JP2016031879A - Vehicle battery controller - Google Patents

Abstract

The present invention relates to a battery control device for a vehicle, which efficiently suppresses deterioration of the battery while ensuring the running performance of the vehicle. A vehicle battery control device 2 includes two or more batteries 1A and 1B capable of supplying electric power to a traveling motor 3, and driving force supply devices 1C and 4 which are separate sources of driving force. Is provided. Examples of the driving force supply devices 1C and 4 include a generator 4 and a battery 1C. Moreover, the acquisition part 2A which acquires the charge rate of each battery 1A, 1B and the deterioration acceleration area | region which is a charge rate area | region where battery deterioration is accelerated | stimulated is provided. Furthermore, when the driving force supply devices 1C and 4 are the driving force supply sources, the batteries 1A and 1B are set as adjustment batteries, and the charging rates of the batteries 1A and 1B are set so that the respective charging rates are separated from the deterioration acceleration region. An adjustment control unit 2C that moves electric power between the two is provided. [Selection] Figure 2

Description

  The present invention relates to a battery control device that supplies electric power to a vehicle driving motor.

  2. Description of the Related Art Conventionally, in vehicles such as electric vehicles and hybrid vehicles, a technique for limiting the charge / discharge state according to the charging rate (storage capacity) of a vehicle driving battery is known. For example, when regenerative power generation is performed in a state where the charging rate is high, the battery is overcharged, which may cause heat generation or deterioration of the battery. Further, if the battery is continuously discharged in a state where the charging rate is low, not only the deterioration due to the overdischarge of the battery proceeds, but also the vehicle cannot travel. Therefore, the battery performance and the vehicle running performance are ensured by limiting the charging / discharging according to the charging rate of the battery (see Patent Document 1).

  By the way, the deterioration of the battery gradually proceeds even if it is not overcharged or overdischarged, and the deterioration rate changes according to the charging rate. Although the relationship between the charging rate and the deterioration rate varies depending on the type of battery and the usage environment conditions (temperature, humidity, etc.), the deterioration rate takes an extreme value in the normal use state between the overcharge state and the overdischarge state. There are also secondary batteries with special characteristics. Therefore, it has been proposed to control the charge / discharge state in consideration of the relationship between the charging rate of the battery and the deterioration rate.

  For example, it has been proposed to grasp in advance a deterioration acceleration region, which is a charging rate region where the battery deterioration rate increases, and to control charging / discharging so that the actual charging rate does not enter the deterioration acceleration region for a long time. (See Patent Document 2). In this case, when the actual charging rate passes through the deterioration acceleration region, by increasing the amount of change in the charging rate per unit time, the time when the actual charging rate is located in the deterioration acceleration region is shortened, Progress of battery deterioration is suppressed.

International Publication No.2012 / 008462 JP 2012-65449 A

  However, since the running state of the vehicle changes every moment according to the driving operation of the driver, the charging / discharging state of the battery for driving the vehicle frequently varies depending on the running state of the vehicle. For this reason, in conventional battery control, the charge / discharge state during vehicle travel cannot be appropriately controlled, and the time during which the actual charging rate is located in the deterioration acceleration region may become long. That is, it is difficult to control the charge / discharge state while the vehicle is running, and it is difficult to suppress the progress of battery deterioration. On the other hand, if the control for suppressing the progress of battery deterioration is prioritized prior to the control for running the vehicle, the battery power cannot be freely used for running the vehicle, and the running performance of the vehicle may be reduced. Occurs.

  One of the purposes of the present invention was devised in view of the above-described problems, and a battery control device that can efficiently suppress deterioration of a battery while ensuring the running performance of the vehicle. Is to provide. It should be noted that the present invention is not limited to this purpose, and is an operational effect that is derived from each configuration shown in “Mode for Carrying Out the Invention” to be described later. Can be positioned as a purpose.

(1) A battery control device for a vehicle disclosed herein includes two or more batteries that supply electric power to a motor for traveling to transmit driving force to wheels, and a driving force supply device that is a supply source of the driving force. And a battery control device for a vehicle.
The battery control device includes an acquisition unit that acquires a charge rate of each of the batteries and a deterioration acceleration region that is a charge rate region in which battery deterioration is promoted. When the driving force supply device is the supply source of the driving force, at least two of the batteries are set as adjustment batteries, and the adjustment rate is set so that the respective charging rates are separated from the deterioration acceleration region. An adjustment control unit that moves power between the batteries is provided.

  The “driving force supply device” referred to here is, for example, an engine mounted on the vehicle, a generator mounted on the vehicle, a battery different from the two or more batteries, or the like. The “driving force supply device” may generate a driving force and supply the driving force to the wheels, or may transmit the driving force to the motor by supplying energy to the motor. It may be a thing.

