JP2013072838A - Battery tester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery tester capable of appropriately determining a state of a battery even for a battery for ISS vehicles.SOLUTION: A battery tester 1: stores a plurality of determination maps which define relations among OCV, CCA and a state of a battery, include a good area and a charging-required area adjacent to each other through a charging-required threshold as the state of the battery, and are different in at least charging-required thresholds in correspondence to types of batteries; calculates the CCA of a battery 10 from the OCV and voltages across resistances R1 and R2, measured in a voltage measurement circuit 3, and electric currents passing through resistances R1 and R2, measured in current measurement circuits 41 and 42; switches the determination maps according to information for specifying the type of the battery 10 inputted from an input operation part 6; and applies the measured OCV and the calculated CCA to the switched determination maps to estimate the state of the battery 10.

Description

  The present invention relates to a battery tester, and more particularly, to a battery tester that estimates a battery state using a determination map.

  Batteries are used in equipment such as UPS, emergency lights, emergency broadcasting equipment, telephone exchanges, communication equipment base stations, etc. that are supposed to be backed up in an emergency, automobiles, and electric vehicles. These devices cannot function due to deterioration or discharge of the battery. In order to avoid this, there is an apparatus for confirming whether the performance of the battery is degraded. As such a device, for example, a battery monitoring device having no battery discharging function and a battery tester having a battery discharging function are known.

  The battery tester discharges the battery in pulses and displays the internal resistance and conductivity (reciprocal of the internal resistance) obtained from the voltage and current at that time, or displays the value converted into cold cranking amperage (CCA). . The battery tester can also detect the state of charge (SOC) of the battery, and estimates and displays it from the battery voltage in a state where no current is flowing or in a state where only current is flowing. .

  The health level (SOH) and capacity of a deteriorated battery can be obtained by measuring parameters of the equivalent circuit by curve fitting to frequency dispersion data of complex impedance. However, since the applied waveform is a sine wave, the device High cost and uncommon.

  A general battery tester is based on a constant resistance discharge (see, for example, Patent Document 1), which is roughly divided to discharge a battery for about 5 seconds with a large current of 100 A and 1 ms to 10 ms at 1 A to 100 A. There is something to discharge. The former simulates the current at the time of engine start and is valid as a test method for the engine start battery. Since the latter has a sufficiently short single pulse time width, it is common to discharge a plurality of times, and a plurality of obtained data are used for accuracy improvement processing such as averaging processing. The latter is generally small and has become popular in recent years.

  In such a battery tester, a voltage of about 12.6 V has been generally adopted as an open circuit voltage (OCV) of a charge required determination threshold value for determining whether or not the battery needs to be charged.

Japanese Patent No. 4414757 (FIG. 2)

  However, since batteries for idle stop start (ISS) vehicles and charge control vehicles including regenerative charging, which have become widespread in recent years, are used in a state where the SOC is low, it is usually used as the OCV of the required charging threshold value. When the same 12.6V as that for automobiles is used, the determination of charging required frequently occurs.

  An object of the present invention is to provide a battery tester capable of appropriately determining the state even with a battery for an ISS vehicle or a charge control vehicle.

  In order to solve the above-mentioned problems, the present invention provides an energization circuit having a constant resistance and connected in parallel to a battery, a voltage for measuring an open circuit voltage (OCV) of the battery and a voltage across the constant resistance of the energization circuit. Measuring means, current measuring means for measuring the current flowing through the energization circuit, input means for inputting information for specifying the type of the battery, storage means for storing a judgment map, and storage means Control means for estimating the state of the battery using a stored determination map, wherein the storage means includes an OCV or state of charge (SOC) of the battery, a cold cranking ampere (CCA) of the battery, or a health degree. (SOH) or internal resistance (Ir) is a map that defines the relationship between the battery state and adjacent to the battery state via a charge threshold A plurality of determination maps having different charge threshold values corresponding to the type of battery, and the control means is measured by the voltage measurement means. While calculating the value of CCA or SOH or Ir of the battery from the OCV of the battery and the voltage across the constant resistance, and the value of the current flowing through the energization circuit measured by the current measuring means, and if necessary The SOC value of the battery is calculated from the OCV of the battery measured by the voltage measuring unit, and the determination map is switched according to information for specifying the type of the battery input by the input unit, The measured OCV or the calculated SOC and the calculated CCA or SOH or Ir value in the switched determination map Estimating the state of the battery by fitting, characterized in that.

  In the present invention, the information for specifying the type of battery may include at least one of a battery type, a battery type, and a vehicle type in which the battery is mounted. At this time, at least one of an idle stop start (ISS) vehicle battery and a charge control vehicle battery is included in the battery type, and at least one of the ISS vehicle and the charge control vehicle is included in the vehicle type in which the battery is mounted. Is preferred. Moreover, you may make it further provide the display means which displays the screen for making an operator select the information for specifying the kind of battery with an input means. Furthermore, an acquisition unit for acquiring information for specifying the battery type from the outside is provided, and the control unit switches the determination map according to the information for specifying the type of battery acquired by the acquisition unit, and The battery state may be estimated by applying the measured OCV or the calculated SOC and the calculated CCA, SOH, or Ir value to the switched determination map.

