JP2003032804A - Temperature-up controlling device for secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently raise the temperature of a secondary battery that is mounted on a hybrid vehicle. SOLUTION: A controller 14 that controls the hybrid vehicle checks a dischargeable output of the battery when driving the vehicle. If it is smaller than a specified value A, the battery is discharged with the maximum dischargeable output. This discharge raise the temperature of the battery and the increase rate, which increases as the temperature rises, of the dischargeable output is checked. If the rate increases, discharging is continued judging the discharge is possible. If the rate becomes zero, an engine starts to charge the battery. This way, the discharging for raising the temperature of the battery is performed within the range that the dischargeable output increases so that it prevents overcharge from causing the drop of the dischargeable output and contributes to the improvement of fuel consumption performance of the vehicle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature control device for a secondary battery for driving mounted on a hybrid type vehicle.

[0002]

2. Description of the Related Art In a secondary battery involving a chemical reaction, the internal resistance increases as the battery temperature decreases, and the dischargeable output (discharge power) decreases. Therefore, when the hybrid type vehicle is used in a low temperature environment, the vehicle performance may deteriorate.

FIG. 6 is a diagram showing a fuel consumption rate of a vehicle for a dischargeable output of the secondary battery in a parallel hybrid type vehicle equipped with both the secondary battery and an engine. The horizontal axis shows the dischargeable output of the secondary battery, and the vertical axis shows the fuel consumption rate of the vehicle. In the figure, curve 1 shows the fuel consumption rate when traveling while discharging the secondary battery, and curve 2 shows the fuel consumption rate when traveling while charging the secondary battery. When traveling while charging the secondary battery, the generator is driven by the engine to charge the secondary battery, so compared to when traveling while discharging the secondary battery, the amount of energy required to charge the secondary battery is reduced. The consumption rate decreases.

The larger the dischargeable output of the secondary battery is, the longer the traveling distance using the motor as a drive source can be, so that the low efficiency operation state at the time of low engine speed when the vehicle is started can be sufficiently avoided. Will get better. When the dischargeable output of the secondary battery becomes zero, the fuel consumption rate of a vehicle equipped with only a normal engine is reached, and when the dischargeable output of the secondary battery can be produced as designed, the high performance of the original parallel hybrid type vehicle is achieved. You will be able to demonstrate fuel efficiency.

When the fuel efficiency performance of a vehicle is designed by the performance of the secondary battery at room temperature, the fuel efficiency performance at low temperature is deteriorated, and
If the fuel efficiency performance of the secondary battery at low temperature is designed, many secondary batteries will be installed, and the cost of the secondary battery will increase and the fuel efficiency of the vehicle will decrease due to the weight increase of the secondary battery. Therefore, normally, the fuel efficiency performance of the vehicle is designed while sacrificing the secondary battery performance at low temperatures. Therefore, running the vehicle at a low temperature of the secondary battery will result in a significant decrease in fuel efficiency compared to running at room temperature. However, if the temperature of the secondary battery can be raised quickly, the fuel efficiency can be improved. You can

As a method of raising the temperature of the secondary battery the fastest, it is conceivable to flow the maximum current value that the secondary battery can flow to the vehicle drive motor and the auxiliary equipment. For example, JP-A-11-
Japanese Laid-Open Patent Publication No. 26032 describes a technique for improving the vehicle performance at low temperatures by causing the maximum current value that can be passed by the secondary battery to flow through the vehicle drive motor and the auxiliary machine to raise the temperature of the secondary battery.

[0007] In the above technology, since the temperature rises due to discharge, in the case of an electric vehicle equipped with only a secondary battery, the temperature can be raised only to the extent that the charge amount SOC does not decrease. When applied to type vehicles, the discharge time can be set longer, so
The temperature of the secondary battery can be raised more effectively. In this case, for example, the maximum current value that can be supplied by the secondary battery is supplied to the vehicle drive motor and the auxiliary equipment to charge the secondary battery SOC SOC.
When the secondary battery is charged, the secondary battery is charged by the generator, and when the SOC of the secondary battery becomes more than a predetermined value, the charging is stopped, and the maximum current value that the secondary battery can flow is again set to the vehicle drive motor and auxiliary equipment. And the temperature of the secondary battery can be raised by repeating this.

