Kabushiki Kaisha Toyota Jidoshokki

National Institute of Advanced Industrial Science and Technology

Keio University

Masataka Nakanishi

Masakazu Murase

Yusuke Sugiyama

Nobuhiro Goda

Kazuhito Kawasumi

Tomohiro Niimi

Junichi Niwa

Hiroki Oshima

Takashi Mohri

Takeshi Kondo

Hiroshi Hirate

Tetsuo Sakai

Masanori Harata

Yoshihiro Nakagaki

Akira Kojima

Takuhiro Miyuki

Takashi Mori

Shigenori Koishi

Hitotoshi Murase

Mitsuharu Tabuchi

Toshikatsu Kojima

Masanori Morishita

Yuya Sato

Mutsumi Takahashi

Hirotaka Sone

Nagisa Watanabe

Osamu Ohmori

Akiko Shima

Kimihisa Yamamoto

Kazuaki Hokano

A production process for carbon-coated silicon material includes the step of: heating CaSi2 and a halogen-containing polymer at a temperature being a carbonization temperature or more of the halogen-containing polymer in a state where the CaSi2 and the halogen-containing polymer coexist.

Production process for carbon-coated silicon material

A nano silicon material having reduced amounts of oxygen (O) and chlorine (Cl) contained therein is provided. The nano silicon material contains fluorine (F) and nano-sized silicon crystallites. Generation of a layer in which oxygen (O) and chlorine (Cl) are present is suppressed due to the presence of fluorine (F), so that a decrease in the moving speed of lithium ions is suppressed. In addition, due to the presence of fluorine (F), the concentrations of oxygen (O) and chlorine (Cl) are reduced, so that reaction thereof with lithium ions is suppressed.

Nano silicon material, method for producing same, and negative electrode of secondary battery

Provided is a negative electrode active material including complex particles formed of: nano silicon aggregated particles produced by heating a layered polysilane represented by a composition formula of (SiH)and having a structure in which multiple six-membered rings formed from silicon atoms are connected; and a composited carbon layer formed from an amorphous carbon and at least covering one portion of the aggregated particles. A mean particle diameter Dof the aggregated particles is within a range of 0.2 &#x3bc;m to 30 &#x3bc;m, and a mean particle diameter Dof the complex particles is within a range of 0.5 &#x3bc;m to 40 &#x3bc;m.

Negative electrode active material, method for producing same, and electrical storage device

A negative-electrode active material is used for a negative electrode, the negative-electrode active material including: agglomerated particles including nanometer-size silicon produced by heat treating a lamellar polysilane having a structure in which multiple six-membered rings constituted of a silicon atom are disposed one after another, and expressed by a compositional formula, (SiH); and a carbon layer including amorphous carbon, and covering at least some of the agglomerated particles to be composited therewith. An electric storage apparatus including the same is not only able to reduce the irreversible capacity, but also able to inhibit the generation of 'SEI.'

Negative-electrode active material, production process for the same and electric storage apparatus

A silicon material useful as a negative electrode active material is provided. The silicon material has an Si/O atom ratio within a range of greater than 1/0.5 and not greater than 1/0.1 and a band gap within a range of greater than 1.1 eV and not greater than 2.1 eV. A secondary battery in which this silicon material is used as a negative electrode active material has long life.

Silicon material and negative electrode of secondary battery

A silicon material useful as a negative electrode active material is provided. The silicon material has a band gap within a range of greater than 1.1 eV and not greater than 1.7 eV. A secondary battery in which this silicon material is used as a negative electrode active material has improved initial efficiency.

Providing a negative-electrode material for nonaqueous-electrolyte secondary battery, the negative-electrode material including lithium silicate particles coated by a carbonaceous substance, a production process for the same, a negative electrode for nonaqueous-electrolyte secondary battery, and a nonaqueous-electrolyte secondary battery. A negative-electrode material for nonaqueous-electrolyte secondary battery includes lithium silicate particles having a surface at least some of which is coated by a carbonaceous substance formed by heating a carbon-containing compound at a thermal decomposition temperature of the carbon-containing compound or more and 1,100&#xb1;&#xb0; C. or less, the carbon-containing compound being a solid at ordinary temperature and exhibiting a zeta-potential absolute value being 60 or more against N-methyl-2-pyrrolidone (or NMP).