  In the present invention, the control means is configured to determine the ohmic resistance value of the battery from the voltage across the battery OCV and the constant resistance measured by the voltage measurement means, and the value of the current flowing through the energization circuit measured by the current measurement means. And the battery's OCV measured by the voltage measuring means, the calculated ohmic resistance value, and the charge transfer resistance value to calculate the CCA, SOH, or Ir value of the battery, and if necessary The SOC value of the battery may be calculated from the OCV of the battery measured by the voltage measuring means. At this time, the plurality of determination maps stored in the storage means are maps that define the relationship between the OCV, the CCA, and the state of the battery, and the control means uses the measured OCV and the calculated ohmic resistance value. Then, the CCA value is calculated from the charge transfer resistance value, and the battery state is estimated by applying the measured OCV and the calculated CCA value to the switched determination map, or stored in the storage means. The plurality of determination maps are maps that define the relationship between the SOC, SOH or Ir, and the battery state, and the storage means includes a first relationship map that defines the relationship between the battery OCV and the SOC, and A second relationship map that defines the relationship between the charge transfer resistance of the battery and SOH or Ir is further stored, and the control means stores the measured OCV in the first relationship map. To calculate the SOC value of the battery, apply the calculated charge transfer resistance value to the second relationship map to calculate the SOH or Ir value of the battery, and calculate the SOC and SOH calculated in the switched determination map Alternatively, the state of the battery may be estimated by applying the value of Ir.

  Furthermore, in the present invention, a second display unit that displays the estimation result of the battery state by the control unit may be further provided. At this time, the second display means displays an LED for indicating that the battery is in a good state, an LED for indicating that the battery is in a required charging state, and that the battery is in a required replacement state. You may have LED for displaying.

  According to the present invention, the control means switches between a plurality of determination maps having different charge thresholds corresponding to the battery type according to the information for specifying the battery type input by the input means. (By selecting a determination map corresponding to the type of battery) and estimating the state of the battery, it is possible to obtain an effect that the state can be properly determined even with a battery for an ISS vehicle or a charge control vehicle. it can.

It is a top view of the battery tester of embodiment which can apply this invention. It is a block circuit diagram of the battery tester of the embodiment. It is a flowchart of the battery state estimation routine which CPU of the microprocessor of the battery tester of the embodiment executes. It is explanatory drawing which shows the application waveform of the electric current which supplies with electricity to a battery. It is a Nyquist plot of the frequency which controls a switch to an ON state. It is explanatory drawing which shows the error of internal resistance resulting from the error of a frequency. FIG. 3 is an explanatory diagram of a determination map for a normal automobile battery that represents a relationship among an open circuit voltage (OCV), a cold cranking amperage (CCA), and a battery state, which is stored in the ROM of the microprocessor of the battery tester of the embodiment. is there. Judgment of battery for ISS vehicle and charge control vehicle representing relationship between open circuit voltage (OCV), cold cranking ampere (CCA), and battery state stored in ROM of microprocessor of battery tester of embodiment It is explanatory drawing of a map. It is explanatory drawing of the relationship map showing the relationship between the open circuit voltage of a battery and a charge state stored in ROM of the microprocessor of the battery tester of embodiment. It is explanatory drawing of the relationship map showing the relationship between the internal resistance of a battery and the health degree stored in ROM of the microprocessor of the battery tester of embodiment.

  Hereinafter, an embodiment in which the present invention is applied to a battery tester capable of estimating the states of a plurality of types of batteries for automobiles with reference to the drawings will be described. In this example, in order to simplify the description, a battery tester capable of estimating the states of a normal vehicle battery, an idle stop start (ISS) vehicle and a charge control vehicle battery will be exemplified.

<Appearance configuration>
As shown in FIG. 1, the battery tester 1 of the present embodiment includes a rectangular tester main body and two clips for connecting to a positive and negative external terminal of a battery that is derived from the tester main body and is a test (inspection) target. And have.

  On the front side of the tester body, in order from the top, there is a mini printer 8 that prints the state estimation result of the test target battery (see also reference numeral 10 in FIG. 2) by the battery tester 1 and has three LEDs to indicate the state of the test target battery. A display unit 12 for displaying, a liquid crystal display (LCD) 7, an input operation unit 6 for selecting information for specifying the type of battery to be tested from a screen having five push keys and displayed on the LCD 7. It is installed. A USB terminal 11 is arranged on the side surface (right side in FIG. 1) of the corresponding tester body from the lower part of the mini printer 8 to the display unit 12.

  The mini printer 8 incorporates a replaceable hoop-like printing paper, and has a function of discharging the printed paper portion to the outside (the front side in FIG. 1). The printing paper is built in the mini printer 8 through an opening / closing lid. The mini printer 8 also has a jagged cutter for cutting out the edge of the discharged printed paper portion.

  The display unit 12 has a green LED for displaying that the test target battery is in a good state, a yellow LED for displaying that the test target battery is in a required charge state, and the test target battery is in a replacement required state. It has a red LED to indicate this. These LEDs have a resistor and a switch element such as a transistor, and are lit by electric power supplied from an operating unit (a part of the display unit 12) arranged inside the tester body.

  The LCD 7 displays a screen for allowing an operator (user) to select information for specifying the type of the battery to be tested in accordance with an instruction from the microprocessor (see reference numeral 2 in FIG. 2).

  The input operation unit 6 has an upper scroll key (△), a lower scroll key (▽), a menu key, and a return key arranged in an annular shape around a circular enter key. It has a shape. The enter key is pressed when the operator determines a selection item on the screen displayed on the LCD 7, the up / down scroll key is pressed when the selection item on the screen displayed on the LCD 7 is scrolled up / down, and the menu key is displayed on the LCD 7. Is pressed when the menu screen is displayed, and the return key is pressed when returning to the previous screen of the screen displayed on the LCD 7.