  Here, “when the driving force supply device is the driving force supply source” refers to a case where the vehicle is using the driving force supply device as the driving force supply source. In other words, it means that the vehicle is running. Accordingly, the adjustment control unit sets two or more adjustment batteries from among the batteries that are not used for running the vehicle while the driving force supply device is running the vehicle. Electric power is moved between the adjustment batteries.

(2) Preferably, the driving force supply device is a generator, and the electric power from the generator is supplied to the traveling motor to transmit the driving force to the wheels.
(3) Alternatively, it is preferable that the driving force supply device is a power storage device, and the power from the power storage device is supplied to the traveling motor so that the driving force can be transmitted to the wheels. In this case, one or more of the two or more batteries and the power storage device are set as a travel battery, and the drive control unit is configured to supply the electric power of the travel battery to the motor. It is preferable to further comprise.

  Moreover, it is preferable that the said acquisition part acquires the charge rate of the said electrical storage apparatus, and the deterioration acceleration area | region which is a charge rate area | region where battery deterioration is accelerated | stimulated. Further, the adjustment control unit sets the two or more batteries excluding the traveling battery or the power storage device as an adjustment battery, and the adjustment battery so that each of the charging rates is separated from the deterioration acceleration region. It is preferable to move power between the two.

(4) It is preferable to include a power supply circuit that connects the motor and the battery for traveling, and an adjustment circuit that is provided independently of the power supply circuit and connects between the adjustment batteries.
(5) A switch for switching the power supply destination of the battery between the power supply circuit and the adjustment circuit, and a converter that is interposed on the adjustment circuit and controls each voltage of the adjustment battery. preferable.

(6) It is preferable that the drive control unit resets another traveling battery when the charging rate of the traveling battery enters from the outside of the deterioration acceleration region to the inside of the deterioration acceleration region.
For example, when the charging rate of the battery for traveling enters the deterioration acceleration region, power supply to the motor by the battery may be stopped and another battery may be reset as the new traveling battery. preferable. In other words, it is preferable that the battery in charge of the traveling battery is changed (switched) so that the charging rate of the traveling battery does not enter the deterioration acceleration region as much as possible.

(7) It is preferable that the said adjustment battery contains the electrical storage device with which the said deterioration acceleration area | region is narrower than the said battery for driving | running | working.
Specific examples of the traveling battery include a lithium ion secondary battery containing manganese (manganese-based or ternary-based) as a positive electrode active material. Specific examples of the electricity storage device include a lithium ion secondary battery, an electrochemical capacitor, and a proton capacitor. Examples of positive electrode active materials for lithium ion secondary batteries include olivine (LiMPO ₄ ), fluorinated olivine (Li ₂ MPO ₄ F), silicate (Li ₂ MSiO ₄ ), and layered oxide (LiMO ₂ ), spinel (LiM ₂ O ₄ ), vanadium (LiV ₃ O ₈ ), perovskite (LiFeF ₃ ), etc. (M is nickel Ni, cobalt Co, iron Fe, aluminum Al, etc.) Represents).

  (8) It is preferable that the vehicle includes a generator connected to the adjustment circuit, and the adjustment control unit supplies electric power generated by the generator to a charging target of the adjustment battery.

  According to the vehicle battery control device disclosed herein, it is possible to efficiently suppress the deterioration of the adjustment battery while ensuring the running performance of the vehicle, and to extend the life of the entire battery.

It is a figure which shows the vehicle to which the battery control apparatus which concerns on an Example was applied. It is a circuit diagram which illustrates the electric circuit which concerns on control by a battery control apparatus. It is a graph for demonstrating the characteristic of a battery. It is a flowchart which illustrates the control procedure in a battery control apparatus. (A)-(D) are the figures for demonstrating the control content in a battery control apparatus. It is a circuit diagram which illustrates the electric circuit which concerns on a modification.

  A vehicle battery control apparatus as an embodiment will be described with reference to the drawings. The embodiment described below is merely an example, and there is no intention of excluding various modifications and technical applications that are not explicitly described in the following embodiment. Each configuration of the present embodiment can be implemented with various modifications without departing from the spirit of the present embodiment, and can be selected or combined as necessary.

[1. Device configuration]
FIG. 1 illustrates a vehicle 10 to which the battery control device of this embodiment is applied. The vehicle 10 is a series hybrid vehicle equipped with a battery 1 for driving the vehicle. The power train of the vehicle 10 is provided with a front motor 3A that drives the front wheels and a rear motor 3B that drives the rear wheels. These motors 3 are motor generators (motors / generators) that have both a function as a motor and a function as a generator. The DC power stored in the battery 1 is converted into AC power by the inverter 6 and then fed to each motor 3. Further, the regenerative power generated by each motor 3 is converted into DC power via the inverter 6 and stored in the battery 1.

