Effects of Li Content on Structure and Electrochemical Properties of Li[sub 1+x](Ni[sub 0.5]Mn[sub 0.5])[sub 1−x]O[sub 2] (0≤x≤0.15) Electrodes in Lithium Cells (1.0–4.8 V)

Layered materials have been synthesized using and coprecipitated . The materials with increased lithium content showed distinct differences in particle morphology, which is attributed to the melting of excess during calcination. The powder XRD patterns and the initial charging curves to indicated that the excess lithium resides in the transition metal layer to form -like domains in the electrode structure such that these compounds can be reformulated in a two-component composite notation as with some cation disorder between the two components. The excess lithium significantly affected the charge/discharge behaviors in the low-voltage range and the rate capability of the electrode materials, which is attributed to increasing content and decreasing disorder (i.e., Ni content in the lithium layer) in the materials.