New Naphthalene‐Based Polyimide as an Environment‐Friendly Organic Cathode Material for Lithium Batteries

Organic carbonyl electrode materials have attracted considerable attention as high‐energy density electrode materials for environment‐friendly metal‐ion batteries comprising no heavy metals. The synthesis and investigation of a new electroactive carbonyl‐based polymer compound poly(naphthalene diimide‐alt‐benzoquinone) (NDI‐BQ) derived from 1,4,5,8‐naphthalenetetracarboxylic dianhydride and 2,5‐diaminobenzoquinone are reported. The best NDI‐BQ//Li cells deliver practical capacity of 168 mAh g⁻¹, which is higher than the generally achieved capacity for the most common inorganic materials such as LiFePO₄ or LiCoO₂. Considering the fact that practical capacity represents just ≈50% of the theoretical value for NDI‐BQ, there is a considerable potential for further improvements via multiparametric optimization of the cathode composition, morphology, and deposition technology.