FIG. 7 is a diagram showing the dischargeable output and the fuel consumption rate of the secondary battery when the temperature of the secondary battery is raised by repeating charging and discharging. The horizontal axis represents time, and the vertical axis represents the dischargeable output of the secondary battery and the fuel consumption rate of the vehicle. Here, switching between running while discharging the secondary battery and running while charging the secondary battery is performed when the dischargeable output of the secondary battery falls below a predetermined value. This predetermined value is set as the switching lower limit value (threshold value). In addition, switching between running while charging the secondary battery and running while discharging the secondary battery is performed when the charge amount of the secondary battery exceeds a predetermined value. The predetermined value of the charge amount is set as the switching upper limit value.

The time region is a region where the dischargeable output due to the low temperature is smaller than the switching lower limit value. In the time domain, since the dischargeable output of the secondary battery is equal to or lower than the switching lower limit value, the vehicle runs while charging the secondary battery, and when the SOC of the secondary battery exceeds the switching upper limit value, the secondary battery is discharged. The above-mentioned running is repeated in a short time period. The fuel consumption rate in the time region is poor because the time for charging the secondary battery is long and the dischargeable output of the secondary battery is low.

In the time domain, since the dischargeable output of the secondary battery is equal to or greater than the switching lower limit value, the secondary battery is running while discharging. Fuel consumption rate in the time domain is 2
Since the temperature rise due to the discharge of the secondary battery increases the dischargeable output of the secondary battery, the fuel consumption rate is better than in the time domain. When the dischargeable output of the secondary battery due to discharge becomes equal to or lower than the switching lower limit value, the time domain is entered.

In the time domain, traveling is performed while charging the secondary battery. Fuel consumption rate in the time domain is 2
Due to the increase in the dischargeable output of the secondary battery due to the increase in the SOC of the secondary battery, the fuel consumption rate has improved with the passage of time. When the state of charge SOC of the secondary battery becomes equal to or higher than the switching upper limit value, the time zone is entered. Hereinafter, running while discharging the secondary battery and running while charging the secondary battery are repeated to raise the temperature of the secondary battery. The dischargeable output rises as the temperature of the secondary battery rises.

[0012]

However, as shown in the above time region, the temperature of the secondary battery rises due to discharge, and accordingly, the dischargeable output also improves, while long-term discharge causes: This time, the amount of charge SOC decreases, and in the figure, the dischargeable output decreases on the contrary at a peak of 10 minutes. In this case, there is a problem in that the fuel consumption rate of the vehicle is decreased due to the relationship between the dischargeable output of the secondary battery and the fuel consumption rate shown in FIG.

Further, in order not to cause such a thing,
For example, if the running time is shortened while discharging the secondary battery and discharging is performed while maintaining the charge amount SOC, the effect of improving the dischargeable output due to the temperature rise of the secondary battery cannot be sufficiently obtained.
There arises a problem that the fuel consumption rate is not improved. The present invention has been made in view of the above-mentioned conventional problems, and it is an object of the present invention to provide a secondary battery temperature raising control device capable of raising the temperature of a secondary battery without lowering the dischargeable output. To aim.

[0014]

The invention according to claim 1 is
In a hybrid vehicle equipped with a secondary battery and a power source capable of charging the secondary battery, when the temperature of the secondary battery is low, the secondary battery is discharged to raise the temperature. A battery temperature raising control device, comprising: an increase rate calculation means for calculating an increase rate of a dischargeable output of a secondary battery with respect to a discharge time passage; and a mode switching means, wherein the mode switching means performs the calculation. The secondary battery is switched from discharging to charging according to the increase rate of the dischargeable output.

