Surface analysis on discharged MnO₂ cathode using XPS and SIMS techniques

Abstract

Manganese dioxide (MnO 2 ) appears to be an effective cathode material for a battery system. No studies on lithium insertion in aqueous media are known to the best of our knowledge. However, in one of our previous papers we reported that lithium could be intercalated into a MnO 2 host compound using an aqueous LiOH electrolyte; however simple chemistry suggests that it should not. It is found that a battery with LiOH electrolyte functions quite differently from the cell that uses Li 2 SO 4 . This paper describes the surface modifications that accompany the electrochemical behavior of MnO 2 during redox (discharge) processes in the lithium hydroxide and sulfate media. XPS and SIMS techniques were used to study the resultant surface of the MnO 2 cathode and the spectra reveal that the formation of an insoluble layer of Li 2 CO 3 precedes the process of reduction. SEM was used to study the microstructure of the MnO 2 cathode.

A Review of the Relationship between Gel Polymer Electrolytes and Solid Electrolyte Interfaces in Lithium Metal Batteries

“…Minakshi et al studied the application of aqueous LiOH electrolytes in lithium batteries. An aqueous rechargeable lithium battery with MnO 2 as a cathode and Zn as an anode has the advantages of low cost and environmental friendliness [105,106]. However, compared with organic electrolyte lithium batteries, there is still room for improvement in the energy density and electrochemical window of aqueous LiOH lithium batteries [107,108].…”