JP2014217179A - Vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that when a bias of salt concentration due to discharge of electricity occurs, the bias of salt concentration may not be eliminated even by charging after the discharge of electricity.SOLUTION: A vehicle has: a secondary cell (11) that outputs electricity to be converted into a kinetic energy for travelling the vehicle; an engine (26) that generates the kinetic energy for travelling the vehicle; at least one generator (MG1) that receives the output of the engine to generate electricity; a current sensor (22) that detects the current value of the secondary cell; and a controller (30) that controls discharge and charge of the secondary cell and calculates, using the detected value by the current sensor, damage amounts for estimating a deterioration state in association with a bias of salt concentration due to the discharge of the secondary cell. The controller, when receiving a signal responding to an operation by a user to discharge the secondary cell using output electricity of the generator and when an integrated quantity of the damage amounts is larger than a predetermined quantity, sets an upper limit electricity for allowing the secondary cell to be charged according to the integrated quantity.

Description

  The present invention relates to a vehicle capable of increasing the SOC of a secondary battery using the output of an engine.

  Japanese Patent Application Laid-Open No. H10-260260 describes that when high-power discharge is performed, ion bias (salt concentration bias) occurs in the electrolytic solution, which lowers the battery voltage. That is, due to the discharge of high power, the resistance value of the battery increases and the battery voltage decreases. Here, in Patent Document 1, the battery voltage is recovered by forcibly charging the battery after discharging a large amount of power.

JP 2005-245069 A

  As described in Patent Document 1, the uneven salt concentration accompanying discharge can be eliminated by charging the secondary battery (including forced charging). However, the elimination of the uneven salt concentration depends on the power (particularly the current value) during charging. Therefore, even if the battery is forcibly charged, it may not be possible to reduce the increase in resistance of the battery due to the discharge of high power. That is, depending on the power during forced charging, the increase in battery resistance may not be reduced. In order to eliminate the uneven concentration of salt, it is necessary to grasp the uneven state of salt concentration.

  The vehicle of the present invention includes a secondary battery, an engine, at least one generator, a current sensor, and a controller. The secondary battery outputs electric power converted into kinetic energy for running the vehicle, and the engine generates kinetic energy for running the vehicle. The generator receives power from the engine to generate power, and the current sensor detects the current value of the secondary battery. The controller controls charging / discharging of the secondary battery. In the vehicle of the present invention, the secondary battery is charged using the output power of the generator (hereinafter referred to as forced charging) by receiving a signal according to the user's operation while traveling.

  The controller calculates the amount of damage when charging and discharging the secondary battery. The amount of damage is a value for evaluating the deterioration state of the secondary battery, and the deterioration state here is a state in which the resistance value of the secondary battery is increased due to a bias in salt concentration due to discharge of the secondary battery. It is. Since the deviation of the salt concentration inside the secondary battery depends on the current value of the secondary battery, the amount of damage can be calculated using the detection value of the current sensor.

  The amount of damage can be calculated at a predetermined cycle, and the integrated amount of damage can be calculated each time the amount of damage is calculated. By calculating the integrated amount of the damage amount, it is possible to grasp the deterioration state associated with the uneven salt concentration due to the discharge. Here, when the integrated amount is larger than the predetermined amount, it is preferable to suppress an increase in the resistance of the secondary battery due to the uneven salt concentration. When the salt concentration unevenness due to the discharge is eliminated by forced charging, the upper limit power that permits charging of the secondary battery is set according to the integrated amount. That is, the upper limit power used in the forced charging control is set according to the integrated amount.

  As described above, the cancellation of the salt concentration bias depends on the power (particularly, the current value) during charging. Further, in order to eliminate the uneven concentration of salt, it is necessary to grasp the uneven state of the salt concentration.

  Therefore, in the present invention, the upper limit power used in the forced charge control is set according to the integrated amount (salt concentration uneven state) while calculating the integrated amount of the damage amount to grasp the uneven state of the salt concentration. ing. By performing forced charging under the upper limit power set according to the integrated amount, it becomes easier to eliminate the uneven concentration of salt due to the discharge, and it becomes easier to suppress the increase in resistance of the secondary battery due to the uneven concentration of salt. . By suppressing the increase in resistance of the secondary battery, the input / output performance of the secondary battery can be improved, and for example, drivability when the vehicle is traveling can be improved.

  When setting the upper limit power according to the integrated amount, the upper limit power can be set to a value lower than the discharge power that generates the calculated integrated amount. In order to eliminate the salt concentration unevenness by charging in the state where the salt concentration unevenness due to discharge occurs, the rate during charging (current value) should be smaller than the rate during discharging (current value). Good. Here, since the integrated amount of the damage amount changes according to the discharge state of the secondary battery, if the current integrated amount is calculated, it is possible to grasp the discharge state until the current integrated amount is reached. If the relationship between the charge rate and the discharge rate described above is taken into account after grasping this discharge state (discharge power), the upper limit power used in the forced charge control can be set.

  When the integrated amount of damage changes to a predetermined amount or less, it can be determined that the salt concentration unevenness associated with the discharge has been eliminated. For this reason, when the integrated amount is equal to or less than the predetermined amount, it is not necessary to consider the salt concentration bias accompanying discharge when setting the upper limit power during forced charging. Therefore, when the integrated amount changes below a predetermined amount, it is not possible to set the upper limit power according to the integrated amount. In this case, the upper limit power is set without considering the integrated amount. For example, the upper limit power can be set in consideration of the temperature of the secondary battery, SOC (State of Charge), and the like.

  On the other hand, when the secondary battery is in a non-energized state, the salt concentration bias is easily eliminated by diffusion of ions that contribute to the charge / discharge reaction of the secondary battery. In addition, as time elapses, ions become easier to diffuse. For this reason, when the duration when the secondary battery is in a non-energized state is longer than a predetermined time for eliminating the uneven concentration of salt, it can be determined that the uneven concentration of salt is eliminated. In this case, when setting the upper limit power during forced charging, it is not necessary to consider the salt concentration bias accompanying discharge. Therefore, when the duration time is longer than the predetermined time, the upper limit power according to the integrated amount can not be set, and the upper limit power can be set without considering the integrated amount.

  The resistance value of the secondary battery includes a resistance component that accompanies an uneven salt concentration and a resistance component that accompanies wear of the secondary battery. Here, when the resistance value of the secondary battery is equal to or less than the resistance value when the salt concentration unevenness is eliminated, it can be determined that the salt concentration unevenness is eliminated. In this case, when setting the upper limit power during forced charging, it is not necessary to consider the salt concentration bias accompanying discharge. Therefore, when the resistance value of the secondary battery is equal to or less than the resistance value when the salt concentration bias is eliminated, the upper limit power according to the integrated amount can not be set, and the integrated amount is not considered. The upper limit power can be set.

