Monitoring device and power supply system

Abstract

The purpose of the present disclosure is to provide a monitoring device and a power supply system capable of evaluating the validity of a battery.　In order to achieve the above purpose, the present disclosure employs, as the solution, a monitoring device for monitoring a battery provided with a plurality of battery cells electrically connected in series, the monitoring device comprising: a voltage detection unit that is electrically connected to the plurality of battery cells via a predetermined voltage detection line and that detects electrode voltages of the plurality of battery cells; a plurality of discharge circuits that forcibly discharge the plurality of battery cells; and an evaluation unit that calculates, as a path resistance value, a resistance value of the voltage detection line on the basis of the electrode voltages when specific battery cells are forcibly discharged by the plurality of discharge circuits and the electrode voltages when the battery cells are not forcibly discharged, and evaluates the validity of the battery on the basis of the path resistance value.

Description

Monitoring Device and Power Supply System 【0001】 The present disclosure relates to a monitoring device and a power supply system. 【0002】 Patent Document 1 below discloses a vehicle power supply system that can accurately measure the voltage values of each single cell of a battery module in a short time. This vehicle power supply system stores the cell voltage of each of a plurality of battery cells in a self-controller when the battery controller is activated, and after closing the contactor, transmits the stored cell voltages from the self-controller to the upper control device to shorten the activation time of the battery controller. 【0003】 Japanese Patent Application Laid-Open No. 2009-089484 【0004】 By the way, batteries used in vehicles such as hybrid vehicles are made by various manufacturers, and the characteristics of the batteries differ depending on the manufacturer. Therefore, when batteries of different manufacturers are installed in a vehicle, there is a risk of problems such as failure of the battery controller or inability to extract the performance that can originally be extracted from the battery. 【0005】 The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a monitoring device and a power supply system capable of evaluating the legitimacy of a battery. 【0006】 The monitoring device according to the first aspect of the present disclosure is a monitoring device that monitors a battery including a plurality of battery cells electrically connected in series, and is electrically connected to the plurality of battery cells via a predetermined voltage detection line. A voltage detection unit that detects the electrode voltages of the plurality of battery cells, a plurality of discharge circuits that forcibly discharge the plurality of battery cells, and the electrode voltage when a specific one of the plurality of battery cells is forcibly discharged by the plurality of discharge circuits And an evaluation unit that calculates the resistance value of the voltage detection line as a path resistance value based on the electrode voltage when the battery cell is not forcibly discharged, and evaluates the legitimacy of the battery based on the path resistance value. 【0007】A monitoring device according to a second aspect of the present disclosure is a battery monitoring device comprising a plurality of battery cells and electrically connected to a load side via a contactor, comprising: a plurality of input terminals electrically connected to one pole and the other pole of each of the plurality of battery cells via voltage detection lines; a voltage acquisition circuit electrically connected to the plurality of input terminals and acquiring the cell voltage of each of the plurality of battery cells; and a control circuit having a voltage detection unit for detecting the cell voltage acquired by the voltage acquisition circuit, wherein the control circuit has a voltage detection line resistance calculation unit that calculates the resistance value of a specific voltage detection line as identification information for the battery when the voltage detection line is electrically connected to the plurality of input terminals and the monitoring device is started for the first time thereafter. 【0008】 In a third aspect of the present disclosure, the monitoring device, in a second aspect, comprises a voltage detection line resistance calculation unit that calculates the resistance value of the specific voltage detection line before the contactor is closed. 【0009】 A monitoring device according to a fourth aspect of the present disclosure, in a third aspect, further comprises a communication circuit, the control circuit outputting from the communication circuit information relating to the resistance value of the specific voltage detection line calculated by the voltage detection line resistance calculation unit before the contactor is closed. 【0010】 A monitoring device according to a fifth aspect of the present disclosure further comprises, in any of the second to fourth aspects, an electrically series connection circuit of a resistor and a switch provided corresponding to each of the plurality of battery cells and electrically connected between the input terminals to which the corresponding battery cells are electrically connected, wherein the voltage detection line resistance calculation unit calculates the voltage difference in the specific voltage detection line using the voltage detected when the switch corresponding to the battery cell to which the specific voltage detection line is electrically connected is opened and closed according to a predetermined opening and closing pattern, calculates the current flowing through the specific voltage detection line, and calculates the resistance value of the specific voltage detection line from the calculated voltage difference and current. 【0011】A monitoring device according to a sixth aspect of the present disclosure, in a fifth aspect, comprises an integrated circuit comprising at least the voltage acquisition circuit, a part of the series connection circuit, and the control circuit, wherein the predetermined switching pattern is such that the specific voltage detection line is a voltage detection line electrically connected between two potentialally adjacent battery cells in the electrically series connection of the plurality of battery cells, and of the two potentialally adjacent battery cells, the higher potential battery cell corresponds to an odd-numbered battery cell in the electrical series connection order of the plurality of battery cells, and the lower potential battery cell corresponds to an even-numbered battery cell, and the relationship between the number of the plurality of battery cells Nb and the number of channels Nc into which the cell voltage is input to the integrated circuit is Nc = Nb + 1, then the first switching pattern is such that the switch corresponding to the higher potential battery cell is closed and the switch corresponding to the lower potential battery cell is opened. The first pattern is followed by a second pattern in which the switches corresponding to the high-potential battery cell and the low-potential battery cell are opened, the second pattern in which the switches corresponding to the high-potential battery cell and the low-potential battery cell are opened, the third pattern in which the switches corresponding to the low-potential battery cell are closed, and the second pattern in which the switches corresponding to the low-potential battery cell are closed, the third pattern in which the switches corresponding to the low-potential battery cell are opened, and the switches corresponding to the low-potential battery cell are closed, the second pattern in which the switches corresponding to the high-potential battery cell are closed, the second pattern in which the switches corresponding to the high-potential battery cell are opened, and the switches corresponding to the low-potential battery cell are closed, the second pattern in which the switches corresponding to the high-potential battery cell are closed, and the second pattern in which the switches corresponding to the high-potential battery cell are closed, the second pattern in which the switches corresponding to the high-potential battery cell are opened, and the switches corresponding to the low-potential battery cell are closed. 【0012】 A monitoring device according to a seventh aspect of the present disclosure, in any of the second to fourth embodiments, further comprises a voltage detection line abnormality diagnosis unit that detects abnormalities in the specific voltage detection line, the voltage detection line abnormality diagnosis unit compares the resistance value of the specific voltage detection line calculated by the voltage detection line resistance calculation unit with a preset abnormality diagnosis resistance threshold, and determines that there is an abnormality in the voltage detection line if the resistance value of the specific voltage detection line is higher than the abnormality diagnosis resistance threshold. 【0013】 A monitoring device according to an eighth aspect of the present disclosure, in a seventh aspect, further comprises a communication circuit, wherein the control circuit outputs a normal flag from the communication circuit when the voltage detection line abnormality diagnosis unit determines that there is no abnormality in the specific voltage detection line, and outputs an abnormality flag and information that can identify the abnormal voltage detection line from the communication circuit when the voltage detection line abnormality diagnosis unit determines that there is an abnormality in the specific voltage detection line. 【0014】 In the ninth aspect of the present disclosure, in the first aspect, the monitoring device includes an evaluation unit which evaluates the validity of the battery before a contactor provided between the battery and the load is closed. 【0015】 In the monitoring device according to the tenth aspect of the present disclosure, in the first or ninth aspect, the evaluation unit notifies an external party of the evaluation result of the validity of the battery. 【0016】 In the monitoring device of the eleventh aspect of the present disclosure, in the first or ninth aspect, the evaluation unit forces a specific battery cell to discharge, which is a battery cell with an odd or even cell number. 【0017】 A power supply system according to a first aspect of the present disclosure comprises a monitoring device according to a first or ninth aspect and the battery to be monitored. 【0018】 According to this disclosure, it is possible to provide a monitoring device and a power supply system capable of evaluating the validity of a battery. 【0019】This is a block diagram showing the configuration of a monitoring device and a power supply system according to one embodiment of the present disclosure. This is a timing chart showing the operation of the monitoring device according to one embodiment of the present disclosure. This is a first flowchart showing the operation of the monitoring device according to one embodiment of the present disclosure. This is a first schematic diagram showing the operation of the monitoring device according to one embodiment of the present disclosure. This is a second schematic diagram showing the operation of the monitoring device according to one embodiment of the present disclosure. This is a second flowchart showing the operation of the monitoring device according to one embodiment of the present disclosure. This is a block diagram showing the system configuration of a vehicle in a modified example of one embodiment of the present disclosure. This is a first block diagram showing the configuration of a battery management system in a modified example of one embodiment of the present disclosure. This is a second block diagram showing the configuration of a battery management system in a modified example of one embodiment of the present disclosure. This is a third block diagram showing the configuration of a battery management system in a modified example of one embodiment of the present disclosure. This is a timing chart showing the operation of a monitoring device according to a modified example of one embodiment of the present disclosure. 【0020】 Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. As shown in Figure 1, the power supply system in this embodiment comprises a monitoring device A according to this embodiment and a battery B which is the object of monitoring by the monitoring device A. 【0021】 This power supply system provides DC power to the load E via a first contactor C and a second contactor D. Furthermore, this power supply system is an in-vehicle device installed in vehicles such as electric vehicles and hybrid vehicles. 【0022】 To explain battery B first, as shown in the figure, battery B comprises a plurality of battery cells b1 to b60 (60 in total) electrically connected in series. In addition, of the pair of output terminals of battery B, the first contactor C is connected to the lower potential output terminal (negative terminal), and the second contactor D is connected to the higher potential output terminal (positive terminal). 【0023】In other words, battery B has its negative terminal connected to one end of the first contactor C and its positive terminal connected to one end of the second contactor D. This battery B supplies DC power (battery power) to the load E via the first contactor C and the second contactor D. 【0024】 The first contactor C is a switch located between battery B and load E on the negative terminal side of battery B. One contact is connected to the negative terminal of battery B, and the other contact is connected to one input terminal of load E. The first contactor C switches between connecting and disconnecting the negative terminal of battery B and one input terminal of load E by controlling the conduction / disconnection of the pair of contacts by monitoring device A. 【0025】 The second contactor D is a switch located between battery B and load E on the positive terminal side of battery B. One contact is connected to the positive terminal of battery B, and the other contact is connected to the other input terminal of load E. The second contactor D switches between connecting and disconnecting the positive terminal of battery B and the other input terminal of load E by controlling the conduction / disconnection of the pair of contacts by monitoring device A. 【0026】 Load E is, for example, an inverter and a motor. Load E generates power based on battery power input from battery B via first and second contactors 1 and 2. That is, Load E generates power by converting battery power into AC power using an inverter and supplying this AC power to the motor. 【0027】 Furthermore, as shown in the figure, battery B is electrically connected to monitoring device A by multiple (61 in total) voltage detection lines L1 to L61. The 61 voltage detection lines L1 to L61 connect the negative and positive electrodes of a total of 60 battery cells b1 to b60 to a total of 61 input terminals T1 to T61 provided on monitoring device A. These voltage detection lines L1 to L61 are dedicated wires specifically for battery B. 