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Hydrogen transport in solids, applied in electrochemical devices such as fuel cells and electrolysis cells, is key to sustainable energy societies. Although using proton (H + ) conductors is an attractive choice, practical conductivity at intermediate temperatures (200-400 °C), which would be ideal for most energy and chemical conversion applications, remains a challenge. Alternatively, hydride ions (H - ), that is, monovalent anions with high polarizability, can be considered a promising charge carrier that facilitates fast ionic conduction in solids. Here, we report a K 2 NiF 4 -type Ba-Li oxyhydride with an appreciable amount of hydrogen vacancies that presents long-range order at room temperature. Increasing the temperature results in the disappearance of the vacancy ordering, triggering a high and essentially temperature-independent H - conductivity of more than 0.01 S cm -1 above 315 °C. Such a remarkable H - conducting nature at intermediate temperatures is anticipated to be important for energy and chemical conversion devices., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

In this Full Paper we show that the use of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as conducting salt in commercial lithium-ion batteries is made possible by introducing fluorinated linear carbonates as electrolyte (co)solvents. Electrolyte compositions based on LiTFSI and fluorinated carbonates were characterized regarding their ionic conductivity and electrochemical stability towards oxidation and with respect to their ability to form a protective film of aluminum fluoride on the aluminum surface. Moreover, the investigation of the electrochemical performance of standard lithium-ion anodes (graphite) and cathodes (Li[Ni1/3 Mn1/3 Co1/3 ]O2 , NMC) in half-cell configuration showed stable cycle life and good rate capability. Finally, an NMC/graphite full-cell confirmed the suitability of such electrolyte compositions for practical lithium-ion cells, thus enabling the complete replacement of LiPF6 and allowing the realization of substantially safer lithium-ion batteries., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel lithium–oxygen batteryexploiting PYR14TFSI–LiTFSI as ionic liquid-based electrolyte medium is reported.The Li/PYR14TFSI–LiTFSI/O2battery wasfully characterizedby electrochemical impedance spectroscopy, capacity-limited cycling,field emission scanning electron microscopy, high-resolution transmissionelectron microscopy, and X-ray photoelectron spectroscopy. The resultsof this extensive study demonstrate that this new Li/O2cell is characterized by a stable electrode–electrolyte interfaceand a highly reversible charge–discharge cycling behavior.Most remarkably, the charge process (oxygen oxidation reaction) ischaracterized by a very low overvoltage, enhancing the energy efficiencyto 82%, thus, addressing one of the most critical issues preventingthe practical application of lithium–oxygen batteries. [ABSTRACT FROM AUTHOR]

Abstract: The performance of full cells featuring high-voltage LiNi0.4Mn1.6O4 cathode and graphite anode with carbonate-based electrolytes, ethylene carbonate (EC) -dimethyl carbonate (DMC) with conventional LiPF6 and non-conventional Li[(C2F5)3PF3] (LiFAP) lithium salts with and without SEI-forming additives 1-fluoro ethylene carbonate (F1EC) and succinic anhydride (SA) is investigated. The results evidence the beneficial impact of EC-DMC-1M LiFAP electrolyte (LF30), with respect to EC-DMC-1M LiPF6 electrolyte (LP30), also in presence of 1.6% F1EC-2% SA additives, on charge retention over cycling and on self-discharge of full cells. After the 25 cycles of the charge capability test, the charge retention reached values up to 70% with LF30 and 87% with LF30 and additives, and fully charged cells with LF30-additives delivered 53% of the stored charge after one week in OCV. [Copyright &y& Elsevier]