Abstract: The present invention pertains to the detection of the state of charge of a battery, whereby the complex impedance in the diffusion region of the battery is used. An arithmetic device such as a computer determines the slope of the complex impedance at least two different frequencies in the diffusion region of a rechargeable battery when a straight-line approximation has been made. The state of charge of the rechargeable battery is detected by using the slope that has been determined, and the relationship between the state of charge and slopes that have been stored in advance in a storage means.

Abstract: A method includes discharging an assembled battery (10) formed of a plurality of batteries until a state of charge (SOC) of the assembled battery becomes smaller or equal to a lower limit of a predetermined normal use range used in charge and discharge control of the assembled battery, measuring the discharge capacity of each of a plurality of battery blocks in the discharge of the assembled battery, the plurality of batteries being divided into the plurality of battery blocks, calculating the capacity difference in the discharge capacity among the plurality of battery blocks, and determining the remaining life of the battery block or the assembled battery based on the calculated capacity difference.

Abstract: This device and method use the complex impedance of a rechargeable battery to detect the state of the rechargeable battery. A computer determines the slope of the complex impedance at least two different frequencies in a diffusion region of the rechargeable battery when a straight-line approximation has been made, and compares the slope with a threshold value. If the slope is greater than or equal to the threshold value, the computer determines that the battery has a normal capacity balance, and if the slope is less than the threshold value, the computer determines that the battery has an abnormal unbalanced capacity. Furthermore, if the magnitude of an imaginary axis component of the complex impedance in the diffusion region of the rechargeable battery is greater than the threshold battery, the computer determines that the battery has an abnormal capacity balance, and if said magnitude is less than or equal to the threshold value, the computer determines that the battery has a normal capacity balance.

Abstract: A method includes discharging an assembled battery (10) formed of a plurality of batteries until a state of charge (SOC) of the assembled battery becomes smaller or equal to a lower limit of a predetermined normal use range used in charge and discharge control of the assembled battery, measuring the discharge capacity of each of a plurality of battery blocks in the discharge of the assembled battery, the plurality of batteries being divided into the plurality of battery blocks, calculating the capacity difference in the discharge capacity among the plurality of battery blocks, and determining the remaining life of the battery block or the assembled battery based on the calculated capacity difference.

Abstract: The present invention pertains to the detection of the state of charge of a battery, whereby the complex impedance in the diffusion region of the battery is used. An arithmetic device such as a computer determines the slope of the complex impedance at least two different frequencies in the diffusion region of a rechargeable battery when a straight-line approximation has been made. The state of charge of the rechargeable battery is detected by using the slope that has been determined, and the relationship between the state of charge and slopes that have been stored in advance in a storage means.

Abstract: This device and method use the complex impedance of a rechargeable battery to detect the state of the rechargeable battery. A computer determines the slope of the complex impedance at least two different frequencies in a diffusion region of the rechargeable battery when a straight-line approximation has been made, and compares the slope with a threshold value. If the slope is greater than or equal to the threshold value, the computer determines that the battery has a normal capacity balance, and if the slope is less than the threshold value, the computer determines that the battery has an abnormal unbalanced capacity. Furthermore, if the magnitude of an imaginary axis component of the complex impedance in the diffusion region of the rechargeable battery is greater than the threshold battery, the computer determines that the battery has an abnormal capacity balance, and if said magnitude is less than or equal to the threshold value, the computer determines that the battery has a normal capacity balance.

Abstract: Provided is a battery pack producing method and a battery pack capable of suppressing defects such as overcharging or overdischarging in one or more of the used secondary batteries constituting a battery pack, and sufficiently exhibiting the performance of the used secondary batteries of the battery pack. This method includes an obtaining process for obtaining each full charge capacity of the used secondary batteries, a selecting process for selecting one or more used secondary batteries having similar full charge capacities from the used secondary batteries whose full charge capacities have been obtained, and an assembling process for assembling the selected secondary batteries.

Abstract: A device which judges a change of a capacity balance between a cathode and an anode of a secondary battery in a non-destructive manner is provided. The secondary battery has one of the capacities of the cathode and the anode greater than the other capacity. A battery ECU calculates an internal resistance (DCIR) of the secondary battery based on a current and a voltage of the secondary battery. When the calculated internal resistance (DCIR) is higher than the initial state in a low SOC region or a high SOC region, the battery ECU judges that the capacity balance between the cathode and the anode of the secondary battery has changed.

