Intrinsic electrochemical characteristics of one LiNi0.5Mn1.5O4 spinel particle

Abstract

A precise understanding of the intrinsic electrochemical characteristics of electrode active materials is significant for designing next-generation Li-ion batteries (LIBs). Spinel phase LiNi0.5Mn1.5O4 (LNMO) is a promising cathode material, because of its high operation voltage (~4.7V vs. Li+/Li). We demonstrate that the electrochemical characteristics of an LNMO particle electrode, without any interference additives, may be probed by the single particle measurement technique. This technique provides explicit evidence that single spherical LNMO particles with diameters of 10–20μm are reliably rechargeable, exhibit high discharge rate capability, and produce an exchange current density of ~0.2mAcm−2 for the Ni4+/Ni2+ redox couple in the depth of discharge (DOD) range of 10–40%, based on quasi-Tafel analysis. This work effectively demonstrates the efficacy of using the single particle measurement technique to evaluate the intrinsic properties of 5V class cathode materials.