According to a second aspect of the present invention, there is provided temperature raising termination means, and the temperature raising termination means compares the dischargeable output at the time of completion of charging of the secondary battery with a predetermined value, and the dischargeable output is the above-mentioned. When the value is smaller than the predetermined value, the secondary battery is controlled to be repeatedly discharged and charged to raise the temperature.

According to a third aspect of the present invention, the increase rate calculating means calculates a charge amount of the secondary battery, and calculates a dischargeable output based on the calculated charge amount and the temperature of the secondary battery. However, the increase rate of the dischargeable output with respect to time is calculated.

According to a fourth aspect of the present invention, the mode switching means compares the calculated increase rate of the dischargeable output with a predetermined value, and when the increase rate of the dischargeable output is equal to or less than a predetermined value, The secondary battery was switched from discharging to charging.

According to a fifth aspect of the present invention, the predetermined value changes according to the amount of charge when the secondary battery is completely charged.

According to a sixth aspect of the present invention, the predetermined value is 2
It is assumed to change according to the temperature of the secondary battery. In the invention according to claim 7, the predetermined value changes according to the dischargeable output at the time of completion of charging of the secondary battery.

According to an eighth aspect of the invention, the power source is a power generating means driven by an engine.
In the invention according to claim 9, the power source is a fuel cell.

[0021]

According to the first aspect of the present invention, when the secondary battery is discharged, the rate of increase in the dischargeable output of the secondary battery with respect to the elapsed time of discharge is calculated, and the secondary battery is set in accordance with the calculated value. Since the discharge is switched to the charge, for example, the discharge can be switched to the charge when the increase rate is zero. In this case, it is possible to improve the dischargeable output as the temperature rises and prevent the dischargeable output from decreasing due to further discharge.

According to the second aspect of the present invention, the temperature raising termination means controls so as to repeat discharging and charging for raising the temperature of the secondary battery when the dischargeable output at full charge is smaller than a predetermined value. Therefore, the secondary battery can be heated up to the set dischargeable output.

The dischargeable output of the secondary battery can be obtained from the internal resistance of the secondary battery and the open circuit voltage. The internal resistance of the secondary battery is determined by the temperature of the secondary battery and the charge amount of the secondary battery, and the open circuit voltage of the secondary battery is determined by the charge amount of the secondary battery. Therefore, in the invention according to claim 3, the charge amount of the secondary battery is calculated, the dischargeable output is calculated based on the calculated charge amount and the temperature of the secondary battery, and the dischargeable output with respect to time is calculated. Since the rate of increase is calculated, a voltage sensor, a current sensor, and a temperature sensor that measures the temperature of the secondary battery can be provided, and the dischargeable output can be calculated using each measured value. This calculation can be calculated with high accuracy, especially for a lithium ion battery whose open circuit voltage largely depends on the charge amount.

In the invention according to the fourth aspect, the rate of increase in the dischargeable output is compared with a predetermined value, and when the dischargeable output becomes less than or equal to the predetermined value, the secondary battery is switched from discharging to charging. It is possible to set the switching timing according to the purpose only by setting the value.

According to the fifth aspect of the present invention, the predetermined value for determining the timing of switching from discharge to charge is changed according to the charge amount. Therefore, there is a correspondence relationship with the charge amount and the fuel consumption rate It is possible to improve.

According to the sixth aspect of the invention, the predetermined value for determining the timing of switching from discharging to charging is changed according to the temperature of the secondary battery, so that it has a corresponding relationship with the temperature of the secondary battery. It is possible to further improve the fuel consumption rate.

According to the seventh aspect of the invention, the predetermined value for determining the timing of switching from discharge to charge is changed according to the dischargeable output, so that the dischargeable output has a corresponding relationship with the fuel consumption. It is possible to improve the rate.

