JP5696593B2 - Battery monitoring device - Google Patents

Description

  The present invention relates to a battery monitoring device that monitors an assembled battery configured by connecting a plurality of battery cells in series.

  Conventionally, in an assembled battery, from the viewpoint of ensuring safety during maintenance or the like, a predetermined number of battery cells are grouped as unit batteries, and the connection part is physically connected to a part of the connection part that connects adjacent unit batteries. Service plugs, fuses, and the like for cutting are provided. In addition, a service plug is a plug which makes an electrical connection state between adjacent unit batteries by attaching, and makes an electrical connection state between adjacent unit batteries by removing.

  As a battery monitoring device for monitoring the assembled battery configured as described above, a plurality of monitoring units provided corresponding to each unit battery in the assembled battery, and an instruction signal for instructing monitoring to each monitoring unit are output. It is composed of a control unit composed of a microcomputer (hereinafter simply referred to as a microcomputer).

  Here, since the control unit is driven at a low voltage with respect to the monitoring unit that is driven at a high voltage, if all the monitoring units are individually connected to the control unit, all the units between each monitoring unit and the control unit It is necessary to ensure insulation. For this reason, instead of connecting all the monitoring units to the control unit, a part of the monitoring units and the control unit are connected, and a communication line between the monitoring unit connected to the control unit and the adjacent monitoring unit is used. A configuration (daisy chain connection) in which an instruction signal or the like from the control unit is transmitted between the monitoring units by connection is preferable.

  However, in this case, for example, even if the service plug provided between the unit batteries in the assembled battery is removed and the unit batteries are disconnected, the monitoring units corresponding to the unit batteries connected via the service plug The communication line may become a current detour path, which is a problem in safety.

  In contrast, for example, in the battery monitoring device of Patent Document 1, when a diode or a switch is provided on a communication line between monitoring units corresponding to unit batteries connected via a service plug, and the service plug is removed, This prevents unnecessary current from flowing in the communication line between the monitoring units.

JP 2009-14498 A

  However, in the case of a configuration in which a diode or the like is provided on a communication line between monitoring units corresponding to unit batteries connected via a service plug or the like as in the battery monitoring device of Patent Document 1, when the service plug or the like is removed, The potential at the connection between the service plug and the unit battery may become unstable, and communication in the monitoring unit may be interrupted. Thus, when communication in the monitoring unit is interrupted, there is a problem that the control unit cannot properly control the monitoring unit and the reliability of the battery monitoring device is reduced.

  An object of the present invention is to provide a battery monitoring apparatus capable of maintaining communication in a monitoring unit when a connection part of adjacent unit batteries in an assembled battery is disconnected while ensuring safety. To do.

  In order to achieve the above object, according to the first aspect of the present invention, an assembled battery composed of a plurality of battery cells connected in series is provided corresponding to each unit battery grouped for each predetermined number of battery cells. A plurality of monitoring units for monitoring the corresponding unit battery, and a monitoring control means for outputting an instruction signal for instructing the monitoring unit to monitor, and obtaining an instruction signal from the monitoring control means among the plurality of monitoring units A battery monitoring device in which a unit is configured to transmit a signal including an instruction signal to an adjacent monitoring unit via a signal transmission unit, and at least some of the unit batteries in the assembled battery are Are connected in series to adjacent unit cells by a connection part that can be physically disconnected, and the assembled battery is supplied with electric power from the assembled battery in conjunction with the disconnection of the connection part. The connection with the air load is configured to be cut off, and the signal transmission means cuts off between the monitoring units corresponding to the unit batteries connected at the connection unit when the connection unit is disconnected. And a transmission path switching means for switching the transmission path of the signal including the instruction signal in the monitoring unit corresponding to the unit battery connected at the connection unit from the adjacent monitoring unit to the monitoring control means. It is characterized by.

  According to this, when the connection part of the adjacent unit batteries in the assembled battery is disconnected, the monitoring units corresponding to the unit batteries connected by the disconnected connection part are shut off. Therefore, it is possible to prevent an unnecessary current from flowing through the signal transmission means.

  In addition, when the connection of adjacent unit batteries in the assembled battery is disconnected, the signal transmission path including the instruction signal in the monitoring unit corresponding to the unit battery connected by the disconnected connection is adjacent. Since the monitoring unit is switched to the monitoring control means, communication in the monitoring unit can be maintained.

