JP2017003286A - Battery management unit and battery management method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery management unit capable of changing calculation method of battery remaining amount depending on the situation.SOLUTION: The battery management unit includes: an acquisition section that acquires a status of a vehicle mounted with a battery; and a control unit that determines the method of calculation; i.e. the battery remaining amount on the battery should be calculated in a first calculation method or a second calculation method in which the calculation amount is smaller than that in the first calculation method based on the state of the vehicle acquired by the acquisition section.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a battery management device and a battery management method.

A vehicle (secondary battery) is mounted as an energy source for driving in a vehicle such as a hybrid vehicle or an electric vehicle. In order to grasp the remaining travel distance of the automobile, estimation of a battery remaining amount (SOC: State of Charge) of a battery mounted on the automobile is performed.

JP 2009-005458 A Special table 2013-521556 gazette International Publication No. 2012/157786 JP 2011-101573 A JP 2013-192327 A JP 2001-174551 A JP 2012-054168 A JP 2006-020401 A JP 2010-210457 A

  By appropriately charging and discharging according to the remaining amount of the battery, etc., it is possible to suppress the deterioration of the battery and extend the life of the battery. Therefore, it is required to estimate the battery remaining amount of the battery with high accuracy. In addition, by accurately estimating the remaining battery level, it is possible to suppress an unexpected stop of the automobile due to a shortage of the remaining battery level.

  In order to accurately estimate the remaining battery level (SOC), high-precision estimation logic with a large amount of calculation is used. A battery mounted on an automobile includes a plurality of cells. The remaining battery level is calculated for each cell. Therefore, the amount of calculation is enormous in order to estimate the remaining battery level with high accuracy. When the amount of computation becomes enormous, computation by hardware is used to speed up the processing. When hardware is used for computation, there is a problem that power consumption increases. In addition, as a calculation method with a small amount of calculation, there is a method for estimating a battery remaining amount by time integration of a current value. However, with this method, it is difficult to calculate the battery remaining amount with high accuracy.

  An object of this invention is to provide the battery management apparatus which changes the calculation method of a battery remaining charge according to a condition.

The present invention employs the following means in order to solve the above problems.
That is, the first aspect of the present invention is
An acquisition unit for acquiring a state of a vehicle equipped with a battery;
Whether the battery remaining amount of the battery is calculated by the first calculation method or by the second calculation method with a smaller calculation amount than the first calculation method based on the state of the vehicle acquired by the acquisition unit A control unit for determining
It is a battery management apparatus provided with.
According to the first aspect, the battery remaining amount calculation method is changed according to the state of the vehicle.

The second aspect of the present invention further includes:
A circuit unit for calculating a battery remaining amount of the battery;
The circuit unit calculates a remaining battery level of the battery in the first calculation method,
The said control part is a battery management apparatus which calculates the battery remaining amount of the said battery with a said 2nd calculation method.
According to the second aspect, a calculation with a large calculation amount is performed in the circuit unit, and a calculation with a small calculation amount is performed in the control unit.

The third aspect of the present invention further includes
A storage unit for storing a battery remaining amount of the battery calculated by the circuit unit or the control unit;
The control unit calculates the remaining battery level of the battery using the first calculation method based on the state of the vehicle and the remaining battery level of the battery stored in the storage unit, or the second calculation method. It is a battery management apparatus which determines whether it calculates by.
According to the third aspect, the method for calculating the remaining battery level is determined based on the state of the vehicle and the remaining battery level of the battery.

The fourth aspect of the present invention further includes:
The state of the vehicle includes a torque of a motor that the vehicle has,
The control unit is a battery management device that calculates a current value of the battery based on the torque of the motor and calculates a remaining battery level of the battery based on the current value.
According to the fourth aspect, when the sensor that detects the state of the battery is out of order, the remaining battery level of the battery is calculated based on the current value of the battery based on the torque of the motor of the vehicle.

According to a fifth aspect of the present invention,
A storage unit for storing the remaining battery capacity of the battery;
Based on the remaining battery level of the battery stored in the storage unit, the remaining battery level of the battery is calculated by a first calculation method, or by a second calculation method having a smaller calculation amount than the first method. A control unit for determining whether to calculate,
It is a battery management apparatus provided with.
According to the fifth aspect, the battery remaining amount calculation method is determined based on the battery remaining amount.

