Kabushiki Kaisha Toyota Jidoshokki

The University of Tokyo

Nobuhiro Goda

Yusuke Sugiyama

Takeshi Kondo

Takashi Mohri

Hiroki Oshima

Masataka Nakanishi

Masanori Harata

Yoshihiro Nakagaki

Masakazu Murase

Tomohiro Niimi

Atsuo Yamada

Yuki Yamada

Manabu Miyoshi

Tomoyuki Kawai

Kohei Mase

Tomokuni Abe

Yuki Hasegawa

Yuta Kawamoto

Mutsumi Takahashi

Takahiro Sugioka

Junichi Niwa

Hiroshi Hirate

Jun Kaneda

Yasuhiro Yamaguchi

Yuya Sato

Yushi Kondo

Shigenori Koishi

Yuta Nakagawa

Kensuke Yotsumoto

Hirotaka Sone

Kisena Yoshida

An electrolytic solution of a nonaqueous electrolyte secondary battery contains a metal salt, and an organic solvent having a heteroatom and satisfies Is&#x3e;Io, when an intensity of an original peak of the solvent is represented as Io and an intensity of a peak resulting from shifting of the original peak is represented as Is. For the negative electrode, (1) a graphite whose G/D ratio of G-band and D-band peaks in a Raman spectrum is not lower than 3.5; (2) a carbon material whose crystallite size, calculated from a half width of a peak appearing at 2&#x3b8;=20 degrees to 30 degrees in a X-ray diffraction profile is not larger than 20 nm; (3) silicon element and/or tin element; (4) a metal oxide configured to occlude and release lithium ions; or (5) a graphite whose ratio (long axis/short axis) is 1 to 5.

Nonaqueous electrolyte secondary battery

A polymer compound to be used as a binder for a negative electrode of a power storage device is provided. The polymer compound is formed by condensation of a polyacrylic acid and a polyfunctional amine represented by the following general formula (1), where X is a ring structure having 1 to 3 benzene rings; and Cto Care each a carbon atom constituting a benzene ring in the ring structure. 

Polymeric binder of polyacrylic acid, polyfunctional amine, and linking benzene ring

A negative electrode active material is composed of a silicon material coated with a carbon layer containing a Group 4 to 6 metal. A method for producing a negative electrode active material includes a step of decomposing a compound containing the Group 4 to 6 metal and a carbon source by heating in the presence of a silicon material, the compound, and the carbon source.

Negative electrode active material

A method for producing a silicon material, the method including:

Method for producing silicon material

A polymer compound, which is used as a binder for a negative electrode of an electricity storage device, is obtained by condensation of a vinyl polymer that contains a carboxyl group and a third compound that is selected from among an aromatic multifunctional amine, phosphorous acid, phosphorous acid ester, trialkoxysilane, and phosphoric acid.

Polymer compound, intermediate composition, negative electrode, electricity storage device, slurry for negative electrodes, method for producing polymer compound, and method for producing negative electrode

To provide a nonaqueous electrolyte secondary battery that suppresses elution of Al from a positive electrode current collector formed of aluminum or an aluminum alloy, and is superior in thermal characteristics and input-output characteristics. Provided is a nonaqueous electrolyte secondary battery including a positive electrode, a negative electrode, and an electrolytic solution. The positive electrode has a positive electrode current collector formed of aluminum or an aluminum alloy. The electrolytic solution contains a metal salt and an organic solvent having a heteroelement. Regarding an intensity of a peak derived from the organic solvent in a vibrational spectroscopy spectrum of the electrolytic solution, Is&#x3e;Io is satisfied when an intensity of an original peak of the organic solvent is represented as Io and an intensity of a peak resulting from shifting of the original peak is represented as Is.

A polymer compound is formed by condensing a polyacrylic acid having some of carboxyl groups converted into a lithium salt with a polyfunctional amine represented by the following general formula (1). A chain structure constituted by the polyacrylic acid has free carboxyl groups and carboxyl groups converted into a lithium salt. Y is a straight-chain alkyl group having 1 to 4 carbon atoms, a phenylene group, or an oxygen atom. R1 and R2 are each independently one or more hydrogen atoms, a methyl group, an ethyl group, a trifluoromethyl group, or a methoxy group.

Polymer compound, intermediate composition, negative electrode, electrical storage device, slurry for negative electrode, method for producing polymer compound, and method for producing negative electrode

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

Cycle characteristics of a nonaqueous secondary battery are to be improved. An active material including: a first active material that contains a nano silicon produced by heating a layered polysilane represented by a composition formula (SiH)and having a structure in which multiple six-membered rings formed from silicon atoms are connected; and a second active material that contains a graphite, is used in a negative electrode. With this, expansion and contraction due to stress during charging and discharging can be mitigated, and thereby cycle characteristics improve.

Negative electrode for nonaqueous secondary battery and nonaqueous secondary battery, negative electrode active material and method for producing same, complex including nano silicon, carbon layer, and cationic polymer layer, and method for producing complex formed of nano silicon and carbon layer

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

Provided is a method for producing a CaSi-containing composition, the method including:

[object Object]

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.

Growing community of inventors

Kariya, Japan

Nobuhiro Goda