JP6507989B2 - Battery monitoring device - Google Patents

Description

  The present invention relates to a battery monitoring device that monitors the presence or absence of an abnormality in a battery pack.

  In Patent Document 1, a battery block is configured as a series connection of a plurality of battery cells (unit batteries). A plurality of battery blocks are connected via a conductive member to constitute a battery pack. Flying capacitors are configured to be switched and connected to the electric paths on both sides of the battery cells constituting each battery block, and the voltage of each battery cell is determined from the charging voltage of the flying capacitor charged with the voltage of each battery cell. It is supposed to be detected.

  In the above configuration, it is necessary to detect an abnormality (breakage or the like) of the conductive member between the battery blocks. Therefore, in Patent Document 1, a bypass path having a Zener diode is connected in parallel to a pair of electric paths connected to both sides of a conductive member between battery blocks. Then, in a state where the flying capacitors are connected to a pair of electric paths connected to both ends of the conductive member between the battery blocks, a discharge current from the flying capacitors is allowed to flow through the pair of electric paths. At this time, if no abnormality occurs in the conductive member between the battery blocks, the discharge current flows through the conductive member. On the other hand, if an abnormality occurs in the conductive member between the battery blocks, the discharge current will flow through the bypass path.

  When the discharge current of the flying capacitor flows to the bypass path side, a breakdown voltage (Zener voltage) of the Zener diode is generated. Therefore, when the conductive member between the battery blocks is normal, if there is an abnormality in the conductive member, the potential difference between both ends of the bypass path and the voltage between the terminals of the flying capacitor at the time of discharge may be largely deviated. . Thus, based on the fact that the potential difference at both ends of the bypass path or the voltage across the flying capacitors differs depending on the presence or absence of the conductive member between the battery blocks, the presence or absence of the conductive member between the battery blocks is determined. Can.

2015-83960 gazette

  However, in the configuration of Patent Document 1, in order to detect an abnormality in the conductive members provided between the battery blocks, it is necessary to provide a member such as a bypass path for each conductive member between the battery blocks, and this is accompanied by an increase in the number of parts. An inconvenience occurs.

  Moreover, connecting a plurality of battery cells constituting the battery block via a conductive member is also assumed. However, providing a member such as a bypass path as shown in Patent Document 1 in order to detect an abnormality of the conductive member in the battery block leads to an increase in the number of parts.

  The present invention has been made in view of the above, and has as its main object to provide a battery monitoring device capable of monitoring the state of a battery assembly with a simple configuration.

  The present invention relates to the presence or absence of abnormality in an assembled battery (10) configured by connecting in series a plurality of battery blocks (11) configured by a series connection of a battery cell (CE) and a conductive member (SP). A battery monitoring device for monitoring, wherein capacitors (22) switchably connected in parallel to respective ones of the battery blocks and one current of the battery cell instead of the conductive member when the conductive member is abnormal The current limiting element (D) connected in parallel to the conductive member so as to flow in the direction, the capacitance component (C) connected in parallel to the conductive member, and the voltage of the battery block to be measured A plurality of battery cells and the capacitor are connected in parallel so that the capacitor is charged with a large voltage, and a charge processing unit (30) performing charge processing for charging the capacitor; and the measurement pair A discharge processing unit (30) for performing a discharge process of discharging the charge of the capacitor with respect to the battery block to be measured by parallel-connecting the battery block and the capacitor after the charge process; An abnormality determination unit (30) that determines the presence or absence of an abnormality of the conductive member in the battery block to be measured based on the voltage of the capacitor.

  According to the present invention, the battery block is configured as a series connection of the battery cell and the conductive member. Then, a plurality of battery blocks are connected in series to constitute an assembled battery. Then, capacitors are switchably connected in parallel to each of the battery blocks. Further, instead of the conductive member when there is an abnormality in the conductive member, a current limiting element and a capacitive component for flowing the current of the battery block in one direction are connected in parallel to the conductive member in the battery block.

