JP6389677B2 - Battery charge rate estimation device - Google Patents

Description

  The present invention relates to a battery charge rate estimation device for estimating a charge rate of a battery.

  For example, in various vehicles such as an electric vehicle (EV) that travels using an electric motor and a hybrid vehicle (HEV) that travels using both an engine and an electric motor, a lithium ion rechargeable battery is used as a power source for the electric motor. And rechargeable batteries such as nickel metal hydride batteries. An apparatus for estimating the charging rate of such a secondary battery (that is, the current storage amount with respect to the maximum capacity that can be stored in the battery) is disclosed in Patent Document 1, for example.

  The battery charging rate estimation device disclosed in Patent Document 1 calculates the current integration method charging rate SOCi from the integrated value of the charging / discharging current value of the battery and the charging rate SOC of the battery that is fed back, and the charging / discharging current value A current integration method variance Qi is obtained based on information on detection accuracy. In parallel with this, the charging / discharging current value and the terminal voltage value of the battery are applied to the battery equivalent circuit model, and the open-circuit voltage method charging rate SOCv is obtained from the estimated open-circuit voltage value. Based on the information regarding the detection accuracy of the voltage value V, the open circuit voltage method variance Qv is obtained. Then, an error of the current integration method charging rate SOCi is estimated from the difference between the current integration method charging rate SOCi and the open-circuit voltage method charging rate SOCv, the current integration method variance Qi and the open-circuit voltage method variance Qv. The charging rate of the battery is obtained from the legal charging rate SOCi.

JP 2012-149947 A

  Due to the characteristics of the secondary battery, for example, as shown in FIG. 7, when the energization is stopped after energizing the charging current I having the current value Ic, the secondary battery is generated by the electromotive force of the secondary battery. After the voltage v between both electrodes fluctuates to a voltage value Vc higher than the open circuit voltage value OCV (Open circuit voltage) which is the true output voltage value of the secondary battery, the voltage v gradually drops over several minutes to several hours and opens. It returns to the voltage value OCV. The same applies when a discharge current is applied.

  Therefore, for example, when the voltage v between both electrodes of the secondary battery changes toward the open circuit voltage value OCV after the energization of the charging current I having the current value Ic is stopped, the voltage between both electrodes of the secondary battery. When v is measured, a voltage value including an error is measured with respect to the open circuit voltage value OCV. And in the charge rate estimation apparatus mentioned above, although the voltage value which arises between terminals when charging / discharging electric current flows into the internal resistance of the battery which is a secondary battery is considered, it arises between terminals by the electromotive force of a battery. The above fluctuation of the voltage value is not taken into consideration, and therefore, an error that is not taken into consideration may be included in the measured open-circuit voltage value of the battery. Further, in the method of detecting the charging rate by the current integration method, for example, the offset error of the current sensor is also integrated. For these reasons, there is room for improvement in the detection accuracy of the battery charge rate in the conventional charge rate estimation apparatus described above.

  The present invention aims to solve this problem. That is, an object of the present invention is to provide a battery charge rate estimation device that can further improve the estimation accuracy of the charge rate.

The invention described in claim 1 is a battery charging rate estimation device for estimating a charging rate of a battery,
A voltage fluctuation amount signal output means for outputting a voltage fluctuation amount signal corresponding to a voltage fluctuation amount with respect to an open-circuit voltage value generated by a charging / discharging current flowing through the battery at a voltage between both electrodes of the battery; and both electrodes of the battery An open-circuit voltage value detecting means for detecting the open-circuit voltage value based on the voltage between and the voltage fluctuation amount signal; and a charging rate of the battery based on the open-circuit voltage value detected by the open-circuit voltage value detecting means and a charging rate estimating means for estimating the voltage change amount signal output means, and a current state signal output circuit for outputting a voltage to become the current state signal corresponding to the current value of the charging and discharging current, said current state A current adjustment resistor connected to one end of the current state signal output circuit so that a signal is input; a capacitor connected between the other end of the current adjustment resistor and the negative electrode of the battery; Serial anda discharge adjustment resistor connected in parallel with the capacitor, is characterized in that it is configured to output the voltage change amount signal from the other end of the current regulation resistor.

The invention described in claim 2 is a battery charging rate estimation device for estimating a charging rate of a battery,
A voltage fluctuation amount signal output means for outputting a voltage fluctuation amount signal corresponding to a voltage fluctuation amount with respect to an open-circuit voltage value generated by a charging / discharging current flowing through the battery at a voltage between both electrodes of the battery; and both electrodes of the battery An open-circuit voltage value detecting means for detecting the open-circuit voltage value based on the voltage between and the voltage fluctuation amount signal; and a charging rate of the battery based on the open-circuit voltage value detected by the open-circuit voltage value detecting means and a charging rate estimating means for estimating the voltage change amount signal output means, and a current state signal output circuit for outputting a voltage to become the current state signal corresponding to the current value of the charging and discharging current, said current state A signal obtained by quantizing the signal is input, and a current adjustment resistor having the current state signal input to one end thereof, a controller connected between the other end of the current adjustment resistor and the negative electrode of the battery. A computer that outputs a signal corresponding to the voltage value of the other end of the current adjustment resistor by simulating the operation of each of the sensor and the discharge adjustment resistor connected in parallel to the capacitor, and output by the computer And a digital-analog converter that outputs the voltage fluctuation amount signal based on the signal.

The invention described in claim 3 is a battery charging rate estimation device for estimating a charging rate of a battery,
A voltage fluctuation amount signal output means for outputting a voltage fluctuation amount signal corresponding to a voltage fluctuation amount with respect to an open-circuit voltage value generated by a charging / discharging current flowing through the battery at a voltage between both electrodes of the battery; and both electrodes of the battery An open-circuit voltage value detecting means for detecting the open-circuit voltage value based on the voltage between and the voltage fluctuation amount signal; and a charging rate of the battery based on the open-circuit voltage value detected by the open-circuit voltage value detecting means and a charging rate estimating means for estimating the voltage change amount signal output means, and a current state signal output circuit for outputting a voltage to become the current state signal corresponding to the current value of the charging and discharging current, said current state A signal obtained by quantizing the signal is input, and a current adjustment resistor to which the current state signal is input at one end, a capacitor connected between the other end of the current adjustment resistor and the negative electrode of the battery. A computer that simulates the operation of each of the discharge adjustment resistor connected in parallel to the capacitor and the capacitor, and calculates information corresponding to the voltage value of the other end of the current adjustment resistor as the voltage variation signal, And the open circuit voltage value detecting means receives a signal obtained by quantizing the voltage between the two electrodes of the battery, and the signal obtained by quantizing the voltage between the two electrodes of the battery and the current adjusting resistor. It has a computer which detects the open circuit voltage value based on the information according to the voltage value of the other end of the device.

