) addition.The capacitor was analyzed at 22°C by cyclic voltammetry,galvanostatic charge-discharge and impedance techniques using a 0.5 mol/L of magnesium(II)bis(trifluoro methanesulfonyl) imide(Mg TFSI) in ethylene carbonate-propylene carbonate(EC :PC = 1 :1,v/v) as electrolyte.The results conclude that the CDC cell enhancements have been proven by the composite electrode(5%–30% NG to CDC) especially on the cell efficiency and voltage i.e.,the CDC cell around 2.5 V limit was improved.An obtainable specific capacitance,real power and energy density are 15 F g-1,1.2 k W kg-1and 15 Wh kg-1,respectively.
基金Acknowledgments This work was financially supported by the following funds: (1) JiangXi Provincial Department of Science and Technology (2007GZS0071) (2) Jiangxi Provincial Department of Education (G J J08347).
基金This work was financially supported by the following funds: (1) Jiangxi Provincial Department of Science and Technology (No. 2007GZS0071) (2) Jiangxi Provincial Department of Education (No. G J J08347).
文摘采用基于密度泛函理论的第一性原理平面波论调势方法计谋了Li-Si各种合金相的物理性质和电化学性能.结果表明:除了在反应过程中生成传统的固态电解持SEI膜之外形成的Li12Si7合金相也是部分导致首次不可逆容量损失的重要原因.另外,采用射频磁控溅射制备了纯Si薄膜电极,并运用XRD、徨伏安CV、恒流充放电CC表征和测试了材料的结构和电化学性能,结果表明首次不可逆容量损失非常大,无定型结构能有交抑制体积膨胀和改善徨性能.
Abstract:
An ab initio method of the first-principles plane-wave pseudopotentials based on the density functional theory has been used to calculate the physical character and electrochemical performance of various alloy phases in Li-Si alloy. The results show that besides the growth of solid electrolyte interphase (SEI), the formation of Li12Si7 alloy phase also partly leads to the initial irreversible capacity loss. In addition, the pure silicon thin film electrode was prepared by the radio frequency (RF) magnetic sputtering on copper foil collector as anode materials. The structural and electrochemical characteristics of Li-Si alloy were examined using X-ray diffraction (XRD), cyclic voltammogram (CV) and repeatedly constant current charge/discharge (CC). The results show that the fast irreversible capacity loss is very large and amorphous structure can accommodate the large volume expansions and improve cyclic performance.