  Therefore, even if the connection part of the adjacent unit batteries in the assembled battery is disconnected, communication in the monitoring unit can be maintained while ensuring safety.

  Specifically, in the invention according to claim 2, in the battery monitoring device according to claim 1, the battery monitoring device further comprises switching control means for controlling the operation of the transmission path switching means, and the transmission path switching means is connected by the connecting portion. A signal transmission unit for transmitting a signal including an instruction signal between the monitoring unit corresponding to the unit battery to be monitored and the monitoring control unit, and a first unit for conducting and blocking between the monitoring units corresponding to the unit cells connected by the connection unit The switching control means has one connection opening / closing part, and when the connection part is disconnected, the monitoring units corresponding to the unit cells connected by the connection part are shut off.

  According to this, it is possible to specifically realize a battery monitoring device capable of maintaining communication in the monitoring unit while ensuring safety.

  Further, as in the invention described in claim 3, in the battery monitoring device described in claim 2, the signal transmission unit is provided between the monitoring unit corresponding to the unit battery connected by the connecting unit and the monitoring control unit. A resistance for suppressing the flowing current to be equal to or less than a predetermined current value, and a configuration having a second connection opening / closing portion for conducting and blocking between the monitoring unit corresponding to the unit battery connected by the connecting portion and the monitoring control means, Preferably, when the connection unit is disconnected, the switching control unit conducts between the monitoring unit corresponding to the unit battery connected by the connection unit and the monitoring control unit.

  According to a fourth aspect of the present invention, in the battery monitoring device according to the third aspect, the first connection opening / closing part and the second connection opening / closing part are constituted by a photorelay.

  According to this, since it can conduct | electrically_connect and interrupt | block in the state which ensured the insulation between the adjacent monitoring units and between the monitoring unit and the monitoring control means, safety | security can fully be ensured.

Further, in the battery monitoring device according to any one of claims 1 to 4 , as in the invention according to claim 5 , the connection unit that can be physically disconnected can be cut off between adjacent unit cells. It can be a service plug.

Moreover, in the battery monitoring device according to any one of claims 1 to 4 , as in the invention according to claim 6 , the connection unit that can be physically disconnected can be cut off between adjacent unit cells. It can be a fuse.

1 is an overall configuration diagram of an assembled battery control system including a battery monitoring device according to a first embodiment. It is a whole block diagram of the assembled battery control system containing the battery monitoring apparatus which concerns on 2nd Embodiment. It is a whole block diagram of the assembled battery control system containing the battery monitoring apparatus which concerns on 3rd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIG. FIG. 1 shows an overall configuration of an assembled battery control system including a battery monitoring device according to the present embodiment.

  In the present embodiment, the battery monitoring device 2 of the present invention is applied to the control system for the assembled battery 1 which is an in-vehicle high voltage battery. As shown in FIG. 1, the assembled battery control system of the present embodiment includes an assembled battery 1 and a battery monitoring device 2 as main components.

  The assembled battery 1 of this embodiment supplies electric power to various electric devices (not shown) such as a motor for driving a vehicle. The positive electrode end and the negative electrode end of the assembled battery 1 are connected to various electric loads via a system main relay SMR. The system main relay SMR conducts and cuts off between the assembled battery 1 that is a high-voltage battery and various electric devices that are high-voltage using devices according to a control signal from the outside. In conjunction with the removal of the S / P, the system main relay SMR is turned off, and the assembled battery 1 and various electric devices are disconnected.

  The assembled battery 1 is formed by connecting battery cells 1a made of lithium ion batteries or the like in series, and is configured as a series connection body of a plurality of unit batteries B1 to Bn grouped for each predetermined number of battery cells adjacent to each other. . For convenience of explanation, in the present embodiment, as shown in FIG. 1, an example in which the assembled battery 1 is configured by a series connection body of four unit batteries B1 to B4 will be described.

  At least some of the unit batteries B1 to Bn in the assembled battery 1 are connected to adjacent unit batteries via the service plug S / P. In the present embodiment, the unit battery is between the positive terminal of the battery cell 1a having the highest voltage in the unit battery B2 and the negative terminal of the battery cell 1a having the lowest voltage in the unit battery B3 adjacent to the unit battery B2. A service plug S / P for connecting B2 and unit battery B3 is provided.

  The service plug S / P corresponds to a connection part that can physically disconnect the unit battery B2 and the unit battery B3 during maintenance or the like, and is adjacent by removing the service plug S / P. The connection between unit batteries is configured to be cut off. As a result, safety is improved during maintenance such as battery replacement.

