JP5508180B2 - Power storage device, power storage device charge / discharge method, power storage device driving method, and vehicle - Google Patents

Description

The present invention relates to a power storage device, a charge / discharge method for the power storage device, a method for operating the power storage device, and a vehicle including the power storage device .

  In a power storage device that requires a large capacity, such as for an electric vehicle, an assembled battery having a large capacity by connecting a large number of secondary battery cells (unit cells) in series and parallel is used. In such a large-capacity assembled battery, a lithium ion battery is suitable because of its high energy density and charge / discharge efficiency, and it has come to be widely used in recent years with the development of its performance.

  Due to its high energy density and low internal resistance, a lithium ion battery may cause abnormal heat generation and the like if it is left unattended and charging / discharging is continued. For this reason, it is necessary to detect abnormalities reliably and perform safe charge / discharge control.

  Patent Document 1 discloses an abnormality detection device for detecting an abnormality of an assembled battery in an assembled battery in which a plurality of parallel cell blocks in which a plurality of secondary battery cells are connected in parallel are connected in series. In this abnormality detection device, fluctuations in the voltage of each parallel cell block are detected by detecting the voltage at the parallel connection body that connects the secondary battery cells of each parallel cell block, and then the abnormality of each parallel cell block is detected. Is detected.

JP2009-216448

  However, in the configuration of the abnormality detection apparatus as described in Patent Document 1, depending on the type and performance of the secondary battery cells connected in parallel, even if an abnormality occurs in each secondary battery cell or parallel connection body, other healthy There is a possibility that abnormalities cannot be detected due to the characteristics of the secondary battery cells.

(1) an invention according to claim 1, the first switch and one or more unit cells of cell groups connected in series, the battery modules connected in parallel a plurality or series-parallel, first switch controller for selecting the cell group by switching the switch, and a battery controller having a first voltage detector for detecting a voltage of the selected cell group by the switch control unit, is detected by the first voltage detecting unit was based on the voltage, comprising: a diagnostic means for diagnosing abnormal connection anomaly and the battery modules of the battery module, a first voltage detecting unit includes a first voltage detector, a first resistor, the second and a switch, a power storage device according to claim Rukoto have first resistor and a second switch connected in series are connected in parallel with the first voltage detector.
(2) The invention described in claim 2 is the power storage device according to claim 1, wherein the battery control device detects a voltage applied to the first switch of the cell group selected by the switch control unit. The power storage device further includes a second voltage detection unit, and diagnoses an abnormality of the first switch of the cell group based on the voltage detected by the second voltage detection unit.
(3) The invention according to claim 3, in the power storage device according to claim 2, the second voltage detecting unit includes a second voltage detector, and a second resistor connected in series the 3 is a power storage device characterized in that three switches are connected in parallel to the second voltage detector.
(4) The invention according to claim 4 is the power storage device according to any one of claims 1 to 3, wherein the battery control device further includes a plurality of cell controllers, and each cell controller corresponds to a corresponding one. The power storage device is characterized in that the state of charge of each unit cell is equalized by detecting the state of charge of each unit cell included in the cell group to be discharged and discharging the unit cell.
(5) The invention according to claim 5 is the power storage device according to any one of claims 1 to 4, wherein the battery control device selects the cell group by controlling the first switch by the switch control unit. In this power storage device, the state of charge of the cell group is equalized by detecting the state of charge of the cell group and charging the cell group as necessary.
(6) In the power storage device according to any one of claims 4 and 5, the invention described in claim 6 detects a charging state of each unit cell and a battery module connection abnormality, and an abnormal cell group is detected. If detected, the power storage device is characterized in that the first switch of the abnormal cell group is controlled to disconnect the cell group from the battery module.
(7) The invention according to claim 7 uses the power storage device according to any one of claims 1 to 4 to control the first switch to select a cell group, and to select the selected cell A charging / discharging method for a power storage device, characterized in that charging or discharging of a group is performed and the state of charge of the cell group is equalized.
(8) The invention described in claim 8 uses the power storage device according to any one of claims 4 and 5 to detect a charging state of each unit cell and connection abnormality of the battery module, and to detect an abnormal cell. When a group is detected, the first switch of the abnormal cell group is controlled to disconnect the cell group from the battery module, and the battery function is continuously provided by the remaining single battery. This is the driving method.
(9) The invention according to claim 9 includes the power storage device according to any one of claims 1 to 6 and a traveling motor driven by electric power controlled by the power storage device. This is a vehicle that can be electrically driven.

With the battery control device according to the present invention, it is possible to reliably detect abnormality of secondary battery cells or assembled batteries connected in series and parallel, and to ensure the safety and reliability of a power storage device including a plurality of assembled batteries. Can do.
In addition, it is possible to efficiently equalize the state of charge of each secondary battery cell or each assembled battery.
Furthermore, an abnormal secondary battery cell or a cell group in which a plurality of secondary battery cells are connected in series is reliably disconnected from the power storage device, and a degenerate operation with the remaining healthy secondary battery cells or assembled batteries becomes possible.

It is the schematic of the whole circuit which detects the connection abnormality of the conventional assembled battery. It is the schematic of the voltage detection circuit for detecting the connection abnormality of the conventional assembled battery. It is the schematic of the whole circuit of the cell monitor which detects the connection abnormality of an assembled battery by the 1st Embodiment of this invention. It is the schematic of the circuit of the voltage detection part for detecting the connection abnormality of an assembled battery by the 1st Embodiment of this invention. It is the schematic which shows the flow of the method of detecting the connection abnormality of an assembled battery by the 1st Embodiment of this invention. It is the schematic of the whole circuit of the cell monitor which detects the connection abnormality of an assembled battery by the 2nd Embodiment of this invention. (A) The case where only the voltage at the switch of the assembled battery is detected, and (b) the case where the voltage at the part including the bus bar and the voltage detection line, which is the connection path of the switch, is detected. It is the schematic of the battery control apparatus incorporating the cell monitor which detects the connection abnormality of an assembled battery by the 3rd Embodiment of this invention. It is the schematic of the cell controller which controls the cell group used in the 3rd Embodiment of this invention containing a several cell. It is the schematic of the whole motor drive device applicable to an electric vehicle and a hybrid vehicle including the electrical storage apparatus incorporating the battery control apparatus by the 3rd Embodiment of this invention which is the 4th Embodiment of this invention. . It is the schematic of the whole structure of a hybrid vehicle provided with the electrical storage apparatus by the 4th Embodiment of this invention which is the 5th Embodiment of this invention. It is the modification of the cell monitor by the 1st Embodiment of this invention, and is the schematic of the flow of the method of equalizing the charge condition of each single battery contained in a cell group. It is a modification of the 2nd Embodiment of this invention, and is an Example of the cell monitor applied to secondary batteries other than a lithium battery. It is a modification example of the voltage detection part by the 1st and 2nd embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
Here, a plurality of secondary battery cells (single cells) connected in parallel are referred to as a parallel cell group, and a plurality of secondary battery cells connected in series are referred to as a series cell group. In general, a plurality of cell groups connected in series and parallel are referred to as a battery module, and the power storage device has a plurality of battery modules to increase the capacity. In addition, a cell group, a battery module, etc. to which a plurality of single cells are connected are collectively called an assembled battery.

<Description of comparative technology>
First, the comparison technique will be described with reference to FIG.
FIG. 1 is a schematic diagram of a cell monitor 50 that detects a connection abnormality of these batteries in a parallel cell group in which three unit cells BC1 to BC3 are connected in parallel as a simple example. The unit cells BC1 to BC3 are made of power storage elements such as lithium ion batteries, nickel metal hydride batteries, lead batteries, nickel cadmium batteries, and ultracapacitors. The positive electrodes of BC3 of the three batteries BC1 to BC3 are connected by bus bars 21 and 31, and the bus bar 31 is connected to the voltage detector 51 of the cell monitor 50 by a positive voltage detection line SLP. Further, the negative electrodes of BC3 of the three batteries BC1 to BC3 are connected by bus bars 22 and 32, and the bus bar 32 is connected to the voltage detector 51 of the cell monitor 50 by a negative voltage detection line SLN.