  The USB terminal 11 is used for connection with a USB memory or a USB cable. From a personal computer (PC) connected via the USB memory or the USB cable (from the outside), instead of input by the input operation unit 6 ( Alternatively, it is used to acquire information for specifying the type of the test target battery (with input from the input operation unit 6).

<Internal configuration>
As shown in FIG. 2, the battery tester 1 is connected to a positive external terminal and a negative external terminal of a test target battery (hereinafter simply referred to as a battery) 10 for an automobile via positive and negative clips. FIG. 2 shows a state in which the battery tester 1 is connected to positive and negative external terminals of the battery 10 via positive and negative clips by an operator (user).

  In order to prevent erroneous connection when the positive and negative clip is connected to the positive external terminal and the negative external terminal, the color of the cover covering the clip is different. In this example, a red cover is used for the clip for connecting to the positive external terminal of the battery 10, and a black cover is used for the clip for connecting to the negative external terminal. In this example, a temperature sensor such as the thermistor TH is fixed to the positive clip connected to the positive external terminal.

  The positive and negative clip includes a first energization circuit in which a first switch SW1 and a first resistor R1 are connected in series, and a second switch SW2 and a second resistor R2 in series. Each of the two energization circuits is connected in parallel. The first switch SW1 and the second switch SW2 can be configured by switching elements such as FETs, for example.

  A voltage measuring circuit 3 that measures an open circuit voltage value (OCV) of the battery 10 is connected to the positive and negative clips. The voltage measurement circuit 3 further includes a voltage value (V1) across the first resistor R1 when the first switch SW1 is closed (when turned on) and a value when the second switch SW2 is closed. In order to measure the voltage value (V2) across the second resistor R2, it is also connected to both ends of the first resistor R1 and both ends of the second resistor R2. The voltage measurement circuit 3 includes a differential amplifier circuit that reduces the influence of impedance and the like, and an A / D converter that outputs a digital voltage value. The output side of the voltage measurement circuit 3 is connected to the microprocessor 2.

  In this example, the A / D converter that constitutes the voltage measuring circuit 3 is polarized as a value of 10 LSB or more at 2 A, even with the largest 245H52 type battery (nominal capacity: 176 Ah) of a 12 V monoblock battery for automobiles. A 20 V full-scale 16-bit A / D converter capable of measuring the above was used. The reason for using 10LSB or more as a standard is that, since an A / D converter usually includes an error of about 3LSB, in order to be a significant voltage measurement value, the measurement value needs to be sufficiently larger than 3LSB. . In this example, the A / D converter operates at a sampling rate of 10 μs.

  Further, the battery tester 1 sets the current value (I1) flowing through the first energization circuit (first resistor R1) and the second energization circuit (second resistor R2) through a current sensor such as the Hall element HS. A first current measurement circuit 41 and a second current measurement circuit 42 for measuring a flowing current value (I2) are provided, and the output sides of these current measurement circuits are connected to the microprocessor 2, respectively. The temperature sensor TH described above is connected to the temperature measurement circuit 5, and the output side of the temperature measurement circuit 5 is connected to the microprocessor 2. Each of the first current measurement circuit 41, the second current measurement circuit 42, and the temperature measurement circuit 5 includes an A / D converter. In this example, the A / D converters of the first current measurement circuit 41 and the second current measurement circuit 42 operate at a sampling rate of 10 μs, similarly to the A / D converter of the voltage measurement circuit 3.

  The voltage across the first resistor R1 and the second resistor R2 is measured in this way because of the error caused by the resistance in the ON state of the first switch SW1 and the second switch SW2 formed of FETs or the like. In addition, the current flowing through these resistors is measured by separate current measuring circuits because the current values flowing through the two resistors are different by one digit as will be described later. This is because the error is reduced by measuring with the measurement circuit, and consequently, an ohmic resistance component and a charge transfer resistance component of the battery 10 to be described later are accurately measured.

  The first switch SW1 and the second switch SW2 are connected to the microprocessor 2 and are controlled to be turned on and off in accordance with a signal output from the microprocessor 2.

  Further, the above-described mini printer 8, display unit 12, LCD 7, input operation unit 6, and USB terminal 11 are connected to the microprocessor 2.

  The microprocessor 2 includes a CPU that functions as a central processing unit, a RAM that functions as a work area for the CPU, a CPU program, maps and formulas described later, and data such as resistance values of the first resistor R1 and the second resistor R2. It includes a stored ROM.

  Here, the on-control time by the microprocessor 2 of the first switch SW1 and the second switch SW2 constituting the first and second energization circuits and the resistance values of the resistances of the first and second energization circuits will be described. .

1. On-control time of switch As shown in FIG. 4, the waveform which combined the pulse of 0.5ms30A and 0.5s2A was applied to the lead storage battery 80D26 for normal vehicles of JIS-D5301. The reason why the values are set to 30A and 2A will be described later (refer to “2. Resistance value of resistance of first and second energization circuits”). The resistance of an electrochemical cell is generally time-dependent, and frequency dispersion analysis of complex impedance is used for battery characteristic evaluation. As shown in FIG. 5, the imaginary part-real part impedance response of 80D26 is composed of a circular arc and a straight line extending to the right side, and the imaginary part takes a minimum value at 1 Hz, and the imaginary part becomes zero at 1 kHz. This corresponds to an electrochemical system equivalent circuit model called a generally known Randles equivalent circuit, and the resistance of the real part when the imaginary part on the high frequency side is zero is an ohmic resistance Rohm. The value of the real part at the frequency at which the imaginary part on the lower frequency side takes the minimum value is the sum of the ohmic resistance Rohm and the charge transfer resistance Ret.

