Gs Yuasa International Ltd.

Kenichi Sejima

Takeyuki Shiraishi

Masashi Nakamura

Yoshihiko Mizuta

Atsushi Fukushima

Shinya Kitano

Hiroshi Sekiguchi

Tomoshige Inoue

Hidefumi Hasegawa

An open circuit voltage estimation device for estimating an open circuit voltage of an electric storage device includes a voltage measurement portion and a controller. The voltage measurement portion measures terminal voltages of the electric storage device. The controller is configured to: control the voltage measurement portion to measure the terminal voltages; store the terminal voltages in association with elapsed time since charge or discharge completion time; calculate a variation in terminal voltage per unit time at predetermined elapsed time since the charge or the discharge of the electric storage device is complete based on the terminal voltages measured by the voltage measurement portion; and estimate the open circuit voltage based on the predetermined elapsed time, the voltage at the predetermined elapsed time, and the variation.

Open circuit voltage estimation device, condition estimation device, and method of estimating open circuit voltage

Provided is an estimation device for estimating an actual capacity of an energy storage device or a total reduction amount of the actual capacity. The estimation device includes a processor which is configured to calculate the actual capacity of the energy storage device or the total reduction amount of the actual capacity based on approximation data where a capacity change curve indicative of a transition of the actual capacity or a transition of the total reduction amount of the actual capacity with respect to an elapsed time is approximated by a plurality of straight lines.

Estimation device and estimation method

The present invention is to improve the estimation accuracy of an SOC of a storage element. A storage element management device disclosed in the present description is a battery management devicethat determines an SOC range indicating a state-of-charge of a secondary battery, and has a constitution including a central processing unitthat sets an overlapping range between an SOC range (i) R, determined by a current integration method, and an SOC range (v) R, determined by a voltage reference method in a stage where the SOC range (i) Ris determined by the current integration method, as a new SOC range R

Energy storage device management apparatus, energy storage device module, vehicle, and energy storage device management method

A management device manages a secondary battery which includes a positive electrode having an active material with a characteristic where a potential flat portion exists in a relationship between a capacity and a potential. The management device includes a management unit which detects an occurrence of temporary degradation of the secondary battery when an SOC correlation associated value which is associated with an SOC of the secondary battery is acquired and the SOC which corresponds to the acquired SOC correlation associated value is equal to or less than a preset prescribed SOC or when a state value relating to a voltage of the secondary battery is acquired and a magnitude relationship between the acquired state value relating to the voltage of the secondary battery and a preset threshold value satisfies a predetermined condition.

Management device for secondary battery, and method of managing secondary battery

A state estimation device includes: a current integration unit configured to integrate a current that flows through the energy storage device; and a first estimation unit configured to estimate a full-charge capacity of the energy storage device. The energy storage device has a correlation characteristic of correlation between a residual capacity C and an open voltage V, the correlation characteristic including a constant region in which a time change in the correlation characteristic is relatively smaller than an other region. The first estimation unit performs: calculation of a residual capacity Cp of the energy storage device at a measuring point P based on an open voltage Vp of the energy storage device at the measuring point P included in the constant region, and on the correlation characteristic; and estimation of a full-charge capacity Co of the energy storage device based on the residual capacity Cp at the measuring point P that has been calculated, and on an accumulated charge-discharge amount X of the energy storage device from a full-charge state to the measuring point P, the full-charge state satisfying a full charge condition.

State estimation device and state estimation method

An energy storage device management method for deciding an SOC estimated value includes: preparing first and second SOC estimation methods for estimating an SOC; and employing a predetermined value as the SOC estimated value when a first SOC region and a second SOC region are different. V-SOC correlation between a voltage and the state of charge of the energy storage device is sectioned into a plurality of SOC regions. The first SOC region is the SOC region that the SOC estimated by the first SOC estimation method belongs to, and the second SOC region is the SOC region that the SOC estimated by the second SOC estimation method belongs to. The predetermined value is set to a value close to a boundary value on a side close to the first SOC region of boundary values sectioning the second SOC region, or a value between the boundary value and an intermediate value of the second SOC region.

Energy storage device management apparatus, energy storage device management method, energy storage device module, energy storage device management program, and movable body

The state of charge (SOC) estimation device includes a memory and a controller component. The memory stores data on a first correlation between an elapsed time and an estimation error in SOC estimation. The controller component executes a first estimation process and a second estimation process. The first estimation process is for estimating a first SOC and a first estimation error of the electric storage device in a non-charge/discharge state based on a terminal voltage and the elapsed time. The second estimation process is for estimating a second SOC and a second estimation error of the electric storage device in a charge/discharge state based on an accumulated charge/discharge current. The controller component calculates a total error from the first estimation error and the second estimation error. The controller component estimates the first estimation error when the elapsed time becomes equal to or longer than a reference time.

State of charge estimation device and method of estimating state of charge

A state estimation device includes: a voltage detecting unit that detects voltages of energy storage devices; and an estimating unit that estimates a charge amount difference between at least two of the energy storage devices. At a reference time point T0 during constant current charging, the estimating unit performs: specific voltage setting for setting, as a specific voltage V0, a voltage of a low-voltage energy storage device at the reference time point T0; time obtaining for obtaining a time point at which a voltage of a high-voltage energy storage device reaches the specific voltage V0; and charge amount difference estimating for estimating the charge amount difference between the at least two energy storage devices based on the reference time point T0, the time point obtained in the time obtaining process, and a current flowing through the plurality of energy storage devices during the constant current charging.

State estimation device, energy storage module, vehicle, and state estimation method

A condition estimation device for estimating condition of an electric storage device includes a voltage detector and a controller. The voltage detector is configured to detect a voltage of the electric storage device. The controller is configured to perform a distinctive point detection process to detect a distinctive point based on the voltage detected by the voltage detector, and an estimation process to estimate the condition of the electric storage device based on the distinctive point detected in the distinctive point detection process. The distinctive point is a point at which a variation in voltage per unit remaining capacity or per unit time of the electric storage device during charge or discharge is a local maximum value.

Condition estimation device and method of estimating condition

A condition estimation device includes a voltage measurement circuit, memory, and a controller. The voltage measurement circuit measures an open circuit voltage (OCV) of an electric storage device. The memory is configured to store first information on a correlation between a positive electrode potential and an electric storage capacity and second information on a correlation between a negative electrode potential and an electric storage capacity. The controller is configured to: measure an OCV under charge or discharge; calculate an electric storage capacity of the electric storage device having the OCV equal to a reference voltage; correct at least one of the first information and the second information such that a potential difference at the calculated capacity is equal to the reference voltage; and generate an OCV characteristic based on the first and the second information after the at least one of the first and the second information is corrected.

Growing community of inventors

Kyoto, Japan

Kenichi Sejima