Patent Application
20130317690
1. Field of the Invention
The present invention relates to a vehicle battery diagnosis apparatus.
2. Background Information
Among diagnosis apparatuses that diagnose a secondary battery mounted in an electric vehicle, there is known an apparatus that presents a plurality of control plans for extending the life of a battery on the basis of diagnostic information, which includes usage conditions of the battery, and that updates vehicle control information so that the vehicle control information corresponds to a control plan selected by a user (Japanese Unexamined Patent Application Publication No. 2010-119223).
However, the above-described diagnosis apparatus according to the related art has a problem that, though the life of the battery is extended, a control plan which imposes restrictions on a user is presented, and thus the existence value of a vehicle is decreased.
An object of the present invention is to suppress both degradation of a battery and a decrease in the existence value of a vehicle.
In the present invention, in the case of diagnosing a history of a usage state of a battery and presenting a suppression measure against battery degradation, presentation of an alternative suppression measure is prohibited if the alternative suppression measure for a factor responsible for degradation does not satisfy a presentation criterion, and thereby the above-described object is achieved.
According to the present invention, even if there is an alternative suppression measure for a factor responsible for degradation, the alternative suppression measure is not presented if it does not satisfy a presentation criterion. Thus, degradation of a battery can be suppressed without decreasing the existence value of a vehicle.
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
A secondary battery V1 is a lithium-ion secondary battery or a nickel-hydride secondary battery that supplies power mainly to a vehicle-driving motor generator V3. The secondary battery V1 may supply power to a vehicle-mounted device other than the vehicle-driving motor generator V3, for example, a heater of an air conditioner, a compressor-driving motor, and an electrical device. Direct-current power of the secondary battery V1 is converted to alternating-current power by an inverter V2, and is supplied to the vehicle-driving motor generator V3, which is a three-phase alternating-current motor. When the vehicle-driving motor generator V3 shifts to a regeneration mode, alternating-current power generated by the vehicle-driving motor generator V3 is converted to direct-current power by the inverter V2, and is stored in the secondary battery V1.
A state of charge (SOC) of the secondary battery V1 is detected by a battery controller V4 and is output to a vehicle controller V5. The vehicle controller V5 calculates an output torque required for the vehicle-driving motor generator V3 on the basis of the amount of pressing down of an accelerator pedal by a driver, and outputs the calculation result to the battery controller V4. The battery controller V4 controls the inverter V2, and thereby supplies power corresponding to the required torque to the vehicle-driving motor generator V3.
The secondary battery V1 can be charged by being connecting to a charger 3, which is provided in a charging stand or a house of a user. As charging modes, a normal charging mode in which charging is performed at a voltage of about 100 to 200 V over a relatively long time, and a quick charging mode in which charging is performed by applying a high voltage of about 200 V over a relatively short time are set. The normal charging mode or the quick charging mode is selected in accordance with the specifications of a charging inlet on the vehicle side and the charger 3 of the charging stand or the like. The battery controller V4 counts the number of times charging in the normal charging mode has been performed on the vehicle, the number of times charging in the quick charging mode has been performed on the vehicle, and the total number of times charging in the normal charging mode or the quick charging mode has been performed on the vehicle, and records the count result.
At the time of charging the secondary battery V1, the user can select either of a standard-life mode in which charging continues till the SOC becomes 100%, and a long-life mode in which the SOC is limited to 80% or less. In accordance with the setting performed by the user, the battery controller V3 controls the SOC at the time of charging. That is, in a case where charging is performed in the long-life mode, charging is stopped when the SOC of the secondary battery V1 reaches 80%, and further charging is prohibited.
Temperature data supplied from an outside-air-temperature sensor V6 for detecting an outside air temperature and a battery-temperature sensor V7 for detecting a temperature of the secondary battery V1 is input, as a factor related to degradation of the secondary battery V1 (correlated to a decrease in battery capacity), to the vehicle controller V5. The outside-air-temperature sensor V6 is provided outside the vehicle, and the battery-temperature sensor V7 is provided in a module pack or the like of the secondary battery V1.
