Control method for electric vehicle and control system for electric vehicle

Abstract

This control method for an electric vehicle is for delivering power between a drive motor and a battery and limiting the charge / discharge power of the battery when the battery temperature reaches a predetermined upper limit temperature or when the battery temperature falls below a lower limit temperature that is lower than the upper limit temperature, the method involving: calculating a load transition that represents changes in the load of the battery when traveling on a travel route from the current location of the vehicle to a destination; calculating a temperature transition of the battery on the basis of the load transition and the current battery temperature; heating the battery before the load enters a high load state when the battery temperature is predicted to be lower than the lower limit temperature when the load is transitioning from a low load state to a high load state; and cooling the battery before the load enters the high load state when it is predicted that the battery temperature will reach the upper limit temperature when the load state is the high load state.

Description

Control method for electric vehicle and control system for electric vehicle

[0001] The present invention relates to a control method for an electric vehicle and a control system for an electric vehicle.

[0002] JP4765298B discloses that when it is predicted from the vehicle's travel route that the battery temperature will exceed an appropriate temperature, a pre-planned cooling control is carried out to lower the temperature in advance.

[0003] However, when the battery temperature reaches a predetermined upper limit temperature, the charge / discharge power of the battery is limited to prevent the battery from failing. Also, when the battery temperature falls below a predetermined lower limit temperature, the charge / discharge power of the battery is limited because the battery's charge / discharge capability is reduced. Therefore, if a high load is required on the battery while the charge / discharge power of the battery is limited, the driver may not be able to obtain the input / output power he or she desires.

[0004] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a control method and a control system for an electric vehicle that reduce input / output shortages when a high load is required on the battery.

[0005] According to one aspect of the present invention, there is provided a control method for an electric vehicle that exchanges power between a drive motor and a battery and limits the battery's charge / discharge power when the battery temperature reaches a predetermined upper limit temperature or drops below a lower limit temperature that is lower than the upper limit temperature. This control method estimates, from a travel route from the vehicle's current location to a destination, at least a low-load travel route in which the vehicle travels under a low load on the battery and a high-load travel route in which the vehicle travels under a high load greater than the low load, thereby calculating a load transition that represents changes in the battery load as the vehicle travels along the travel route, and calculates a battery temperature transition based on the load transition and the current battery temperature. If the battery temperature is predicted to be lower than the lower limit temperature when the load transitions from a low-load state to a high-load state, the method heats the battery before the load transitions to a high-load state, and if the battery temperature is predicted to reach the upper limit temperature when the load transitions to a high-load state, the method cools the battery before the load transitions to a high-load state.

[0006] FIG. 1 is a block diagram illustrating the configuration of a vehicle to which the control system for an electric vehicle according to this embodiment is applied. FIG. 2 is a block diagram of the control system for an electric vehicle according to this embodiment. FIG. 3 is a graph showing the relationship between battery temperature and allowable input / output of the battery. FIG. 4 is a graph showing the relationship between the state of charge (SOC) of the battery and the allowable input of the battery. FIG. 5 is a graph showing the relationship between the state of charge (SOC) of the battery and the allowable output of the battery. FIG. 6 is a flowchart (S101-S109) of the process performed when the vehicle enters a high-load output driving route in the control system for an electric vehicle according to this embodiment. FIG. 7 is a flowchart (S110-S121) of the process performed when the vehicle enters a regenerative braking driving route or before the vehicle arrives at a charging point in the control system for an electric vehicle according to this embodiment. FIG. 8 is a time chart showing the process performed when the battery is preheated in advance in anticipation of the vehicle entering a high-load output driving route in the control system for an electric vehicle according to this embodiment. FIG. 9 is a time chart showing the process performed when the battery is precooled in advance in anticipation of the battery temperature reaching an upper limit temperature while the vehicle is traveling on a high-load output driving route in the control system for an electric vehicle according to this embodiment. FIG. 10 is a time chart showing a case where the control system for an electric vehicle according to this embodiment preheats the battery in anticipation of the vehicle entering a regenerative braking travel route. FIG. 11 is a time chart showing a case where the control system for an electric vehicle according to this embodiment precools the battery in anticipation of the battery temperature reaching an upper limit temperature while the vehicle is traveling on a regenerative braking travel route. FIG. 12 is a time chart showing a case where the control system for an electric vehicle according to this embodiment preheats the battery in anticipation of the vehicle arriving at a charging point and charging the battery. FIG. 13 is a time chart showing a case where the control system for an electric vehicle according to this embodiment precools the battery in anticipation of the battery temperature reaching a set temperature while the battery is being charged. FIG. 14 is a flowchart (S201-S215) showing a case where the control system for an electric vehicle according to this embodiment charges the battery and then travels the vehicle. FIG. 15 is a time chart showing a case where the control system for an electric vehicle according to this embodiment travels on a low-load travel route after charging the battery and arrives at a destination.

[0007] [Configuration of Vehicle 100] FIG. 1 is a block diagram illustrating the configuration of a vehicle 100 to which the electric vehicle control system of this embodiment is applied. The vehicle 100 is an electric vehicle. An electric vehicle is a vehicle that has a drive motor (hereinafter simply referred to as motor 4) as a drive source and travels by generating drive force due to torque generated by the motor 4 at one or more wheels. Therefore, electric vehicles include not only so-called electric automobiles but also hybrid vehicles that use both the motor 4 and an engine as a drive source. For example, electric vehicles also include hybrid vehicles that use the motor 4 as a drive source for one of the front or rear wheels and an engine as a drive source for the other wheels. Furthermore, a four-wheel drive vehicle refers to a vehicle that uses four wheels as drive wheels 9. Four-wheel drive vehicles include vehicles that always use four wheels as drive wheels 9, as well as vehicles that can switch between so-called two-wheel drive (front-wheel drive or rear-wheel drive) and four-wheel drive. Furthermore, a four-wheel drive vehicle can control some of its four wheels in conjunction with each other as drive wheels 9, or it can control all four wheels as drive wheels 9 that are driven independently. Therefore, in this embodiment, the electric four-wheel drive vehicle refers to a vehicle 100 that runs by generating driving force due to the torque generated by the motor 4 on some or all of the four wheels.

[0008] 1, the vehicle 100 is an electric four-wheel drive vehicle, but may also be an electric two-wheel drive vehicle with only front wheels or only rear wheels. The vehicle 100 includes a front drive system fds, a rear drive system rds, a battery 1, and a controller 2 (control unit).

[0009] The front drive system fds receives power from the battery 1 and drives the front wheels 9f under the control of the controller 2. The front drive system fds includes a front inverter 3f, a front drive motor 4f, a front reduction gear 5f, a front rotation sensor 6f, a front drive shaft 8f, and front wheels 9f. The subscript f indicates a front-side configuration. The front wheels 9f are a pair of wheels that are relatively forward of the vehicle 100, out of the four wheels equipped on the vehicle 100. The forward direction of the vehicle 100 is a predetermined direction that is formally determined depending on the orientation of the driver's seat, etc. The front drive system fds causes the front wheels 9f to function as drive wheels 9 that generate driving force for the vehicle 100.

[0010] The rear drive system rds receives power from a battery 1 and drives rear wheels 9r under the control of a controller 2. The rear drive system rds is symmetrical to the front drive system fds and includes a rear inverter 3r, a rear drive motor 4r, a rear reduction gear 5r, a rear rotation sensor 6r, a rear drive shaft 8r, and rear wheels 9r. The subscript r indicates a rear-side configuration. The rear wheels 9r are a pair of wheels that are relatively rearward of the vehicle 100 out of the four wheels equipped on the vehicle 100. The rearward direction of the vehicle 100 refers to the direction opposite to the forward direction of the vehicle 100. With the rear drive system rds, the rear wheels 9r function as drive wheels 9 that generate driving force for the vehicle 100.

