Performances Of Lithium-Ion Cells Constituted Of NMC // LTO Electrodes And Ionic Liquid Or Carbonates-Based Electrolytes

摘要

Commercial lithium-ion batteries could lead to safety issues related to the use of flammable carbonates as electrolyte solvents. To provide safer cells, ionic liquids are widely studied as they possess negligible vapour pressure and reduced flammability. This paper presents a comparison between carbonates and ionic liquid-based electrolytes, comprising bis(trifluoromethanesulfonyl)imide [NTf_2] anion and imidazolium [Im] or pyrrolidinium [PYR] cations. Lithium-ion cells constituted of Li_4Ti_5O_(12) (LTO) and LiNi_(1/3)Mn_(1/3)Co_(1/3)O_2 (NMC) electrodes were assembled and cycled at 25 and 60 °C with these different electrolytes. These systems were investigated by cyclic voltammetry (CV) and electrochemical cycling. Diffusion coefficients of lithium ions were also determined by CV techniques and by liquid NMR.