The Furukawa Electric Co., Ltd.

Furukawa Automotive Systems Inc.

Tamas Mihalffy

Noriyasu Iwane

Taiji Mitsuyama

Antal Kovats

Kazunori Mukasa

Naoya Takashima

Koichi Yokoyama

Zoltan Varallyay

Lorand Romvari

Shinichi Nomoto

Etsuzo Sato

Mamichi Tsuyuki

An optical fiber includes: a core made of silica based glass; a cladding made of silica based glass, the cladding having a refractive index that is lower than a maximum refractive index of the core; and a coating including a primary coating layer, and a secondary coating layer. An outer diameter of the cladding is less than 100 μm. A thickness of the primary coating layer is larger than or equal to 15 μm. A mode field diameter at a wavelength of 1310 nm is larger than or equal to 8.6 μm and smaller than or equal to 9.2 μm. An effective cutoff wavelength is smaller than or equal to 1260 μm. A bending loss at a wavelength of 1550 nm when bending is made at a diameter of 60 mm is smaller than or equal to 0.1 dB/100 turn.

Optical fiber

An optical fiber includes: a core made of silica-based glass; a cladding configured to cover an outer circumference of the core and made of silica-based glass having a refractive index smaller than a maximum refractive index of the core; and a coating configured to cover an outer circumference of the cladding. The cladding has an outer diameter of 120 μm or smaller, a mode field diameter at a wavelength of 1310 nm is 8.6 μm to 9.2 μm, an effective cut-off wavelength is 1260 μm or smaller, and a bending loss at a wavelength of 1550 nm in a case of bending at a diameter of 20 mm is 0.75 dB/turn or smaller.

[Object] To detect states of a plurality of secondary batteries whose kinds are different with high accuracy. [Organization] A measurement unit (voltage sensor, current sensor) measuring a current value of a current flowing at a secondary batteryand a voltage value of a voltage generated at the secondary battery by the current in a predetermined frequency; an optimization unit (CPU) optimizing element constants of an equivalent circuit model of the secondary battery based on the measured voltage value and the current value; an identification unit (CPU) identifying a kind of the secondary battery with reference to the optimized element constants of the equivalent circuit model; a storage unit (ROM) storing detection formulas which detect the state of the secondary battery by each kind of the secondary battery; an acquisition unit (CPU) acquiring the detection formula corresponding to the identified kind from the storage unit; and a detection unit (CPU) detecting the state of the secondary battery by applying the element constants to the acquired detection formula, are included.

Secondary battery state detecting device and secondary battery state detecting method

To provide a secondary battery state detecting device that decreases the deterioration in capacity of the secondary battery and is low in arithmetic cost. A secondary battery state detecting device that detects a state of a secondary battery includes discharge means (discharge circuit ()) for subjecting the secondary battery () to a pulse discharge, acquiring means (controller ()) for controlling the discharge means to subject the secondary battery to at least one pulse discharge, and acquiring a time variation of a voltage value at that time, calculating means (controller ()) for calculating a parameter of a predetermined function having time as a variable by fitting the variation of the voltage value acquired by the acquiring means using the predetermined function, and detecting means (controller ()) for detecting the state of the secondary battery on the basis of the parameter of the predetermined function calculated by the calculating means.

A full charge sensing apparatus for sensing a fully charged state of a secondary battery based on an equivalent circuit model of the secondary battery includes a measuring unit that measures a voltage and a current during charging of the secondary battery, a learning unit that performs a learning process on a plurality of parameters in the equivalent circuit model using a result of measurement of the measuring unit, and a determining unit that determines that the secondary battery is in a fully charged state in a case where, among the parameters on which the learning process has been performed by the learning unit, a parameter corresponding to a reaction resistance of the secondary battery is greater than a predetermined threshold.

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Budapest, Hungary

Tamas Mihalffy