Panasonic Ev Energy Co., Ltd.

Matsushita Electric Industrial Co., Ltd.

Norito Yamabe

Yusai Murakami

Tadao Kimura

Takao Yamamoto

Teruyoshi Egoshi

Masahiro Takada

Keiichi Minamiura

Kouta Togashi

Masayoshi Toyota

An abnormality of a current sensor or a voltage sensor is detected. An abnormality detecting section reads out a charging/discharging current I of a secondary battery detected by the current sensor and a battery voltage V of the secondary battery, calculates an estimated battery voltage Vs on the basis of an electromotive force E and an internal resistance r of the secondary battery, and judges the current sensor to be abnormal if the difference between the battery voltage V and the estimated battery voltage Vs is greater than a predetermined threshold and the charging/discharging current I exceeds a predetermined allowable range, and judges the voltage sensor to be abnormal if the difference is greater than the predetermined threshold and the charging/discharging current I is within the predetermined allowable range.

Abnormality detecting device, abnormality detecting method, and computer readable medium storing an abnormality detecting program

In a battery cooling device for cooling a battery with air from a cooling unit, such as a cooling fan, the air flow of the cooling unit is optimally controlled. A air flow control device calculates a calorific value of the battery based on an internal resistance of the battery and a charge/discharge current measured by a current measurement unit, calculates the difference as a differential temperature between battery temperature measured by a battery temperature measurement unit and ambient temperature measured by an ambient temperature measurement unit, and controls the air flow of the cooling fan on the basis of the calculated calorific value and the differential temperature.

Battery cooling device, air flow control device, and computer readable medium

In a battery cooling device for cooling a battery with cooling air from a cooling unit, such as a cooling fan, the cooling fan is not to be driven more than necessary. A cooling air flow control unit calculates a battery temperature change rate indicating an amount of change in battery temperature over a predetermined time based on the battery temperature, and if the calculated battery temperature change rate satisfies a predetermined suppression control condition, the cooling air flow of the cooling fan is suppressed regardless of whether or not the battery temperature is at or below a reference temperature.

Battery cooling device, battery cooling air flow control device, and computer readable medium

To provide a voltage measurement device for measuring a battery voltage of a secondary battery formed by serially connecting a plurality of battery blocks, which is able to calculate the battery voltage in block units even though a potential detection line is disconnected. Specifically, when the voltage detection unit fails to measure the battery voltage of the measurement target battery block by selecting potential detection lines connected to both terminals of the measurement target battery block, the switch control unit selects the potential detection lines connected to both terminals of the battery block group including a serially connected plurality of battery blocks including the measurement target battery block, then measures the integrated voltage of the battery block group, and measures the battery voltage of the measurement target battery block based on the measured integrated voltage.

Voltage measurement device and electric vehicle

A device for appropriately controlling capacitive variations between battery blocks. A voltage measurement section periodically measures a terminal voltage of each battery block by way of respective potential detection lines electrically connected to both terminals of the respective battery blocks. A discharge section effects electric discharge of each battery block by electrically connecting both terminals of a discharge element to both terminals of the respective battery blocks by way of the potential detection line. A discharge control section periodically computes an amount of variations in electromotive force of the battery blocks in accordance with respective terminal voltages measured by the voltage measurement section in parallel with measurement of the respective terminal voltages performed by the voltage measurement section, and commands the discharge section to effect electric discharge of a battery block exhibiting highest electromotive force when the amount of variations exceeds a first reference amount. Further, when the voltage measurement section measures a terminal voltage of the battery block being electrically discharged by the discharge section, the discharge control section commands the discharge section to stop electric discharge of the battery block being electrically discharged before the measurement is performed.

Apparatus for equalizing capacity of secondary battery, and discharge controller

Error in an electromotive force Ve of a secondary battery calculated on the basis of a polarized voltage Vp is reduced. A polarized voltage computing section acquires multiple data pairs of a current I flowing to the secondary battery and a terminal voltage V of the secondary battery with respect to the current I, calculates an integrated capacity Q by integrating the acquired current I over a predetermined period, computes the polarized voltage Vp of the secondary battery on the basis of the integrated capacity Q, a no-load voltage computing section computes a no-load voltage Von the basis of multiple data pairs, a subtracter computes the electromotive force Ve of the secondary battery by subtracting the polarized voltage Vp from the no-load voltage V, an electromotive force correcting section performs correction with respect to a presently computed electromotive force Ve so that a change amount between a previously computed electromotive force Veb and the presently computed electromotive force Ve does not exceed a predetermined limiting value Vt, and an SOC estimating section estimates the state of charge of the secondary battery on the basis of the post-correction electromotive force Ve'.

Electromotive force computing device and state of charge estimating device

An apparatus estimates charge/discharge electricity amount without being affected by current measurement error. Under specific selection conditions, a no-load voltage calculation part uses pairs of data consisting of current data I(n) and voltage data V(n) corresponding to the current data to calculate a no-load voltage Vas the voltage intercept at a current of zero in a straight-line approximation obtained by statistical processing such as regression analysis using a least squares method. If specific current conditions exist for a certain amount of time, an open circuit voltage calculation part calculates the terminal voltage of the secondary battery as the open circuit voltage V. An estimated charge/discharge electricity amount calculation part uses a preset change-in-voltage adjustment constant &#x394;V/adjustment coefficient K, change-in-electromotive-force constant Kand polarization voltage generation constant Kto calculate the estimated charge/discharge electricity amount &#x394;Qas a function of the change &#x394;Vin the no-load or open circuit voltage over a predetermined period of time.