  For example, as shown in FIG. 2, the voltage detector 51 includes a resistor 62, a switch 63, and a voltage detector 64. The switch 63 is configured using a semiconductor switch element such as a MOSFET or a bipolar transistor or a mechanical switch element such as a mechanical relay. The switch 63 is ON / OFF controlled from an external controller (not shown), and when it is OFF, the voltage of the parallel cell group is detected.

  Now, assume a case where an abnormality occurs in which any of the bus bars 21, 31, 22, and 32 is disconnected. In this case, since the battery BC3 is connected to at least the voltage detection unit 51 and a normal voltage is always applied, the voltage detector 64 has the same voltage behavior as normal even when the switch 63 is turned ON / OFF. Observed, the connection abnormality of any of the bus bars 21, 31, 22, 32 cannot be detected. Further, it is naturally impossible to detect an abnormality in the single cells BC1 and BC2.

<First Embodiment>
FIG. 3 is a schematic diagram for explaining the first embodiment of the present invention. Switches SW1, SW2, and SW3 are connected in series to the three single cells BC1, BC2, and BC3, respectively. Each unit cell and the switch are further connected in parallel by bus bars 21, 31, 22 and 32.

  The cell monitor 50 is a battery monitoring device that monitors whether or not the connections of the single cells BC1 to BC3 connected in parallel are abnormal, and includes a voltage detection unit 51 and a switch control unit 52 that controls the switches SW1 to SW3. Prepare. The bus bar 31 is connected to the voltage detection unit 51 via the positive voltage detection line SLP, and the bus bar 32 is connected to the voltage detection unit 51 via the negative voltage detection line SLN.

  As the switches SW1, SW2, and SW3, semiconductor switch elements such as MOSFETs and bipolar transistors or mechanical switch elements such as mechanical relays are used. When secondary battery cells that can be charged and discharged are used as the single cells BC1, BC2, and BC3, bidirectional current flows through the switches SW1, SW2, and SW3 due to charging and discharging. And configured to be compatible with bidirectional current. Cv is a noise countermeasure capacitor.

  The cell monitor 50 includes a switch control unit 52 and a voltage detection unit 51. Although not shown in FIG. 3, the cell monitor 50 receives an instruction from a host control device and controls the switch controller 52 and the voltage detector 51.

FIG. 4 shows an outline of a circuit of the voltage detector 51 according to the present invention. Compared with the voltage detection unit of the comparative example shown in FIG. 2, the voltage detection unit according to the present invention has two resistors 61 </ b> A and 61 </ b> B added, and the voltage detector 64 is a circuit in which the resistor 62 and the switch 63 are connected in series. Connected in parallel. FIG. 4 corresponds to the case where the switch SW3 is turned on and the switches SW1 and SW2 are turned off as shown in FIG. 3, and these switches are omitted.
The switch 63 includes a semiconductor switch element such as a MOSFET or a bipolar transistor, or a mechanical switch element such as a mechanical relay.

<Principle of path abnormality detection>
Here, the principle of detecting an abnormality in the wiring path of the secondary battery cell using the voltage detection unit 51 of the present invention shown in FIG. 4 will be described.

In FIG. 4, when the switch 63 is turned OFF, the voltage V measured by the voltage detector 64 becomes the terminal voltage _VBC3 itself of the unit cell BC3.
When the switch 63 is turned ON, a closed loop is formed with the cell BC3 via the voltage detection line SLP, the resistors 61A and 62, the switch 63 and the resistor 61B, and the voltage detection line SLN. At this time, the voltage detection unit 51 detects a voltage obtained by subtracting a voltage drop in the voltage detection line SLP, the resistors 61A and 61B, and the voltage detection line SLN from the voltage of the battery BC3.
That is, the internal resistance value of the unit cell BC3 is r _BC3 , the resistance of the voltage detection line SLP including the connection resistance at the connection point CBP and the connection resistance at the connection point CMP is r _SLP , and the connection resistance at the connection point CBN The resistance value of the voltage detection line SLN including the connection resistance at the connection point CMN is defined as r _SLN, and the resistance values of the resistors 61A, 61B, and 62 are respectively included in the resistances r _61A and r _61B including the wiring resistances up to these connection points. , R _62, and the resistance value of the switch 63 including the wiring resistance up to this connection point is r ₆₃ , if the elements constituting the above closed loop are firmly connected, the voltage detector 64 uses the following formula ( The voltage V shown in 1) is detected.
_{V = V BC3 × (r 62} + r 63) / (r BC3 + r SLP + r SLN + r 61A + r 61B + r 62 + r 63)
. . . (1)
The connection resistances at the path-like connection points CVP, CSR, CVN of the resistors 61A, 61B, 62 and the switch 63 are the resistances in the wiring inside the voltage detector 51, and the resistance values r _61A , r _61B , It is sufficient to transfer the values to r ₆₂ and r ₆₃ as appropriate, and these resistance values do not substantially affect the description here.

Here, if any of the bus bars 31 and 32, the voltage detection line SLP, the resistor 61A and the resistor 61B, and the voltage detection line SLN is insufficiently connected, the resistance (or contact resistance) there increases. When the switch 63 is turned on, the division denominator on the right side of the above equation (1) becomes large, so that the voltage detector 64 detects a value smaller than the voltage V. Further somewhere above the closed loop, since if the connection is disconnected, or if the disconnection is taking place the terminal voltage V _BC3 of BC3 unit cells is not applied, the voltage detected by the voltage detector 64 becomes 0V . As described above, the connection abnormality of the closed loop circuit can be diagnosed based on the voltage detection value by the voltage detector 64 when the switch 63 is turned ON / OFF.

<Detection of path abnormality in parallel cell group>
Here, a method for diagnosing a path abnormality in a parallel cell group will be described using the principle described above for detecting a wiring path abnormality.

  In FIG. 3, the switch SW3 is ON, and the others are OFF. For this reason, when any of the bus bars 21, 31, 22, 32 and the voltage detection lines SLP, SLN is disconnected, the voltage application from the unit cell BC1 is interrupted, so that the voltage detection unit 51 can correctly detect the abnormality. It becomes.

FIG. 5 is a diagram illustrating an example of a diagnosis flow. This diagnosis flow is executed according to a program installed in a host CPU (not shown) of the cell monitor 50. First, in step S001, the switch SW3 is turned on, SW1 and SW2 are turned off, and the path of the unit cell BC3, the voltage detection lines SLP and SLN, and the voltage detection unit 51 is configured. Next, to measure the voltage _{V 3} when only _BC3 voltage _V of BC3 unit cell by the voltage detector 51 is applied in step S002.

The value of the step S003 _{V 3} determines whether the normal voltage range of BC3 unit cells. If V ₃ is not a normal range, the process proceeds to step S013, where the connection abnormality determination of the voltage detection line 114A or 114B, the flow ends. If V ₃ is within the normal range, the process proceeds to step S004, the voltage detecting lines SLP or SLN is judged to be normal.

In step S005, the switch SW2 is turned on, SW3, SW1 are turned off, and the path of the unit cell BC2, the bus bars 31, 32, the voltage detection lines SLP, SLN, and the voltage detection unit 51 is configured. Then, to measure the voltage _{V 2} when only the voltage _{V BC2} of the cell BC2 by the voltage detecting unit is applied in step S006.

