Well-Wrapped Li-Rich Layered Cathodes by Reduced Graphene Oxide towards High-Performance Li-Ion Batteries.

Di Liu,Gang Wang,Xiaochuan Duan,Zeyu Wang,Xin Li,Congjie Lv,Fengying Wang

doi:10.3390/molecules24091680

Abstract

Layered lithium-rich manganese oxide (LLO) cathode materials have attracted much attention for the development of high-performance lithium-ion batteries. However, they have suffered seriously from disadvantages, such as large irreversible capacity loss during the first cycle, discharge capacity decaying, and poor rate performance. Here, a novel method was developed to coat the surface of 0.4Li2MnO3∙0.6LiNi1/3Co1/3Mn1/3O2 cathode material with reduced graphene-oxide (rGO) in order to address these drawbacks, where a surfactant was used to facilitate the well-wrapping of rGO. As a result, the modified LLO (LLO@rGO) cathode exhibits superior electrochemical performance including cycling stability and rate capability compared to the pristine LLO cathode. In particular, the LLO@rGO with a 0.5% rGO content can deliver a high discharge capacity of 166.3 mAh g−1 at a 5C rate. The novel strategy developed here can provide a vital approach to inhibit the undesired side reactions and structural deterioration of Li-rich cathode materials, and should be greatly useful for other cathode materials to improve their electrochemical performance.

Highlights

Since Sony commercialized rechargeable batteries as lithium-ion batteries in 1991, these lithium-ion batteries have revolutionized the face of consumer electronics [1,2]
Layered lithium-rich manganese oxide (LLO) cathode materials have always seriously suffered from disadvantages, such as large irreversible capacity loss during the first cycle, discharge capacity decaying, and poor rate performance [4,5,6]
We found that the reduced graphene-oxide (rGO) The coating can greatly improve the cycling and rate is shown in the

Summary

Introduction

Since Sony commercialized rechargeable batteries as lithium-ion batteries in 1991, these lithium-ion batteries have revolutionized the face of consumer electronics [1,2]. In order to solve these problems, several strategies have been developed, including surface coating [7,8,9], metal doping [10,11,12] and morphology controlling [13,14,15]. Among these modification methods, surface coating is a very effective method to improve the electrochemical properties of materials [16]

Methods

Results

Conclusion