Researchers from the East China University of Science and Technology, Shanghai have synthesized a flexible freestanding silicon/reduced graphene oxide (Si/rGO) hybrid film anode for Li-ion batteries. The Si/rGO films, when applied as a free-standing LIBs anode, exhibit a high reversible specific capacity of 904 mAh g−1 at 200 mA g−1 (about 2 times higher than theoretical value of graphite anode), and maintain a long cycle life (650 mAh g−1 after 150 cycles).
A full flexible battery assembled based on the flexible film anode and commercial LiCoO2 as a cathode delivered a high specific capacity of 700 and 613 mAh g−1 at 50 mA g−1 after 15 cycles in flat and bent states, respectively.
They attributed the electrochemical performance mainly to the two-dimensional hollow nanostructure of silicon and the strong synergistic effect with rGO.
The researchers first synthesized hollow silicon nanosheets using a simple magnesiothermic reduction strategy. These hybridize with rGO into flexible films in a layer-by-layer assembly process.
A paper on their work in published in the Journal of Power Sources.
Haoxuan Zhang, Shilong Jing, Yanjie Hu, Hao Jiang, Chunzhong Li (2016) “A flexible freestanding Si/rGO hybrid film anode for stable Li-ion batteries,” Journal of Power Sources, Volume 307, Pages 214-219, doi: 10.1016/j.jpowsour.2015.12.107