【0028】Here, the specifications of the voltage detection lines L1 to L61 differ depending on the manufacturer of battery B. In other words, the individual DC resistance values ​​of the 61 voltage detection lines L1 to L61 differ depending on the manufacturer of battery B. Therefore, if the vehicle is mistakenly fitted with a battery from another manufacturer (the wrong battery) instead of the battery B from the manufacturer it should be fitted with, the DC resistance values ​​of the voltage detection lines L1 to L61 will be different from the original resistance values. 【0029】 As will be described in more detail later, the DC resistance values ​​of voltage detection lines L1 to L61 can be calculated based on the voltages applied to voltage detection lines L1 to L61 from battery cells b1 to b60. In this embodiment, the monitoring device A detects the cell voltages of multiple battery cells and calculates the DC resistance values ​​of voltage detection lines L1 to L61 as the path resistance value K based on these cell voltages. 【0030】 As shown in the figure, monitoring device A includes a total of 61 input terminals T1 to T61 corresponding to a total of 61 voltage detection lines L1 to L61, a total of 61 discharge resistors R1 to R61 corresponding to a total of 61 input terminals T1 to T61, a voltage detection unit F, and a control unit G. 【0031】 The 61 input terminals T1 to T61 are each connected to the other end of the 61 voltage detection lines L1 to L61, as shown in the figure. For example, the first input terminal T1 is connected to the other end of the first voltage detection line L1, and the second input terminal T2 is connected to the other end of the second voltage detection line L2. (omitted) Also, the 61st input terminal T61 is connected to the other end of the 61st voltage detection line L61. 【0032】 The 61 discharge resistors R1, R2, ..., R61 all have the same resistance value (discharge resistance value H), and one end of each is connected to the corresponding input terminal T1 to T61. For example, the first discharge resistor R1 has one end connected to the second input terminal T2, and the second discharge resistor R2 has one end connected to the third input terminal T3. (omitted) Furthermore, the 61st discharge resistor R61 has one end connected to the 61st input terminal T61. 【0033】Furthermore, the other end of each of the 61 discharge resistors R1 to R61 is connected to the discharge input terminal of the voltage detection unit F corresponding to itself. For example, the other end of the first discharge resistor R1 is connected to the first discharge input terminal of the voltage detection unit F, and the other end of the second discharge resistor R2 is connected to the second discharge input terminal of the voltage detection unit F. (omitted) In addition, the other end of the 61st discharge resistor R61 is connected to the 61st discharge input terminal of the voltage detection unit F. 【0034】 The voltage detection unit F has at least a total number of input terminals (1st to 61st input terminals and 1st to 61st discharge input terminals) corresponding to the number of voltage detection lines L1 to L61 and the number of discharge resistors R1 to R61. This voltage detection unit F is connected to the electrodes of each battery cell b1 to b60 via the 1st to 61st input terminals and each voltage detection line L1 to L61, and is also connected to the other ends of each discharge resistor R1 to R61 via the 1st to 61st discharge input terminals. 【0035】 For example, the voltage detection unit F has a first input terminal connected to the negative electrode of the first battery cell b1 via a first voltage detection line L1. The voltage detection unit F also has a second input terminal connected to the positive electrode of the first battery cell b1 and the negative electrode of the second battery cell b2 via a second voltage detection line L2. (omitted) Furthermore, the voltage detection unit F has a 61st input terminal connected to the positive electrode of the 60th battery cell b60 via a 61st voltage detection line L61. 【0036】 Furthermore, the voltage detection unit F has its first discharge input terminal connected to the other end of the first discharge resistor R1, and the voltage detection unit F has its second discharge input terminal connected to the other end of the second discharge resistor R2. (omitted) In addition, the voltage detection unit F has its 61st discharge input terminal connected to the other end of the 61st discharge resistor R61. 【0037】 The voltage detection unit F comprises at least a multiplexer that selects the electrode voltages of each battery cell b1 to b60 input to the first to 61st input terminals, and an A / D converter that converts the output (analog signal) of the multiplexer into a digital signal, and sequentially detects the electrode voltages of each battery cell b1 to b60 as cell voltages in a time series. 【0038】Furthermore, this voltage detection unit F is equipped with a total of 60 discharge switches (on / off switches) connected to the first to 61st discharge input terminals. Each discharge switch is connected in series with each discharge resistor R1 to R61, and when set to the closed state (ON state), each discharge resistor R1 to R61 is connected in parallel with each battery cell b1 to b60. 【0039】 For example, the first discharge switch is connected in series with the first discharge resistor R1 and the second discharge resistor R2, and when set to the closed state (ON state), it connects the first discharge resistor R1 and the second discharge resistor R2 in parallel with the first battery cell b1. In other words, when the first discharge switch is set to the closed state (ON state), it forces the first battery cell b1 to discharge via the first discharge resistor R1 and the second discharge resistor R2. 【0040】 The second discharge switch is connected in series with the second discharge resistor R2 and the third discharge resistor R3. When set to the closed state (ON state), it connects the second discharge resistor R2 and the third discharge resistor R3 in parallel with the second battery cell b2. In other words, when the second discharge switch is set to the closed state (ON state), it forces the second battery cell b2 to discharge via the second discharge resistor R2 and the third discharge resistor R3. 【0041】 (omitted) The 60th discharge switch is connected in series with the 60th discharge resistor R60 and the 61st discharge resistor R61, and when set to the closed state (ON state), it connects the 60th discharge resistor R60 and the 61st discharge resistor R61 in parallel with the 60th battery cell b60. In other words, when the 60th discharge switch is set to the closed state (ON state), it forces the 60th battery cell b60 to discharge via the 60th discharge resistor R60 and the 61st discharge resistor R61. 【0042】 These discharge resistors R1 to R61 and each discharge switch constitute a plurality of discharge circuits that equalize the charge state of each battery cell b1 to b60. In other words, each discharge switch is a cell balance switch (BALSW) for equalizing the charge state of each battery cell b1 to b60. 【0043】 That is, the first discharge resistor R1, the second discharge resistor R2, and the first discharge switch constitute a first discharge circuit that is connected in parallel to the first battery cell b1. Also, the second discharge resistor R2, the third discharge resistor R3, and the second discharge switch constitute a second discharge circuit that is connected in parallel to the second battery cell b2. (Omitted) The 60th discharge resistor R60, the 61st discharge resistor R61, and the 60th discharge switch constitute a 60th discharge circuit that is connected in parallel to the 60th battery cell b60. 【0044】 The voltage detection unit F detects the electrode voltages of the battery cells b1 to b60 input to the first to 61st input terminals, and sequentially outputs the electrode voltages of the battery cells b1 to b60 to the control unit G. Such a voltage detection unit F corresponds to the voltage detection unit in the present disclosure. 【0045】 Also, the voltage detection unit F equalizes (balances) the charge states of the battery cells b1 to b60 by setting each discharge switch (BALS W) to ON / OFF based on the switch control signal input from the control unit G. 【0046】 The control unit G is a microcomputer that exhibits a predetermined control function by executing a control program stored in advance. This control unit G has a communication function for transmitting and receiving signals to and from a host control device, and controls the power supply to the load E of the battery power by opening and closing the first and second contactors 1 and 2 based on a control command input from the host control device. 【0047】 Also, this control unit G generates a switch control signal for setting each discharge switch (BALS W) of the voltage detection unit F to ON / OFF based on the electrode voltages of the battery cells b1 to b60, and outputs it to the voltage detection unit F. That is, the control unit G performs cell balance processing of the battery cells b1 to b60 based on the electrode voltages of the battery cells b1 to b60. 【0048】Further, although details will be described later, the control unit G performs the validity evaluation process of the battery B based on the electrode voltages of the battery cells b1 to b60 when each battery cell b1 to b60 is forcibly discharged in a specific pattern by controlling each discharge switch (BALS W). Such a control unit G corresponds to the evaluation unit in the present disclosure. 【0049】 Next, the operations of the monitoring device A (voltage detection device) and the power supply system according to the present embodiment will be described with reference to FIGS. 2 to 5. 【0050】 First, referring to the timing chart shown in FIG. 2, the processing timing of the validity evaluation process of the battery B performed by the control unit G of the monitoring device A will be described. As shown in FIG. 2, the control unit G acquires (AD latch) the electrode voltages of the battery cells b1 to b60 when a specific battery cell among the battery cells b1 to b60 is forcibly discharged within 200 ms immediately after the first startup. 【0051】 That is, the control unit G evaluates the validity of the battery B within 200 ms, which is the period until the first contact C and the second contact D provided between the battery B and the load E are turned on immediately after the first startup. 【0052】 Then, the control unit G acquires the path resistance value K of each battery cell b1 to b60 based on the above electrode voltage, and based on this path resistance value K, checks the validity of the battery B, that is, whether a regular battery is mounted on the vehicle or whether an incorrect battery of a manufacturer different from that of the regular battery is mounted. 【0053】 Here, the above-described battery B is an in-vehicle battery having a total of 60 battery cells b1 to b60, that is, a cell number of 60, but there are in-vehicle batteries having 48 or 72 cells. FIG. 2 shows that the discharge patterns of the plurality of battery cells b when acquiring the path resistance value K vary according to the cell number. 【0054】In Figure 2, when there are 60 cells, during the first 100ms (20ms x 5) period, the discharge switches (BALSW) connected in parallel to the even-numbered battery cells b2, b4, ..., b60 are set to the ON state (closed state), thereby forcing the discharge of the even-numbered battery cells. In other words, in battery B with 60 cells, the specific battery cells are the even-numbered battery cells b2, b4, ..., b60. 【0055】 In contrast, in the case of 72-cell and 48-cell batteries, by setting the discharge switch (BALSW) connected in parallel to the odd-numbered battery cells to the ON state (closed state), the odd-numbered battery cells are forcibly discharged for the first 100ms (20ms x 5) period, and then again for the next 40ms (20ms x 2) period. 【0056】 Then, during the next 400ms (20ms x 2) period, the discharge switch (BALSW) connected in parallel to the odd-numbered battery cells is set to the ON state (closed state), thereby forcing the discharge of the odd-numbered battery cells. In other words, in batteries with 72 and 48 cells, the specific battery cells are those with odd-numbered cell numbers. 【0057】 Next, the procedure for evaluating the validity of battery B will be explained with reference to the flowchart in Figure 3 and the schematic diagrams in Figures 4 and 5. Note that Figures 4 and 5 are excerpts from Figure 1 showing the circuit portions related to the fourth battery cell b4 and the fifth battery cell b5, corresponding to cell numbers "4" and "5," respectively, for the sake of clarity. 【0058】 In this validation process, the control unit G first acquires the discharge voltage (step S1). That is, the control unit G acquires the electrode voltage of each battery cell b1 to b60 when each battery cell b1 to b60 is forcibly discharged according to the discharge pattern. 【0059】Since battery B is an on-board battery with 60 cells, the control unit G acquires the electrode voltage of each battery cell b1 to b60 while forcibly discharging each battery cell b2, b4, ..., b60, which corresponds to an even cell number. 【0060】 Referring to Figure 4, the discharge voltage acquisition process in step S1 will be explained as follows: The control unit G sets the fourth discharge switch SW4, which is connected in parallel to the fourth battery cell b4 whose cell number is even, to the ON state (closed state), and leaves the fifth discharge switch SW5, which is connected in parallel to the fifth battery cell b5 whose cell number is odd, in the OFF state (open state). 【0061】 As a result, the fourth path current I4 flows from the positive electrode of the fourth battery cell b4 → the fifth voltage detection line L5 → the fifth input terminal T5 → the fourth discharge resistor R4 → the fourth discharge switch SW4 → the third discharge resistor R3 → the fourth input terminal T4 → the fourth voltage detection line L4 → to the negative electrode of the fourth battery cell b4. 【0062】 The fourth path current I4 can be calculated based on the electrode voltages V5 and V4 of the fourth battery cell b4, since the discharge resistance values ​​H of the third discharge resistor R3 and the fourth discharge resistor R4 are known. Specifically, the control unit G calculates the fourth path current I4 by dividing the differential voltage ΔV45 of the electrode voltages V5 and V4 obtained from the voltage detection unit F by the discharge resistance value H that is stored in advance. 【0063】 On the other hand, for the fifth battery cell b5, since the fifth discharge switch SW5 is set to the OFF state (open state), the fifth path current I5 is extremely small compared to the fourth path current I4. 【0064】 The control unit G obtains the fourth electrode voltage V4_on, the fifth electrode voltage V5_on, and the sixth electrode voltage V6_on for the fourth battery cell b4 and the fifth battery cell b5 from the voltage detection unit F when the fourth discharge switch SW4 is in the ON state (closed state) and the fifth discharge switch SW5 is in the OFF state (open state). 