Oki Electric Industry Co., Ltd.

Hitachi, Ltd.

Vehicle Energy Japan Inc.

Renesas Technology Corp.

Hitachi Automotive Systems, Ltd.

Oki Data Corporation

Oki Semiconductor Co., Ltd.

Hironori Sasaki

Masahiro Uekawa

Takeshi Takamori

Yoshinori Maeno

Kyoko Kotani

Tsunenori Yamamoto

Shuichi Suzuki

Keisuke Shinozaki

Takeshi Miki

Kenji Yamaga

Takefumi Okumura

Atsushi Kawamura

Hideaki Okayama

Motoo Futami

Keiichiro Ohkawa

Shin Yamauchi

Kei Sakabe

Seiichiro Tabata

Katsunori Nishimura

Osamu Kubota

Ryohhei Nakao

Mitsutoshi Honda

Shuko Yamauchi

Takeshi Kamijoh

Kohei Honkura

Yutaka Okabe

Fanny Matthey

Yasuo Arishima

Yuki Takei

Chang Qing Xu

Toshiyuki Ariga

Chang-Qing Xu

A conventional secondary battery has a problem that an internal resistance is very high in a low SOC region and necessary output cannot be taken out. In a secondary battery including a positive electrode and a negative electrode, a capacity difference from a terminal potential of a positive electrode discharge curve to a terminal voltage of a battery discharge curve of the secondary battery with respect to a discharge capacity of the secondary battery is 14% to 26%.

Secondary battery

An electrolyte solution for lithium ion secondary cell capable of suppressing a decomposition reaction of a graphite negative electrode by optimizing an amount of a cyclic carbonate, and capable of improving a cell performance in a low temperature range. The electrolyte solution for lithium ion secondary cell of the present invention includes; 10 volume % to 20 volume % of ethylene carbonate (EC) and/or propylene carbonate (PC) as a cyclic carbonate; 0.38 mol/L to 0.75 mol/L of at least one selected from lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), or lithium bis(oxalate) borate (LiBOB) as a first lithium salt; and a lithium imide salt. A sum of the lithium imide salt and the first lithium salt is in a range of 0.5 mol/L to 1.5 mol/L, and a mole ratio of the cyclic carbonate/the first lithium salt is in a range of 3 to 5.

Electrolyte solution for lithium ion secondary battery

An appropriate upper limit voltage is set to enable maximum charging performance of a secondary battery to be exhibited while effectively suppressing degradation of the secondary battery. An assembled battery control unit determines an upper limit voltage during charge of the secondary battery and calculates chargeable power of the secondary battery based on the upper limit voltage. The assembled battery control unit has an upper limit voltage calculating unit which calculates a voltage history of the secondary battery based on time series data of a voltage of the secondary battery and which calculates the upper limit voltage based on the voltage history.

Battery control apparatus

Provided is a positive electrode for lithium ion secondary cell that includes an electrolyte holding layer excellent in electron conductivity, and a lithium ion secondary cell using the same. The present invention relates to a positive electrode for lithium ion secondary cell that includes a positive electrode current collector foil and positive electrode mixture layers laminated on both surfaces of the positive electrode current collector foil. The positive electrode mixture layer includes a first positive electrode active material layer, an electrolyte holding layer, and a second positive electrode active material layer. The first positive electrode active material layer, the electrolyte holding layer, and the second positive electrode active material layer contain positive electrode active materials, binders, and conductive agents containing carbonaceous material. A conductive agent ratio of the electrolyte holding layer is higher than conductive agent ratios of the first positive electrode active material layer and the second positive electrode active material layer. A positive electrode active material ratio and a binder ratio of the electrolyte holding layer are lower than positive electrode active material ratios and binder ratios of the first positive electrode active material layer and the second positive electrode active material layer.

Positive electrode for lithium ion secondary cell, and lithium ion secondary cell using same

An object of the present invention is to provide a lithium ion secondary battery enabling improvement of output characteristics at the time of charge and discharge at low temperature and at room temperature. A lithium ion secondary battery according to the present invention for achieving the above object includes a positive electrode plate () including a positive electrode mix layer, and a negative electrode plate () including a negative electrode mix layer (). The negative electrode mix layer () contains a graphite-type material (), metal oxide (), and a conductive assistant (). The conductive assistant () is a carbon material that does not dope or dedope lithium ions, and a mixing ratio of the conductive assistant () is 0.4 weight % or more and less than 1.2 weight % of weight of the negative electrode mix layer ().

Lithium ion secondary battery

Provided is a secondary battery system capable of suppressing degradation of a battery capacity. When it is determined that a battery pack is brought into a non-use state, a battery state detection unit in a battery controller compares an SOC of the battery pack calculated by a battery state operation unit and a standard SOC. When the SOC of the battery pack is higher than the standard SOC, the battery state detection unit in the battery controller calculates a capacity value in which the SOC of the battery pack becomes lower than the standard SOC, from a difference of the SOC of the battery pack and the standard SOC, and transmits the calculated capacity value to a cell controller. The cell controller discharges the battery pack, on the basis of the capacity value transmitted from the battery state detection unit.

Secondary battery system

A lens optical element including an on-chip lens with a convex surface formed at a top part of a column-shaped portion; and a light emitting surface disposed in a state where the light emitting surface is covered by a bottom portion of the column-shaped portion of the on-chip lens. The relationship between a lens height, which is defined as a height from the light emitting surface to a peak of the convex surface, a thickness of the column-shaped portion, and a refractive index of a structural material of the on-chip lens is set so that when the light emitting surface emits light, a state is produced where the convex surface of the on-chip lens appears to have uniform brightness.