  In the above configuration, a plurality of battery cells and a capacitor are connected in parallel to charge the capacitor so that the capacitor is charged with a voltage larger than the voltage of the battery block to be measured. Under the present circumstances, even if abnormality (broken wire etc.) has arisen in the electrically-conductive member in a battery block, since an electric current flows through a current limiting member, a capacitor can be charged with the voltage of a battery block.

  Thereafter, the battery block to be measured and the capacitor are connected in parallel to discharge the charge of the capacitor to the battery block to be measured. At this time, if there is no abnormality in the conductive member in the battery block to be measured, the voltage of the capacitor is up to the voltage of the battery block to be measured by the discharge current flowing only through the battery cell and the conductive member in the battery block. descend. On the other hand, if an abnormality occurs in the conductive member in the battery block to be measured, no current flows in the conductive member in the abnormal part, and a discharge current flows in the capacitive component connected in parallel to the conductive member. At this time, the voltage generated in the capacitive component causes the voltage of the capacitor to drop only to a voltage higher than the voltage of the battery block to be measured.

  As described above, after the capacitor is charged with a voltage larger than that of the battery block to be measured, and then the capacitor is discharged by connecting the battery block to be measured and the capacitor, the conductive member in the battery block Depending on the presence or absence of abnormality, a difference occurs in the voltage of the capacitor. By utilizing this, the presence or absence of abnormality of the conductive member in the battery block to be measured can be detected with a simple configuration.

The figure which shows the circuit structure of a battery monitoring system. The figure which shows the battery block and the circuit structure of a periphery. Explanatory drawing of the charging / discharging process of the capacitor by a control apparatus. The figure which shows the relationship between the presence or absence of abnormality of a battery block, and the charge process of a capacitor. The figure which shows the relationship between the presence or absence of abnormality of a battery block, and the discharge process of a capacitor. The flowchart of the abnormality determination process of a battery block. The figure which shows the circuit structure of the battery block of a modification example.

  Hereinafter, embodiments of the present invention will be described based on the drawings. In the following embodiments, parts identical or equivalent to each other are denoted by the same reference numerals in the drawings. The assembled battery of the present embodiment is used as a power supply for supplying electric power to a motor for traveling a vehicle (traveling motor) through an inverter or the like.

First Embodiment
As shown in FIG. 1, the battery monitoring system 100 includes a battery pack 10, a battery monitoring device 20, and a control device 30.

  The battery assembly 10 is configured as a series connection of a plurality of battery blocks 11. FIG. 1 shows an example in which the battery pack 10 is configured as a series connection of five battery blocks 11 (11a to 11e). Besides this, the battery assembly 10 can be configured as a series connection of an arbitrary number of battery blocks.

  Here, the configuration of the battery block 11 will be described. FIG. 2 shows an example of the battery block 11a. In addition, since the structure of the other battery blocks 11b-11e is the same as that of the battery block 11a, detailed description is abbreviate | omitted. The battery block 11a is configured by connecting a plurality of unit batteries UB and a conductive member SP in series. The unit cell UB is configured using a battery cell CE as a minimum unit of charge and discharge. The battery cell CE is a lithium ion storage battery, a lead storage battery, or the like. Further, in the example of FIG. 2, the unit battery UB is configured by a plurality of battery cells CE, but the unit battery UB may be configured by a single battery cell CE.

  The conductive member SP is, for example, a wire, and is used to connect adjacent unit cells UB. Further, a capacitor C is connected in parallel to each of the unit cell UB and the conductive member SP as a conventional noise countermeasure.

  Returning to the description of FIG. 1, the battery monitoring device 20 includes a resistor R, an input switch 21, a capacitor 22, an output switch 23, a voltage detection unit 24, and a monitoring IC 25. The battery pack 10 is connected via detection lines L1 to L10 provided at the end of the block 11.

  Of the detection lines L1 to L10, odd-numbered detection lines Li (i = 1, 3, 5, 7, 9) are connected to the high voltage side of each battery block 11, and to the low voltage side of each battery block 11. Even-numbered detection lines Lj (j = 2, 4, 6, 8, 10) are connected.