At the time of driving the vehicle, the user can select either of standard-mode driving in which the output of the vehicle-driving motor generator V3 is not limited, and an eco-mode driving in which the output of the vehicle-driving motor generator V3 is limited and economical efficiency is high. In accordance with the setting performed by the user, the vehicle controller V5 controls the output of the vehicle-driving motor generator V3. That is, in a case where the vehicle is driven using eco-mode driving, the power output to the vehicle-driving motor generator V3 is limited to a certain value even if the amount of pressing down of the accelerator pedal is large, and power supply over the certain value is prohibited. Note that, when eco-mode driving is selected, the power output to electrically-powered devices other than the vehicle-driving motor generator V3 (heater, compressor motor, electrical device, etc.) may also be limited. The vehicle controller V5 records an average value of power output to the vehicle-driving motor generator V3 in each term of driving: from when an ignition key is turned on to when the ignition key is turned off
The battery controller V4 records the date of manufacture of the secondary battery V1, the time period from the date of manufacture to the present, and the time period over which the secondary battery V1 was left in a certain SOC or more (for example, SOC=90%). Also, the battery controller V4 records the SOC at the time when a charging operation by the charger 3 started, and the number of times charging has been performed.
Next, the diagnosis apparatus 1 will be described. The diagnosis apparatus 1 according to this example includes a degradation degree calculation unit 11, an alternative suppression measure extraction unit 12, a storage unit 13, and a diagnosis unit 14. These units can be constituted by a microcomputer including a CPU, a ROM, a RAM, and so forth.
The degradation degree calculation unit 11 receives history data about a usage state related to a factor responsible for degradation of the secondary battery V1, and calculates the degrees of battery degradation by using the history data about the usage state. Specifically, the degradation degree calculation unit 11 calculates quick charging frequency A, charge level frequency at the start of charging B, power consumption frequency C, and left-at-high-charge-level duration rate D, and also calculates a battery temperature at the start of charging, the relationship between an outside air temperature and a battery temperature, and a battery temperature at the start of driving.
Quick charging frequency A is one of the degrees of battery degradation which is defined by (Nq/N)×100, where Nq represents the number of times quick charging has been performed, and N represents the total number of times charging has been performed, and is a characteristic value in which the degree of battery degradation increases as quick charging frequency A increases. The number of times quick charging has been performed Nq and the total number of times charging has been performed N are read out from a memory of the battery controller V4 via the vehicle controller V5.
Charge level frequency at the start of charging B is one of the degrees of battery degradation which is defined by ∫(Fn×αn)dSOC, where Fn represents a charging frequency of each SOC at the start of charging, and αn represents a weight coefficient of each SOC, and is a characteristic value in which the degree of battery degradation increases as charge level frequency at the start of charging B increases.
For example, SOC is divided into sections in units of 20%, that is, 0 to 20%, 20 to 40%, 40 to 60%, 60 to 80%, and 80 to 100%, and the frequencies of the SOC level at the start of charging in the individual sections are counted. Also, because the degree of battery degradation increases if charging is performed when SOC is in a high level, a weight coefficient when SOC is in a high level is set to be large, and a weight coefficient when SOC is in a middle to low level is set to be small. Then, the total sum of the values which are obtained by multiplying charging start frequencies in the individual sections by respective coefficients is calculated, and thereby charge level frequency at the start of charging B is calculated. The charging frequency of each SOC at the start of charging Fn and the weight coefficient an are read out from the memory of the battery controller V4 via the vehicle controller V5.
Power consumption frequency C is one of the degrees of battery degradation which is defined by W×β, where W represents average output power of the secondary battery V1 during certain driving, such as one trip from when an ignition key is turned on to when the ignition key is turned off, and β represents a weight coefficient, and is a characteristic value in which the degree of battery degradation increases as power consumption frequency C increases. The weight coefficient β increases as the average output power W increases. The average output power W of the secondary battery V1 during one trip and the weight coefficient β are read out from the memory of the battery controller V4 via the vehicle controller V5.