According to the first to third aspects of the present invention, the voltage fluctuation amount signal output means responds to the voltage fluctuation amount with respect to the open-circuit voltage value generated by the charging / discharging current flowing in the battery at the voltage between the electrodes of the battery. Output voltage fluctuation signal. The open-circuit voltage value detecting means detects the open-circuit voltage value of the battery based on the voltage between both electrodes of the battery and the voltage fluctuation amount signal. And a charging rate estimation means estimates the charging rate of a battery based on an open circuit voltage value. As a result, the voltage between the two electrodes of the battery fluctuates to a voltage value higher than the open-circuit voltage value when the charging current flows through the battery, and becomes a voltage value lower than the open-circuit voltage value when the discharge current flows. The voltage fluctuation signal according to the voltage fluctuation amount with respect to the open-circuit voltage value generated by such charge / discharge current, when the current fluctuates and fluctuates to return to the open-circuit voltage value over time after the current stops. By providing a voltage fluctuation amount signal output means for outputting a voltage, a highly accurate open-circuit voltage value in consideration of the fluctuation is detected based on the voltage fluctuation amount signal output thereby and the voltage between both electrodes of the battery. Can do. Therefore, the estimation accuracy of the charging rate can be further improved by estimating the charging rate of the battery based on the detected open-circuit voltage value.

According to the first aspect of the present invention, the voltage fluctuation amount signal output means outputs a current state signal that outputs a voltage corresponding to the current value of the charge / discharge current flowing through the battery, and a current state Connect the current condition signal output circuit to one end so that the signal is input, the current adjustment resistor connected to one end, the capacitor connected between the other end of the current adjustment resistor and the negative electrode of the battery, and parallel to the capacitor And a voltage fluctuation amount signal is output from the other end of the current adjustment resistor. Since it did in this way, it can simplify by adjusting the resistance value of a current adjustment resistor and a discharge adjustment resistor, and the electrostatic capacitance of a capacitor according to the characteristic of the battery used as the object which presumes a charging rate. The voltage variation signal output means can be configured by the configuration. Further, since the voltage variation signal output means is constituted by an electric circuit, the voltage variation signal can be output without delay with respect to the variation of the charge / discharge current flowing through the battery.

According to the second aspect of the present invention, the voltage fluctuation amount signal output means outputs a current state signal that outputs a voltage corresponding to the current value of the charge / discharge current flowing through the battery, and the current state A signal obtained by quantizing the signal is input, and the current state signal is input to one end of the current adjustment resistor, a capacitor connected between the other end of the current adjustment resistor and the negative electrode of the battery, and a capacitor A computer that simulates the operation of each of the discharge adjustment resistors connected in parallel and outputs a signal corresponding to the voltage value at the other end of the current adjustment resistor, and a voltage fluctuation signal based on the signal output by the computer And a digital-analog converter for outputting. Thus, the operation of the current adjustment resistor, the capacitor, and the discharge adjustment resistor can be simulated relatively easily by a computer, and the voltage variation signal output means can be configured with a simple configuration. In addition, since the operations of the current adjustment resistor, the discharge adjustment resistor, and the capacitor are simulated by a computer, parameters such as the resistance value and capacitance of these electronic components can be easily adjusted.

According to the invention described in claim 3 , the voltage fluctuation amount signal output means outputs a current state signal that outputs a voltage corresponding to the current value of the charge / discharge current flowing through the battery, and a current state A signal obtained by quantizing the signal is input, and the current state signal is input to one end of the current adjustment resistor, a capacitor connected between the other end of the current adjustment resistor and the negative electrode of the battery, and a capacitor A computer for simulating the operation of each of the discharge adjustment resistors connected in parallel and calculating information corresponding to the voltage value at the other end of the current adjustment resistor as a voltage fluctuation amount signal. Then, the open circuit voltage value detecting means receives a signal obtained by quantizing the voltage between the two electrodes of the battery, and a signal obtained by quantizing the voltage between the two electrodes of the battery and the other end of the current adjusting resistor. A computer that detects an open-circuit voltage value based on information corresponding to the voltage value is included. Thus, the operation of the current adjustment resistor, the capacitor, and the discharge adjustment resistor can be simulated relatively easily by a computer, and the voltage variation signal output means can be configured with a simple configuration. In addition, since the operations of the current adjustment resistor, the discharge adjustment resistor, and the capacitor are simulated by a computer, parameters such as the resistance value and capacitance of these electronic components can be easily adjusted. The computer included in the voltage fluctuation amount signal output unit and the computer included in the open-circuit voltage value detection unit may be separate computers or a common computer.

It is a figure which shows schematic structure of the battery charging rate estimation apparatus of the 1st Embodiment of this invention. It is a figure which shows the structure of the voltage fluctuation amount signal output circuit with which the battery charge rate estimation apparatus of FIG. 1 is provided. It is a figure which shows typically an example of the relationship between the open circuit voltage value of a secondary battery, and a charging rate. 2 is a graph schematically showing an example of a charge / discharge current flowing through a secondary battery, a voltage between both electrodes of the secondary battery, and a voltage fluctuation amount signal generated in the battery charge rate estimation device of FIG. 1. It is a figure which shows schematic structure of the battery charging rate estimation apparatus of the 2nd Embodiment of this invention. It is a figure which shows schematic structure of the battery charging rate estimation apparatus of the 3rd Embodiment of this invention. It is a figure which shows typically the waveform of the voltage between the both electrodes of the secondary battery at the time of charging current energization and after energization stop.

(First embodiment)
Hereinafter, the battery charge rate estimation apparatus of the 1st Embodiment of this invention is demonstrated with reference to FIGS.

  FIG. 1 is a diagram illustrating a schematic configuration of a battery charge rate estimation apparatus according to a first embodiment of the present invention. FIG. 2 is a diagram illustrating a configuration of a voltage fluctuation amount signal output circuit provided in the battery charge rate estimation apparatus of FIG. FIG. 3 is a diagram schematically illustrating an example of the relationship between the open-circuit voltage value of the secondary battery and the charging rate.

  The battery charge rate estimation apparatus of this embodiment is installed in, for example, an electric vehicle, and estimates the charge rate of a secondary battery included in the electric vehicle. Of course, you may apply to the apparatus, system, etc. which were equipped with secondary batteries other than an electric vehicle. Alternatively, instead of the secondary battery, the present invention may be applied to an apparatus, a system, or the like provided with a primary battery. The charging rate includes the ratio of the current storage current amount to the chargeable current capacity (SOCi) and the ratio of the current storage power amount to the chargeable power capacity (SOCp). In this embodiment, the charging rate (SOC) is simply used.

