Sony Corporation

Nippon Steel Corporation

Toyota Jidosha Kabushiki Kaisha

Toa Corporation

Other

Nippon Steel Sumitomo Metal Corporation

Sumitomo Metal Industries, Inc.

Koji Moriguchi

Kazuhito Kamei

Noriyuki Negi

Hideya Kaminaka

Masaru Abe

Atsuo Omaru

Masayuki Nagamine

Tatsuo Nagata

Sukeyoshi Yamamoto

Mitsuhara Yonemura

Nobuhiro Okada

Kazuhiko Kusunoki

Hironori Daikoku

Motohisa Kado

Hidemitsu Sakamoto

Nobuyoshi Yashiro

Mitsuharu Yonemura

Takashi Fukuda

Ken'ichi Ejima

Tomoyuki Kakeshita

Takashi Ogura

Mitsuru Nakashima

Tomoyuki Terai

The negative electrode active material according to the present embodiment includes alloy particle containing an alloy component and oxygen of 0.50 to 3.00 mass %. The alloy component contains Sn: 13.0 to 40.0 at % and Si: 6.0 to 40.0 at %. The alloy particle contains: one or two phases selected from a D0phase in which the Si content is from 0 to 5.0 at % and a &#x3b4; phase in which the Si content is from 0 to 5.0 at %; one or two phases selected from an &#x3b5; phase in which the Si content is from 0 to 5.0 at % and an &#x3b7;' phase in which the Si content is from 0 to 5.0 at %; and an SiOx phase. The alloy particle has, in an X-ray diffraction profile, a peak having a largest integrated diffraction intensity in a range of 42.0 to 44.0 degrees of a diffraction angle 2&#x3b8;.

Negative electrode active material, negative electrode, and battery

A negative electrode active material is provided that is utilized in a nonaqueous electrolyte secondary battery, and that can improve the capacity per volume and charge-discharge cycle characteristics. The negative electrode active material according to the present embodiment contains an alloy having a chemical composition consisting of, in at %, Sn: 13.0 to 24.5% and Si: 3.0 to 15.0%, with the balance being Cu and impurities. The alloy particles contain a phase with a peak of the most intense diffraction line appearing in a range of 42.0 to 44.0 degrees of a diffraction angle 2&#x3b8;, the most intense diffraction line being a diffraction line having the largest integrated diffraction intensity in an X-ray diffraction profile. A half-width of the most intense diffraction line of the alloy particles is in a range of 0.15 to 2.5 degrees.

Provided is a negative electrode active material that can improve the capacity per volume and charge-discharge cycle characteristics of a nonaqueous electrolyte secondary battery represented by a lithium ion secondary battery. The negative electrode active material according to the present embodiment contains an alloy phase. The alloy phase undergoes thermoelastic diffusionless transformation when releasing or occluding metal ions. The negative electrode active material of the present embodiment is used in a nonaqueous electrolyte secondary battery. Thermoelastic diffusionless transformation refers to so-called thermoelastic martensitic transformation.

Negative electrode active material

An apparatus () for producing an SiC single crystal is used in the solution growth includes a seed shaft () and a crucible (). The seed shaft () has a lower end surface (S) to which an SiC seed crystal () is to be attached. The crucible () holds an Si&#x2014;C solution (). The seed shaft () includes a cylinder part (A), a bottom part (B), and a low heat conductive member (C). The bottom part (B) is located at the lower end of the cylinder part (A) and has the lower end surface (S). The low heat conductive member (C) is arranged on the upper surface of the bottom part (B) and has a thermal conductivity lower than that of the bottom part (B). This production apparatus can make the temperature within the crystal growth surface of the SiC seed crystal less liable to vary.

Apparatus for producing SiC single crystal and method for producing SiC single crystal

A production apparatus is used for a solution growth method. The production apparatus includes a seed shaft and a crucible. The seed shaft has a lower end surface to which an SiC seed crystal is attached. The crucible contains an SiC solution. The crucible includes a cylindrical portion, a bottom portion, and an inner lid. The bottom portion is disposed at a lower end of the cylindrical portion. The inner lid is disposed in the cylindrical portion. The inner lid has a through hole and is positioned below a liquid surface of the SiC solution when the SiC solution is contained in the crucible.

Apparatus for producing SiC single crystal by solution growth method, and method for producing SiC single crystal by using the production apparatus and crucible used in the production apparatus

Provided is a wireless microphone system comprising a microphone and a wireless receiver, wherein the wireless microphone system is provided with: a normal communication mode in which communication is performed by using a normal unique word (UWN) preset in both the microphone and the wireless receiver devices; a confidential setting mode in which a confidential unique word (UWX) is transmitted without being set in either of said devices; and a confidential communication mode in which communication is performed by both said devices by using the confidential unique word (UWX) set by the confidential setting mode.