[0011] The battery 1 is connected to the motor 4 via an inverter 3 and supplies drive power to the motor 4 by discharging. The battery 1 can also be charged by receiving regenerative power from the motor 4. In the front drive system fds, the battery 1 is connected to the front drive motor 4f via a front inverter 3f. Similarly, in the rear drive system rds, the battery 1 is connected to the rear drive motor 4r via a rear inverter 3r.

[0012] The controller 2 is a control device for the vehicle 100 and is a computer comprising a central processing unit (CPU), read-only memory (ROM), random access memory (RAM), an input / output interface (I / O interface), etc. The controller 2 generates control signals for controlling the front drive motor 4f and the rear drive motor 4r based on vehicle variables of the vehicle 100. The vehicle variables are information indicating the operating state or control state of the entire vehicle 100 or of each part constituting the vehicle 100, and can be obtained by detection, measurement, calculation, etc. The vehicle variables include, for example, the accelerator opening APO, longitudinal and lateral G, vehicle speed V, gradient value, steering angle, and wheel speed, as well as the rotational speeds Nmf and Nmr of the motors 4f and 4r, and three-phase AC current, as will be described later. The controller 2 uses these vehicle variables to control the front drive motor 4f and the rear drive motor 4r, respectively.

[0013] The front inverter 3f and the rear inverter 3r convert the DC current supplied from the battery 1 into AC current by turning on / off switching elements in response to drive signals generated by the controller 2, and adjust the current supplied to the front drive motor 4f and the rear drive motor 4r, respectively. In addition, the inverters 3f, 3r inversely convert the AC current generated by the front drive motor 4f and the rear drive motor 4r due to regenerative braking force back into DC current, and adjust the current supplied to the battery 1.

[0014] The front drive motor 4f and the rear drive motor 4r are, for example, three-phase AC motors that generate drive force (torque T) using AC current supplied from the inverter 3 connected to them. The drive force generated by the front drive motor 4f is transmitted to the front wheels 9f via the front reduction gear 5f and the front drive shaft 8f. Similarly, the drive force generated by the rear drive motor 4r is transmitted to the rear wheels 9r via the rear reduction gear 5r and the rear drive shaft 8r. When the front drive motor 4f and the rear drive motor 4r rotate along with the front wheels 9f and the rear wheels 9r, respectively, they generate regenerative braking force and recover the kinetic energy of the vehicle 100 as electrical energy. The front drive motor 4f constitutes a drive source (front drive source) that drives the front wheels 9f. Similarly, the rear drive motor 4r constitutes a drive source (rear drive source) that drives the rear wheels 9r independently of the front wheels 9f.

[0015] The front reduction gear 5f and the rear reduction gear 5r are composed of, for example, multiple gears. Each of these reduction gears 5f, 5r reduces the rotational speed Nm of the motor 4 connected to it and transmits the reduced torque to the drive shaft 8, thereby generating a driving torque or braking torque proportional to the reduction ratio. The front rotation sensor 6f and the rear rotation sensor 6r detect the rotor phase of the motor 4 connected to them and output the detected rotor phase to the controller 2. The controller 2 detects the rotational speed Nmf of the front drive motor 4f based on the output of the front rotation sensor 6f, and the rotational speed Nmr of the rear drive motor 4r based on the output of the rear rotation sensor 6r. The front current sensor 7f and the rear current sensor 7r detect the current flowing through the motor 4 connected to them and output the detected rotor phase to the controller 2. In this embodiment, these current sensors 7f, 7r detect the three-phase AC current of each of the motors 4f, 4r, respectively.

[0016] The vehicle 100 is equipped with various sensors 15 in addition to the front rotation sensor 6f, front current sensor 7f, rear rotation sensor 6r, and rear current sensor 7r described above. The various sensors 15 include, for example, an accelerator opening sensor 15a, an acceleration sensor 15b, a vehicle speed sensor 15c, a gradient sensor, a steering angle sensor, a wheel speed sensor, and the like. The accelerator opening sensor 15a detects the accelerator opening APO, which is the amount of accelerator operation. The acceleration sensor 15b detects the acceleration of the vehicle 100 in the longitudinal and lateral directions, i.e., the longitudinal G and the lateral G. The vehicle speed sensor 15c detects the vehicle speed V of the vehicle 100. The vehicle speed V is the moving speed of the entire body of the vehicle 100, i.e., the vehicle speed. The gradient sensor detects the gradient value, which is the gradient of the road on which the vehicle 100 is traveling. The steering angle sensor detects the steering angle of the steering wheel. The wheel speed sensors detect the wheel speeds of each drive wheel 9. The detected values ​​by the various sensors 15 are input to the controller 2.

[0017] In the vehicle 100, the target drive torque T_req, which is the torque requested by the driver, is distributed to the front wheels 9f and the rear wheels 9r. Therefore, once either the front torque distribution value RTf, which is the torque distribution value RT for the front wheels 9f, or the rear torque distribution value RTr, which is the torque distribution value RT for the rear wheels 9r, is determined, the other is also determined, and as a result, the torque distribution to the front and rear wheels 9f, 9r is also determined. For this reason, in the vehicle 100, the rear torque Tr, which is the torque T of the rear drive motor 4r, is calculated based on the driving state represented by a first parameter such as front and rear G, as will be described later. As a result, the rear torque distribution value RTr becomes calculable, and torque distribution control for the front and rear wheels 9f, 9r is performed by essentially calculating the rear torque distribution value RTr.

[0018] [Configuration of the control system] Fig. 2 is a block diagram of the control system for the electric vehicle of this embodiment. Fig. 3 is a diagram showing the relationship between the temperature of the battery 1 and the input / output characteristics of the battery 1. Fig. 4 is a diagram showing the relationship between the state of charge (SOC) of the battery 1 and the input characteristics of the battery 1. Fig. 5 is a diagram showing the relationship between the state of charge (SOC) of the battery 1 and the output characteristics of the battery 1.

[0019] The control system for an electric vehicle of this embodiment is made up of a navigation device 20, an EV controller 21, a battery controller 22, an air conditioner 23 (HVAC: Heating Ventilation Air Conditioning), a cooling device (chiller 25, radiator 24), and a heater 26.

[0020] The air conditioning device 23 includes an air conditioner heat exchange circuit that circulates a refrigerant (e.g., an alternative chlorofluorocarbon such as HFC134a) that exchanges heat with an air conditioner that conditions the air inside the vehicle cabin. The air conditioner heat exchange circuit includes: a compressor that compresses refrigerant gas and discharges high-temperature, high-pressure compressed refrigerant gas; a condenser that exchanges heat between the compressed refrigerant gas and outside air and cools and condenses the compressed refrigerant gas to form a liquid refrigerant by dissipating the heat of the compressed refrigerant gas into the outside air; an expansion valve that expands the high-pressure liquid refrigerant to form a low-pressure, low-temperature liquid refrigerant; and an evaporator that exchanges heat between the liquid refrigerant and the air inside the vehicle cabin to absorb the heat of the air inside the vehicle cabin and thereby cool the air inside the vehicle cabin and evaporate the liquid refrigerant to form a refrigerant gas.

[0021] A first circulation circuit (not shown) that circulates the refrigerant (water) that cools the battery 1 to the chiller 25, and a second circulation circuit (not shown) that circulates the refrigerant (water) that cools the battery 1 to the radiator 24 are connected in parallel to the battery 1.

[0022] The chiller 25 is, for example, a circuit (not shown) branched from the air conditioner heat exchange circuit and connected to the first circulation circuit, and performs heat exchange between the refrigerant (alternative chlorofluorocarbon) circulating through the branch circuit and the refrigerant (water) circulating through the first circulation circuit. When the chiller 25 does not cool the battery 1, the operation of the compressor (not shown) of the chiller 25 is stopped.

