JP6464957B2 - Battery evaluation device - Google Patents

Description

  The present invention relates to a battery evaluation apparatus.

  Cars equipped with batteries that store energy for running, such as electric cars and plug-in hybrid cars, are beginning to become popular. Such a battery has a lifetime because it deteriorates with use.

  Japanese Patent Laying-Open No. 2008-126788 discloses a vehicle battery life determination apparatus. The determination device includes a battery history determination unit, a battery information storage unit, and a battery life determination unit. The battery history determination unit determines the travel distance of the vehicle. The battery information storage unit stores data related to the relationship between the travel distance of the vehicle and the degree of battery deterioration, measured from the vehicle travel test. The battery life determination unit determines the battery life based on the relationship between the state of the battery and the battery usage history, the state of the battery stored in the battery information storage unit, the battery usage history, and the degree of battery deterioration. At that time, the battery life determination unit estimates the degree of battery deterioration from the travel distance of the vehicle determined by the battery history determination unit.

JP 2008-126788 A

  In the vehicle battery life determination device disclosed in the above document, as a result of calculating the battery life, the battery deterioration degree is set to 1.0 when there is no battery deterioration, and the battery needs to be replaced by 0.0. In this case, it is expressed by a numerical value in the meantime, and the final battery life is displayed in months.

  However, since the battery life varies depending on the frequency of use of the vehicle, the driving course, and the acceleration / deceleration conditions, even if the battery life is indicated to the user in numerical values or monthly periods, it may not match the actual life. Conceivable. Moreover, it is difficult for the user to grasp the lifetime only by notifying with a numerical value or a period.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a battery evaluation device that allows the user to easily recognize the battery life.

  In summary, the present invention is an evaluation device for evaluating a battery mounted on a vehicle, and after discharging the battery, discharges from a battery having a specified remaining capacity to a remaining capacity of a control lower limit value. Then, the user is informed of information relating to the travelable distance when traveling on a travel course designated by the user based on the amount of discharged electric power.

  According to the above evaluation apparatus, the user can know the change in the battery performance as the travelable distance in the course of daily travel, and thus can intuitively grasp the degree of deterioration of the battery.

  Preferably, the evaluation device charges and discharges the battery using a power supply device arranged at a vehicle dealer.

  If the power supply device is located at the dealer, charge / discharge control that is finer than that of an on-vehicle electric load or external charger is possible, and if an abnormality occurs during refresh processing or charge / discharge processing, it should be identified immediately. it can. In particular, when a battery failure is discovered, it is possible to respond quickly.

  According to the present invention, it is possible to notify the user of the battery life in an easy-to-understand manner when the user uses an everyday vehicle.

It is a figure for demonstrating the connection of the battery evaluation apparatus which concerns on embodiment of this invention, and a vehicle. It is a figure for demonstrating the structure and connection relation of the battery evaluation apparatus. It is a main flowchart of the process which evaluates the lifetime of a battery. It is a flowchart for demonstrating the detail of a refresh process. It is a figure for demonstrating the reference | standard driving | running | working course of battery evaluation. It is an example which shows the evaluation result of a battery by power consumption. It is a 1st example which shows the evaluation result of a battery by EV travel distance. It is a 2nd example which shows the evaluation result of a battery by EV travel distance. It is an example of the screen which showed transition of fuel consumption. It is the figure which showed the structure of the modification.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a diagram for explaining connection between a battery evaluation apparatus and a vehicle according to an embodiment of the present invention. Referring to FIG. 1, a vehicle 10 is an electric vehicle equipped with a battery 12 and a power generation device 18 as a driving power source. For example, the vehicle 10 is a plug-in hybrid vehicle configured to be able to charge the battery 12 from the outside. . The vehicle 10 can be connected to the external charger 200 by a power cable. The external charger 200 can charge the battery of the vehicle 10.

  The battery evaluation device 100 is a device for evaluating the life of a battery mounted on a vehicle and notifying the user of the remaining value of the battery. The external charger 200 and the battery evaluation device 100 are disposed, for example, in the user's garage, and the user can connect them to the vehicle as necessary to determine the battery life.