【0065】The control unit G then acquires the non-discharge voltage (step S2). That is, the control unit G acquires the electrode voltage of each battery cell b1 to b60 when each battery cell b1 to b60 is not forcibly discharged. 【0066】 Referring to Figure 5, the non-discharge voltage acquisition process in step S2 is explained as follows: The control unit G keeps both the fourth discharge switch SW4 and the fifth discharge switch SW5 in the OFF state (open state). In this case, the fourth path current I4 and the fifth path current I5 are extremely small compared to the fourth path current I4 in step S1. 【0067】 The control unit G obtains the fourth electrode voltage V4_off, the fifth electrode voltage V5_off, and the sixth electrode voltage V6_off for the fourth battery cell b4 and the fifth battery cell b5 from the voltage detection unit F when both the fourth discharge switch SW4 and the fifth discharge switch SW5 are in the OFF state (open state). 【0068】 Now, focusing on the fifth voltage detection line L5, the difference voltage ΔV4 between the fifth electrode voltage V5_on and the fifth electrode voltage V5_off depends on the path resistance K5 of the fifth voltage detection line L5. That is, the path resistance K5 is obtained by dividing the difference voltage ΔV4 by the fourth path current I4. 【0069】 The control unit G calculates the path resistance value K5 by dividing the differential voltage ΔV4 obtained in steps S1 and S2 by the fourth path current I4 (step S3). Then, the control unit G determines whether this path resistance value K5 falls within a predetermined evaluation range defined by an upper limit value KU and a lower limit value KL (step S4). 【0070】 If the determination in step S4 is "Yes", the control unit G notifies the higher-level control unit that battery B is a genuine battery (step S5). On the other hand, if the determination in step S4 is "No", the control unit G notifies the higher-level control unit that battery B is an incorrect battery (step S6). 【0071】In other words, the control unit G notifies an external higher-level control unit of the evaluation result of the validity of battery B. Then, once the processes in steps S1 to S6 described above are completed, the control unit G terminates the validity evaluation process of battery B. 【0072】 Here, in addition to the validation process for battery B shown in Figure 3, the control unit G performs the detection process for abnormal voltage detection lines (abnormal detection lines) shown in Figure 6. The control unit G obtains the path resistance value K5 of the fifth voltage detection line L5 through the processes in steps S1 to S3 described above, but it is also possible to obtain the path resistance values ​​K1 to K4 and K6 to K61 other than the fifth voltage detection line L5 through the series of processes in steps S1 to S3 (path resistance detection process). 【0073】 As shown in Figure 6, the control unit G obtains the path resistance values ​​K1 to K61 of all voltage detection lines L1 to L61 through the path resistance detection process in steps S1 to S3, and then determines whether each path resistance value K1 to K61 exceeds a predetermined threshold Kr that is stored in advance (step S4a). 【0074】 If the determination in step S4a is "Yes", the control unit G notifies the higher-level control unit of the calculation abnormality of the path resistance values ​​K1 to K61 (step S5a). Then, the control unit G detects an abnormal line by comparing the path resistance values ​​K1 to K61 of all voltage detection lines L1 to L61 with the normal range that is stored in advance (step S6). 【0075】 Then, the control unit G notifies the higher-level control unit of an abnormality flag indicating an abnormality in the calculation of path resistance values ​​K1 to K61 and an abnormality detection line (step S7a). On the other hand, if the determination in step S4a is "No", the control unit G notifies the higher-level control unit of a normal flag indicating that the calculation of path resistance values ​​K1 to K61 is normal and the path resistance values ​​K1 to K61 of all voltage detection lines L1 to L61 (step S8a). 【0076】The monitoring device A according to this embodiment monitors a battery B comprising a plurality of battery cells b1 to b60 electrically connected in series, and includes a voltage detection unit F electrically connected to the plurality of battery cells b1 to b60 via predetermined voltage detection lines L1 to L61 for detecting the electrode voltages of the plurality of battery cells b1 to b60, and a control unit G (evaluation unit) that evaluates the validity of the battery B by calculating the resistance values ​​of the voltage detection lines L1 to L61 as path resistance values ​​based on the electrode voltages. 【0077】 According to this embodiment, the monitoring device A is provided that includes a voltage detection unit F for detecting the electrode voltages of each battery cell b1 to b60, and a control unit G (evaluation unit) for evaluating the validity of the battery B by calculating the path resistance values ​​of the voltage detection lines L1 to L61 based on the electrode voltages. 【0078】 Furthermore, in the monitoring device A according to this embodiment, the monitoring device for battery B is equipped with a plurality of battery cells and electrically connected to the load side via a contactor, and comprises a plurality of input terminals electrically connected to one pole and the other pole of each of the plurality of battery cells via voltage detection lines, a voltage acquisition circuit electrically connected to the plurality of input terminals and acquiring the cell voltage of each of the plurality of battery cells, and a control circuit having a voltage detection unit that detects the cell voltage acquired by the voltage acquisition circuit, wherein the control circuit has a voltage detection line resistance calculation unit that calculates the resistance value of a specific voltage detection line as battery identification information when the voltage detection line is electrically connected to the plurality of input terminals and the monitoring device is started for the first time thereafter. According to this embodiment, when the monitoring device is started for the first time, a specific voltage detection line resistance value is calculated as battery identification information, so it is possible to identify battery B. 【0079】 Furthermore, in the monitoring device A according to this embodiment, the voltage detection line resistance calculation unit calculates the resistance value of a specific voltage detection line before the contactor is turned on, making it possible to identify the battery B. 【0080】Furthermore, in the monitoring device A according to this embodiment, a communication circuit is also provided, and the control circuit outputs information regarding the resistance value of a specific voltage detection line calculated by the voltage detection line resistance calculation unit from the communication circuit before the contactor is closed, thereby improving safety. 【0081】 Furthermore, in the monitoring device A according to this embodiment, a communication circuit is also provided, and the control circuit outputs information regarding the resistance value of a specific voltage detection line calculated by the voltage detection line resistance calculation unit from the communication circuit before the contactor is turned on, so that the battery B can be identified. 【0082】 Furthermore, in the monitoring device A according to this embodiment, there is an electrically series connection circuit of a resistor and a switch provided corresponding to each of the plurality of battery cells and electrically connected between the input terminals to which the corresponding battery cells are electrically connected. The voltage detection line resistance calculation unit calculates the voltage difference in a specific voltage detection line using the voltage detected when the switch corresponding to the battery cell to which a specific voltage detection line is electrically connected is opened and closed according to a predetermined opening and closing pattern, and also calculates the current flowing through the specific voltage detection line, and calculates the resistance value of the specific voltage detection line from the calculated voltage difference and current. According to this embodiment, it is possible to identify battery B. 【0083】Furthermore, in the monitoring device A according to this embodiment, at least the voltage acquisition circuit, a part of the series connection circuit, and the control circuit are composed of an integrated circuit, and the predetermined switching pattern is such that a specific voltage detection line is a voltage detection line electrically connected between two battery cells that are electrically adjacent in potentiality among the electrical series connection of a plurality of battery cells, and among the two battery cells that are electrically adjacent, the higher potential battery cell corresponds to the odd-numbered battery cell in the electrical series connection order of the plurality of battery cells, and the lower potential battery cell corresponds to the even-numbered battery cell, and when the relationship between the number of battery cells Nb and the number of channels Nc into which the cell voltage of the integrated circuit is input is Nc = Nb + 1, the first pattern closes the switch corresponding to the higher potential battery cell and opens the switch corresponding to the lower potential battery cell. In the first case, the switch corresponding to the high-potential battery cell and the switch corresponding to the low-potential battery cell are opened in the second pattern. In the second case, the switch corresponding to the high-potential battery cell is opened and the switch corresponding to the low-potential battery cell is closed. In the third case, the switch corresponding to the high-potential battery cell is opened and the switch corresponding to the low-potential battery cell is closed. In this embodiment, it is possible to identify battery B. 【0084】 Furthermore, in the monitoring device A according to this embodiment, the control circuit further includes a voltage detection line abnormality diagnosis unit that detects abnormalities in a specific voltage detection line. The voltage detection line abnormality diagnosis unit compares the resistance value of the specific voltage detection line calculated by the voltage detection line resistance calculation unit with a preset abnormality diagnosis resistance threshold. If the resistance value of the specific voltage detection line is higher than the abnormality diagnosis resistance threshold, it determines that there is an abnormality in the voltage detection line. This embodiment makes it possible to improve safety. 【0085】Furthermore, in the monitoring device A according to this embodiment, a communication circuit is also provided. The control circuit outputs a normal flag from the communication circuit when the voltage detection line abnormality diagnosis unit determines that there is no abnormality in the specific voltage detection line, and outputs an abnormality flag and information that identifies the abnormal voltage detection line from the communication circuit when the voltage detection line abnormality diagnosis unit determines that there is an abnormality in the specific voltage detection line. This embodiment makes it possible to improve safety. 【0086】 Furthermore, in the monitoring device A according to this embodiment, the evaluation unit evaluates the validity of battery B before the contactor installed between battery B and the load is closed, so it is possible to determine the erroneous battery before supplying DC power from battery B to the load. 【0087】 Furthermore, in the monitoring device A according to this embodiment, the evaluation unit notifies an external party of the evaluation result of the validity of battery B, enabling a quick response to incorrect battery use. 【0088】 Furthermore, in the monitoring device A according to this embodiment, the evaluation unit forcibly discharges battery cells with odd or even cell numbers as specific battery cells, making it possible to accurately evaluate the validity of various batteries B. 【0089】 Furthermore, the power supply system according to this embodiment includes a monitoring device and a battery B that is the object of monitoring. According to this embodiment, it is possible to provide a power supply system that can evaluate the legitimacy of the battery B. 【0090】 This disclosure is not limited to the embodiments described above, and the following modifications are possible for the vehicle's system configuration, battery device, and especially the configuration of the battery management system (BMS). 【0091】First, using Figure 7, we will explain a modified example of the vehicle's system configuration, that is, the configuration of the drive system of a hybrid electric vehicle (hereinafter referred to as "HEV") 1 including the battery unit 100. Figure 7 shows the configuration of the drive system of the HEV 1 and the electrical connection configuration of each component of the electric drive unit that constitutes a part thereof. Here, thick solid lines indicate the high-voltage system, and thin solid lines with arrows indicate the low-voltage system. 【0092】 HEV1 is equipped with a parallel hybrid drive system. The parallel hybrid drive system arranges the engine 4, which is an internal combustion engine, and the motor generator 200 in parallel relative to the drive wheels 2 in terms of energy flow (structurally, the engine 4 and the motor generator 200 are mechanically connected in series via a clutch 5, which is a power transmission control mechanism), and is configured to drive the drive wheels 2 using the rotational power of the engine 4, the rotational power of the motor generator 200, and the rotational power of both the engine 4 and the motor generator 200. In other words, the parallel hybrid drive system comprises an engine drive unit that uses the engine 4 as a power source and is mainly used as the drive source for HEV1, and an electric drive unit that uses the motor generator 200 as a power source and is mainly used as the drive source for HEV1 and as a power generation source for HEV1. 【0093】 One type of hybrid system is the series hybrid system, in which the energy flow from the engine to the drive wheels is in a series, using the rotational power of an internal combustion engine to drive a generator, the electricity generated by this drive to drive a motor generator, and the rotational power generated by this drive to drive the drive wheels. Another type of hybrid system is the series-parallel hybrid system, which combines the above-mentioned parallel hybrid system and series hybrid system (a system in which the engine and two motor generators are mechanically connected using a power transmission mechanism such as a planetary gear mechanism so that a portion of the engine's rotational power is distributed to a power-generating motor generator to generate electricity, and the resulting electricity drives the drive motor generator). 