A5053657575- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Advanced Battery Technologies Research
- Extraction and Separation Processes
- Supercapacitor Materials and Fabrication
- Electron and X-Ray Spectroscopy Techniques
- Chemical Synthesis and Characterization
- Semiconductor materials and devices
- Semiconductor materials and interfaces
- Transition Metal Oxide Nanomaterials
- Inorganic Fluorides and Related Compounds
- Inorganic Chemistry and Materials
- ZnO doping and properties
- Graphene research and applications
- Ferroelectric and Piezoelectric Materials
- Advanced Memory and Neural Computing
- Tribology and Wear Analysis
- Conducting polymers and applications
- Multiferroics and related materials
- X-ray Spectroscopy and Fluorescence Analysis
- Polymer Nanocomposite Synthesis and Irradiation
- Advanced NMR Techniques and Applications
- Dielectric properties of ceramics
- Interconnection Networks and Systems
- Electrical and Thermal Properties of Materials
Toyota Central Research and Development Laboratories (Japan)
2012-2024
Toyota Motor Corporation (Switzerland)
2010-2014
Osaka City University
2001-2008
McMaster University
2008
University of Waterloo
2006-2008
Kyoto University
2008
Laboratoire de Réactivité et Chimie des Solides
2005-2006
Université de Picardie Jules Verne
2005
Centre National de la Recherche Scientifique
2005
Abstract Layered LiCo1/3Ni1/3Mn1/3O2 was prepared by a solid state reaction at 1000 °C in air and examined nonaqueous lithium cells. showed rechargeable capacity of 150 mAh g−1 3.5–4.2 V or 200 3.5–5.0 V. Operating voltage Li / 0.2–0.25 lower than that cell with LiCoO2 LiMn2O4 0.15–0.3 higher LiNiO2 LiCo1/2Ni1/2O2 due to complex solution mechanism.
Abstract We have successfully prepared a layered nickel manganese oxide of LiNi1/2Mn1/2O2 (a = 2.89 Å and c 14.30 in hexagonal setting) shown that this material may be possible alternative to LiCoO2 for advanced lithium batteries terms the operating voltage, rechargeable capacity, cycleability, safety, materials economy.
Reaction mechanism of was examined by ex situ X-ray diffraction (XRD) and electrochemical methods. According to XRD results, the change in hexagonal lattice parameters quite similar that , i.e., unit cell volume almost constant at indicating homogeneous phase reaction over an entire range. Reversible-potential measurements on against a lithium electrode were also carried out solid-state redox reactions described applying concept density states (EDS). Gibbs free-energy for obtained be which...
The microstructure of LiNi 0.8 Co 0.15 Al 0.05 O 2 positive electrode material before and after the first cycle was investigated by scanning transmission electron microscopy (STEM) energy loss spectroscopy (EELS). STEM EELS analysis shows that, cycling, there are very thin layers at grain boundaries that contain a small amount transition metal ions (particularly Ni) on Li sites. After cycle, thickness some boundary increases significantly, accompanied formation microcracks boundaries. Also,...
Factors affecting the cycling life of cylindrical lithium-ion batteries LiNi<sub>0.8</sub>Co<sub>0.15</sub>Al<sub>0.05</sub>O<sub>2</sub>(NCA) with graphite were examined in terms rechargeable capacity and polarization NCA derivatives Li<sub>z</sub>Ni<sub>0.8</sub>Co<sub>0.15</sub>Al<sub>0.05</sub>O<sub>2−δ</sub>(0.8 ≤<italic>z</italic>≤ 1.05).
A lithium cell of pelletized LiNi0.8Co0.15Al0.05O2 without carbon or binder was operated in a voltage window 4.2 – 2.5 V at C/40 rate 20°C for ten cycles, and the microstructure ten-cycled sample examined by scanning transmission electron microscopy (STEM), which compared with those pristine first-cycled one. Microcracks appeared after first cycle grain boundaries, widened are derived from 1 2% change unit volume during charge discharge. Grain boundary layers extended almost invariable...
