Dendritic lithium (Li) growth hinders the applications of Li metal anode. Here, a fumed SiO2 is proposed as an electrolyte additive to realize uniform Li+ deposition. Due to the abundant hydroxyl group on the surface, the SiO2 particles as a pump provide an additional way for Li+ transport, resulting in a homogeneous Li+ flux. Moreover, SiO2 can also smooth the deposited Li and boost the formation of a LiF-rich SEI. As a result, the anode-free Li2S/Cu cell demonstrates a significantly improved rechargeability (1055 mAh g−1, 1st cycle; 523 mAh g−1, 200th cycle). Moreover, even with limited electrolyte (electrolyte/sulfur ratio, 7 µL mg−1) and Li (negative to positive capacity ratio, 3), the Li/S pouch cells can still maintain a high capacity of 689 mAh g−1 after 200 cycles. This work shows a simple and efficient way for constructing high-energy-density Li metal batteries.
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- General Materials Science