[0023] The vehicle 100 is also equipped with a drive system circulation circuit (not shown) that circulates a refrigerant (water) for cooling the motor 4 and the inverter 3. A radiator 24 is disposed in the drive system circulation circuit, and the radiator 24 exchanges heat between the refrigerant and outside air. A second circulation circuit branches off from the drive system circulation circuit, and the second circulation circuit circulates the refrigerant cooled by the radiator 24 to the battery 1. When the battery 1 is not to be cooled by the radiator 24, an open / close valve (not shown) disposed in the second circulation circuit is closed, or the operation of the circulation pump that circulates the refrigerant is stopped.

[0024] The heater 26 is, for example, a PTC (Positive Temperature Coefficient) heater, and is arranged so as to be in contact with the battery 1 or a heat capacity body in contact with the battery 1 , and heats the battery 1 .

[0025] As described above, the battery 1 supplies power to the motor 4, but also supplies power to the compressor (not shown) of the chiller 25, the circulation pump (not shown) and opening / closing valve (not shown) of the drive system circulation circuit, and the heater 26.

[0026] The navigation device 20 generates map information including information about a driving route from the current location (or departure point) of the vehicle 100 to a destination (or an intermediate point) and outputs the information to the EV controller 21. Information about the current location (departure point) of the vehicle 100 is obtained, for example, by a GPS (Global Positioning System) and is obtained by matching the information with roads on the map information held by the navigation device 20. Destination information is obtained by specifying the destination on the map information through an input operation by the driver. Here, the destination is, for example, the end point of navigation, or the position where the entire vehicle system stops. The driving route information is obtained by the navigation device 20 selecting a route connecting the current location (departure point) and the destination on the map information. The map information (driving route information) includes information about the distance to the destination, information about the positions of the roads that make up the driving route, information about the gradient of the roads, information about the elevation difference, traffic information, etc. Traffic information includes, for example, information on road attributes (general roads, expressways), information on predicted road vehicle speeds (legal speed limits, statistical average vehicle speeds), and information on charging points (location, charger output, attributes (general roads, expressways)).

[0027] The battery controller 22 includes the front inverter 3f and rear inverter 3r, and controls the exchange of power between the battery 1 and the motor 4. When a charger (charging plug) located at a charging point is inserted into a charging plug socket located in the vehicle 100, the battery controller 22 detects the charging plug and supplies the output from the charger to the battery 1, thereby charging the battery 1. The battery controller 22 also detects the state of charge (SOC) and temperature of the battery 1, and outputs this information to the EV controller 21.

[0028] The battery controller 22 monitors the temperature of the battery 1 and determines whether the temperature of the battery 1 exceeds a predetermined upper limit temperature (T ｍａｘ : the upper limit temperature of the battery 1) or the lower limit temperature (T ｍｉｎWhen the temperature of the battery 1 drops below a predetermined set temperature (T １ ), the allowable input [kW] of the battery 1 can be limited. １ ) is the upper limit temperature (T ｍａｘ ) or the upper limit temperature (T ｍａｘ ) and the first intermediate temperature (T ｍｉｄ１ ) is the temperature between

[0029] In addition, when the vehicle system is stopped and the outside air temperature is lower than the above-mentioned lower limit temperature (T ｍｉｎ ) or lower, the temperature of the battery 1 is the lower limit temperature (T ｍｉｎ ) or less. Furthermore, if a high load is applied to the battery 1 for a long period of time, the temperature of the battery 1 may reach the upper limit temperature.

[0030] In addition, in FIG. 3, the upper limit temperature (T ｍａｘ ) and the lower limit temperature (T ｍｉｎ The magnitude of the allowable input / output between the battery 1 and the regenerative braking route corresponds to the output of the battery 1 in the high-load output driving route and the input of the battery 1 in the regenerative braking driving route, which will be described later. Note that although the input and output characteristics of the battery 1 are the same in FIG. 3, they may have different characteristics.

[0031] The battery controller 22 can control the cooling device and the heater 26 so that the temperature of the battery 1 falls within an appropriate temperature range, as will be described later.

[0032] As shown in FIG. 4, the battery controller 22 monitors the charging rate of the battery 1 and determines whether the charging rate (SOC) of the battery 1 reaches a predetermined upper limit (S ｍａｘ If the battery voltage becomes higher than the allowable input [kW] of the battery 1, the allowable input [kW] of the battery 1 is limited to prevent the battery 1 from being overcharged.

[0033] As shown in FIG. 5, the battery controller 22 monitors the charging rate of the battery 1 and determines whether the temperature of the battery 1 reaches a predetermined lower limit (S ｍｉｎIf the charging rate becomes lower than the allowable output [kW] of the battery 1, the charging rate is prevented from becoming zero by limiting the allowable output [kW] of the battery 1.

[0034] The EV controller 21 includes the controller 2. The EV controller 21 receives map information from the navigation device 20, including information on the driving route from the current location (or starting point) to the destination, and estimates low-load driving routes, high-load driving routes (high-load output driving routes, regenerative braking driving routes), and charging points from the map information, and calculates this information. The charging point information includes location information, charger output information, and attribute information (general roads, expressways).

[0035] A low-load driving route is a route on which the vehicle 100 can travel with a low load on the battery 1, for example, by driving the vehicle 100 at a low vehicle speed on a road (e.g., a public road) that has a road gradient (uphill or downhill) lower than a predetermined inclination angle and is substantially flat.

[0036] A high-load output driving route is a route in which the battery 1 supplies power to the motor 4, and is a route on which the vehicle 100 can travel under a high load on the battery 1, such as a road (general road, expressway) where the road gradient is higher than a predetermined inclination angle and continues for a predetermined distance (e.g., 1 km) or more, or a road (particularly an expressway) where the speed limit or average vehicle speed is set at a predetermined speed (e.g., 100 km / s) or more and extends for a predetermined distance (e.g., 1 km) or more.

[0037] A regenerative braking driving route is a route where regenerative power is supplied from the motor 4 to the battery 1, and is, for example, a route where a downhill slope with a road gradient higher than a predetermined inclination angle continues for a predetermined distance (for example, 1 kilometer) or more, or a route where large regenerative braking due to regenerative power is performed on the vehicle 100 when the vehicle 100 is traveling in an area including the boundary between a highway and a general road.

[0038] A charging point is a facility for charging the battery 1 of the vehicle 100, and the battery 1 is in a high load state during charging.

[0039] The EV controller 21 stores information on multiple driving routes acquired in the past, and also stores information on low-load driving routes, high-load output driving routes, regenerative braking driving routes, and charging point information associated with each driving route information.

[0040] The EV controller 21 preferably compares the last input driving route with information on past driving routes, and if there is information on a past driving route that matches the last input driving route information, extracts information on a low-load driving route, information on a high-load output driving route, information on a regenerative braking driving route, and information on charging points that are associated with the information on that driving route.

[0041] Incidentally, there are cases where the travel route from the current location (or starting point) of the vehicle 100 to the destination is known to have a monotonous terrain and the load (input / output) on the battery 1 is known to be approximately constant. In this case, the EV controller 21 can estimate a low-load travel route or a high-load output travel route based on the load on the battery 1 at the current location or the average load on the battery 1 from the starting point to the current location. This reduces the processing load on the EV controller 21.

[0042] The EV controller 21 calculates a load transition that represents the change in the load on the battery 1 when the vehicle 100 travels along the travel route based on information on low-load travel routes, high-load output travel routes, regenerative braking travel routes, and charging point information arranged along the travel route.

[0043] The EV controller 21 calculates the temperature transition of the battery 1 based on the load transition and the current temperature of the battery 1. More specifically, the EV controller 21 predicts the temperature transition of the battery 1 when the vehicle 100 travels a predetermined monitoring distance (e.g., 10 km) from the current location based on the current temperature of the battery 1. Of course, the EV controller 21 may also predict the temperature transition of the battery 1 when the vehicle 100 travels from the current location to the destination.

[0044] The EV controller 21 determines whether the temperature of the battery 1 reaches a lower limit temperature (T ｍｉｎ), the control for heating the battery 1 is executed before the load becomes a high load state.

