Kabushiki Kaisha Toyota Jidoshokki

National Institute of Advanced Industrial Science and Technology

The University of Tokyo

Keio University

Japan Fine Ceramics Center

Junichi Niwa

Tetsuo Sakai

Kazuhito Kawasumi

Akira Kojima

Hitotoshi Murase

Toshikatsu Kojima

Masakazu Murase

Takayuki Hirose

Takuhiro Miyuki

Masataka Nakanishi

Tomoyuki Kawai

Atsuo Yamada

Yuki Yamada

Manabu Miyoshi

Mitsuharu Tabuchi

Yuta Ikeuchi

Kenji Usui

Masanori Morishita

Keiichi Hayashi

Yuichi Hirakawa

Nobuhiro Goda

Yoshihiro Nakagaki

Yusuke Yamamoto

Hiroyuki Sasaki

Kohei Mase

Yuki Hasegawa

Teiichi Kimura

Yuya Sato

Yasue Okuyama

Osamu Ohmori

Akiko Shima

Kimihisa Yamamoto

Kazuaki Hokano

Hideki Goda

Kazuhiro Izumoto

Electrolytic solution

An electrolytic solution for a power storage device, the electrolytic solution containing water as a solvent, wherein an amount of the solvent is greater than 4 mol and not greater than 15 mol with respect to 1 mol of an alkali metal salt.

Aqueous electrolytic solution for power storage device and power storage device including said aqueous electrolytic solution

An objective is to provide a novel aqueous electrolytic solution constituting an aqueous power storage device that stably operates even at a high voltage. An electrolytic solution for a power storage device contains water as a solvent and has a composition in which an amount of the solvent is not greater than 4 mol with respect to 1 mol of an alkali metal salt.

To provide a structural body having a new shape and including a garnet crystal structure. A structural body comprising LiMMO(5&#x2264;a&#x2264;8; 2.5&#x2264;b&#x2264;3.5; 1.5&#x2264;c&#x2264;2.5; 10&#x2264;d&#x2264;14; Mis at least one element selected from Al, Y, La, Pr, Nd, Sm, Lu, Mg, Ca, Sr, or Ba; and Mis at least one element selected from Zr, Hf, Nb, or Ta) including a garnet crystal structure, wherein

Structural body containing garnet-type ionic conductor

A lithium-ion secondary battery of the present invention comprises a positive electrode including a positive electrode active material composite formed by compositing a lithium silicate-based material and a carbon material, a negative electrode including a negative electrode active material containing a silicon, and an electrolyte. The lithium-ion secondary battery satisfies 0.8&#x3c;B/A&#x3c;1.2, where A is irreversible capacity of the positive electrode and B is irreversible capacity of the negative electrode.

Lithium-ion secondary battery and method for producing the same

Provided are a positive electrode active material for a sodium ion secondary battery, and a positive electrode and a sodium ion secondary battery using the material. The positive electrode active material for a sodium ion secondary battery comprises a lithium sodium-based compound containing lithium (Li), sodium (Na), iron (Fe), and oxygen (O).

Positive electrode active material for sodium ion secondary battery, positive electrode, and sodium ion secondary battery

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

To provide a lithium ion secondary battery electrode in which a coated layer is held on a surface of an active material layer over a long period of time to suppress decomposition of the electrolysis solution and to enhance the cyclability, a manufacturing process for the same, and a lithium ion secondary battery using the electrode. A lithium ion secondary battery electrode includes a current collector, an active material layer containing a binder formed on a surface of the current collector, and a coated layer formed on the surface of at least a part of the active material layer, wherein the coated layer is an acrylic type copolymer cured substance including an acrylic type main chain and a side chain having polyester or polyether graft-polymerized to the acrylic type main chain and the coated layer is chemically bonded with the binder.

