Lithium sulfur rechargeable battery is potentially low cost and high energy storage chemistry, because sulfur is an abundant element, and can be mined at low cost. However, LiS chemistry has many challenges due to the polysulfides dissolution, and inhomogeneous lithium metal deposition during charge and discharge process. We aim to address these challenges through design, synthesis and formulation of new electrolytes, and electrode engineering.
Zhao, Y. Z.; Fang, C.; Zhang, G. Z.; Hubble, D.; Nallapaneni, A.; Zhu, C. H.; Zhao, Z. W.; Liu, Z. M.; Lau, J.; Fu, Y. B.; Liu, G., A Micelle Electrolyte Enabled by Fluorinated Ether Additives for Polysulfide Suppression and Li Metal Stabilization in Li-S Battery. Front. Chem. 2020, 8, 9.
Ai, G.; Wang, Z. H.; Dai, Y. L.; Mao, W. F.; Zhao, H.; Fu, Y. B.; En, Y. F.; Battaglia, V.; Liu, G., Improving the over-all performance of Li-S batteries via electrolyte optimization with consideration of loading condition. Electrochim. Acta 2016, 218, 1-7.
The structure of the ant-nest network is famous for the smart spatial design with abundant storage space and multi interconnected channels between storage sites, which allows for efficient and fast transportation of food.
- Facilitate fast lithium ion transport
- Retain polysulfide dissolution
- Assist polysulfide precipitation
Ai, G.; Dai, Y. L.; Mao, W. F.; Zhao, H.; Fu, Y. B.; Song, X. Y.; En, Y. F.; Battaglia, V. S.; Srinivasan, V.; Liu, G., Biomimetic Ant-Nest Electrode Structures for High Sulfur Ratio Lithium-Sulfur Batteries. Nano Letters 2016, 16 (9), 5365-5372.
Polysulfide shuttling has been the primary cause of failure in lithium-sulfur (Li-S) battery cycling. In this work, an unexpected outcome of Li-S battery research shows that a substitution reaction between polysulfides and binders greatly immobilizes the shuttling polysulfides. The substitution reaction is verified by UV-visible spectra and X-ray photoelectron spectra. The immobilization of polysulfide is in situ monitored by synchrotron based sulfur K-edge X-ray absorption spectra. The resulting electrodes exhibite initial capacity up to 20.4 mAh/cm2, corresponding to 1199.1 mAh/g based on a micron-sulfur mass loading of 17.0 mg/cm2. Furthermore, nano-size sulfur adoption promotes an extra high capacity of 33.7 mAh/cm2, which is one of the highest areal capacity reported. The promoted performance is benefited from the controlled shuttle factor by nucleophilic substitution reaction. The nucleophilic substitution strategy demonstrated here for Li-S battery is of great significance and very promising for scale up production.
Ling, M.; Zhang, L.; Zheng, T. Y.; Feng, J.; Guo, J. H.; Mai, L. Q.; Liu, G., Nucleophilic substitution between polysulfides and binders unexpectedly stabilizing lithium sulfur battery. Nano Energy 2017, 38, 82-90.