Value of the step S007 in _{V 2} determines whether the normal voltage range of the battery 111B. If V ₂ is not a normal range, the process proceeds to step S014, where it determines that the abnormal connection bus bar 31 or 32, the flow is terminated. If V ₂ is within the normal range to determine the bus bar 31 or 32 from the normal at step S008.

In step S009, the switch SW1 is turned ON, SW2 and SW3 are turned OFF, and the unit cell BC1, bus bars 21, 22, 31, 32, voltage detection lines SLP, SLN, and the voltage detection unit 51 path are configured. Then, to measure the voltages _{V 1} when applying only a single cell BC1 voltage _{V BC1} by the voltage detecting unit 51 in step S010.

Step value of _{V 1} at S011 it is determined whether the normal voltage range of the cell BC1. If V ₁ is not the normal range, the process proceeds to step S015, where it determines that the abnormal connection busbar 21 or 22, the flow is terminated. If V ₁ is within the normal range busbars 21 or 22 at step S012 to end the flow is judged to be normal.

  In this way, according to the embodiment of the present invention, the switches SW1, SW2, and SW3 are used to identify where abnormality is occurring in the unit cell, bus bar, and voltage detection line that are to be diagnosed. Can be reliably detected.

  Detected abnormalities are signaled to a host control device, appropriate safety measures are taken, and necessary information is also presented to the driver of an electric vehicle or the like equipped with a cell group as described above. Therefore, it becomes possible to ensure the safety and reliability of the electric vehicle.

  In a power storage device used in an electric vehicle or the like, a plurality of parallel cell groups as shown in FIG. 3 or a plurality of series cell groups are connected in series and parallel as described later. When an abnormality is detected in these secondary battery cells (single cells) or cell group, the cell monitor 50 can perform a degenerate operation by controlling a switch connected to the abnormal single cell. The abnormal single cell or the parallel cell group or series cell group including the abnormal single cell is disconnected, and the battery function is continued to be provided by the remaining healthy single cells, parallel cell group or series cell group. Thereby, it becomes possible to continue the operation of the electric vehicle while degenerating without stopping the function of the battery system.

  The diagnosis according to the present invention is preferably performed at the time of starting the power storage system (vehicle key-on) or after finishing (vehicle key-off). Turning off the switches SW1, SW2, and SW3 interrupts the transfer of electric power of the unit cell, but diagnosis can be performed during operation as long as the electric power required by the electric vehicle can be satisfied. I can do it.

<Second Embodiment>
FIG. 6A is a diagram for explaining a second embodiment of the present invention. Compared to FIG. 3, the single cells BC1 to BC3 are connected in series with the switches SW1 to SW3, respectively, and each set of single cells and switches connected in series is connected in parallel to the switch diagnosis unit 65 and the switch selection unit 60. Connected through.

The switch selection unit 60 includes a multiplexer or the like, and selects one connection point between each of the single cells BC1, BC2, and BC3 and the switches SW1, SW2, and SW3, and connects the switch diagnosis unit 65.
In FIG. 6A, the switch selection unit 60 is connected to the lower side (unit cell side) of the switch of each unit cell, and a common connection line is connected to the upper side (bus bar side) of these switches. Although connected from the unit 65, the upper and lower connection lines of these switches may be interchanged.

The switch diagnosis unit 65 has the same circuit as the voltage detection unit 51 described above, measures the voltage between the terminals of the switch selected by the switch selection unit 60 from the switches SW1, SW2, and SW3, and diagnoses the conduction state thereof. To do.
By diagnosing the conduction state of the switches SW1, SW2, and SW3, it is confirmed that the cell, bus bar, and voltage detection line to be diagnosed are reliably selected by the switches SW1, SW2, and SW3. Therefore, it is possible to reliably detect these abnormalities and to ensure safety and reliability.

  That is, as described above, the voltage detection unit 51 that detects an abnormality in the entire connection path of the selected unit cell, and in addition, the voltage detection unit 51 that detects the conduction state of the switch of the selected unit cell. By providing the switch diagnosis unit 65 having the same function as the above, it is possible to confirm that the cell to be diagnosed is reliably selected, and to reliably detect an abnormality in the connection path of this cell. it can.

  Note that, as described in the first embodiment of the present invention, when the connection of the bus bars other than the switch and the voltage detection line SLP is also confirmed at the same time, they may be connected as shown in FIG.

<Third Embodiment>
FIG. 7 is a diagram for explaining a third embodiment of the present invention. Compared to FIG. 6, four unit cells BC11-14 and switch SW1 are connected in series, four unit cells BC21-24 and switch SW2 are connected in series, four unit cells BC31-34 and switch SW3. Are connected in series to form series cell groups 20A1, 20A2, and 20A3, respectively. These three series cell groups are connected in parallel to form a battery module block 20A. Each of the three series cell groups 20A1, 20A2, and 20A3 is controlled by cell controllers IC1, IC2, and IC3, which monitor the states of the single cells included in these cell groups and perform charge / discharge, etc., as necessary. Yes. This configuration is suitable for a secondary battery having an organic solvent electrolyte such as a lithium ion battery that needs to monitor the state of each battery individually.
In FIG. 7, the noise countermeasure capacitors described in FIGS. 4 and 6 are omitted.

In an actual electric vehicle power storage device, a plurality of such battery module blocks made up of series cells connected in series and parallel are connected in series and parallel. The cell monitor 50A shown in FIG. 7 has the same configuration and function as the cell monitor 50 described in the first embodiment of the present invention, and in the third embodiment shown in FIG. Detect connection errors.
In addition, hereinafter, a switch in which a switch is connected in series to a series cell group is also referred to as a series cell group unless otherwise misunderstood.

  Cell controller ICs 1 to 3 that control each cell group include a communication system 602 and a 1-bit communication system 604, respectively. As will be described later, the cell controllers IC1 to IC3 communicate with a host controller (referred to as the microcomputer 30) through these communication systems to control and diagnose the charge state of each secondary battery cell of the battery module block. Although not shown in FIG. 7, the 1-bit communication system 604 is further connected to another battery module block connected in series to the battery module block 20A.

  Here, with reference to FIG. 8, the configuration of the cell controller IC and the method of controlling the state of charge of each unit cell will be described.

<Configuration of cell controller IC>
FIG. 8 is a diagram showing an outline of an internal block of the cell controller IC, which is a battery control IC, and shows an example of the cell controller IC1 to which the four battery cells BC11 to BC14 of the cell group 20A1 are connected. Although explanation is omitted, other ICs have the same configuration. As described above, the number of battery cells included in each cell group is not limited to four, and may be six or more. The cell controller IC is designed to accommodate the number of battery cells included in the cell group. For example, the cell controller IC already has six balancing switches so that it can handle six battery cells, but if the number of battery cells included in the cell group is four, the six balancing switches Only 4 of them are used.

  The cell controller IC1 includes a multiplexer 120 as a battery state detection circuit, an analog-digital converter 122A, an IC control circuit 123, a diagnostic circuit 130, transmission input circuits 138 and 142, transmission output circuits 140 and 143, a start circuit 254, a timer circuit. 150, a control signal detection circuit 160, a differential amplifier 262, and an OR circuit 288 are provided.

  The terminal voltages of the battery cells BC11 to BC14 are input to the multiplexer 120 via the voltage detection lines SL1 to SL5, the voltage input terminals CV1 to CV4, and the GND terminal. The multiplexer 120 selects any one of the voltage input terminals CV 1 to CV 4 and the GND terminal, and inputs the inter-terminal voltage to the differential amplifier 262. The output of the differential amplifier 262 is converted into a digital value by the analog-digital converter 122A. The inter-terminal voltage converted into a digital value is sent to the IC control circuit 123 and held in the internal data holding circuit 125. The terminal voltages of the battery cells BC1 to BC4 inputted to the voltage input terminals CV1 to CV4 and the GND terminal are biased with a potential based on the terminal voltage of the battery cells connected in series with respect to the GND potential of the cell controller IC1. Yes. The influence of the bias potential is removed by the differential amplifier 262, and an analog value based on the terminal voltages of the battery cells BC1 to BC4 is input to the analog-digital converter 122A.

