Characterization of LiNi0.5Mn1.5O4 spinel electrode in the presence of 1,3,5-trihydroxybenzene as additive

Abstract

The effect of adding 1,3,5-trihydroxybenzene (THB) to the electrolyte [1.0 M LiPF₆ in ethylene carbonate (EC), diethyl carbonate (DEC) and dimethyl carbonate (DMC) (1 : 1 : 1)] on the performance and nature of the surface species on a LiNi_0.5Mn_1.5O₄ cathode in a lithium battery was investigated. The THB additive (0.1 wt%) improved the capacity retention during cycling between 3.5 and 5.0 V (vs. Li⁺/Li) at room temperature. Surface analysis of LiNi_0.5Mn_1.5O₄ before and after cycling by ex situ X-ray photoelectron spectroscopy revealed that THB inhibited electrolyte decomposition on the cathode surface. The improved cyclability of the LiNi_0.5Mn_1.5O₄ cathode is attributed to better stability of the electrode/electrolyte interface, presumably due to the presence of a THB-derived film.