  When calculating the integrated amount of damage, only the amount of damage exceeding the reference amount can be used. Here, the reference amount can be appropriately set in consideration of the amount of damage that affects the deterioration state due to the bias in the salt concentration. The damage amount includes a damage amount that easily affects the deteriorated state and a damage amount that does not easily affect the deteriorated state. For this reason, in order to grasp the deterioration state accompanying the bias of the salt concentration using the integrated amount, only the damage amount that easily affects the deterioration state can be considered.

  In the mode in which the vehicle travels using both the engine and the secondary battery, charging / discharging of the secondary battery is controlled so that the SOC of the secondary battery changes within a predetermined range. Here, when performing forced charging, the secondary battery can be charged up to an SOC higher than the upper limit value of the predetermined range. Thus, after the forced charging is performed, the vehicle can be driven using only the output of the secondary battery until the SOC of the secondary battery is lowered to the upper limit value of the predetermined range.

  In the vehicle of the present invention, a motor / generator can be provided in addition to the generator described above. The motor / generator can generate kinetic energy for running the vehicle by receiving the output power of the secondary battery, or convert the kinetic energy generated during braking of the vehicle into electric power.

  The vehicle of the present invention can be provided with a switch that outputs a signal instructing forced charging. Here, the switch is operated by the user, and a signal instructing forced charging is output to the controller in accordance with the operation of the user. The controller can start forced charging in response to the output signal of the switch.

It is a figure which shows the structure of a battery system. It is a figure explaining the running mode of vehicles. It is a figure explaining the change range of SOC in HV driving | running | working, and the setting range of SOC when forced charging is complete | finished. It is a figure which shows the fluctuation | variation of SOC accompanying operation of a SOC recovery switch. It is a figure which shows the resistance increase rate by charging / discharging at the same rate, and the resistance increase rate by charging / discharging at a mutually different rate. It is a flowchart which shows the process of forced charge. It is a flowchart which shows the process which cancels | releases the setting of the upper limit electric power based on damage integrated amount.

  Examples of the present invention will be described below.

  FIG. 1 is a diagram illustrating a configuration of a battery system according to the present embodiment, and the battery system is mounted on a vehicle.

  The assembled battery 10 includes a plurality of unit cells 11 connected in series. As the cell 11, a secondary battery such as a nickel metal hydride battery or a lithium ion battery can be used. The number of single cells 11 can be set as appropriate based on the required output of the battery pack 10 and the like. The assembled battery 10 can also include a plurality of single cells 11 connected in parallel.

  The monitoring unit 20 detects the voltage value Vb of the assembled battery 10 or detects the voltage value Vb of each unit cell 11, and outputs the detection result to the controller 30. Here, when all the unit cells 11 constituting the assembled battery 10 are divided into a plurality of battery blocks, the monitoring unit 20 can also detect the voltage value of each battery block. Each battery block is configured by a plurality of single cells 11 connected in series, and the assembled battery 10 is configured by connecting the plurality of battery blocks in series. Here, the battery block may include a plurality of single cells 11 connected in parallel.

  The temperature sensor 21 detects the temperature Tb of the assembled battery 10 and outputs the detection result to the controller 30. Use of the plurality of temperature sensors 21 makes it easy to accurately detect the temperatures of the plurality of single cells 11 arranged at different positions. In addition, when using the several temperature sensor 21, the number of the temperature sensors 21 can be set suitably.

  A current sensor 22 is provided on the positive electrode line PL connected to the positive electrode terminal of the assembled battery 10. The current sensor 22 detects the current value (charging current or discharging current) Ib flowing through the assembled battery 10 and outputs the detection result to the controller 30. In the present embodiment, when the battery pack 10 is discharged, a positive value is used as the current value Ib detected by the current sensor 22. Further, when the battery pack 10 is being charged, a negative value is used as the current value Ib detected by the current sensor 22.

  In the present embodiment, the current sensor 22 is provided on the positive electrode line PL, but the current sensor 22 only needs to be able to detect the current value Ib flowing through the assembled battery 10, and the position where the current sensor 22 is provided can be set as appropriate. Specifically, the current sensor 22 can be provided in at least one of the positive electrode line PL and the negative electrode line NL. The negative electrode line NL is connected to the negative electrode terminal of the assembled battery 10. Here, a plurality of current sensors 22 may be provided.

  The controller 30 includes a memory 31, and the memory 31 stores various information for the controller 30 to perform predetermined processing (particularly processing described in the present embodiment). The controller 30 has a timer 32, and the timer 32 is used for time measurement. In the present embodiment, the memory 31 and the timer 32 are built in the controller 30, but at least one of the memory 31 and the timer 32 may be provided outside the controller 30.

  A system main relay SMR-B is provided in the positive electrode line PL. System main relay SMR-B is switched between on and off by receiving a control signal from controller 30. A system main relay SMR-G is provided in the negative electrode line NL. System main relay SMR-G is switched between on and off by receiving a control signal from controller 30.

  A system main relay SMR-P and a current limiting resistor R are connected in parallel to the system main relay SMR-G. System main relay SMR-P and current limiting resistor R are connected in series. System main relay SMR-P is switched between on and off by receiving a control signal from controller 30. The current limiting resistor R is used for suppressing an inrush current from flowing when the assembled battery 10 is connected to a load (specifically, an inverter 23 described later).

  The assembled battery 10 is connected to the inverter 23 via the positive electrode line PL and the negative electrode line NL. When connecting the assembled battery 10 to the inverter 23, the controller 30 first switches the system main relay SMR-B from off to on and switches the system main relay SMR-P from off to on. As a result, a current flows through the current limiting resistor R.

  Next, the controller 30 switches the system main relay SMR-G from off to on and switches the system main relay SMR-P from on to off. Thereby, the connection between the assembled battery 10 and the inverter 23 is completed, and the battery system shown in FIG. 1 is in a start-up state (Ready-On). Information about on / off of the ignition switch of the vehicle is input to the controller 30, and when the ignition switch is switched from off to on, the controller 30 activates the battery system shown in FIG.

  On the other hand, when the ignition switch is switched from on to off, the controller 30 switches the system main relays SMR-B and SMR-G from on to off. Thereby, the connection between the assembled battery 10 and the inverter 23 is cut off, and the battery system shown in FIG. 1 is in a stopped state (Ready-Off).

  The inverter 23 converts the DC power output from the assembled battery 10 into AC power, and outputs the AC power to the motor generator MG2. Motor generator MG2 receives the AC power output from inverter 23 and generates kinetic energy for running the vehicle. The motor / generator MG2 is connected to the drive wheels 24 via a reduction gear or the like, and the kinetic energy generated by the motor / generator MG2 is transmitted to the drive wheels 24. Thereby, the vehicle can be driven.