  ADVANTAGE OF THE INVENTION According to this invention, the battery management apparatus which changes the calculation method of battery remaining charge according to a condition can be provided.

FIG. 1 is a diagram illustrating a configuration example of a system according to the embodiment. FIG. 2 is a diagram illustrating a configuration example of the battery management apparatus. FIG. 3 is a diagram illustrating an example of an operation flow of the operation example 1 of the battery management measure. FIG. 4 is a diagram illustrating an example of an operation flow of the operation example 2 of the battery management measure. FIG. 5 is a diagram illustrating an example of an operation flow of the operation example 3 of the battery management measure. FIG. 6 is a diagram illustrating an example of an operation flow of the operation example 3 of the battery management measure. FIG. 7 is a diagram illustrating an example of functional blocks in the circuit unit 43.

  Hereinafter, a system according to the present invention will be described with reference to the drawings. The configuration of the embodiment is an exemplification, and the present invention is not limited to the configuration of the disclosed embodiment.

Embodiment
FIG. 1 is a diagram illustrating a configuration example of a system according to the present embodiment. The system 1 of this embodiment includes a battery 10, a sensor 20, a vehicle state detection unit 30, and a battery management device 40. The system 1 of this embodiment is incorporated in a vehicle such as an electric vehicle, and the battery 10 is used as an energy source for driving the vehicle.

  The battery 10 is used as an energy source for driving an automobile on which the system 1 is mounted. The battery 10 has a plurality of cells. A sensor 20 is attached to the battery 10.

  The sensor 20 is a detection unit that detects the state of the battery 10. The sensor 20 includes a current sensor, a voltage sensor, a temperature sensor, and the like. The voltage sensor, current sensor, and temperature sensor measure the voltage, current, and temperature of the battery 10, respectively. The sensor 20 is provided for each cell of the battery 10. The detection result by the sensor 20 is acquired by the battery management device 40. The sensor 20 measures the battery state of the battery 10 at a predetermined cycle. The battery state is acquired by the battery management device 40 together with time information indicating the time when the battery state is measured.

  The vehicle state detection unit 30 detects the state of the automobile (vehicle) on which the system 1 is mounted. The state of the automobile (vehicle state) includes the mode of the automobile. The modes of the automobile include a traveling mode and a non-driving mode. The travel mode is a mode in a state where the automobile is traveling. The state where the automobile is traveling may include a state where the automobile is temporarily stopped. The non-running mode is a state in which the vehicle is not running, such as being charged or being IG (Ignition) OFF. Further, a state in which a key for operating the vehicle from the vehicle is removed may be set as a non-traveling mode. Whether or not charging is in progress is determined, for example, by whether or not a charging plug is connected to the vehicle. The vehicle state detection unit 30 detects whether the vehicle is in a travel mode or a non-travel mode. The vehicle state detected by the vehicle state detection unit 30 is acquired by the battery management device 40. Moreover, the vehicle state detection part 30 can detect the torque of the motor mounted in a vehicle. The motor is a motor for driving the vehicle. Other information may be included in the vehicle state.

  The battery management device 40 acquires the state of the battery 10 from the sensor 20 and the vehicle state from the vehicle state detection unit 30. The battery management device 40 calculates the remaining battery level (SOC) of the battery 10 based on the state of the battery 10, the state of the vehicle, and the like. The remaining battery level (SOC) is expressed as 100% when the battery 10 is fully charged.

  FIG. 2 is a diagram illustrating a configuration example of the battery management apparatus. The battery management device 40 includes a control unit 41, a storage unit 42, a circuit unit 43, and an acquisition unit 44.

The control unit 41 controls the battery management device 40. The control unit 41 calculates the battery remaining amount by a program or the like based on the vehicle state or the like, or causes the circuit unit 43 to calculate the battery remaining amount with high accuracy. The control unit 41 includes a CPU (Central Processing Unit), a ROM
(Read Only Memory), RAM (Random Access Memory), and the like. The calculation of the remaining battery level by the control unit 41 is also referred to as simple calculation. The simple calculation is an example of a second calculation method. The calculation result of the remaining battery level by the simple calculation is lower in accuracy than the calculation result of the remaining battery level by the circuit unit 43. The calculation of the remaining battery level by the control unit 41 is an example of calculation by software. The control unit 41 may be separated into a control unit that controls the battery management device 40 and a calculation unit that performs calculation.