  The ohmic resistance Rohm and the charge transfer resistance Ret can be expressed as Rohm = 1 kHz resistance, Ret = 1 Hz resistance-1 kHz resistance. When converted to a DC pulse, it can be expressed as Rohm = pulse width 0.5 ms resistance = (voltage before pulse−0.5 ms voltage) /0.5 ms current. The 0.5 ms current is handled as a current flowing in the battery tester 1. This is because it is assumed that the test is not performed during load discharge or during charging with the power source for charging. When testing during load discharging or charging with a charging power source, it is necessary to measure the charging / discharging current of a clamp meter or the like and add it to the 0.5 ms current. However, it is better to reduce the cost by omitting the clamp meter because it is sufficient to specify the procedure so that it is not tested during load discharge or charging with the power supply for charging. Also, Ret = pulse width 0.5 s resistance−pulse width 0.5 ms resistance. Note that specific calculation formulas for the ohmic resistance Rohm and the charge transfer resistance Ret in this embodiment will be described later.

  Referring to FIG. 5, since the slope of the curve is large in the vicinity of the minimum value, it seems that the real component of the impedance to be measured does not change much even if the frequency shifts and the measurement point slightly shifts. (To be tested) In order to accurately determine the state of the battery 10, the frequency and the current value measured at those frequencies are used using frequencies suitable for measuring the ohmic resistance Rohm and the charge transfer resistance Ret in the battery. It is desirable to estimate battery degradation using It is preferable to select a frequency at which the error is reduced when the frequency to be measured varies or the correspondence between the frequency and the impedance shifts due to battery variations.

  An index of the R real number component measurement error due to the frequency is expressed as -dR real number component / dln (frequency f), and this value is calculated based on the experimental data of FIG. 5 at each frequency, and FIG. 6 is obtained. For example, when the frequency measured in FIG. 5 is 35 and expressed by f (1), f (2),..., F (35), f (1) = 0.01, f (2) = Calculate the frequency by f (1) × 1.4678, f (3) = f (2) × 1.4678, f (35) = f (34) × 1.4678, and measure at frequency f (n) If the R real number component is expressed as R (n), −dR real number component / dln (frequency f) ≈− (R (n) −R (n−1)) / (ln (f (n)) − ln FIG. 6 can be calculated as (f (n−1))). Referring to FIG. 6, the error is small in a low frequency of 0.5 to 2 Hz (pulse width conversion 1 s to 0.25 ms) and in a high frequency region of 300 Hz to 3 kHz (pulse width conversion 1.7 ms to 0.17 ms). I understand that.

  When using it as a battery tester, it is energized with a short pulse width of 1.7 ms to 0.17 ms and a long pulse width of 1 s to 0.25 ms corresponding to the frequencies of these two regions. The ohmic resistance Rohm and the charge transfer resistance Ret of the battery may be calculated from the values.

  For this reason, in this embodiment, the on-time of the first switch SW1 by the CPU of the microprocessor 2 is set to 0.5 ms within a short pulse width, and the on-time of the second switch SW2 is set to 0.5 s within a long pulse width. Set and control these two switches to ON state at different times, more specifically, control the second switch SW2 to OFF state and the first switch SW1 to ON state with a short pulse width (0.5 ms) Immediately after, the first switch SW1 is turned off, and the second switch SW2 is controlled to be turned on with a long pulse width (0.5 s). In order to calculate the ohmic resistance Rohm and the charge transfer resistance Ret of the battery 10, it is necessary to measure the open circuit voltage of the battery 10, and the measurement timing is limited to either before or after energization by the battery tester 1. In order to avoid the influence of polarization due to the energization of the first and second energization circuits, it is preferable to energize the first and second energization circuits. Further, immediately after the first switch SW1 is controlled to be in the ON state, the second switch SW2 is controlled to be in the ON state because of the influence of the change in the remaining battery capacity compared to the reverse case or when an interval is provided between them. Because I thought it was small.

2. The resistance value of the resistance of the first and second energization circuits The current energized to the battery 10 may be continuous or single-shot multiple times, but it is intended to shorten the time and control the battery tester 1 by increasing the temperature. In order to eliminate the adverse effect on the measurement system, it is desirable to set the number of continuous waveform applications so that the temperature rise is 5K or less. In addition, since there is a possibility that an operator may continuously test a large number of batteries in a short time, it is necessary to design with a margin so that the temperature does not become abnormally high. In order to suppress the temperature rise, it is desirable that the inside of the battery tester 1 is filled with a material having a relatively large thermal conductivity and heat capacity. Examples of such a material include an epoxy resin using silicon particles as a filler. The following equation (1) can be used to approximate the upper limit of the number n of continuous waveform applications in one test.

  For example, when the waveform is 100 Hz 0A to 1A rectangular wave (0A5ms + 1A5ms), the single waveform electric quantity is 5 mC. If the number of short-time user continuous tests is 50, the inside of the tester is filled with a resin using a ceramic filler such as silicon oxide, and the battery tester heat capacity is 80 J / K, then n = 133. When this is converted into time, 133 times / 100 Hz = 1.3 seconds. This is a sufficiently short time for one test. For this reason, for example, the estimation accuracy may be increased by applying a waveform 133 times and performing an averaging process.

  If the heat generation is large, the resistance value of the resistor may fluctuate, resulting in poor current measurement accuracy. If it is severe, the parts may be damaged, or the tester surface may become hot and cannot be held by hand. For this reason, in consideration of avoiding the problem of heat generation, as described above, the current is reduced to 2 A for a pulse having a long pulse width.