  As shown in FIG. 1, the battery charge rate estimation device (indicated by reference numeral 1 in the figure) of this embodiment is connected to a secondary battery B mounted on an electric vehicle (not shown), and the charge rate of the secondary battery B Estimate the SOC.

  The secondary battery B has an electromotive force portion e that generates a voltage and an internal resistance r. The secondary battery B generates a voltage v between both electrodes (positive electrode Bp and negative electrode Bn), and this voltage v is generated by a current flowing through the voltage value ve generated by the electromotive force by the electromotive force unit e and the internal resistance r. It is determined by the voltage value vr (v = ve + vr). The open circuit voltage value OCV of the secondary battery B is a true voltage value ve generated by the electromotive force part e. The secondary battery B is connected to a load L such as a motor mounted on the electric vehicle. The voltage value generated by the electromotive force unit e varies depending on the current supplied to the secondary battery B, and returns to a true value as time elapses after the power supply is stopped. This voltage fluctuation is reproducible. When this voltage fluctuation amount is Δv, the voltage v has a relationship obtained by adding the open circuit voltage value OCV and the voltage fluctuation amount Δv (v = OCV + Δv).

  The battery charge rate estimation device 1 of the present embodiment includes a charging unit 15, a voltage fluctuation amount signal output circuit 20, an open-circuit voltage value detection circuit 27, an analog-digital converter 28, and a control unit 30. Yes.

  The charging unit 15 includes, for example, a power supply device that can output a charging current having an arbitrary current value to the secondary battery B when power is supplied from an external power source connected to the electric vehicle. The charging unit 15 has a pair of output terminals connected to the positive electrode Bp and the negative electrode Bn of the secondary battery B, respectively. The charging unit 15 is controlled by the control unit 30 to be described later, and outputs a charging current Ic having a constant current value when charging the secondary battery B.

  The voltage fluctuation amount signal output circuit 20 corresponds to voltage fluctuation amount signal output means, and a charging / discharging current flows through the secondary battery B at the voltage v between both electrodes of the secondary battery B (that is, charging current or discharging). A voltage fluctuation signal Sdv corresponding to the voltage fluctuation amount Δv with respect to the open-circuit voltage value OCV generated when the current is actually flowing and after both the charging current and the discharging current are stopped is output. As shown in FIG. 2, the voltage fluctuation signal output circuit 20 includes a current state signal output circuit 21, a current adjustment resistor 24, a capacitor 25, and a discharge adjustment resistor 26.

  The current state signal output circuit 21 includes a shunt resistor 22 connected between a terminal 20a connected to the positive electrode Bp of the secondary battery B and a terminal 20b connected to the charging unit 15 and the load L, and the shunt resistor. And an operational amplifier 23 that amplifies and outputs the voltage value at both ends of the device 22 with a predetermined amplification factor. A voltage value corresponding to the charge / discharge current flowing in the secondary battery B appears at both ends of the shunt resistor 22. Therefore, the operational amplifier 23 that amplifies the voltage value outputs a current state signal Si that is a voltage corresponding to the current value of the charge / discharge current flowing through the secondary battery B.

  In the present embodiment, as an example, the current state signal output circuit 21 has a current state of a reference potential G (reference potential G = potential of the negative electrode Bn of the secondary battery B) when no charge / discharge current flows through the secondary battery B. A signal Si is output (Si = G), a current state signal Si that is a positive voltage when a discharge current flows through the secondary battery B (Si> G), and a charging current flows through the secondary battery B It is configured to output a current state signal Si that becomes a negative voltage (Si <G). Further, in the present embodiment, the current state signal output circuit 21 is configured by combining the shunt resistor 22 and the operational amplifier 23. However, other than this, the current state signal output circuit 21 is configured by combining the current sensor and the operational amplifier. As long as the object of the invention is not violated, the circuit configuration is arbitrary as long as it outputs a current state signal Si having a voltage corresponding to the current value of the charge / discharge current flowing through the secondary battery B.

  The current adjustment resistor 24 has one end connected to the current state signal output circuit 21 and the other end connected to the terminal 20c. A current state signal Si from the current state signal output circuit 21 is input to the current adjustment resistor 24. The capacitor 25 is connected between one end of the current adjustment resistor 24 and the negative electrode Bn of the secondary battery B. The discharge adjustment resistor 26 is connected in parallel with the capacitor 25.

  By adjusting the resistance value R1 of the current adjustment resistor 24, the current value flowing from the current state signal output circuit 21 into the capacitor 25 can be adjusted. By adjusting the resistance value R2 of the discharge adjustment resistor 26, the current value flowing out of the capacitor 25 can be adjusted. Thereby, mainly by appropriately adjusting the resistance value R1 of the current adjustment resistor 24, the voltage between both terminals of the capacitor 25 is changed to the secondary battery B at the voltage v between both electrodes of the secondary battery B. The voltage fluctuation amount Δv generated when the charge / discharge current is flowing can be the same or approximate value (in practice, the voltage fluctuation amount Δv includes the voltage due to the internal resistance r of the secondary battery B). However, the voltage is removed by the control unit 30 using the internal resistance r detected separately as necessary). Further, mainly by appropriately adjusting the resistance value R2 of the discharge adjustment resistor 26, the voltage between both terminals of the capacitor 25 is charged to the secondary battery B at the voltage v between both electrodes of the secondary battery B. It can be set to a value that is the same as or close to the voltage fluctuation amount Δv that occurs after the discharge current flows and then stops. As a result, a voltage fluctuation amount signal Sdv indicating the voltage fluctuation amount Δv is output from the terminal 20c to which one end of the capacitor 25 is connected.

  The open-circuit voltage value detection circuit 27 corresponds to open-circuit voltage value detection means, and is composed of, for example, an adder circuit including an operational amplifier (not shown). The open-circuit voltage value detection circuit 27 is connected to the positive electrode Bp of the secondary battery B and the terminal 20c of the voltage fluctuation signal output circuit 20, and receives the voltage v and the voltage fluctuation signal Sdv between both electrodes of the secondary battery B. Then, the voltage fluctuation amount signal Sdv (that is, the voltage fluctuation amount Δv) is added to the voltage v, and the open voltage value signal Socv corresponding to the open voltage value OCV of the secondary battery B is output.

  The analog-digital converter 28 (hereinafter referred to as “ADC 28”) quantizes the open-circuit voltage value signal Socv output from the open-circuit voltage value detection circuit 27, and a digital value corresponding to the voltage value of the open-circuit voltage value signal Socv. A signal indicating is output. In the present embodiment, the ADC 28 is mounted as an individual electronic component. However, the ADC 28 is not limited to this, and for example, each signal using an analog-digital conversion unit built in the control unit 30 to be described later. May be quantized.