The storage unit 42 stores various data used in the control unit 41, various programs, various tables, a battery state acquired from the sensor 20, a vehicle state acquired from the vehicle state detection unit 30, an estimated battery remaining amount (SOC), and the like. Store. The storage unit 42 is, for example, an EPROM (Erasable Programmable ROM), a hard disk drive (HDD, Hard Disk Drive), or a solid state drive (SSD). The storage unit 42 can include a removable medium, that is, a portable recording medium. The removable media is, for example, a USB (Universal Serial Bus) memory or a disc recording medium such as a CD (Compact Disc) or a DVD (Digital Versatile Disc).

The circuit unit 43 is a circuit (hardware) that calculates the remaining battery level with high accuracy. The circuit unit 43 is realized by an IC (Integrated Circuit) such as an FPGA (Field-Programmable Gate Array). The circuit unit 43 may include a plurality of ICs. When the circuit unit 43 includes a plurality of ICs, computation can be performed in parallel. By performing a parallel operation, the operation is speeded up. The calculation of the remaining battery level by the circuit unit 43 is also referred to as a large-scale calculation. Large-scale computation is an example of a first computation method. The circuit unit 43 may calculate SOH (State of Health) indicating the health level (deterioration state) of the battery 10. The calculation by the circuit unit 43 consumes more power than the calculation by the control unit 41. The calculation of the remaining battery level by the circuit unit 43 is an example of calculation by hardware.

  The acquisition unit 44 acquires the battery state of the battery 10 detected by the sensor 20 from the sensor 20. The acquisition unit 44 stores the acquired battery state of the battery 10 in the storage unit 42. The acquisition unit 44 acquires the vehicle state detected by the vehicle state detection unit 30 from the vehicle state detection unit 30. The acquisition unit 44 stores the acquired vehicle state in the storage unit 42. The acquisition unit 44 has a communication interface with the sensor 20, the vehicle state detection unit 30, and the like.

(Operation example 1)
FIG. 3 is a diagram illustrating an example of an operation flow of the operation example 1 of the battery management measure.

  In S101, the control unit 41 of the battery management device 40 confirms the mode of the automobile (vehicle) on which the system 1 including the battery management device 40 is mounted. The control unit 41 acquires the vehicle state detected by the vehicle state detection unit 30 via the acquisition unit 44. The control unit 41 stores the acquired vehicle state in the storage unit 42. The vehicle state includes vehicle mode information. The modes of the vehicle include a travel mode and a non-travel mode. If the vehicle mode is the travel mode (S101; YES), the process proceeds to step S102. If the vehicle mode is the non-running mode (S101; NO), the process proceeds to step S103.

In S <b> 102, the control unit 41 uses the circuit unit 43 to perform a large-scale calculation. When the vehicle state is the traveling mode, since the changes in the current, voltage, and SOC of the battery 10 are large, it is desirable to accurately calculate the remaining battery level (SOC). The control unit 41 acquires the battery state of the battery 10 from the sensor 20 via the acquisition unit 44 together with time information indicating the time when the battery state is measured. The battery state of the battery 10 is detected by the sensor 20. The sensor 20 detects voltage, current, and temperature as the battery state for each cell of the battery 10. The control unit 41 stores the acquired battery state in the storage unit 42 together with time information. The control unit 41 performs a filtering process such as calculating a time moving average on the acquired battery state, and transmits it to the circuit unit 43 together with time information. Based on the battery information (voltage, current, temperature) and time information received from the control unit 41, the remaining battery level (SOC) is calculated for each cell of the battery 10. The calculation of the SOC in the circuit unit 43 will be described later. The circuit unit 43 transmits the calculated SOC to the control unit 41. When receiving the SOC from the circuit unit 43, the control unit 41 stores the SOC in the storage unit 42 together with time information. Further, the control unit 41 calculates Win indicating power that may be input to the battery 10 and Wout indicating power that may be output from the battery 10 based on the SOC. The SOC, Win, and Wout are calculated for each cell.

