Lithium Insertion / De-Insertion Properties of π-Extended Naphthyl-Based Dicarboxylate Electrode Synthesized by Freeze-Drying

Abstract

Dilithium 2,6-naphthalene di-carboxylate has been synthesized starting from the acid and lithium hydroxide using a freeze drying process which gives rise to superior electrochemical performances. This negative electrode material reacts reversibly with Li+ at a redox potential of ca. 0.88 V, and exhibits not only a total gravimetric of ca. 200 mAh.g−1 but also shows high rate capability. The improved cyclability of the electrode at high rate stems from the π-extension of the core unit separating the two redox active carboxylate groups. Such a finding should serve as an impetus to design dicarboxylate-based molecules based on core units having extended aromatic character for better electronic transport.