1. A Full Li–S Battery with Ultralow Excessive Li Enabled via Lithiophilic and Sulfilic W 2 C Modulation
- Author
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Benben Wei, Xin Wang, Chaoqun Shang, Guofu Zhou, and Eser Metin Akinoglu
- Subjects
Battery (electricity) ,010405 organic chemistry ,Organic Chemistry ,Nucleation ,chemistry.chemical_element ,General Chemistry ,Current collector ,010402 general chemistry ,01 natural sciences ,Redox ,Catalysis ,Cathode ,0104 chemical sciences ,law.invention ,chemistry ,Nanocrystal ,Chemical engineering ,Chemisorption ,law ,Lithium - Abstract
The practical application of Li-S batteries demands low cell balance (Licapacity /Scapacity ), which involves uniform Li growth, restrained shuttle effect, and fast redox reaction kinetics of S species simultaneously. Herein, with the aid of W2 C nanocrystals, a freestanding 3D current collector is applied as both Li and S hosts owing to its lithiophilic and sulfilic property. On the one hand, the highly conductive W2 C can reduce Li nucleation overpotentials, thus guiding uniform Li nucleation and deposition to suppress Li dendrite growth. On the other hand, the polar W2 C with catalytic effect can enhance the chemisorption affinity to lithium polysulfides (LiPSs) and guarantee fast redox kinetics to restrain S species in cathode region and promote the utilization of S. Surprisingly, a full Li-S battery with ultralow cell balance of 1.5:1 and high sulfur loading of 6.06 mg cm-2 shows obvious redox plateaus of S and maintains high reversible specific capacity of 1020 mAh g-1 (6.2 mAh cm-2 ) after 200 cycles. This work may shed new sights on the facile design of full Li-S battery with low excessive Li supply.
- Published
- 2020