  The vehicle 10 is equipped with a generator 4 and an engine 5. The engine 5 is a prime mover that drives the generator 4 to generate electric power, and is controlled so as to continue operation in a rotational speed region where engine efficiency is high as necessary when a predetermined generator operating condition is satisfied. The generator 4 is a motor generator (motor / generator) having both a function of generating electric power using the power of the engine 5 and a function of starting the engine 5. The generated power generated by the generator 4 can be directly supplied to the motor 3, and in addition to this, the battery 1 can be charged via the inverter 6.

  The vehicle 10 is also equipped with a charging port for external charging (not shown), an in-vehicle charger for charging the battery 1 by converting electric power supplied from an external power source into DC power. For example, when an external power source is available, external charging is performed, and even when the external power source is not available, charging can be performed with power generated by regenerative power generation or private power generation so that the vehicle 10 can continue to travel. is there.

  The charging / discharging state of the battery 1 and the operating states of the motor 3, generator 4, engine 5, inverter 6 and the like are controlled by the control device 2 (battery control device, PHEV-ECU). The control device 2 is one of electronic control units mounted on the vehicle 10. For example, a microprocessor such as a CPU (Central Processing Unit) and an MPU (Micro Processing Unit), a ROM (Read Only Memory), a RAM ( Random Access Memory), auxiliary storage devices, interface devices, etc. LSI devices and embedded electronic devices. The control device 2 comprehensively controls and manages the operating state of various devices included in the power train, the traveling state of the vehicle 10, and the like. The control device 2 is connected to a communication line of an in-vehicle network network (not shown) and is provided so as to be able to communicate with another in-vehicle electronic control unit (for example, an engine control unit, a battery management unit, etc.). .

  In the present embodiment, among the various controls performed by the control device 2, two controls, namely, drive control and adjustment control will be mainly described. The drive control is control that causes the vehicle 10 to travel by supplying electric power from the battery 1 to the motor 3. On the other hand, adjustment control is control which adjusts the value of each charging rate, maintaining the total stored electric power by mutually transferring the electric power stored in each of the plurality of batteries 1. These controls can be performed in parallel (can proceed simultaneously). That is, the adjustment control is performed not only when the vehicle 10 is stopped or when externally charged, but also when the vehicle 10 is traveling. Hereinafter, a circuit configuration and a control configuration for performing these controls will be described in order.

[2. Circuit configuration]
As shown in FIG. 2, at least three or more batteries 1 that can supply electric power to the motor 3 are provided on the circuit of the present embodiment. Here, for convenience, they are referred to as a first battery 1A, a second battery 1B, and a third battery 1C. The types of these batteries 1A to 1C can be arbitrarily set. For example, secondary batteries such as lithium ion batteries, nickel metal hydride batteries, lithium air batteries, all solid batteries, electric double layer capacitors, aluminum electrolytic capacitors, proton capacitors, etc. The electrochemical capacitor may be used. Further, the electric capacity and charge / discharge characteristics of the individual batteries 1A to 1C can be arbitrarily set, and the types and electric capacities of the individual batteries 1A to 1C do not need to be set to be the same.

  The electric power of each of the batteries 1A to 1C is supplied to the motor 3 through the power supply circuit 11 which is a drive control circuit. Of the two motors 3, the front motor 3A is connected to the power feeding circuit 11 via the first inverter 6A, and the rear motor 3B is connected to the power feeding circuit 11 via the second inverter 6B. Since the dedicated inverters 6A and 6B are provided for the front and rear motors 3A and 3B, the driving forces of the front and rear wheels are individually controlled, and the vehicle running performance is improved. The generator 4 is connected to a high voltage circuit between the front motor 3A and the first inverter 6A.

  On the other hand, the adjustment circuit 12 that is a circuit for adjustment control is provided independently of the power feeding circuit 11. The adjustment circuit 12 is formed by branching from a circuit connecting the battery 1 and the inverter 6 so as to connect the individual batteries 1. That is, the adjustment circuit 12 is connected to the branch circuit from the power supply circuit 11 connected to the first battery 1A, the branch circuit from the power supply circuit 11 connected to the second battery 1B, and the third battery 1C. It is formed by connecting the branch circuit from the feeding circuit 11 that is present.

  An electromagnetic switching type switch 7 is interposed at a branch point between the feeding circuit 11 and the adjustment circuit 12. These switches 7 have a function of switching a circuit to which the battery 1 is connected. In the switch 7 of this embodiment, the switching position is controlled to three positions: a power feeding position, an adjustment position, and an off position. The power supply position is a position for guiding the power of the battery 1 to the power supply circuit 11, and the adjustment position is a position for guiding the power of the battery 1 to the adjustment circuit 12. The off position is a position for cutting off the electric power of the battery 1 and maintaining the storage state.