  A battery monitoring device 2 that monitors the state (overdischarge state and overcharge state) of each of the unit batteries B1 to B4 is connected to the assembled battery 1 configured in this manner through the detection line.

  The battery monitoring device 2 is a device having an overcharge / discharge detection function for monitoring the state of each battery cell 1a of the unit batteries B1 to Bn. The overdischarge state means an abnormal state in which the voltage at both ends of each battery cell 1a becomes an excessively low voltage that causes a decrease in reliability. In the overcharge state, the voltage at both ends of each battery cell 1a is reliable. It means an abnormal state that results in an excessively high voltage that causes a decrease in.

  Specifically, the battery monitoring device 2 includes a monitoring unit U1 to Un provided corresponding to each unit battery B1 to Bn, and a microcomputer 20 that controls the operation of various control devices including the monitoring units U1 to Un. Configured. For convenience of explanation, in the present embodiment, as shown in FIG. 1, an example in which four monitoring units U1 to Un are configured in accordance with the unit batteries B1 to B4 will be described.

  The monitoring units U1 to U4 of the present embodiment are connected to the bipolar terminals of the battery cells 1a of the corresponding unit batteries B1 to B4 via detection lines, and indicate instruction signals (for example, instructing monitoring of the unit batteries B1 to B4) The overcharged state and the overcharged state of each battery cell 1a in the unit batteries B1 to B4 are monitored according to the clock signal CLK), and the monitoring result is output as an output signal to the microcomputer 20 described later.

  Specifically, when each of the monitoring units U1 to U4 monitors whether or not it is in an overdischarged state, the voltage between both electrodes of each battery cell 1a in the unit batteries B1 to B4 is preliminarily in the overdischarged state. It is determined whether the voltage is lower than the overdischarge threshold voltage set for the voltage. And when the voltage between the both electrodes of each battery cell 1a in unit battery B1-B4 is lower than the said threshold voltage, a monitoring result is made into an overdischarge state, and when it is more than a threshold voltage, a monitoring result is made into a normal state. .

  Moreover, when each monitoring unit U1-U4 monitors whether it is an overcharge state, the voltage between the both electrodes of each battery cell 1a in unit battery B1-B4 is preset to the voltage at the time of an overcharge state. It is determined whether or not the overcharge threshold voltage is higher. And when the voltage between the both electrodes of each battery cell 1a in unit battery B1-B4 is higher than the said threshold voltage, a monitoring result is made into an overcharge state, and when less than a threshold voltage, a monitoring result is made into a normal state. .

  The monitoring units U1 to U4 receive an instruction signal (monitoring instruction signal) for instructing monitoring of the corresponding unit batteries B1 to B4 and input units (not shown) for acquiring output signals of adjacent monitoring units U1 to U4. ), An output unit (not shown) for outputting a monitoring instruction signal and an output signal to the adjacent monitoring units U1 to U4.

  The microcomputer 20 is a microcomputer including an MPU, a ROM, an EEPROM, a RAM, an input / output unit (not shown), and the like, and executes various processes according to a program stored in a storage unit in the ROM or the like. Note that a monitoring unit U4, which is a control device, a transmission path switching unit 22 described later, and the like are connected to the input / output unit of the microcomputer 20.

  The microcomputer 20 of the present embodiment outputs a monitoring instruction signal instructing monitoring of each battery cell 1a to the monitoring unit U4, acquires an output signal output from each of the monitoring units U1 to U4, and obtains the acquired output signal. It is configured to control various control devices accordingly.

  Specifically, the microcomputer 20 of this embodiment is connected to the monitoring unit U4 corresponding to the unit battery B4 having the highest voltage among the monitoring units U1 to U4 via the insulating element (for example, photocoupler) 21. Has been. The microcomputer 20 and the monitoring unit U4 of the present embodiment are connected so as to be able to communicate in both directions. A monitoring instruction signal is output from the microcomputer 20 to the monitoring unit U4, and each monitoring unit is transmitted from the monitoring unit U4 to the microcomputer 20. An output signal including the monitoring results of U1 to U4 is output.

  In addition, each of the monitoring units U1 to U4 is sequentially connected by a communication line so as to be communicable between adjacent monitoring units by a daisy chain connection method. More specifically, the monitoring unit U4 connected to the microcomputer 20 is connected to the adjacent monitoring unit U3, the monitoring unit U3 is connected to the adjacent monitoring unit U2, and the monitoring unit U2 is connected to the adjacent monitoring unit U1. It is connected.