  The IC control circuit 123 has an arithmetic function, a data holding circuit 125, a timing control circuit 126 that periodically performs voltage measurement and state diagnosis, and a diagnosis flag holding circuit 128 in which a diagnosis flag from the diagnosis circuit 130 is set. And have. The IC control circuit 123 decodes the content of the communication command input from the transmission input circuit 138 and performs processing according to the content. Examples of commands include a command for requesting a measured value of the voltage between terminals of each battery cell, a command for requesting a discharge operation for adjusting the charge state of each battery cell, and a command for starting the operation of the cell controller IC. (Wake UP), a command to stop the operation (sleep), a command to request address setting, and the like.

  The diagnosis circuit 130 performs various diagnoses, for example, overcharge diagnosis and overdischarge diagnosis, based on the measurement value from the IC control circuit 123. The data holding circuit 125 is configured by, for example, a register circuit, stores the detected voltage between the terminals of the battery cells BC11 to BC14 in association with the battery cells BC11 to BC14, and stores other detection values. It is held so that it can be read out at a predetermined address.

  At least two types of power supply voltages VCC and VDD are used in the internal circuit of the cell controller IC1. In the example illustrated in FIG. 8, the voltage VCC is a voltage of a battery module block including battery cell groups 20A1, 20A2, and 20A3 connected in parallel, and the voltage VDD is generated by the constant voltage power supply 134. The multiplexer 120 and the transmission input circuits 138 and 142 for signal transmission operate at a high voltage VCC. The analog-digital converter 122A, the IC control circuit 123, the diagnostic circuit 130, and the transmission output circuits 140 and 143 for signal transmission operate at a low voltage VDD.

  The signal received at the reception terminal LIN1 of the cell controller IC1 is input to the transmission input circuit 138, and the signal received at the reception terminal FFI is input to the transmission input circuit 142. The transmission input circuit 142 has a circuit configuration similar to that of the transmission input circuit 138. The transmission input circuit 138 includes a circuit 231 that receives a signal from another adjacent cell controller IC and a circuit 234 that receives a signal from the photocoupler PH.

  As shown in FIG. 8, in the case of the highest cell controller IC1, a signal from the photocoupler PH is inputted to the reception terminal LIN1, and in the case of the cell controller IC2, a signal from the adjacent IC1 is inputted to the reception terminal LIN1. Is input. Therefore, which of the circuits 231 and 234 is used is selected by the switch 233 based on the control signal applied to the control terminal CT in FIG. The control signal applied to the control terminal CT is input to the control signal detection circuit 160, and the switch 233 performs a switching operation according to a command from the control signal detection circuit 160.

  That is, when a signal from the host controller (microcomputer 30) is input to the cell controller IC at the highest transmission direction in the cell controller IC, that is, the reception terminal LIN1 of the cell controller IC1, the switch 233 is on the lower side. The contact is closed, and the output signal of the circuit 234 is output from the transmission input circuit 138. On the other hand, when the signal from the adjacent cell controller IC is input to the receiving terminal LIN1 of the lower cell controller IC which is not the highest in the transmission direction, the upper contact of the switch 233 is closed and the output signal of the circuit 232 is transmitted. Output from the input circuit 138. In the case of the cell controller IC2, since the signal from the adjacent IC1 is input to the transmission input circuit 138, the upper contact of the switch 233 is closed. Since the peak value of the output waveform is different between the output from the host controller (microcomputer 30) and the output from the transmission terminal LIN2 of the adjacent cell controller IC, the determination threshold value is different. For this reason, the switch 233 of the circuit 138 is switched based on the control signal of the control terminal TC. The communication system 604 has the same configuration.

  The communication command received at the reception terminal LIN1 is input to the IC control circuit 123 through the transmission input circuit 138. The IC control circuit 123 outputs data and commands corresponding to the received communication command to the transmission output circuit 140. Those data and commands are transmitted from the transmission terminal LIN2 via the transmission output circuit 140. The transmission output circuit 143 has the same configuration as the transmission output circuit 140.

  The signal received from the terminal FFI is used to transmit an abnormal state (overcharge signal). When a signal indicating abnormality is received from the terminal FFI, the signal is input to the transmission output circuit 143 via the transmission input circuit 142 and the OR circuit 288, and is output from the transmission output circuit 143 via the terminal FFO. When an abnormality is detected by the diagnostic circuit 130, a signal indicating the abnormality is input from the diagnostic flag holding circuit 128 to the transmission output circuit 143 via the OR circuit 288 regardless of the content received at the terminal FFI, and the terminal is transmitted from the transmission output circuit 143 to the terminal. Output via FFO.

  When the activation circuit 147 receives the signal transmitted from the adjacent cell controller IC or the photocoupler PH, the timer circuit 150 operates and supplies the voltage VCC to the constant voltage power supply 134. By this operation, the constant voltage power supply 134 is in an operating state and outputs a constant voltage VDD. When the constant voltage VDD is output from the constant voltage power supply 134, the cell controller IC2 rises from the sleep state and enters an operation state.

  The voltage input terminals CV1 to CV4 of the cell controller IC1 are terminals for measuring the cell voltage of the battery cell. Voltage detection lines SL1 to SL4 are connected to the voltage input terminals CV1 to CV4, respectively, and resistances RCV for terminal protection and discharge current limitation for capacity adjustment are provided on the respective voltage detection lines. The voltage detection lines SL1 to SL4 connect the voltage input terminals CV1 to CV4 and the positive electrode or the negative electrode of each battery cell BC. The voltage detection line SL5 is connected from the negative electrode of the battery cell BC4 to the GND terminal. For example, when measuring the cell voltage of the battery cell BC11, the voltage between the voltage input terminals CV1 and CV2 is measured. Moreover, when measuring the cell voltage of battery cell BC14, the voltage between voltage input terminal CV4-GND terminal is measured. Capacitors Cv and Cin are provided between the voltage detection lines as noise countermeasures. As will be described later, the battery cell side portion and the cell controller IC side portion of these voltage detection lines are connected by a connector that connects the battery module and the battery control device.

  In order to make the best use of the performance of the battery module 20A of FIG. 7, it is necessary to equalize the cell voltages of a total of 12 battery cells. For example, when there is a large variation in cell voltage, it is necessary to stop the regenerative operation when the highest battery cell reaches the upper limit voltage during regenerative charging. In this case, although the cell voltage of the other battery cells has not reached the upper limit, the regenerative operation is stopped and energy is consumed as a brake. In order to prevent this, each cell controller IC performs discharge for adjusting the capacity of the battery cell in response to a command from the microcomputer 30.

  As shown in FIG. 8, each cell controller IC includes balancing switches BS1 to BS4 for adjusting cell capacity between the terminals of CV1-BR1, BR2-CV3, CV3-BR3, and BR4-GND. For example, when discharging the battery cell BC1, the balancing switch BS1 is turned on. Then, a balancing current flows through the path of the positive electrode of the battery cell CV1, the resistor RCV, the CV1 terminal, the balancing switch BS1, the BR1 terminal, the resistor RB, and the negative electrode of the battery cell CV1. Note that RB or RBB is a resistor for balancing, and BR1 to BR4 are terminals for performing this balancing.

  Thus, balancing switches BS1 to BS4 for adjusting the charge amounts of the battery cells BC11 to BC14 are provided in the cell controller IC. In an actual cell controller IC, PMOS switches are used for the balancing switches BS1 and BS3, and NMOS switches are used for the balancing switches BS2 and BS4.