【0094】In this embodiment, a parallel hybrid drive system will be used as an example for explanation, but the battery device 100 of this embodiment, described below, may also be applied to the battery devices of other hybrid drive systems mentioned above. Furthermore, the battery device 100 of this embodiment may also be applied to a battery electric vehicle (BEV) that does not have an engine and propels the vehicle solely with power generated by a motor generator based on electricity supplied from the battery device. 【0095】 Furthermore, the battery device 100 of this embodiment adds a function to the HEV1 that allows the battery device to be charged from an external source, and although the main power source is the motor generator driven by electricity supplied from the battery device, it may also be applied to a plug-in hybrid electric vehicle (PHEV) that can propel the vehicle with either hybrid power from the engine and motor generator or power from the engine alone. Moreover, it may also be applied to a fuel cell electric vehicle (FCEV) that propels the vehicle using power from a motor generator driven by electricity generated by a fuel cell as the power source. 【0096】 《Drive System Configuration》 An axle 3 is rotatably supported on the front or rear of the vehicle body (not shown). A pair of drive wheels 2 are provided at both ends of the axle 3. Although not shown, an axle with a pair of driven wheels at both ends is rotatably supported on the rear or front of the vehicle body (not shown). In the HEV1, a front-wheel drive system is adopted, with the drive wheels 2 as the front wheels and the driven wheels as the rear wheels. A rear-wheel drive system or a four-wheel drive system (a system in which one of the front or rear wheels is driven by an engine drive unit and the other is driven by an electric drive unit) may also be adopted as the drive system. 【0097】A differential gear (hereinafter referred to as "DEF") 7 is provided in the center of the axle 3. The axle 3 is mechanically connected to the output side of DEF 7. The output shaft of the transmission 6 is mechanically connected to the input side of DEF 7. DEF 7 is a differential power distribution mechanism that distributes the rotational driving force transmitted by the transmission 6 to the left and right axles 3. The output side of the motor generator 200 is mechanically connected to the input side of the transmission 6. The output side of the engine 4 is mechanically connected to the input side of the motor generator 200 via a clutch 5, which is a power transmission control mechanism. The clutch 5 is controlled to be engaged when the rotational power of the engine 4 is transmitted to the drive wheels 2, and disengaged when the rotational power of the engine 4 is not transmitted to the drive wheels 2. The motor generator 200 and the clutch 5 are housed inside the casing of the transmission 6. 【0098】 《Motor Generator Configuration》 The motor generator 200 is a rotating electric machine that is not shown in the diagram as it is a well-known conventional design, and has an armature (stator in this embodiment) equipped with armature windings and a field (rotor in this embodiment) equipped with permanent magnets, which is positioned opposite the armature with an air gap in between. It functions as a motor when the HEV1 is being driven, and as a generator when the HEV1 is regenerating or when power generation is required. 【0099】 In this embodiment, the motor generator 200 is described using a three-phase AC synchronous machine (permanent magnet field type) as an example, but other three-phase AC synchronous machines (wound field type) or three-phase AC induction machines (using a field with short-circuited conductor bars attached to the field core) may also be used. 【0100】《Motor Generator Operation》 When the motor generator 200 functions as a motor, that is, when the HEV 1 is being powered or when the engine 4 is being started, or when rotational power is required, the electrical energy stored in the battery device 100 is supplied to the armature winding via the inverter device 300. As a result, the motor generator 200 generates rotational power (mechanical energy) through the magnetic action between the armature and the field, and outputs this rotational power. The rotational power output from the motor generator 200 is transmitted to the axle 3 via the transmission 6 and DEF 7 when the HEV 1 is being powered, driving the drive wheels 2, and is transmitted to the engine 4 via the clutch 5 when the engine 4 is being started, driving the engine 4. 【0101】 When the motor generator 200 functions as a generator, that is, when the vehicle is in an operating mode where power generation is required, such as during regenerative braking or deceleration of the HEV 1, or when the battery device 100 needs to be charged while the HEV 1 is running, mechanical energy (rotational power) transmitted from the drive wheels 2 or engine 4 is transmitted to the motor generator 200, and the motor generator 200 is driven. When the motor generator 200 is driven in this way, a voltage is induced in the armature winding due to the magnetic effect between the armature and the field. As a result, the motor generator 200 generates electricity and outputs that electricity. The electricity output from the motor generator 200 is supplied to the battery device 100 via the inverter device 300. As a result, the battery device 100 is charged. 【0102】(4) <Configuration of the Inverter Device> The motor generator 200 is driven by the power between the armature and the battery device 100 being controlled by the inverter device 300. In other words, the inverter device 300 is a control device for the motor generator 200. The inverter device 300 is a well-known type and is therefore not shown in the diagram, but it is equipped with a power module on which multiple power semiconductor elements (also known as switching elements), which are insulated-gate bipolar transistors (IGBTs), and multiple rectifier elements, which are diodes. Metal-oxide-semiconductor field-effect transistors (MOSFETs) may be used as power semiconductor elements. When MOSFETs are used as power semiconductor elements, there is a parasitic diode between the drain electrode and the source electrode, so it is not necessary to electrically connect a diode between them separately. 【0103】 The power module is a power conversion circuit that converts DC power to three-phase AC power during vehicle acceleration and converts three-phase AC power to DC power during vehicle regeneration through the switching operation of multiple power semiconductor elements. The power conversion circuit is configured by electrically connecting three arms, each consisting of two power semiconductor elements electrically connected in series, in parallel, and outputting AC power for each phase from between the power semiconductor elements of each arm. Diodes are electrically connected between the drain electrode and source electrode of each power semiconductor element. 【0104】 Each power semiconductor element switches on and off in response to a corresponding drive signal (gate signal). Each drive signal is generated in the drive circuit based on a corresponding switching command signal (e.g., a PWM (pulse width modulation) signal). Each switching command signal is generated in the motor control unit based on a torque command signal output from the vehicle control unit 8, which controls the entire motor vehicle. 【0105】《Functional Configuration of the Vehicle Control Device》 The vehicle control device 8 generates a motor torque command signal for the motor control device and an engine torque command signal for the engine control device (not shown) based on multiple state parameters indicating the operating state of the vehicle, such as torque requests from the driver and vehicle speed, and outputs the torque command signals to the corresponding control devices. The engine control device is an electronic device that controls the drive of components of the engine 4, such as the air throttle valve, fuel injection valve, and intake / exhaust valve. Based on the engine torque command signal obtained from the output signal of the vehicle control device 8, it generates drive command signals for each component and outputs each drive command signal to the drive circuit of each component. 【0106】 《Outline Configuration of the Battery Device》 The battery device 100 is a high-voltage energy storage device with a nominal output voltage of 200 volts or more, and high output density and energy density, which constitutes the power supply for driving the motor generator 200, and is electrically connected to the inverter device 300 via a junction box 400. 【0107】 《Connection to Low-Voltage Battery Device》 Although not shown in the diagram, a battery device with a lower voltage than the battery device 100 is electrically connected to the battery device 100. The low-voltage battery device is a low-voltage lead-acid battery with a nominal output voltage of 12 volts, which is the power source for in-vehicle auxiliary equipment such as lights and audio systems and electronic control devices, and is electrically connected to the battery device 100 via a DC-DC converter (not shown in the diagram). The DC-DC converter is a power conversion device that converts DC power into DC power that has been stepped up or stepped down to a predetermined voltage. 【0108】Next, we will describe modified configurations of the battery device, particularly the battery management system (BMS), using Figures 8 to 10. <Detailed Configuration of the Battery Device> Figure 8 shows the overall configuration of the battery device 100, and the system configuration including the load (vehicle electric drive system) electrically connected to the battery device 100. Figure 9 shows the electrical connection configuration between one battery cell group (hereinafter referred to as "BCG") 111 of the battery module (hereinafter referred to as "BM") 110 and one cell monitoring integrated circuit (hereinafter referred to as "CMIC") 131 mounted on the cell monitoring unit (hereinafter referred to as "CMU") 130, and the circuit configuration of the CMIC 131. Figure 10 shows the circuit configuration of the microcontroller (hereinafter referred to as "MCU") 141 mounted on the battery monitoring unit (hereinafter referred to as "BMU") 140. 【0109】 The battery unit 100 is an energy storage device that is charged and discharged by the inverter unit 300, and its main components include a BM 110 and a battery management device (hereinafter referred to as "BMS") 120. The BM 110 and BMS 120 are housed together with other devices such as a cooling device (for example, a cooling fan that blows air onto the BM if cooling air is used as the cooling medium) and electrical components such as a junction box 400, in a single power supply enclosure, and are installed under the seats in the passenger compartment, in the trunk, or under the floor. 【0110】 The junction box 400 houses several relays with mechanical contacts. These relays include a positive-side relay 410, a negative-side relay 420, and a pre-charge relay 430. The positive-side relay 410 is a switch for controlling the electrical connection between the DC positive side of the inverter device 300 (power module) and the positive side of the battery device 100 (BM110). The negative-side relay 420 is a switch for controlling the electrical connection between the DC negative side of the inverter device 300 (power module) and the negative side of the battery device 100 (BM110). 【0111】The pre-charge relay 430 is provided in the power path between the DC positive terminal side of the inverter device 300 (power module) and the positive terminal side of the battery device 100 (BM110) to bypass the positive terminal relay 410, in order to prevent the relay contacts from welding due to a large inrush current when the relay is switched on. It is electrically connected in parallel with the positive terminal relay 410. Although not shown in the diagram, a resistor is provided in the pre-charge circuit that bypasses the positive terminal relay 410, electrically connected in series with the pre-charge relay 430. 【0112】 The positive-side relay 410 and the negative-side relay 420 are switched on when the motor-generator 200 is in an operating mode that requires rotational power, or when the motor-generator 200 is in an operating mode that requires power generation. They are switched off when the vehicle is in a stopped mode (when the ignition key switch is open) or when an abnormality occurs in the electric drive system or the vehicle. When the relays are switched on, the contacts of the negative-side relay 420 are closed first, then the contacts of the pre-charge relay 430 are closed, and after a certain amount of power has been supplied to the inverter device 300 and the smoothing capacitor of the inverter device 300 has been charged, the contacts of the positive-side relay 410 are closed. After the contacts of the positive-side relay 410 are closed, the contacts of the pre-charge relay 430 are opened. 【0113】 The opening and closing of the contacts of the positive-side relay 410, the negative-side relay 420, and the pre-charge relay 430 are controlled by opening and closing command signals output from the vehicle control device 8. The opening and closing of the contacts of the positive-side relay 410, the negative-side relay 420, and the pre-charge relay 430 may also be controlled by opening and closing command signals output from other control devices, such as the motor control device of the inverter device 300 or the BMS 120 of the battery device 100. 【0114】《Battery Module Configuration》 The BM110 is capable of storing and releasing electrical energy electrochemically and is electrically connected to the inverter device 300 (power module) via a junction box 400. The BM110 is equipped with multiple battery cells (hereinafter referred to as "BC") 112, which consist of lithium-ion secondary batteries. Multiple BCs 112 are arranged inside a housing case (module case) and electrically connected in series via conductive members. This constitutes a single battery pack. The BC 112 is the smallest constituent unit of the BM110. The nominal output voltage of the BC 112 is 3.0 to 4.2 volts, and the average nominal output voltage is 3.6 volts. 【0115】 Multiple BC112s are divided into multiple BCG111s by a predetermined number of units for state management and control purposes. In other words, a predetermined number of BC112s are electrically connected in series to form one BCG111, and multiple BCG111s are electrically connected in series to form one battery pack. 【0116】 Here, the predetermined number of units may be, for example, 4, 6, 10, 12, etc., with equal divisions according to the order of potential from the highest potential side to the lowest battery side, or it may be a combination of 4 and 6, etc., with combined divisions according to the order of potential from the highest potential side to the lowest battery side. 【0117】 To avoid complicating the diagrams, Figure 8 shows two BCG111 cells and three BC112 cells associated with each BCG111, while Figure 9 shows four BC112 cells. However, the actual number of cells in a product is greater than those shown. 【0118】 Furthermore, in this embodiment, the example given is that multiple BCG111s are electrically connected in series, and multiple BC112s in each BCG111 are electrically connected in series. However, multiple BCG111s may be electrically connected in series and in parallel, and multiple BC112s in each BCG111 may be electrically connected directly and in parallel. 