[0045] That is, as will be described later, the EV controller 21 determines whether the temperature of the battery 1 reaches the lower limit temperature (T ｍｉｎ ), the output deficiency of battery 1 (insufficient driving force of vehicle 100) is reduced by executing control to heat battery 1 before vehicle 100 enters a high-load output driving route.

[0046] The EV controller 21 determines whether the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ) is predicted to be reached, control is executed to cool the battery 1 before the load becomes a high load state.

[0047] That is, the EV controller 21 detects whether the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ), the output deficiency of battery 1 (insufficient driving force of vehicle 100) is reduced by executing control to cool battery 1 before vehicle 100 enters a high-load output driving route.

[0048] As will be described later, the EV controller 21 determines whether the temperature of the battery 1 reaches an upper limit temperature (T ｍａｘ ), control is executed to cool the battery 1 before the vehicle 100 enters the regenerative braking driving route, thereby reducing the input deficiency (regenerative braking deficiency) of the battery 1 and improving the charging rate of the battery 1.

[0049] As will be described later, the EV controller 21 determines whether the state of charge (SOC) of the battery 1 reaches an upper limit (S ｍａｘ When it is predicted that the temperature of the battery 1 will reach the upper limit temperature (T ｍａｘ ) is reached.

[0050] As will be described later, the EV controller 21 determines whether the temperature of the battery 1 reaches a lower limit temperature (T ｍｉｎ ), the battery 1 is heated before the vehicle 100 enters the regenerative braking driving route, thereby reducing the input deficiency (regenerative braking deficiency) of the battery 1.

[0051] As will be described later, the EV controller 21 determines whether the temperature of the battery 1 is below the lower limit temperature (T ｍｉｎ ), the input shortage of battery 1 (charging time of battery 1) is reduced by executing control to heat battery 1 before vehicle 100 arrives at the charging point.

[0052] As will be described later, the EV controller 21 determines whether the temperature of the battery 1 reaches a set temperature (T １ ), control is executed to cool the battery 1 before the vehicle 100 arrives at the charging point, thereby reducing the input shortage of the battery 1 and shortening the charging time of the battery 1.

[0053] The EV controller 21 determines whether the temperature of the battery 1 is below the lower limit temperature (T ｍｉｎ ) and the upper limit temperature (T ｍａｘ ) is controlled to be in an appropriate temperature range lower than the upper limit temperature (T ｍａｘ ) and the lower limit temperature (T ｍｉｎ ) the first intermediate temperature (T ｍｉｄ１ ), cooling of the battery 1 is started, and thereafter, when the temperature of the battery 1 reaches the first intermediate temperature (T ｍｉｄ１ ) and the lower limit temperature (T ｍｉｎ ) the second intermediate temperature ( Ｔｍｉｄ２ ) or less. The EV controller 21 stops cooling the battery 1 when the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ) and the lower limit temperature (T ｍｉｎ ) intermediate temperature (T ｍｉｄ ), cooling of the battery 1 begins, and then, when the temperature of the battery 1 reaches the intermediate temperature (T ｍｉｄ), control may be executed to stop cooling of the battery 1.

[0054] When the outside air temperature is equal to or higher than a predetermined threshold temperature, the EV controller 21 cools the battery 1 using the chiller 25. In this case, the EV controller 21 turns on the compressor of the chiller 25 and closes the open / close valve. Furthermore, when the outside air temperature is lower than the threshold temperature, the EV controller 21 cools the battery 1 using the radiator 24. In this case, the EV controller 21 stops the compressor of the chiller 25 and opens the open / close valve (turns on the circulation pump).

[0055] The EV controller 21 sets the threshold temperature so that the greater the load on the battery 1, the lower the threshold temperature, and conversely, so that the smaller the load, the higher the threshold temperature.

[0056] When the vehicle 100 enters a low-load traveling route and it is predicted that the end point of the low-load traveling route is the destination of the vehicle 100, the EV controller 21 stops cooling the battery 1 regardless of the temperature of the battery 1. This avoids control of cooling the battery 1 by the chiller 25 when the outside air temperature is equal to or higher than the threshold temperature, thereby reducing power consumption.

[0057] Chargers at charging points include slow chargers and rapid chargers. A slow charger has an output voltage of, for example, 100 V AC, and converts this output voltage to 400 V DC via a charger mounted on the vehicle 100 and supplies it to the battery 1. A rapid charger has an output voltage of 400 V DC, and supplies power from this output voltage directly to the battery 1. In this embodiment, it is assumed that the charging point along the driving route is a rapid charger, but a slow charger is also applicable.

[0058] [First control flow] Fig. 6 is a flowchart (S101-S109) when the vehicle 100 enters a high-load output driving route in the control system for an electric vehicle of this embodiment. Fig. 7 is a flowchart (S110-S121) when the vehicle 100 enters a regenerative braking driving route or before the vehicle 100 arrives at a charging point in the control system for an electric vehicle of this embodiment.

[0059] The first control flow is a control flow for when the vehicle 100 is traveling on a low-load traveling route and the battery 1 is heated or cooled before entering a high-load output traveling route or a regenerative braking traveling route, and when the battery 1 is heated or cooled before the vehicle 100 arrives at a charging point. For ease of explanation, the road on which the vehicle 100 first travels is assumed to be a low-load traveling route, but in the present invention, the type of traveling route the vehicle 100 travels before entering a high-load output traveling route or a regenerative braking traveling route, and the type of traveling route the vehicle 100 travels before arriving at a charging point are not important.

[0060] In step S101 , the EV controller 21 acquires from the navigation device 20 information on the travel route from the current location (or starting point) of the vehicle 100 to the destination.

[0061] In step S102, based on the information about the driving route, the EV controller 21 estimates information about a low-load driving route, information about a high-load output driving route, information about a regenerative braking driving route, and information about charging points from the driving route from the current location of the vehicle 100 to a predetermined monitoring distance (e.g., 10 km), and calculates a load transition that represents the change in load on the battery 1 when the vehicle 100 drives the driving route.

[0062] In step S103, the EV controller 21 estimates the temperature transition of the battery 1 when the vehicle 100 travels the monitoring distance based on the load transition and the current temperature of the battery 1. The temperature transition of the battery 1 is calculated based on, for example, the difference between the time integral of the load transition and the heat dissipation amount based on the temperature difference between the battery 1 and the outside air.

[0063] In step S104, the EV controller 21 determines whether the state of charge (SOC) of the battery 1 is lower than the lower limit (Sｍｉｎ If the answer is YES, the process proceeds to "RETURN"; if the answer is NO, the process proceeds to step S105.

[0064] In step S105, the EV controller 21 calculates whether or not the vehicle is entering a high load output travel route. If YES, the process proceeds to step S105, and if NO, the process proceeds to step S110.

[0065] In step S106, the EV controller 21 determines whether the temperature of the battery 1 reaches the lower limit temperature (T ｍｉｎ ) is lower than the predetermined value, it is determined whether the vehicle 100 is predicted to be traveling on a low-load traveling route, and if YES, the process proceeds to step S107, and if NO, the process proceeds to step S108.

[0066] In step S107, the EV controller 21 heats the battery 1 before the vehicle 100 enters the high-load output driving route. ｍｉｎ ), heating of battery 1 is stopped and the process shifts to "RETURN".

[0067] In step S108, the EV controller 21 determines whether the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ), it is determined whether the vehicle 100 is predicted to be traveling on a low-load traveling route, and if YES, the process proceeds to step S109, and if NO, the process proceeds to "RETURN".

[0068] In step S109, the EV controller 21 cools the battery 1 before the vehicle 100 enters the high-load output driving route. ｍｉｎ The timing for starting cooling of the battery 1 is set so that the vehicle 100 enters the high-load output driving route at the timing when the voltage drops to 0 V. Then, cooling of the battery 1 continues even after the vehicle 100 enters the high-load output driving route.

