Lithium rechargeable batteries composed of octacyanophthalocyaninatoiron and its polymer complex as cathode

Highly pure octacyanophthalocyaninatoiron complex ( FePcOC ) was synthesized by the reaction between tetracyanobenzene and iron(II) acetate in sulfolane. The complex was further converted into a coordination polymer by the reaction with tetrazine as an axial μ-bridge ligand. The charge/discharge characteristics of lithium cells with an FePcOC cathode were studied. The capacity and the energy density based on the quantity of cathode active material were ca 105 mAh g-1 and 210 Wh kg-1 respectively. Better results were obtained when the cathode material was replaced by the coordination polymer. It was found that the FePcOC and corresponding polymer complex are promising candidates as an active cathode material for lithium secondary batteries.