  The battery 12 has a lifetime because it deteriorates with use. This is because the internal resistance of the battery increases and the charge / discharge capacity (battery capacity) gradually decreases as the vehicle travels for a long time. Therefore, it is desirable for the user to periodically grasp the remaining life of the battery.

  As a factor that greatly affects the life of the battery, there is a variation in charge / discharge capability between battery modules that are aggregates of cells constituting the battery. The degree of deterioration of each battery module is not uniform due to variations in quality during manufacture, variations in temperature conditions within the battery, and the like. Even when the battery is a new battery, even if the variation in the charge / discharge capacity between the battery modules is small, the deterioration is accumulated as the battery is used, and the dispersion in the charge / discharge capacity between the battery modules increases. These battery modules are connected in series within the battery pack. Therefore, when the charge / discharge capacity (battery capacity) of one battery module is lowered, the charge / discharge capacity (battery capacity) of the entire battery is affected.

  Electricity that can be used when the charge / discharge capacity (battery capacity) decreases due to aging of the battery, even if the current value (for example, SOC 80%) at the time of full charge can be used from the management lower limit value (for example, SOC 20%). The amount of energy changes.

  When refresh processing is performed to reduce variation in charge / discharge capacity between battery modules, the battery capacity of the entire battery may increase. The battery evaluation apparatus 100 performs a refresh process before evaluating the battery life, calibrates the variation between the battery modules, and then evaluates the life.

  The user first connects the external charger 200 and the battery evaluation device 100 to the vehicle 10. Then, the battery evaluation apparatus 100 is caused to start a refresh process. Thereafter, discharging is performed from the battery having the specified remaining capacity by the external charger 200 to the remaining capacity of the management lower limit value by the battery evaluation apparatus 100, and the discharged electric energy is measured.

  However, even if this amount of electric power is notified to the user as it is, the user does not know how much influence the deterioration of the battery has on the vehicle. Therefore, the battery evaluation device 100 calculates a travelable distance when traveling on a travel course designated by the user based on the measured electric energy, and notifies the user of information regarding the calculated travelable distance. In the case of a hybrid vehicle, this travelable distance is the EV travelable distance. The hybrid vehicle can perform HV traveling using an engine and EV traveling using only a motor. The EV travelable distance is a distance at which the EV travel that travels using only the motor without using the engine can be continued when the battery 12 is charged to a predetermined amount.

  Below, the structure of the battery evaluation apparatus 100 and the process which evaluates the lifetime of a battery are demonstrated in detail.

  FIG. 2 is a diagram for explaining the configuration and connection relationship of the battery evaluation apparatus 100. Referring to FIG. 2, battery evaluation device 100 includes a refresh control unit 102, an evaluation control unit 104, and an information terminal 106.

  The refresh control unit 102 is connected to the battery 12. The battery 12 includes battery modules MA to MD. The refresh control unit 102 includes a matrix of relays that can freely change the connection relationship between the battery modules MA to MD. During normal use (such as during travel), the battery modules MA to MD are connected in series between the positive power line PL and the negative power line NL via the system main relays SMRB and SMRG of the vehicle 10, and are connected to the power generation device 18. Supply power.

  The power generation device 18 generates the driving force for driving the vehicle 10 using the electric power stored in the battery 12. Although not particularly illustrated, the power generation device 18 includes, for example, an inverter that receives power from the battery 12, a motor driven by the inverter, a drive wheel driven by the motor, and the like. When vehicle 10 is a hybrid vehicle, power generation device 18 further includes a generator for charging battery 12 and an engine capable of driving the generator.

  When the refresh control unit 102 is connected to the battery 12, the series connection of the battery modules MA to MD is released, and the battery module selected from the battery modules MA to MD based on the command of the evaluation control unit 104 is the positive power line. Connected between PL and negative power line NL.

  The battery ECU 14 of the vehicle measures each voltage of the battery modules MA to MD. The evaluation control unit 104 acquires the voltage of each battery module from the battery ECU 14, and selects the battery module whose voltage is higher than the specified value as the battery module to be discharged. Then, the evaluation control unit 104 controls the discharging electric load 16 to discharge the selected battery module until it reaches a predetermined state.