[0069] In step S110, the EV controller 21 determines whether or not the vehicle is entering a regenerative braking travel route. If the determination is YES, the process proceeds to step S111, and if the determination is NO, the process proceeds to step S117.

[0070] In step S111, when the vehicle 100 enters the regenerative braking travel route, the temperature of the battery 1 is lower than the lower limit temperature (T ｍｉｎ ) is predicted to be lower than the predetermined value, the process proceeds to step S112 if the vehicle 100 is traveling on a low-load route, and if the result is YES, the process proceeds to step S112, and if the result is NO, the process proceeds to step S114.

[0071] In step S112, the EV controller 21 sets the temperature of the battery 1 to a lower limit temperature (T ｍｉｎ ) is the total amount of power (total battery heating power) required to heat the battery 1 to the lower limit temperature (T ｍｉｎ If the answer is NO, the process proceeds to step S113. If the answer is YES, the process proceeds to "RETURN." When the vehicle 100 is traveling downhill, the total amount of regenerative power is calculated based on the inclination angle of the downhill slope, the length (distance) of the downhill slope, the predicted vehicle speed on the downhill slope (the predicted torque of the motor 4), and the temperature transition of the battery 1 when the vehicle 100 is traveling downhill.

[0072] In step S113, the EV controller 21 heats the battery 1 before the vehicle 100 enters the regenerative braking driving route. ｍｉｎ ), heating of battery 1 is stopped and the process shifts to "RETURN".

[0073] In step S114, the EV controller 21 determines whether the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ), it is determined whether the vehicle 100 is predicted to be traveling on a low-load traveling route, and if YES, the process proceeds to step S115, and if NO, the process proceeds to "RETURN".

[0074] In step S115, the EV controller 21 sets the temperature of the battery 1 below the lower limit temperature (T ｍｉｎ ) is the total amount of power required to cool the battery 1 down to the lower limit temperature (T ｍｉｎ ), minus the total amount of regenerative power that would be obtained when vehicle 100 travels along the regenerative braking route without cooling battery 1 before vehicle 100 enters the regenerative braking route; if NO, proceed to step S116; if YES, proceed to "RETURN".

[0075] In step S116, the EV controller 21 cools the battery 1 before the vehicle 100 enters the regenerative braking driving route. ｍｉｎ The timing for starting cooling of the battery 1 is set so that the vehicle 100 enters the regenerative braking travel route at the timing when the vehicle temperature drops to 0°C (0°F). Then, cooling of the battery 1 continues even when the vehicle 100 enters the regenerative braking travel route.

[0076] In step S117, the EV controller 21 determines based on the information about the driving route whether or not a charging point exists at the destination of the vehicle, i.e., whether or not the vehicle is heading toward a charging point. If the determination is YES, the process proceeds to step S118; if the determination is NO, the process proceeds to "RETURN."

[0077] In step S118, when the vehicle 100 arrives at the charging point, the temperature of the battery 1 is lower than the lower limit temperature (T ｍｉｎ ) is predicted to be lower than the predetermined value, the vehicle 100 is traveling on a low-load traveling route. If the result is YES, the process proceeds to step S119, and if the result is NO, the process proceeds to step S120.

[0078] In step S119, the EV controller 21 heats the battery 1 before the vehicle 100 arrives at the charging point. ｍｉｎ ), heating of battery 1 is stopped and the process shifts to "RETURN".

[0079] In step S120, the EV controller 21 refers to the charge point information (charger output information) and determines whether the temperature of the battery 1 reaches a set temperature (T １ ), it is determined whether the vehicle 100 is predicted to be traveling on a low-load traveling route, and if YES, the process proceeds to step S121, and if NO, the process proceeds to "RETURN".

[0080] In step S121, the EV controller 21 cools the battery 1 before the vehicle 100 arrives at the charging point. After that, the EV controller 21 continues to cool the battery 1 after the vehicle 100 arrives at the charging point and after charging starts.

[0081] 8 is a time chart for the case where the control system for an electric vehicle according to this embodiment predicts that the vehicle 100 will enter a high-load output driving route and preheats the battery 1. In all figures, including those below, the vehicle speed, temperature of the battery 1, input / output of the battery 1, and SOC of the battery 1, which are indicated by thick dashed lines, are predicted by the EV controller 21.

[0082] At time t0, the vehicle 100 is traveling on a low-load traveling route.

[0083] At time t0, the EV controller 21 determines that the vehicle 100 will enter a high-load output driving route (e.g., a highway) at time t3, and the temperature of the battery 1 (broken line) at that time will be lower than the lower limit temperature (T ｍｉｎ ) is predicted to be lower than

[0084] Therefore, the EV controller 21 starts heating the battery 1 at time t1.

[0085] At time t2, the EV controller 21 detects that the temperature of the battery 1 (solid line) is below the lower limit temperature (T ｍｉｎ) and heating of battery 1 is stopped.

[0086] At time t3, the vehicle 100 enters a high-load output driving route, and the output of the battery 1 (solid line) increases due to the driver's accelerator operation. However, the temperature of the battery 1 drops below the lower limit temperature (T ｍｉｎ ), and the output of the battery 1 is not limited, so the output of the battery 1 (solid line) and the vehicle speed (solid line) required by the driver can be obtained.

[0087] On the other hand, if the battery 1 is not heated in advance (before time t3), the temperature of the battery 1 (dashed line) from time t0 to time t3 is lower than the lower limit temperature (T ｍｉｎ ) is lower than the allowable output (T ) of battery 1. Then, at time t3, when the vehicle enters a high-load output driving route, the output of battery 1 increases, and the temperature of battery 1 (broken line) also begins to increase. However, at time t4, the output of battery 1 reaches the allowable output (T ) of battery 1 shown in FIG. ｍｉｎ Since the battery 1 output (dashed line) and vehicle speed (dashed line) are limited in accordance with the battery 1 output (solid line) and vehicle speed (solid line), they are lower than the battery 1 output (dashed line) and vehicle speed (solid line).

[0088] At time t5, the temperature of the battery 1 (dashed line) reaches the lower limit temperature (T ｍｉｎ ), the output restriction on battery 1 is lifted. However, the output of battery 1 is restricted between time t4 and time t5, and it can be seen that the output of battery 1 (dashed line) and vehicle speed (dashed line) required by the driver cannot be obtained.

[0089] [Second Time Chart] FIG. 9 shows a time chart of the control system for an electric vehicle according to this embodiment, in which the temperature of the battery 1 exceeds the upper limit temperature (T ｍａｘ 10 is a time chart for a case in which the battery 1 is cooled in advance in anticipation of the battery reaching the predetermined temperature.

[0090] At time t0, the vehicle 100 is traveling on a low-load route. The temperature of the battery 1 is an intermediate temperature (T ｍｉｄ ) and the lower limit temperature (T ｍｉｎ ) is the temperature between

[0091] At time t0, the EV controller 21 predicts the temperature transition of the battery 1. At time t2, the vehicle 100 enters a high-load output driving route, causing the output of the battery 1 to increase, which in turn causes the temperature of the battery 1 (dashed line) to rise. At time t3, the chiller 25 (or the radiator 24) starts cooling the battery 1 (dashed line), which causes the rate of increase in the temperature of the battery 1 (the slope of the line indicating the temperature of the battery 1 in FIG. 9) to become slightly slower. However, at time t4, the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ) the output of the battery 1 reaches the allowable output (T ｍａｘ The system predicts that the vehicle speed will be limited according to the vehicle speed limit (the part of the road that is higher than the road speed limit) and the vehicle speed will also be limited.

[0092] Therefore, at time t1, the EV controller 21 starts cooling the battery 1 (solid line) by the chiller 25 (or the radiator 24).

[0093] At time t2, the temperature of the battery 1 reaches the lower limit temperature (T ｍｉｎ ), the vehicle 100 enters the high load output driving route. At this time, the EV controller 21 continues cooling the battery 1 by the chiller 25 (or the radiator 24).

