Effect of SiO2 addition on the performance of high voltage spinel LiNi0.5Mn1.5O4 as a cathode material for li-ion batteries

Abstract

Li-ion batteries offers a clean, efficient and sustainable technology for energy storage. They have become the key components of modern portable electronics. Li-ion battery system provide many advantages over traditional battery systems including higher efficiency, energy density, power density, safety and lighter in weight. On the other hand there are certain limitation associated with them which limit their use such as (1) worse performance at elevated temperatures, (2) they are expensive to produce, (3) aging is required, and (4) limitation in the choice for electrode materials. The energy density of the battery system the product of its potential and capacity, and is mainly governed by the potential and capacity of cathode material. Therefore the cathode materials are one of the limiting factors in the battery performance. To develop high performance Li-ion batteries, new cathode materials with higher voltage and higher capacities must be developed in order to get higher energy density batteries. LiNi0.5Mn1.5O4 is one of the potential high voltage cathode material due to flat voltage plateau at around 4.7V and moderate capacity of around 147mAh g-1. But high voltage spinel LNMO shows worse performance at elevated temperature.Here the ordered and disordered LiNi0.5Mn1.5O4 was synthesized using sol-gel combined solid state synthesis technique for use as a high power cathode in rechargeable Li-ion batteries. The micron sized disordered LiNi0.5Mn1.5O4 showed better electrochemical performance especially at higher C-rates mainly due the presence of Mn3+. The effect of SiO2 addition in disordered LiNi0.5Mn1.5O4 was also studied. The results show that the SiO2 addition has positive effect on the electrochemical performance of LNMO. SiO2 added LNMO show better rate capability performance as well as better elevated temperature (55℃) cycleability as compared to standard LNMO. Amongst all, 1wt. % SiO2-LNMO gave the best electrochemical performance with discharge capa...