Electrochemical Behavior of Solid Lithium Manganate (LiMn₂O₄) in Aqueous Neutral Electrolyte Solutions

Abstract

Lithium manganate (LiMn2O4) was synthesized by a very simple low-temperature solution combustion technique. The product was characterized for its phase formation and composition by X-ray diffraction and inductively coupled plasma spectroscopy. The electrochemical behavior of this material in aqueous neutral electrolyte solutions was investigated in an effort to find a means of making it a usable electrode material for rechargeable battery systems in aqueous electrolytes. Cyclic voltammetric and chronopotentiometric studies of solid LiMn2O4 immobilized on a paraffin-impregnated graphite electrode were carried out in various aqueous neutral electrolyte solutions. LiMn2O4 was shown to undergo reversible insertion of K+, Li+, and NH4+ ions from neutral electrolyte solutions. Energy-dispersive X-ray (EDX) detection of electrochemically treated LiMn2O4 proved the presence of the intercalated K+ ion. The intercalation of the K+ ion was partial, as is shown by the weight percent analysis of EDX detection results.