  The power split mechanism 25 transmits the power of the engine 26 to the drive wheels 24 or to the motor / generator MG1. Motor generator MG1 receives power from engine 26 to generate power. The electric power generated by the motor / generator MG <b> 1 is supplied to the motor / generator MG <b> 2 or the assembled battery 10 via the inverter 23. If the electric power generated by the motor / generator MG1 is supplied to the motor / generator MG2, the drive wheels 24 can be driven by the kinetic energy generated by the motor / generator MG2. Further, if the electric power generated by the motor / generator MG1 is supplied to the assembled battery 10, the assembled battery 10 can be charged.

  When the vehicle is decelerated or stopped, the motor / generator MG2 converts kinetic energy generated during braking of the vehicle into electric energy (AC power). The inverter 23 converts AC power generated by the motor / generator MG2 into DC power and outputs the DC power to the assembled battery 10. Thereby, the assembled battery 10 can store regenerative electric power.

  In this embodiment, the assembled battery 10 is connected to the inverter 23, but the present invention is not limited to this. Specifically, a booster circuit can be provided in the current path between the assembled battery 10 and the inverter 23. The booster circuit can boost the output voltage of the assembled battery 10 and output the boosted power to the inverter 23. Further, the booster circuit can step down the output voltage of the inverter 23 and output the lowered power to the assembled battery 10.

  A charger 27 is connected to the positive electrode line PL and the negative electrode line NL via charging lines CL1 and CL2. Charging relays Rch1 and Rch2 are provided in each of charging lines CL1 and CL2, and each charging relay Rch1 and Rch2 switches between on and off in response to a control signal from controller 30. An inlet (so-called connector) 28 is connected to the charger 27, and the inlet 28 is connected to a plug (so-called connector) installed outside the vehicle.

  The plug is connected to an external power source, and by connecting the plug to the inlet 28, power from the external power source can be supplied to the assembled battery 10 via the charger 27. Thereby, the assembled battery 10 can be charged using an external power supply. Charging the assembled battery 10 using an external power supply is referred to as external charging. The external power source is a power source installed outside the vehicle. Examples of the external power source include a commercial power source.

  When the external power supply supplies AC power, the charger 27 converts AC power from the external power supply into DC power and supplies the DC power to the assembled battery 10. In addition, when performing external charging, the charger 27 can also convert a voltage. In this embodiment, the charger 27 is mounted on the vehicle, but the charger can be installed outside the vehicle. Further, wired or wireless can be used in the path for supplying power from the external power source to the assembled battery 10. As wireless, a non-contact charging system using electromagnetic induction or resonance phenomenon can be used. A known configuration can be appropriately selected for the non-contact charging system.

  In this embodiment, external charging can be performed by turning on the system main relays SMR-B and SMR-G and turning on the charging relays Rch1 and Rch2. Here, the charging lines CL1 and CL2 can be directly connected to the positive terminal and the negative terminal of the assembled battery 10, respectively. In this case, external charging can be performed only by turning on the charging relays Rch1 and Rch2. Here, a part of charging lines CL1 and CL2 may be used together with a part of lines PL and NL.

  The battery system of the present embodiment includes two motor generators MG1 and MG2, but is not limited thereto. For example, the present invention can be applied to a system including one motor / generator. In a system including one motor / generator, the vehicle can be driven using the power of the engine while the motor / generator generates electric power. Here, for example, the power of the engine can be used to generate power from the motor / generator.

  On the other hand, in a system provided with two motors / generators, the vehicle can be driven using the power of the engine while the two motors / generators generate electric power. Here, for example, two motors / generators can generate electric power using the power of the engine. Further, it is possible to drive the vehicle using the other motor generator and the engine while generating one of the two motor generators. Here, for example, one motor / generator can be generated using the power of the engine. The other motor / generator can generate kinetic energy used to travel the vehicle using the output power of the battery pack 10.

  The SOC recovery switch 29 is mounted on the vehicle and is operated by a user (for example, a driver). The SOC recovery switch 29 is used to raise the SOC (State of Charge) of the battery pack 10, and an operation signal (ON / OFF) of the SOC recovery switch 29 is input to the controller 30. Here, the user is a person who operates the SOC recovery switch 29. The SOC is the ratio of the current charge capacity to the full charge capacity.

  When the SOC recovery switch 29 is switched from OFF to ON by a user operation, the controller 30 causes the motor / generator MG1 to generate electric power using the engine 26. The motor / generator MG1 converts the kinetic energy output from the engine 26 into electric energy, and the electric energy generated by the motor / generator MG1 is supplied to the assembled battery 10 via the inverter 23.

  Thus, the assembled battery 10 can be forcibly charged by turning on the SOC recovery switch 29. In the present embodiment, charging of the assembled battery 10 when the SOC recovery switch 29 is turned on is referred to as forced charging. Forced charging is performed when the battery system shown in FIG. 1 is in an activated state. For example, forcible charging can be performed when the battery system is in an activated state and the vehicle is stopped or while the vehicle is traveling.

  When the vehicle is stopped, for example, forced charging can be performed under a constant current. On the other hand, when forced charging is performed while the vehicle is running, a part of the power of the engine 26 is transmitted to the drive wheels 24 to drive the vehicle, and the remaining power of the engine 26 can be used for forced charging. In this case, the current value at the time of forced charging may change depending on the running state of the vehicle.

  When the SOC of the battery pack 10 reaches a predetermined value (SOC_end), forced charging can be terminated. Here, SOC_end can be set in advance, and information related to SOC_end is stored in the memory 31. The setting of SOC_end can be changed by the user or the like. In addition, as a method of estimating SOC of the assembled battery 10 (unit cell 11), a well-known method can be used suitably. For example, the SOC of the assembled battery 10 (unit cell 11) is estimated by integrating the current value Ib flowing through the assembled battery 10 (unit cell 11), or the open voltage of the assembled battery 10 (unit cell 11) is measured. Thus, it is possible to estimate the SOC of the battery pack 10 (unit cell 11).

  When charging / discharging of the assembled battery 10 is controlled, an upper limit power Win_lim that allows charging and an upper limit power Wout_lim that allows discharging are set. Here, the controller 30 controls the charging of the assembled battery 10 so that the charging power of the assembled battery 10 does not exceed the upper limit power Win_lim. Further, the controller 30 controls the discharge of the assembled battery 10 so that the discharged power of the assembled battery 10 does not exceed the upper limit power Wout_lim. Even when forced charging is performed, charging of the battery pack 10 is controlled based on the upper limit power Win_lim.