According to the eighth aspect of the invention, since the power generation means driven by the engine is used as the power source, the hybrid vehicle equipped with the engine can be used as the hybrid vehicle. As a result, the fuel efficiency performance of gasoline or the like for driving the engine is improved. Claim 9
In the described invention, since the fuel cell is used as the power source,
A hybrid vehicle equipped with a fuel cell power generation system can be used as the hybrid vehicle. As a result, the fuel consumption performance of hydrogen, oxygen, etc. that drives the fuel cell is improved.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described with reference to examples. FIG. 1 is a diagram showing a configuration of a hybrid vehicle to which the present invention is applied as a first embodiment.
In the figure, the solid line indicates the transmission path of mechanical force, and the dotted line indicates the power line. The broken line indicates the control line. The power train of the vehicle is composed of a generator motor 1, an engine 2, a clutch 3, a drive motor 4, a continuously variable transmission 5, a differential device 6 and two drive wheels 7. The output shaft of the generator motor 1, the output shaft of the engine 2, and the input shaft of the clutch 3 are connected to each other, and the output shaft of the clutch 3, the output shaft of the drive motor 4, and the input shaft of the continuously variable transmission 5 are mutually connected. It is connected.

When the clutch 3 is engaged, the engine 2 and the drive motor 4 serve as the vehicle propulsion source, and when the clutch 3 is disengaged, only the drive motor 4 serves as the vehicle propulsion source. The driving force of the engine 2 transmitted via the drive motor 4 and the clutch 3 is transmitted to the two drive wheels 7 via the continuously variable transmission 5 and the differential device 6.

The generator motor 1 and the drive motor 4 are AC motors such as a three-phase synchronous motor or a three-phase induction motor. The generator motor 1 is mainly used for starting the engine and generating electricity, and the drive motor 4 is mainly for propulsion and braking of the vehicle. Used for.

The clutch 3 is a powder clutch and can adjust the transmission torque. The continuously variable transmission 5 is a continuously variable transmission such as a belt type or toroidal type, and can continuously adjust the gear ratio. The generator motor 1 and the drive motor 4 are driven by inverters 8 and 9, respectively. The inverters 8 and 9 are connected to a secondary battery 11 via a common DC link 10, convert DC charging power of the secondary battery 11 into AC power, and supply the AC power to the generator motor 1 and the drive motor 4. The AC power generated by the generator motor 1 and the drive motor 4 is converted into DC power to charge the secondary battery 11.

Since the inverters 8 and 9 are connected to each other through the DC link 10, the electric power generated by the motor during the regenerative operation is directly supplied to the motor during the power running operation without passing through the secondary battery 11. Supply. Secondary battery 11
Is connected to the DC / DC converter 12 via the DC link 10 and supplies electric power to the auxiliary machine 13 of the vehicle.

The controller 14 controls the rotation speed of the engine 2, the output power and torque, the transmission torque of the clutch 3, the rotation speed and torque of the generator motor 1 and the drive motor 4, the gear ratio of the continuously variable transmission 5, and the secondary battery 11. Control the charging and discharging of the. The controller 14 has a secondary battery 1
Temperature sensor 15 for detecting temperature TB of 1 and secondary battery 1
Signals from the voltage sensor 16 that detects the terminal voltage VB of 1 and the current sensor 17 that detects the current value IB of the secondary battery 11 are input and have a function of calculating the charge amount SOC of the secondary battery 11.

Further, it has map data of the dischargeable output and the chargeable output of the secondary battery 11 with respect to the temperature TB of the secondary battery 11 and the charge amount SOC of the secondary battery 11, and the measured secondary battery temperature TB and calculation are carried out. The dischargeable output PB and the chargeable output of the secondary battery are calculated from the map data based on the charged amount SOC.