The first-principles calculations on the lithium insertion materials have been done to give rationale for research advanced lithium-ion batteries. To apply computational methods, model crystals are constructed by assuming in-plane two-dimensional superlattices based -type structure three sides of a phase triangle Model consisting superlattice gives two transition metal elements in ratio 3 1 and 2 1. For 1, assumed, i.e., so-called "straight" "zigzag" models. these indicate that (i) is solid...
A single-phase, well-crystallized Li5V(PO4)2F2/carbon nanocomposite has been prepared by an optimized solid-state route, and its electrochemical behavior was examined as a positive electrode active material in lithium-ion batteries. The microcrystalline powder synthesized the reaction of amorphous VPO4/C with Li3PO4 LiF. Synthesis precursor utilized carbon to reduce V2O5 simultaneously create nanoparticle reactive material, amount being tailored result small excess at end increase bulk...
Coaxial-fibers bundled batteries in which the negative electrode made of carbon fibers, separator and positive are formed this order from inside proposed to be used as a framework power source for future applications.
Abstract Li[Ni1/2Mn3/2]O4 having a spinel-framework structure was prepared by two-step solid state reaction, i.e., crystallization at 1000 °C followed an oxidation 700 in air, and examined nonaqueous lithium cells. Thus showed low polarization stability against electrolyte with rechargeable capacity of about 110–130 mAh/g 4.7 V 10–30 4.0 vs Li. Capacity region ca. Li, which usually observed for the samples conventional method, can be minimized process °C. A 3-volt lithium-ion battery two...
Recent progresses on insertion materials for lithium-ion batteries are described. Understanding of solid state chemistry and electrochemistry LiCoO2, LiNiO2, LiMn2O4, LiC6, so forth was a first step their modification in terms solution among the same crystal family second step. However, innovation is restricted because limitation chemical species unless new concept introduced. Old, but quite so-called "superlattice" model with which one can design hypothetical lithium materials, calculate...
A new lithium vanadium fluorophosphate Li5V(PO4)2F2 has been synthesized by incorporation of LiF into α-Li3V2(PO4)3, and its structure determined single-crystal X-ray diffraction. The sample crystallizes in monoclinic symmetry, space group P21/c (No. 14), with lattice parameters a = 6.3589(4), b 10.7795(6), c 10.3836(6), β 90.019(1)°, Z 4. refinement was performed using total 3094 unique reflections, resulting agreement factors R wR(F2) 0.0422 0.0741, respectively. consists layers...
Charging lithium-ion batteries above the manufacturer's high-voltage protection, so-called overcharge, causes rapid and exothermic reactions, then violent thermal runaway may happen in worst case. Side (electro-)chemical reactions occurring at both positive negative electrodes during overcharge are complicated, but those have to be explored overcome durability safety challenges. In-situ synchrotron X-ray absorption diffraction technique for a battery of LiNi0.75Co0.15Al0.05Mg0.05O2 (NCA-Mg)...
In pursuit of high-capacity Mn-based oxides as positive electrode materials for lithium-ion batteries, the changes in charge-discharge curve due to spinel transition still stand way cycling stability. We found this study that Li1.12Mn0.74O1.60F0.40 (LMOF05) electrodes with a loose-crystalline rock salt structure (LCRS), which F is placed near Mn, show stable and high capacity (300 mA h g-1, 952 W kg-1) little change curve. demonstrated by K-edge soft X-ray absorption spectroscopy diffraction...
A long-life medium-power three-volt lithium-ion battery consisting of Li[Ni1/2Mn3/2]O4 (P4332) and the zero-strain lithium insertion material titanium oxide (LTO; Li[Li1/3Ti5/3]O4) was described with emphasis on processing method to prepare for applications. The preparation conditions were re-examined by thermogravimetric analysis, scanning electron microscopy, FT-IR, powder X-ray diffraction, electrochemical methods. Well-defined crystals having (111) facets octahedra are essential...