  In the circuit in FIG. 2, there are three branches between the power feeding circuit 11 and the adjustment circuit 12 (that is, the number of the batteries 1 is three), so that three switches 7A, 7B, and 7C are provided. By controlling the connection state of each switch 7, the power supply state and the power supply direction of each battery 1 can be individually controlled. A converter 8 is interposed in the vicinity of each switch 7 on the adjustment circuit 12. The converter 8 is a transformer that controls the value of the DC voltage of each battery 1.

  Hereinafter, the switch 7 and the converter 8 related to the first battery 1A are referred to as a first switch 7A and a first converter 8A. Similarly, those related to the second battery 1B are called the second switch 7B and the second converter 8B, and those related to the third battery 1C are called the third switch 7C and the third converter 8C. The operation states of the switches 7A to 7C and the converters 8A to 8C are controlled by the control device 2.

[3. Control configuration]
The control device 2 includes an acquisition unit 2A, a drive control unit 2B, and an adjustment control unit 2C as functional elements for performing drive control and adjustment control. These elements may be realized by an electronic circuit (hardware), may be programmed as software recorded and stored in a ROM or an auxiliary storage device, or may have a part of these functions. It may be provided as hardware and the other part may be software.

[3-1. Acquisition Department]
The acquisition unit 2A acquires the state of charge (SOC) and the deterioration acceleration region of each of the batteries 1A to 1C. The deterioration acceleration region means a charge rate region where the battery deterioration is promoted (a charge rate region where deterioration is likely to accelerate). The battery deterioration here includes a decrease in full charge capacity, a decrease in storage stability (capacity maintenance ratio), and the like. Moreover, the charge rate area | region where deterioration is accelerated | stimulated is defined as the range of the charge rate of the battery 1A-1C with respect to each battery 1A-1C. For example, when the change in the deterioration rate with respect to the charging rate (the rate at which the full charge capacity decreases or the rate at which the capacity maintenance rate decreases) is represented by a graph as shown in FIG. ₁ -C ₂ is a deterioration acceleration region. Alternatively, a range in which the capacity maintenance rate during the predetermined period is equal to or less than the predetermined maintenance rate is set as the deterioration acceleration region. The deterioration acceleration region is not necessarily a single range, and each battery 1 may have a plurality of deterioration acceleration regions.

  The charging rate is calculated and estimated based on, for example, the voltage of each of the batteries 1A to 1C, the integrated value of charge / discharge current, the usage time, and the like. In addition, the deterioration acceleration region is set in advance through experiments and tests as being in accordance with the types of the batteries 1A to 1C. Or based on the voltage at the time of a full charge, a full charge capacity, use time, etc., you may calculate and estimate suitably. Information on the charging rate and deterioration acceleration region acquired by the acquiring unit 2A is transmitted to the drive control unit 2B and the adjustment control unit 2C. The information on the charging rate and the deterioration acceleration area may be obtained (detected) by the acquisition unit 2A, calculated based on the actual measurement value, or other vehicle-mounted electronic control unit (for example, The information detected, calculated, and estimated by the battery management unit) may be transmitted to the control device 2.

[3-2. Drive control unit]
The drive control unit 2 </ b> B performs drive control, and has a function of setting one of the three batteries 1 </ b> A to 1 </ b> C as a travel battery and supplying electric power of the travel battery to the motor 3. . Here, the total number of batteries 1 is set to N, and the number of traveling batteries is set to M. The number M of traveling batteries is set to be at least 1 and the number NM of batteries other than the traveling battery is at least 2 (1 ≦ M ≦ N−2, M is a natural number, N is 3 More natural numbers). Accordingly, when the number of the batteries 1 is four, one or two batteries 1 are set as the traveling batteries.

  The travel battery setting conditions are arbitrary. For example, the battery with the highest charging rate (with a relatively high charging rate) among the three batteries 1A to 1C may be set as the traveling battery, or the battery with the lowest charging rate (with a relatively low charging rate). May be set as a battery for traveling. Alternatively, the battery for traveling may be set based on the degree of deterioration of the batteries 1A to 1C (selecting a battery with a high degree of deterioration or selecting a battery with a low degree of deterioration). Moreover, it is good also as all the batteries 1A-1C being set to a battery for driving | running | working in order in the order set beforehand. Preferably, the battery 1 whose charging rate is not located in the deterioration acceleration region is selected as the traveling battery at that time.

