A team from Chonnam National University and the Korea Advanced Institute of Science and Technology (KAIST) have developed a 3D nanoarchitecture of germanium (Ge) coated with carbon (3D-Ge/C) for use as ultra-high rate anodes for Li-ion batteries. The 3D-Ge/C shows excellent cyclability: almost 86.8% capacity retention, corresponding to a charge capacity of 1216 mAh g-1 even after 1000 cycles at a 2 C-rate.
The high average reversible capacity of 1122 mAh g-1 was maintained at a high charge rate of 100 C (160 A g-1). Even at an ultrahigh charge rate of 400 C (640 A g-1), an average capacity of 429 mAh g-1 was attained. Further, the full cell composed of 3D-Ge/C anode and LiCoO2 cathode exhibited excellent rate capability and cyclability with 94.7% capacity retention over 50 cycles.
A paper on their work is published in the RSC journal Energy & Environmental Science.
3D-Ge/C, which offers a high energy density as batteries as well as a high power density like supercapacitors, is expected to be used in a wide range of electrochemical devices.—Ngo et al.
Duc Tung Ngo, Hang. T. T Le, Chanhoon Kim, Jae-Young Lee, John G Fisher, Il-Doo Kim and Chan-Jin Park (2015) “Mass-scalable Synthesis of 3D Porous Germanium-Carbon Composite Particles as an Ultra-high Rate Anode for Lithium Ion Batteries” Energy Environ. Sci. doi: 10.1039/C5EE02183A