  Moreover, the resistor R is provided in each of the detection lines L1 to L10. The input switch 21 is provided between the resistor R and the capacitor 22. The input switch 21 has switches SW1 to SW10 individually provided on the detection lines L1 to L10.

  As the capacitor 22, one having a capacity capable of being charged by the voltages of the plurality of battery blocks 11 is used. In the present embodiment, the capacitor 22 is configured as a series connection of two capacitors. This makes it possible to suppress the withstand voltage of each capacitor. The capacitor 22 may be configured by at least one capacitor, or may be configured as a series connection of two or more capacitors. It is assumed that the capacitor C having a smaller capacity than the capacitor 22 is selected.

  An odd numbered switch SWi (i = 1, 3, 5, 7, 9) of the input side switch 21 is connected to the positive electrode side (+) of the capacitor 22. The even-numbered second switch SWj (j = 2, 4, 6, 8, 10) of the input-side switch 21 is connected to the negative electrode side (−) of the capacitor.

  Further, the capacitor 22 is connected to the voltage detection unit 24 via the output side switch 23. The output side switch 23 includes switches SWA and SWB. The switch SWA is connected to the positive electrode side (+) of the capacitor 22, and the switch SWB is connected to the negative electrode side (−) of the capacitor 22.

  The voltage detection unit 24 includes a differential amplification circuit, a microcomputer (microcomputer), and the like, and converts the charging voltage of the capacitor 22 into a digital signal readable by the control device 30.

  The monitoring IC 25 detects the state of each battery block 11. In FIG. 1, the monitoring ICs 25a to 25e are individually provided for the battery blocks 11a to 11e. Here, the configuration of the monitoring IC 25 will be described in detail using the example of the monitoring IC 25 a of FIG. 2.

  The monitoring IC 25a is connected to the battery block 11a via an electric path EP provided on the high voltage side and the low voltage side of each battery cell CE in the battery block 11a. Further, in order to prevent an abnormal current (overcurrent) from flowing in the monitoring IC 25 when the conductive member SP in the battery block 11 a breaks in the monitoring IC 25 a, a diode as a current limiting element is conventionally used. D is built in. The diode D is connected to a pair of electrical paths EP provided on both sides of the conductive member SP in the battery block 11a. Specifically, the anode of the diode D is connected to the electric path EP on the low potential side, and the cathode of the diode D is connected to the electric path EP on the high potential side.

  Thus, only the flow of current in one direction from the low potential side to the high potential side is permitted through the pair of electric paths EP connected to both sides of each conductive member SP, and the flow of current in the opposite direction is It is cut off. As a result, it is possible to suppress an overcurrent from flowing into the monitoring IC 25a.

  Further, when the conductive member SP in the battery block 11a is abnormal due to the diode D being connected to both ends of the conductive member SP in the battery block 11a, the diode is substituted for the abnormal part of the conductive member SP. Since the current flows through D, the capacitor 22 can be charged regardless of the presence or absence of abnormality of the conductive member SP. Although a diode is used as a current limiting element in FIG. 2, various semiconductor elements capable of restricting the flow of current in the monitoring IC 25 in one direction can be used as the current limiting element. . In addition, since the configuration of the other monitoring ICs 25b to 25e is the same as that of the monitoring IC 25a, the detailed description here is omitted.

  Returning to the description of FIG. 1, the control device 30 is a microcomputer configured to include a CPU, a memory, and the like, and performs various processes in accordance with a program stored in the memory. For example, the control device 30 switches and connects each battery block 11 to the capacitor 22 by switching the open state (off) and the closed state (on) of the switches SW1 to SW10 of the input side switch 21. Further, control device 30 performs voltage detection processing for detecting the voltage of each battery block 11.

  The voltage detection process will be described in detail. First, with the output-side switch 23 turned off, the control device 30 performs the switch SWi (i = 1, 3, 5) provided on the high voltage side of any of the battery blocks 11. , 7, 9) and SWj (j = 2, 4, 6, 8, 10) provided on the low voltage side are switched on to connect the battery block 11 and the capacitor 22. When the battery block 11 and the capacitor 22 are connected, the capacitor 22 is charged by the voltage of the battery block 11. When charging of the capacitor 22 is completed, the input switch 21 is turned off and the output switch 23 is turned on. Thereby, the voltage of the capacitor 22 input to the voltage detection unit 24 is converted into a digital signal. Then, the control device 30 reads the voltage after conversion by the voltage detection unit 24 to detect the voltage of the battery block 11 to be measured in which the capacitor 22 is charged.