  By adopting a configuration in which the adjacent monitoring units U1 to U4 are connected via the communication line in this way, the monitoring instruction signal acquired by the monitoring unit U4 from the microcomputer 20 is changed to the monitoring unit U3 → the monitoring unit U2 → the monitoring unit U1. The output signals of the monitoring units U1 to U4 can be output to the microcomputer 20 via the monitoring unit U4.

  Here, among the unit batteries B1 to B4, between the monitoring units U2 and U3 corresponding to the unit batteries B2 and B3 connected via the service plug S / P (connection portion that can be physically disconnected) A transmission path switching unit 22 that switches a transmission path of a signal including the monitoring instruction signal is provided. The “monitoring unit corresponding to the unit battery” means that among the battery cells 1a constituting the unit battery, at least the positive terminal of the battery cell 1a having the highest voltage and the negative terminal of the battery cell 1a having the lowest voltage are electrically connected. And a monitoring unit that monitors the battery state of at least the entire unit battery. In this embodiment, the communication line connecting the monitoring units U1 to U4 and the transmission path switching unit 22 constitute a signal transmission unit.

  The transmission path switching unit 22 is connected to the microcomputer 20 and constitutes a transmission path switching unit that is controlled according to a signal from the microcomputer 20. The transmission path switching unit 22 of the present embodiment includes a signal transmission unit 221 that transmits a signal including a monitoring instruction signal between the monitoring unit U2 and the microcomputer 20, and a first connection that connects and disconnects between the monitoring units U2 and U3. An opening / closing part 222 is provided.

  The signal transmission unit 221 includes a resistor 221a for suppressing the current flowing between the monitoring unit U2 and the microcomputer 20 to a predetermined current value, and a second connection opening / closing unit for conducting and blocking between the monitoring unit U2 and the microcomputer 20 221b is configured.

  In this embodiment, the 1st connection opening / closing part 222 and the 2nd connection opening / closing part 221b are comprised with the photo relay excellent in insulation. The first connection opening / closing unit 222 and the second connection opening / closing unit 221b of the present embodiment are controlled in accordance with a signal from the microcomputer 20.

  In addition, the resistor 221a of the signal transmission unit 221 generates a predetermined current value for a current flowing between the monitoring unit U2 and the microcomputer 20 when the second connection opening / closing unit 221b conducts between the monitoring unit U2 and the microcomputer 20. It is provided to keep it below. The resistance value of the resistor 221a is set so that the current value of the current flowing between the monitoring unit U2 and the microcomputer 20 is equal to or less than a current perception threshold (for example, 3.5 mA) that humans feel painful. ing. In consideration of safety, the resistor 221a is desirably set so that the current flowing between the monitoring unit U2 and the microcomputer 20 is about 3.5 mA which is equal to or less than the current perception threshold. For example, when the voltage across the unit batteries B1 and B2 is 400V, the resistance value of the resistor 221a is set to 115 kΩ or more so that the current flowing between the monitoring unit U2 and the microcomputer 20 is 3.5 mA or less. The

  The microcomputer 20 of this embodiment is configured integrally with a control means for outputting an instruction signal for instructing the monitoring unit to monitor and a control means for controlling various control devices. However, in this embodiment, the monitoring unit in the microcomputer 20 is configured. A configuration (hardware and software) for outputting an instruction signal for instructing monitoring constitutes the monitoring control means 20a, and a configuration (hardware and software) for controlling the transmission path switching unit 22 in the microcomputer 20 provides the switching control means 20b. It is composed.

  The above is the overall configuration of the battery monitoring device 2 according to the present embodiment, and the outline of the operation of the battery monitoring device 2 according to the present embodiment will be described below.

  First, the monitoring process of the overdischarge state and the overcharge state of each battery cell 1a by the battery monitoring device 2 according to the present embodiment will be described.

  The microcomputer 20 outputs a monitoring instruction signal for instructing monitoring of the overdischarge state or the overcharge state of each battery cell 1a to the monitoring unit U4 via the photocoupler 21. When the monitoring instruction signal is taken into the monitoring unit U4, the monitoring unit U4 monitors the unit battery B4 to be monitored according to the monitoring instruction signal, and monitors the output signal (the monitoring instruction signal and the signal indicating the monitoring result). Output to unit U3.

