Hosseini-Bab-Anari Elham, Navarro-Suárez Adriana M, Moth-Poulsen Kasper, Johansson Patrik
Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
Phys Chem Chem Phys. 2019 Aug 21;21(33):18393-18399. doi: 10.1039/c9cp03445e.
The electrolyte salt plays an important role for the overall performance and safety of lithium- and sodium-ion batteries (LIBs and SIBs, respectively). Here, two new lithium and sodium pseudo-delocalized pyridinium anion based salts were used to prepare ionic liquid (IL) based electrolytes. The Li and Na salts of the 1-methylpyridinum 2,6-dicarboxylate anion (MM26py) were synthesized and dissolved in an IL matrix (Pyr14TFSI) - hence creating mixed anion electrolytes. The obtained electrolytes are stable up to 150 and 200 °C and show ion conductivities of 2.8 and 3.2 mS cm-1 at room temperature, for the LIB and SIB electrolytes, respectively. A competitive effect between the MM26py and the TFSI anions to coordinate the alkali metal cations is observed. Finally, the electrochemical stability windows of 2.3 and 2.5 V, respectively, confirm that these electrolytes can be used practically in medium-voltage LIBs and SIBs.
电解质盐对于锂离子电池和钠离子电池（分别为LIBs和SIBs）的整体性能及安全性起着重要作用。在此，两种基于新型锂和钠伪离域吡啶鎓阴离子的盐被用于制备基于离子液体（IL）的电解质。合成了1-甲基吡啶鎓2,6-二羧酸根阴离子（MM26py）的锂盐和钠盐，并将其溶解在离子液体基质（Pyr14TFSI）中，从而制得混合阴离子电解质。所获得的电解质在高达150和200°C时稳定，对于LIB和SIB电解质，在室温下的离子电导率分别为2.8和3.2 mS cm-1。观察到MM26py和TFSI阴离子在配位碱金属阳离子方面存在竞争效应。最后，分别为2.3和2.5 V的电化学稳定窗口证实了这些电解质可实际应用于中压LIBs和SIBs。