  As the electrical load 16 for discharge, for example, an electrical device such as an on-vehicle air conditioner, wiper, or headlamp can be used. The voltage supplied from the battery 12 via the refresh control unit 102 is converted into a voltage by a DC-DC converter (not shown) or the like as necessary and supplied to the on-vehicle electrical equipment.

  The information terminal 106 registers and acquires necessary information by communicating with an input unit 112 for a user to input various settings, a display unit 110 for presenting various types of information to the user, and an external manufacturer database 300. And a communication unit 114. The user can use a personal digital assistant (PDA), a smart phone, etc. as the information terminal 106, for example.

  The manufacturer database 300 stores battery type information of the vehicle used by the user, battery evaluation information from the time of the new vehicle sent to the latest transmitted from the user, and the like. When the user operates the information terminal 106 to evaluate the battery, the user can also display the information accumulated in the manufacturer database 300 on the display unit 110 to check the change in the battery state over time. it can.

  FIG. 3 is a main flowchart of a process for evaluating the life of the battery. The process of this flowchart is executed in a state where the vehicle has finished traveling and is parked in the user's garage.

  When the battery evaluation process is started, first, in step ST1, the evaluation control unit 104 of the battery evaluation apparatus 100 causes the refresh control unit 102 to execute a refresh process for uniformly discharging the battery modules MA to MD. Details of the refresh process in step ST1 will be described with reference to the flowchart of FIG.

  FIG. 4 is a flowchart for explaining the details of the refresh process. The process of this flowchart is a process executed when the process of ST1 in FIG. 3 is executed.

  First, in step ST100, the user performs an operation of stopping the traveling system of the vehicle 10. Accordingly, system main relays SMRB and SMRG are cut off in response to vehicle 10, and power generation device 18 and electric load 16 for discharge are disconnected from battery 12 (READY OFF).

  Subsequently, in step ST101, the charging cable of the external charger 200 is connected to the inlet of the vehicle by the user, and the battery 12 is fully charged by the external charger 200. Subsequently, in step ST102, the battery evaluation device 100 is connected to the battery 12 and the battery ECU 14 by the user. In step ST103, the user inputs refresh conditions from the input unit 112 of the information terminal 106. The refresh condition is a condition including an end voltage for completing the discharge of the voltage of each battery module, and designation of an electric load used for discharging from the battery 12 at the time of refresh. Here, an in-vehicle electrical component is used as an electrical load to be discharged. For this reason, in step ST104, the user performs an operation of starting the traveling system of the vehicle 10 in order to be able to use the in-vehicle electrical component. Accordingly, in system 10, system main relays SMRB and SMRG are turned on, and battery 12 is connected to discharging electrical load 16 (READY ON).

  Subsequently, in step ST105, a load to be used for the refresh process is selected based on the refresh condition. The user can specify, for example, an air conditioner, a wiper, a headlamp, or other in-vehicle electrical components as a load. It should be noted that the electrical load and the state thereof are not necessarily the same as the previous time, and may be changed each time according to the user's needs, such as cooling the air conditioner on a hot day and heating the air conditioner on a cold day.

  Subsequently, in step ST106, discharge from the battery 12 is started. When the discharge is started, the battery ECU 14 monitors the voltages of the battery modules MA to MD. In many cases, the refresh process may interrupt the discharge of the load. Therefore, in order to measure the open voltage (OCV) of the battery module, the current may be temporarily interrupted.

  In step ST107, the evaluation control unit 104 acquires the voltages of the battery modules MA to MD from the battery ECU 14, and in step ST108, changes the internal connection of the refresh control unit 102 so as to disconnect the battery module that has reached the specified voltage from the discharge circuit. To do.

  If all the battery modules are not completely discharged in step ST109, the process returns to step ST107 and the discharge process is continued. On the other hand, if all the battery modules have been discharged in step ST109, the process proceeds to step ST110 to complete the refresh.