  The upper limit powers Win_lim and Wout_lim can be set according to, for example, the temperature Tb and SOC of the assembled battery 10. If the correspondence between the upper limit power Win_lim and at least one of the battery temperature Tb and the SOC is obtained in advance by experiments or the like, the upper limit power Win_lim can be calculated by obtaining the battery temperature Tb and the SOC. Similarly, if the correspondence relationship between the upper limit power Wout_lim and at least one of the battery temperature Tb and the SOC is obtained in advance by experiments or the like, the upper limit power Wout_lim can be calculated by obtaining the battery temperature Tb and the SOC. .

  The correspondence relationship described above can be expressed as a map or a function, and information regarding the correspondence relationship can be stored in the memory 31. The correspondence described above can be set as appropriate based on the viewpoint of protecting the unit cell 11 and the viewpoint of securing the input / output performance of the unit cell 11. The protection of the cell 11 includes suppressing overcharge and overdischarge, and suppressing abnormal heat generation of the cell 11.

  In this embodiment, the SOC recovery switch 29 is mounted on the vehicle, but the present invention is not limited to this. Specifically, forced charging of the assembled battery 10 can be instructed from the outside of the vehicle. For example, when the user operates a terminal (such as a portable terminal) provided separately from the vehicle, a signal instructing forced charging can be input to the controller 30. In this case, the receiver which receives the signal from a terminal can be mounted in the vehicle. In addition, a signal for instructing forced charging can be transmitted to the controller 30 via wired or wireless.

  In the vehicle of the present embodiment, EV (Electric Vehicle) traveling and HV (Hybrid Vehicle) traveling can be performed. The EV traveling is to travel the vehicle using only the output of the assembled battery 10. The HV running is to run the vehicle using the assembled battery 10 and the engine 26 in combination.

  Specifically, as shown in FIG. 2, EV traveling can be performed until the SOC of the battery pack 10 decreases to a predetermined value SOC_hv. In FIG. 2, the vertical axis represents the SOC of the battery pack 10, and the horizontal axis represents time. In EV traveling, since the vehicle is driven using only the output of the assembled battery 10, the SOC of the assembled battery 10 decreases as the vehicle travels.

  When the SOC of the battery pack 10 reaches a predetermined value SOC_hv, it is possible to switch from EV traveling to HV traveling. In HV traveling, charging / discharging of the assembled battery 10 is controlled so that the SOC of the assembled battery 10 changes along a predetermined value SOC_hv. Here, the predetermined value SOC_hv can be set as appropriate. As the predetermined value SOC_hv is decreased, the travel distance by EV travel can be extended.

  When the SOC of the battery pack 10 is lower than the predetermined value SOC_hv during HV traveling, the discharge of the battery pack 10 is suppressed and the battery pack 10 is actively charged. Here, the assembled battery 10 can be charged by using the power of the engine 26. On the other hand, when the SOC of the assembled battery 10 rises above the predetermined value SOC_hv, charging of the assembled battery 10 is suppressed and the assembled battery 10 is actively discharged. Thereby, SOC of the assembled battery 10 can be changed along predetermined value SOC_hv.

  The SOC (SOC_end) at the time of terminating the forced charging is set to a value higher than the upper limit value of the range in which the SOC of the assembled battery 10 can change during HV traveling. FIG. 3 shows the relationship between the SOC fluctuation range in HV traveling and the SOC_end setting range. In FIG. 3, the vertical axis represents the SOC of the battery pack 10, and the horizontal axis represents time. The SOC_hv shown in FIG. 3 corresponds to the SOC_hv shown in FIG. In HV traveling, SOC_max and SOC_min are set based on SOC_hv.

  SOC_max is an SOC (upper limit value) higher than SOC_hv, and SOC_min is an SOC (lower limit value) lower than SOC_hv. In HV traveling, when the SOC of the assembled battery 10 reaches SOC_max, the assembled battery 10 is not charged and the assembled battery 10 is positively discharged. On the other hand, when the SOC of the assembled battery 10 reaches SOC_min, the assembled battery 10 is not discharged, and the assembled battery 10 is actively charged.

  Thereby, in HV traveling, as shown in FIG. 3, the SOC of the battery pack 10 changes along the SOC_hv within the range of SOC_max and SOC_min. Here, SOC_end when forced charging ends is set to a value higher than SOC_max. By setting the SOC_end in this manner, it is possible to give priority to the EV traveling instead of the HV traveling after the forced charging is performed by operating the SOC recovery switch 29. By prioritizing EV travel, the time for EV travel can be extended. SOC_end can be set as appropriate within a range higher than SOC_max.

  In the present embodiment, by operating the SOC recovery switch 29, the SOC of the battery pack 10 can be changed as shown in FIG. In FIG. 4, the horizontal axis is time, and the vertical axis is the SOC of the battery pack 10. The SOC behavior shown in FIG. 4 is a change in the SOC while the vehicle is running. If the SOC recovery switch 29 is operated during EV traveling, forced charging is started and the SOC of the battery pack 10 increases. Then, when the SOC of the battery pack 10 reaches SOC_end, forced charging ends, and EV driving can be performed after forced charging ends.

  As shown in FIG. 4, by operating the SOC recovery switch 29, EV running (discharge of the assembled battery 10) and forced charging can be performed alternately. When EV traveling is performed, the concentration of salt in the cell 11 is biased according to the current value (high rate) when the battery pack 10 (cell 11) is discharged. This uneven concentration of salt is an uneven concentration of salt in the electrolyte solution of the battery cell 11.

  When the ions move between the positive electrode and the negative electrode of the unit cell 11, the unit cell 11 is charged / discharged. However, when discharge at a high rate is performed, an uneven salt concentration occurs on the discharge side. Due to this uneven concentration of salt, the resistance value (internal resistance) of the unit cell 11 is increased, and the deterioration of the unit cell 11 is advanced. Here, the deterioration of the unit cell 11 due to the uneven salt concentration is called high-rate deterioration.

  High-rate degradation can be evaluated using the damage amount D_dam_dc. Here, the damage amount D_dam_dc can be calculated at a predetermined period Δt based on the following formula (1). The controller 30 calculates the damage amount D_dam_dc.

  In the above equation (1), t represents time, D_dam_dc [t + Δt] is the amount of damage calculated this time, and D_dam_dc [t] is the amount of damage calculated last time. As shown in the above equation (1), the current damage amount D_dam_dc [t + Δt] is calculated based on the previous damage amount D_dam_dc [t]. The damage amount D_dam_dc [0] as an initial value can be set to “0”, for example.

  The second term on the right side shown in the above equation (1) is a decrease term of the damage amount D_dam_dc, and indicates a component when the bias of the salt concentration is alleviated. The third term on the right side shown in the above equation (1) is an increase term of the damage amount D_dam_dc, and indicates a component when a salt concentration bias occurs. In this way, by calculating the current damage amount D_dam_dc in consideration of the decrease term and the increase term, the change (increase / decrease) in the salt concentration bias that is considered to be the cause of the high rate deterioration is appropriately reflected in the damage amount D_dam_dc. be able to. Thereby, it can be grasped | ascertained how close the cell 11 is in the state where high-rate degradation arises based on damage amount D_dam_dc.