  The monitoring unit U3 to which the output signal output from the monitoring unit U4 is input monitors the unit battery B3 to be monitored according to the monitoring instruction signal, and includes the monitoring result and the monitoring result of the monitoring unit U4. An output signal is output to the monitoring unit U2.

  The monitoring unit U2 monitors the unit battery B2 to be monitored according to the monitoring instruction signal included in the output signal of the monitoring unit U3, and monitors the output signal including the monitoring result and the monitoring results of the monitoring units U3 and U4. Output to unit U1. Further, the monitoring unit U1 monitors the unit battery B1 to be monitored in accordance with the monitoring instruction signal included in the output signal of the monitoring unit U2, and outputs an output signal including the monitoring result and the monitoring results of the monitoring units U2 to U4. Is output to the microcomputer 20 via the communication line of each of the monitoring units U1 to U4 and the photocoupler 21.

  The microcomputer 20 determines whether each battery cell 1a is in an overdischarged state or an overcharged state based on output signals from the monitoring units U1 to U4. And as a result of the determination, when it is determined that the output signal from each of the monitoring units U1 to U4 does not include a monitoring result indicating an overdischarge state or an overcharge state, the monitored unit batteries B1 to B4 are normal. Determine and end the monitoring process. On the other hand, when it is determined that the output signal from each of the monitoring units U1 to U4 includes a monitoring result indicating an overdischarge state or an overcharge state, the monitored unit batteries B1 to B4 are determined to be abnormal.

  Next, switching of a transmission path of a signal including a monitoring instruction signal by the transmission path switching unit 22 which is a characteristic operation of the battery monitoring device 2 according to the present embodiment will be described.

  First, when the service plug S / P is attached, that is, when the unit batteries B2 and B3 are conductive, the first connection opening / closing unit 222 is connected so that the monitoring unit U2 and U3 are conductive by the microcomputer 20. In addition to being turned on, the second connection opening / closing part 221b is turned off so as to interrupt the monitoring unit U2 and the microcomputer 20. Thereby, the transmission path of the signal including the monitoring instruction signal in the monitoring unit U2 becomes the monitoring unit U3.

  On the other hand, when the service plug S / P is removed, that is, when the unit batteries B2 and B3 are cut off, the system main relay SMR is turned off and the assembled battery 1 and various electric devices are cut off. Is done. Then, the microcomputer 20 turns on the second connection opening / closing part 221b so that the monitoring unit U2 and the microcomputer 20 are electrically connected, and turns off the first connection opening / closing part 222 so as to cut off between the monitoring units U2, U3. Is done.

  Thereby, the transmission path of the signal including the monitoring instruction signal in the monitoring unit U2 is switched from the monitoring unit U3 to the microcomputer 20. In this case, monitoring units U2 and U4 are connected to the microcomputer 20, a monitoring instruction signal is output from the microcomputer 20 to the monitoring units U2 and U4, and a signal including the monitoring results of the monitoring units U1 to U4 is output to the microcomputer. 20 is output. Note that the monitoring unit U3 can communicate with the microcomputer 20 via the monitoring unit U4, and the monitoring unit U1 can communicate with the microcomputer 20 via the monitoring unit U2.

  As described above, according to the battery monitoring apparatus of the present embodiment described above, when the service plug S / P provided between the unit batteries B2 and B3 in the assembled battery 1 is removed, the connection is made via the service plug S / P. The monitoring units U2 and U3 corresponding to the unit batteries B2 and B3 that have been disconnected are blocked by the first connection opening / closing unit 222, so that an unnecessarily current flows through the communication line between the monitoring units U2 and U3. This can be suppressed.

  In addition, when the service plug S / P provided between the unit batteries B2 and B3 in the assembled battery 1 is removed, a signal transmission path including an instruction signal in the monitoring unit U2 corresponding to the unit battery B2 is provided. Since the monitoring unit U3 is switched to the microcomputer 20, the communication in the monitoring unit U2 can be maintained.

  Therefore, even if the service plug S / P between the adjacent unit batteries B2 and B3 in the assembled battery 1 is removed, communication in each of the monitoring units U1 to U4 can be maintained while ensuring safety.

  Moreover, in this embodiment, the 1st connection opening / closing part 222 and the 2nd connection opening / closing part 221b are comprised with the photo relay. Thereby, since it can conduct | electrically_connect and interrupt | block in the state which ensured the insulation between monitoring unit U2, U3 and between the monitoring unit U2 and the microcomputer 20, safety | security can fully be ensured.