[0094] At time t5, the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ), the output of the battery 1 and the vehicle speed will be the allowable output (T ｍａｘ However, the limitation is imposed after time t5, which is later than time t4. Therefore, it can be seen that the output and vehicle speed of battery 1 required by the driver on a high-load output driving route can be maintained for a longer period of time than in the case where battery 1 is not cooled in advance (before time t2) (dashed line).

[0095] However, in Patent Document 1, the cooling start point (the timing to start operating the cooling fan) is calculated based on the battery temperature and the distance to the point where the charge / discharge rate increases. Therefore, the battery temperature may be rising or falling at this time. If the cooling fan is started when the battery temperature is rising suddenly, its cooling capacity is consumed to suppress the sudden temperature rise. Therefore, to further reduce the temperature after suppressing the temperature rise, the cooling fan is required to have a fairly high cooling capacity. As a result, a large amount of power is consumed, resulting in a problem of worsening power efficiency.

[0096] However, in this embodiment, the battery 1 is cooled to the required temperature before the temperature of the battery 1 rises suddenly due to the high load applied to the battery 1, thereby reducing power consumption more than when cooling of the battery 1 is started immediately after the temperature rises.

[0097] [Third Time Chart] FIG. 10 is a time chart for the case where the battery 1 is preheated in advance in the control system for the electric vehicle of this embodiment in anticipation of the vehicle 100 entering a regenerative braking travel route.

[0098] At time t0, the vehicle 100 is traveling on a low-load traveling route (or a high-load output traveling route).

[0099] At time t0, the EV controller 21 determines that the vehicle 100 will enter a regenerative braking driving route (the vehicle 100 will drive downhill while applying regenerative braking) at time t3, and the temperature of the battery 1 (broken line) at this time will be lower than the lower limit temperature (T ｍｉｎ ) is predicted to be lower than

[0100] Therefore, at time t1, EV controller 21 starts heating battery 1. Note that the power for heating battery 1 (power for heater 26) is provided by battery 1 itself.

[0101] At time t2, the EV controller 21 detects that the temperature of the battery 1 (solid line) is below the lower limit temperature (T ｍｉｎ ) and heating of battery 1 is stopped.

[0102] From time t1 to time t2, the charging rate of battery 1 (solid line) decreases over time compared to the charging rate of battery 1 (dashed line) when battery 1 is not heated in advance (before time t3). Then, since heating of battery 1 is stopped at time t2, the charging rate of battery 1 (solid line) and the charging rate of battery 1 (dashed line) decrease at the same interval.

[0103] At time t3, when the vehicle 100 enters a regenerative braking route, the motor 4 starts to supply regenerative power to the battery 1, and the state of charge (SOC) of the battery 1 increases. The temperature of the battery 1 (broken line) increases to a lower limit temperature (T ｍｉｎ ) and the allowable input (T ｍｉｎ The input to the battery 1 is limited by the voltage Vcc (the portion lower than Vcc).

[0104] Therefore, at time t4, the input (regenerative power) to the battery 1 is the allowable input (T ｍｉｎ ) and the charging rate of battery 1 (dashed line) is lower than the charging rate of battery 1 (solid line), and the difference widens over time.

[0105] At time t5, the temperature of the battery 1 (dashed line) reaches the lower limit temperature (T ｍｉｎ ), the limit on the input to Battery 1 is lifted. As a result, the charging rate of Battery 1 (dashed line) increases at the same rate as the charging rate of Battery 1 (solid line), but does not exceed the charging rate of Battery 1 (solid line).

[0106] The magnitude of the regenerative braking corresponds to the magnitude of the input to the battery 1. Between time t4 and time t5, the magnitude of the regenerative braking (input to battery 1 (dashed line)) when battery 1 is not heated in advance (before time t3) is lower than the magnitude of the regenerative braking (input to battery 1 (solid line)) when battery 1 is heated in advance by heater 26, so the shortfall must be compensated for by, for example, friction braking.

[0107] [Fourth Time Chart] FIG. 11 shows a time chart of the electric vehicle control system according to the present embodiment, in which the temperature of the battery 1 exceeds the upper limit temperature (T ｍａｘ10 is a time chart for a case in which the battery 1 is cooled in advance in anticipation of the battery reaching the predetermined temperature.

[0108] At time t0, the vehicle 100 is traveling on a low-load driving route (or a high-load output driving route). The temperature of the battery 1 is an intermediate temperature (T ｍｉｄ ) and the lower limit temperature (T ｍｉｎ ) is the temperature between

[0109] At time t0, the EV controller 21 predicts the temperature transition and input transition of the battery 1 as follows (1)-(3). (1) At time t2, the vehicle 100 enters a regenerative braking driving route, and the input to the battery 1 increases, causing the temperature of the battery 1 (dashed line) to rise. (2) At time t3, the chiller 25 (or the radiator 24) starts cooling the battery 1 (dashed line), causing the rate of increase in the temperature of the battery 1 (the slope of the line showing the temperature of the battery 1 in FIG. 11) to slow down slightly. (3) At time t4, the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ) reaches the allowable input (T ｍａｘ The regenerative braking is also limited accordingly.

[0110] Therefore, at time t1, the EV controller 21 starts cooling the battery 1 (solid line) by the chiller 25 (or the radiator 24).

[0111] At time t2, the temperature of the battery 1 reaches the lower limit temperature (T ｍｉｎ ), the vehicle 100 enters the regenerative braking driving route. At this time, the EV controller 21 continues cooling the battery 1 by the chiller 25 (or the radiator 24).

[0112] At time t5, the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ) the input of the battery 1 reaches the allowable input (T ｍａｘHowever, the limitation is imposed after time t5, which is later than time t4, so that the regenerative braking (input to battery 1 (solid line)) required by the vehicle on the regenerative braking travel route can be maintained for a longer period of time than in the case where the temperature of battery 1 is not cooled in advance (before time t2) (dashed line).

[0113] In addition, the charging rate of battery 1 (solid line) when battery 1 is pre-cooled is lower than the charging rate of battery 1 (dashed line) when battery 1 is not pre-cooled, because power is supplied to the compressor that circulates the refrigerant in chiller 25 after time t1.

[0114] However, since the input of battery 1 is limited if battery 1 is not pre-cooled at time t4, the charging rate of battery 1 (solid line) is higher than the charging rate of battery 1 (dashed line) between time t4 and time t5.

[0115] After time t5, the charging rate of battery 1 (solid line) and the charging rate of battery 1 (dashed line) progress in the same manner, but the difference between the charging rate of battery 1 (solid line) and the charging rate of battery 1 (dashed line) is maintained.

[0116] Incidentally, the battery 1 provides the power required for cooling the battery 1, i.e., the power of the compressor that supplies the refrigerant to the chiller 25, and the charging rate of the battery 1 reaches a predetermined upper limit (S ｍａｘ When the allowable input [kW] of the battery 1 is limited to protect the battery 1 from deterioration when the state of charge (SOC) of the battery 1 becomes higher than the upper limit (S ｍａｘ ), it is also preferable that the EV controller 21 executes control to cool the battery 1 before the vehicle 100 enters the regenerative braking travel route.

[0117] In this case, for example, when the state of charge (SOC) of the battery 1 reaches the upper limit at time t4 in FIG. 11, the input to the battery 1 is thereafter limited as indicated by the dashed line of "battery input / output" in FIG.

[0118] However, by cooling the battery 1 using the chiller 25, for example, at time t1, and lowering the state of charge (SOC) of the battery 1 before the vehicle 100 enters the regenerative braking driving path, the input to the battery 1 is not restricted until time t5, as shown by the solid line of "Battery Input / Output" in Figure 11.