  The bias in salt concentration is alleviated in accordance with the diffusion of ions with the passage of time Δt, so the forgetting factor α is set in the above equation (1). The forgetting factor α is a factor corresponding to the diffusion rate of ions in the electrolytic solution of the unit cell 11, and the forgetting factor α increases as the diffusion rate increases. The value of “α × Δt” is set within a range of 0 to 1. As the value of “α × Δt” approaches “1”, the value of the decrease term of the damage amount D_dam_dc decreases. Here, the larger the value of the forgetting factor α or the longer the time Δt, the closer the value of “α × Δt” approaches “1”.

  Since the forgetting factor α depends on the SOC and the temperature Tb of the unit cell 11, the forgetting factor α can be set according to the SOC and the battery temperature Tb. Specifically, the correspondence relationship between the forgetting factor α and at least one of the SOC and the battery temperature Tb can be obtained in advance by an experiment or the like. When obtaining the correspondence relationship between the forgetting factor α, the SOC, and the battery temperature Tb, for example, if the battery temperature is the same, the forgetting factor α may increase as the SOC of the unit cell 11 increases. Further, if the SOC of the unit cells 11 is the same, the forgetting factor α may increase as the battery temperature increases.

  The correspondence relationship between the forgetting factor α and at least one of the SOC and the battery temperature Tb can be expressed as a map or a function, and information regarding this correspondence relationship can be stored in the memory 31. If this correspondence is used, the forgetting factor α can be set by acquiring the SOC and the battery temperature Tb.

  In the above equation (1), β is a current coefficient, and c0_pow_dc is a limit threshold. Since the current coefficient β and the limit threshold c0_pow_dc depend on the SOC and the temperature Tb of the single battery 11, the current coefficient β and the limit threshold c0_pow_dc can be set according to the SOC and the battery temperature Tb. Specifically, if the correspondence relationship (map or function) between the current coefficient β and at least one of the SOC and the battery temperature Tb is obtained in advance by an experiment or the like, the current or current can be obtained by obtaining the SOC or the battery temperature Tb. The coefficient β can be calculated.

  Similarly, if a correspondence relationship (map or function) between the limit threshold c0_pow_dc and at least one of the SOC and the battery temperature Tb is obtained in advance by experiments or the like, the limit threshold c0_pow_dc is obtained by acquiring the SOC and the battery temperature Tb. Can be calculated. Information about the correspondence relationship for calculating the current coefficient β and the limit threshold value c0_pow_dc can be stored in the memory 31. When obtaining the correspondence relationship between the limit threshold c0_pow_dc, the SOC, and the battery temperature Tb, for example, if the battery temperature Tb is the same, the limit threshold c0_pow_dc may increase as the SOC of the unit cell 11 increases. Further, if the SOCs of the single cells 11 are the same, the limit threshold c0_pow_dc may increase as the battery temperature Tb increases.

  Ib shown in the above formula (1) is the value of the current flowing through the unit cell 11. A value detected by the current sensor 22 is used as the current value Ib. Here, when the assembled battery 10 is discharged, the current value Ib becomes a positive value, and when the assembled battery 10 is charged, the current value Ib becomes a negative value. As the current value Ib increases or the time Δt increases, the value of the third term (increase term) on the right side shown in the above equation (1) increases.

  When grasping the progress state of the high rate deterioration, the integrated value (damage integrated amount) Dam_dc of the damage amount D_dam_dc is used. The damage integrated amount Dam_dc can be calculated based on the following formula (2).

  In the above equation (2), Dam_dc [t + Δt] is the current damage integrated amount, and Dam_dc [t] is the previous damage integrated amount. As shown in the above equation (2), the current damage integrated amount Dam_dc [t + Δt] is calculated in consideration of the previous damage integrated amount Dam_dc [t].

  Γ_dc shown in the above equation (2) is an attenuation coefficient, and is a value smaller than “1”. Due to the diffusion of ions over time, the uneven salt concentration is alleviated, so when calculating the current damage integrated amount Dam_dc, the previous damage integrated amount Dam_dc may decrease. Therefore, in consideration of this point, the attenuation coefficient γ_dc is set. The attenuation coefficient γ_dc can be set in advance, and information regarding the attenuation coefficient γ_dc can be stored in the memory 31.

  Η shown in the above equation (2) is a correction coefficient. The correction coefficient η can be set as appropriate, and information regarding the correction coefficient η can be stored in the memory 31. Further, D_dam_dc shown in the above equation (2) is the current damage amount calculated by the above equation (1). In this embodiment, the damage amount D_dam_dc is calculated at a predetermined period Δt, but the damage integrated amount Dam_dc is calculated using only the damage amount D_dam_dc that satisfies the predetermined condition.

  Specifically, a reference amount D_dam_th related to the damage amount D_dam_dc is set, and the damage integrated amount Dam_dc is calculated using the damage amount D_dam_dc that is equal to or greater than the reference amount D_dam_th. Here, the reference amount D_dam_th is used to specify the damage amount D_dam_dc that easily affects the high-rate deterioration, and the reference amount D_dam_th can be appropriately set in consideration of this point. Information regarding the reference amount D_dam_th can be stored in the memory 31. Note that the damage integrated amount Dam_dc can also be calculated using all of the calculated damage amounts D_dam_dc.

  It is known that the salt concentration bias accompanying the discharge of the unit cell 11 can be alleviated by charging the unit cell 11. In other words, since the state of salt concentration unevenness accompanying discharge and the state of salt concentration unevenness accompanying charging are contradictory, the salt concentration unevenness accompanying charging is generated by generating the salt concentration unevenness accompanying charging. Can be relaxed. However, as shown in FIG. 4, when the charging of the single cell 11 is continued after the discharge of the single cell 11 is continued, it becomes difficult to alleviate the uneven salt concentration accompanying the discharge, and the resistance of the single cell 11 increases. It was found that it was not possible to reduce

  FIG. 5 shows a change in the rate of increase in resistance of the unit cell 11 when continuous charging is performed after continuous discharging. In FIG. 5, the horizontal axis represents the number of cycles, and the vertical axis represents the resistance increase rate. The number of cycles is the number of cycles when the process of performing continuous charge after performing continuous discharge is defined as one cycle. The resistance increase rate is expressed by a ratio (100 × Rnow / Rini) between the current resistance value (internal resistance) Rnow of the unit cell 11 and the resistance value Rini when the unit cell 11 is in the initial state. The initial state is a state in which the unit cell 11 has not deteriorated, and can be, for example, a state immediately after the unit cell 11 is manufactured. The resistance value Rini can be obtained in advance by experiments or the like.