  The control unit 30 includes a microcomputer having a CPU, ROM, RAM, and the like, and controls the battery charge rate estimation apparatus 1 as a whole. The ROM stores in advance a control program for causing the CPU to function as various means such as a charging rate estimating means. The CPU functions as the various means by executing the control program.

  The control unit 30 includes an output port PO connected to the charging unit 15. The CPU of the control unit 30 controls the charging unit 15 by transmitting a control signal to the charging unit 15 through the output port PO.

  In addition, the control unit 30 includes an input port PI to which a signal from the ADC 28 is input. In the control unit 30, a signal input to the input port PI is converted into information in a format that can be recognized by the CPU and sent to the CPU. The CPU acquires the open circuit voltage value OCV of the secondary battery B based on the information.

  Further, the control unit 30 estimates the charging rate SOC of the secondary battery B based on the open circuit voltage value OCV of the secondary battery B. In the present embodiment, the end-of-charge voltage Vmax is 4.0 V and the end-of-discharge voltage Vmin is 3.0 V for the open-circuit voltage value OCV of the secondary battery B, and is opened between the end-of-charge voltage Vmax and the end-of-discharge voltage Vmin. The voltage value OCV is assumed to change linearly with respect to the charging rate SOC. That is, when the open-circuit voltage value OCV of the secondary battery B is 4.0V, the charging rate SOC is 100%, and when the open-circuit voltage value OCV is 3.5V, the charging rate SOC is 50%, and the open-circuit voltage value OCV is When it is 3.0 V, the charging rate SOC becomes 0%. Of course, this is only an example. In addition to this, for example, as shown in FIG. 3, in the case where the open-circuit voltage value OCV and the charging rate SOC of the secondary battery B do not change linearly, Charging rate relationship information such as a table relating to the relationship between the open circuit voltage value OCV and the charging rate SOC is created in advance by simulation and stored in the ROM, and the estimated open circuit voltage value OCV is applied to the charging rate relationship information. The charging rate SOC may be estimated.

  The communication port of the control unit 30 is connected to an in-vehicle network (for example, CAN (Controller Area Network)), and is connected to a display device such as a combination meter of the vehicle through the in-vehicle network. The CPU of the control unit 30 transmits the estimated charging rate SOC of the secondary battery B to the display device through the communication port and the in-vehicle network, and displays the charging rate SOC of the secondary battery B on the display device based on the signal. To do.

  Next, operation | movement of the battery charging rate estimation apparatus 1 mentioned above is demonstrated with reference to FIG.

  FIG. 4 is a graph schematically showing an example of a charge / discharge current flowing through the secondary battery, a voltage between both electrodes of the secondary battery, and a voltage fluctuation amount signal generated in the battery charge rate estimation device of FIG. is there. The values of the points intersecting the time axis (horizontal axis) in each graph shown in FIG. 4 are 0 for the charge / discharge current I, 0 for the voltage fluctuation signal Sdv, the open-circuit voltage value signal Socv, and between the electrodes of the secondary battery. The voltage v is an open circuit voltage value OCV.

  As shown in FIG. 4, depending on the state of the load L and the like, the secondary battery B has a discharge current (I> 0) or a charge current (including a regenerative current by the load L, I <0). I flows, and the voltage v between both electrodes of the secondary battery B varies according to the charge / discharge current I. This voltage v includes a variation in electromotive force caused by the charging / discharging current I flowing through the secondary battery B, that is, a voltage variation amount Δv with respect to the open circuit voltage value OCV.

  The voltage fluctuation amount signal output circuit 20 of the battery charge rate estimation device 1 has an open circuit caused by the charging / discharging current I flowing in the secondary battery B at the voltage v between both electrodes of the secondary battery B with the above-described configuration. A voltage fluctuation signal Sdv indicating a voltage fluctuation amount Δv with respect to the voltage value OCV is output. Then, the open-circuit voltage value detection circuit 27 adds the voltage fluctuation signal Sdv to the voltage v between both electrodes of the secondary battery B, that is, the open-circuit voltage value signal Socv indicating the open-circuit voltage value OCV of the secondary battery B. Is output. The open circuit voltage value signal Socv is constant in a short period in which the charge rate SOC does not change due to the charge / discharge current I. Then, control unit 30 obtains open-circuit voltage value OCV from open-circuit voltage value signal Socv, and estimates charging rate SOC of secondary battery B based on open-circuit voltage value OCV.

  As described above, according to the present embodiment, the voltage fluctuation amount signal output circuit 20 corresponds to the open-circuit voltage value OCV generated by the charging / discharging current flowing in the secondary battery B at the voltage v between both electrodes of the secondary battery B. A voltage fluctuation signal Sdv corresponding to the voltage fluctuation amount Δv is output. The open-circuit voltage value detection circuit 27 detects the open-circuit voltage value OCV of the secondary battery B based on the voltage v between both electrodes of the secondary battery B and the voltage fluctuation amount signal Sdv. Then, control unit 30 estimates charge rate SOC of secondary battery B based on open circuit voltage value OCV. As a result, the voltage v between both electrodes of the secondary battery B changes to a voltage value higher than the open circuit voltage value OCV when the charging current flows through the secondary battery B, and the discharge current flows. The voltage fluctuates to a voltage value lower than the open-circuit voltage value OCV, and after the current stops, fluctuates so as to return to the open-circuit voltage value OCV over time. By providing a voltage fluctuation amount signal output circuit 20 that outputs a voltage fluctuation amount signal Sdv corresponding to the voltage fluctuation amount Δv with respect to the voltage fluctuation amount signal Sdv outputted thereby, the voltage v between both electrodes of the secondary battery B is provided. Based on this, it is possible to detect the open-circuit voltage value OCV with high accuracy in consideration of the above-described fluctuation. Therefore, the estimation accuracy of the charging rate SOC can be further improved by estimating the charging rate SOC of the secondary battery B based on the detected open-circuit voltage value OCV.

  Further, the voltage variation signal output circuit 20 outputs a current state signal Si that outputs a voltage corresponding to the current value of the charge / discharge current flowing through the secondary battery B, and the current state signal Si is input. A current adjustment resistor 24 to which the current state signal output circuit 21 is connected at one end, a capacitor 25 connected between the other end of the current adjustment resistor 24 and the negative electrode Bn of the secondary battery B, And a discharge adjustment resistor 26 connected in parallel to the capacitor 25, and is configured to output a voltage variation signal Sdv from the other end of the current adjustment resistor 24. Since it did in this way, the secondary battery used as the object which estimates charge rate SOC from resistance value R1 of the electric current adjustment resistor 24, resistance value R2 of the discharge adjustment resistor 26, and the electrostatic capacitance C of the capacitor | condenser 25. By adjusting according to the characteristic of B, the voltage variation signal output circuit 20 can be configured with a simple configuration. Further, since the voltage variation signal output circuit 20 is configured by an electric circuit, the voltage variation signal Sdv can be output without delay with respect to the variation of the charge / discharge current flowing through the secondary battery B.

