Sanyo Electric Co., Ltd.

Hiroya Murao

Yutaka Yamauchi

Kimihiko Furukawa

Keiji Kishimoto

Shigeto Tamezane

Mika Kirimoto

Yuri Kimura

Daiki Hamada

Kentaro Uemura

A power supply unit comprises a battery, current and voltage detecting portions, and a remaining capacity computing portion. The remaining capacity computing portion comprises a first computing portion computing a first open circuit terminal voltage based on current and voltage values from the current and voltage detecting portions, and computing a first remaining capacity based on the first open circuit terminal voltage, a second computing portion computing a second open circuit terminal voltage based on the current and voltage values, an ohmic resistance voltage drop and a polarization resistance voltage drop, and computing a second remaining capacity based on the second open circuit terminal voltage, a third computing portion calculating a third remaining capacity based on an integrated value by integrating the current, and a main computing portion computing a real remaining capacity of the battery based on the first and/or third remaining capacity, and the second remaining capacity.

Power supply unit, vehicle and storage battery unit equipped with power supply unit, and remaining capacity detecting method of battery

A battery system is provided with a plurality of battery units each including a battery module consisting of a plurality of battery cells, a unit control unit, and a connector, and controls the overall operation of the respective battery units in a main control unit. To the plurality of connectors of the battery units, an external unit can be selectively connected so that voltage adjustment for inhibiting voltage variations among the plurality of battery cells or the plurality of battery modules can be realized by using the external unit. The external unit is connected to the battery unit for which voltage adjustment is necessary on the basis of a voltage adjustment necessity determination.

Battery unit, electric vehicle, movable structure, power supply device, and battery control device

A battery ECU acquires open circuit voltages of a plurality of battery cells that are divided into a plurality of groups A, B, C using a plurality of detecting units, and calculates SOCs of the battery cells based on the open circuit voltages. Then, the battery ECU selects the group to which the battery cell having the largest SOC among the SOCs of the plurality of battery cells belongs, and selects the battery cell to be discharged in the selected group. A series circuit composed of a resistor and a switching element is connected in parallel with each battery cell. The battery ECU turns on the switching element corresponding to the selected battery cell. At this time, the battery cell is connected to the resistor, thus being discharged.

Equalization device, equalization processing program, battery system, electric vehicle and equalization processing method

An SOC of each battery cell is periodically detected, and an SOCmin and an SOCmax are determined. Battery cells having the SOCs larger than SOCmin+&#x3b1; are selectively discharged. After an elapse of a preset equalization processing time period, discharge of all the battery cells is stopped. The equalization processing time period is set based on a rate of change in the SOC of the battery cell subjected to discharge and a rate of change in the SOC of the battery cell not subjected to discharge such that a magnitude relationship between the SOC of the battery cell having the SOCmin and the SOC of another battery cell is not reversed.

Equalization device, battery system and electric vehicle including the same, equalization processing program, and equalization processing method

A state of charge optimizing device according to the present invention optimizes a state of charge of each of a plurality of cells which are connected in series to form an assembled battery, and conducts the optimization by discharging or charging a part or all of the plurality of cells so that the differences between the amount of charge after the optimization and the amount of charge in a predetermined state of charge become uniform.

State of charge optimizing device and assembled battery system including same

A state-of-charge equalizing device equalizes the state of charge of each of cells connected in series to form an assembled battery, and comprises charging/discharging circuits connected in parallel to the respective cells to discharge and/or charge the respective cells, voltage measurement circuits connected to the respective charging/discharging circuits to measure the voltages across the respective cells, and a control circuit. The control circuit comprises a unit calculating an equalization target voltage based on the measured voltages before the charge or discharge starts, a unit starting discharging/charging the cells having a voltage thereacross different from the target voltage, a unit correcting the target voltage to thereby calculate a corrected equalization target voltage for each of those cells based on the difference between the measured voltages before and at a certain time period after the charging/discharging, and a unit ending the discharging/charging when the measured voltage reaches the corrected target voltage.

Growing community of inventors

Hirakata, Japan

Hiroya Murao