Wireless microphone system

To provide a wireless microphone device that enables a circuit board, which is to be provided with an oscillation circuit, to be decreased in size without deteriorating radiation characteristics. The wireless microphone device is configured to include: a circuit boardthat is sectioned into circuit areasandand makes the respective circuit areas function as antenna elements of a dipole antenna; an oscillation circuitthat is arranged in the circuit areaand generates a high frequency signal on the basis of a voice signal from a microphone; a feeding path for feeding the high frequency signal to an electrically conductive layerin the circuit areathrough a feeding point positioned on the circuit areaside distant from the oscillation circuit; and a high frequency shield covering at least a part of the feeding path. The high frequency shield is formed by covering the feeding path with a metal casehaving an opening at a bottom face and conducting the metal caseto the electrically conducting layerin the circuit area

Wireless microphone device

A graphite powder suitable for a negative electrode material of a lithium ion secondary battery which assures a high discharging capacity not lower than 320 mAh/g is to be manufactured at a lower cost. Specifically, a graphite powder containing 0.01 to 5.0 wt % of boron and having a looped closure structure at an end of a graphite c-planar layer on the surface of a powder, with the density of the interstitial planar sections between neighboring closure structures being not less than 100/&#x3bc;m and not more than 1500/&#x3bc;m, and with dbeing preferably not larger than 3.3650 &#x212b;, is manufactured by (1) heat-treating a carbon material pulverized at an elevated speed before or after carbonization for graphization at temperature exceeding 1500&#xb0; C. or by (2) heat-treating the carbon material pulverized before or after carbonization at a temperature exceeding 1500&#xb0; C. for graphization and subsequently further heat-treating the graphized material at a temperature exceeding a temperature of the oxidating heat treatment and the heat treatment in the inert gas.

Graphite powders suited for negative electrode material of lithium ion secondary battery

A graphite powder suitable for a negative electrode material of a lithium ion secondary battery which assures a high discharging capacity not lower than 320 mAh/g is to be manufactured at a lower cost. Specifically, a graphite powder containing 0.01 to 5.0 wt % of boron and having a looped closure structure at an end of a graphite c-planar layer on the surface of a powder, with the density of the interstitial planar sections between neighboring closure structures being not less than 100/&#x3bc;m and not more than 1500/&#x3bc;m, and with dbeing preferably not larger than 3.3650 &#x212b;, is manufactured by (1) heat-treating a carbon material pulverized at an elevated speed before or after carbonization for graphization at temperature exceeding 1500&#xb0; C. or by (2) heat-treating the carbon material pulverized before or after carbonization at a temperature exceeding 1500&#xb0; C. forgraphization and subsequently further heat-treating the graphized material at a temperature exceeding a temperature of the oxidating heat treatment and the heat treatment in the inert gas.

A graphite powder suitable for a negative electrode material of a lithium ion secondary battery which assures a high discharging capacity not lower than 320 mAh/g is to be manufactured at a lower cost. Specifically, a graphite powder containing 0.01 to 5.0 wt % of boron and having a looped closure structure at an end of a graphite c-planar layer on the surface of a powder, with the density of the interstitial planar sections between neighboring closure structures being not less than 100/&mgr;m and not more than 1500/&mgr;m, and with d002 being preferably not larger than 3.3650 &angst;, is manufactured by (1) heat-treating a carbon material pulverized at an elevated speed before or after carbonization for graphization at temperature exceeding 1500&deg; C. or by (2) heat-treating the carbon material pulverized before or after carbonization at a temperature exceeding 1500&deg; C. for graphization and subsequently further heat-treating the graphized material at a temperature exceeding a temperature of the oxidating heat treatment and the heat treatment in the inert gas.

A graphite powder has surface closed-end structures in which the graphite c-plane layers of the graphite layer crystal lattices have closed-ends on the surface of the graphite powder by linking the ends of one or more pairs of the c-plane layers, leaving interstices which are open on the surface of the graphite. The number of open interstices is at least 100 and at most 1500 per micrometer in a c-axis direction of the graphite. Preferably, the graphite powder has a specific surface area of 1.0 m /g or less. Such a graphite powder can be prepared either by graphitizing a carbon material, which has been pulverized at a high speed under well-controlled conditions before and/or after the carbonization, or by subjecting a carbon material, which has been pulverized under well-controlled conditions before and/or after the carbonization, to graphitization and then to oxidative heat treatment at a temperature of 600-800&deg; C. and finally to heat treatment at a temperature of 800&deg; C. or higher in an inert gas. The graphite powder can be used to produce negative electrodes of lithium ion secondary batteries having a high discharge capacity of at least 320 mAh/g and a high charge/discharge coulombic efficiency of at least 90%.

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Tokyo, Japan

Koji Moriguchi