【0119】Furthermore, although not shown in the diagram, a mechanical switch (circuit breaker or disconnector) called a service disconnect switch (hereinafter referred to as "SD switch") is provided in the middle of the circuit that electrically connects multiple BC112 in series. For example, if two battery blocks, each having multiple BC112 electrically connected in series, are connected in series to form a BM110, the SD switch is provided in the middle of the electrical wiring between the two battery blocks, which is the midpoint of the multiple BC112. 【0120】 The SD switch is a safety device that disconnects the circuit from the positive terminal to the positive external terminal of the BM110 and the circuit from the negative terminal to the negative external terminal of the BM110 within the BM110, so that service technicians can safely perform maintenance work when no high voltage is applied between the circuit from the positive terminal to the positive external terminal of the BM110 and the circuit from the negative terminal to the negative external terminal of the BM110. 【0121】 《Configuration of Battery Management Device》 The BMS 120 is an electronic control device composed of multiple electronic circuit components. It manages the monitoring and control of the state of the BM 110, and provides the vehicle control device 8 with an allowable charge / discharge amount to control the input and output of electrical energy to the BM 110 by the inverter device 300. Functionally, the BMS 120 is configured in two layers, comprising a BMU 140 which corresponds to the upper (parent) layer and a CMU 130 which corresponds to the lower (child) layer of the BMU 140. The BMU 140 and CMU 130 are configured on a single circuit board and housed in a single electronic circuit enclosure. Alternatively, the BMU 140 and CMU 130 may be configured on separate circuit boards and housed in separate electronic circuit enclosures. In this case, the CMU 130 may be placed near the BM 110, and the BMU 140 may be placed in a position that facilitates communication with the outside of the battery device 100. 【0122】A signal transmission path is provided between the BMU140 and the CMU130, enabling bidirectional communication (exchange of electrical signals (digital signals)) between them. A communication IC147 is provided in the signal transmission path between the BMU140 and the CMU130. The communication IC147 performs signal processing (bit-level modification of the data structure of electrical signals) to match the communication specifications of the CMU130's communication method (described later) with the communication specifications of the serial communication device (UART (Universal Asynchronous Receiver / Transmitter) interface) implemented in the MCU141. 【0123】 Here, the BMU140 and CMU130 have different operating power sources and different reference potentials. Specifically, the CMU130 is powered by the BM110, which is floating above the chassis ground, while the BMU140 is powered by a low-voltage battery for on-board auxiliary equipment (e.g., a 14-volt battery) with the chassis ground as its reference potential. For this reason, an insulating component 132 is provided in the middle of the signal transmission path between the BMU140 and the CMU130, and the signal transmission path on one side of the insulating component 132 is electrically isolated from the signal transmission path on the other side of the insulating component 132. As a result, the BMU140 and the CMU130 are electrically isolated from each other, but signal transmission is possible between the BMU140 and the CMU130 using electrical signals with different reference potentials. 【0124】 Furthermore, an electrically isolated state means that there is no electrical conduction between the signal transmission path on one side of the insulating component 132 and the signal transmission path on the other side, and in this non-conductive section, the electrical signal is converted to another medium signal and transmitted, or that no DC current flows between the signal transmission path on one side of the insulating component 132 and the signal transmission path on the other side, but AC current (electrical signal) flows. 【0125】The example of using a pulse transformer as the insulating component 132 will be explained. A pulse transformer is a converter that converts an electrical signal on the transmitting side into a magnetic signal and transmits it to the receiving side, and converts the magnetic signal back into an electrical signal on the receiving side. Other insulating components such as photocouplers, coupling capacitors, and digital isolators may also be used as the insulating component 132. 【0126】 A photocoupler is an optical element that converts an electrical signal into an optical signal on the light-emitting side and transmits it to the light-receiving side, and converts the optical signal back into an electrical signal on the light-receiving side. A coupling capacitor is a capacitive coupling element that does not conduct direct current but conducts alternating current (electrical signal). A digital isolator is a semiconductor device manufactured using complementary metal-oxide-semiconductor (CMOS) processing technology, which has an insulating section made up of capacitive coupling sections and inductors inside, and is an integrated circuit that outputs an input electrical signal through the insulating section using the same principle as coupling capacitors and pulse transformers. 【0127】 《Configuration of the Cell Monitoring Unit》 The CMU130 is equipped with multiple CMIC131s that operate based on command signals output from the BMU140, or after startup, operate standalone according to a predetermined operation sequence, and mainly perform monitoring and control related to BC112 and its own internal circuit, such as detecting the terminal voltage of BC112, balancing discharge of BC112, diagnosing the state of BC112, and diagnosing whether the internal circuit is operating correctly. 【0128】 The same number of CMIC131 units are provided as there are BCG111 units, and one CMIC131 is assigned to each of the BCG111 units, with one CMIC131 corresponding to each BCG111 unit. The CMIC131 units monitor and control the state of each of the BC112 units that make up the corresponding BCG111 unit. 【0129】Each of the multiple CMIC131s is electrically connected via a power line 125 to the positive terminal of the BC112 with the highest potential among the multiple BC112s that make up the corresponding BCG111, and via a ground line 126 to the negative terminal of the BC112 with the lowest potential, and takes in the voltage between the power line 125 and the ground line 126. The ground line 126 is electrically connected to the chassis and grounded. In the CMIC131, the potential of the ground line 126 becomes the reference potential. The taken voltage is input to the power supply circuit 133. 【0130】 The power supply circuit 133 generates the operating voltage VDD (e.g., 3-5V) of the internal circuits of the integrated circuit from the incoming voltage. The internal circuits include a voltage detection circuit 134, a logic circuit 135, a signal circuit 136, a balancing switch drive circuit 137, etc. In this way, by generating the operating voltage of the internal circuits by taking the voltage between the positive side of the BC112 located at the highest potential and the negative side of the BC112 located at the lowest potential, the power consumed in the BCG111 can be made equal, and imbalances in the charge states of the multiple BC112 constituting the BCG111 can be suppressed. 【0131】 Each of the multiple CMIC131s is equipped with a signal circuit 136. The signal circuit 136 is a communication interface circuit that converts electrical signals (digital signals) input via the signal transmission line into digital data and outputs it to the logic circuit 135, and also converts the digital data output from the logic circuit 135 into electrical signals (digital signals) and outputs it to the signal transmission line. 【0132】Each signal circuit 136 of the multiple CMIC 131s is electrically connected in series and non-isolated via a signal transmission path so that electrical signals (digital signals) are transmitted in series according to the order of the reference potentials of the CMIC 131 (the order of the potentials of the multiple BCG 111s). In other words, the electrical signal, on its forward path, is output from the output side of the signal circuit 136 of the first CMIC 131, which uses the lowest potential as its reference potential, then transmitted and inputted to the input side of the signal circuit 136 of the second CMIC 131, which uses the next highest potential as its reference potential, then output from the output side of the signal circuit 136 of the second CMIC 131, then transmitted and inputted to the input side of the signal circuit 136 of the third CMIC 131, which uses the next highest potential as its reference potential, then output from the output side of the signal circuit 136 of the third CMIC 131, ..., then transmitted and inputted to the input side of the signal circuit 136 of the fourth CMIC 131, which uses the second lowest potential as its reference potential, then outputted from the output side of the signal circuit 136 of the fourth CMIC 131, and finally inputted to the fifth CMIC 131, which uses the highest potential as its reference potential. The signal is transmitted in the following order: first to the input side of signal circuit 136, then back to the input side of signal circuit 136 of CMIC 131, then output from the output side of signal circuit 136 of CMIC 131, then transmitted to the input side of signal circuit 136 of CMIC 131, then output from the output side of signal circuit 136 of CMIC 131, ..., then transmitted to the input side of signal circuit 136 of CMIC 131, then output from the output side of signal circuit 136 of CMIC 131, then transmitted to the input side of signal circuit 136 of CMIC 131, then output from the output side of signal circuit 136 of CMIC 131, and so on. This connection of multiple CMICs 131s in series via a signal transmission path, like a daisy-chain, is called a daisy-chain connection. 【0133】Here, a non-isolated state refers to either a state in which the signal circuits 136 of the two CMIC 131 are electrically conductive and DC and AC currents (electrical signals) output from the output side of one signal circuit 136 of the CMIC 131 flow to the input side of the other signal circuit 136 of the CMIC 131, or a state in which a coupling capacitor is provided between the output side of one signal circuit 136 of the CMIC 131 and the input side of the other signal circuit 136 of the CMIC 131, and DC current does not flow between the output side of one signal circuit 136 of the CMIC 131 and the input side of the other signal circuit 136 of the CMIC 131, but AC currents (electrical signals) do flow. A filter circuit such as a resistor may be provided between the output side of one signal circuit 136 of the CMIC 131 and the input side of the other signal circuit 136 of the CMIC 131. 【0134】 A signal transmission path containing a communication IC is electrically connected to the signal circuit 136 of the CMIC 131, which uses the lowest potential as its reference potential, via an insulating component 132. This configuration allows for the exchange of electrical signals between the CMIC 131, which uses the lowest potential as its reference potential, and the BMU 140. As a result, electrical signals output from the BMU 140 are transmitted to the input side of the signal circuit 136 of the CMIC 131, which uses the lowest potential as its reference potential, via the insulating component 132, and electrical signals output from the output side of the signal circuit 136 of the CMIC 131, which uses the lowest potential as its reference potential, are transmitted to the BMU 140 via the insulating component 132. 【0135】 In this embodiment, we have used as an example a wired signal transmission path in which electrical signals are transmitted back and forth in the following order as the signal transmission path from BMU 140 to BMU 130 through multiple CMIC 131s: 1) transmission from BMU 140 to CMIC 131 with the lowest potential as the reference potential, 2) transmission from CMIC 131 with the lowest potential as the reference potential to CMIC 131 with the highest potential as the reference potential in order of the reference potentials, 3) return at CMIC 131 with the highest potential as the reference potential, and the return path is transmitted in the reverse order of the outward path to CMIC 131 with the lowest potential as the reference potential, and 4) transmission from CMIC 131 with the lowest potential as the reference potential to BMU 140. However, we are not limited to this example. 【0136】 For example, a wired signal transmission path can be used in which electrical signals are transmitted in a loop in one direction in the following order: 1) transmission from BMU 140 to CMIC 131 with the highest or lowest potential as the reference potential, 2) transmission from CMIC 131 with the highest or lowest potential as the reference potential to CMIC 131 with the lowest or highest potential as the reference potential, in order of reference potential, and 3) transmission from CMIC 131 with the lowest or highest potential as the reference potential to BMU 140. In this case, a communication circuit and insulating components must be provided between BMU 140 and CMIC 131 with the highest potential as the reference potential. Alternatively, signal transmission between each of the multiple CMIC 131s and BMU 140 can be performed wirelessly. In this case, an antenna for sending and receiving radio waves, as well as a power supply and signal processing circuit necessary for transmission and reception, are required for each of the multiple CMIC 131s and BMU 140. 【0137】 Furthermore, in the wired signal transmission path of this embodiment, serial communication is employed, in which electrical signals consisting of multiple bits are transmitted one bit at a time continuously through a single signal transmission path. For this reason, the number of signal transmission paths is set to two in a reciprocal signal transmission circuit (one in a loop-shaped signal transmission circuit). However, if it is necessary to transmit flag signals consisting of one or two bits, such as flag signals indicating abnormalities, at a high speed with priority, or if it is necessary to transmit start / stop signals that instruct the start or stop of the CMIC131 separately, the number of signal transmission paths may be increased by one or more. 【0138】 Furthermore, the wired signal transmission path of this embodiment employs a communication method called LIN (Local Interconnect Network). The LIN communication method is a subnetwork of the CAN (Controller Area Network) communication method, and since it is a well-known method, a detailed explanation will be omitted here. 