Lens optical element and display apparatus

In order to provide a charge/discharge technology for controlling an assembled battery system without promoting degradation or reduction in the lifetime of the assembled battery system, the assembled battery system includes a function for controlling charge and discharge power of a plurality of units each including a secondary battery and a power converter as one unit, the plurality of units being electrically connected in parallel to each other. When each unit performs charge or discharge by at least one or more times, charge and discharge of the unit are controlled so as not to be performed until a predetermined pause time period elapses.

Battery energy storage system

Since in existent charge-discharge control the battery direct current resistance of a lithium ion battery increases at a low temperature or in a low SOC, the battery voltage may possibly exceed greatly the maximum allowable voltage instantaneously due to over-voltage during charging or may possibly decrease greatly to less than the minimum allowable voltage during discharging. If the lithium ion battery continuously lies in such a state the battery performance is degraded abruptly. The battery resistance of a lithium ion battery module is estimated in accordance with SOC and temperature of the lithium ion battery module, and current to charge is set properly based on the estimated battery resistance.

A rechargeable battery system that controls charge/discharge of a lithium ion rechargeable battery, includes: an internal resistance detection unit that detects or estimates an internal resistance value indicating an internal resistance at the lithium ion rechargeable battery; and a discharge control unit that executes control so as to set a discharge suspension period while the lithium ion rechargeable battery is discharged if the internal resistance value detected via the internal resistance detection unit during discharge of the lithium ion rechargeable battery exceeds a first threshold value.

System for controlling charging and discharging of lithium ion battery

Provided is a secondary battery system including: a battery controller which controls charge and discharge of a secondary battery; a total controller which controls the entire system; an ammeter which detects a charge current and a discharge current of the secondary battery; and a voltmeter which detects a voltage of the secondary battery, in which a direct current resistance of the secondary battery at the time of charge and a direct current resistance of the secondary battery at the time of discharge are obtained on the basis of a current value and a voltage value detected by the ammeter and the voltmeter, to thereby determine a temporary increase in the direct current resistance of the secondary battery caused by charge and discharge with a large current on the basis of a relation between the two obtained direct current resistances. Accordingly, in a secondary battery system used in a hybrid system, a wind power generating system, a photovoltaic power generating system, and the like, the situation where a direct current resistance thereof transitionally (temporarily) increases is simply detected on the basis of the usage situation of a secondary battery, to thereby accurately calculate the deterioration state of the secondary battery and thus enable an appropriate coping process, so that the life of the secondary battery can be extended.

Secondary battery system including an arrangement to determine a temporary increase in direct current resistance of the secondary battery

A camera module includes a sensor chip having a backside surface and a main surface including a sensor forming region and a sensor peripheral region surrounding the sensor forming region, in which a light receiving portion is disposed in the sensor forming region; a lens chip having a non-lens forming surface and a lens forming surface including a lens forming region and a lens peripheral region surrounding the lens forming region, in which a lens portion disposed in the lens forming region; a spacer portion for bonding the sensor peripheral region to the lens peripheral region with a specific space in between so that the light receiving portion faces the lens portion; and a cover including an opening portion for passing light from outside toward the lens portion and the light receiving portion.

Camera module and method of producing the same

The fuel cell system includes a fuel cell stack, a fuel cell temperature sensor for measuring the internal temperature of the fuel cell, a voltage sensor for measuring the power generation voltage of the fuel cell, a current sensor for measuring the current flowing from the fuel cell, a radiator for radiating heat generated by the fuel cell, a fan attached to the radiator for controlling the heat radiation amount, a cooling water pump for increasing the pressure of a cooling fluid, a bypass valve for controlling the cooling fluid amount entering the radiator, and a controller, on the basis of the voltage information measured by the voltage sensor, the temperature information measured by the temperature sensor, and the current information measured by the current sensor, for controlling at least one of the operation amount of the cooling water pump, the operation amount of the fan, and the cooling fluid amount flowing through the bypass valve.

Fuel cell with cooling method at start up

A separator for fuel cell comprising an electrolyte with ionic conductivity, a pair of electrodes with the electrolyte sandwiched therebetween, and a separatorfor individually supplying a fuel gas and an oxidizing agent gas to the pair of the electrodes, respectively, wherein the separatoris provided with a multilayered metal sheet with at least the outermost layer thereof, and a corrosion-resistant film covering the whole surface of the metal sheet in order to form a metal separator, and the metal separator is further provided with a reacting gas sealing unit, a reacting gas manifold junction unit, and a reacting gas rectification unit, formed of an elastic body.

Separator for fuel cell

An optical transmitter and receiver module which can enhance a coupling comprises a light source emitting the first light, a light-receiving section receiving the second light, a diffraction device changing the direction of travel of at least one of the first light and the second light, a first lens which condenses the first light, outgoing from the light source and entering through the medium of the diffraction device, onto a light input/output face of the optical fiber and condenses the second light outgoing from the optical fiber onto the light-receiving section through the medium of the diffraction device, and a second lens which inhibits a beam of the first light outgoing from the light source from diverging and allows it to enter the first lens through the medium of the diffraction device.

Growing community of inventors

Yamanashi, Japan

Hironori Sasaki