  Opening and closing of these balancing switches BS1 to BS4 is controlled by a discharge control circuit 132. Based on a command from the microcomputer 30, a command signal for turning on the balancing switch corresponding to the battery cell to be discharged is sent from the IC control circuit 123 to the discharge control circuit 132. The IC control circuit 123 receives a discharge time command corresponding to each of the battery cells BC1 to BC4 from the microcomputer 30 through communication, and executes the discharge operation.

  As described above, the communication systems 602 and 604 are provided between the cell controller IC1 and the cell controller IC2. A communication command from the microcomputer 30 is input to the communication system 602 through the photocoupler PH, and is received by the reception terminal LIN1 of the cell controller IC1 through the communication system 602. Data and commands corresponding to the communication commands are transmitted from the transmission terminal LIN2 of the cell controller IC1. Thus, reception and transmission are performed in sequence between the cell controller ICs, and the transmission signal is transmitted from the transmission terminal LIN2 of the cell controller IC2 and received at the reception terminal of the microcomputer 30 via the photocoupler PH. The cell controllers IC1 and IC2 perform measurement data such as cell voltage to the microcomputer 30 and a balancing operation according to the received communication command. Furthermore, each cell controller IC1 and IC2 detects cell overcharge based on the measured cell voltage. The detection result (abnormal signal) is transmitted to the microcomputer 30 via the signal system 604.

  In the third embodiment, as described above, each unit cell is constantly monitored by the corresponding cell controller IC1, IC2, IC3, and the state of charge of each unit cell is equalized. In addition, the cell controller transmits information on the state of charge of each unit cell to the host control device (microcomputer 30), so that the connection path diagnosis described in the first embodiment and the second embodiment can be performed as necessary. Done. Since it is confirmed that the serial cell group, the bus bar, and the voltage detection line are surely selected, and these diagnoses can be reliably performed, it is possible to ensure the safety and reliability of the power storage device. .

<Fourth Embodiment>
FIG. 9 explains the fourth embodiment of the battery control device and the power storage device of the present invention, and outlines the entire motor drive device applicable to an electric vehicle and a hybrid vehicle using the fourth embodiment. FIG. Two battery module blocks (20A and 20B) shown in FIG. 7 are connected in series.

  The drive device shown in FIG. 9 includes a battery module 20, a battery control device 100 that monitors the battery module 20, a power storage device 11 that includes the battery control device 100 and the battery module 20, and three-phase AC power from the DC power from the battery module 20. Inverter device 9 for converting into a motor and motor generator 7 for driving the vehicle. The motor 230 is driven by the three-phase AC power from the inverter device 9. The inverter device 9 and the battery control device 100 are connected by CAN communication, and the inverter device 9 functions as a host controller for the battery control device 100. The inverter device 9 operates based on command information from a higher-level control device 10 (described later).

  The inverter device 9 includes a power module 226, an MCU 222 that controls the inverter device, and a driver circuit 224 for driving the power module 226. The power module 226 converts the DC power supplied from the battery module 20 into three-phase AC power for driving the motor generator 7 as a motor. Although not shown, a large-capacity smoothing capacitor of about 700 μF to about 2000 μF is provided between the high voltage lines HV + and HV− connected to the power module 226. The smoothing capacitor serves to reduce voltage noise applied to the integrated circuit provided in the battery control device 100.

  When the inverter device 9 starts operating, the charge of the smoothing capacitor is substantially zero, and when the relay RL is closed, a large initial current flows into the smoothing capacitor. The relay RL may be fused and damaged due to the large current. In order to solve this problem, the MCU 222 charges the smoothing capacitor by changing the precharge relay RLP from the open state to the closed state at the start of driving of the motor generator 7 according to a command from the higher-level control device 10, and then Then, the relay RL is changed from the open state to the closed state, and the supply of power from the battery module 20 to the inverter device 9 is started. When charging the smoothing capacitor, charging is performed while limiting the maximum current via the resistor RP. By performing such an operation, it is possible to protect the relay circuit, reduce the maximum current flowing through the battery cell and the inverter device 9 to a predetermined value or less, and maintain high safety.

  The inverter device 9 controls the phase of the AC power generated by the power module 226 with respect to the rotor of the motor generator 7, and operates the motor generator 7 as a generator during vehicle braking. That is, regenerative braking control is performed, and the battery module 20 is charged by regenerating the power generated by the generator operation to the battery module 20. When the state of charge of the battery module 20 is lower than the reference state, the inverter device 9 operates using the motor generator 7 as a generator. The three-phase AC power generated by the motor generator 7 is converted into DC power by the power module 226 and supplied to the battery module 20. As a result, the battery module unit 20 is charged.

  On the other hand, when the motor generator 7 is operated as a motor, the MCU 222 controls the driver circuit 224 so as to generate a rotating magnetic field in the forward direction with respect to the rotation of the rotor of the motor generator 7 in accordance with a command from the control device 10. Then, the switching operation of the power module 226 is controlled. In this case, DC power is supplied from the battery module 20 to the power module 226. When the battery module 20 is charged by regenerative braking control, the MCU 222 controls the driver circuit 224 so as to generate a rotating magnetic field in a delay direction with respect to the rotation of the rotor of the motor generator 7, and the power module The switching operation of H.226 is controlled. In this case, electric power is supplied from the motor generator 7 to the power module 226, and DC power of the power module 226 is supplied to the battery module 20. As a result, the motor generator 7 acts as a generator.

  The power module 226 of the inverter device 9 conducts conduction and interruption at high speed and performs power conversion between DC power and AC power. At this time, since a large current is interrupted at a high speed, a large voltage fluctuation occurs due to the inductance of the DC circuit. In order to suppress this voltage fluctuation, the above-described large-capacity smoothing capacitor is provided.

  The battery module 20 is composed of, for example, two battery module blocks 20A and 20B connected in series here. Each of the battery module blocks 20A and 20B includes a plurality of cell groups in which a plurality of battery cells are connected in series. The battery module block 20A and the battery module block 20B are connected in series via a service disconnect SD-SW for maintenance / inspection in which a switch and a fuse are connected in series. When the service disconnect SD-SW is opened, the direct circuit of the electric circuit is cut off, and even if a connection circuit is made at one place between the battery module blocks 20A and 20B and the vehicle, current will not flow. Absent. With such a configuration, high safety can be maintained. Even if an operator touches between HV + and HV− during inspection, it is safe because a high voltage is not applied to the human body.

  A high voltage line HV + between the battery module 20 and the inverter device 9 is provided with a battery disconnect unit BDU including a relay RL, a resistor RP, and a precharge relay RLP. A series circuit of the resistor RP and the precharge relay RLP is connected in parallel with the relay RL.

The battery control device 100 mainly performs measurement of each cell voltage, measurement of total voltage, measurement of current, cell temperature and cell capacity adjustment, and the like. Therefore, a plurality of battery control ICs (integrated circuits) are provided as cell controllers. A plurality of battery cells provided in each battery module block 20A, 20B are divided into a plurality of cell groups (assembled batteries), and a cell controller that controls the battery cells included in each cell group is provided for each cell group. One by one.
For simplicity, it is assumed in the following description that each cell group is composed of four battery cells. Each battery module block 20A, 20B is assumed to be composed of two cell groups (20A1, 20A2, 20A3 and 20B1, 20B2, 20B3).

  Referring also to FIG. 8, the cell controllers IC1 to IC6 that control each cell group include a communication system 602 and a 1-bit communication system 604, respectively. In the communication system 602 for reading cell voltage values and transmitting various commands, serial communication is performed with the microcomputer 30 that controls the battery module 20 in a daisy chain manner via an insulating element (for example, photocoupler) PH. The 1-bit communication system 604 transmits an abnormal signal when cell overcharge is detected. In the example shown in FIG. 9, the communication system 602 includes an upper communication path for the cell controllers IC1, IC2, and IC3 of the battery module block 20A and a lower communication path for the cell controllers IC4, IC5, and IC6 of the battery module block 20B. It is divided.