(Second Embodiment)
Hereinafter, a battery charge rate estimation apparatus according to a second embodiment of the present invention will be described with reference to FIG.

  FIG. 5 is a diagram showing a schematic configuration of a battery charge rate estimation apparatus according to the second embodiment of the present invention. In FIG. 5, the same constituent elements of the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  The battery charge rate estimation apparatus of the present embodiment includes a current adjustment resistor 24, a capacitor 25, and a discharge adjustment resistor 26 included in the voltage variation signal output circuit 20 of the battery charge rate estimation apparatus of the first embodiment described above. It is configured to simulate (simulate) with a computer and a digital-analog converter.

  The battery charge rate estimation device 2 of the present embodiment includes a charging unit 15, a current state signal output circuit 21, an open-circuit voltage value detection circuit 27, an analog-digital converter 28, and other analog-digital converters 38. , A digital-analog converter 39 and a control unit 30A.

  The other analog-to-digital converter 38 (hereinafter referred to as “ADC 38”) quantizes the current state signal Si output from the current state signal output circuit 21, and a digital value corresponding to the voltage value of the current state signal Si. A signal indicating is output. In the present embodiment, the ADC 38 is mounted as an individual electronic component. However, the ADC 38 is not limited to this. For example, each signal using an analog-digital conversion unit built in the control unit 30A described later is used. May be quantized.

  The digital-analog converter 39 (hereinafter referred to as “DAC39”) receives a signal indicating a voltage fluctuation amount signal Sdv indicating a voltage fluctuation amount Δv of the secondary battery B output from the control unit 30A described later as a digital value. Based on this signal, the voltage fluctuation amount signal Sdv, which is an analog signal, is output. The voltage variation signal Sdv output from the DAC 39 is input to the open circuit voltage value detection circuit 27. In this embodiment, the DAC 39 is mounted as an individual electronic component. However, the DAC 39 is not limited to this. For example, the DAC 39 is a digital signal using a digital-analog conversion unit built in the control unit 30A described later. May be converted into an analog signal.

  Similar to the control unit 30 of the first embodiment described above, the control unit 30A is configured by a microcomputer incorporating a CPU, a ROM, a RAM, and the like, and controls the entire battery charge rate estimation apparatus 2. The ROM stores in advance a control program for causing the CPU to function as a part of the voltage fluctuation amount signal output means and various means such as the charging rate estimation means. The CPU functions as the various means by executing the control program.

  The control unit 30A includes an output port PO connected to the charging unit 15. The CPU of the control unit 30A controls the charging unit 15 by transmitting a control signal to the charging unit 15 through the output port PO.

  In addition, the control unit 30A includes an input port PI to which a signal from the ADC 28 is input. In the control unit 30A, a signal input to the input port PI is converted into information in a format that can be recognized by the CPU and sent to the CPU. The CPU acquires the open circuit voltage value OCV of the secondary battery B based on the information.

  Further, the control unit 30A estimates the charging rate SOC of the secondary battery B based on the open circuit voltage value OCV of the secondary battery B. In the present embodiment, the end-of-charge voltage Vmax is 4.0 V and the end-of-discharge voltage Vmin is 3.0 V for the open-circuit voltage value OCV of the secondary battery B, and is opened between the end-of-charge voltage Vmax and the end-of-discharge voltage Vmin. The voltage value OCV is assumed to change linearly with respect to the charging rate SOC. That is, when the open-circuit voltage value OCV of the secondary battery B is 4.0V, the charging rate SOC is 100%, and when the open-circuit voltage value OCV is 3.5V, the charging rate SOC is 50%, and the open-circuit voltage value OCV is When it is 3.0 V, the charging rate SOC becomes 0%. Of course, this is only an example. In addition to this, for example, as shown in FIG. 3, in the case where the open-circuit voltage value OCV and the charging rate SOC of the secondary battery B do not change linearly, Charging rate relationship information such as a table relating to the relationship between the open circuit voltage value OCV and the charging rate SOC is created in advance by simulation and stored in the ROM, and the estimated open circuit voltage value OCV is applied to the charging rate relationship information. The charging rate SOC may be estimated.

  Further, the control unit 30A includes another input port PI2 to which a signal from the ADC 38 is input. In the control unit 30A, a signal input to the other input port PI2 is converted into information in a format that can be recognized by the CPU and sent to the CPU. The CPU acquires the current state signal Si based on the information.

  Further, the control unit 30A acquires the voltage fluctuation amount signal Sdv based on the current state signal Si. Specifically, the operations of the current adjustment resistor 24, the capacitor 25, and the discharge adjustment resistor 26 included in the voltage variation signal output circuit 20 of the first embodiment described above are simulated. That is, the control unit 30A includes a current adjustment resistor 24 to which the current state signal Si is input at one end, a capacitor 25 connected between the other end of the current adjustment resistor 24 and the negative electrode Bn of the battery B, and a capacitor 25 The information corresponding to the voltage value of the other end of the current adjustment resistor 24 is calculated as the voltage variation signal Sdv by simulating the operation of the discharge adjustment resistor 26 connected in parallel with each other. The control unit 30A includes another output port PO2 connected to the DAC 39, and the CPU of the control unit 30A transmits a signal indicating the voltage variation signal Sdv as a digital value to the DAC 39 through the other output port PO2. To do.

  The communication port of the control unit 30A is connected to an in-vehicle network (for example, CAN (Controller Area Network)), and is connected to a display device such as a combination meter of the vehicle through the in-vehicle network. The CPU of the control unit 30A transmits the estimated charging rate SOC of the secondary battery B to the display device through the communication port and the in-vehicle network, and displays the charging rate SOC of the secondary battery B on the display device based on the signal. To do.

  Next, the operation of the above-described battery charging rate estimation device 2 will be described.