  Further, control device 30 performs abnormality determination processing to determine whether or not there is an abnormality in conductive member SP in battery block 11. In addition, disconnection of conductive member SP, a fastening failure of a bolt, etc. are mentioned as abnormalities of conductive member SP. Besides, in the case where the conductive member SP is connected to the battery block 11 via a connector (not shown), it is assumed that the connection failure of the connector is included in the abnormality of the conductive member SP.

  Then, when there is an abnormality in the conductive member SP in the battery block 11, there is a possibility that the influence is exerted on the monitoring IC 25 connected to the battery block 11, so that the abnormality in the conductive member SP in the battery block 11 is detected. Need to However, adding a new configuration to detect abnormality of the conductive member SP in the battery block 11 leads to an increase in the number of parts and an increase in cost.

  By the way, in the case where the conductive member SP in the battery block 11 is abnormal, and in the case where the conductive member SP in the battery block 11 is not abnormal, the capacitor 22 is used when the control device 30 performs the following process. It turned out that a difference arises in the voltage value detected. Here, processing by the control device 30 will be described with reference to FIGS. 1 and 3 to 5.

  First, the control device 30 acquires the voltage of the battery block 11 to be measured as a reference voltage (first process P1 in FIG. 3). Specifically, the control device 30 first selects the battery block 11 to be measured. As the battery block 11 to be measured, one battery block 11 may be selected, or a plurality of adjacent battery blocks 11 may be selected together. Then, the battery block 11 to be measured and the capacitor 22 are connected, and the capacitor 22 is charged with the voltage of the battery block 11 to be measured.

  Here, an example in which the battery block 11a is selected as the battery block 11 to be measured will be described. In this case, as shown in FIG. 4, if no abnormality occurs in the conductive member SP in the battery block 11a, a charging current flows only through each battery cell CE and the conductive member SP in the battery block 11a (path A1 ). On the other hand, if an abnormality occurs in the conductive member SP in the battery block 11a, the charging current flows through the diode D instead of the conductive member SP in the abnormal part of the conductive member SP (path A2) .

  That is, in the first process P1, the voltage of the capacitor 22 is charged to the voltage of the battery block 11 to be measured regardless of the presence or absence of abnormality of the conductive member SP in the battery block 11a (see FIG. 3). Then, control device 30 obtains the charging voltage of capacitor 22 as reference voltage VB.

  Next, control device 30 performs a charging process of charging capacitor 22 with a voltage larger than the voltage of battery block 11a to be measured (second process P2 in FIG. 3). For example, in FIG. 1, the switches SW7 and SW10 are switched on to charge the capacitor 22 with the voltage of the series connected body of the battery blocks 11d and 11e. As described above, by connecting the battery blocks 11 and the capacitors 22 in a number larger than the number of the battery blocks 11 a to be measured, the capacitors 22 can be charged with a voltage larger than the voltage of the battery blocks 11 a to be measured. it can.

  Next, the capacitor 22 after the charging process and the battery block 11a to be measured are connected to perform the discharging process of the capacitor 22 (third process P3 in FIG. 3). That is, the charging voltage of the capacitor 22 is higher than the voltage of the battery block 11a to be measured due to the charging performed in the second process P2. Therefore, when the battery block 11a and the capacitor 22 are connected, the charge is discharged from the capacitor 22 to the battery block 11a.

  Under the present circumstances, as shown in FIG. 5, if abnormality does not arise in the electrically-conductive member SP in the battery block 11a, discharge current will flow through each battery cell CE and electrically-conductive member SP (pathway A3). In this case, the discharge ends when the voltage of the capacitor 22 decreases to the voltage of the battery block 11a.

