Investigations of Doping and Dissolution in Lithium Transition Metal Oxides Using Density Functional Theory Methods

Abstract

LiMn2O4 (LMO) has become a promising candidate to replace LiCoO2 as a cathode material in high power Li-ion batteries, due to its ease of preparation, low cost and non-toxicity. However, the performance of LiMn2O4 cathode is limited by capacity fade, particularly at high temperatures. It is believed that the capacity fade of LiMn2O4 is driven by the loss of Mn resulting from the disproportionation of surface Mn3+ with the resultant divalent Mn ions dissolving into stray moisture and electrolyte. In this work, we investigate possible candidate LMO dopants that can inhibit or reduce Mn dissolution. Several dopant-selection criteria are considered, and the electronic structure of the doped LMO will be discussed.