Reinforcing Germanium Electrode with Polymer Matrix Decoration for Long Cycle Life Rechargeable Lithium Ion Batteries

authored by

Xiaolei Sun, Xueyi Lu, Shaozhuan Huang, Lixia Xi, Lixang Liu, Bo Liu, Qunhong Weng, Lin Zhang, Oliver G. Schmidt

Abstract

Germanium is a promising anode material for lithium ion batteries because of its high theoretical specific capacity and low operation voltage. However, a significant challenge in using Ge-based anodes is the large volume variation during cycling that causes pulverization and capacity fade. Despite intense studies in the past decade, unsatisfactory cycling stability of the Ge-based electrodes still impedes their widespread applications. In this study, we demonstrate a high-performance electrode through the synergistic combination of a high-capacity Ge film grown on a three-dimensional current collector and an in situ formed poly(vinylidene fluoride)-hexafluoropropene/SiO

₂ protective layer. Specifically, the polymer matrix is in continuous contact with the surface of the Ge shell, which provides improved mechanical and ionic transport properties. As a highlight, we present impressive cycling stability over 3000 cycles at 1 C rate with a capacity retention as high as 95.7%. Furthermore, the LiCoO

₂-Ge full battery operates at an average voltage of 3.3 V at 0.5 C and maintains good electrochemical performance, suggesting great potential for applications in energy storage and conversion devices.

Organisation(s)

Institute of Solid State Physics

Type

Article

Journal

ACS Applied Materials & Interfaces

Volume

Pages

38556-38566

No. of pages

ISSN

1944-8244

Publication date

2017

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

General Materials Science

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1021/acsami.7b12228 (Access: Closed)