  On the other hand, if the conductive member SP in the battery block 11a is abnormal, no discharge current flows through the broken portion of the conductive member SP, and the discharge current is transmitted to the capacitor C connected in parallel with the conductive member SP at the broken portion. It will flow (path A4). In this case, the discharge is completed before the voltage of the capacitor 22 decreases to the voltage of the battery block 11a due to the voltage generated in the capacitor C connected in parallel to the conductive member SP at the disconnection point.

  That is, if no abnormality occurs in the conductive member SP in the battery block 11a, the voltage of the capacitor 22 and the reference voltage VB become substantially equal. On the other hand, if an abnormality occurs in the conductive member SP in the battery block 11a, the voltage of the capacitor 22 becomes higher than the reference voltage VB (see FIG. 3).

  So, in this embodiment, when the said process is performed, according to the presence or absence of abnormality of electroconductive member SP in the battery block 11, the detected value of the voltage of the capacitor 22 changes, and the conduction in the battery block 11 is carried out. It is determined whether there is an abnormality in the member SP.

  For example, as shown in FIG. 3, the threshold value Th is set based on the reference voltage VB acquired in the first process P1. For example, the threshold Th is set to a value obtained by adding a predetermined voltage error α to the reference voltage VB. Then, if the voltage of the capacitor 22 at the time of performing the third process P3 after the second process P2 is smaller than the threshold Th, it is determined that no abnormality occurs in the conductive member SP in the battery block to be measured. On the other hand, if the voltage of the capacitor 22 after the execution of the third process P3 is larger than the threshold value Th, it is determined that the conductive member SP in the battery block to be measured has an abnormality.

  If the second processing P2 and the third processing P3 are alternately repeated if there is an abnormality in the conductive member SP in the battery block 11 to be measured, they are connected in parallel to the conductive member SP at the disconnection point. The voltage of the capacitor C gradually rises, and the difference between the voltage of the capacitor 22 and the threshold value Th after the implementation of the third process P3 is expanded.

  Therefore, in the present embodiment, on the condition that the second process P2 and the third process P3 are repeated a predetermined number of times or more for the battery block 11 to be measured, the conductive member SP in the battery block 11 to be measured is Determine if there is an abnormality.

  In the case where the second process P2 and the third process P3 are alternately repeated in a state where the conductive member SP in the battery block 11 is abnormal, a battery block to be measured in the battery block 11 used in the second process P2 When 11 is selected, the voltage of the capacitor C connected in parallel to the conductive member SP at the disconnection point is reset to 0V. That is, the electric charge of the capacitor C connected in parallel to the conductive member SP at the disconnection point is discharged in the second process P2 for charging the capacitor 22, and the voltage of the capacitor C connected in parallel to the conductive member SP at the disconnection point Is returned to 0V. Therefore, in the present embodiment, when the capacitor 22 is charged in the second process P2, the battery block 11 to be measured is not selected.

  Next, the procedure of the abnormality determination process of the present embodiment will be described using the flowchart of FIG. This process is repeatedly performed by control device 30 for each battery block 11.

  First, the first process S1 of acquiring the reference voltage VB is performed in S11 to S12. In the first process S1, first, the battery block 11 to be measured is selected (S11). In the present process, for example, the battery block 11 for which the abnormality determination has not been performed is selected. Alternatively, the battery block 11 to be measured may be selected in accordance with a predetermined sequence.

  Next, the reference voltage VB of the battery block 11 selected in S11 is acquired (S12). This process is implemented by reading the charging voltage of the capacitor 22 charged by the battery block 11 to be measured.

  Next, a second process P2 of charging the capacitor 22 with a voltage higher than the reference voltage VB is performed (S13). In this process, the capacitor 22 is charged in a state where the battery block 11 other than the battery block 11 to be measured is a plurality of adjacent battery blocks 11 and the capacitor 22 are connected. At this time, the number of battery blocks 11 to be selected is made to be larger than the number of battery blocks 11 to be measured.

  Next, a third process P3 for discharging the capacitor 22 is performed (S14). In this process, the battery block 11 to be measured and the capacitor 22 are connected in parallel. Next, it is determined whether the discharge process for the battery block to be measured has been repeatedly performed a predetermined number of times or more (S15). When S15 is denied, it returns to S13.