Left-at-high-charge-level duration rate D is one of the degrees of battery degradation which is defined by t/t0, where t represents the time period over which the secondary battery V1 is left unused in a state of a certain SOC (for example, 90%) or more, and t0 represents the elapsed time from the date of manufacture of the battery to the present, and is a characteristic value in which the degree of battery degradation increases as left-at-high-charge-level duration rate D increases. The time period t over which the secondary battery V1 is left unused in a state of the certain SOC or more and the elapsed time t0 from the date of manufacture of the battery to the present are read out from the memory of the battery controller V4 via the vehicle controller V5.
The alternative suppression measure extraction unit 12 extracts an alternative suppression measure which is stored in the storage unit 13, for a factor which exceeds a certain allowable value among the degrees of degradation calculated by the degradation degree calculation unit 11. The storage unit 13 stores alternative suppression measures for factors responsible for battery degradation.
Now, factors responsible for degradation of the secondary battery V1 will be described.
The factor “battery temperature is high X1” includes “battery temperature during charging is high X11” and “battery temperature during driving is high X12”. The factor “battery temperature during charging is high X11” includes “battery temperature at the start of charging is high X111”, “quick charging frequency is high X112”, and “outside air temperature is high X113”. The factor “battery temperature during driving is high X12” includes “outside air temperature is high X113”, “battery temperature at the start of driving is high X121”, and “output limitation frequency of the secondary battery V1 is high X122”.
The factor “battery temperature at the start of charging is high X111” is strongly correlated to the factor related to use “performing charging immediately after driving, particularly after high-load driving Y1”. Also, the factor “quick charging frequency is high X112” is strongly correlated to the factor related to use “frequently performing quick charging Y2”, the factor “outside air temperature is high X113” is strongly correlated to the factor related to use “parking outdoors Y3”, the factor “battery temperature at the start of driving is high X121” is strongly correlated to the factor related to use “driving immediately after charging, particularly after quick charging Y4”, and the factor “output limitation frequency is high X122” is strongly correlated to the factor related to use “average vehicle speed is high, average output power to the vehicle-driving motor generator V3 is high, and power consumption of the air conditioner and heater is high Y5”.
The factor “charge level is high X2” includes “charge level at the start of charging is high X21” and “charge level when the secondary battery V1 is not being used is high X22”. The factor “charge level at start of charging is high X21” is strongly correlated to the factor related to use “repeating short-distance driving (hereinafter referred to as short driving) and immediate charging Y6”, and the factor “charge level when the secondary battery V1 is not being used is high X22” is strongly correlated to the factor related to use “leaving the vehicle in high charge level state after driving or charging Y7”.
The factor “the number of times charging has been performed is large X3” includes “the number of times normal charging or quick charging has been performed is large X31”. The factor “the number of times normal charging or quick charging has been performed is large X31” is strongly correlated to the factor related to use “the number of times normal or quick charging has been performed is large, and repeating short driving and immediate charging Y8”.
The factors related to use by a user Y1 to Y8 illustrated in
That is, a suppression measure “avoiding charging immediately after driving” for the factor related to use “performing charging immediately after driving, particularly after high-load driving Y1”; a suppression measure “recommending normal charging instead of quick charging” for the factor related to use “frequently performing quick charging Y2”; a suppression measure “avoiding parking outdoors” for the factor related to use “parking outdoors Y3”; a suppression measure “avoiding driving immediately after charging” for the factor related to use “driving immediately after charging, particularly after quick charging Y4”; a suppression measure “recommending eco-mode driving for limiting power consumption” for the factor related to use “average vehicle speed is high, average output power to the vehicle-driving motor generator V3 is high, and power consumption of the air conditioner and heater is high Y5”; a suppression measure “recommending a long-life mode for limiting a full-charge level” for the factor related to use “repeating short driving and immediate charging Y6”; a suppression measure “recommending a long-life mode for limiting a full-charge level” for the factor related to use “leaving the vehicle in high charge level state after driving or charging Y7”; and a suppression measure “recommending a long-life mode for limiting a full-charge level” for the factor related to use “the number of times normal or quick charging has been performed is large, and repeating short driving and immediate charging Y8”, are stored in the storage unit 13.