[0119] Therefore, by lowering the charging rate of the battery 1 before the vehicle 100 enters the regenerative braking travel route, it is possible to reduce the insufficient input to the battery 1 from time t4 to time t5, i.e., the insufficient regenerative braking. Furthermore, since the battery 1 is cooled before the vehicle 100 enters the regenerative braking travel route, the temperature of the battery 1 does not rise above the upper limit temperature (T ｍａｘ ) can be reduced.

[0120] [Fifth Time Chart] FIG. 12 is a time chart for the case where the battery 1 is preheated in anticipation of the vehicle 100 arriving at a charging point and charging the battery 1 in the control system for an electric vehicle of this embodiment.

[0121] At time t0, the vehicle 100 is traveling on a low-load driving route (which may be a high-load output driving route or a regenerative braking driving route) at a predetermined output.

[0122] At time t0, the EV controller 21 determines that the vehicle 100 will arrive at the charging point at time t3 and the output will be zero, but the temperature of the battery 1 (broken line) at that time will be below the lower limit temperature (T ｍｉｎ ) is predicted to be lower than

[0123] Therefore, the EV controller 21 starts heating the battery 1 at time t0.

[0124] At time t1, the EV controller 21 detects that the temperature of the battery 1 (solid line) is below the lower limit temperature (T ｍｉｎ ) and heating of battery 1 is stopped.

[0125] At time t2, the vehicle 100 arrives at the charging point and starts charging (quick charging) the battery 1. This causes the input (solid line) and temperature (solid line) of the battery 1 to increase. Here, the temperature of the battery 1 reaches the lower limit temperature (T ｍｉｎ ), and the input of the battery 1 is not limited, so the input of the battery 1 (solid line) required by the vehicle side can be obtained.

[0126] On the other hand, if the battery 1 is not heated in advance (before time t2), the temperature of the battery 1 (dashed line) from time t0 to time t2 is lower than the lower limit temperature (T ｍｉｎ ) is lower than the allowable input (T ) of battery 1. When charging of battery 1 starts at time t2, the input to battery 1 increases, and the temperature of battery 1 (broken line) also starts to increase. However, at time t3, the input to battery 1 reaches the allowable input (T ) of battery 1 shown in FIG. ｍｉｎ Since the input to battery 1 (dashed line) is limited in accordance with the portion lower than the input to battery 1 (solid line), the input to battery 1 (dashed line) is limited and becomes lower than the input to battery 1 (solid line).

[0127] At time t4, the temperature of the battery 1 (dashed line) reaches the lower limit temperature (T ｍｉｎ ), the restriction on the input to battery 1 is lifted. However, the input to battery 1 is restricted between time t3 and time t4, and the input to battery 1 requested by the vehicle (dashed line) cannot be obtained, which means that the charging time for battery 1 is extended accordingly.

[0128] [Sixth Time Chart] FIG. 13 shows the time chart when the temperature of the battery 1 reaches a set temperature (T １ 10 is a time chart for a case in which the battery 1 is cooled in advance in anticipation of the battery reaching the predetermined temperature.

[0129] At time t0, the vehicle 100 is traveling on a low-load driving route (which may be a high-load output driving route or a regenerative braking driving route). The temperature of the battery 1 is an intermediate temperature (T ｍｉｄ ) and the lower limit temperature (T ｍｉｎ ) is the temperature between

[0130] At time t0, the EV controller 21 predicts the temperature transition and input transition of the battery 1 as shown in the following (1)-(3). (1) At time t2, charging of the battery 1 starts, and the input to the battery 1 increases, causing the temperature of the battery 1 (dashed line) to rise. (2) At time t3, cooling of the battery 1 (dashed line) by the chiller 25 (or the radiator 24) starts, causing the rate of rise in the temperature of the battery 1 (the slope of the line showing the temperature of the battery 1 in FIG. 13) to slow down slightly. (3) At time t4, the temperature of the battery 1 reaches the set temperature (T １ ) reaches the allowable input (T ｍａｘ 1. It is predicted that the charging of battery 1 will be delayed by the amount of the limit (the portion higher than the limit (dashed line)).

[0131] Therefore, at time t1, the EV controller 21 starts cooling the battery 1 (solid line) using the chiller 25 (or the radiator 24).

[0132] At time t2, the temperature of the battery 1 reaches the lower limit temperature (T ｍｉｎ ) the EV controller 21 continues to cool the battery 1 by the chiller 25.

[0133] At time t5, the temperature of the battery 1 reaches the set temperature (T １ ) the input of the battery 1 reaches the allowable input (T １ However, the limit is imposed after time t5, which is later than time t4.

[0134] Therefore, the charging rate of battery 1 (solid line) when battery 1 is cooled in advance (before time t2) is lower at time t2 than the charging rate of battery 1 (dashed line) when battery 1 is not cooled in advance.

[0135] However, between time t4 and time t5, the charge rate of battery 1 (dashed line) increases more slowly than the charge rate of battery 1, and at some point the charge rate of battery 1 (solid line) becomes higher than the charge rate of battery 1 (dashed line).

[0136] After time t5, the charging rate of battery 1 (solid line) and the charging rate of battery 1 (dashed line) increase at the same rate, but the difference between the charging rate of battery 1 (solid line) and the charging rate of battery 1 (dashed line) is maintained.

[0137] Therefore, when the battery 1 is cooled in advance (before time t2), the charging rate of the battery 1 (solid line) reaches full charge at time t6, and when the battery 1 is not cooled in advance, the charging rate of the battery 1 (dashed line) reaches full charge (S １ Here, "fully charged" means that the charging rate of the battery 1 has reached a predetermined charging rate, or a predetermined time has elapsed since the start of charging.

[0138] [Second Control Flow] FIG. 14 is a flow chart (S201-S215) of the control system for an electric vehicle according to this embodiment when the battery 1 is charged and the vehicle then travels.

[0139] Here, when the temperature of the battery 1 reaches or exceeds the first intermediate temperature, the battery 1 is cooled, and then when the temperature of the battery 1 reaches or exceeds the second intermediate temperature (T ｍｉｄ２ ) or lower, cooling is stopped. The battery 1 is cooled by the chiller 25 or the radiator 24; when the outside air temperature is lower than the threshold temperature, the battery 1 is cooled by the radiator 24, and when the outside air temperature is equal to or higher than the threshold temperature, the battery 1 is cooled by the chiller 25. The threshold temperature is set to be lower as the load on the battery 1 predicted from the load transition (information on the driving route) increases, and conversely, it is set to be higher as the load on the battery 1 predicted from the load transition (information on the driving route) decreases. Here, the magnitude of the load is predicted based on, for example, traffic information (load transition) at a predetermined monitoring distance (for example, 10 km) ahead from the vehicle 100, or information on the gradient of the road at the monitoring distance ahead (load transition). The threshold temperature when the load on the battery 1 is high is set to be the second intermediate temperature (T ｍｉｄ２ ), and the threshold temperature when the load on the battery 1 is low is lower than the set temperature (T １ ) is assumed to be higher than

[0140] In step S201, the battery controller 22 detects that a charger (charging plug) at a charging point has been inserted into a charging plug socket arranged on the vehicle 100, and starts charging the battery 1.

[0141] In step S202, the EV controller 21 determines whether the temperature of the battery 1 has risen to an intermediate temperature (T ｍｉｄ１ If the answer is YES, the process proceeds to step S203, and if the answer is NO, the process proceeds to step S204.

[0142] In step S203, the EV controller 21 determines whether the threshold temperature is equal to or lower than the first intermediate temperature (T ｍｉｄ１ ), the battery 1 is cooled by the chiller 25.

[0143] In step S204, the EV controller 21 determines whether the temperature of the battery 1 is equal to or lower than the set temperature (T １ If the answer is YES, the process proceeds to step S205, and if the answer is NO, the process proceeds to step S206.