  The drive control unit 2B provides a control signal for switching the switches 7A to 7C corresponding to the batteries 1A to 1C to the power feeding position so that the batteries 1A to 1C set as the traveling battery are connected to the power feeding circuit 11. Output. By such drive control, the traveling battery is connected to the motor 3 and the inverter 6, and the traveling performance of the vehicle 10 is ensured. Further, since the switches 7A to 7C corresponding to the batteries 1A to 1C are switched to the power feeding circuit 11 side, the battery for traveling is excluded from the target of the adjustment control.

[3-3. Adjustment control unit]
The adjustment control unit 2C performs adjustment control, and has a function of setting two of the three batteries 1A to 1C as adjustment batteries and moving electric power between them. The number of adjustment batteries is set to 2 or more. Note that all the batteries 1 other than the traveling battery may be set as adjustment batteries, but at least two or more adjustment batteries may be set from other than the traveling batteries. The adjustment control unit 2C controls the charge / discharge state of each adjustment battery so that the respective charging rates of the adjustment batteries are separated (disengaged) from the deterioration acceleration region.

  The adjustment control unit 2C outputs a control signal for switching the switches 7A to 7C corresponding to the batteries 1A to 1C to the adjustment position in order to move the power of the adjustment batteries to each other. As a result, the adjustment batteries are connected to each other, and power can be transferred between the batteries 1. Moreover, since the converter 8A-8C corresponding to each battery 1A-1C is interposed in the adjustment circuit 12, regardless of the magnitude of the open circuit voltage of each battery 1A-1C, charging of each battery 1A-1C is possible. The discharge state can be controlled. When the number of the batteries 1 is four or more, the switch 7 corresponding to the battery 1 that is neither the traveling battery nor the adjusting battery is controlled to the off position.

Further, the adjustment control unit 2C determines the battery 1 to be charged and the battery 1 to be discharged among the adjustment batteries based on the relationship between the charging rate of each adjustment battery and the deterioration acceleration region, The amount of power to be moved from the discharge target to the charge target is determined. The method for setting the discharge target, charge target, and electric energy is arbitrary. For example, the difference between the central value [(C ₁ + C ₂ ) / 2] of the deterioration acceleration region and the charge rate value is calculated for each adjustment battery. When the charging rates of the respective adjustment batteries are all greater than the center value, it is conceivable that the battery with the largest difference is the discharge target and the battery with the smallest difference is the charge target. Further, when the charging rates of the respective adjustment batteries are all smaller than the center value, it is conceivable that the battery with the smallest difference is the discharge target and the battery with the largest difference is the charge target. The amount of electric power may be determined so that the difference between the charging rate for each adjustment battery and the center value of the deterioration acceleration region is equal. Alternatively, the charge rate of the charge target is greater than or equal to the upper limit value (C ₂ ) of the deterioration acceleration region, and the charge rate of the discharge target is greater than or equal to the upper limit value (C ₂ ) of the deterioration acceleration region or less than the lower limit value (C ₁ ). In this way, the amount of power may be determined.

The adjustment control unit 2C allows the charge rate of each adjustment battery to move away from the deterioration acceleration region (moves in a direction away from a position close to the deterioration acceleration region, or the charge rate located in the deterioration acceleration region deteriorates. Set the direction of power delivery and the amount of power so that it moves in a direction away from the acceleration region. Here, the action of “the charge rate leaves the deterioration acceleration region” means that the charge rate is changed so that the degree of deterioration is low in total. With such adjustment control, the distribution of the amount of stored electricity changes while the amount of stored electricity in the entire battery 1 is maintained, and the deterioration of the individual batteries 1A to 1C is less likely to proceed.
In addition, the adjustment control unit 2C monitors the voltage, current, charge / discharge amount, and the like of the adjustment battery in the adjustment control process, and determines whether or not the power transfer (charging of the charging target) is completed. The adjustment control is continued until the power transfer is completed. When the power transfer is completed, the switches 7A to 7C corresponding to the adjustment batteries are switched to the off position, and the adjustment control ends.

[3. flowchart]
FIG. 4 is a flowchart illustrating the procedure of drive control and adjustment control. As described above, the drive control and the adjustment control can be performed in parallel, and each of them can be represented by separate flowcharts. On the other hand, here, a flow in the case where drive control and adjustment control are executed in sequence within one calculation cycle is shown. This flow is repeatedly executed in the control device 2 at a predetermined cycle.

  In Step A1, the acquisition unit 2A of the control device 2 acquires the charging rate and deterioration acceleration region information of each of the batteries 1A to 1C. In step A2, one battery 1 is set as a traveling battery in the drive control unit 2B. In this flow, it is assumed that the battery 1 whose charging rate is located outside the deterioration acceleration region is set as the traveling battery. Further, if the traveling battery has already been set in the previous calculation cycle, the process proceeds to the next step as it is.