  On the other hand, the current with a short pulse width of 1.7 ms to 0.17 ms was 30 A when the current suitable for detection of a deteriorated battery in a battery of various battery types specified in JIS-D5301 was 30 A. did. Whether it is suitable for detecting a deteriorated battery is determined by measuring the internal resistance by discharging various currents between a new battery and a deteriorated battery of the same standard, and detecting a current with a large difference in internal resistance between the new battery and the deteriorated battery. Judged to be suitable. From 1.7 ms to 0.17 ms 30 A, the problem of heat generation is unlikely to occur, so it was not necessary to limit the current due to heat generation with a short pulse.

  Based on the above, in the present embodiment, the first resistor R1 has a wound resistance of 0.4Ω (error accuracy 5%), and the second resistor R2 has a winding resistance of 6Ω (error accuracy 5%). Resistance was used. In these resistance values, V1 shown in FIG. 4 is about 300 mV, and V2 is about 100 mV.

<Operation>
Next, a battery state estimation routine executed by the CPU of the microprocessor 2 (hereinafter simply referred to as CPU) will be described. When the operator connects the positive and negative clip respectively to the positive and negative terminals, a voltage sensor (not shown) senses the voltage of the battery 10 and supplies the power from the built-in battery to the above-described units, and is stored in the ROM of the microprocessor 2. The battery state estimation routine is started through an initial setting process such as development of programs and data in the RAM.

  As shown in FIG. 3, in the battery state estimation routine, first, in step 102, a screen requesting input (selection) of information for specifying the type of the battery 10 is displayed on the LCD 7. Information for specifying the type of the battery 10 includes the type of the battery 10 (for example, 55D23 of the JIS-D5301 standard for a normal automobile battery, or Q55 of the SBA0101 standard of the Battery Industry Association for an ISS car battery), the battery 10 (For example, a normal car battery, an ISS car battery, a charge control car battery), and a type of a vehicle in which the battery 10 is mounted (eg, a normal car, ISS car, charge control car). .

  The operator operates, for example, a menu key of the input operation unit 6 to provide information for specifying the type of the battery 10 by any of the type of the battery 10, the type of the battery 10, and the type of the vehicle on which the battery 10 is mounted. A menu screen indicating whether to input is displayed on the LCD 7, and an enter (selection) screen that the user desires to input (select) is displayed on the LCD 7 by pressing the enter key of the input operation unit 6. For example, when the operator selects the type of the battery 10, a list screen of battery types is displayed on the input screen. The operator refers to the list screen, operates the up / down scroll key and the like to select the type of the battery 10 and presses the enter key, thereby inputting information for specifying the type of the battery 10. Similarly, when the operator selects the type of the battery 10 or the type of the vehicle on which the battery 10 is mounted, a list screen of the battery type or the type of the vehicle on which the battery is mounted is displayed. Is operated to select the type of the battery 10 and press the enter key to input information for specifying the type of the battery 10.

  Note that the type of a normal vehicle battery is defined in the JIS-D5301 standard, and the type of an ISS vehicle battery is defined in the SBA0101 standard of the Battery Industry Association. The model of the battery for charge control vehicles including regenerative charging is the same as the battery for ordinary automobiles, but since the sticker indicating that it is for charge control vehicles is attached on the upper surface, it can be confirmed that it is a charge control vehicle. .

  In addition, since the battery tester 1 has the USB terminal 11, instead of the information input method for specifying the type of the battery 10 by the LCD 7 and the input operation unit 6 as described above, the USB cable is connected to the USB terminal 11. By transmitting information for specifying the type of the battery 10 from the PC connected via the USB, the information for specifying the type of the battery 10 may be input, or the battery 10 is connected to the USB terminal 11. A USB memory storing information for specifying the type may be connected and the input operation unit 6 may be operated to input information for specifying the type of the battery 10.

  On the other hand, the CPU waits until information for specifying the type of the battery 10 is input (selected) in step 104, and when input (selected), the CPU specifies the type of the battery 10 in the next step 106. To do. At this time, for example, when information for specifying the type of the battery 10 is input (selected) by the type of the battery 10 or the type of the vehicle on which the battery 10 is mounted, the battery is referred to by referring to the corresponding table. 10 types are specified (for example, when Q55 is selected as the type of the battery 10 or when an ISS vehicle is selected as the type of the vehicle on which the battery is mounted, the battery is specified as an ISS vehicle battery).

  Next, at step 108, the CPU captures the open circuit voltage value (OCV) of the battery 10 output from the voltage measurement circuit 3. Note that the first switch SW1 and the second switch SW2 remain off. In step 108, the temperature value output from the temperature measurement circuit 5 is also captured.

  Next, in step 110, the first switch SW1 is controlled to be on for 0.5 ms. In the next step 112, while the first switch SW1 is controlled to be on, the voltage measurement circuit 3 The voltage value (V1) across the output first resistor R1 and the current value (I1) flowing through the first resistor R1 output from the first current measurement circuit 41 are captured. In this state, the second switch SW2 remains off.

  Next, in step 114, the first switch SW1 is controlled to be in an off state and the second switch SW2 is controlled to be in an on state for 0.5 s. In the next step 116, the second switch SW2 is controlled to be in an on state. In between, the both-ends voltage value (V2) of the 2nd resistance R2 output from the voltage measurement circuit 3 and the current value (I2) which flows into the 2nd resistance output from the 2nd current measurement circuit 42 are taken in. When this capture is completed, the second switch SW2 is controlled to be in an OFF state.