During operation, the controller 14 calculates the driving force distribution between the engine 2 and the drive motor 4 according to the operating state of the vehicle, and controls the vehicle so that the fuel consumption rate becomes maximum. In the initial stage of operation, the temperature of the secondary battery is judged based on the dischargeable output of the secondary battery, and if the temperature is low, the secondary battery is discharged to raise the temperature. In this embodiment, the secondary battery 11 is a lithium ion secondary battery.

Next, the control flow for raising the temperature of the secondary battery in the controller will be described with reference to the flowchart of FIG. This control starts when the ignition switch is turned on.

In step 100, the dischargeable output PB of the secondary battery is compared with a predetermined value A. The dischargeable output PB of the secondary battery is calculated by calculating the charge amount SOC of the secondary battery from the open circuit voltage value of the secondary battery detected by the voltage sensor 16, and the charge amount SOC and the temperature of the secondary battery detected by the temperature sensor 15. It is calculated from the map data with the value. The predetermined value A is the minimum dischargeable output that can maintain the fuel consumption performance as a design value, and is obtained by a vehicle experiment with the characteristics of the temperature and discharge output of the secondary battery.

When the dischargeable output PB is equal to or larger than the predetermined value A, the dischargeable output according to the set value is obtained from the secondary battery 11, so that the routine proceeds to step 108. After that, the vehicle is driven by the driving force of the secondary battery in the low-speed and high-load operating region according to the operating condition of the vehicle. In a region where the efficiency of the engine 2 is high, the engine is started to drive the vehicle. When the dischargeable output PB of the secondary battery is smaller than the predetermined value A in the comparison of step 100, it is determined that the temperature of the secondary battery is low, and therefore the fuel economy performance as the designed value cannot be obtained as a hybrid vehicle, Go to step 101.

In step 101, the power PV required for driving the vehicle is compared with the dischargeable output PB of the secondary battery. If the power PV required for driving the vehicle is larger than the dischargeable output PB of the secondary battery, Go to step 102. The power PV required to drive the vehicle is the dischargeable output PB of the secondary battery.
In the following cases, the process proceeds to step 103.

In step 102, the driving power PV required for driving the vehicle is distributed between driving by the driving motor at the dischargeable output PB of the secondary battery and driving by the remaining (PV-PB) engine, Car control. In step 103, the power PV required for driving the vehicle is driven by the secondary battery, the remaining (PB-PV) power is supplied to the auxiliary equipment, and the discharge power from the secondary battery is controlled to become PB. Steps 101, 102 and 103 form a mode in which the secondary battery runs while discharging. This traveling mode is called a discharge mode. In the discharge mode, the secondary battery discharges at the maximum dischargeable output.

When step 102 or 103 is completed, the routine proceeds to step 104, where the increase rate (dPB) / dt of the dischargeable output of the secondary battery with respect to the elapse of the discharge time is calculated. In step 105, the rate of increase in dischargeable output (dPB) / dt is compared with a predetermined value B. Here, the predetermined value B is set to zero. (DPB) / dt
Is greater than or equal to the predetermined value B, the discharge has caused an increase in the dischargeable output, and therefore the process returns to step 101 to continue the discharge.

When the rate of increase in the dischargeable output with respect to time is smaller than the predetermined value B, the routine proceeds to step 106, where the charging traveling mode in which the vehicle is traveling while charging the secondary battery is entered. In the charging traveling mode, the vehicle continues traveling by using only the engine as a power source, and the generator motor 1 is driven by a part of the driving force of the engine to charge the secondary battery 11 with the generated power. In step 107, the state of charge SOC of the secondary battery is compared with a predetermined value to determine whether or not the battery is fully charged. If not fully charged, the process returns to step 106 to continue charging.

When the charge amount is larger than the predetermined value and the secondary battery is fully charged, the charging traveling mode is ended and the process returns to step 100. If it is determined in step 100 that the dischargeable output of the secondary battery is smaller than the predetermined value A again, the above control is repeated until the dischargeable output of the secondary battery reaches the fuel consumption performance of the hybrid vehicle to the design value. The discharge traveling mode and the charging traveling mode are repeated.