【0139】Multiple command signals are output from the BMU 140 to each of the multiple CMIC 131s. These command signals include, for example, a cell voltage request signal that requests the transmission of the terminal voltage of BC 112, a balancing signal to adjust the charge state of BC 112, a start signal to wake up CMIC 131 from sleep state, a pause signal to sleep back up CMIC 131, an address setting signal to set the communication address of CMIC 131, and an abnormality confirmation signal to check what kind of abnormality is detected by CMIC 131. As mentioned above, depending on the content of the command signal, the signal transmission paths may be separated, for example, the cell voltage request signal, balancing signal, and abnormality confirmation signal may be transmitted through one signal transmission path, while the start signal and pause signal may be transmitted through two signal transmission paths. 【0140】 Each of the multiple CMIC 131s is electrically connected to the positive and negative terminals of the multiple BC112s that make up the corresponding BCG 111 via voltage detection wiring 160. This allows each of the multiple CMIC 131s to capture the terminal voltage (cell voltage) of each of the multiple BC112s that make up the corresponding BCG 111. The voltage detection wiring 160 consists of a harness (insulated wire) between the BC112 and the BMS 120 (connector), and a wiring pattern provided on the circuit board between the connector of the BMS 120 and the CMIC 131. 【0141】 In the voltage detection wiring 160, a cell voltage input resistor (Rc) 121 is provided in the middle of the portion that is part of the wiring pattern of the circuit board, so as to be electrically connected in series between the positive terminal of BC112 and CMIC131, and between the negative terminal of BC112 and CMIC131. A cell voltage input capacitor (Cc) 123 is electrically connected between the CMIC131 side of the cell voltage input resistor 121 provided between the positive terminal of BC112 and CMIC131, and between the CMIC131 side of the cell voltage input resistor 121 provided between the negative terminal of BC112 and CMIC131. 【0142】The low-potential side of the cell voltage input capacitor 123 (the negative terminal side of BC112) is electrically connected to the ground line 126 and grounded. The cell voltage input capacitor 123 is also electrically connected between the CMIC 131 side of the cell voltage input resistor 121, which is located between the negative terminal of BC112 (the lowest potential terminal) and CMIC 131, and the ground line 126. The cell voltage input resistor 121 and the cell voltage input capacitor 123 constitute an RC filter and are provided to suppress noise, mainly ripple voltage, that is superimposed on the cell voltage due to the operation of the inverter device 300. 【0143】 The terminal voltages received by the CMIC 131 are input to the voltage detection circuit 134. The multiple terminal voltages input to the voltage detection circuit 134 are sequentially selected by the multiplexer 1341, which is a selection circuit, converted to a different potential by the differential amplifier 1342, which is a potential converter, and then converted from analog to digital by the analog-to-digital converter 1343, and output to the logic circuit 135, which is a control circuit. The logic circuit 135 includes a measurement unit 1354. Based on the digital values ​​output from the voltage detection circuit 134, the measurement unit 1354 detects the terminal voltages of each of the multiple BC112s that make up the multiple BCG111s. 【0144】 Here, the measurement unit 1354 reads the terminal voltage of each BC112 several times, calculates the average voltage for each BC112, and uses this average voltage as the final terminal voltage of each BC112. The logic circuit 135 is equipped with a register 1351. The measurement unit 1354 temporarily stores the final terminal voltage (digital data) of each BC112 in the register 1351. When the signal circuit 136 receives a command signal from the BMU 140 side regarding the transmission of the terminal voltage of each BC112, the measurement unit 1354 reads the terminal voltage (digital data) of each BC112 from the register 1351 and outputs the read terminal voltage of each BC112 to the signal circuit 136. The signal circuit 136 converts the terminal voltage (digital data) of each BC112 into an electrical signal (digital signal) and transmits it to the signal transmission line. The measuring unit 1354 also controls the selection operation of the multiplexer 1341. 【0145】Each of the multiple CMIC131 adjusts the charge state (discharges the BC112) of the multiple BC112s that make up the corresponding BCG111, based on a command signal (balancing signal) related to adjusting the charge state (SOC) output from the BMU140. 【0146】 Here, a BC112 that requires adjustment of its charge state is, for example, a BC112 whose charge state is higher than a predetermined value (threshold) when comparing the average charge state, which is the average (intermediate) value of the highest and lowest terminal voltages among multiple BC112 terminal voltages, with the charge state of each BC112. Based on the charge state of the BC112 that requires adjustment, the BMU140 determines the discharge time of the BC112 and transmits the data related to the discharge time as a command signal to the CMIC131 corresponding to the BC112 that requires adjustment via the signal transmission circuit. 【0147】 For each BCG111, a bypass (discharge) circuit is electrically connected in parallel between the terminals of each of the multiple BC112s that make up the BCG111, in order to adjust the charge state of the BC112. The bypass circuit is configured to branch off on the BC112 side of the cell voltage input resistor 121 of the voltage detection wiring 160 electrically connected to the positive terminal of the BC112, and to reach the negative terminal of the BC112 via an electrical series connection consisting of one discharge resistor (Rd) 122, a balancing switch (hereinafter referred to as "BSW") 138 and two discharge resistors 122, and to rejoin on the BC112 side of the cell voltage input resistor 121 of the voltage detection wiring 160 electrically connected to the negative terminal of the BC112. The BSW 138 is composed of a MOSFET (metal-oxide-semiconductor field-effect transistor), which is a switching semiconductor element. 【0148】A balancing capacitor (Cd) 124 is electrically connected between the BSW 138 side of the first discharge resistor 122 and the BSW 138 side of the second discharge resistor 122. The low-potential side of the balancing capacitor 124 (the side of the second discharge resistor 122) is electrically connected to the ground line 126 and grounded. Another balancing capacitor 124 is electrically connected between the BSW 138 side of the second discharge resistor 122 of the balancing circuit for BC112, which has the lowest potential, and the ground line 126. The balancing capacitor 124 is provided to suppress the effects of noise such as ripple voltage caused by the operation of the inverter device 300. 【0149】 In this embodiment, we will explain using the example of providing two discharge resistors, but one discharge resistor is also acceptable. The required discharge resistance value is determined by the specifications related to balancing, such as the current value flowing through the discharge resistor and the discharge time, so the number of discharge resistors should be determined according to that resistance value. 【0150】 Furthermore, in this embodiment, the example is given where the discharge resistor 122 is provided outside the CMIC 131 and the BSW 138 is provided inside the CMIC 131, but both the discharge resistor 122 and the BSW 138 may be provided either outside or inside the CMIC 131. 【0151】 A command signal regarding the adjustment of the charge state (regarding the discharge time), transmitted from the BMU 140 to the CMIC 131 corresponding to the BC 112 whose charge state needs adjustment, is received by the signal circuit 136 and input to the logic circuit 135. The logic circuit 135 includes a balancing control unit 1352, which, based on the input command signal, generates a conduction (on) signal for the BSW 138 corresponding to the BC 112 whose charge state needs adjustment and outputs it to the balancing switch drive circuit 137. 【0152】The balancing drive circuit 137 receives the conduction (on) signal output from the logic circuit 135, generates a drive signal for the BSW 138 corresponding to the BC 112 that requires charge state adjustment, and outputs this drive signal to the gate electrode of the BSW 138 corresponding to the BC 112 that requires charge state adjustment. As a result, the BSW 138 corresponding to the BC 112 that requires charge state adjustment conducts (turns on). 【0153】 When the BSW 138 corresponding to the BC cell 112 that requires charge state adjustment is turned on, the bypass circuit corresponding to the BC cell 112 that requires charge state adjustment is electrically connected to the BC cell 112 that requires charge state adjustment. This forms an electrically closed loop, and the BC cell 112 that requires charge state adjustment begins to discharge. When the BC cell 112 that requires charge state adjustment begins to discharge, the current output from the BC cell 112 flows through the discharge resistor 122 and is consumed as heat. As a result, the charge level of the BC cell 112 that requires charge state adjustment decreases, and its charge state is adjusted to approach the average charge state. 【0154】 Each logic circuit 135 of the multiple CMIC 131 is equipped with a diagnostic unit 1353. The diagnostic unit 1353 diagnoses (determines) whether the object to be diagnosed is abnormal or not (normal), and compares the detected operating state or state value of the object to be diagnosed with a preset operating state or threshold. If the operation differs from the preset operation or if the state value exceeds the threshold and falls outside the normal range, it diagnoses (determines) it as abnormal. 【0155】Anomaly diagnosis includes anomaly diagnosis on the BM110 side, that is, a diagnosis of whether the multiple BC112s constituting the BCG111 corresponding to each of the multiple CMIC131b are over-discharged or overcharged, and anomaly diagnosis on the CMU130 side. In the former anomaly diagnosis, the terminal voltage of each BC112 detected by the voltage detection described above is compared with the over-discharge threshold and the over-charge threshold. If the terminal voltage falls below the over-discharge threshold, it is diagnosed as over-discharge, and if the terminal voltage exceeds the over-charge threshold, it is diagnosed as over-charge. The latter anomaly diagnosis includes multiple anomaly diagnoses, such as anomaly diagnosis of the voltage detection circuit 134 (each component of the multiplexer 1341, differential amplifier 1342, and analog-to-digital converter 1343), anomaly diagnosis of the BSW138, open circuit diagnosis of the voltage detection wiring 160, and anomaly diagnosis of whether the internal temperature of the CMIC131 is above the allowable temperature. 【0156】 The diagnostic unit 1353 stores digital data related to the results of each abnormality diagnosis in a register 1351. When it receives a command signal from the BMU 140 requesting the transmission of the abnormality diagnosis results, it reads the digital data related to the abnormality diagnosis results from the register 1351 and outputs it to the signal circuit 136. The signal circuit 136 converts the digital data related to the abnormality diagnosis results into an electrical signal and transmits it to the signal transmission path. 【0157】 As a result, the abnormality diagnosis result is transmitted to the BMU 140, and the necessary action is taken. The necessary action varies depending on the severity of the abnormality diagnosis. If an abnormality occurs in a high-priority abnormality diagnosis, the positive side relay 410 and the negative side relay 420 are opened, and the battery device 100 is disconnected from the load side (inverter device 300 and motor generator 200). 【0158】 Furthermore, if an abnormality occurs during a high-priority anomaly diagnosis and it is necessary to take immediate action, a separate signal transmission path can be provided from the signal transmission path through which the command signals output from the BMU140 are transmitted. This path can then be used to transmit the aforementioned flag signals (1-bit or 2-bit digital signals) indicating the abnormality. 【0159】《Sensor Configuration》 A current sensor 150 is provided in the charge / discharge path from the positive electrode side of the BM110 to the DC positive electrode side of the inverter device 300 (power module) for detecting the current being charged and discharged between the BM110 and the inverter device 300 (power module). 【0160】 In this embodiment, the current sensor 150 is described using a current transformer as an example, but other sensors such as shunt resistors may be used. As the current transformer, a Hall element type is used, which includes a magnetic core that generates magnetic flux by the current flowing through the charge / discharge path, a Hall element inserted in the air gap of the magnetic core through which the magnetic flux generated in the magnetic core passes, and an amplifier that amplifies and outputs the Hall voltage (proportional to the current flowing through the charge / discharge path) generated by the Hall effect of the Hall element in accordance with the magnetic flux passing through the Hall element, but other types of current transformers may be used. The measurement signal (amplified Hall voltage) output from the current transformer is input to the BMU 140. As a result, the BMU 140 can detect the current flowing through the charge / discharge path based on the measurement signal output from the current transformer. 【0161】 In this embodiment, the current sensor 150 is described as being installed inside the battery device 100, but it is also acceptable to install the current sensor 150 inside the junction box 400. 【0162】 Although not shown in the diagram, temperature sensors (e.g., thermistors) are attached to the cases housing the BC112 and BM110. For example, four temperature sensors are used to measure the temperature of the cooling medium (e.g., air) drawn into the case, the temperature of the cooling medium discharged from the case, the maximum temperature of the BC112, and the minimum temperature of the BC112. The temperature measurement signals output from the temperature sensors are input to the CMU130 via signal lines and transmitted from the CMU130 to the BMU140 via a signal transmission path between the CMU130 and the BMU140. 【0163】 In this embodiment, the example given is the transmission of the temperature measurement signal output from the temperature sensor to the BMU 140 via the CMU 130. However, it is also possible to transmit the signal directly to the BMU 140 without going through the CMU 130. 【0164】 《Battery Monitoring Unit Configuration》 The BMU 140 monitors and controls the state of the BM 110 directly and / or via the CMU 130, and also receives the physical state of the BM 110, such as voltage, current, and temperature, directly and / or via the CMU 130, and performs calculation processing of battery information such as the charge state, health state, and allowable charge / discharge amount of the BM 110, as well as safety protection diagnostic processing of the BM 110, and notifies the motor control unit of the vehicle control unit 8 or inverter unit 300 of the battery information to control the inflow and outflow of electrical energy in the BM 110. It also includes a total voltage detection circuit 146 for detecting the voltage between the positive and negative electrodes of the BM 110 (the sum of the voltages of multiple BC 112). 