Nanosized CoO Loaded on Copper Foam for High-Performance, Binder-Free Lithium-Ion Batteries

Mingna Liao,Yali Zhang,Zhiwei Xu,Fengling Tang,Youpeng Li,Lingzhi Zhao,Chenghao Yang,Xin Zhou,Qiang Ru,Qilun Zhang

doi:10.3390/nano8040183

Abstract

The synthesis of nanosized CoO anodes with unique morphologies via a hydrothermal method is investigated. By adjusting the pH values of reaction solutions, nanoflakes (CoO-NFs) and nanoflowers (CoO-FLs) are successfully located on copper foam. Compared with CoO-FLs, CoO-NFs as anodes for lithium ion batteries present ameliorated lithium storage properties, such as good rate capability, excellent cycling stability, and large reversible capacity. The initial discharge capacity is 1470 mA h g−1, while the reversible capacity is maintained at 1776 m Ah g−1 after 80 cycles at a current density of 100 mA h g−1. The excellent electrochemical performance is ascribed to enough free space and enhanced conductivity, which play crucial roles in facilitating electron transport during repetitive Li+ intercalation and extraction reaction as well as buffering the volume expansion.

Highlights

Over the past few decades, lithium-ion batteries (LIBs) have been widely used as a predominant energy transformation and storage system for laptops, electric vehicles, and portable electronic products [1,2,3]
Commercial carbonaceous anodes are limited by their low capacity (~372 mA h g−1), which means they can barely meet the growing requirements for next-generation LIBs [4,5]
CoO has been extensively researched owing to its high theoretical capacities (716 mA h g−1) based on the conversion mechanism and its completely reversible electrochemical reaction as follows: CoO + 2Li+ + 2e− ↔ Li2O + Co, which is different from the reaction of lithium intercalation and de-intercalation in a carbon anode: 6C + xLi+ + xe− ↔ LixC6 [15,16,17]

Summary

Introduction

Over the past few decades, lithium-ion batteries (LIBs) have been widely used as a predominant energy transformation and storage system for laptops, electric vehicles, and portable electronic products [1,2,3]. CoO has been extensively researched owing to its high theoretical capacities (716 mA h g−1) based on the conversion mechanism and its completely reversible electrochemical reaction as follows: CoO + 2Li+ + 2e− ↔ Li2O + Co , which is different from the reaction of lithium intercalation and de-intercalation in a carbon anode: 6C + xLi+ + xe− ↔ LixC6 [15,16,17]. It has been reported that CoO nanostructures grown on various conductive substrates such as copper foil [28], nickel foam [29], Ti foil [30], and carbon cloth [31].

Results

Conclusion