FIG. 3 is a diagram showing the fuel consumption rate when the temperature of the secondary battery is raised. The horizontal axis represents time, and the vertical axis represents the dischargeable output of the secondary battery and the fuel consumption rate of the vehicle from the start of running.
The time region is a region where the increase rate of the dischargeable output of the secondary battery with respect to time is zero or more. In this region, since the increase rate of the dischargeable output is zero or more, the secondary battery is running while discharging. Regarding the fuel consumption rate in the time region, the temperature rise due to the discharge of the secondary battery increases the dischargeable output of the secondary battery, so that the fuel consumption rate improves with the passage of time. When the increase rate of the dischargeable output of the secondary battery becomes smaller than zero, the time domain is entered.

In the time domain, the vehicle is running while charging the secondary battery. Since the fuel consumption rate in the time domain is running while charging the secondary battery, the charge amount SOC of the secondary battery
Due to the increase in the dischargeable output of the secondary battery due to the increase of, the fuel consumption rate has improved with the passage of time. When the charge amount of the secondary battery is larger than the predetermined value and fully charged, the time zone is entered. Hereinafter, the traveling is performed by repeating the traveling while discharging the secondary battery and the traveling while charging the secondary battery. Then, when the dischargeable output reaches the predetermined value A, it is considered that the secondary battery has reached the predetermined temperature, and the temperature rise is terminated.

The present embodiment is configured as described above, and can quickly raise the temperature of the secondary battery and prevent the dischargeable output from being lowered due to overdischarge. Figure 4
It is the figure which arranged the fuel consumption rate when applying a prior art and the fuel consumption rate when applying this invention. The horizontal pongee shows the time, and the vertical axis shows the average fuel consumption of the vehicle from the start of running. Curve 1 shows the fuel consumption rate when the present invention is applied, and curve 2 shows the fuel consumption rate when the conventional technique is used. The figure shows that the fuel consumption rate is lower when the present invention is applied regardless of the traveling time.

In the present embodiment, the predetermined value B for switching the discharge traveling mode to the charging traveling mode is set to zero, but it is not limited to this and can be changed as necessary. Further, the value may not be set to a constant value, but can be changed in correspondence with the charge amount SOC at full charge, the dischargeable output, and the temperature of the secondary battery, which change when the temperature rises, for example. In this case, finer discharge can be controlled and the fuel consumption rate can be further improved.

In this embodiment, the generator motor 1 and the drive motor 4 are AC motors, but the present invention is not limited to this, and DC motors can be used. When a DC motor is used for the generator motor 1 and the drive motor 4, the inverters 8 and 9 use DC / DC converters instead.
As the roles of the generator motor 1 and the drive motor 4, when the clutch 3 is engaged, the generator motor 1 can be used for propulsion and braking of the vehicle, and the drive motor 4 can be used for engine start and power generation.

Further, as the clutch 3, a dry single plate clutch or a wet multi-plate clutch can be used instead of the powder clutch. In this embodiment, step 105
Constitutes a mode switching means. Step 100
Constitutes a temperature rising end means. Step 104 constitutes an increase rate calculation means.

Next, the second embodiment will be described. The present embodiment is a case where the present invention is applied to a hybrid vehicle equipped with a fuel cell power generation system. FIG. 5 is a diagram showing the configuration of a hybrid vehicle equipped with a fuel cell power generation system. The electric power generated by the fuel cell power generation system 26 is
After the voltage is converted by the DC / DC converter 25, it is converted into alternating current by the inverter 22 to drive the motor 21 and drive the wheels 23 connected to the motor. DC
At the output end of the DC / DC converter 25, the secondary battery 27 and D
The C / DC converter 32 is connected, and the fuel cell power generation system 26 charges the secondary battery and
The auxiliary machine 33 can be driven via the C / DC converter 32. The fuel cell power generation system and the DC / DC converter 25 play the role of the engine in the first embodiment.