  Each cell controller IC performs an abnormality diagnosis and transmits an abnormality signal from the transmission terminal FFO when it determines that it is abnormal or when it receives an abnormality signal from the host cell controller IC at the reception terminal FFI. On the other hand, when the abnormal signal already received at the receiving terminal FFI disappears or when the abnormality judgment of itself becomes normal judgment, the abnormal signal transmitted from the transmission terminal FFO disappears. This abnormal signal is a 1-bit signal in this embodiment.

  The microcomputer 30 does not transmit an abnormal signal to the cell controller IC, but in order to diagnose that the 1-bit communication system 604 that is the transmission path of the abnormal signal operates correctly, a test signal that is a pseudo abnormal signal is transmitted to the 1-bit communication system 604. To send. Receiving this test signal, the cell controller IC1 sends an abnormal signal to the communication system 604, and the abnormal signal is received by the cell controller IC2. The abnormal signal is transmitted from the cell controller IC2 to the cell controllers IC3, IC4, IC5, and IC6 in this order, and finally returned from the cell controller IC6 to the microcomputer 30. If the communication system 604 is operating normally, the pseudo abnormal signal transmitted from the microcomputer 30 returns to the microcomputer 30 via the communication system 604. Thus, the microcomputer 30 can send and receive the pseudo-abnormal signal to diagnose the communication system 604, and the reliability of the system is improved.

  A current sensor Si such as a Hall element is installed in the battery disconnect unit BDU, and the output of the current sensor Si is input to the microcomputer 30. Signals related to the total voltage and temperature of the battery module 20 are also input to the microcomputer 30 and are measured by an AD converter (ADC) of the microcomputer 30. The temperature sensors are provided at a plurality of locations in the battery module blocks 20A and 20B.

  As described above, according to the present invention, it is possible to connect a plurality of cell controller ICs in series, in parallel, or in series and parallel, and to connect the plurality of cell controller ICs and the host control device by communication. Thereby, it is possible to easily construct a power storage device having a larger scale, higher safety, and higher reliability. Further, when an abnormality is detected in the battery or the series cell group of the battery, the cell monitor 50 controls the switch connected to the abnormal battery or the abnormal series cell group, disconnects the abnormal battery or the abnormal series cell group, and the remaining It is possible to provide a healthy each battery or each series cell group battery function. Thereby, it becomes possible to continue to provide the function while degenerating without stopping the function of the battery system such as charging and discharging.

<Fifth Embodiment>
FIG. 10 is a diagram for explaining a fifth embodiment of the present invention. This is an example in which the power storage device of the present invention is applied to a hybrid vehicle. In addition, the configuration of the embodiment of the present invention including the fifth embodiment can be applied to a railway vehicle such as a hybrid train. The battery control device and the power storage device according to the present invention can also be applied to an electric vehicle.

<Schematic configuration of hybrid vehicle drive system>
In the drive system of the hybrid vehicle 1 shown in FIG. 10, the axle 3 mechanically connected to the drive wheel 2 is connected to the differential gear 4, and the input shaft of the differential gear 4 is connected to the transmission 5. And it is an input of the transmission 5 through the driving force switching device 8 which switches the driving force of the engine 6 which is an internal combustion engine, and the motor generator 7 as a drive source.

  In FIG. 10, a so-called parallel hybrid system in which an engine 6 and a motor generator 7 are arranged in parallel as a drive source of the drive wheels 2. In the hybrid vehicle drive system, the energy of the motor generator 7 is used as the drive source of the drive wheels 2, and the energy of the engine 6 charges the drive source of the motor generator 7, that is, the capacitor. There is a hybrid system, and the present invention can employ both of these systems or a combined system.

  A power storage device 11 as a power supply device is electrically connected to the motor generator 7 via an inverter device 9. The inverter device 9 is controlled by the control device 10.

  When the motor generator 7 is operated as a motor, the inverter device 9 functions as a DC-AC conversion circuit that converts DC power output from the power storage device 11 into three-phase AC power. When the motor generator 7 is operated as a generator during regenerative braking, the inverter device 9 functions as an AC-DC conversion circuit that converts the three-phase AC power output from the motor generator 7 into DC power. . The positive and negative terminals of the battery module of the power storage device 11 are electrically connected to the DC side of the inverter device 9. On the AC side of the inverter device 9, there are three series circuits composed of two switching semiconductor elements, and three phase windings of the armature winding of the motor generator 4 are in the middle of the two switching semiconductor elements of the series circuit. It is designed to be electrically connected.

  The motor generator 7 functions as a prime mover for driving the drive wheels 5, and includes an armature (stator) and a field (rotor) disposed opposite to the armature and rotatably held. This is a permanent magnet field type three-phase AC synchronous rotating electric machine using the magnetic flux of the permanent magnet as a field. The motor generator 7 drives the drive wheels 5 based on the magnetic action of a rotating magnetic field formed by three-phase AC power supplied to the armature winding and rotating at a synchronous speed, and the magnetic flux of the permanent magnet. Generate the rotational power necessary for

  When the motor generator 7 is driven as a motor, the armature receives a supply of three-phase AC power controlled by the inverter device 9 and generates a rotating magnetic field. On the other hand, when the motor generator 9 is driven as a generator, the armature becomes a part that generates three-phase AC power by interlinking of magnetic flux, and an armature core (stator core) that is a magnetic body and an armature core. And a three-phase armature winding (stator winding). The field is a part that generates a field magnetic flux when the motor generator 7 is driven as an electric motor or a generator. A field core (rotor core) that is a magnetic body and a permanent that is attached to the field core. And a magnet.

  As the motor generator 7, based on the magnetic action of the rotating magnetic field that is formed by the three-phase AC power supplied to the armature winding and rotates at the synchronous speed, and the magnetic flux generated by the excitation of the winding, the rotating power A winding field type three-phase AC synchronous rotating electric machine or a three-phase AC induction rotating electric machine that generates In the case of a wound field type three-phase AC synchronous rotating electric machine, the configuration of the armature is basically the same as that of a permanent magnet field type three-phase AC synchronous rotating electric machine. On the other hand, the configuration of the field is different, and a field winding (rotor winding) is wound around a field iron core that is a magnetic material. In a wound field type three-phase AC synchronous rotating electric machine, a permanent magnet may be attached to a field core around which a field winding is wound to suppress leakage of magnetic flux due to the winding. The field winding generates a magnetic flux when excited by receiving a field current from an external power source.

  The motor generator 7 is mechanically connected to the axle 3 of the drive wheel 2 via a driving force switching device 8, a transmission 5, and a differential gear 4. The transmission 5 changes the rotational power output from the motor generator 7 and transmits it to the differential gear 4. The differential gear 4 transmits the rotational power output from the transmission 5 to the left and right axles 3. The driving force switching device 8 is switched by a host control device (not shown) such as engine control or traveling control, and is accelerated by engine control, engine starting by the motor generator 7 from idle stop, and regenerative brake coordination in brake control. It is made to operate as an electric motor or a generator by switching.

  The power storage device 11 charges the electric power generated when the motor generator 7 is regenerated as its own driving power, and when the motor generator 7 is driven as a generator, the driving on-vehicle device that discharges the electric power necessary for this driving. It is a power supply. For example, it is a battery system composed of several tens of lithium ion batteries so as to have a rated voltage of 100 V or more. The detailed configuration of the power storage device 11 will be described later.