  In S <b> 103, the control unit 41 performs a simple calculation without using the circuit unit 43. The control unit 41 acquires the battery state of the battery 10 from the sensor 20 via the acquisition unit 44 together with time information indicating the time when the battery state is measured. In addition, the control unit 41 acquires the SOC stored in the storage unit 42. The control unit 41 calculates the SOC for each cell by integrating the acquired current for each cell of the battery 10 over time. The simple calculation in the control unit 41 will be described later. The control unit 41 stores the calculated SOC in the storage unit 42 together with time information. Further, the control unit 41 calculates Win indicating power that may be input to the battery 10 and Wout indicating power that may be output from the battery 10 based on the calculated SOC.

  When the vehicle state is the non-running mode, the remaining amount of battery (SOC) can be easily achieved because changes in current, voltage, and SOC are small. According to the above operation flow, the SOC can be calculated by a simple calculation with low power consumption in the non-running mode in which the estimation of the SOC is easy.

(Operation example 2)
FIG. 4 is a diagram illustrating an example of an operation flow of the operation example 2 of the battery management measure.

  In S201, the control unit 41 of the battery management device 40 confirms the battery remaining amount (SOC) of the battery 10 calculated last. The control unit 41 extracts the last calculated SOC from the storage unit 42. When the extracted SOC is 20% or less or 80% or more (S201; NO), the process proceeds to step S202. If the extracted SOC is larger than 20% and smaller than 80% (S201; YES), the process proceeds to step S203. Here, when the SOC of all the cells of the battery 10 is larger than 20% and smaller than 80%, the determination in S201 is YES. When the SOC of any cell of the battery 10 is 20% or less or 80% or more, the determination in S201 is NO.

  In S <b> 202, the control unit 41 uses the circuit unit 43 to perform a large-scale calculation. When the SOC is 20% or less, it is required to handle the battery 10 so that the battery 10 is not overdischarged. Further, when the SOC is 80% or more, it is required to handle the battery 10 so that the battery 10 is not overcharged. That is, it is required to change the input and output to the battery 10 according to the SOC. Further, overdischarge and overcharge are not preferable because the battery 10 may deteriorate. Therefore, when the SOC is 20% or less, or when the SOC is 80% or more, it is required to accurately calculate the SOC. The large-scale calculation in S202 is the same as the large-scale calculation in S102 of FIG.

  In S <b> 203, the control unit 41 performs a simple calculation without using the circuit unit 43. When the SOC is larger than 20% and smaller than 80%, the risk of overdischarge and overcharge of the battery 10 is small. That is, the risk of deterioration of the battery 10 due to overdischarge and overcharge of the battery 10 is small. Therefore, in this case, the control unit 41 can suppress the power consumption of the battery management apparatus 10 by performing a simple calculation. The large-scale calculation in S203 is the same as the simple calculation in S103 of FIG.

(Operation example 3)
FIG. 5 is a diagram illustrating an example of an operation flow of the operation example 3 of the battery management measure.

  In S301, the control unit 41 of the battery management device 40 checks the mode of the automobile (vehicle) in which the system 1 including the battery management device 40 is mounted. The control unit 41 acquires the vehicle state detected by the vehicle state detection unit 30 via the acquisition unit 44. The control unit 41 stores the acquired vehicle state in the storage unit 42. The vehicle state includes vehicle mode information. The vehicle mode is a travel mode or a non-travel mode. If the vehicle mode is the travel mode (S301; YES), the process proceeds to step S302. If the vehicle mode is the non-traveling mode (S301; NO), the process proceeds to step S303.

  In S <b> 302, the control unit 41 of the battery management device 40 confirms the battery remaining amount (SOC) of the battery 10 calculated last. The control unit 41 extracts the last calculated SOC from the storage unit 42. When the extracted SOC is 20% or less (S302; NO), the process proceeds to step S304. If the extracted SOC is greater than 20% (S302; YES), the process proceeds to step S305. Here, when the SOC of all the cells of the battery 10 is greater than 20%, the determination in S302 is YES. When the SOC of any cell of the battery 10 is 20% or less, the determination in S302 is NO.