The alternative suppression measure extraction unit 12 illustrated in
The diagnosis unit 14 permits output of an alternative suppression measure extracted by the alternative suppression measure extraction unit 12 to the output unit 2 as a suppression measure if the alternative suppression measure satisfies a certain presentation criterion, and prohibits presentation of the alternative suppression measure as a suppression measure if the alternative suppression measure does not satisfy the presentation criterion. The diagnosis unit 14 sets, as the presentation criterion, whether or not a function of the vehicle is impaired. If the alternative suppression measure extracted by the alternative suppression measure extraction unit 12 impairs a function of the vehicle, the diagnosis unit 14 prohibits presentation of the alternative suppression measure. If the alternative suppression measure impairs a performance of the vehicle but does not impair a function of the vehicle, the diagnosis unit 14 permits presentation of the alternative suppression measure. In other words, the diagnosis unit 14 prohibits presentation of an alternative suppression measure which prohibits use or parking of the vehicle, an alternative suppression measure which prohibits charging of the secondary battery, and an alternative suppression measure related to a natural environment, because these alternative suppression measures impair a function of the vehicle.
That is, the diagnosis unit 14 prohibits presentation of the suppression measure “avoiding charging immediately after driving” for the factor related to use “performing charging immediately after driving, particularly after high-load driving Y1”, among the above-described suppression measures, because this is an alternative suppression measure which prohibits charging of the battery. Also, the diagnosis unit 14 prohibits presentation of the suppression measure “avoiding parking outdoors” for the factor related to use “parking outdoors Y3”, because this is an alternative suppression measure related to a natural environment, and prohibits presentation of the suppression measure “avoiding driving immediately after charging” for the factor related to use “driving immediately after charging, particularly after quick charging Y4”, because this is an alternative suppression measure which prohibits use of the vehicle. In addition, the diagnosis unit 14 prohibits presentation of the suppression measure “avoiding leaving the vehicle in a high charge level” for the factor related to use “leaving the vehicle in high charge level state after driving or charging Y7”, because this is an alternative suppression measure which prohibits parking of the vehicle.
The output unit 2 is constituted by a printer which outputs an alternative suppression measure output from the diagnosis unit 14 onto a paper medium, a display which displays an alternative suppression measure, or the like, and has a function of presenting an alternative suppression measure to the user.
The advice sheet illustrated in
Next, the operation of the diagnosis apparatus 1 according to this example will be described.
First, the diagnosis apparatus 1 and the vehicle controller V5 are connected to each other, and usage history data about the secondary battery V1, which is recorded in the vehicle controller V5 and the battery controller V3, is read into the degradation degree calculation unit 11 in step ST1.
In step ST2, the degradation degree calculation unit 11 calculates degradation degrees, such as quick charging frequency A, charge level frequency at the start of charging B, power consumption frequency C, left-at-high-charge-level duration rate D, the battery temperature at the start of charging, the relationship between an outside air temperature and a battery temperature, and the battery temperature at the start of driving, on the basis of the read usage history data about the secondary battery V1. In step ST3, the alternative suppression measure extraction unit 12 determines whether or not the individual calculation results of quick charging frequency A, charge level frequency at the start of charging B, power consumption frequency C, left-at-high-charge-level duration rate D, the battery temperature at the start of charging, the relationship between an outside air temperature and a battery temperature, and the battery temperature at the start of driving are lower than or equal to certain allowable values.
As a result of the determination performed in step ST3, the process proceeds to step ST8 for a degradation factor which is lower than or equal to the allowable value, and presents a message indicating that no suppression measures are necessary for the current usage history. Specifically, “The method which is currently being used does not have a factor responsible for a decrease in capacity.” is displayed in the advice item of the advice sheet in
As a result of the determination performed in step ST3, the process proceeds to step ST4 for a degradation factor which exceeds the allowable value, among quick charging frequency A, charge level frequency at the start of charging B, power consumption frequency C, left-at-high-charge-level duration rate D, the battery temperature at the start of charging, the relationship between an outside air temperature and a battery temperature, and the battery temperature at the start of driving, and an alternative suppression measure stored in the storage unit 13 is extracted.
