Fabrication of Cathode Materials Based on Limn2o4/Cnt and Lini0.5mn1.5o4/Cnt Nanocomposites for Lithium – Ion Batteries Application

Thang Van Le,My Loan Phung Le,Man Van Tran,Ha Tran Nguyen,Anh Tuan Luu,Nguyet Minh Thi Nguyen

doi:10.1590/1516-1439.016415

Abstract

Carbon nanotubes (CNTs) are a promising candidate material for use in lithium batteries due to 1D tubular structure, high electrical, thermal conductivities, and extremely large surface area. In this work, the MWCNTs were purified by dispersion in a mixture of HNO3 and H2SO4acids. The oxidized-MWCNTs were used as conducting addition to prepare a nanocomposites as high performance cathode material for Li-ion batteries (LIBs). The spinel cathode materials of LiMn2O4 (LMO), doped spinel LiNi0.5Mn1.5O4 (LNMO) were synthesized and characterized via X-rays diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical properties of nanocomposites based on LMO/CNTs and LMNO/CNTs were investigated by cyclic voltammetry (CV) as well as electrochemical impedance spectroscopy (EIS). The EIS measurement indicated that the LMO (LNMO)/CNTs nanocomposites showed lower charge transfer resistance (Rct) than that of LMO(LNMO)/ Vulcan carbon materials. In addition, the studied nanocomposites cathodes gave a specific capacity of 145 Ah.kg–1 and 120 Ah.kg–1 for LMO/CNTs (10 wt%) and LNMO/CNTs (10 wt%), respectively, measured at a charge/discharge rate of 0.1C.

Highlights

The demand of higher energy density and higher power capacity of lithium (Li)-ion secondary batteries has led to the search for electrode materials whose capacities and performance are better than those available today[1,2,3,4,5,6,7,8]
We investigated the impact of Carbon nanotubes (CNTs) contents (2-10 wt%) in their nanocomposites to electrochemical properties of cathode material in Li-ion batteries (LIBs) application
The transmission electron microscopy (TEM) images of purified CNTs (Figure 3b) are much clearer comparing with the as-prepared one (Figure 3a). These results suggest that the CNTs were successfully purified using the acid treatment process

Summary

Introduction

The demand of higher energy density and higher power capacity of lithium (Li)-ion secondary batteries has led to the search for electrode materials whose capacities and performance are better than those available today[1,2,3,4,5,6,7,8]. A typical LIB includes an anode made from graphite, and a positive electrode (cathode) made from LiCoO2 and a Li-ion conducting electrolyte. Compared to traditional rechargeable batteries such as lead acid and Ni-Cd batteries, rechargeable LIBs provide many advantages including high voltage, high energy-to-weight ratio, i.e. high energy density, long cyclic life, no memory effect and slow loss of charge[1,2,3]. For these advantages, LIBs are currently the most popular battery type of powering portable electronic devices. LIBs have shown remarkably commercial success, the electrodes and their component materials are still the target of interesting research for enhancement of electrochemical

Methods

Results

Conclusion