Negative-electrode material for nonaqueous-electrolyte secondary battery production process for the same, negative electrode for nonaqueous-electrolyte secondary battery, and nonaqueous-electrolyte secondary battery

A negative-electrode active material is provided, the negative-electrode active material including: a lamellar polysilane having a structure in which multiple six-membered rings constituted of a silicon atom are disposed one after another, and expressed by a compositional formula, (SiH), as a basic skeleton; and the negative-electrode active material containing copper in an amount of from 0.01 to 50% by mass. To contain copper results in upgrading electron conductivity. Consequently, an electric storage apparatus using the negative-electrode active material for one of the negative electrodes has upgraded rate characteristic, and also has augmented charged and discharged capacities.

Negative-electrode active material and electric storage apparatus

A nanometer-size silicon material produced by heat treating a lamellar polysilane exhibits Raman-shift peaks existing at 341&#xb1;10 cm, 360&#xb1;10 cm, 498&#xb1;10 cm, 638&#xb1;10 cm, and 734&#xb1;10 cmin a Raman spectrum, has a large specific surface area, and has a reduced SiO content.

Production process for nanometer-size silicon material

In a secondary battery, a negative electrode, an electrolytic solution for negative electrode, a diaphragm, an electrolytic solution for positive electrode, and a positive electrode are disposed in order. The negative electrode includes a negative-electrode active material that has an element whose oxidation-reduction potential is more 'base' by 1.5 V or more than an oxidation-reduction potential of hydrogen, and whose volume density is larger than that of lithium metal. The diaphragm includes a solid electrolyte transmitting ions of said element alone. A secondary battery with high volumetric density is provided.

Secondary battery

Provided is a novel lithium silicate-based material useful as a positive electrode material for lithium ion secondary battery. The lithium silicate-based compound is represented by LiFeSiO. The lithium silicate-based compound is a compound including: lithium (Li); iron (Fe); silicon (Si); and oxygen (O), and expressed by a composition formula, LiFeSiO(&#x2212;0.25&#x2266;&#x3b4;&#x2266;0.25, 0&#x2266;c&#x2266;0.5). The lithium silicate-based compound, of which iron (Fe) is trivalent, exerts a remarkable chemical stability as compared to LiFeSiO.

Lithium silicate-based compound, positive electrode active material for lithium ion secondary battery, and lithium ion secondary battery using the same

Providing a negative-electrode active material for nonaqueous-electrolyte secondary battery, the negative-electrode active material enabling an output characteristic to upgrade, a production process for the same, a negative electrode for nonaqueous-electrolyte secondary battery, and a nonaqueous-electrolyte secondary battery. The negative-electrode active material includes an Si-metal-carbon composite composed of: a metal/carbon composite matrix including at least one metal selected from the group consisting of Cu, Fe, Ni, Ti, Nb, Zn, In and Sn, at least one member selected from the group consisting of N, O, P and S, and amorphous carbon; and nanometer-size Si particles dispersed in the metal/carbon composite matrix.

Negative-electrode active material for nonaqueous-electrolyte secondary battery production process for the same, negative electrode for nonaqueous-electrolyte secondary battery, and nonaqueous-electrolyte secondary battery

Provided is a condensed polycyclic aromatic compound, having lithium ion responsivity and is suitable for lithium ion secondary battery applications, a production process thereof, a positive electrode active material containing that condensed polycyclic aromatic compound, and a positive electrode for a lithium ion secondary battery provided therewith, and further provided is a lithium ion secondary battery, having high capacity and cycling adaptability, that has the positive electrode as a constituent thereof. The condensed polycyclic aromatic compound has at least four imino groups in a molecule thereof.

Condensed polycyclic aromatic compound, production process of same, and positive electrode active material for lithium ion secondary battery containing same

To provide a sulfur-system positive electrode for lithium-ion battery, sulfur-system positive electrode which is good in the cyclability and the other characteristics, and a lithium-ion secondary battery including that positive electrode. In a positive electrode for lithium-ion secondary battery, the positive electrode having: a current collector; and an electrode layer that is formed on a surface of the current collector, and which includes a binder resin, an active material and a conductive additive, the positive electrode is characterized in that the active material includes a sulfur-modified polyacrylonitrile that is produced by heating a raw-material powder including a sulfur powder and a polyacrylonitrile powder in an enclosed nonoxidizing atmosphere; and the binder resin includes a polyimide resin and/or a polyamide-imide resin.

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Kariya, Japan

Masataka Nakanishi