  In step A3, it is determined whether or not the charging rate of the traveling battery is located outside the deterioration acceleration region. This step is a step related to condition determination for changing or updating the allocation of the battery for traveling. When this condition is satisfied, the process proceeds to step A4 without updating the traveling battery, the switching positions of the switches 7A to 7C corresponding to the traveling battery are switched to the power feeding position, and the drive control is performed. Thereby, the electric power of the battery for driving | running | working is supplied to the inverter 6 side, and the motor 3 is driven.

  On the other hand, when the condition of step A3 is not satisfied, the process proceeds to step A9, the battery for traveling is updated, and the control of this cycle ends. For example, when the charging rate of the traveling battery gradually falls during the traveling of the vehicle 10 and enters the deterioration acceleration region, another traveling battery is reset. A new battery for traveling may be reset at step A2 of the next calculation cycle.

If drive control is implemented by step A4, two battery 1 other than a battery for driving | running | working will be set as a battery for adjustment in step A5 following it by the adjustment control part 2C. Further, in step A6, each battery 1 to be charged and discharged among the adjustment batteries is determined, and the respective charge / discharge amounts (moving electric energy) are determined.
In subsequent Step A7, it is determined whether or not the power transfer of the adjustment battery is completed. This step is a step related to condition determination for ending adjustment control. For example, when all the adjustment batteries are fully charged, or when the amount of power determined in step A6 has been moved, this condition is satisfied, and the process proceeds to step A8. If this condition is not satisfied, the process proceeds to step A10.

  In step A8, the adjustment control is not performed, and the control of this cycle ends. In this case, only drive control is continued. On the other hand, in step A10, the switching position of the switches 7A to 7C corresponding to the adjustment battery is switched to the adjustment position, the adjustment control is performed, and the control of this cycle ends. The adjustment control performed in step A10 is performed in parallel with the drive control performed in step A4. Thereby, electric power is transferred from the discharge target of the adjustment battery to the charge target. Further, in each of the discharge target and the charge target, the respective charge / discharge states are controlled so that the charge rate moves in a direction away from the deterioration acceleration region.

[4. Action]
FIGS. 5A to 5D illustrate changes in the charging rates of the batteries 1A to 1C due to the travel control and the adjustment control. Here, it is assumed that the full charge capacities of the batteries 1 are substantially the same, and the deterioration acceleration region is in the range C _{1 to} C ₂ . First, when all the batteries 1A to 1C are fully charged, only one of them is set as a traveling battery, and drive control is performed. Assuming that the third battery 1C is initially set as a traveling battery, the charging rate of the third battery 1C gradually decreases as the vehicle 10 travels. At this time, since the first battery 1A and the second battery 1B are fully charged, the adjustment control is not performed.

As shown in FIG. 5 (A), the charging rate of the third battery 1C is a driving battery enters the deterioration acceleration region and (charging rate is reduced to C _2), the drive control unit 2B is a traction battery The first battery 1A is set as a new traveling battery by changing or updating. At this time, the second battery 1B and the third battery 1C are set as adjustment batteries, and adjustment control for moving electric power is performed.

In this adjustment control, the charge / discharge state is controlled so that the charging rates of the second battery 1B and the third battery 1C are both separated from the deterioration acceleration region. For example, the second battery 1B, so that the charging rate of the third battery 1C is slightly larger state than both C _2, power is transferred from the second battery 1B to the third battery 1C. Thereby, the progress of deterioration of the third battery 1C is suppressed as compared with the case where the third battery 1C is continuously used as the traveling battery or the case where the state shown in FIG. Further, as shown in FIG. 5 (B), the second battery 1B, becomes slightly greater state than the charging rate are both C ₂ of the third battery 1C, adjustment control is completed, the drive control only is continued.

Thereafter, as shown in FIG. 5 (C), the charging rate of the first battery 1A enters the deterioration acceleration region (charging rate is reduced to C _2), changes the driving battery again, such as a tertiary battery 1C is set as a new traveling battery. At this time, the first battery 1 </ b> A and the second battery 1 </ b> B are set as adjustment batteries, and adjustment control for moving power from the second battery 1 </ b> B to the first battery 1 </ b> A is performed.

Thereafter, the charge / discharge state is controlled such that the charging rates of the first battery 1A and the second battery 1B are both out of the deterioration acceleration region. For example, power is transferred from the second battery 1B to the first battery 1A so that the charging rate of the first battery 1A is greater than C ₂ and the charging rate of the second battery 1B is C ₁ or less. Thereby, compared with the case where 1 A of 1st batteries are used continuously as a battery for driving | running | working, or the case where the state shown in FIG.5 (C) is continued, progress of deterioration of 1st battery 1A is suppressed. Further, as shown in FIG. 5D, when the charging rates of the first battery 1A and the second battery 1B are both out of the deterioration acceleration region, the adjustment control is terminated and only the drive control is continued. Such control is sequentially repeated, and the respective charge / discharge states are controlled so that the time during which the charging rates of the batteries 1A to 1C exist in the deterioration acceleration region is shortened.