  As the deterioration of the unit cell 11 progresses, the resistance value Rnow of the unit cell 11 increases, so that the resistance increase rate also increases. The dotted line shown in FIG. 5 shows the change in resistance increase rate when charging / discharging is performed at the same rate. As indicated by the dotted line in FIG. 5, even if the battery is continuously discharged at a predetermined rate (the same rate as during discharging) after being discharged at a predetermined rate, the rate of increase in resistance of the unit cell 11 is increased. . This means that the uneven concentration of salt accompanying discharge is not alleviated by charge after discharge.

  On the other hand, the solid line shown in FIG. 5 shows the change in the resistance increase rate when charging and discharging are performed at different rates. Specifically, in the case where continuous charging is performed after continuous discharging, the rate during charging is set lower than the rate during discharging. In this case, as indicated by the solid line in FIG. 5, the rate of increase in resistance of the single battery 11 is difficult to increase. As can be seen from the experimental results shown in FIG. 5, when continuous charging is performed after continuous discharging, the increase in resistance of the unit cell 11 is suppressed by making the rate during charging lower than the rate during discharging. can do.

  If the increase in resistance of the single battery 11 (the assembled battery 10) is suppressed, the input / output performance of the single battery 11 (the assembled battery 10) can be improved. Accordingly, when the vehicle is driven using the output of the assembled battery 10, drivability during driving can be improved. In addition, when the vehicle is braked, the regenerative power can be efficiently stored in the assembled battery 10.

  In this embodiment, the SOC of the battery pack 10 may change as a result of the operation of the SOC recovery switch 29, as shown in FIG. Here, as can be seen from the experimental results shown in FIG. 5, even if the charging rate in forced charging is equal to the discharging rate of the assembled battery 10 in EV traveling, the resistance increases due to the uneven salt concentration during discharging (that is, High rate deterioration) cannot be suppressed. In the present embodiment, in consideration of the experimental results shown in FIG. 5, the charging rate in forced charging is set lower than the discharging rate of the assembled battery 10 in EV traveling.

  Hereinafter, the process for suppressing the resistance increase (high-rate degradation) of the unit cell 11 due to the uneven salt concentration during discharge will be described with reference to the flowchart shown in FIG. The process shown in FIG. 6 is started when the SOC recovery switch 29 is switched from OFF to ON, and is executed by the controller 30.

  In step S101, the controller 30 confirms that the SOC recovery switch 29 is on. In step S102, the controller 30 determines whether or not the current integrated damage amount Dam_dc is equal to or less than a predetermined amount Dam_th. As described above, the controller 30 calculates the damage amount D_dam_dc in the predetermined period Δt, and calculates the damage integrated amount Dam_dc based on the damage amount D_dam_dc. Therefore, the controller 30 can grasp the damage integrated amount Dam_dc when the SOC recovery switch 29 is turned on, and compares the damage integrated amount Dam_dc with the predetermined amount Dam_th.

  The predetermined amount Dam_th is a value set in advance based on the viewpoint of suppressing an increase in resistance of the unit cell 11 due to a deviation in salt concentration during discharge. The predetermined amount Dam_th can be set as appropriate, and information on the predetermined amount Dam_th can be stored in the memory 31. When the damage integrated amount Dam_dc is larger than the predetermined amount Dam_th, the controller 30 determines that it is necessary to suppress the increase in resistance of the unit cell 11, and performs the process of step S103.

  On the other hand, when the damage integrated amount Dam_dc is equal to or less than the predetermined amount Dam_th, the controller 30 determines that it is not necessary to suppress the increase in resistance of the unit cell 11, and performs the process of step S104. In steps S103 and S104, the controller 30 sets an upper limit power Win_lim for forced charging. Here, in the processes of steps S103 and S104, as described below, the setting method of the upper limit power Win_lim is different.

  In the process of step S103, the upper limit power Win_lim is set based on the damage integrated amount Dam_dc. Specifically, if the correspondence (map or function) between the damage integrated amount Dam_dc and the upper limit power Win_lim is obtained in advance by experiments or the like, the upper limit power Win_lim can be calculated by calculating the damage integrated amount Dam_dc. . Information regarding the correspondence between the damage integrated amount Dam_dc and the upper limit power Win_lim can be stored in the memory 31.

  In the process of step S104, the upper limit power Win_lim corresponding to the damage integrated amount Dam_dc can be set in consideration of the experimental result shown in FIG. That is, by considering the experimental results shown in FIG. 5, the upper limit power Win_lim that can reduce the damage integrated amount Dam_dc can be obtained in advance by experiments or the like.

  For example, the relationship between the damage integrated amount Dam_dc and the discharge power Wout when the damage integrated amount Dam_dc is generated can be obtained by experiments or the like. Considering the experimental results shown in FIG. 5, since the charging rate may be lower than the discharging rate, the upper limit power Win_lim may be lower than the discharging power Wout when the damage integrated amount Dam_dc is generated. .

  In the present embodiment, the current value Ib at the time of discharging becomes a positive value and the current value Ib at the time of charging becomes a negative value, so that the discharging power Wout becomes a positive value and the charging power Win becomes a negative value. For this reason, the absolute value of the upper limit power Win_lim only needs to be lower than the discharge power Wout. Here, if the upper limit power (absolute value) Win_lim is lower than the discharge power Wout, it is possible to suppress an increase in resistance due to a deviation in salt concentration during discharge. For this reason, the upper limit power Win_lim can be appropriately set within a range lower than the discharge power Wout when the damage integrated amount Dam_dc is generated.

  Here, if the upper limit power Win_lim is too low, the amount of increase in the SOC with respect to a predetermined time in the forced charging becomes small, and the time until the forced charging is ended tends to be long. For this reason, it is preferable to set the upper limit power Win_lim in consideration of the time until the forced charging is terminated.

  In the process of step S104, the upper limit power Win_lim is set without considering the damage integrated amount Dam_dc. Specifically, the upper limit power Win_lim can be set based on the SOC and the temperature Tb of the unit cell 11 as described above.

  In step S105, the controller 30 starts forced charging. When the forced charging is performed, the charging of the single battery 11 (the assembled battery 10) is controlled based on the upper limit power Win_lim set in the processes of steps S103 and S104. Moreover, the SOC of the single battery 11 (the assembled battery 10) increases by starting the forced charging.

  In step S106, the controller 30 determines whether or not the SOC of the current single battery 11 (the assembled battery 10) is equal to or higher than SOC_end. After starting the forced charging, the controller 30 can compare the current SOC and SOC_end by continuing to estimate the SOC of the single battery 11 (the assembled battery 10). The controller 30 continues the forced charging until the current SOC becomes equal to or higher than SOC_end. On the other hand, when the current SOC becomes equal to or higher than SOC_end, the controller 30 ends the forced charging in step S107.

