Kabushiki Kaisha Toyota Jidoshokki

Hiroki Oshima

Nobuhiro Goda

Takashi Mohri

Masataka Nakanishi

Masanori Harata

Manabu Miyoshi

Takeshi Kondo

Yusuke Sugiyama

Tomokuni Abe

Takeshi Maki

Takahiro Sugioka

Atsushi Saito

Tomohiro Niimi

Tatsuya Eguchi

Yuta Kawamoto

Jun Kaneda

Yuya Sato

Mutsumi Takahashi

Kanae Suzuki

Kisena Yoshida

The negative electrode includes a current collector, a negative electrode active material layer arranged on a surface of the current collector, and a protective layer arranged on a surface of the negative electrode active material layer. The negative electrode active material layer includes a first negative electrode active material having an aspect ratio defined as 'a'/'b' to fall in a range of from two or more to eight or less when a length of the major axis is defined &#x201c;a&#x201d; and a length of the minor axis is defined &#x201c;b.&#x201d; The protective layer includes a ceramic powder.

Negative electrode for nonaqueous electrolyte secondary battery and nonaqueous electrolyte secondary battery

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

[object Object]

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.

A positive electrode active material layer comprises a coating layer for coating at least part of surfaces of positive electrode active material particles. The coating layer comprises alternate layers of a cationic material layer containing a cationic material having a positive zeta potential and an anionic material layer containing an anionic material having a negative zeta potential under neutral conditions, and a material layer having a zeta potential of opposite sign to that of the positive electrode active material particles is bonded to the surfaces of the positive electrode active material particles. The coating layer is thin and uniform, and has a high strength for bonding to the positive electrode active material particles, so the coating layer suppresses direct contact of the positive electrode active material particles and an electrolytic solution even when a nonaqueous secondary battery is used at a high voltage.

Positive electrode for secondary battery, method for producing the same, and nonaqueous secondary battery

A positive electrode for lithium-ion secondary battery is provided, the positive electrode being able to endure high-temperature and high-voltage driving modes or operations. At least parts of the surface of positive-electrode active-material particles are covered by a polymer coating layer, and an amino group and phosphoric-acid group are included in the polymer coating layer. Since the polymer coating layer includes a phosphoric-acid-based polymer, capacity declines are inhibited at the time of cycle tests.

Positive electrode for lithium-ion secondary battery and production process for the same, and lithium-ion secondary battery

Provided is a negative electrode for a nonaqueous secondary battery which achieves both suppression of reductive decomposition of an electrolyte or an electrolytic solution and suppression of an increase in resistance. Also provided are a method for producing such a negative electrode and a nonaqueous secondary battery employing such a negative electrode. A polymer coating layer is formed so as to coat at least part of surfaces of negative electrode active material particles containing silicon oxide (SiO; 0.5&#x2266;x&#x2266;1.6). The polymer coating layer contains a cationic polymer having a positive zeta potential under neutral conditions. Since silicon oxide has a negative zeta potential, a thin uniform coating layer can be formed owing to Coulomb's force.

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Kariya, Japan

Hiroki Oshima