Nissan Motor Company Limited

Central Glass Company, Limited

Yasuhiko Osawa

Shinji Yamamoto

Atsushi Ito

Tomohiro Kaburagi

Hiroshi Inaba

Kiyoshi Nakase

Masazumi Ishikawa

Yukitoshi Yanagida

The present invention provides a control device of a secondary battery. The control device of the secondary battery using, as a positive electrode material, a positive electrode active material that shows a difference of an open circuit voltage curve between during charge and discharge, has a judging unit that judges, on the basis of a charge-discharge state of the secondary battery, whether or not calculation of a current SOC of the secondary battery is possible; and a charge controlling unit that, when judged that the calculation of the current SOC of the secondary battery is not possible by the judging unit, charges the secondary battery up to a predetermined fully charged state.

Control device for secondary battery, charging control method, and SOC detection method

A control device of a secondary battery using, as positive electrode material, positive electrode active material showing a difference of an open circuit voltage curve between during charge and discharge, detects whether the secondary battery is in a charge state or a discharge state. When the secondary battery is in the charge state, the control device calculates, as a current SOC, a value that is lower than an SOC corresponding to a current open circuit voltage of the secondary battery on a reference SOC-open circuit voltage curve showing a relationship between the SOC and the open circuit voltage, which becomes a reference upon calculating the current SOC. When the secondary battery is in the discharge state, the control device calculates as the current SOC, a value that is higher than the SOC corresponding to the current open circuit voltage of the secondary battery on the reference SOC-open circuit voltage curve.

Control device for secondary battery, and SOC detection method

A solid solution lithium-containing transition metal oxide includes a compound represented by chemical formula (1): Li[NiCoMn[Li]]O, where a, b, c and d satisfy relationships: 0.39&#x2266;a&#x3c;0.75, 0&#x2266;b&#x2266;0.18, 0&#x3c;c&#x3c;1.00, 0.05&#x2266;d&#x2266;0.25, and a+b+c+d=1.5. The use of the solid solution lithium-containing transition metal oxide in a lithium ion secondary battery can contribute to decreasing the amount of hysteresis of the battery, achieving high energy efficiency, and ensuring a high discharge capacity.

Solid solution lithium-containing transition metal oxide and lithium ion secondary battery

A solid solution lithium-containing transition metal oxide includes a compound represented by chemical formula (1): Li[NiCoMn[Li]]O, where a, b, c and d satisfy relationships: 0&#x3c;a&#x2266;0.75, 0&#x2266;b&#x2266;0.5, 0&#x3c;c&#x2266;1.0, 0.05&#x2266;d&#x2266;0.25, and a+b+c+d=1.5. A dQ/dV curve obtained in such a manner as to differentiate an open circuit voltage curve on a discharge side obtained by charging and discharging a lithium ion secondary battery using the compound as a positive electrode active material, fulfills math formula (1): A/B&#x2266;1.0 (where A represents a dQ/dV value at peak A located in a range from 3.0 V to 3.5 V in the dQ/dV curve, and B represents a dQ/dV value at peak B located in a range from 3.5 V to 4.0 V in the dQ/dV curve).

In an electrochromic (EC) display device having oppositely arranged two EC electrode layers, two kinds of EC materials each of which takes on a characteristic color by electrochemical oxidation, or by electrochemical reduction, are used in the two EC electrode layers, respectively, on condition that the characteristic color of one EC material differs from the color of the other EC material. For example, Prussian blue which colors in blue by oxidation and polytriphenylamine which colors in bronze by oxidation are used in combination. An alternative example is using a combination of WO.sub.3 which colors in blue by reduction and V.sub.2 O.sub.5 which colors in green by reduction. Since electrochemical oxidation of one EC electrode layer is usually accompanied by reduction of the opposite EC electrode layer, this EC device can be operated so as to selectively and alternately exhibit at least two different colors aside from colorless transparency.

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Yokosuka, Japan

Yasuhiko Osawa