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Information × Registration Number 0217U003432, 0114U006100 , R & D reports Title Concept of prognozing optimal composition of electrolyte systems on the base of salt-solvates and ionic liquids for lithium-ion batteries of new generation popup.stage_title Head Kyryllov Sviatoslav Oleksandrovych, Registration Date 11-04-2017 Organization Science and Engineering Center "Tekhnoelectrokhim" of National Academy of Sciences of Ukraine popup.description2 The object of the study is the effect of solvation and ion association on the physico-chemical properties of electrolyte systems containing a lithium salt, an ionic liquid and one or two aprotic solvents. The aim of the work is to establish the regularities of solvation and association in systems containing a lithium salt, an ionic liquid and one or two aprotic solvents, in the concentration range from dilute solutions to salt-solvates and further to salt solutions in salt-solvates, and the development of a scientific concept for Predictions of the optimal properties of electrolyte systems for lithium-ion batteries of a new generation. Based on the analysis of Raman spectra (Raman spectra), it was found that in all the lithium salt-aprotic solvent systems, the average cation solvation numbers are constant and close to two. Average solvation numbers of anions decrease with increasing salt content and become two in concentrated solutions. It has been established that solvated ions and ion pairs of all types are present in solutions of lithium salts in dimethylsulfoxide (DMSO). For LiClO4-propylene carbonate (PC) and LiClO4-dimethyl carbonate (DMC) systems, it was found that solvated ions are absent in them, and conductivity is provided by solvent separated ion pairs (SSIP).In lithium salt-binary solvent systems, the presence of competitive solvation processes is shown, in particular, in a mixture of LiCF3SO3-acrylonitrile (ACN) -DMSO dimethyl sulfoxide, solvates predominantly cations and anions. In this case, ACN is prone to the formation of contact ion pairs (CIP), and DMSO - to the dominance of free anion. In the LiClO4-PC-DMC system, on the contrary, both solvents equally solvate cations and DMC preferentially solvate anions. In addition, the SSIP is quantified in the system. An investigation of the Raman spectra of lithium salt solutions in an ionic liquid-aprotic solvent mixture indicates the predominant interaction between bis (trifluoromethanesulfonyl) imide anion and lithium cations. The results of the conducted studies indicate that in solutions formed by mixed solvents whose molecules do not interact, the interactions of ions with each other and with solvent molecules remain the same as in individual solvents, and the properties of the solutions do not change. In solutions formed by mixed solvents, the molecules of which interact, there are significant changes in the interactions between the particles, which leads to significant changes in the properties. Product Description popup.authors Войтенко Олена Юріївна Горобець Марнарита Ігорівна Орел Володимир Павлович popup.nrat_date 2020-04-02 Close