  In S303, the control unit 41 of the battery management device 40 checks the battery remaining amount (SOC) of the battery 10 calculated last. The control unit 41 extracts the last calculated SOC from the storage unit 42. When the extracted SOC is 80% or more (S303; NO), the process proceeds to step S304. If the extracted SOC is smaller than 80% (S303; YES), the process proceeds to step S305. Here, when the SOC of all the cells of the battery 10 is smaller than 80%, the determination in S303 is YES. When the SOC of any cell of the battery 10 is 80% or more, the determination in S303 is NO.

  In S <b> 304, the control unit 41 uses the circuit unit 43 to perform a large-scale calculation. This is because when the vehicle state is the traveling mode and the SOC is 20% or less, electric power is consumed during traveling and there is a risk of overdischarge. Moreover, it is because there exists a possibility of an overcharge during charge, when a vehicle state is a non-running mode and SOC is 80% or more. The large-scale calculation in S304 is the same as the large-scale calculation in S102 of FIG.

  In S <b> 305, the control unit 41 performs simple calculation without using the circuit unit 43. When the vehicle state is the traveling mode and the SOC is larger than 20%, the risk of overdischarge of the battery 10 is small. Further, when the vehicle state is the non-running mode and the SOC is less than 80%, the risk of overcharging of the battery 10 is small. Therefore, in these cases, the control unit 41 can suppress the power consumption of the battery management apparatus 10 by performing a simple calculation. The large-scale calculation in S305 is the same as the simple calculation in S103 of FIG.

  When the possibility of overcharge and overdischarge is high according to the above operation flow, the deterioration of the battery 10 is suppressed by obtaining the SOC by large-scale calculation with higher accuracy, and there is a possibility of overcharge and overdischarge. When it is low, the power consumption can be reduced by obtaining the SOC by a simple calculation.

(Operation example 4)
FIG. 6 is a diagram illustrating an example of an operation flow of the operation example 3 of the battery management measure.

In S <b> 301, the control unit 41 of the battery management device 40 determines whether or not the sensor 20 that detects the battery state of the battery 10 has failed. The control unit 41 determines that the sensor 20 is out of order when any of current, voltage, and temperature acquired from the sensor 20 via the acquisition unit 44 exceeds an assumed value range. . Moreover, the control part 41 may determine with it being out of order, when the value of any one of an electric current, a voltage, and temperature is the same value for the predetermined time. The control unit 41 may determine the failure of the sensor 20 by another method. If it is determined that the sensor 20 has not failed (S401; NO), the process proceeds to step S402. If it is determined that the sensor 20 has failed (S401; YES), the process proceeds to step S403.

  In S <b> 402, the control unit 41 uses the circuit unit 43 to perform a large-scale calculation. The control unit 41 acquires the battery state of the battery 10 from the sensor 20 via the acquisition unit 44 and performs large-scale calculation. The large-scale calculation in S302 is the same as the large-scale calculation in S102 of FIG.

  In S <b> 403, the control unit 41 acquires the motor torque from the vehicle state detection unit 30 via the acquisition unit 44. The control unit 41 calculates a current value output from the battery 10 based on the acquired motor torque.

  In S404, the control unit 41 performs a simple calculation. In addition, the control unit 41 acquires the SOC stored in the storage unit 42. The control unit 41 calculates the SOC by integrating the current value calculated in S403 over time. The control unit 41 stores the calculated SOC in the storage unit 42 together with time information. Further, the control unit 41 calculates Win indicating power that may be input to the battery 10 and Wout indicating power that may be output from the battery 10 based on the calculated SOC. The SOC, Win, and Wout are calculated for each cell.

Even if the sensor 20 fails due to the above-described operation flow, the SOC can be obtained by a simple calculation by calculating the current value from the motor torque. Further, if the large-scale calculation is performed with the sensor 20 in failure, the calculated SOC becomes inaccurate. If the battery 10 is used based on the inaccurate SOC, the battery 10 may be deteriorated or damaged. Therefore, large-scale calculations are not performed when the sensor 20 fails.
The above operation examples can be combined as much as possible.

