摘要
The practical application of lithium-sulfur (Li-S) batteries is hampered by the insulative nature of sulfur, sluggish electrochemical kinetics, and large volume variation, which result in capacity-fading at a large current density and poor cycling stability. Herein, a three-dimensional (3D) aluminum photonic crystal encapsulating sulfur (APC@S) composite as a binder-free cathode for Li-S battery is reported. The 3D APC@S cathode can deliver a fantastic capacity of 1,517.8 mAh·g^(−1) at 0.5 C, and retains 712.7 mAh·g^(−1) after 1,500 cycles at 2 C with a decay rate of 0.02% per cycle. Even at a high rate of 5 C, the reversible capacity can still maintain at 680.7 mAh·g^(−1) after 1,000 cycles with a capacity retention of 74.8%. Furthermore, the assembled soft-packaged Li-S battery also exhibits high reversible capacity and stable cycling performance. The excellent electrochemical performance is attributed to the 3D hierarchical and continuously porous structure and high conductive aluminum-wall, which can effectively trap polysulfides, confine the volume expansion on cycling, and accelerate electron/ion transfer. It is expected that this high conductive metal cathode has a great future for the application of energy storage devices.
基金
This work described in this paper was supported by the National Natural Science Foundation of China(Nos.51673115 and 51373097)
Moreover,we thank the support of the Shanghai Jiao Tong University Medical Engineering Cross Research Fund Project(No.YG2016MS19).