Next, in step 118, the measured open circuit voltage value (OCV), the voltage value (V1) across the first resistor R1, the current value (I1) flowing through the first resistor R1, and the both ends of the second resistor R2 A cold cranking amperage (CCA) value is calculated (calculated) from the voltage value (V2) and the current value (I2) flowing through the second resistor R2 by the following equation (2). As described above, since OCV, V1, I1, V2, and I2 are measured every 10 μs, the measured average values may be OCV, V1, I1, V2, and I2. When calculating the CCA, the CPU refers to the Rohm to Rohm ^* conversion map and the Ret to Ret ^* conversion map stored in the ROM and expanded in the RAM.

  Next, in step 120, the state of the battery 10 is estimated by applying the measured OCV and the calculated CCA to the determination map corresponding to the battery type specified in step 106.

  The determination map of this example defines the relationship between the OCV, the CCA, and the battery state. FIG. 7 shows a normal vehicle battery determination map, and FIG. 8 shows the ISS vehicle and charge control vehicle battery. An example of a determination map is shown. In these determination maps, a new battery should ideally be positioned at the position of 100% on the vertical axis in FIGS. 7 and 8, but as it deteriorates, the position of 75% is determined to be a good / replaceable threshold. Set to value. However, the threshold value for determining good / required replacement is not limited to this.

  In addition, these determination maps include a good area and a required charging area that are adjacent to the state of the battery via a required charging threshold. In the vehicle battery determination map (FIG. 7), the required charging threshold is 12.6 V, whereas in the ISS vehicle and charge control vehicle battery determination map (FIG. 8), the required charging threshold is required. The value is set to 12.4V. In an ISS vehicle or a charge control vehicle including regenerative charging, a battery is used in a state where the SOC is low. Therefore, when the OCV of the required charging threshold is 12.6 V, which is the same as that of a normal automobile battery, the determination of required charging frequently occurs. Normally, a battery for an automobile has a short life when used at a low SOC, but a battery for an ISS car or a charge control car is designed so as not to cause a problem even when used at a low SOC. For this reason, it is possible to avoid erroneous determination of required charging by lowering the required charging threshold value to about 12.4V.

  Furthermore, in the determination map of this example, the battery state is classified into five types of “deterioration cell replacement”, “good charging required”, “good”, “retest after charge”, and “deterioration replacement”. , More or less may be classified. In the determination maps shown in FIGS. 7 and 8, the OCV is 11.8 V when the diagonal line defining “retest after charge” and “deterioration replacement” is extended to CCA = 0%.

  In the next step 122, the state of charge (SOC) and health level (SOH) of the battery 10 are estimated and displayed on the touch panel. That is, as shown in FIG. 9, the charge state of the battery 10 is applied by applying the open circuit voltage value (OCV) measured in step 108 to a relationship map that defines the relationship between the open circuit voltage (OCV) and the state of charge (SOC). (SOC) is estimated. Further, as shown in FIG. 10, the health degree (SOH) of the battery 10 is estimated by applying the actually measured Ret to the second relation map that defines the relation between the charge transfer resistance Ret and the health degree (SOH) in the ROM. To do. Ohmic resistance and SOH are not generally compatible properties, but charge transfer resistance depends on the effective surface area of the electrode and the concentration of electrode reactive species (sulfuric acid) in the electrolyte. In a battery system in which the effective surface area and the electrode reactive species (sulfuric acid) concentration vary with (SOC), the charge transfer resistance corresponds to SOH. Since the remaining capacity is a one-to-one correspondence with SOH, the remaining capacity can be estimated. In estimating these SOH and SOC, it is preferable to correct the temperature to SOH and SOC at a predetermined temperature.

  Further, in step 122, as a result of the estimation (test) of the state of the battery 10 by the battery tester 1, the green LED of the display unit 12 is displayed when the battery 10 is in a good state, and when the battery 10 is in a required charging state. The yellow LED of the display unit 12 is turned on for a predetermined time (for example, 2 minutes), respectively, when the battery 10 is in a replacement required state. Further, when there is an instruction to output the measurement result or the estimation result to the mini printer 8 via the input operation unit 6, the instruction is output (printed) according to the instruction. When the process in step 122 ends, the battery state estimation routine ends.

(Effects etc.)
Next, functions and effects of the battery tester 1 of the present embodiment will be described.

  In the battery tester 1 of the present embodiment, the ROM is a map in which the relationship between the OCV, the CCA, and the battery state is defined. A plurality of determination maps (see FIGS. 7 and 8) including a charging area and having at least a required charging threshold value corresponding to the type of battery are stored, and these determination maps are developed in the RAM. In accordance with the information for specifying the type of battery input (selected) by the input operation unit 6, a determination map having different charging threshold values corresponding to the type of battery is switched (corresponding to the type of battery). The determination state is specified, and the state of the battery is estimated (steps 106 and 120). For this reason, it is possible to avoid erroneous determination of required charging even for batteries for ISS vehicles and charge control vehicles, and to appropriately determine the state of the battery 10.