Abstract: Provided are a battery pack manufacturing method, which can prevent a drawback where some of the used secondary batteries constituting a battery pack prematurely come to an end and which can suppress the enlargement of the temporary voltage difference between a used secondary battery at a charging/discharging time (especially in a low-temperature circumstance), and a battery pack. The battery pack manufacturing method includes an acquiring step of acquiring the individual internal resistances of used secondary batteries collected from the market, a selection step of selecting a plurality of the used secondary batteries having the internal resistances close to each other from a group of the used secondary batteries whose internal resistances have been acquired, and an assembling step of combining the used secondary batteries selected, to constitute the battery pack.

Abstract: A method of reusing a rechargeable battery includes collecting from users assembled batteries formed by rechargeable batteries, each holding initial individual information including at least a manufacturing date and an initial weight of the rechargeable battery. The collected assembled batteries are dismantled into rechargeable batteries, each holding the individual information. The rechargeable batteries of the dismantled assembled batteries are classified into groups based on the initial individual information of the rechargeable batteries and individual information of the plurality of rechargeable batteries obtained after the dismantling. A regenerated assembled battery is rebuilt reusing rechargeable batteries that have been classified into the same group.

Abstract: A two-dimensional map for calculating an SOC of a secondary battery is corrected. A battery ECU obtains a voltage index of a secondary battery. The voltage index is, for example, a no-load voltage of the secondary battery. When an amount of change of the calculated no-load voltage from an initial state falls outside a predefined range, the battery ECU corrects the two-dimensional map of initial state which is stored in advance in a storage unit using data obtained by statistically processing a plurality of two-dimensional maps obtained from a plurality of vehicles.

Abstract: The invention provides a method of adjusting a battery pack capable of reducing a difference in charge level between a plurality of secondary batteries constituting the battery pack and capable of restraining an increase in battery voltage difference between the secondary batteries of the battery pack in association with the adjustment of the charge level. A method of adjusting a battery pack includes a first adjusting process for discharging all secondary batteries of a first battery group so that charge levels of the secondary batteries of the first battery group fall within a charge level range determined based on a charge level of a secondary battery of a second battery group and further a second adjusting process for discharging all the secondary batteries of the first and second battery groups by the same electric quantity respectively.

Abstract: A reconstituted battery pack producing method comprises an obtaining process for obtaining, by use of one of a first charged-state control device having ever controlled a charged state of a used battery pack when it was used before and a second charged-state control device arranged to control the charged state of the used battery pack as with the first charged-state control device, a reference-time charge amount charged in each used secondary battery constituting the used battery pack; a selecting process for selecting more than one of the used secondary batteries close to each other in the reference-time charge amount from a group of the used secondary batteries whose reference-time charge amounts have been obtained; and an assembling process for combining and assembling the selected used secondary batteries into a new reconstituted battery pack.

Abstract: A device which judges a change of a capacity balance between a cathode and an anode of a secondary battery in a non-destructive manner is provided. The secondary battery has one of the capacities of the cathode and the anode greater than the other capacity. A battery ECU calculates an internal resistance (DCIR) of the secondary battery based on a current and a voltage of the secondary battery. When the calculated internal resistance (DCIR) is higher than the initial state in a low SOC region or a high SOC region, the battery ECU judges that the capacity balance between the cathode and the anode of the secondary battery has changed.

Abstract: A two-dimensional map for calculating an SOC of a secondary battery is corrected. A battery ECU obtains a voltage index of a secondary battery. The voltage index is, for example, a no-load voltage of the secondary battery. When an amount of change of the calculated no-load voltage from an initial state falls outside a predefined range, the battery ECU corrects the two-dimensional map of initial state which is stored in advance in a storage unit using data obtained by statistically processing a plurality of two-dimensional maps obtained from a plurality of vehicles.

Abstract: A battery pack capable of sufficiently exhibiting performance of each secondary battery constituting the battery pack and its producing method are provided. The battery pack producing method of the invention comprises an obtaining process for obtaining a charge amount voltage curve C during charging and a charge amount voltage curve D during discharging, a selecting process for selecting more than one of the used secondary batteries close to each other in curves C and D from a group of the used secondary batteries whose curves C and D have been obtained, and an assembling process for combining the selected used secondary batteries to constitute the battery pack.