When a sufficient driving force cannot be generated by the electric power generated by the fuel cell power generation system 26 alone, or when the fuel consumption rate is low, the secondary battery 27 is discharged and the auxiliary device 33 is discharged.
Also, the motor 21 is driven. The controller 31 controls the operation of the fuel cell power generation system 26, the auxiliary equipment 33, and the charging / discharging of the secondary battery. The controller 31 controls the secondary battery 27 depending on the driving condition of the vehicle.
And the power distribution of the fuel cell power generation system 26 is determined and the vehicle is controlled. The controller 31 has
By discharging the secondary battery, the temperature of the secondary battery is raised until a predetermined dischargeable output is obtained. The control flow is the same as the flowchart of FIG. 2 of the first embodiment except that the engine output is changed to the power generation output of the fuel cell power generation system.

That is, 2 detected by the voltage sensor 16
The charge amount SOC of the secondary battery is calculated from the open voltage value of the secondary battery 27, and the charge amount SOC and the temperature sensor 15 detect 2
The dischargeable output PB of the secondary battery is calculated from the map data based on the temperature value of the secondary battery, and the calculated value is compared with the predetermined value A. When the dischargeable output PB of the secondary battery is smaller than the predetermined value A, the temperature of the secondary battery is low, so it is determined that the fuel consumption performance as the designed value cannot be obtained as a hybrid vehicle, and the battery is discharged to raise the temperature. To control.

In order to discharge, first, the power PV required for driving the vehicle is compared with the dischargeable output PB of the secondary battery,
The power PV required to drive the vehicle is the dischargeable output P of the secondary battery.
When it is larger than B, the secondary battery is output with the dischargeable output PB, and the rest (PV-PB) is output with the power generation of the fuel cell power generation system to control the motor. If the dischargeable output of the secondary battery is greater than the power PV required to drive the vehicle, the secondary battery discharge power PV
Is output to the vehicle drive, the remaining (PB-PV) power is supplied to the auxiliary equipment, and the discharge power from the secondary battery is controlled to become PB. The increase rate (dPB) / dt of the dischargeable output of the secondary battery with respect to the elapse of the discharge time is calculated and compared with a predetermined value B. When (dPB) / dt is greater than or equal to the predetermined value B,
The discharge is continuing because it causes an increase in the dischargeable output.

When the rate of increase in the dischargeable output with respect to time is smaller than the predetermined value B, the secondary battery is controlled to run while running. At this time, the vehicle continues to run using only the fuel cell power generation system as a power source, and charges a part of the generated power to the secondary battery. When the secondary battery is fully charged, the dischargeable output of the secondary battery is again compared with the predetermined value A, and the dischargeable output of the secondary battery is discharged until the fuel consumption performance of the hybrid vehicle reaches the design value. And repeated charging,
The temperature of the secondary battery is raised. Other than that, the configuration is the same as that of the first embodiment, and the detailed description thereof is omitted here. Also in this embodiment, the same effect as that of the first embodiment can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment.

FIG. 2 is a flowchart for explaining a control flow for raising a temperature of a secondary battery in a controller.

FIG. 3 is a diagram showing a fuel consumption rate when the temperature of the secondary battery is raised.

FIG. 4 is a diagram showing a fuel consumption rate when the conventional technique is applied and a fuel consumption rate when the present invention is applied.

FIG. 5 is a diagram showing a second embodiment.

[Explanation of symbols]

1 generator motor (power generation means) 2 engine 3 clutch 4 drive motor 4 5 continuously variable transmission 6 differential 7,23 wheels 8, 9, 22 inverter 10 DC link 11,27 secondary battery 12, 25, 32 DC / DC converter 13,33 Auxiliary equipment 14, 31 controller 21 motor 26 Fuel cell power generation system

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 16, 2001 (2001.8.1)
6)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment.