  Further, according to the battery tester 1 of the present embodiment, the microprocessor 2 has the first pulse width within which the frequency error is almost minimized when calculating the ohmic resistance Rohm and the charge transfer resistance Ret of the battery 10. The switch SW1 and the second switch SW2 are controlled to be turned on. For this reason, the microprocessor 2 measures the open circuit voltage value (OCV) of the battery 10 and the first resistor R1 measured in a state where the first switch SW1 is controlled to be on with a short pulse width (0.5 ms). The ohmic resistance component Rohm of the battery 10 can be properly detected from the both-end voltage value (V1) and the current value (I1) flowing through the first resistor R1 (see Equation (2)), and this ohmic resistance component Rohm, The open circuit voltage value (OCV) of the battery 10, the voltage value (V2) across the second resistor R2 measured with the second switch SW2 controlled to be on with a long pulse width (0.5 s), and the second voltage Since the charge transfer resistance Ret of the battery 10 can be properly detected from the current value (I2) flowing through the resistor 2 (see equation (2)), the state of the battery 10 can be accurately estimated. .

  Further, according to the battery tester 1 of the present embodiment, the energization pulse flowing through the first and second energization circuits is 1 s or less even with a long pulse width (0.5 s), and the energization current (30 A) also simulates engine start. Since it is not necessary to make the current so large, heat generation can be suppressed, the first resistance R1 and the second resistance R2 can be reduced, and the overall size of the apparatus can be reduced.

  Furthermore, according to the battery tester 1 of the present embodiment, the microprocessor 2 immediately after the second switch SW2 is turned off and the first switch SW1 is turned on with a short pulse width (0.5 ms). Since the first switch SW1 is turned off and the second switch SW2 is controlled to be turned on with a long pulse width (0.5 s), the influence of the remaining capacity of the battery 10 can be reduced, and the state of the battery 10 can be accurately determined. Can be estimated well.

  Further, according to the battery tester 1 of the present embodiment, the microprocessor 2 includes the open circuit voltage value (OCV), the voltage value across the first resistor R1 (V1), and the current value (I1) flowing through the first resistor R1. ) And the voltage value (V2) across the second resistor R2 and the current value (I2) flowing through the second resistor R2, the charge transfer resistance value Ret of the battery 10 is calculated, and the calculated charge transfer resistance value Ret The health level (SOH) of the battery 10 is estimated by applying it to a relationship map that defines the relationship between the charge transfer resistance value Ret and the health level of the battery 10 stored in advance in the ROM, and the open circuit voltage value (OCV) is calculated. The state of the battery 10 can be detected in detail because the state of charge (SOC) of the battery 10 is estimated by applying it to a relationship map that defines the relationship between the open circuit voltage and the state of charge.

  Furthermore, according to the battery tester 1 of the present embodiment, the calculated ohmic resistance Rohm and the charge transfer resistance Ret are corrected to the values at −18 ° C. based on the temperature values measured by the temperature measurement circuit 5 having the temperature sensor. Therefore, the cold cranking amperage value can be calculated with high accuracy, and as a result, the state of the battery 10 can be estimated appropriately.

  In the present embodiment, a plurality of determination maps that define the relationship among the OCV, the CCA, and the state of the battery are exemplified, but the present invention is not limited to this. For example, SOC may be used instead of OCV. The conversion from OCV to SOC can be performed using, for example, the relationship map shown in FIG. Further, SOH or the internal resistance (Ir) of the battery may be used instead of CCA. As described above, there is a correlation between the charge transfer resistance value Ret and the health level (SOH) (see also FIG. 10), and it is known that there is a correlation between the SOH and the internal resistance (Ir). SOH and Ir can be obtained from the resistance value Ret. Therefore, for example, when using a plurality of determination maps that define the relationship between SOC, SOH or Ir, and the battery state, the first relationship map that defines the relationship between OCV and SOC, the charge transfer resistance, A second relationship map that defines the relationship with SOH or Ir is also stored in the ROM, and the SOC value is calculated by applying the measured OCV to the first relationship map, and the charge calculated by Equation (2) is used. The value of SOH or Ir is calculated by applying the movement resistance value to the second relationship map, and the state of the battery 10 is estimated by applying the calculated SOC and SOH or Ir to the determination map corresponding to the type of the battery 10 You may make it do. Furthermore, although CCA (%) was illustrated in this embodiment, CCA (A) may be used instead.

  Moreover, in this embodiment, although the example which displays the estimation result of the state of the battery 10 by the battery tester 1 by lighting LED of the display part 12 was shown, this invention is not restricted to this, For example, with LCD7 You may make it display. Furthermore, in this embodiment, in order to improve the determination accuracy of the battery tester 1, the first and second energization circuits are exemplified. However, the present invention is not limited to this, and the determination is performed using one energization circuit. It can also be applied to battery testers.

  Furthermore, in this embodiment, as shown in FIGS. 7 and 8, the determination map for the entire area is illustrated, but a table in which both OCV and CCA are discrete values is used as the determination map, and the CPU apportions the numerical value between the discrete values. You may make it complement by.

  In the present embodiment, the voltage measurement circuit 3 is single in consideration of cost, but the present invention is not limited to this, and an open circuit voltage measurement unit that measures the open circuit voltage of the battery 10; You may make it comprise the three voltage measurement parts of the 1st voltage measurement part which measures the both-ends voltage of 1st resistance R1, and the 2nd voltage measurement part which measures the both-ends voltage of 2nd resistance R2.

  In the present embodiment, in order to improve current measurement accuracy, the first current measurement circuit 41 that measures the current flowing through the first resistor R1 and the second current measurement circuit that measures the current flowing through the second resistor R2 are used. For example, the battery 10 when the current sensor is provided between the positive clip and the second switch SW2 and the first switch SW1 and the second switch SW2 are closed is illustrated. The current flowing through the current may be measured by one current measurement circuit. In this case, the current value flowing through the first resistor R1 and the second resistor R2 may be calculated in consideration of the resistance when the first switch SW1 and the second switch SW2 are in the on state.