【0165】 Although not shown in the diagram, the BMU140 also includes a power supply circuit (a regulator circuit that steps down the 12-volt voltage supplied from a 14-volt battery to, for example, 5 volts and supplies it to the MCU141 to drive the MCU141) and a ground fault detection circuit (a measuring instrument for detecting whether or not there is an electrical connection (short circuit) between the high-voltage system from the BM110 to the motor generator 200 and the chassis ground, which is the reference potential for the low-voltage system). 【0166】 The MCU 141 includes an input unit 142 for inputting signals, an output unit 143 for outputting signals, a storage unit 144 composed of non-volatile memory, and a processing unit 145 for performing various processes. The input unit 142 is a communication interface unit for inputting transmitted signals and includes an A / D input processing unit 1421, an I / O input processing unit 1422, a CMU communication input unit 1423, and a CAN communication input unit 1424. 【0167】The A / D input processing unit 1421 is one of the signal receiving units provided to receive measurement signals related to parameter information such as the voltage (total voltage) of BM110 output from the total voltage detection circuit 146, the charge / discharge current of BM110 output from the current sensor 150, the temperature of BM110 output from a temperature sensor (not shown), and the ground fault detection signal output from the ground fault detection circuit, via signal lines extending from each sensor and wiring patterns on the circuit board. The measurement signals output from each sensor are analog signals. Therefore, the A / D input processing unit 1421 is equipped with an analog-to-digital converter to convert these analog signals into digital signals, converts the measurement signals output from each sensor from analog signals to digital signals, and outputs these converted digital signals to the processing unit 145. 【0168】 The signals output from each sensor may be directly input to the A / D input processing unit 1421 via dedicated signal lines or wiring patterns on the circuit board. However, depending on the arrangement of each sensor and specifications such as the BMU 140 being provided separately from the CMU 130, existing signal lines may be used for input. For example, the measurement signal output from the temperature sensor can be transmitted to the BMU 140 using the signal transmission path between the CMU 130 and the BMU 140, since the temperature sensor is located on the BM 110. 【0169】 The I / O input processing unit 1422 is one of the signal receiving units provided to receive the return signal of the test signal (1-bit signal) output from the MCU 141 to the daisy-chained signal transmission line in order to detect a break in the signal transmission line of the daisy-chained connection, which is composed of the signal transmission line between the CMU 130 and the BMU 140 and the signal transmission line between the CMIC 131. 【0170】 The CMU communication input unit 1423 is one of the signal receiving units for receiving signals transmitted from the CMU 130 via a daisy-chained signal transmission path. As mentioned above, multiple control devices within the vehicle, including the BMU 140, vehicle control device 8, and inverter device 300 (motor control device), are interconnected via a communication network called CAN (Controller Area Network) and send and receive information from each other. 【0171】 The CAN communication input unit 1424 is one of the signal receiving units that receives signals transmitted via its CAN bus from a higher-level control device, such as the vehicle control device 8 or the inverter device 300 (motor control device). Signals transmitted from the higher-level control device include vehicle start / stop requests, on / off signals based on the operation of the ignition key switch, and signals related to relay information. Each signal input by the input unit 142 is output to the processing unit 145. 【0172】 The output unit 143 is a communication interface unit for outputting signals to be transmitted, and includes an I / O output processing unit 1431, a CMU communication output unit 1432, and a CAN communication output unit 1433. The I / O output processing unit 1431 is one of the signal transmission units provided for outputting signals such as refrigerant control signals, relay control signals, ground fault detection signals, and test signals. The refrigerant control signal is a signal for controlling the operation of the fan when cooling air is blown from the fan to the BM110 to cool multiple BC112s, and is output to the fan's drive circuit. When cooling water or other liquids are used as refrigerant and supplied to the BM110 by a pump to cool multiple BC112s, the refrigerant control signal is a signal for controlling the operation of the pump, and is output to the drive circuit of the motor that drives the pump. 【0173】 The ground fault detection signal is an AC input signal (pulse signal) used to detect a ground fault in the ground fault detection circuit configured in the BMU 140, and is output to the ground fault detection circuit. The relay control signal is a signal to open (turn off) the positive side relay 410 and the negative side relay 420. The positive side relay 410 and the negative side relay 420 are normally controlled by the inverter device 300 (motor control device) or the vehicle control device 8, but in emergencies such as overvoltage of BC112, they can be forcibly operated by the BMU 140. The relay control signal is a signal for this purpose and is output to the drive circuits of the positive side relay 410 and the negative side relay 420. The test signal is a 1-bit signal for detecting a break in the signal transmission path of the daisy-chain connection described above, and is output to the signal transmission path of the daisy-chain connection. 【0174】 The CMU communication output unit 1432 is one of the signal transmission units provided to output signals to the CMU 130. Signals output from the CMU communication output unit 1432 include the various command signals mentioned above, namely the balancing control signal for BC112, command signals related to obtaining the terminal voltage of BC112 and the diagnostic results of BC112 and CMIC131, and start or stop signals for CMIC131. 【0175】 The CAN communication output unit 1433 is one of the signal transmission units provided to output status flags and signals related to the status of the battery device 100 and charge / discharge control to the vehicle control device 8 and inverter device 300 (motor control device) connected to the CAN. The status flags are signals based on the self-diagnosis results of the BMU 140 and the diagnosis results obtained from the CMU 130, and there are flags related to relay cut requests, charge / discharge prohibition requests, and alarm notifications, depending on a predetermined severity level. The information related to the status of the battery device 100 is estimated information calculated by the processing unit 145 based on measurement signals input to the input unit 142 and status information of the BC 112 stored in the storage unit 144, and includes SOC (State of Charge), SOH (State of Health), and allowable charge / discharge power or current. 【0176】 The processing unit 145 comprises an application processing unit 1451 and a basic processing unit 1452. The application processing unit 1451 comprises a battery information calculation processing unit 1451a and a battery safety protection diagnostic processing unit 1451b. The battery information calculation processing unit 1451a holds a characteristic table of BC112 and calculates the state value of BM110, control values ​​for controlling the charging and discharging of BM110, and control values ​​for adjusting the charging state of BC112 from the parameter information input via the A / D input processing unit 1421 and the CMU communication input unit 1423. 【0177】Parameter information includes output information from the total voltage detection circuit 146, output information from the current sensor 150, output information from a temperature sensor (not shown), and information on the terminal voltages of multiple BC112s obtained from the CMU 130. State values ​​for the BM110 include the voltage (total voltage) of the BM110, the charge / discharge current of the BM110, the temperature of the BM110, the state of charge (SOC) of the BM110, the state of heat (SOH) of the BM110, and the output (power) of the BM110. The control value for controlling the charge / discharge of the BM110 is the allowable charge / discharge power. The control value for adjusting the charge state of the BC112 is the discharge time for the BC112 to be discharged, calculated based on a comparison between the average value of the SOCs of multiple BC112s and the SOC of each of the multiple BC112s, in order to equalize the SOCs of multiple BC112s. 【0178】 The battery safety protection diagnostic processing unit 1451b diagnoses abnormalities in the input unit 142, output unit 143, total voltage detection circuit 146, current sensor 150, temperature sensor, the aforementioned daisy-chain connected signal transmission path, CAN, ground fault detection circuit, the aforementioned fan or pump, positive-side relay 410, and negative-side relay 420, based on test signals, status values, and operation information input via the A / D input processing unit 1421 and I / O input processing unit 1422. 【0179】 Furthermore, the battery safety protection diagnostic processing unit 1451b diagnoses abnormalities in the storage unit 144 based on information exchange with the storage unit 144. In addition, the battery safety protection diagnostic processing unit 1451b diagnoses abnormalities in the BM 110 from the status value of the BM 110 calculated by the battery information calculation processing unit 1451a. If the diagnostic results indicate an abnormality, or if there is an abnormality in the diagnostic results obtained from the CMU 130, the aforementioned status flag is set and this is notified to the higher-level control unit via CAN communication, and control such as relay cut, which opens the positive-side relay 410 and the negative-side relay 420 as necessary is performed. If a shutdown request is output to the BMU 140 via CAN communication from the higher-level control unit, the start / stop sequence processing unit 1452a of the basic processing unit 1452, which will be described later, stops the operation of the MCU 141. 【0180】Furthermore, if the battery safety protection diagnostic processing unit 1451b detects an abnormality through diagnosis, it stores information about the abnormality, the state value of the BM110 at the time the abnormality occurred, etc., in the storage unit 144. At this time, the battery safety protection diagnostic processing unit 1451b stores a diagnostic code indicating the type of abnormality and its severity in association with it. For example, if the abnormality detected by the diagnosis by the battery safety protection diagnostic processing unit 1451b is an overheating abnormality where the temperature of the BM110 exceeds a predetermined threshold, an overvoltage (overcharge) abnormality where the voltage (charge) of the BM110 exceeds a predetermined threshold, or an overcurrent abnormality where the charge / discharge current of the BM110 exceeds a predetermined threshold, it is stored as severity 1; if it is an overdischarge abnormality where the BM110 discharges beyond a predetermined threshold, it is stored as severity 2; and if it is an abnormality where the operating value (rotation speed) of the cooling means (fan or pump) of the BM110 is not within the normal range, it is stored as severity 3. 【0181】 Overvoltage (overcharging) and overdischarge are determined by comparing the voltage (total voltage) of BM110 with its corresponding threshold value, and by comparing the terminal voltage (cell voltage) of BC112 in CMU130 with its corresponding threshold value. If an abnormality is detected in either of these methods, the device is judged to be abnormal. 【0182】 Here, severity level 1 is an operational shutdown level where operation cannot be continued. In this case, the positive-side relay 410 and the negative-side relay 420 are opened, and the electrical connection between the BM110 and the inverter device 300 is disconnected. Severity level 2 is a level where charging and discharging of the BM110 is prohibited. In this case, charging and discharging of the BM110 may be restarted depending on the conditions. Severity level 3 is a management level with little impact on operation. In this case, an alarm is issued, the amount of charging and discharging of the BM110 is limited, or the BM110 is actively cooled. 【0183】The basic processing unit 1452 includes a start / stop sequence processing unit 1452a that executes processing to start and stop the MCU 141 based on command signals from a higher-level control unit. When an ON signal based on the operation of the ignition key switch, which is a vehicle start / stop request, is input to the CAN communication input unit 1424 from the vehicle control unit 8 via CAN, the start / stop sequence processing unit 1452a starts an internal power supply circuit (not shown) and supplies power to the internal circuit of the MCU 141 to start the MCU 141. 【0184】 Furthermore, when an OFF signal is input to the CAN communication input unit 1424, the start / stop sequence processing unit 1452a stops the power supply circuit and stops the power supply to the internal circuit of the MCU 141, thereby stopping the MCU 141. Also, when the MCU 141 starts up, the start / stop sequence processing unit 1452a outputs flag information such as the completion of control preparation for the BMU 140 via CAN from the CAN communication output unit 1433 to the vehicle control device 8 and the inverter device 300 (motor control device). 【0185】 The memory unit 144 is composed of non-volatile memory that can maintain memory even without a power supply, and stores calculation information from the battery information calculation processing unit 1451a, information obtained from the CMU 130 (status values ​​such as terminal voltage of BC112 and diagnostic results), diagnostic results from the battery safety protection diagnostic processing unit 1451b, and correspondence information between diagnostic codes indicating the nature of abnormalities and their severity in the event of an abnormality. The memory unit 144 also stores information such as the lifetime number of startups accumulated each time the BMU 140 (MCU 141) is started up. 