  In the process of step S106, the SOC and SOC_end of the unit cell 11 can be compared, and the SOC and SOC_end of the assembled battery 10 can also be compared. Here, when the SOC and SOC_end of the unit cells 11 are compared, if the SOC of the plurality of unit cells 11 varies, it is preferable to compare the SOC of the highest unit cell 11 with the SOC_end. Thereby, when performing a forced charge, it can suppress that the cell 11 with the highest SOC will be in an overcharge state.

  In the process of step S106, it is determined whether or not the current SOC is equal to or higher than SOC_end. However, the present invention is not limited to this. For example, based on the voltage value Vb of the single battery 11 (or the assembled battery 10), it can be determined whether or not to terminate forced charging. Specifically, forced charging can be terminated when the current voltage value Vb is equal to or higher than the end voltage value for terminating forced charging. The end voltage value can be set as in the case of setting SOC_end.

  When the current voltage value Vb is lower than the end voltage value, forced charging can be continued. As the voltage value Vb here, OCV (Open Circuit Voltage) or CCV (Closed Circuit Voltage) can be used.

  In the present embodiment, when the damage integrated amount Dam_dc is larger than the predetermined amount Dam_th, the upper limit power Win_lim at the time of charging is set based on the damage integrated amount Dam_dc. In addition to this, the upper limit power Wout_lim at the time of discharging is set. Can be set. When the damage integrated amount Dam_dc is larger than the predetermined amount Dam_th, it is necessary to suppress a deviation in salt concentration due to discharge. That is, it is necessary to limit the discharge of the single battery 11 (the assembled battery 10) in order to suppress the progression of the salt concentration bias due to the discharge.

  Specifically, when the damage integrated amount Dam_dc is larger than the predetermined amount Dam_th, the reference upper limit power Wout_lim can be corrected according to the difference between the damage integrated amount Dam_dc and the predetermined amount Dam_th. Here, as the difference between the damage integrated amount Dam_dc and the predetermined amount Dam_th increases, the correction amount (the amount by which the power is reduced) of the upper limit power Wout_lim can be increased. As the reference upper limit power Wout_lim, for example, a value set from the SOC of the unit cell 11 or the temperature Tb can be used.

  In the present embodiment, the correspondence between the damage integrated amount Dam_dc and the upper limit power Win_lim is obtained in advance, and the upper limit power Win_lim corresponding to the calculated damage integrated amount Dam_dc is set, but this is not restrictive. For example, a past discharge history until the current integrated damage amount Dam_dc is acquired, and the upper limit power Win_lim can be set based on the discharge history.

  Specifically, when the damage integrated amount Dam_dc is larger than the predetermined amount Dam_th, a discharge history until the damage integrated amount Dam_dc is calculated is acquired, and an upper limit power Win_lim corresponding to the discharge history is set. be able to. Here, as the discharge history, for example, an average current value can be used. In this case, the upper limit power Win_lim can be set so that forced charging is performed with a current value smaller than the average current value during discharging.

  After the upper limit power Win_lim is set based on the damage integrated amount Dam_dc, it is possible to cancel the setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc after confirming that the damage integrated amount Dam_dc is equal to or less than the predetermined amount Dam_th. it can. In other words, when the damage integrated amount Dam_dc is equal to or less than the predetermined amount Dam_th, the upper limit power Win_lim based on the damage integrated amount Dam_dc is not set. In this case, the upper limit power Win_lim can be set according to the SOC and the temperature Tb of the cell 11 as in the process of step S104.

  When the damage integrated amount Dam_dc is larger than the predetermined amount Dam_th, the upper limit power Win_lim based on the damage integrated amount Dam_dc remains set. When the damage integrated amount Dam_dc is larger than the predetermined amount Dam_th, the bias of the salt concentration at the time of discharging has not been eliminated. Therefore, in order to suppress the high rate deterioration, the upper limit power Win_lim is set to a value corresponding to the damage integrated amount Dam_dc. It is preferable to keep it.

  On the other hand, the setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc can be canceled in consideration of the time (left time) t_rest when the cell 11 is left without being charged / discharged. Here, the leaving time t_rest is a continuation time when the unit cell 11 is in a non-energized state, and can be measured using the timer 32.

  If the unit cell 11 is left without being charged / discharged, the diffusion of ions is promoted, and the deviation of the salt concentration at the time of discharge changes in the relaxation direction. Here, if the time t_th at which the salt concentration unevenness is eliminated (referred to as the elimination time) is obtained in advance by experiments or the like, the neglected state of the salt concentration is grasped by comparing the leaving time t_rest and the elimination time t_th. can do. The elimination time t_th can be, for example, the maximum time that can eliminate the uneven concentration of salt.

  If the leaving time t_rest is longer than the elimination time t_th, it can be determined that the salt concentration bias has been eliminated, and there is no need to set the upper limit power Win_lim based on the integrated damage amount Dam_dc. That is, when the leaving time t_rest is longer than the elimination time t_th, the setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc can be canceled. In other words, when the leaving time t_rest is longer than the elimination time t_th, the upper limit power Win_lim based on the damage integrated amount Dam_dc is not set. In this case, the upper limit power Win_lim can be set based on the SOC, the temperature Tb, and the like of the unit cell 11 as in the process of step S104.

  If the neglected time t_rest is shorter than the elimination time t_th, the salt concentration unevenness is not eliminated, so it is necessary to set the upper limit power Win_lim based on the damage integrated amount Dam_dc. That is, when the leaving time t_rest is longer than the elimination time t_th, the upper limit power Win_lim based on the damage integrated amount Dam_dc remains set.

  On the other hand, in consideration of the resistance value Rb of the unit cell 11, the setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc can be canceled. Here, the resistance value Rb of the unit cell 11 can be calculated from the current value Ib and the voltage value Vb of the unit cell 11, for example. Specifically, the current value Ib and the voltage value Vb are detected while the cell 11 is being charged / discharged, and the detected value (the current value Ib and the voltage value is displayed in the coordinate system having the current value and the voltage value as coordinate axes. Plot (Vb relationship). If a straight line that approximates a plurality of plots is calculated, the slope of the approximate straight line can be used as the resistance value Rb of the unit cell 11.

  The resistance value Rb of the unit cell 11 includes a resistance component accompanying high-rate deterioration and a resistance component accompanying wear deterioration. Here, the resistance component accompanying wear deterioration is a component that increases the resistance value Rb of the unit cell 11 as the material constituting the unit cell 11 deteriorates with time. If the resistance value Rb of the unit cell 11 is grasped, it can be grasped whether or not the high-rate deterioration has been eliminated.