FIG. 2 is a flowchart for explaining a control flow for raising a temperature of a secondary battery in a controller.

FIG. 3 is a diagram showing a fuel consumption rate when the temperature of the secondary battery is raised.

FIG. 4 is a diagram showing a fuel consumption rate when the conventional technique is applied and a fuel consumption rate when the present invention is applied.

FIG. 5 is a diagram showing a second embodiment.

FIG. 6 is a secondary battery in a parallel hybrid vehicle.
FIG. 3 is a diagram showing a fuel consumption rate of a vehicle with respect to a dischargeable output of
It

FIG. 7: Repeated charging and discharging to raise the temperature of the secondary battery.
Dischargeable output of secondary battery and fuel consumption rate
It is a figure.

[Explanation of symbols] 1 generator motor (power generation means) 2 engine 3 clutch 4 drive motor 4 5 continuously variable transmission 6 differential 7,23 wheels 8, 9, 22 inverter 10 DC link 11,27 secondary battery 12, 25, 32 DC / DC converter 13,33 Auxiliary equipment 14, 31 controller 21 motor 26 Fuel cell power generation system

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI theme code (reference) H02J 7/00 ZHV H02J 7/04 L 7/04 B60K 9/00 EF term (reference) 5G003 AA07 CA11 CB01 DA07 DA13 FA06 GC05 5H030 AA01 AS08 BB01 BB21 FF22 FF41 5H031 AA00 AA01 AA02 AA03 KK03 5H115 PA12 PC06 PG04 PI16 PI18 PI24 PI29 PU02 PU09 PU10 PU22 PU24 PU25 PU29 PV02 PV09 QE01 RB08 RE02 TI16 TR02 SE02 TI02 SE02 TI02

Claims (9)

[Claims] 1. A hybrid vehicle equipped with a secondary battery and a power source capable of charging the secondary battery,
A temperature increase controller for a secondary battery, which discharges the secondary battery when the temperature of the secondary battery is low and raises the temperature, the rate of increase in the dischargeable output of the secondary battery with respect to the elapsed time of discharge. And a mode switching unit, wherein the mode switching unit switches the secondary battery from discharging to charging according to the calculated increasing rate of the dischargeable output. And a temperature rise control device for a secondary battery. 2. A temperature rising end means is provided, and the temperature rising end means compares a dischargeable output at the time of completion of charging of the secondary battery with a predetermined value, and when the dischargeable output is smaller than the predetermined value. The temperature rising control device for a secondary battery according to claim 1, wherein the control is performed so that discharging and charging for raising the temperature of the secondary battery are repeated. 3. The increase rate calculating means calculates a charge amount of the secondary battery, calculates a dischargeable output based on the calculated charge amount and a temperature of the secondary battery, and discharges with respect to time. 2. An increase rate of output is calculated.
Alternatively, the temperature rising control device for the secondary battery according to item 2. 4. The mode switching means compares the calculated increase rate of the dischargeable output with a predetermined value, and discharges the secondary battery when the increase rate of the dischargeable output becomes a predetermined value or less. 4. The temperature rising control device for a secondary battery according to claim 1, wherein the charging control device switches from charging to charging. 5. The temperature rising control device for a secondary battery according to claim 4, wherein the predetermined value changes according to a charge amount of the secondary battery when charging is completed. 6. The method according to claim 4, wherein the predetermined value changes according to the temperature of the secondary battery.
Secondary battery temperature rise control device. 7. The temperature rising control device for a secondary battery according to claim 4, wherein the predetermined value changes in accordance with a dischargeable output when the secondary battery is completely charged. 8. The power source is power generating means driven by an engine, as claimed in claim 1,
A temperature rising control device for a secondary battery according to 3, 4, 5, 6 or 7. 9. The temperature rising controller for a secondary battery according to claim 1, wherein the power source is a fuel cell.