  When S15 is affirmed, it is determined whether the voltage (remaining voltage) of the capacitor 22 is smaller than the threshold value Th (S16). If it is determined in S16 that the voltage of the capacitor 22 is smaller than the threshold Th, no abnormality occurs in the conductive member SP in the battery block 11 to be measured, that is, the conductive member SP in the battery block 11 is normal. It judges (S17). If it is determined in S16 that the voltage of the capacitor 22 is larger than the threshold Th, it is determined that an abnormality has occurred in the conductive member SP in the battery block 11 to be measured (S18).

  Next, an example of execution of the above process will be described with reference to FIGS. Here, it is assumed that the battery block 11a is selected as the battery block 11 to be measured. In the second process P2, it is assumed that battery blocks 11d and 11e are selected as the battery block 11 connected to the capacitor 22. Then, it is assumed that one of the plurality of conductive members SP in the battery block 11a to be measured is disconnected.

  First, the reference voltage VB of the battery block 11a is acquired by performing the first process P1. Next, when the capacitor 22 is charged by the battery blocks 11d and 11e by the first execution of the second process P2, the charging voltage of the capacitor 22 becomes higher than the reference voltage VB. Thereafter, by the first execution of the third process P3, the battery block 11a to be measured and the capacitor 22 are connected, and the capacitor 22 is discharged. At this time, a voltage is generated in the capacitor C connected in parallel to the disconnected portion of the conductive member SP. Then, after the second process P2 and the third process are performed for the second time, the voltage of the capacitor 22 after the implementation of the third process P3 is compared with the threshold value Th. At this time, by determining that the voltage of the capacitor 22 is higher than the threshold value Th, it is determined that the conductive member SP in the battery block 11a to be measured has an abnormality.

  When there is an abnormality in the conductive member SP in the battery block 11a to be measured, the control device 30 performs a process such that power supply from the battery pack 10 to the motor (not shown) or the like is not performed. . For example, the system main relay (not shown) for connecting the battery assembly 10 and the motor is turned off.

  According to the above, the following excellent effects can be achieved.

  (1) Since the diode D is connected in parallel to the conductive member SP in the battery block 11, the capacitor 22 is charged with the voltage of the battery block 11 regardless of the presence or absence of abnormality of the conductive member SP in the battery block 11. be able to. In addition, after charging capacitor 22 with a voltage higher than that of battery block 11 to be measured, when connecting battery block 11 to be measured and capacitor 22 to discharge capacitor 22, conductive member SP in battery block 11 If no abnormality occurs, the voltage of the capacitor 22 drops to the voltage of the battery block 11 to be measured. On the other hand, if an abnormality occurs in the conductive member SP in the battery block 11, the voltage of the capacitor 22 is measured in the battery block 11 to be measured by the voltage generated in the noise countermeasure capacitor C connected in parallel to the conductive member SP. It will not drop to the voltage. Thus, the presence or absence of abnormality of the conductive member SP in the battery block 11 to be measured is utilized by utilizing the fact that the voltage of the capacitor 22 is different depending on the presence or absence of the abnormality of the conductive member SP in the battery block 11. In the case of detection, abnormality detection can be performed without adding a new configuration to the battery block 11.

  (2) By acquiring the voltage of the battery block 11 to be measured in advance as the reference voltage VB, the battery block 11 to be measured can be compared by comparing the reference voltage VB with the voltage of the capacitor 22 after the discharge processing. It is possible to accurately determine the presence or absence of an abnormality in the conductive member SP inside.

  (3) If an abnormality occurs in at least one of the conductive members SP in the battery block 11 to be measured, the voltage of the capacitor 22 after the discharge processing becomes higher than the reference voltage VB. Therefore, as the battery block 11 to be measured, the battery block 11 to be measured is connected by performing discharge processing by connecting the battery blocks 11 whose number is smaller than the number of battery blocks 11 connected to the capacitor 22 at the time of charge processing. Abnormality of the conductive member included in 11 can be determined at one time.

