Lithium Battery Engineering

Randolph, NJ, United States

Lithium Battery Engineering

Randolph, NJ, United States
Time filter
Source Type

Yang C.-K.,Peking University | Qi L.-Y.,Peking University | Zuo Z.,Lithium Battery Engineering | Wang R.-N.,Lithium Battery Engineering | And 3 more authors.
Journal of Power Sources | Year: 2016

In this paper, the intrinsic impact of inner structure features on the electrochemical performances of LiNi0.6Co0.2Mn0.2O2 cathodes is for the first time systematically investigated. Three different spherical Ni0.6Co0.2Mn0.2(OH)2 precursors are successfully synthesized by controlling pH values and ammonia concentrations. Interestingly, via a further lithiation process, the final cathodes can gradually inherit the structural features, showing distinct particle arrangement and genetic orientation characteristics in the inner structures. Such a hereditary property can be well reined for customizing the grain-orientation, helping the growth of the inert crystal direction, reducing cation mixing and exposing the high active (100) or (010) lattice planes for lithiation/delithiation processes via an intrinsical way. The degree of grain-orientation of the primary particles turns out to be a critical factor in determining the long-term stability and power performances. Due to the reduced cation mixing degree and favorable lithium diffusion pathways, the ordered agglomerates with the grain growth along with [003] direction exhibit superior rate capability and good cycle stability. © 2016 Elsevier B.V.

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.

Qi L.-Y.,Peking University | Zhang Y.-W.,Peking University | Xin Y.-L.,Peking University | Zuo Z.-C.,Lithium Battery Engineering | And 3 more authors.
Nanoscale | Year: 2015

A one step in situ synthesis approach is developed to construct 3D nitrogen-doped reduced graphene oxides, in which olive-like multi-component metal oxides are homogeneously dispersed. The novel hybrid nanoarchitecture shows some particular properties derived from synergistic effects. The size of Fe/Co/O oxides is reduced and better controlled compared to that of individual oxides due to mutual dispersant interactions. Furthermore, the positive synergistic interaction between heterogeneous oxides and graphene nanosheets has effective control on the particle size and dispersion of nanoparticles. Taking advantage of the flexibility and the cohesiveness of graphene nanosheets, the obtained composite can be directly processed into a binder-free electrode through a unique time-saving "squeezing" process. The obtained electrode possesses a reprocessable feature, which provides possibilities for convenient storage and quick fabrication at any time and presents attractive electrochemical performance of robust long-term capability retention (562 mA h g-1 after 300 cycles at 10 A g-1) and superior rate performances (1162 mA h g-1 at 0.5 A g-1, 737 mA h g-1 at 5 A g-1, and 585 mA h g-1 at 10 A g-1). © The Royal Society of Chemistry 2015.

Li G.,University of Chinese Academy of Sciences | Li G.,Peking University | Huang Z.,Lithium Battery Engineering | Zuo Z.,Lithium Battery Engineering | And 2 more authors.
Journal of Power Sources | Year: 2015

The effect of surface property of LiNi1/3Co1/3Mn1/3O2 on the low temperature performance is seldom studied. Herein, the trace Ti surface-doped LiNi1/3Co1/3Mn1/3O2 exhibits enhanced discharge capacity under low temperature. After doping, the discharge capacity of LiNi1/3Co1/3Mn1/3O2 at -20°C is 51.3 mAh g-1 at 5C, which is near twice as much as the bare material (30.1 mAh g-1). Via the X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy and X-ray photoelectron spectroscopy analysis, it is confirmed that Ti doping on the surface significantly alters the surface property of LiNi1/3Co1/3Mn1/3O2 particle. The surface-doped Ti efficiently changes the lattice parameters, reduces the electrochemical reaction resistance and finally enhances the discharge capacity. The study clarifies the nature of trace Ti surface doping and is helpful for understanding the enhancement mechanism of the low temperature performance of LiNi1/3Co1/3Mn1/3O2. © 2015 Elsevier B.V. All rights reserved.

PubMed | Peking University and Lithium Battery Engineering
Type: Journal Article | Journal: ACS applied materials & interfaces | Year: 2016

An in situ simple and effective synthesis method is effectively exploited to construct MOF-derived grape-like architecture anchoring on nitrogen-doped graphene, in which ultrafine Fe3O4 nanoparticles are uniformly dispersed (Fe3O4@C/NG). In this hybrid hierarchical structure, new synergistic features are accessed. The graphene oxide plane with functional groups is expected to alleviate the aggregation problem in the MOFs growth. Moreover, the morphology and size of iron-based MOFs and carbon content are conveniently controlled by controlling the solution concentration of precursor. Through making use of in situ carbonization of the organic ligands in MOFs, Fe3O4 subunits are effectively protected by 3D interconnected conductive carbon at microscale. Consequently, when applied as anode materials, even as high as 10 A g(-1) after 1000 cycles, Fe3O4@C/NG still maintains as high as 458 mA h g(-1).

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.

Yoshida H.,Lithium Battery Engineering | Imamura N.,Lithium Battery Engineering | Inoue T.,Lithium Battery Engineering | Takeda K.,Lithium Battery Engineering | Naito H.,Japan Aerospace Exploration Agency
Electrochemistry | Year: 2010

Large capacity Li-ion cells with 100 Ah for satellite application had been developed in 1999, and calendar and cycle life characteristics of the cells had been evaluated under various test conditions with wide range of temperature (0°C - 60°C), depth of discharge (3% - 80% DOD), and state of charge (0% - 100% SOC). These tests were started in 1999, and the data have been accumulated until 2008 for around ten years. From these results, we have confirmed that GYT Space Li-ion cells have sufficient capability to achieve the mission life requirements for several kinds of artificial satellites. Furthermore, we have discovered that our simple life estimation model needs to be modified to consider SEI growth blocking mechanism. It means that the SEI growth is blocked by the adjacent SEI layers, therefore calendar capacity loss is affected by not only its test term, temperature, and state of charge but also its calendar capacity loss values. Our modified estimation formula is that a rate of calendar capacity loss is decreased in proportion to the 2.4 th power of the calendar capacity retention. By using the modified formula, the estimation results show very good fitting with the long term cell test data for ten years.

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.

Loading Lithium Battery Engineering collaborators
Loading Lithium Battery Engineering collaborators