In step ST5, it is determined whether or not the alternative suppression measure extracted in step ST4 satisfies the above-described presentation criterion. Specifically, if the alternative suppression measure extracted by the alternative suppression measure extraction unit 12 impairs a function of the vehicle, the process proceeds to step ST7, and presentation of the alternative suppression measure is prohibited. On the other hand, if the alternative suppression measure impairs a performance of the vehicle but does not impair a function of the vehicle, the process proceeds to step ST6, and presentation of the alternative suppression measure is permitted.
In the advice sheet illustrated in
Also, in the example illustrated in
As described above, according to the diagnosis apparatus 1 of this example, as a result of analyzing a factor responsible for degradation of the secondary battery V1 by the degradation degree calculation unit 11, the alternative suppression measure extraction unit 12 extracts an alternative suppression measure for battery degradation. If the diagnosis unit 14 determines that the alternative suppression measure impairs a function of the vehicle, in other words, if the alternative suppression measure is an alternative suppression measure which prohibits use or parking of the vehicle, an alternative suppression measure which prohibits charging of the secondary battery, or an alternative suppression measure related to a natural environment, the diagnosis unit 14 prohibits presentation of the alternative suppression measure because it impairs a function of the vehicle. As a result, degradation of the secondary battery V1 can be suppressed without imposing extreme restrictions on the user and without decreasing the existent value of the vehicle.
By using quick charging frequency A, charge level frequency at the start of charging B, power consumption frequency C, and left-at-high-charge-level duration rate D which have been calculated by the above-described degradation degree calculation unit 11, quick charging frequency A and the coefficient a thereof, charge level frequency at the start of charging B and the coefficient b thereof, power consumption frequency C and the coefficient c thereof, and left-at-high-charge-level duration rate D and the coefficient d thereof, in a case where a+b+c+d=1, a total degradation degree F which is defined by F=A×a+B×b+C×c+D×d may be output to the output unit 2.
Alternatively, the alternative suppression measures stored in the storage unit 13, the allowable values for the alternative suppression measure extraction unit 12, and the presentation criterion for the diagnosis unit 14 may be received from the outside of the diagnosis apparatus 1 and may be periodically updated. Furthermore, the diagnosis apparatus 1 is provided separately from the vehicle V in the example in
In the above-described embodiment, if the degradation degree calculated by the degradation degree calculation unit 11 exceeds a certain allowable value, the corresponding alternative suppression measure is extracted by the alternative suppression measure extraction unit 12, and, if the extracted alternative suppression measure does not satisfy the presentation criterion, the diagnosis unit 14 prohibits the presentation thereof. Alternatively, the diagnosis unit 14 may prohibit presentation of an alternative suppression measure if the alternative suppression measure does not satisfy the presentation criterion, and may permit presentation of an alternative suppression measure if the alternative suppression measure satisfies the presentation criterion, regardless of whether or not the degradation degree of the secondary battery V1 exceeds the certain allowable value, or independently of the determination. In this case, the degradation degree calculation unit 11 and the alternative suppression measure extraction unit 12 are not always necessary, and these units may be omitted. Alternatively, independently of a determination performed by the diagnosis unit 14, history data about a usage state of the secondary battery V1 may be read into the degradation degree calculation unit 11 from the vehicle controller V5, and a result about a degradation degree may be output to the output unit 2.
The above-described degradation degree calculation unit 11 corresponds to degradation degree calculation means and total degradation degree presentation means according to the present invention, the above-described alternative suppression measure extraction unit 12 corresponds to extraction means according to the present invention, the above-described storage unit 13 corresponds to storage means and update means according to the present invention, and the above-described diagnosis unit 14 corresponds to diagnosis means according to the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2010-251648 | Nov 2010 | JP | national |
This application is a U.S. National stage of International Application No. PCT/JP2011/073834, filed Oct. 17, 2011. This application claims priority to Japanese Patent Application No. 2010-251648, filed on Nov. 10, 2010. The entire disclosure of Japanese Patent Application No. 2010-251648 is hereby incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2011/073834 | 10/17/2011 | WO | 00 | 7/5/2013 |