  The current state signal output circuit 21 of the battery charge rate estimation device 2 has the above-described configuration, and the charge / discharge current I flows through the secondary battery B at the voltage v between both electrodes of the secondary battery B. A current state signal Si having a voltage corresponding to the current value of the current I is output. The control unit 30A receives the current state signal Si through the ADC 38, and based on the current state signal Si, determines the voltage fluctuation amount Δv with respect to the open-circuit voltage value OCV generated by the charge / discharge current I flowing through the secondary battery B. A voltage fluctuation amount signal Sdv shown is calculated and output through the DAC 39. Then, the open-circuit voltage value detection circuit 27 adds the voltage fluctuation signal Sdv to the voltage v between both electrodes of the secondary battery B, that is, the open-circuit voltage value signal Socv indicating the open-circuit voltage value OCV of the secondary battery B. Is output. The open circuit voltage value signal Socv is constant in a short period in which the charge rate SOC does not change due to the charge / discharge current I. Then, control unit 30A acquires open-circuit voltage value OCV from open-circuit voltage value signal Socv, and estimates charging rate SOC of secondary battery B based on open-circuit voltage value OCV. In the present embodiment, the current state signal output circuit 21, the control unit 30A, and the DAC 39 constitute a voltage fluctuation amount signal output unit, and the control unit 30A constitutes a charging rate estimation unit.

  As described above, according to the present embodiment, the current state signal output circuit 21, the control unit 30A, and the DAC 39 are generated by the charging / discharging current flowing through the secondary battery B at the voltage v between both electrodes of the secondary battery B. A voltage fluctuation signal Sdv corresponding to the voltage fluctuation amount Δv with respect to the open circuit voltage value OCV is output. The open-circuit voltage value detection circuit 27 detects the open-circuit voltage value OCV of the secondary battery B based on the voltage v between both electrodes of the secondary battery B and the voltage fluctuation amount signal Sdv. Then, control unit 30A estimates charge rate SOC of secondary battery B based on open circuit voltage value OCV. As a result, the voltage v between both electrodes of the secondary battery B changes to a voltage value higher than the open circuit voltage value OCV when the charging current flows through the secondary battery B, and the discharge current flows. The voltage fluctuates to a voltage value lower than the open-circuit voltage value OCV, and after the current stops, fluctuates so as to return to the open-circuit voltage value OCV over time. The voltage fluctuation amount signal Sdv corresponding to the voltage fluctuation amount Δv is output by the current state signal output circuit 21, the control unit 30A and the DAC 39, so that the output voltage fluctuation amount signal Sdv and between both electrodes of the secondary battery B are output. On the basis of the voltage v, the open circuit voltage value OCV can be detected with high accuracy in consideration of the above fluctuation. Therefore, the estimation accuracy of the charging rate SOC can be further improved by estimating the charging rate SOC of the secondary battery B based on the detected open-circuit voltage value OCV.

  Further, as a voltage fluctuation amount signal output means, a current state signal output circuit 21 that outputs a current state signal Si that has a voltage corresponding to the current value of the charge / discharge current I that flows through the secondary battery B, and the current state signal Si is quantized. And the current state signal Si is input to one end, a capacitor connected between the other end of the current adjustment resistor and the negative electrode of the battery, and the capacitor in parallel A control unit 30A for simulating the operation of each connected discharge adjustment resistor and outputting a signal corresponding to the voltage value at the other end of the current adjustment resistor, and a voltage fluctuation based on the signal output by the control unit 30A And a DAC 39 for outputting a quantity signal Sdv. Since it did in this way, the resistance value of a current adjustment resistor and a discharge adjustment resistor, and the electrostatic capacitance (namely, parameter) of a capacitor should be adjusted according to the characteristic of the battery for which a charge rate is estimated. Thus, the voltage variation signal Sdv can be acquired with a simple configuration, and the operations of the current adjustment resistor, the discharge adjustment resistor and the capacitor are simulated by the control unit 30A which is a computer. Can be easily adjusted.

  In the above-described embodiment, the control unit 30A that controls the entire battery charging rate estimation apparatus 2 is configured to simulate the operations of the current adjustment resistor 24, the capacitor 25, and the discharge adjustment resistor 26. However, a computer that simulates these electronic components may be provided separately from the control unit 30A.

(Third embodiment)
Hereinafter, the battery charge rate estimation apparatus of the 3rd Embodiment of this invention is demonstrated with reference to FIG.

  FIG. 6 is a diagram showing a schematic configuration of a battery charge rate estimation apparatus according to the third embodiment of the present invention. In FIG. 6, the same constituent elements of the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

  The battery charge rate estimation apparatus of the present embodiment includes a current adjustment resistor 24, a capacitor 25, a discharge adjustment resistor 26, and a voltage fluctuation amount signal output circuit 20 of the battery charge rate estimation apparatus of the first embodiment described above, and The open circuit voltage detection circuit 27 is configured to be simulated (simulated) by a computer.

  The battery charging rate estimation device 3 of the present embodiment includes a charging unit 15, a current state signal output circuit 21, a first analog-digital converter 41, a second analog-digital converter 42, a control unit 30B, It has.

  The first analog-digital converter 41 (hereinafter referred to as “ADC41”) quantizes the voltage v between both electrodes of the secondary battery B, and outputs a signal indicating a digital value corresponding to the voltage value of the voltage v. To do.

  The second analog-digital converter 42 (hereinafter referred to as “ADC 42”) quantizes the current state signal Si output from the current state signal output circuit 21, and a digital value corresponding to the voltage value of the current state signal Si. A signal indicating is output. In the present embodiment, the ADC 41 and the ADC 42 are mounted as individual electronic components. However, the present invention is not limited to this. For example, an analog-digital conversion unit built in the control unit 30B described later is used. Each signal may be quantized.

  Similar to the control unit 30 of the first embodiment described above, the control unit 30B is configured by a microcomputer having a built-in CPU, ROM, RAM, and the like, and controls the entire battery charge rate estimation apparatus 3. The ROM stores in advance a control program for causing the CPU to function as various means such as a part of voltage fluctuation amount signal output means, an open-circuit voltage value detection means, and a charge rate estimation means. The CPU functions as the various means by executing the control program.

  The control unit 30 </ b> B includes an output port PO connected to the charging unit 15. The CPU of the control unit 30B controls the charging unit 15 by transmitting a control signal to the charging unit 15 through the output port PO.

  Further, the control unit 30B includes a first input port PI1 into which a signal from the ADC 41 is input. In the control unit 30B, the signal input to the first input port PI1 is converted into information in a format that can be recognized by the CPU and sent to the CPU. The CPU acquires the voltage v between both electrodes of the secondary battery B based on the information.

  In addition, the control unit 30B includes a second input port PI2 to which a signal from the ADC 42 is input. In the control unit 30B, the signal input to the second input port PI2 is converted into information in a format that can be recognized by the CPU and sent to the CPU. The CPU acquires the current state signal Si based on the information.