【0186】In this modified example, as in the previous example, a path resistance calculation for identifying the BM110 is performed for a specific voltage detection wire 160 among the voltage detection wires 160. The path resistance calculation for the specific voltage detection wire 160 is performed by the CMIC 131 corresponding to the specific voltage detection wire 160. Depending on the number of BCs connected in series, there may be CMICs that do not perform the path resistance calculation for the specific voltage detection wire. The basic operation in calculating the path resistance of a specific voltage detection wiring 160 is the same as in the previous example. The CMIC 131, which performs the path resistance calculation, calculates the path resistance of the specific voltage detection wiring 160 in the measurement unit 1354 of the logic circuit 135 based on the terminal voltage of BC 112 detected by the voltage detection circuit 134. The diagnostic unit 1353 then diagnoses (determines) whether the calculated path resistance value is within a predetermined range of resistance values ​​that were determined and stored in advance when the BM 110 and BMS 120 were matched. The diagnostic result (identification) flag (for example, 1-bit data consisting of two values, "0" and "1") and the calculated path resistance value are transmitted from the signal circuit 136 to the MCU 141 of the BMU 140 via the signal transmission line. The terminal voltage of BC112 detected to calculate the path resistance of the specific voltage detection wiring 160 is the average value of the terminal voltages of BC112 detected during two discharges performed by controlling the on / off state of the BSW138, similar to the operation in the previous example. The on / off state of the BSW138 is controlled by a command output from the BS control unit 1352 to the BSW drive circuit 137. The two discharge patterns performed by the on / off control of the BSW138 differ depending on the number of BC112s connected in series, and are the same as the discharge patterns shown in Figure 2 of the previous example. 【0187】The diagnostic result (identification) flag transmitted from the CMIC 131, which performs the path resistance calculation, and the calculated path resistance value are input to the battery safety protection diagnostic processing unit 1451b via the input unit 142 (CMU communication input unit 1423). Based on the diagnostic (identification) flag from the CMIC 131 that performs the path resistance calculation, the battery safety protection diagnostic processing unit 1451b determines whether the correct BM 110 is connected to the BMS 120 (for example, whether all the diagnostic (identification) flags from the CMIC 131 that performs the path resistance calculation are flags "1" indicating correct resistance values), and transmits the result to the higher-level vehicle control device 8 via CAN from the output unit 143 (CAN communication output unit 1433). This result, along with the diagnostic (identification) flag and path resistance value from the CMIC 131 that performs the path resistance calculation, are stored in the storage unit 144. Furthermore, the determination of whether the correct BM110 is connected to the BMS120 may be performed by transmitting a diagnostic (identification) flag and path resistance value from the CMIC131, which performs path resistance calculation, to the vehicle control device 8. Alternatively, the battery safety protection diagnostic processing unit 1451b may also perform a diagnosis based on the path resistance value from the CMIC131, which performs path resistance calculation, to determine whether the path resistance value is within a predetermined range of resistance values ​​that have been stored in advance, and then check whether it matches the diagnostic (identification) flag from the CMIC131 that performs path resistance calculation. Although this is a redundant process, if they do not match, the path resistance calculation can be redone, thereby improving the safety and reliability of the battery device 100. 【0188】The specific path resistance calculation is performed when the ignition key switch is turned on for the first time after the BM110 and BMS120 are electrically connected via the voltage detection wiring 160, and before the relay is switched on (when the voltage of the BM110, which is not connected to a load, is in a stable state). As shown in the timing chart of Figure 11, when the ignition key switch is turned on, the BMU140 is started, and a start signal is sent from the start / stop sequence processing unit 1452a to the signal transmission line via the output unit 143 (CMU communication output unit 1432). The start signal is sent to each CMIC131 via the signal transmission line. As a result, the CMIC131 is started, and after initialization, initial diagnosis, and measurement of the terminal voltage (cell voltage) of BC112, it performs the path resistance calculation of the specific voltage detection wiring 160, as in the previous example, and sends the diagnosis (identification) flag and path resistance value to the BMU140 as described above. In addition to this, the CMIC 131 also transmits initial diagnostic results and terminal voltages of the BC 112. As mentioned above, the BMU 140 determines whether the correct BM 110 is connected to the BMS 120 based on the diagnostic (identification) flag from the CMIC 131 which performs path resistance calculation, and transmits the result to the vehicle control device 8. If the vehicle control device 8 determines that there are no problems with charging and discharging the battery device 100, including these other diagnostic results, it controls the positive side relay 410, the negative side relay 420, and the pre-charge relay 430 to switch on, electrically connecting the battery device 100 and the inverter device 300. After this, the battery device 100 transitions from the startup / initialization mode to the normal mode and is charged and discharged. Note that the relay switching control may be performed by the BMS 120 or by the motor control device of the inverter device 300. Furthermore, the identification of BM110 may be performed not only the first time the ignition key switch is turned on after BM110 and BMS120 are electrically connected via the voltage detection wiring 160, but also each time the ignition key switch is turned on from the next time onward. 【0189】The selection of specific voltage detection wiring 160 is carried out in advance when the BM110 and BMS120 are matched. During each of the two discharge cycles performed by controlling the on / off state of the BSW138 as described above, voltage detection wiring 160 corresponding to the BC112 is selected, which allows for the detection of the terminal voltage for calculating the path resistance. The specific voltage detection wiring 160 selected may be completely different depending on the number of BC112s connected in series, or some may be the same while others are different. The number of specific voltage detection wirings 160 selected may also be completely different or the same depending on the number of BC112s connected in series. 【0190】 In this modified example, the path resistance of a specific voltage detection wiring 160 is calculated to identify BM110. However, at the same timing (the specific path resistance calculation timing shown in Figure 11), the path resistance calculation of the voltage detection wiring 160 necessary to correct the terminal voltage of BC112 detected by the voltage detection circuit 134 may also be performed. In this case, the voltage detection wiring 160 differs from the specific voltage detection wiring 160 used to identify the BM110, and is: 1) a voltage detection wiring 160 electrically connected to the positive side of the BC112 with the highest potential; 2) a voltage detection wiring 160 electrically connected to the negative side of the BC112 with the lowest potential; and 3) a voltage detection wiring 160 electrically connected to the boundary of potentialally adjacent CMIC131, that is, the negative side of the lowest BC112 constituting the BCG111 corresponding to the potentialally higher CMIC131, and the positive side of the highest BC112 constituting the BCG111 corresponding to the potentialally lower CMIC131. 【0191】 This disclosure can be used in monitoring devices and power supply systems for monitoring batteries. 【0192】 A Monitoring device B Battery b1-B60 Battery cells C First contactor D Second contactor E Load F Voltage detection unit G Control unit L1-L61 Voltage detection lines R1-R61 Discharge resistors

Claims

A monitoring device for a battery comprising multiple battery cells electrically connected in series, A voltage detection unit is electrically connected to a plurality of battery cells via predetermined voltage detection lines and detects the electrode voltages of the plurality of battery cells, Multiple discharge circuits for forcibly discharging multiple battery cells, An evaluation unit calculates the resistance value of the voltage detection line as a path resistance value based on the electrode voltage when a specific battery cell is forcibly discharged by multiple discharge circuits and the electrode voltage when the battery cell is not forcibly discharged, and evaluates the validity of the battery based on the path resistance value. A monitoring device equipped with the following features. 　 A battery monitoring device comprising the aforementioned plurality of battery cells and electrically connected to the load side via a contactor, Multiple input terminals electrically connected to one pole and the other pole of each of the multiple battery cells via voltage detection lines, A voltage acquisition circuit is electrically connected to the plurality of input terminals and takes the cell voltage of each of the plurality of battery cells, A control circuit having a voltage detection unit that detects the cell voltage acquired by the voltage acquisition circuit, The control circuit has a voltage detection line resistance calculation unit that calculates the resistance value of a specific voltage detection line as identification information for the battery when the voltage detection line is electrically connected to the plurality of input terminals and the monitoring device is started for the first time thereafter. The monitoring device according to claim 1. 　 The voltage detection line resistance calculation unit calculates the resistance value of the specific voltage detection line before the contactor is turned on. The monitoring device according to claim 2. 　 Furthermore, it has a communication circuit, The control circuit outputs information regarding the resistance value of the specific voltage detection line calculated by the voltage detection line resistance calculation unit from the communication circuit before the contactor is closed. The monitoring device according to claim 3. 　 Furthermore, it has an electrically series connection circuit of a resistor and a switch, provided corresponding to each of the plurality of battery cells and electrically connected between the input terminals to which the corresponding battery cells are electrically connected. The voltage detection line resistance calculation unit is, The voltage difference in the specific voltage detection line is calculated using the voltage detected when the switch corresponding to the battery cell to which the specific voltage detection line is electrically connected is opened and closed according to a predetermined opening and closing pattern, The current flowing through the aforementioned specific voltage detection line is calculated, The resistance value of the specific voltage detection line is calculated from the calculated voltage difference and current. A monitoring device according to any one of claims 2 to 4. 　 At least the voltage input circuit, a part of the series connection circuit, and the control circuit are composed of integrated circuits. The predetermined opening and closing pattern is: The aforementioned specific voltage detection line is a voltage detection line electrically connected between two battery cells that are electrically adjacent in the series connection of the plurality of battery cells. Of the two electrically adjacent battery cells, the higher-potential battery cell corresponds to the odd-numbered battery cell in the electrical series connection order of the plurality of battery cells, and the lower-potential battery cell corresponds to the even-numbered battery cell. If the relationship between the number of battery cells Nb and the number of channels Nc into which the cell voltage of the integrated circuit is input is Nc = Nb + 1, A first pattern in which the switch corresponding to the high-potential battery cell is closed and the switch corresponding to the low-potential battery cell is opened, This results in a second pattern in which the switches corresponding to the high-potential battery cell and the low-potential battery cell are opened. The aforementioned specific voltage detection line is a voltage detection line electrically connected between two battery cells that are electrically adjacent in the series connection of the plurality of battery cells. Of the two electrically adjacent battery cells, the higher-potential battery cell corresponds to the odd-numbered battery cell in the electrical series connection order of the plurality of battery cells, and the lower-potential battery cell corresponds to the even-numbered battery cell. When the relationship between the number of battery cells Nb and the number of channels Nc into which the cell voltage of the integrated circuit is input is Nc = Nb, A third pattern in which the switch corresponding to the high-potential battery cell is opened and the switch corresponding to the low-potential battery cell is closed, The second pattern described above is: The monitoring device according to claim 5. 　 The control circuit further includes a voltage detection line abnormality diagnosis unit that detects abnormalities in the specific voltage detection line, The voltage detection line abnormality diagnosis unit is, The resistance value of the specific voltage detection line calculated by the voltage detection line resistance calculation unit is compared with a preset abnormality diagnosis resistance threshold. If the resistance value of the aforementioned specific voltage detection line is higher than the abnormality diagnosis resistance threshold, it is determined that there is an abnormality in the voltage detection line. A monitoring device according to any one of claims 2 to 4. 　 Furthermore, it has a communication circuit, The aforementioned control circuit is If the voltage detection line abnormality diagnosis unit determines that there is no abnormality in the specific voltage detection line, it outputs a normal flag from the communication circuit. If the voltage detection line abnormality diagnosis unit determines that there is an abnormality in the specific voltage detection line, the communication circuit outputs an abnormality flag and information that identifies the abnormal voltage detection line. The monitoring device according to claim 7. 　 The monitoring device according to claim 1, wherein the evaluation unit evaluates the validity of the battery before the contactor provided between the battery and the load is closed. 　 The monitoring device according to claim 1 or 9, wherein the evaluation unit notifies an external party of the evaluation result of the validity of the battery. 　 The monitoring device according to claim 1 or 9, wherein the evaluation unit forces a discharge of a battery cell whose cell number is odd or even, as a specific battery cell. 　 A power supply system comprising the monitoring device according to claim 1 or 9 and the battery to be monitored.

Images