  The power storage device 11 includes, in addition to the motor generator 7, an electric actuator that supplies power to a vehicle-mounted auxiliary device (for example, a power steering device, an air brake), a rated voltage lower than that of the power storage device 11, and an in-vehicle electrical component (for example, a light , Audio, on-vehicle electronic control device) is electrically connected via a DC / DC converter. The DC / DC converter is a step-up / step-down device that steps down the output voltage of the power storage device 11 and supplies it to an electric actuator or a low-voltage battery, or boosts the output voltage of the low-voltage battery and supplies it to the power storage device 11 or the like. . A lead battery with a rated voltage of 12V is used as the low voltage battery. As the low voltage battery, a lithium ion battery or a nickel metal hydride battery having the same rated voltage may be used.

  When the hybrid vehicle 1 is powered (starting, acceleration, normal traveling, etc.), when a positive torque command is given to the control device 10 and the operation of the inverter device 9 is controlled, the DC power stored in the power storage device 11 is converted into an inverter. It is converted into three-phase AC power by the device 9 and supplied to the motor generator 7. As a result, the motor generator 7 is driven to generate rotational power. The generated rotational power is transmitted to the axle 3 via the driving force switching device 8, the transmission 5, and the differential gear 4 to drive the driving wheels 2.

  During regeneration (deceleration, braking, etc.) of the hybrid vehicle 1, when a negative torque command is given to the control device 10 and the operation of the inverter device 9 is controlled, the motor generator 7 driven by the rotational power of the drive wheels 2. The three-phase AC power generated from is converted to DC power and supplied to the power storage device 11. Thereby, the converted DC power is charged in the power storage device 11.

  The control device 10 calculates a current command value from the torque command value output from the host control device (not shown), and based on the difference between the current command value and the actual current flowing between the inverter devices 9, the voltage command A value is calculated, a PWM (pulse width modulation) signal is generated based on the calculated voltage command value, and the PWM signal is output to the inverter device 9.

<Modified Example of First Embodiment>
In the cell monitor 50 according to the present invention described with reference to FIG. 3, charge / discharge control of the single cells BC 1, BC 2, BC 3 connected in parallel by ON / OFF control of the switches SW 1, SW 2, SW 3 in addition to the above diagnosis. Can be performed individually to equalize the battery state such as the charged state and the deteriorated state, and conversely to unbalance the battery state.

Here, a method of equalizing the state of charge by controlling the switch element will be described with reference to FIG. Here, as a precondition, it is assumed that the voltage V _{BC3 of the unit} cell BC3 in FIG. 3 is lower than the voltages V _BC1 and V _BC2 of the unit cells BC1 and BC2. Moreover, as explained in the first embodiment, the voltage of the unit cell measured by the cell monitor is not the terminal voltage of the unit cell, but if there is no abnormality in the wiring path, it is easily converted into the terminal voltage of the unit cell. Therefore, in the following description, it is assumed that the terminal voltage of the unit cell is measured by the cell monitor.

First, an operation mode is detected in step S101, and it is determined in step S102 whether charging is in progress. If the battery is being charged, in step S103, the switch SW3 is turned on, SW1 and SW2 are turned off as shown in FIG. 3, and the unit cell BC3 is selected. Thus, only BC3 unit cell is charged, the voltage _{V BC3} of BC3 unit cell increases. This V _BC3 is monitored in step S104.

On the other hand, if step S102 is not charging, it is determined in step S106 whether discharging is in progress. If the battery is being discharged, the switch SW3 is turned off, the switches SW1 and SW2 are turned on in step S107, and the single cells BC1 and BC2 are selected. As a result, only the single cells BC1 and BC2 are discharged, and the voltages V _BC1 and V _BC2 of the single cells BC1 and BC2 decrease. This V _BC1 (= V _BC2 ) is monitored in step S108. If it is determined in step S106 that the battery is not being discharged, it is resting and the process returns to step S101.

Then, if V _BC3 = V _BC1 = V _BC2 is established in step S105, the flow is ended. If not established, the process returns to step S101, and the above steps are repeated.

Here, as a precondition, the voltage V _{BC3 of the unit} cell BC3 has been described as being lower than the voltages V _BC1 and V _BC2 of the unit cells BC1 and BC2, but the voltages of the unit cells BC1 and BC2 are different from those of the other units. Even when the voltage is low, the switches SW1, SW2, and SW3 can be similarly turned on and off to equalize the voltages of the single cells BC1, BC2, and BC3.

  As described above, according to the present invention, the switches SW1, SW2, and SW3 are controlled to be turned on and off in addition to the diagnosis, and the charge / discharge control of the single cells BC1, BC2, and BC3 is performed individually to equalize the charge state of each battery. Is possible.

On the contrary, the switches SW1, SW2, and SW3 are controlled to be turned on and off to individually control the charge and discharge of the single cells BC1, BC2, and BC3, thereby making the charge state of each battery unbalanced. Is possible. It is also possible to control the deterioration state by imbalance the charge / discharge stress applied to each battery by making the charge state of each battery unbalanced.
For example, it is possible to accelerate the deterioration by controlling the battery voltage with a small degree of deterioration higher and charge / discharge with priority, and as a result, the deterioration state can be equalized.

Note that the method of selecting and charging the cell group as described above is such that a plurality of cell groups in which a plurality of single cells are connected in series as described in the third embodiment (FIG. 7) of the present invention are arranged in parallel. Even when connected, charge the cell group by controlling the switch, selecting a cell group, detecting the charge state of this cell group, and charging this cell group as necessary. The state can be equalized.
In addition, as described with reference to FIG. 8 in the third embodiment of the present invention, the state of charge of each single cell included in this series cell group is discharged as needed for each single cell, The state of charge of each unit cell can be equalized.
Thus, by selecting a cell group and performing charging / discharging for each cell group, the charge state of each cell group and each single battery included therein can be equalized.

<Modified example of the second embodiment of the present invention>
The present invention can also be applied to secondary batteries other than lithium batteries.
In FIG. 12, as compared with FIG. 6, a switch is further connected in series to a series cell group in which three cells are connected in series. Or compared with FIG. 8, the cell controller which controls each of three series cell groups 20A1, 20A2, and 20A3 is deleted. This configuration is suitable for a secondary battery having an aqueous electrolyte such as a lead battery, a nickel hydride battery, or a nickel cadmium battery that does not need to monitor the state of each unit cell individually. This modified embodiment can also be applied to a battery module block in which two or more series cell groups are connected in series, in which switches are connected in series and connected in parallel, and the number of parallel connections can be increased. It is.

<Modified Example of Voltage Detection Unit>
FIG. 13 shows a modified example of the voltage detector 51 used in the first and second embodiments according to the present invention. Here, as compared with the circuit of the voltage detection unit 51 shown in FIG. 4, instead of using the switch 63, the both ends on the positive electrode side and the negative electrode side of the voltage detection unit 51 are pulled up or pulled down with a minute current. It is possible to achieve the function. That is, when the voltage detection line SLP, the resistor 61A and the resistor 61B, and the voltage detection line SLN are not correctly connected, the voltage detector 64 detects the pull-up voltage or the pull-down voltage, and diagnoses an abnormality in the voltage detection path. Can do.

  In FIG. 12, a switch 63 and a constant current source 66 are connected in series, and a switch 67 and a constant current source 68 are connected in series. The switch 63 and the switch 67 are connected to both ends of the voltage detector 64. The other ends of the constant current source 802 and the constant current source 804 are connected to the ground. The current values of the constant current sources 802 and 804 are set to a minute current value at a level at which the battery voltage does not decrease.

  At the time of diagnosis, the switches 801 and 803 are turned on. As a result, both ends of the voltage detector 64 are pulled down by the constant current sources 66 and 68, but the current value is set to a minute current value at which the battery voltage does not decrease. A voltage approximately equal to the battery voltage is detected. On the other hand, for example, when the voltage detection line SLP or SLN is not correctly connected, the battery voltage is not applied, and thus a voltage close to zero is detected.