  In addition, the control unit 30B acquires the voltage fluctuation amount signal Sdv based on the current state signal Si. Specifically, the operations of the current adjustment resistor 24, the capacitor 25, and the discharge adjustment resistor 26 included in the voltage variation signal output circuit 20 of the first embodiment described above are simulated. That is, the control unit 30B includes a current adjustment resistor 24 to which the current state signal Si is input at one end, a capacitor 25 connected between the other end of the current adjustment resistor 24 and the negative electrode Bn of the battery B, and a capacitor 25 The information corresponding to the voltage value of the other end of the current adjustment resistor 24 is calculated as the voltage variation signal Sdv by simulating the operation of the discharge adjustment resistor 26 connected in parallel with each other. That is, if the process for calculating the voltage fluctuation amount signal Sdv is performed in one logical processing block, and the calculated voltage fluctuation amount signal Sdv is used in another logical processing block, this processing block It can be considered that the voltage variation signal Sdv is output to the block.

  Further, the control unit 30B detects the open circuit voltage value OCV of the secondary battery B based on the voltage v between both electrodes of the secondary battery B acquired from the signals input to the ADC 41 and the ADC 42 and the voltage variation signal Sdv. To do. Specifically, the control unit 30B adds the voltage fluctuation amount signal Sdv (that is, the voltage fluctuation amount Δv) to the voltage v between both electrodes of the secondary battery B to obtain the open-circuit voltage value OCV of the secondary battery B. calculate.

  Further, the control unit 30B estimates the charging rate SOC of the secondary battery B based on the calculated open-circuit voltage value OCV of the secondary battery B. In the present embodiment, the end-of-charge voltage Vmax is 4.0 V and the end-of-discharge voltage Vmin is 3.0 V for the open-circuit voltage value OCV of the secondary battery B, and is opened between the end-of-charge voltage Vmax and the end-of-discharge voltage Vmin. The voltage value OCV is assumed to change linearly with respect to the charging rate SOC. That is, when the open-circuit voltage value OCV of the secondary battery B is 4.0V, the charging rate SOC is 100%, and when the open-circuit voltage value OCV is 3.5V, the charging rate SOC is 50%, and the open-circuit voltage value OCV is When it is 3.0 V, the charging rate SOC becomes 0%. Of course, this is only an example. In addition to this, for example, as shown in FIG. 3, in the case where the open-circuit voltage value OCV and the charging rate SOC of the secondary battery B do not change linearly, Charging rate relationship information such as a table relating to the relationship between the open circuit voltage value OCV and the charging rate SOC is created in advance by simulation and stored in the ROM, and the estimated open circuit voltage value OCV is applied to the charging rate relationship information. The charging rate SOC may be estimated.

  Further, the communication port of the control unit 30B is connected to an in-vehicle network (for example, CAN (Controller Area Network)), and is connected to a display device such as a combination meter of the vehicle through the in-vehicle network. The CPU of the control unit 30B transmits the estimated charging rate SOC of the secondary battery B to the display device through the communication port and the in-vehicle network, and displays the charging rate SOC of the secondary battery B on the display device based on the signal. To do.

  Next, operation | movement of the battery charging rate estimation apparatus 3 mentioned above is demonstrated.

  The current state signal output circuit 21 of the battery charging rate estimation device 3 has the above-described configuration, and the charging / discharging current I flows through the secondary battery B at the voltage v between both electrodes of the secondary battery B. A current state signal Si having a voltage corresponding to the current value of the current I is output. The control unit 30B receives a current state signal Si through the ADC 42, and based on the current state signal Si, calculates a voltage fluctuation amount Δv with respect to the open-circuit voltage value OCV generated by the charge / discharge current I flowing through the secondary battery B. A voltage fluctuation amount signal Sdv shown is calculated. In addition, the voltage v between both electrodes of the secondary battery B is input to the control unit 30B through the ADC 41. Then, the control unit 30B calculates the open-circuit voltage value OCV of the secondary battery B based on the voltage v between both electrodes of the secondary battery B and the voltage variation signal Sdv, and the secondary battery based on the open-circuit voltage value OCV. B charge rate SOC is estimated. In the present embodiment, the current state signal output circuit 21 and the control unit 30B constitute a voltage fluctuation amount signal output unit, and the control unit 30B constitutes an open-circuit voltage value detection unit and a charging rate estimation unit.

  As described above, according to the present embodiment, the current state signal output circuit 21 and the control unit 30B have the open voltage generated by the charging / discharging current flowing in the secondary battery B at the voltage v between both electrodes of the secondary battery B. A voltage fluctuation signal Sdv corresponding to the voltage fluctuation amount Δv with respect to the value OCV is calculated. The control unit 30B detects the open circuit voltage value OCV of the secondary battery B based on the voltage v between both electrodes of the secondary battery B and the voltage variation signal Sdv. Then, control unit 30B estimates the charging rate SOC of secondary battery B based on open circuit voltage value OCV. As a result, the voltage v between both electrodes of the secondary battery B changes to a voltage value higher than the open circuit voltage value OCV when the charging current flows through the secondary battery B, and the discharge current flows. The voltage fluctuates to a voltage value lower than the open-circuit voltage value OCV, and after the current stops, fluctuates so as to return to the open-circuit voltage value OCV over time. By calculating the voltage fluctuation amount signal Sdv according to the voltage fluctuation amount Δv with respect to the voltage fluctuation amount signal Sdv and the voltage v between both electrodes of the secondary battery B, the above fluctuation is considered. The open-circuit voltage value OCV with high accuracy can be detected. Therefore, the estimation accuracy of the charging rate SOC can be further improved by estimating the charging rate SOC of the secondary battery B based on the detected open-circuit voltage value OCV.

  Further, as a voltage fluctuation amount signal output means, a current state signal output circuit 21 that outputs a current state signal Si that has a voltage corresponding to the current value of the charge / discharge current I that flows through the secondary battery B, and the current state signal Si is quantized. A current adjusting resistor to which the current state signal Si is input at one end, a capacitor connected between the other end of the current adjusting resistor and the negative electrode of the battery, and a capacitor in parallel A control unit 30B that simulates the operation of each of the connected discharge adjustment resistors and calculates information corresponding to the voltage value at the other end of the current adjustment resistor as the voltage variation signal Sdv. Then, as an open-circuit voltage value detection means, a signal obtained by quantizing the voltage v between both electrodes of the secondary battery B is input, and a signal and current obtained by quantizing the voltage v between both electrodes of the secondary battery B are input. The control unit 30B detects the open circuit voltage value OCV based on the voltage variation signal Sdv, which is information corresponding to the voltage value at the other end of the adjustment resistor. Since it did in this way, the resistance value of a current adjustment resistor and a discharge adjustment resistor, and the electrostatic capacitance (namely, parameter) of a capacitor should be adjusted according to the characteristic of the battery for which a charge rate is estimated. Thus, the voltage variation signal Sdv can be acquired with a simple configuration, and the operation of the current adjustment resistor, the discharge adjustment resistor, and the capacitor is simulated by the control unit 30B. It can be adjusted easily.