  (4) By connecting two or more adjacent battery blocks 11 and the capacitor 22 in parallel, the capacitor 22 can be charged with a voltage larger than the voltage of the battery block 11 to be measured.

  (5) When an abnormality occurs in the conductive member SP in the battery block 11 to be measured, the discharge process is repeatedly performed on the battery block 11 to be measured, whereby the conductive member SP in the abnormal portion is connected in parallel The voltage of the capacitor C gradually rises, and the difference between the reference voltage VB and the charging voltage of the capacitor 22 after the discharging process increases. Therefore, the abnormality determination is performed on the condition that the charging process and the discharging process are repeated more than a predetermined number of times for the battery block 11 to be measured. Thus, the accuracy of the abnormality determination of the conductive member SP in the battery block 11 can be enhanced.

  (6) When the conductive member SP in the battery block 11 is abnormal, when the discharging process after the charging process is performed, a voltage is generated in the capacitor C connected in parallel to the conductive member SP in the abnormal portion. Here, when the battery block 11 to be measured is used as the charging process when the charging process and the discharging process are repeated, the second connection P2 for charging the capacitor 22 is connected in parallel to the conductive member SP at the abnormal point. The charge of the capacitor C is discharged and the voltage is reset to 0V. Therefore, the charging process is not performed using the battery block 11 to be measured. As described above, the accuracy of the abnormality determination of the conductive member SP in the battery block 11 to be measured is set by preventing the voltage accumulated in the capacitor 22 from being reset by repetition of the charging process and the discharging process. It can be enhanced.

  The above embodiment may be modified, for example, as follows. In the following description, the same components as those described above are denoted by the same reference numerals and detailed description thereof will be omitted.

  In the above description, in the flowchart of FIG. 6, the condition is that the charging process (second process P2) and the discharging process (third process P3) of the capacitor 22 have been repeatedly performed a predetermined number of times or more in S15. May be omitted. For example, the abnormality determination of the conductive member SP in the battery block 11 may be performed each time the discharging process after the charging process of the capacitor 22 is performed.

  -In the above, if there is an abnormality in the conductive member SP in the battery block 11, the conductive member SP is repeatedly performed by repeatedly performing the charging process (second process P2) and the discharging process (third process P3) of the capacitor 22. The voltage of the capacitor C connected in parallel to the abnormal point is gradually raised, whereby the determination accuracy of the presence or absence of the abnormality of the conductive member SP in the battery block 11 can be enhanced. Besides this, by increasing the degree of increase in the voltage of the capacitor C paralleled to the abnormal portion of the conductive member SP in the battery block 11 at the time of the charge processing of the capacitor 22, the accuracy of abnormality determination is enhanced. May be For example, when the capacitor 22 is charged, the capacitor 22 and the entire battery block 11 are connected. In this case, if an abnormality occurs in the conductive member SP in the battery block 11 to be measured, the voltage of the capacitor C connected in parallel to the conductive member SP in the abnormal part is largely increased by the discharge process. As described above, by raising the charging voltage of the capacitor 22 during the charging process (second process P2), the voltage of the capacitor C can be increased without repeating the charging process and the discharging process, which causes an abnormality. The accuracy of the determination can be enhanced.

  -Although the threshold value Th is set based on the reference voltage VB acquired by 1st process P1 in the above, abnormality determination may be performed using the predetermined threshold value Th stored beforehand. Further, the threshold Th is set individually for each battery block 11, and the threshold Th common to each battery block 11 may be set in advance.

  In the above, the capacitor 22 is charged in units of the battery block 11 in the second process P2. Besides this, in the case of a configuration in which the capacitor 22 can be charged per battery cell CE, the plurality of batteries can be operated on the condition that the total voltage of the plurality of battery cells CE becomes higher than the reference voltage VB. The cell CE and the capacitor 22 may be connected to perform the second process P2.

