Introduction of two lithiooxycarbonyl groups enhances cyclability of lithium batteries with organic cathode materials

Abstract

To increase the cyclability of lithium batteries using organic cathode materials of low molecular weights, two lithiooxycarbonyl (–CO[2]Li) groups was introduced to p- and o-quinones. The introduction of two –CO[2]Li groups does not strongly affect the redox potentials of quinones. Lithium batteries using p- and o-quinones with two –CO[2]Li groups as cathode materials exhibit excellent cyclability compared to their parent quinones. In particular, pyrene-4, 5, 9, 10-tetraone having two lithiooxycarbonyl groups (LCPYT) exhibited high energy density, high cyclability, and fast charge ability. These results indicate that introduction of two lithiooxycarbonyl groups to quinones serves as a simple and effective way to decrease the solubility of various quinones in electrolyte solutions without significant decrease in the voltage.