[5. effect]
(1) In the control of the present embodiment, drive control using at least one of the batteries 1A to 1C as a travel battery is performed, and adjustment control for moving electric power among a plurality of adjustment batteries other than the travel battery. Implemented in parallel with drive control. With such a control configuration, it is possible to suppress the progress of deterioration of the battery 1 as a whole while ensuring the traveling property of the vehicle 10, and to extend the life (lifetime) of the battery 1.

  (2) In the electric circuit connected to the battery 1 of the present embodiment, as shown in FIG. 2, a power feeding circuit 11 (that is, for driving control) that connects the battery for traveling and the motor 3 via the inverter 6 Circuit). On the other hand, the adjustment control adjustment circuit 12 is provided independently of the power feeding circuit 11 and is provided so as to connect between the adjustment batteries. With such a circuit configuration, it is possible to electrically separate power feeding and power transfer for driving the vehicle 10, and to perform drive control and adjustment control independently of each other. In other words, even when the vehicle 10 is traveling, it is possible to freely adjust the charging rate by moving power between the adjustment batteries, thereby enhancing the effect of improving both the traveling performance and the deterioration suppressing effect. Can do.

  (3) Further, as shown in FIG. 2, a switch 7 for switching a circuit to which the battery 1 is connected to the power feeding circuit 11 and the adjustment circuit 12 and a converter 8 for controlling the voltage of the adjustment battery are provided. . With such a circuit configuration, electric power can be freely transferred regardless of the voltage level of the adjustment battery. For example, as shown in FIGS. 5C and 5D, power transfer from the low charge rate side to the high side is facilitated.

  (4) In the control of the present embodiment, when the battery 1 whose charging rate is not located in the deterioration acceleration region is selected as the traveling battery, and the charging rate of the traveling battery enters the deterioration acceleration region, The traveling battery is changed, that is, another traveling battery is reset. As a result, the time during which the charging rate of the battery for traveling is outside the deterioration acceleration region can be prolonged as much as possible, and the deterioration suppressing effect of the battery 1 can be further enhanced.

[6. Modified example]
Regardless of the embodiment described above, various modifications can be made without departing from the spirit of the invention. Each structure of this embodiment can be selected as needed, or may be combined appropriately. For example, in FIGS. 5A to 5D, the case where the full charge capacities of the batteries 1 </ b> A to 1 </ b> C are substantially the same has been described, but the types of these batteries 1 </ b> A to 1 </ b> C can be arbitrarily set. A plurality of batteries 1 may include an electricity storage device having a narrow deterioration acceleration region, and this may always be used as an adjustment battery.

As a specific example of the battery for traveling, a lithium ion secondary battery containing manganese (manganese-based or ternary-based) as a positive electrode active material is used. On the other hand, it is conceivable to use a generator, a fuel cell, a high-performance lithium ion secondary battery with good deterioration characteristics, an electrochemical capacitor, a proton capacitor, or the like as an adjustment power source (battery). Examples of positive electrode active materials for high-performance lithium ion secondary batteries include olivine (LiMPO ₄ ), fluorinated olivine (Li ₂ MPO ₄ F), silicate (Li ₂ MSiO ₄ ), and layered oxidation. Physical system (LiMO ₂ ), spinel system (LiM ₂ O ₄ ), vanadium system (LiV ₃ O ₈ ), perovskite system (LiFeF ₃ ), etc. (M is nickel Ni, cobalt Co, iron Fe, aluminum Al, etc.) Represents a metal). By using a power storage device having a narrow deterioration acceleration region, it is possible to more flexibly adjust the moving direction and moving amount of power delivered by adjustment control, and to improve controllability. Thereby, it becomes easy to remove the charging rate of the adjustment battery from the deterioration acceleration region, and deterioration of the adjustment battery can be efficiently suppressed.

  Moreover, it is good also as a control structure which implements adjustment control using the electric power generated with the generator 4. FIG. For example, as shown in FIG. 6, it is conceivable that a third inverter 6C is interposed on a high voltage circuit connecting the generator 4 and the motor 3 to convert the generated power into direct current and then flow into the adjustment circuit 12. . In this case, the power transfer in the adjustment battery is assisted by the generated power, and the generated power is supplied to the charging target in the adjustment battery. Therefore, it is possible to increase the charging speed of the charging target in the adjustment battery, and it is possible to suppress a decrease in the charging rate of the discharge target, and it is possible to efficiently suppress deterioration of the adjustment battery.

