Details

Autor(en) / Beteiligte

• Ren, Jian-Guo
• Wu, Qi-Hui
• Tang, Hao
• Hong, Guo
• Zhang, Wenjun
• Lee, Shuit-Tong

Titel

Germanium–graphene composite anode for high-energy lithium batteries with long cycle life

Ist Teil von

• Journal of materials chemistry. A, Materials for energy and sustainability, 2013-01, Vol.1 (5), p.1821-1826

Erscheinungsjahr

2013

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The high-energy lithium ion battery is an ideal power source for electric vehicles and grid-scale energy storage applications. Germanium is a promising anode material for lithium ion batteries due to its high specific capacity, but still suffers from poor cyclability. Here, we report a facile preparation of a germanium-graphene nanocomposite using a low-pressure thermal evaporation approach, by which crystalline germanium particles are uniformly deposited on graphene surfaces or embedded into graphene sheets. The nanocomposite exhibits a high Coulombic efficiency of 80.4% in the first cycle and a capacity retention of 84.9% after 400 full cycles in a half cell, along with high utilization of germanium in the composite and high rate capability. These outstanding properties are attributed to the monodisperse distribution of high-quality germanium particles in a flexible graphene framework. This preparation approach can be extended to other active elements that can be easily evaporated (e.g., sulfur, phosphorus) for the preparation of graphene-based composites for lithium ion battery applications.