  Returning to FIG. 3 again, when the refresh process in step ST1 ends, the charge process is executed in step ST2. In the charging process, the battery 12 is charged using the external charger 200 until the charging state (SOC) when the user departs normally is reached.

  In this case, since the charging is performed immediately after the completion of the refresh process, the charging amounts of the battery modules MA to MD have little variation. For this reason, even if charging is performed up to the same SOC, if the variation is large in the state before the refresh, the amount of energy (kWh) charged after the refresh process is increased.

  Subsequently, in step ST3, a load to be used for battery evaluation is selected. When evaluating the battery, it is desirable to execute the discharge from the battery 12 in the same state as possible in the past. The user can specify, for example, an air conditioner, a wiper, a headlamp, and other in-vehicle electrical components as a load during battery evaluation. The evaluation control unit 104 can store the electrical load used at the previous evaluation together with the evaluation data in the manufacturer database 300 or other storage device. Preferably, in order to increase the accuracy of battery evaluation, the same electrical load as in the previous state is used in the same state with reference to the data stored at the time of the current evaluation. However, the electrical load and the state thereof are not necessarily the same as the previous time, and may be changed according to the needs of the user, such as cooling the air conditioner on a hot day and heating the air conditioner on a cold day.

  In step ST4, the battery 12 is discharged by the selected electric load. Then, in step ST5, it is determined whether or not the discharge is completed up to a specified value (for example, in the case of a hybrid vehicle, the SOC management lower limit value for ending EV traveling).

  In step ST5, when the discharge to the specified value is not completed, the process proceeds to step ST6. In step ST6, a diagnosis process is performed to check whether there is an abnormality in the module voltage or temperature of the battery 12, and in step ST7, it is determined whether the diagnosis result of the battery 12 is normal.

  If the diagnosis result of the battery 12 is not normal in step ST7 (NO in ST7), the user is notified that the battery is abnormal in step ST8, and the battery evaluation ends. If the diagnosis result of the battery 12 is normal in step ST7, the process returns to step ST5 and the discharge is continued.

  If the discharge to the specified value has been completed in step ST5, the process proceeds to step ST9. In step ST9, a power consumption integrated value S1 (kWh) that is a value obtained by integrating the power consumed in the discharge from the start of discharge in step ST4 to the specified value is calculated. As a result, the amount of electrical energy that can be used by the vehicle 10 for EV travel in the current state of battery deterioration has been determined.

  The processing so far is meaningful in that the change width ΔSOC (%) of the SOC (%) indicated by the ratio is converted into the electric energy amount as an absolute amount with respect to the battery capacity which decreases with the aging of the battery. There is. In other words, even if ΔSOC (for example, 60%) can be used for EV travel from the current value (for example, SOC 80%) at the time of full charge to the control lower limit value (for example, SOC 20%), the battery capacity can be As the amount of electric energy that can be used decreases, the amount of usable electric energy changes, so that the amount of usable electric energy can be known by battery evaluation.

  However, even if the amount of electric energy (power consumption integrated value S1) that can be used for EV driving is found by battery evaluation, if the amount is shown to the user as it is, the user can see what effect appears in the vehicle. Hateful.

  Therefore, in the present embodiment, the evaluation result of the battery is displayed to the user by the EV travelable distance. However, the EV travelable distance is affected by the topography of the course on which the user travels, the acceleration / deceleration situation, the traffic jam situation due to the running time zone, and the like. If the EV travel distance that is far from the actual travel of the user is presented, the user will not trust the evaluation.

  Therefore, in order to present the EV travelable distance in the course on which the user actually travels, a reference travel course for battery evaluation is set based on the user's input in step ST10.

  FIG. 5 is a diagram for explaining a reference running course for battery evaluation. In FIG. 5, a commuting route that is one of the reference traveling courses registered in advance by the user is shown on the navigation screen. For example, a course can be registered or a reference course can be selected from a plurality of registered courses by operating a navigation screen or an input unit of an information terminal.