  When the monitoring unit U2 and the microcomputer 20 are conducted, the system main relay is turned off, so that high voltage noise is suppressed from being generated in the signal between the monitoring unit U2 and the microcomputer 20.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 2 shows the overall configuration of the assembled battery control system including the battery monitoring device according to the present embodiment. In the present embodiment, description of the same or equivalent parts as in the first embodiment will be omitted or simplified.

  In the present embodiment, as shown in FIG. 2, the monitoring units U2 and U3 corresponding to the monitoring units U2 and U3 connected by the service plug S / P are connected via an insulating element 23. In this embodiment, two photocouplers 23a and 23b are used as insulating elements, and bidirectional communication is possible between the monitoring units U2 and U3. In the present embodiment, the communication line connecting the monitoring units U1 to U4 and the insulating element 23 constitute a signal transmission means.

  As in this embodiment, when the monitoring units U2 and U3 are connected by the insulating element 23, the monitoring units U2 and U3 can communicate with each other while ensuring the insulation between the monitoring units U2 and U3. Even if the service plug S / P is removed, communication in the monitoring units U1 to U4 can be maintained while ensuring safety.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 3 shows the overall configuration of the assembled battery control system including the battery monitoring device according to the present embodiment. In the present embodiment, description of the same or equivalent parts as in the first and second embodiments will be omitted or simplified.

  In the present embodiment, as shown in FIG. 3, the microcomputer 20 of the present embodiment includes the monitoring unit U4 corresponding to the unit battery B4 having the highest voltage and the unit having the lowest voltage among the monitoring units U1 to U4. The battery B1 is connected via an insulating element (for example, photocoupler) 21.

  Specifically, the microcomputer 20 and the monitoring unit U4 of this embodiment are communicably connected in a single direction from the microcomputer 20 to the monitoring unit U4, and the microcomputer 20 and the monitoring unit U1 are connected to the monitoring unit U1. To the microcomputer 20 so as to be able to communicate in one direction. A signal including the monitoring instruction signal output from the microcomputer 20 to the monitoring unit U4 is output from the monitoring unit U3 → the monitoring unit U2 → the monitoring unit U1 → the microcomputer 20.

  Further, in the present embodiment, a single photocoupler 23a is used as the insulating element 23 for connecting the monitoring units U2 and U3 corresponding to the monitoring units U2 and U3 connected by the service plug S / P, and the monitoring unit U3 Communication to the monitoring unit U2 is possible in one direction. In the present embodiment, the communication line connecting the monitoring units U1 to U4 and the insulating element 23 constitute a signal transmission means.

  Even if the service plug S / P is removed as in the second embodiment, the configuration in which the monitoring units U4 are communicatively connected between the monitoring units U4 as in the present embodiment, while ensuring the safety, Communication in the monitoring units U1 to U4 can be maintained.

(Other embodiments)
As mentioned above, although embodiment of this invention was described, this invention is not limited to this, Unless it deviates from the range described in each claim, it is not limited to the wording of each claim, and those skilled in the art Improvements based on the knowledge that a person skilled in the art normally has can be added as appropriate to the extent that they can be easily replaced. For example, various modifications are possible as follows.

  (1) In the first embodiment described above, the example in which the first connection opening / closing part 222 and the second connection opening / closing part 221b are configured by photorelays has been described. However, the present invention is not limited to this, and for example, the first connection opening / closing part 222 And the 2nd connection opening-and-closing part 221b can be comprised with a mechanical relay or a MOS switch.

  (2) In each of the above-described embodiments, the example in which the signal transmission unit 221 includes the resistor 221a and the second connection opening / closing unit 221b has been described, but the present invention is not limited to this. For example, when the resistance 221a has a high resistance value of several MΩ or more, the second connection opening / closing unit 221b may be eliminated, and the signal transmission unit 221 may be configured with only the resistor 221a.

  (3) In the second and third embodiments described above, the example in which the insulating element provided between the monitoring units U2 and U3 is configured by a photocoupler has been described. However, the present invention is not limited to this example. A ring capacitor or a coupling transformer can be used.

  (4) In each of the above-described embodiments, an example in which the transmission path switching unit 22 and the insulating element 23 are provided only between the monitoring units U2 and U3 corresponding to the unit batteries B2 and B3 connected by the service plug S / P will be described. However, it is not limited to this.

