Chemical lithium insertion into sol–gel lamellar manganese dioxide MnO1.85·nH2O

Abstract

Chemical lithium insertion in the sol–gel manganese oxide MnO_1.85·nH₂O has been performed using n-butyllithium as a reducing agent. Open-circuit voltage (OCV) experiments, IR, XRD and thermal analysis on lithiated samples Li_xMnO_1.85·nH₂O 0 < x⩽ 0.45 show that lithium insertion into the host lattice induces a slight structural change: from x= 0.05, a relative gliding of MnO₆ layers occurs, leading to the transformation of the initial hexagonal structure into a closely related monoclinic phase. The higher the lithium content, the stronger the Li–hydrogen bond interactions which explains the contraction of the lattice observed along the c direction. The low magnitude of the structural changes is consistent with the high reversible behaviour found for this compound used as rechargeable cathodic material for lithium batteries.