  Returning to FIG. 3 again, when the setting of the reference travel course in step ST10 is completed, in step ST11, the EV travel reference distance SK0 and the power consumption reference amount S0 of the reference travel course are read from the manufacturer database and other storage units. The power consumption reference amount S0 is data acquired by traveling in advance on the reference traveling course when the battery 12 is relatively new. In step ST12, the latest EV travel distance SK1 is calculated.

Simply, the latest EV travel distance SK1 is obtained by multiplying the EV travel reference distance SK0 by the ratio of the power consumption integrated value S1 and the power consumption reference amount S0. (SK1 = SK0 × S1 / S0)
In addition, considering the topography and the like, the reference travel course data is registered for each finer distance, and if the travel distance when the integrated value reaches S1 is obtained, the EV travel distance SK1 can be further accurately obtained. Can do.

  Next, in step ST13, if the EV travel distance SK1 is not equal to or greater than the life reaching specified value (NO in ST13), the user is warned in step ST15 that the battery 12 has reached the life.

  On the other hand, in step ST13, if EV travel distance SK1 is equal to or greater than the life reaching specified value, in step ST14, a battery evaluation result comparing SK1 and SK0 is output and notified to the user.

  FIG. 6 is an example showing the battery evaluation results in terms of power consumption. FIG. 7 is a first example showing the evaluation result of the battery in terms of EV travel distance. FIG. 8 is a second example showing the evaluation result of the battery in terms of the EV travel distance.

  Referring to FIG. 6, at evaluation time t0, a dischargeable power consumption reference amount S0 when evaluated at the time of a new vehicle is displayed. Further, FIG. 6 shows a state in which the amount of power that can be discharged from the battery 12 gradually decreases as the evaluation time becomes later, for example, as the evaluation is performed every year. The reason why the power consumption is slightly recovered at the evaluation time t1 is that the entire battery capacity is recovered by executing the refresh process after the variation in the battery capacity of the battery module is enlarged.

  In addition, as the secular change progresses and the number of evaluations is repeated, the power consumption that can be discharged is reduced to the power consumption SL corresponding to the battery life at the evaluation time t2, and the battery 12 reaches the life.

  Referring to FIG. 7, the evaluation result displayed when “commuting course” is set as the reference traveling course in step ST10 of FIG. 3 is shown. In this case, the EV travel reference distance SK0 when the driver A who uses the vehicle 10 for commuting actually travels the vehicle is registered as an initial value. At the evaluation time t0, the EV travel reference distance SK0 that is an initial value is displayed. FIG. 7 shows an EV travel distance SK1 that is a value obtained by converting the power consumption integrated value S1 in FIG. 6 at the evaluation time point t1. As described above, the change in the EV travel distance can more easily show the user the degree of deterioration of the battery 12 (the degree of approaching the life). In this case, by displaying a broken line indicating the distance SKL which is a value obtained by converting SL in FIG. 6, the user can grasp how long the service life will be reached.

  FIG. 8 is an example in which the EV travel distance when traveling on a travel course “shopping course” different from FIG. 7 is shown. For example, a different traveling course “shopping course” is a traveling course when going out for shopping in the daytime. In this case, the driver is also changed from driver A to driver B. The EV travel reference distance SK0A when the driver B who uses the vehicle 10 for shopping actually travels the vehicle is registered as an initial value.

  At the evaluation time point t0, an EV travel reference distance SK0A that is an initial value is displayed. FIG. 8 shows the EV travel distance SK1A, which is a value obtained by converting the power consumption integrated value S1 in FIG. 6 at the evaluation time point t1. As another example of the traveling course, “commuting course” or the like may be selectable.

  You may display the transition of a fuel consumption as output content of an evaluation result. FIG. 9 is an example of a screen showing changes in fuel consumption.

  In FIG. 9, the battery is evaluated every year, and converted to the fuel consumption when traveling on the registered standard course, it is shown how much the fuel consumption has decreased with respect to the fuel consumption at the time of delivery of the new vehicle. Yes. For example, in the case of a plug-in hybrid vehicle, the rate at which the EV travel distance decreases with respect to the registered reference course on the assumption that the vehicle is fully charged at the travel start point is used as a method for converting to fuel consumption. What is necessary is just to make it reflect in a fuel consumption fall.