  Moreover, although the above-mentioned embodiment showed the circuit in which the at least 3 or more battery 1 which can supply electric power to the motor 3 was provided, the number of the batteries 1 should just be two at the minimum. In this case, apart from these two batteries 1A and 1B, there may be a driving force supply device as a driving force supply source. This “driving force supply device” may generate a driving force and supply the driving force to the wheels, or may transmit the driving force to the motor 3 by supplying energy to the motor 3. May be. That is, the “driving force supply device” is, for example, the engine 5 mounted on the vehicle 10, the generator 4 mounted on the vehicle 10, the battery 1 </ b> C other than the batteries 1 </ b> A and 1 </ b> B, and the like.

  At least, when the driving force supply device is a driving force supply source, the adjustment control unit 2C may move power between the batteries 1A and 1B. Here, “when the driving force supply device is a driving force supply source” means that the vehicle 10 is in a state of using the driving force supply device as a driving force supply source. This means that the vehicle 10 is traveling. Therefore, the adjustment control unit 2C sets two or more adjustment batteries 1A and 1B from the batteries 1 that are not used for running the vehicle 10 while the driving force supply device is running the vehicle 10. At the same time, power is moved between the adjustment batteries 1A and 1B. Even in such control, the same effects as those of the above-described embodiment can be obtained.

  In the above-described embodiment, the control of the battery 1 mounted on the series hybrid vehicle has been described, but the type of vehicle to which the control of the present embodiment is applicable is not limited to this. For example, it can be applied to a parallel hybrid vehicle or an electric vehicle. If the vehicle is equipped with at least two batteries 1 that can supply power to the traveling motor 3 and other driving force supply devices (for example, the battery 1C, the generator 4, the engine 5, and the like), The control of the embodiment can be applied, and the same effect as the above-described embodiment can be obtained.

1 Battery (power storage device, driving force supply device)
2 battery control device 2A acquisition unit 2B drive control unit 2C adjustment control unit 3 motor 4 generator (driving force supply device)
5 Engine (drive power supply device)
6 Inverter 7 Switch 8 Converter 10 Vehicle 11 Feeding circuit 12 Adjustment circuit

Claims (8)

In a battery control device for a vehicle equipped with two or more batteries for supplying electric power to a motor for traveling and transmitting driving force to wheels, and a driving force supply device as a source of the driving force,
An acquisition unit that acquires a charge rate of each of the batteries and a deterioration acceleration region that is a charge rate region in which battery deterioration is promoted;
When the driving force supply device is a supply source of the driving force, at least two of the batteries are set as adjustment batteries, and the adjustment batteries are set so that the respective charging rates are separated from the deterioration acceleration region. An adjustment control unit that moves electric power between,
A battery control device for a vehicle, comprising: The vehicle battery control device according to claim 1, wherein the driving force supply device is a generator, and supplies electric power from the generator to the traveling motor to transmit the driving force to the wheels. The driving force supply device is a power storage device, and the power from the power storage device is supplied to the traveling motor so that the driving force can be transmitted to the wheels.
A drive control unit configured to set one or more of the two or more batteries and the power storage device as a travel battery and supply the electric power of the travel battery to the motor; ,
The acquisition unit acquires a charge rate of the power storage device and a deterioration acceleration region that is a charge rate region where battery deterioration is promoted,
The adjustment control unit sets the two or more batteries excluding the traveling battery or the power storage device as an adjustment battery, and sets the charging rate between the adjustment batteries so that the charging rates are separated from the deterioration acceleration region. The battery control device for a vehicle according to claim 1, wherein the electric power is moved by the vehicle. A power supply circuit for connecting the motor and the battery for traveling;
An adjustment circuit that is provided independently of the power supply circuit and connects between the adjustment batteries;
The battery control device for a vehicle according to claim 3, comprising: A switch for switching the power supply destination of the battery to the power supply circuit and the adjustment circuit;
A converter interposed on the adjustment circuit for controlling the voltage of the adjustment battery;
The battery control device for a vehicle according to claim 4, further comprising: The drive control unit resets another travel battery when the charge rate of the travel battery enters the deterioration acceleration region from outside the deterioration acceleration region. The battery control device for a vehicle according to any one of 3 to 5. The vehicle battery control device according to any one of claims 3 to 6, wherein the adjustment battery includes an electricity storage device having a narrower deterioration acceleration region than the travel battery. The vehicle is equipped with a generator connected to the adjustment circuit,
8. The vehicle battery control device according to claim 3, wherein the adjustment control unit supplies electric power generated by the generator to a charging target in the adjustment battery. 9.

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