  In the above, there is a possibility that an abnormality has occurred in the plurality of conductive members SP provided in the battery block 11. In this case, when the capacitor 22 is discharged in the third process P3, a voltage is generated in each of the capacitors C connected in parallel to the conductive member SP having an abnormality. Accordingly, in the third process P3 After the implementation, the difference between the voltage of the capacitor 22 and the reference voltage VB increases. Therefore, the degree of abnormality of the conductive member SP in the battery block 11 may be determined based on the increase degree of the voltage of the capacitor 22 when the third process P3 is performed. That is, it may be determined that the degree of abnormality of conductive member SP provided in battery block 11 is higher as the difference between the voltage of capacitor 22 and reference voltage VB becomes larger.

  In the example of FIG. 2 described above, the capacitors C are individually connected in parallel to the battery cells CE and the conductive members SP in the battery block 11. Besides this, as shown in the example of FIG. 7, one capacitor C common to all the battery cells CE and all the conductive members SP in the battery block 11 may be connected in parallel. Also in this case, by performing the same process as described above, abnormality determination of the conductive member SP in the battery block 11 to be measured can be performed using the charge voltage of the capacitor 22 after the discharge process. The capacitor C is not limited to the above as long as it is connected to the positive electrode side and the negative electrode side in the circuit of the battery block 11 or the assembled battery 10 across at least one conductive member SP.

  DESCRIPTION OF SYMBOLS 10 ... Battery group, 11 ... Battery block, 22 ... Capacitor, 30 ... Control apparatus, C ... Capacitor | condenser, CE ... Battery cell, D ... Diode, SP ... Conductive member.

Claims (8)

Battery monitoring for monitoring the presence or absence of abnormality in a battery assembly (10) configured by connecting in series a plurality of battery blocks (11) configured by a series connection of a battery cell (CE) and a conductive member (SP) A device,
Capacitors (22) switchably connected in parallel to each of the battery blocks;
A current limiting element (D) connected in parallel to the conductive member so that the current of the battery cell flows in one direction instead of the conductive member when the conductive member is abnormal;
A capacitive component (C) connected in parallel to the conductive member;
A charge processing unit that performs a charging process of charging the capacitor by connecting in parallel a plurality of the battery blocks and the capacitor so that the capacitor is charged with a voltage larger than the voltage of the battery block to be measured 30) and
A discharge processing unit (30) which performs a discharge process of discharging the charge of the capacitor to the battery block to be measured by connecting in parallel the battery block to be measured and the capacitor after the charge processing;
An abnormality determination unit (30) that determines the presence or absence of an abnormality in the conductive member in the battery block to be measured based on the voltage of the capacitor after the discharge processing;
A battery monitoring device comprising: Before performing the charging process, the capacitor is charged with the voltage of the battery block to be measured, and the charging voltage of the capacitor at that time is a reference voltage (VB) which is a reference value of the voltage of the battery block to be measured And a reference voltage acquisition unit (30) to acquire
The battery monitoring device according to claim 1, wherein the abnormality determining unit determines that the battery block to be measured has an abnormality on the condition that a voltage of the capacitor after the discharge processing becomes larger than the reference voltage. .   The selection part (30) which selects the said battery block as many as the number of the said battery blocks connected to the said capacitor in the case of the said charge process as a battery block of the said measurement object is provided. The battery monitoring device according to item 1.   The battery monitoring device according to any one of claims 1 to 3, wherein the charge processing unit performs the charging process by connecting two or more adjacent battery blocks and the capacitor in parallel.   The abnormality determination unit performs abnormality determination on the measurement target battery block on the condition that the charge processing and the discharge processing on the measurement target battery block are repeated more than a predetermined number of times. The battery monitoring apparatus of any one of -4.   The battery monitoring device according to claim 5, wherein the charge processing unit performs the charging process using a battery block other than the battery block to be measured.   The said charge process part connects in parallel all the said battery blocks which comprise the said assembled battery, and the said capacitor, The said capacitor is charged with the voltage of the battery block of any one of Claims 1-4. Battery monitoring device. The battery block is configured to include a plurality of conductive members,
The said abnormality determination part determines the degree of abnormality of the said electrically conductive member in the battery block of the said measurement object based on the rise degree of the voltage of the said capacitor after the said discharge process. The battery monitoring device according to.

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