Method and apparatus for estimating the charge/discharge electricity amount of secondary batteries

The present invention provides an apparatus that can estimate the charge/discharge electricity amount without being affected by current measurement error. If specific selection conditions are met, a no-load voltage calculation part () takes a plurality of pairs of data consisting of current data I(n) and voltage data V(n) corresponding to the current data and calculates a no-load voltage Vas the voltage intercept at a current of zero in a straight-line approximation obtained by statistical processing such as regression analysis using a least squares method with respect to the plurality of pairs of data. In addition, if specific current conditions continue to be met for a certain amount of time, an open circuit voltage calculation part () calculates the terminal voltage of the secondary battery as the open circuit voltage V. An estimated charge/discharge electricity amount calculation part () uses a preset change-in-voltage adjustment constant &#x394;V/adjustment coefficient K, change-in-electromotive-force constant Kand polarization voltage generation constant Kto calculate the estimated charge/discharge electricity amount &#x394;Qas a function of the change &#x394;Vin the no-load voltage or the open circuit voltage over a predetermined period of time.

Method and device for estimating charge/discharge electricity amount of secondary cell

The present invention provides an apparatus for correcting a voltage of a secondary battery, wherein accuracy in measurement of battery voltages between battery blocks in different voltage measurement systems. In a battery ECU (), the following components are disposed: a first voltage measuring part (-), a second voltage measuring part (-), a third voltage measuring part (-) and a fourth voltage measuring part (-) which are disposed in different voltage measurement systems so as to measure voltages of plural battery blocks; a representative voltage calculating part () for calculating representative voltages from battery voltages measured by the first to fourth voltage measuring parts; a voltage correction value calculating part () for calculating voltage correction values on the basis of the respective representative voltages; and a correction value reflecting part () for adding the voltage correction values to measured voltages of battery blocks in the respective corresponding voltage measurement systems.

Method and apparatus for correcting voltage of secondary battery, and method and apparatus for estimating state of charge of secondary battery

When a power switch portionis in an open state and a charge/discharge path of the secondary batteryis in a disconnected state, an electromotive force calculation portioncalculates a battery electromotive force Veq by subtracting a polarized voltage Vpol stored in a polarized voltage storage portionfrom an open-circuit voltage OCV measured by a voltage measurement portion. Based on the electromotive force, a state-of-charge estimation portionestimates a state of charge SOC. Thus, a polarized voltage to be considered for the estimation of SOC can be limited. The state of charge (SOC) of a secondary battery can be estimated with high accuracy and quickly.

Method and apparatus for estimating state of charge of secondary battery

There is provided a battery pack system with estimation accuracy of a remaining capacity of a secondary batter enhanced. A current accumulation coefficient correction sectioncalculates a correction amount &#x3b1; with respect to a current accumulation coefficient k in accordance with a battery electromotive force Veq from an electromotive force calculation section. A remaining capacity calculation sectionestimates a remaining capacity SOC by current accumulation, based on the current accumulation coefficient k calculated from a correction amount &#x3b1;, and a charging efficiency &#x3b7; based on a currently estimated remaining capacity calculated by a charging efficiency calculation section

Method and apparatus for estimating remaining capacity of secondary battery

There is provided a battery pack system that allows an output limit during short-time discharging and long-time discharging of a secondary battery, and limits the output appropriately upon request of a vehicle. An output limiting sectionis provided for changing a limit value of output electric power from the secondary battery when voltage data V (n) from a voltage measuring sectionreaches a predetermined discharging termination voltage. The output limiting sectionhas short-time output information (Pp) for allowing short-time discharging of the secondary battery and normal output information (Pn) for allowing long-time discharging of the secondary battery, and sets a first discharging termination voltage (V) during short-time discharging to be lower than a second discharging termination voltage (V) during long-time discharging.

Apparatus and method for controlling output of secondary battery, battery pack system, and electric vehicle

A method of detecting and resolving a memory effect capable of detecting the memory effect with ease and with high precision and resolving even when the vehicle is in motion is provided. A current in a secondary battery is detected, a variation &Dgr;SOC in a residual battery capacity for a predetermined time period is calculated according to at least current integration by multiplying the detected current by a predetermined charge efficiency (S ), a temperature of the secondary battery is detected and a variation &Dgr;V in a no-load voltage for the predetermined time period is calculated based on the detected current, and an internal resistance corresponding to the detected temperature and the SOC is calculated (S ). A ratio k of the variation in the no-load voltage to the variation in the residual battery capacity is calculated (S ). If the ratio exceeds a predetermined threshold value kst, then the battery is judged to have a memory effect (S ), and the usage range of the SOC is extended for a predetermined time period (S ) or the correction of the SOC using voltages is prohibited for a predetermined time period(S ).

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Toyohashi, Japan

Norito Yamabe