  In addition, although said process demonstrated the example performed in the state where the vehicle is parked in a user's garage, it is not limited to this. For example, in a vehicle such as a business vehicle, when the user mounts the battery evaluation device 100 on the vehicle and carries it with him / her and wants evaluation during parking, the battery evaluation device 100 is connected to the battery, and the battery life is similarly evaluated. can do. In the case of a hybrid vehicle, charging at the time of evaluation may be performed by an engine and a generator instead of using an external charger.

[Modification]
Although the battery evaluation apparatus 100 has been described as being disposed in a user's garage, the battery evaluation apparatus 100 may be a facility that is permanently installed in a dealer or a facility that is permanently installed in another location.

  FIG. 10 is a diagram showing a configuration of a modified example. The configuration shown in FIG. 10 includes a refresh control unit 102A instead of the refresh control unit 102, and further includes a DC / DC converter 402 and a dealer maintenance power supply 404. Is the same as FIG.

  The battery 12 is connected to the DC / DC converter 402 via the refresh control unit 102A. The refresh control unit 102 </ b> A is configured to be able to connect any selected battery module among the battery modules MA to MD to the DC / DC converter 402. The DC / DC converter 402 performs voltage conversion between the selected battery module and the dealer maintenance power supply 404.

  The user can have the battery 12 evaluated together whenever the dealer receives an inspection. The user can receive only the evaluation of the battery at the dealer. In the case of the battery evaluation apparatus 100 installed at the dealer, the battery maintenance and power supply 404 that can freely adjust charging / discharging of the battery 12 performs refresh processing and discharging of the battery 12 to perform more detailed battery abnormality diagnosis. You may comprise as follows.

  If the battery evaluation apparatus 100 is arranged at a dealer or the like, when the battery evaluation is performed, the battery can be quickly replaced when the battery is abnormal or the life of the battery has been reached.

  In this embodiment, an example of evaluating a battery of a hybrid vehicle has been described. However, the vehicle may not be a hybrid vehicle, and a fuel cell vehicle or any other vehicle equipped with a battery that can be charged from the outside of the vehicle. A battery evaluation device may be applied to an electric vehicle. Moreover, although the refresh process is a process for eliminating the variation between the battery modules, the refresh process may be for eliminating the variation between the battery cells.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  DESCRIPTION OF SYMBOLS 10 Vehicle, 12 Battery, 14 Battery ECU, 16 Electric load for discharge, 18 Power generation apparatus, 100 Battery evaluation apparatus, 102, 102A Refresh control part, 104 Evaluation control part, 106 Information terminal, 110 Display part, 112 Input part, 114 communication unit, 200 external charger, 300 manufacturer database, 402 DC / DC converter, 404 power supply for dealer maintenance, MA to MD battery module, NL negative power line, PL positive power line.

Claims (3)

An evaluation apparatus for evaluating a battery including a plurality of battery modules mounted on a vehicle,
A refresh control unit configured to change connection of the plurality of battery modules and discharge each battery module;
An evaluation control unit that instructs the refresh control unit to discharge a battery module whose voltage is higher than a specified value;
After performing the battery refresh process , the evaluation control unit performs discharging from the battery having a specified remaining capacity to the remaining capacity of the control lower limit value using an in-vehicle electrical device as an electrical load for discharge. A battery evaluation apparatus that notifies the user of information relating to a travelable distance when traveling on a travel course designated by the user based on the discharged electric energy. The electrical device is a specified device among a plurality of devices,
The evaluation control unit stores device information for identifying the electrical equipment in a storage device when discharging is performed, reads the device information from the storage device at the next battery evaluation, and uses the same device as the previous time. The battery evaluation apparatus according to claim 1, wherein the battery is discharged. The evaluation control unit causes a storage device to store fuel consumption when traveling a registered travel course every time a battery is evaluated, and presents the user with a history of changes in the fuel consumption to date. The battery evaluation apparatus according to 1.

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