  Furthermore, in this embodiment, in order to measure the temperature of the battery 10, the temperature sensor was fixed to the positive clip, and the temperature of the positive external terminal of the battery 10 was measured as the temperature of the battery 10. The temperature of the battery 10 may be measured by being fixed to the battery 10. In this embodiment, the operator connects the positive and negative clip to the positive and negative terminals, respectively, so that the voltage sensor (not shown) senses the voltage of the battery 10 and automatically supplies the power from the built-in battery to each unit. In this example, the battery state estimation routine is started. However, a power switch for turning on or off the battery tester 1 is provided, and the operator connects the positive and negative clips to the positive and negative terminals, and turns on the power switch. Thus, the battery state estimation routine may be started.

  Since the present invention provides a battery tester capable of properly determining the state of a battery for an ISS vehicle or a charge-controlled vehicle including regenerative charging, it contributes to the manufacture and sale of the battery tester. Have potential.

1 battery tester 2 microprocessor (control means, storage means, part of acquisition means)
3 Voltage measurement circuit (part of voltage measurement means)
6 Input operation part (input means)
7 Liquid crystal display device (display means)
8 Mini printer 10 Battery 11 USB terminal (part of acquisition means)
12 Display section (second display means)
41 First current measurement circuit (part of current measurement means)
42 Second current measurement circuit (part of current measurement means)
R1 first resistance (part of constant resistance)
R2 Second resistance (part of constant resistance)
SW1 first switch SW2 second switch

Claims (10)

An energization circuit having a constant resistance and connected in parallel to the battery;
Voltage measuring means for measuring an open circuit voltage (OCV) of the battery and a voltage across a constant resistance of the energization circuit;
Current measuring means for measuring a current flowing in the energization circuit;
Input means for inputting information for identifying the type of the battery;
Storage means for storing the judgment map;
Control means for estimating the state of the battery using a determination map stored in the storage means;
With
The storage means is a map that defines the relationship between the battery's OCV or state of charge (SOC), the battery's cold cranking amperage (CCA) or health (SOH) or internal resistance (Ir), and the state of the battery. And storing a plurality of determination maps including a good area and a required charging area that are adjacent to each other via a required charging threshold in the state of the battery, and differing at least the required charging threshold according to the type of battery. And
The control means determines the CCA or SOH of the battery from the OCV of the battery and the voltage across the constant resistance measured by the voltage measurement means, and the value of the current flowing through the energization circuit measured by the current measurement means. Alternatively, the value of Ir is calculated, and if necessary, the value of the SOC of the battery is calculated from the battery OCV measured by the voltage measuring unit, and the type of the battery input by the input unit is specified. The determination map is switched according to the information for the purpose, and the state of the battery is estimated by applying the measured OCV or the calculated SOC and the calculated CCA, SOH, or Ir to the switched determination map. ,
A battery tester characterized by that.   2. The battery tester according to claim 1, wherein the information for specifying the type of battery includes at least one of a battery type, a battery type, and a vehicle type on which the battery is mounted.   The battery type includes at least one of an idle stop start (ISS) vehicle battery and a charge control vehicle battery, and the vehicle type on which the battery is mounted includes at least one of an ISS vehicle and a charge control vehicle. The battery tester according to claim 2, wherein:   4. The display device according to claim 1, further comprising display means for displaying a screen for allowing an operator to select information for specifying the type of battery by the input means. 5. Battery tester.   The information processing device further comprises acquisition means for acquiring information for specifying the battery type from the outside, and the control means is configured to determine the battery according to the information for specifying the battery type acquired by the acquisition means. The state of the battery is estimated by applying the measured OCV or the calculated SOC and the calculated CCA, SOH, or Ir to the switched determination map. The battery tester according to claim 4.   The control means is configured to determine an ohmic resistance of the battery from an OCV of the battery measured by the voltage measuring means and a voltage across the constant resistance, and a value of a current flowing through the energization circuit measured by the current measuring means. And calculating a value of CCA, SOH or Ir of the battery from the OCV of the battery measured by the voltage measuring means, the calculated ohmic resistance value and the charge transfer resistance value. 6. The battery tester according to claim 1, wherein a value of the SOC of the battery is calculated from an OCV of the battery measured by the voltage measuring unit as necessary.   The plurality of determination maps stored in the storage means are maps that define the relationship between the OCV, the CCA, and the state of the battery, and the control means includes the measured OCV and the calculated ohmic resistance. The CCA value is calculated from the value and the charge transfer resistance value, and the state of the battery is estimated by applying the measured OCV and the calculated CCA value to the switched determination map. 6. The battery tester according to 6.   The plurality of determination maps stored in the storage means are maps that define the relationship between the SOC, SOH or Ir, and the state of the battery, and the storage means defines the relationship between the battery OCV and the SOC. A first relationship map and a second relationship map that defines a relationship between the charge transfer resistance of the battery and SOH or Ir are further stored, and the control means stores the measured OCV in the first relationship. The SOC value of the battery is calculated by applying it to the map, and the SOH or Ir value of the battery is calculated by applying the calculated charge transfer resistance value to the second relationship map, and the switched determination map is used. The battery test according to claim 6, wherein the state of the battery is estimated by applying the calculated SOC and SOH or Ir values. .   9. The battery tester according to claim 1, further comprising second display means for displaying a result of estimation of the state of the battery by the control means. 10.   The second display means includes an LED for indicating that the battery is in a good state, an LED for indicating that the battery is in a required charge state, and the battery in a required replacement state. The battery tester according to claim 9, further comprising an LED for displaying.

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