Doctor of Philosophy, Fudan University (2017)
Bachelor of Engineering, Sun Yat-Sen University (2012)
High-Safety and High-Energy-Density Lithium Metal Batteries in a Novel Ionic-Liquid Electrolyte.
Advanced materials (Deerfield Beach, Fla.)
Rechargeable lithium metal batteries are next generation energy storage devices with high energy density, but face challenges in achieving high energy density, high safety, and long cycle life. Here, lithium metal batteries in a novel nonflammable ionic-liquid (IL) electrolyte composed of 1-ethyl-3-methylimidazolium (EMIm) cations and high-concentration bis(fluorosulfonyl)imide (FSI) anions, with sodium bis(trifluoromethanesulfonyl)imide (NaTFSI) as a key additive are reported. The Na ion participates in the formation of hybrid passivation interphases and contributes to dendrite-free Li deposition and reversible cathode electrochemistry. The electrolyte of low viscosity allows practically useful cathode mass loading up to 16 mg cm-2 . Li anodes paired with lithium cobalt oxide (LiCoO2 ) and lithium nickel cobalt manganese oxide (LiNi0.8 Co0.1 Mn0.1 O2 , NCM 811) cathodes exhibit 99.6-99.9% Coulombic efficiencies, high discharge voltages up to 4.4 V, high specific capacity and energy density up to 199 mAh g-1 and 765 Wh kg-1 respectively, with impressive cycling performances over up to 1200 cycles. Highly stable passivation interphases formed on both electrodes in the novel IL electrolyte are the key to highly reversible lithium metal batteries, especially for Li-NMC 811 full batteries.
View details for DOI 10.1002/adma.202001741
View details for PubMedID 32449260
A safe and non-flammable sodium metal battery based on an ionic liquid electrolyte.
2019; 10 (1): 3302
Rechargeable sodium metal batteries with high energy density could be important to a wide range of energy applications in modern society. The pursuit of higher energy density should ideally come with high safety, a goal difficult for electrolytes based on organic solvents. Here we report a chloroaluminate ionic liquid electrolyte comprised of aluminium chloride/1-methyl-3-ethylimidazolium chloride/sodium chloride ionic liquid spiked with two important additives, ethylaluminum dichloride and 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide. This leads to the first chloroaluminate based ionic liquid electrolyte for rechargeable sodium metal battery. The obtained batteries reached voltages up to ~4V, high Coulombic efficiency up to 99.9%, and high energy and power density of ~420Whkg-1 and ~1766 W kg-1, respectively. The batteries retained over 90% of the original capacity after 700 cycles, suggesting an effective approach to sodium metal batteries with high energy/high power density, long cycle life and high safety.
View details for DOI 10.1038/s41467-019-11102-2
View details for PubMedID 31341162
- Amphiphilic core-sheath structured composite fiber for comprehensively performed supercapacitor SCIENCE CHINA-MATERIALS 2019; 62 (7): 955–64
Stabilizing lithium into cross-stacked nanotube sheets with ultra-high specific capacity for lithium oxygen battery.
Angewandte Chemie (International ed. in English)
Although lithium-oxygen batteries possess high theoretical energy density and are considered as promising candidates for the next-generation power systems, how to enhance the safety and cycling efficiency of the lithium anodes while maintaining the high energy storage capability remains difficult. Here, we overcome this challenge by cross-stacking aligned carbon nanotubes into porous networks for ultrahigh-capacity lithium anodes to afford high-performance lithium-oxygen batteries. The novel anode shows a reversible specific capacity of 3656 mAh/g, approaching the theoretical capacity of 3861 mAh/g of pure lithium. When this anode is employed for lithium-oxygen full batteries, the cycling stability is significantly enhanced owing to the dendrite-free morphology and stabilized solid electrolyte interface. This work presents a new pathway to high performance lithium-oxygen batteries towards practical applications by designing cross-stacked and aligned structures for one-dimensional conducting nanomaterials.
View details for PubMedID 30575248
Alignment of Thermally Conducting Nanotubes Making High-Performance Light-Driving Motors.
ACS applied materials & interfaces
Light-actuating devices that can produce selective motions at small scales are highly desired for on-demand manipulation. For conventional photothermal motors that mostly encounter the homogenous light-induced heat diffusion at the liquid/air interface, it is challenging to effectively control the actuating direction and enhance the actuating speed. To this end, here, we explore aligned thermally conducting one-dimensional nanomaterials to make light-driving motors where the light-induced heat can be transmitted to the water surface along the length direction of the aligned one-dimensional nanomaterials to generate a localized surface tension gradient for high spatial resolution propulsion. When multiwalled carbon nanotubes were studied as a demonstration, the aligned active layer generated sufficient propulsion to drive a centimeter-sized motor that was 10 000 times higher in mass of the actuating layer on water. In addition, the actuating direction had been accurately controlled by varying the illuminated region of the active aligned nanotube layer. The resulting light-driving motors can move as fast as 4.19 cm/s (or 5.2 body length per second), which exceeded the previous motors based on the light activation.
View details for PubMedID 29999307