  For example, by setting a predetermined value (value related to the resistance value) Rth in consideration of wear deterioration and confirming that the current resistance value Rb of the unit cell 11 is equal to or less than the predetermined value Rth, the high-rate deterioration is eliminated. Can be confirmed. Here, the predetermined value Rth can be a resistance value corresponding to wear deterioration or a value higher than a resistance value corresponding to wear deterioration. Since the wear deterioration is likely to proceed with the passage of time, the predetermined value Rth can be changed according to the elapsed time. The elapsed time is the time from when the unit cell 11 is used for the first time until the present time, and can be measured using the timer 32.

  If the resistance value Rb is equal to or less than the predetermined value Rth, it can be determined that the high-rate deterioration has been eliminated, and there is no need to set the upper limit power Win_lim based on the damage integrated amount Dam_dc. That is, when the resistance value Rb is equal to or smaller than the predetermined value Rth, the setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc can be canceled. In other words, when the resistance value Rb is equal to or less than the predetermined value Rth, the upper limit power Win_lim based on the damage integrated amount Dam_dc is not set. In this case, the upper limit power Win_lim can be set based on the SOC, the temperature Tb, and the like of the unit cell 11 as in the process of step S104.

  If the resistance value Rb is higher than the predetermined value Rth, it can be determined that the high-rate deterioration has not been eliminated, and it is necessary to set the upper limit power Win_lim based on the damage integrated amount Dam_dc. That is, when the resistance value Rb is higher than the predetermined value Rth, the upper limit power Win_lim based on the damage integrated amount Dam_dc remains set.

  When canceling the setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc, among the comparison of the damage integrated amount Dam_dc and the predetermined amount Dam_th, the comparison of the standing time t_rest and the elimination time t_th, and the comparison of the resistance value Rb and the predetermined value Rth At least one can be done. Here, when performing a plurality of comparisons, the setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc can be canceled only when all the conditions in these comparisons are satisfied.

  For example, when the damage integrated amount Dam_dc and the predetermined amount Dam_th are compared with the leaving time and the elimination time, the damage integrated amount Dam_dc is equal to or less than the predetermined amount Dam_th and the leaving time is longer than the elimination time. The setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc can be canceled.

  FIG. 7 is a flowchart showing a process of canceling the setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc. The processing shown in FIG. 7 is performed after the upper limit power Win_lim is set based on the damage integrated amount Dam_dc, and is executed by the controller 30.

  In step S201, the controller 30 determines whether or not the damage integrated amount Dam_dc is equal to or less than a predetermined amount Dam_th. Further, the controller 30 measures the leaving time t_rest, and determines whether or not the leaving time t_rest is equal to or longer than the elimination time t_th. Further, the controller 30 calculates the resistance value Rb of the unit cell 11 and determines whether or not the resistance value Rb is equal to or less than a predetermined value Rth.

  Here, in the process of step S201, the damage integrated amount Dam_dc, the standing time t_rest, and the resistance value Rb are considered, but at least one of these can be considered. When the damage integrated amount Dam_dc is less than or equal to the predetermined amount Dam_th, when the leaving time t_rest is less than or equal to the elimination time t_th, and when the resistance value Rb is less than or equal to the predetermined value Rth, the controller 30 performs the process of step S202.

  On the other hand, when the damage integrated amount Dam_dc is larger than the predetermined amount Dam_th, when the leaving time t_rest is shorter than the elimination time t_th, when the resistance value Rb is higher than the predetermined value Rth, the controller 30 ends the processing shown in FIG. To do. In this case, the upper limit power Win_lim set based on the damage integrated amount Dam_dc is maintained. And charging of the cell 11 is controlled based on this upper limit electric power Win_lim.

  In step S202, the controller 30 cancels the setting of the upper limit power Win_lim based on the damage integrated amount Dam_dc. In this case, the controller 30 sets the upper limit power Win_lim without considering the damage integrated amount Dam_dc. For example, the controller 30 can set the upper limit power Win_lim based on the SOC and the temperature Tb of the unit cell 11.

10: assembled battery, 11: single cell, 20: monitoring unit, 21: temperature sensor,
22: current sensor, 23: inverter, MG1, MG2: motor / generator,
24: drive wheel, 25: power split mechanism, 26: engine, 27: charger,
28: Inlet, 30: Controller, 31: Memory, 32: Timer,
PL: positive line, NL: negative line, CL1, CL2: charge line,
SMR-B, SMR-G, SMR-P: System main relay,
R: current limiting resistor, Rch1, Rch2: charging relay

Claims (9)

A secondary battery that outputs electric power converted into kinetic energy for running the vehicle;
An engine for generating kinetic energy for running the vehicle;
At least one generator for generating power in response to the output of the engine;
A current sensor for detecting a current value of the secondary battery;
A controller that controls charging / discharging of the secondary battery, and calculates a damage amount for evaluating a deterioration state due to a deviation in salt concentration due to discharge of the secondary battery, using a detection value of the current sensor; Have
The controller receives a signal according to a user operation while the vehicle is running and charges the secondary battery using the output power of the generator, and the integrated amount of the damage amount is A vehicle characterized by setting an upper limit power allowing charging of the secondary battery according to the integrated amount when larger than a predetermined amount.   2. The controller according to claim 1, wherein when the upper limit power corresponding to the integrated amount is set, the controller sets the upper limit power to a value lower than a discharge power that generates the calculated integrated amount. Vehicle.   3. The vehicle according to claim 1, wherein the controller does not set the upper limit power according to the integrated amount when the integrated amount changes to the predetermined amount or less.   The controller does not set the upper limit power according to the integrated amount when a duration time when the secondary battery is in a non-energized state is longer than a predetermined time for eliminating the salt concentration bias. The vehicle according to any one of claims 1 to 3.   The controller does not set the upper limit power according to the integrated amount when a resistance value of the secondary battery is equal to or less than a resistance value when the unevenness of the salt concentration is eliminated. The vehicle according to any one of claims 1 to 4.   The vehicle according to any one of claims 1 to 5, wherein the integrated amount is an amount obtained by integrating the damage amount exceeding a reference amount. The controller is
In the mode in which the vehicle is driven by using the engine and the secondary battery together, the charge / discharge of the secondary battery is controlled so that the SOC of the secondary battery changes within a predetermined range;
When charging the secondary battery using the output power of the generator, the secondary battery is charged to an SOC higher than the upper limit value of the predetermined range.
The vehicle according to any one of claims 1 to 6, characterized in that:   2. A motor generator that receives the output power of the secondary battery and generates kinetic energy for running the vehicle, and converts the kinetic energy generated during braking of the vehicle into electric power. The vehicle according to any one of 7 to 7.   9. The switch according to claim 1, further comprising a switch that outputs a signal instructing charging of the secondary battery using output power of the generator in accordance with an operation of the user. vehicle.