A New Class of Electrochemically and Thermally Stable Lithium Salts for Lithium Battery Electrolytes: III. Synthesis and Properties of Some Lithium Organoborates

Synthesis, analysis, and purification of new lithium salts for lithium batteries, lithium bis[tetrafluoro‐1,2‐benzenediolato(2‐)‐O,O']borate and lithium bis[2,3‐naphthalenediolato(2‐)‐O,O']borate are described, and the results of electrochemical studies of these salts and of lithium bis[3‐fluoro‐1,2‐benzenediolato(2‐)‐O,O']borate, in propylene carbonate are reported. The effect of the electron‐withdrawing substituent fluorine results in an increase of the electrochemical window by 0.1 V/fluorine per one chelate ligand. The slope, which can be calculated from the linear correlation of the highest occupied molecular orbital energies with anodic oxidation potentials is −3.0 eV/V, a value equal to that known for aryl borates and fluoroaryl borates.