  For example, in addition to the service plug S / P, the transmission path switching unit 22 and the insulating element 23 are connected between the monitoring units corresponding to the unit batteries connected by any of fuses, bus bars, and wirings that can be physically disconnected. It is good also as a structure which provides.

  Further, between the monitoring units corresponding to the unit batteries connected by the service plug S / P, between the unit battery on the highest voltage side and the microcomputer 20, and between the unit battery on the lowest voltage side and the microcomputer 20 Alternatively, the transmission path switching unit 22 and the insulating element 23 may be provided between the other monitoring units. In this case, considering the increase in the number of parts, the transmission path switching unit 22 and the insulation element 23 are not provided between all the monitoring units, but the transmission path switching unit 22 and the insulation are provided at least partially between the monitoring units. A form in which the element 23 is provided is preferable.

  (5) Moreover, although each above-mentioned embodiment demonstrated the example which monitors both the overdischarge state of each battery cell 1a in the monitoring units U1-U4 of the battery monitoring apparatus 2, and overcharge state, it is limited to this. Not. For example, only one of the overdischarge state and the overcharge state of each battery cell 1a may be monitored by the monitoring units U1 to U4.

  (6) Further, in each of the above-described embodiments, the example in which the battery monitoring device 2 is applied to the in-vehicle high voltage battery has been described, but the present invention is not limited to the in-vehicle high voltage battery, and may be used for other batteries.

1 assembled battery 1a battery cell 2 microcomputer (control means)
20a monitoring control means 20b switching control means 22 transmission path switching section (transmission path switching means)
221 Signal transmission part 221a Resistance 221b Second connection opening / closing part 222 First connection opening / closing part 23 Insulating element 23a Photocoupler 23b Photocoupler B1-Bn Unit battery U1-Un Monitoring unit

Claims (6)

A plurality of monitoring units that are provided corresponding to each unit battery in which a plurality of battery cells connected in series are grouped for each predetermined number of battery cells, and monitor the corresponding unit batteries; A monitoring control unit that outputs an instruction signal for instructing monitoring to the monitoring unit, and the monitoring unit that has acquired the instruction signal from the monitoring control unit among the plurality of monitoring units transmits a signal to the adjacent monitoring unit A battery monitoring device configured to transmit a signal including the instruction signal through a means,
At least some of the unit batteries in the assembled battery are connected in series to the adjacent unit batteries by a connection part that can be physically disconnected,
The assembled battery is configured to be disconnected from an electrical load to which electric power is supplied from the assembled battery in conjunction with the disconnection of the connection portion,
The signal transmitting means shuts off the monitoring units corresponding to the unit batteries connected at the connecting portion when the connecting portion is disconnected, and is connected at the connecting portion. A battery comprising: a transmission path switching unit that switches a transmission path of a signal including the instruction signal in the monitoring unit corresponding to a unit battery from the adjacent monitoring unit to the monitoring control unit. Monitoring device. Comprising switching control means for controlling the operation of the transmission path switching means,
The transmission path switching unit includes a signal transmission unit that transmits a signal including the instruction signal between the monitoring unit corresponding to the unit battery connected by the connection unit and the monitoring control unit, and the connection unit. A first connection opening / closing section for conducting and blocking between the monitoring units corresponding to the unit cells to be connected;
2. The battery monitoring device according to claim 1, wherein the switching control unit shuts off between the monitoring units corresponding to the unit batteries connected by the connection unit when the connection unit is disconnected. 3. . The signal transmission unit is connected by a resistor for suppressing a current flowing between a monitoring unit corresponding to the unit battery connected by the connection unit and the monitoring control unit to a predetermined current value or less, and the connection unit A second connection opening / closing section for conducting and blocking between the monitoring unit corresponding to the unit battery and the monitoring control means,
The switching control means conducts electrical connection between the monitoring unit corresponding to the unit battery connected by the connection portion and the monitoring control means when the connection portion is disconnected. 2. The battery monitoring device according to 2.   The battery monitoring device according to claim 3, wherein the first connection opening / closing part and the second connection opening / closing part are configured by a photorelay. The connecting portion is a battery monitoring device according to any one of claims 1 to 4, characterized in that the service plug can be cut off between the unit cells to the adjacent. The connecting portion is a battery monitoring device according to any one of claims 1 to 4, characterized in that a fuse capable of interrupting between the unit cells to the adjacent.

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