Xue B.,Lithium Battery Engineering |
Calvez L.,French National Center for Scientific Research |
Allix M.,French National Center for Scientific Research |
Delaizir G.,European Ceramic Center 12 Rue Atlantis Cedex 87068 France |
Zhang X.-H.,French National Center for Scientific Research
Journal of the American Ceramic Society | Year: 2016
In this article, we put forward the possibility to prepare amorphous powder from chalcogenide compositions usually located out of the glassy domain when synthesized via a conventional melt-quenching technique. Both X-ray diffraction and DSC techniques were used to demonstrate that the original Ge15Ga20S65 composition can be prepared in the amorphous state by using mechanical milling starting from raw metallic elements. Subsequent hot-pressing by spark plasma sintering in a graphite die above the glass transition temperature leads to sintered pellets presenting a high rate of nanocrystals of about 30 nm. These as-made glass-ceramic materials present promising transparency in the infrared range. © 2016 American Ceramic Society.
Agency: Department of Defense | Branch: Army | Program: SBIR | Phase: Phase I | Award Amount: 67.29K | Year: 2010
High power rechargeable lithium batteries are desired for a wide variety of military products. Increasingly powerful and sophisticated military and civilian equipment require higher power batteries to function reliably under various conditions. Rechargeable lithium battery cells currently available have about 4.7kW/kg specific power for continuous discharge. By improving existing materials, electrode and cell designs in lithium-ion, the battery power density and specific power can be vastly improved. This work will also achieve no voltage delay, even after long storage periods, operability in a wide range of temperatures, long storage life, and safety.
Agency: Department of Defense | Branch: Navy | Program: SBIR | Phase: Phase I | Award Amount: 69.85K | Year: 2010
In recent years a new separator, developed under SOCOM funding, proved to prevent failure during overcharge by limiting the cell voltage and shunting the current. Tests have been done on 4.7Ah cells charged at C/2 and have been demonstrated to successfully continue to cycle after 300% overcharge. This separator also provides thermal shutdown at 90 - 110„aC and is structurally stable to 180„aC. It is proposed to combine this latest development of a new separator with other design-in technologies to produce intrinsically safe, large format cells. These cells will be designed to provide thermal management and will contain the safest of high energy cathode materials in order to still provide 175 - 200 Wh/kg at the cell level. These large cells will be tested and revised as necessary to provide and demonstrate intrinsic safety. A battery will then be designed using these cells and incorporating thermal management systems thus providing a large battery for submersibles with significantly improved safety against catastrophic events.
Xin Y.,Peking University |
Qi L.,Peking University |
Zhang Y.,Peking University |
Zuo Z.,Lithium Battery Engineering |
And 2 more authors.
Chemical Communications | Year: 2015
A novel organic solvent-assisted freeze-drying pathway, which can effectively protect and uniformly distribute active particles, is developed to fabricate a free-standing Li2MnO3·LiNi1/3Co1/3Mn1/3O2 (LR)/rGO electrode on a large scale. Thus, very high energy density and power density are realized for LR materials with robust long-term cyclability. © The Royal Society of Chemistry 2015.
Qi L.-Y.,Peking University |
Zhang Y.-W.,Peking University |
Zuo Z.-C.,Lithium Battery Engineering |
Xin Y.-L.,Peking University |
And 4 more authors.
Journal of Materials Chemistry A | Year: 2016
Unlike conventional carbon coating strategies which only focus on the macrodimension to enhance electrical conductivity and alleviate volume variation for high-capacity metal oxide anode materials, a hierarchically raspberry-like microstructure embedded with three-dimensional carbon-coated Fe3O4 quantum dots is built for ultrafast rechargeable sodium ion batteries. Taking advantage of using metal organic frameworks (MOFs) as templates, it realizes an in situ quantization process in which Fe3O4 quantum dots are formed and uniformly embedded in microcarbon coating protection. Due to the short diffusion length and integrated hierarchical conductive network, the electrode combines supercapacitor-like rate performance (e.g., less than 6 minutes to full charge/discharge) and battery-like capacity (e.g., maintaining >90% of theoretical capacity). An interesting surface-induced process which imitates pseudocapacitive behaviors in supercapacitors is analyzed in detail. This proof-of-concept study and insightful understanding on sodium storage in this investigation may inherently solve the widely encountered problems existing in high-capacity metal oxide anode materials and point out new directions for the future development of ultrafast rechargeable sodium ion batteries. © 2016 The Royal Society of Chemistry.