  As mentioned above, although this invention was mentioned and mentioned with preferable embodiment, the battery charging rate estimation apparatus of this invention is not limited to the structure of these embodiment.

  For example, in the first embodiment described above, the configuration includes the voltage fluctuation amount signal output circuit 20 and the open-circuit voltage value detection circuit 27 that are configured by electronic components. However, the present invention is not limited to this. Absent. In addition to such a configuration, for example, a current measurement unit that measures a current value flowing through the secondary battery B, a voltage measurement unit that measures a voltage value between both electrodes of the secondary battery B, and a measurement by these measurement units It is good also as a structure provided with the control part into which the measured electric current value and voltage value are input via an analog-digital converter. In this configuration, the control unit stores in advance open-circuit voltage value relationship information such as a table and a calculation formula regarding the relationship between the input current value and the voltage fluctuation amount Δv with respect to the open-circuit voltage value OCV of the secondary battery B. . Then, the control unit applies the input current value to the open-circuit voltage value relation information to obtain the open-circuit voltage value OCV, and estimates the charge rate SOC based on the open-circuit voltage value OCV as in the above embodiment.

  In addition, embodiment mentioned above only showed the typical form of this invention, and this invention is not limited to embodiment. That is, those skilled in the art can implement various modifications in accordance with conventionally known knowledge without departing from the scope of the present invention. Of course, such modifications are included in the scope of the present invention as long as the configuration of the battery charge rate estimating apparatus of the present invention is provided.

(First embodiment)
DESCRIPTION OF SYMBOLS 1 Battery charge rate estimation apparatus 20 Voltage fluctuation amount signal output circuit (Voltage fluctuation amount signal output means)
DESCRIPTION OF SYMBOLS 21 Current state signal output circuit 24 Current adjustment resistor 25 Capacitor 26 Discharge adjustment resistor 27 Open-circuit voltage value detection circuit (open-circuit voltage value detection means)
28 Analog-Digital Converter 30 Control Unit (Charging Rate Estimator)
B Secondary battery (battery)
Bp Positive electrode of secondary battery Bn Negative electrode of secondary battery (second embodiment)
2 Battery charge rate estimation device 21 Current state signal output circuit (voltage fluctuation amount signal output means)
27 Open-circuit voltage value detection circuit (open-circuit voltage value detection means)
28 Analog-to-digital converter 30A Control unit (computer, voltage fluctuation signal output means, charging rate estimation means)
38 Analog-to-digital converter 39 Digital-to-analog converter (voltage fluctuation amount signal output means)
(Third embodiment)
3 Battery charge rate estimation device 21 Current state signal output circuit (voltage fluctuation amount signal output means)
30B control unit (computer, voltage fluctuation signal output means, open-circuit voltage value detection means, charge rate estimation means)
41 1st analog-digital converter 42 2nd analog-digital converter

Claims (3)

A battery charging rate estimation device for estimating a charging rate of a battery,
A voltage fluctuation amount signal output means for outputting a voltage fluctuation amount signal corresponding to a voltage fluctuation amount with respect to an open-circuit voltage value generated by a charge / discharge current flowing through the battery at a voltage between both electrodes of the battery;
An open-circuit voltage value detecting means for detecting the open-circuit voltage value based on the voltage between both electrodes of the battery and the voltage fluctuation amount signal;
Charging rate estimating means for estimating the charging rate of the battery based on the open voltage value detected by the open voltage value detecting means ,
The voltage fluctuation amount signal output means,
A current state signal output circuit that outputs a current state signal having a voltage corresponding to the current value of the charge / discharge current;
A current regulating resistor connected to one end of the current state signal output circuit so that the current state signal is input;
A capacitor connected between the other end of the current regulating resistor and the negative electrode of the battery;
A discharge regulating resistor connected in parallel to the capacitor,
The battery charge rate estimation device is configured to output the voltage variation signal from the other end of the current adjustment resistor . A battery charging rate estimation device for estimating a charging rate of a battery,
A voltage fluctuation amount signal output means for outputting a voltage fluctuation amount signal corresponding to a voltage fluctuation amount with respect to an open-circuit voltage value generated by a charge / discharge current flowing through the battery at a voltage between both electrodes of the battery;
An open-circuit voltage value detecting means for detecting the open-circuit voltage value based on the voltage between both electrodes of the battery and the voltage fluctuation amount signal;
Charging rate estimating means for estimating the charging rate of the battery based on the open voltage value detected by the open voltage value detecting means ,
The voltage fluctuation amount signal output means,
A current state signal output circuit that outputs a current state signal having a voltage corresponding to the current value of the charge / discharge current;
A signal obtained by quantizing the current state signal is input and the current state signal is input to one end of the current adjustment resistor, and is connected between the other end of the current adjustment resistor and the negative electrode of the battery. A computer that simulates the operation of each of the capacitor and the discharge adjustment resistor connected in parallel to the capacitor and outputs a signal corresponding to the voltage value of the other end of the current adjustment resistor;
A battery charge rate estimation apparatus comprising: a digital-analog converter that outputs the voltage fluctuation amount signal based on the signal output by the computer . A battery charging rate estimation device for estimating a charging rate of a battery,
A voltage fluctuation amount signal output means for outputting a voltage fluctuation amount signal corresponding to a voltage fluctuation amount with respect to an open-circuit voltage value generated by a charge / discharge current flowing through the battery at a voltage between both electrodes of the battery;
An open-circuit voltage value detecting means for detecting the open-circuit voltage value based on the voltage between both electrodes of the battery and the voltage fluctuation amount signal;
Charging rate estimating means for estimating the charging rate of the battery based on the open voltage value detected by the open voltage value detecting means ,
The voltage fluctuation amount signal output means,
A current state signal output circuit that outputs a current state signal having a voltage corresponding to the current value of the charge / discharge current;
A signal obtained by quantizing the current state signal is input and the current state signal is input to one end of the current adjustment resistor, and is connected between the other end of the current adjustment resistor and the negative electrode of the battery. A computer that simulates each operation of a capacitor and a discharge adjustment resistor connected in parallel to the capacitor, and calculates information corresponding to the voltage value of the other end of the current adjustment resistor as the voltage variation signal; Have
The open-circuit voltage value detecting means receives a signal obtained by quantizing the voltage between both electrodes of the battery, and a signal obtained by quantizing the voltage between both electrodes of the battery and the other end of the current adjusting resistor. A battery charge rate estimation device , comprising: a computer that detects the open-circuit voltage value based on information corresponding to the voltage value of the battery.

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