(Example of large-scale calculation by circuit)
The circuit unit 43 calculates the SOC using, for example, an equivalent circuit model of the battery and a Kalman filter. The circuit unit 43 is not limited to the example shown here.

  FIG. 7 is a diagram illustrating an example of functional blocks in the circuit unit 43. 7 includes a current integrating unit 51, a no-load voltage estimating unit 52, an adding unit 53, a subtracting unit 54, a polarization voltage calculating unit 55, and an internal state correcting unit 56. Each value of the current, voltage, and temperature of the battery 10 is input to the circuit unit 43 as time series data by the control unit 41.

  The current integration unit 51 integrates the measured current value of the battery 10 with time to calculate an estimated SOC value. Current integrating unit 51 corrects the estimated SOC value using the correction value provided by internal state correcting unit 56. The calculated SOC estimated value is output to the no-load voltage estimating unit 52. In addition, current integrating unit 51 outputs the SOC estimated value to control unit 41.

The no-load voltage estimation unit 52 obtains the OCV for the estimated SOC value from the OCV (Open Circuit Voltage) characteristic (OCV-SOC characteristic) with respect to the measured temperature and the remaining battery level (SOC). OCV is the no-load voltage of the battery. Usually, the voltage measured at the battery is not a no-load voltage. The no-load voltage estimation unit 52 has OCV-SOC characteristics in advance. The OCV-SOC characteristic indicates the relationship between OCV and SOC. Required OCV
Is output to the adder 54.

  The polarization voltage estimation unit 53 estimates the polarization voltage of the battery based on the measured temperature, the measured current value, and the correction value by the internal state correction unit 56. Polarization refers to an action deviating from the OCV such as resistance polarization (battery internal resistance × energization current). The polarization voltage is a voltage at which the measurement voltage deviates from the OCV. That is, the sum of the no-load voltage and the polarization voltage becomes the measured battery voltage (measured voltage). The estimated polarization voltage is output to the adding unit 54.

  The adder 54 adds the OCV output from the no-load voltage estimation unit 52 and the polarization voltage output from the polarization voltage calculation unit 53 to calculate a measured voltage estimated value. The measured voltage estimated value is output to the subtracting unit 55.

  The subtractor 55 calculates a difference between the input voltage value (measured value) of the battery 10 and the measured voltage estimated value output from the adder 54. The calculated difference is output to the internal state correction unit 56.

  Based on the measured battery current value, the difference between the measured battery voltage value and the measured voltage estimated value, the measured temperature, etc., the internal state correcting unit 56 corrects the correction value and polarization voltage for the current integrating unit 51. A correction value for the calculation unit 55 is calculated. The correction value is a value that makes the difference between the measured battery voltage value and the measured voltage estimated value smaller. Since feedback is applied by the correction value by the internal state correction unit 56, the calculation in the current integration unit 51 and the polarization voltage calculation unit 55 becomes more accurate.

  For example, the circuit unit 43 may output SOC (SOC estimated value) to the control unit 43 when the difference between the measured battery voltage value and the measured voltage estimated value is less than a predetermined value.

  The amount of large-scale calculation by the circuit unit 43 is larger than the amount of simple calculation by the control unit 41. Further, the power consumption by the large-scale calculation by the circuit unit 43 is larger than the power consumption by the simple calculation by the control unit 41. Large-scale calculation in the circuit unit 43 may be performed by the control unit 41.

(Example of simple calculation by the control unit)
The control unit 41 sets the initial value of the SOC from the OCV-SOC characteristic, and updates the SOC by integrating the current obtained as the battery state over time. The OCV-SOC characteristic is stored in the storage unit 42. In addition, when the SOC has been calculated in the past, the control unit 41 extracts the last calculated SOC from the storage unit 42 and updates the SOC by integrating the current obtained as the battery state over time. May be. In this calculation method, power consumption is small, but errors in the current value from the sensor 20 accumulate, so the calculated SOC may be inaccurate compared to large-scale calculations.