  Here, constant current sources 66 and 68 are connected to both ends of the voltage detector 64 through switches 63 and 67, respectively. This is because the current consumption is reduced by turning on the switches 63 and 67 only at the time of diagnosis, and the voltage detection accuracy is prevented from being lowered. Accordingly, the switches 63 and 67 can be deleted depending on the specifications of current consumption and voltage detection accuracy. Although the case of pulling down by a minute current is shown here, the same function can be achieved by a method of pulling up both ends of the voltage detector 64 to the power supply voltage by the minute current. Thus, by pulling up or pulling down both ends of the voltage detector 64 with a minute current, an abnormality in the voltage detection path can be diagnosed.

<Other modified embodiments>
In the above description of the embodiment of the present invention, the single battery has been described as being a secondary battery such as a lithium ion battery, a nickel hydride battery, a lead battery, and a nickel cadmium battery, and a power storage element such as an ultracapacitor. This path abnormality detection method can be similarly applied to a general battery that is not a secondary battery, for example, a single battery such as a manganese dioxide battery.

  In the first embodiment of the present invention, a single cell and a switch are connected in series to simplify the description, but a plurality of cells and a switch connected in series are parallel. The present invention can also be applied to the case of being connected to.

  Moreover, in 1st Embodiment of this invention, it was set as the structure by which what connected switch SW1-3 in series with each of unit cell BC1-3 in FIG. 3 was connected in parallel. That is, although a parallel cell group in which three cells are connected in parallel is configured, the present invention provides a battery module block in which two or more parallel cell groups are connected in series, parallel, or series-parallel, and the battery module. The present invention is also applicable to battery modules in which blocks are connected in parallel, series, or series-parallel.

  In the first embodiment of the present invention, the two resistors 61A, 62, and 61B are provided in FIG. 4, but these may be deleted depending on the resistance values of the voltage detection lines SLP and SLN. It is also possible to provide a number of resistors.

In the fourth embodiment of the present invention, each cell group is composed of four battery cells, and each battery module block 20A, 20B has two cell groups (20A1, 20A2, 20A3 and 20B1, 20B2, 20B3). It is supposed to be composed of
However, the number of battery cells included in each cell group is not limited to four, and may be five or more. For example, four cell groups and six cell groups may be combined. . The cell controller IC provided for each cell group is designed so that it can be used regardless of whether the number of battery cells included in these cell groups is four or more. can do.
In order to obtain the voltage and current required for electric vehicles and hybrid vehicles, each battery module block may have a plurality of cell groups connected in series or series-parallel as described above, and a plurality of battery module blocks. May be connected in series or series-parallel.

  Although the embodiment and the modification of the present invention have been described above, the present invention is not limited to these contents. Other embodiments conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention.

<FIGS. 1-4, 6-7, 11, 12>
BC1~BC3, BC11~BC14, BC21~BC24, BC31~BC34: rechargeable battery cell _{V BC1, V BC2, V BC3} : rechargeable battery cell BC1～BC3 the terminal voltage _{r BC3:} internal resistance of BC3 secondary battery cells Values 21, 22, 31, 32: Bus bars SLP, SLN, SL1-SL5: Voltage detection lines SL11-15, SL21-25, SL31-35: Voltage detection lines r _SLP , r _SLN : Resistance values CBP of SLP, SLN, CBN, CNP, CMN, CVP, CVN: Connection point Cv: Capacitor SW1-3: Switch IC1-3: Cell controller 50: Cell monitor 51: Voltage detector 52: Switch controller 61A, 61B, 62: Resistor r _61A r _{61B, r 62:} the resistance 61A, 61B, 62 of the resistance 63: switch _{r 63:} Sui Resistance 64 Ji 63: voltage detector 65: switching diagnosis section 66: constant-current source 67: Switch 68: a constant current source 801, 803: switch <8>
120: multiplexer 122A: analog-digital converter 123: IC control circuit 130: diagnostic circuits 138 and 142: transmission input circuits 140 and 143: transmission output circuit 147: start-up circuit 150: timer circuit 160: control signal detection circuit 262 differential amplifier 288: OR circuits BC1 to BC4: Battery cell 123: IC control circuit 125: Data holding circuit IC1: Cell control IC
126: Timing control circuit 130: Diagnostic circuit 128: Diagnostic flag holding circuits BR1 to BR4: Balancing terminals CV1 to CV4: Voltage input terminals GND: GND terminals SL1 to SL5: Voltage detection lines VCC and VDD: Power supply voltages Cv and Cin: Capacitors RCV and RB: Resistor PH: Photocoupler LIN1: Input terminal LIN2 of communication system 602: Input terminal of communication system 602 FFI: Input terminal of communication system 604 FFO: Output terminals D1 and D2 of communication system 604: ESD countermeasure diode <Fig. 9>
20: Battery module 20A, 20B: Battery module block 30: Microcomputer 100: Battery control device 9: Inverter devices 602, 604: Communication system IC1 to IC4: Cell controller IC
SD-SW: Service disconnect (switch)
RC-net: wiring circuit portion including protection circuit and discharge circuit <FIG. 13>
1: Hybrid vehicle 2: Drive wheel 3: Axle 4: Differential gear 5: Transmission 6: Engine 7: Motor generator 8: Driving force switching device 9: Inverter device 10: Control device 11: Power storage devices HV + and HV-: High-voltage line RL: Relay RP: Resistor RLP: Precharge relay BDU: Battery disconnect unit

Claims (9)

And the battery module first switch and is and one or more unit cells and cell groups connected in series, connected in parallel a plurality or series-parallel,
A battery control device comprising: a switch control unit that switches the first switch to select a cell group; and a first voltage detection unit that detects a voltage of the cell group selected by the switch control unit ;
Based on the voltage detected by the first voltage detecting unit, and a diagnostic means for diagnosing abnormal connection anomaly and the battery modules of the battery module,
The first voltage detector includes a first voltage detector, a first resistor, and a second switch, and the first resistor and the second switch connected in series are the first voltage detector. power storage device which is characterized that it is connected in parallel to the first voltage detector. The power storage device according to claim 1,
The battery control device further includes a second voltage detection unit that detects a voltage applied to the first switch of the cell group selected by the switch control unit,
An abnormality of the first switch of the cell group is diagnosed based on the voltage detected by the second voltage detector. The power storage device according to claim 2 ,
The second voltage detector includes a second voltage detector, and a second resistor and a third switch connected in series are connected in parallel to the second voltage detector. A power storage device. The power storage device according to any one of claims 1 to 3,
The battery control device further includes a plurality of cell controllers, and each cell controller detects a charging state of each unit cell included in each corresponding cell group, and discharges each unit cell, A power storage device that equalizes the state of charge of each unit cell. The power storage device according to any one of claims 1 to 4,
The battery control device controls the first switch by the switch control unit to select a cell group, detect a charge state of the cell group, and charge the cell group as necessary. A power storage device that equalizes the state of charge of the cell group. The power storage device according to any one of claims 4 and 5,
When the abnormal state of the cell group is detected by detecting the state of charge of each unit cell and the connection of the battery module, the first switch of the abnormal cell group is controlled to remove the cell group from the battery module. A power storage device characterized by being separated. Using the power storage device according to any one of claims 1 to 4,
A method for charging / discharging a power storage device comprising: controlling a first switch to select a cell group; charging or discharging the selected cell group; and equalizing a charge state of the cell group. . Using the power storage device according to any one of claims 4 and 5,
When the abnormal state of the cell group is detected by detecting the state of charge of each unit cell and the connection of the battery module, the first switch of the abnormal cell group is controlled to remove the cell group from the battery module. A method for operating a power storage device, characterized in that the battery function is continuously provided by disconnecting and remaining cells. The power storage device according to any one of claims 1 to 6,
A vehicle capable of electric traveling, comprising: a traveling motor driven by electric power controlled by the power storage device.

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