Fuji Jukogyo Kabushiki Kaisha

Other

Subaru Corporation

Osamu Hatozaki

Nobuo Ando

Yukinori Hato

Tsutomu Fujii

Shinichi Tasaki

Hiromoto Taguchi

Kenji Kojima

Kohei Matsui

Risa Miyagawa

Noboru Oyama

Kaoru Kitakizaki

Mitsuru Nagai

Hideki Shibuya

Takayuki Noguchi

Yoshihito Watanabe

Atsuro Shirakami

Chisato Marumo

Masanori Haba

Tetsu Tatsuma

Risa Takahata

When an electrode material having a weight-average mesopore/macropore specific surface area within a specific range is used, there arises an expansion of a cell caused by the generation of decomposed gas from a component of electrolyte solution during the pre-doping process of lithium ions. A potential drop upon the pre-doping process is adjusted so as to reduce or suppress the expansion of the cell. Specifically, since the pre-doping speed is increased, the negative electrode can speedily reach the potential by which an SEI component made of lithium alkyl carbonate can be produced on the surface of the negative electrode. Consequently, the absolute amount of the gas produced by the decomposition of the electrolyte solution can be reduced, whereby the expansion of the electric storage device can be reduced.

Electric storage device and its production method

[Problem] The present invention aims to enhance a characteristic of a lithium ion electric storage device upon charging or discharging with high load, and increasing a working temperature range thereof. [Means for Solving Problem] In a positive electrode active material used for a lithium ion electric storage device, the BET specific surface area is 1500 m/g or more and 3000 m/g or less, the ratio A of the pore volume within the range of the pore diameter of 0.6 nm or more and less than 1 nm to the pore volume within the range of the pore diameter of 0.6 nm or more and 200 nm or less in the active material satisfies 0&#x2266;A&#x2266;0.80, and the ratio B of the active material of the pore volume within the range of the pore diameter of 1 nm or more and 6 nm or less to the pore volume within the range of the pore diameter of 0.6 nm or more and 200 nm or less in the active material satisfies 0.20&#x2266;B&#x2266;1.0. By virtue of this structure, the lithium ion electric storage device can be provided that is excellent in the charging/discharging characteristic when it is given a high load, and that can satisfactorily operate even under an environment of &#x2212;30&#xb0; C.

Positive electrode active material for lithium ion electric storage device, and lithium ion electric storage device using the same

A lithium ion capacitor includes a positive electrode, a negative electrode, and a non-protonic organic solvent electrolytic solution of a lithium salt. A positive electrode active material is a material capable of reversibly doping a lithium ion and/or an anion. A negative electrode active material is a material capable of reversibly doping a lithium ion. The lithium ion is doped in advance to either one or both of the negative electrode and the positive electrode so that a positive electrode potential after the positive electrode and the negative electrode are short-circuited is 2.0 V (relative to Li/Li) or less when capacitance per unit weight of the positive electrode is C(F/g), weight of the positive electrode active material is W(g), capacitance per unit weight of negative electrode is C(F/g), and weight of the negative electrode active material is W(g), a value of (C&#xd7;W)/(C&#xd7;W) is 5 or more.

Lithium ion capacitor

To present a carbon material which provides an electrical storage device not only ensuring a high energy density but also realizing a high output and an excellent low temperature performance. A negative electrode active material for an electrical storage device employing an aprotic organic solvent electrolyte solution containing a lithium salt as an electrolytes characterized in that it is made of a carbon material having a specific surface area of from 0.01 to 50 m/g and a total mesopore volume of from 0.005 to 1.0 cc/g, wherein volumes of mesopores having pore diameters of from 100 to 400 &#x212b; occupy at least 25% of the total mesopore volume.

Negative electrode active material for charging device

A lithium ion capacitor includes a positive electrode made of a material capable of reversibly doping and dedoping lithium ions and/or anions; a negative electrode made of a material capable of reversibly doping and dedoping lithium ions; and an electrolytic solution made of an aprotonic organic solvent electrolyte solution of a lithium salt. When the negative electrode and/or positive electrode and a lithium ion supply source are electrochemically brought into contact, lithium ions are doped in a negative electrode and/or positive electrode. A positive electrode potential after the positive electrode and negative electrode are short-circuited is 2.0 V (vs. Li/Li) or less. The positive electrode and/or negative electrode has a current collector made of a metal foil that has many holes that penetrate through both sides and have an average diameter of inscribed circles of the through-holes of 100 &#x3bc;m or less.

A lithium ion capacitor having high energy density, high output density, high capacity and high safety includes a positive electrode made of a material capable of being reversibly doped with lithium ions and/or anions, a negative electrode made of a material capable of being reversively doped with lithium ions, and an aprotic organic solution of a lithium salt as an electrolytic solution. Wherein, the positive electrode and the negative electrode are laminated or wound with a separator interposed between them, the area of the positive electrode is smaller than the area of the negative electrode. The face of the positive electrode is substantially covered by the face of the negative electrode when they are laminated or wound.

A QCM sensor including a sensor device, the sensor device having a crystal substrate, on both of front and rear surfaces of which a pair of electrodes are disposed so as to oppose with each other and the QCM sensor detecting and quantitatively analyzing components of a sample from either a variation in a fundamental resonant frequency or a variation in an impedance when a surface of one of the pair of electrodes is immersed into either a sample gas or a sample solution. The sensor device is arranged in a multi-channel structure such that four mutually opposing electrodes ( A through A, B through B) are disposed on both front and rear surfaces of the crystal substrate each electrode being arranged to enable a fixation of a receptor which is different for each component of a sample to be detected and quantitatively analyzed, whereby the QCM sensor detects and quantitatively analyzes once the components of one sample different for different electrodes.

QCM sensor

Growing community of inventors

Tokyo, Japan

Osamu Hatozaki