(Example of parallel operation in the circuit section)
In the circuit unit 43, the number of cells of the battery 10 is equal to the number of cells such as FPGAs, so that the SOC can be calculated at once. However, it is not desirable to prepare an IC such as an FPGA for the number of cells of the battery 10 because the circuit scale increases and the power consumption increases.

  Here, a description will be given of the case where the battery 10 includes 16 cells, and the series-parallel operation is performed by the four ICs included in the circuit unit 43. In the cell of the battery 10, no. 1 to No. Assume that numbers up to 16 are assigned. In addition, the IC has no. 1 to No. Suppose numbers up to 4 are assigned.

  First, the control unit 41 sets the circuit unit 43 to No. 1 to No. Data on the battery status of up to 4 cells is transmitted in series. The circuit unit 43 is No. 1 to No. No. 4 to No. 4, respectively. 1 to No. Input battery status data for up to 4 cells. Each IC of the circuit unit 43 calculates the SOC of each cell. The circuit unit 43 displays the calculated No. 1 to No. The SOCs of up to four cells are arranged in series and transmitted to the control unit 41. No. 5 to No. No. 8 cells, no. 9 to No. Up to 12 cells, no. 13 to No. Similarly, for the cells up to 16, the circuit unit 43 No. 1 to No. The SOC is calculated using up to four ICs.

  By doing in this way, SOC about more cells can be calculated with less IC. In this example, compared to the case where 16 ICs are prepared for 16 cells and the parallel operation is performed, the circuit scale can be reduced to ¼, and the component cost and the design / evaluation cost are reduced. it can. In addition, since the amount of data transmitted at a time between the control unit 41 and the circuit unit 43 becomes ¼, the communication line capacity between the control unit 41 and the circuit unit 43 can be further reduced.

(Operation and effect of the embodiment)
The battery management device 10 determines whether to calculate the battery remaining amount by large-scale calculation or simple calculation based on the vehicle state and the battery state. The battery management device 10 can reduce the power consumption in the battery management device 10 by calculating the remaining amount of the battery by simple calculation when the risk of overdischarge and overcharge of the battery 10 is small. The battery management device 10 can suppress deterioration of the battery 10 by calculating the remaining battery amount with high accuracy by large-scale calculation when the risk of overdischarge or overcharge of the battery 10 is large.

DESCRIPTION OF SYMBOLS 1 System 10 Battery 20 Sensor 30 Vehicle state detection part 40 Battery management apparatus 41 Control part 42 Memory | storage part 43 Circuit part 44 Acquisition part 51 Current integration part 52 No-load voltage estimation part 53 Polarization voltage calculation part 54 Addition part 55 Subtraction part 56 Inside Condition correction unit

Claims (6)

An acquisition unit for acquiring a state of a vehicle equipped with a battery;
Whether the battery remaining amount of the battery is calculated by the first calculation method or by the second calculation method with a smaller calculation amount than the first calculation method based on the state of the vehicle acquired by the acquisition unit A control unit for determining
A battery management device comprising: A circuit unit for calculating a battery remaining amount of the battery;
The circuit unit calculates a remaining battery level of the battery in the first calculation method,
The battery management device according to claim 1, wherein the control unit calculates a remaining battery level of the battery by the second calculation method. A storage unit for storing a battery remaining amount of the battery calculated by the circuit unit or the control unit;
The control unit calculates the remaining battery level of the battery using the first calculation method based on the state of the vehicle and the remaining battery level of the battery stored in the storage unit, or the second calculation method. The battery management device according to claim 2, wherein it is determined whether or not to perform calculation. The state of the vehicle includes a torque of a motor that the vehicle has,
4. The control unit according to claim 1, wherein the control unit calculates a current value of the battery based on the torque of the motor and calculates a remaining battery level of the battery based on the current value. 5. Battery management device. A storage unit for storing the remaining battery capacity of the battery;
Based on the remaining battery level of the battery stored in the storage unit, the remaining battery level of the battery is calculated by a first calculation method, or by a second calculation method having a smaller calculation amount than the first method. A control unit for determining whether to calculate,
A battery management device comprising: Based on the state of the vehicle, the remaining amount of the battery is calculated by the first calculation method or by the second calculation method with a smaller calculation amount than the first calculation method. A battery management method for determining whether to calculate.

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