Lithium secondary battery electrode including coated layer having acrylic copolymer chemically bonded to binder of active material layer and manufacturing process for the same

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

A production process for lithium-silicate-based compound according to the present invention is characterized in that: a lithium-silicate compound being expressed by Li2SiO3 is reacted with a transition-metal-element-containing substance including at least one member being selected from the group consisting of iron and manganese at 550&#xb0; C. or less within a molten salt including at least one member being selected from the group consisting of alkali-metal nitrates as well as alkali-metal hydroxides in an atmosphere in the presence of a mixed gas including carbon dioxide and a reducing gas. In accordance with the present invention, it is possible to produce lithium-silicate-based materials, which are useful as a positive-electrode active material for lithium-ion secondary battery, and the like, at low temperatures by means of relatively easy means.

Production process for lithium-silicate-based compound

To provide a lithium ion secondary battery electrode in which a coated layer is held on a surface of an active material layer over a long period of time to suppress decomposition of the electrolysis solution and to enhance the cyclability, a manufacturing process for the same, and a lithium ion secondary battery using the electrode. A lithium ion secondary battery electrode includes a current collector, an active material layer containing a binder formed on a surface of the current collector, and a coated layer formed on the surface of at least a part of the active material layer, wherein the coated layer contains a silicone-acrylic graft copolymer cured substance including an acrylic type main chain having a functional group and a side chain having a silicone graft-polymerized to the acrylic type main chain, and the coated layer is chemically bonded with the binder.

Lithium ion secondary battery electrode, manufacturing process for the same, and lithium ion secondary battery using the electrode

The present invention is one which provides a production process for lithium-silicate-system compound, the production process being characterized in that: a lithium-silicate compound being expressed by LiSiOis reacted with a substance including at least one member of transition-metal elements that is selected from the group consisting of iron and manganese at 400-650&#xb0; C. in a molten salt of a carbonate mixture comprising lithium carbonate and at least one member of alkali-metal carbonates that is selected from the group consisting of potassium carbonate, sodium carbonate, rubidium carbonate and cesium carbonate in a mixed-gas atmosphere including carbon dioxide and a reducing gas; and a positive-electrode active material for lithium-ion secondary battery that comprises a lithium-silicate-system compound being obtained by the aforesaid process.

Production process for lithium-silicate-system compound

A lithium silicate-based compound according to the present invention is expressed by a general formula, LiAMnCoMSiOCl(In the formula: 'A' is at least one element selected from the group consisting of Na, K, Rb and Cs; 'M' is at least one member selected from the group consisting of Mg, Ca, Al, Ni, Fe, Nb, Ti, Cr, Cu, Zn, Zr, V, Mo and W; and the respective subscripts appear to be as follows: 0&#x2266;&#x201c;a&#x201d;&#x3c;0.2; 0&#x2266;&#x201c;b&#x201d;&#x3c;1; 0&#x3c;&#x201c;x&#x201d;&#x3c;1; 0&#x2266;&#x201c;y&#x201d;&#x2266;0.5; &#x2212;0.25&#x2266;&#x201c;&#x3b1;&#x201d;&#x2266;1.25; and 0&#x2266;&#x201c;&#x3b2;&#x201d;&#x2266;0.05). The lithium silicate-based compound is used as a positive-electrode active material for secondary battery whose discharge average voltage is higher, and which is able to sorb and desorb lithium ions.

Lithium silicate-based compound and production process for the same, positive-electrode active material and positive electrode for use in lithium-ion secondary battery as well as secondary battery

Provided is a sulfur-modified polyacrylonitrile manufacturing method that is characterized in that a starting base powder that comprises sulfur powder and polyacrylonitrile powder is mixed and the mixture is heated in a non-oxidizing environment while outflow of sulfur vapor is prevented. Also provided are a cathode for lithium batteries that uses, as the active substance, the sulfur-modified polyacrylonitrile manufactured with the method, and a lithium secondary battery that includes the cathode as a component element. This enables the practical use of an inexpensive sulfur-based material as the cathode material for lithium secondary batteries, and in particular, a sulfur-based cathode material that enables higher output and has excellent cycle life characteristics, as well as other characteristics, and secondary lithium batteries using the same can be obtained.

Sulfur-modified polyacrylonitrile, manufacturing method therefor, and application thereof

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

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Kariya, Japan

Junichi Niwa