[0144] In step S205, the EV controller 21 (battery controller 22) determines whether the temperature of the battery 1 is equal to or lower than the set temperature (T １ ) is limited so that the input of battery 1 does not exceed the

[0145] In step S206, the EV controller 21 determines whether charging of the battery 1 is complete, i.e., whether the charging rate of the battery 1 has reached full charge. If the answer is YES, the EV controller 21 proceeds to step S207; if the answer is NO, the EV controller 21 remains in step S206.

[0146] In step S207, the EV controller 21 (battery controller 22) stops the input to the battery 1, and executes steps S101, S102, and S103 shown in FIG.

[0147] In step S208, the EV controller 21 determines whether the vehicle 100 will enter a low-load driving route after the charging point. If YES, the EV controller 21 proceeds to step S209, and if NO, the EV controller 21 proceeds to step S213.

[0148] In step S209, the EV controller 21 determines whether the end point of the low-load traveling route is the destination of the vehicle 100. If YES, the EV controller 21 proceeds to step S210, and if NO, the EV controller 21 proceeds to step S215.

[0149] In step S210, the EV controller 21 sets the threshold temperature to a temperature corresponding to a low load (for example, a temperature higher than the set temperature (T1)) because the load on the battery 1 has shifted from a high load state to a low load state as a result of the vehicle 100 entering a low load driving route. ｍｉｄ１ ), the cooling of the battery 1 is switched from the chiller 25 to the radiator 24 .

[0150] In step S211, the EV controller 21 determines whether the temperature of the battery 1 is equal to or lower than the second intermediate temperature (T ｍｉｄ２ If the answer is YES, the process proceeds to step S212, and if the answer is NO, the process remains in step S211.

[0151] In step S212, the EV controller 21 stops the cooling of the battery 1 by the radiator 24. In this case, the second valve is closed to stop the circulation of the refrigerant between the radiator 24 and the battery 1. The radiator 24 continues to operate until the entire system of the vehicle 100 is shut down.

[0152] In step S213, the EV controller 21 determines whether the threshold temperature is equal to or lower than the second intermediate temperature (T ｍｉｄ２ ), the battery 1 continues to be cooled by the chiller 25.

[0153] In step S214, the EV controller 21 determines whether the temperature of the battery 1 has become equal to or lower than the second intermediate temperature. If YES, the EV controller 21 proceeds to step S215, and if NO, the EV controller 21 proceeds to step S214.

[0154] In step S215, the EV controller 21 stops the cooling of the battery 1 by the chiller 25. In this case, the compressor of the chiller 25 is stopped.

[0155] In the above flowchart, battery 1 is charged from S201 to S206, but there are no particular restrictions on the state of vehicle 100 before step S208, and the control can also be applied to control of entering a low-load driving route after driving a high-load output driving route or a regenerative braking driving route (steps S208-S215).

[0156] [Seventh Time Chart] FIG. 15 is a time chart for the case where the vehicle 100 travels along a low-load travel route and arrives at a destination after charging the battery 1 in the control system for an electric vehicle of this embodiment.

[0157] Before time t0, the temperature of the battery 1 is, for example, an initial temperature (T ０ :Second intermediate temperature (T ｍｉｄ２ ), the charging rate of the battery 1 is at an initial value (a value lower than the charging rate when fully charged), and the vehicle 100 is stopped at a charging point.

[0158] At time t0, the EV controller 21 (battery controller 22) starts charging the battery 1, and the input to the battery 1, the temperature of the battery 1, and the state of charge (SOC) of the battery 1 increase.

[0159] At time t1, the EV controller 21 determines whether the threshold temperature is equal to the second intermediate temperature (T ｍｉｄ２ ), the temperature of the battery 1 is set to a value lower than the first intermediate temperature (T ｍｉｄ１ ), the chiller 25 starts cooling the battery 1.

[0160] At time t2, the EV controller 21 (battery controller 22) detects that the temperature of the battery 1 is equal to or lower than the set temperature (T １ ) the input to battery 1 is limited.

[0161] Between time t0 and time t3, before time t0 (before charging), and from after time t3 until just after the vehicle 100 starts traveling (just after charging), the EV controller 21 predicts, from information about the traveling route, etc., whether the vehicle 100 will travel a low-load traveling route after charging the battery 1 and whether the end point of that route will be the destination.

[0162] At time t3, when the charging rate of the battery 1 reaches full charge, the EV controller 21 (battery controller 22) stops the input to the battery 1 and completes the charging. At this time, if the vehicle 100 is traveling on a low-load traveling route, the threshold temperature is set to the set temperature (T １ ), the cooling of the battery 1 by the chiller 25 is stopped and the cooling of the battery 1 is switched to the cooling by the radiator 24. Furthermore, when the end point of the low-load traveling route is the destination, the cooling of the battery 1 by the chiller 25 and the cooling of the battery 1 by the radiator 24 are not performed. In this case, the temperature of the battery 1 (solid line) is set to a temperature higher than the initial temperature (T ０ ) decreases monotonically.

[0163] When the end point of the low-load travel route is not the destination, the battery 1 is cooled by the radiator 24 and the temperature of the battery 1 (dashed line) decreases at a faster rate than the temperature of the battery 1 (solid line).

[0164] At time t4, the temperature of the battery 1 reaches the second intermediate temperature (T ｍｉｄ２ ), the cooling of the battery 1 by the radiator 24 stops, and thereafter, the initial temperature (T ０ ) decreases monotonically.

[0165] After time t3, when the vehicle 100 travels on a high-load output travel route, the chiller 25 continues to cool the battery 1 even after time t3, but the temperature of the battery 1 does not reach the second intermediate temperature (T ｍｉｄ２ ) or less, cooling of the battery 1 by the chiller 25 is stopped.

[0166] Therefore, when battery 1 provides the power for the compressor of chiller 25, the charge rate of battery 1 (dashed line) between time t3 and time t4 decreases by a larger amount than the charge rate of battery 1 (dashed line) when the compressor is stopped at time t3, due to the amount of power supplied to the compressor.

[0167] Since the compressor stops at time t4, the charging rate of Battery 1 (dashed line) decreases in the same manner as the charging rate of Battery 1 (solid line), but the charging rate of Battery 1 (dashed line) never becomes higher than the charging rate of Battery 1 (solid line).

[0168] As described above, if it is predicted that the vehicle will travel on a low-load driving route after charging battery 1, the power consumption of battery 1 can be reduced by stopping the cooling of battery 1 by chiller 25 when charging of battery 1 is complete.

[0169] The above time chart explains a case where, after charging the battery 1, the vehicle 100 travels on a low-load driving route, and the end point of the low-load driving route is the destination of the vehicle 100. However, the time chart can also be applied to temperature control of the battery 1 when the vehicle 100 travels on a high-load output driving route or a regenerative braking driving route, and then enters a low-load driving route (time t3), and the end point of the low-load driving route is the destination of the vehicle 100.

[0170] [Effects of this embodiment] According to the control method for an electric vehicle of this embodiment, power is exchanged between the drive motor (motor 4) and the battery 1, and the temperature of the battery 1 is controlled to be lower than a predetermined upper limit temperature (T ｍａｘ ) or when the upper limit temperature (T ｍａｘ ) lower than the lower limit temperature (T ｍｉｎ ) when the battery temperature becomes lower than the lower limit temperature (T), the method for controlling an electric vehicle includes estimating, from a travel route from the current location of the vehicle 100 to a destination, a low-load travel route in which the vehicle 100 travels with at least a low load on the battery 1, and a high-load travel route in which the vehicle 100 travels with a high load that is greater than the low load, thereby calculating a load transition that represents a change in the load on the battery 1 when the vehicle 100 travels along the travel route, calculating a temperature transition of the battery 1 based on the load transition and the current temperature of the battery 1, and calculating a temperature when the temperature of the battery 1 becomes lower than the lower limit temperature (T ｍｉｎ ), the battery 1 is heated before the load becomes a high-load state, and when the temperature of the battery 1 is predicted to reach an upper limit temperature when the load is in a high-load state, the battery 1 is cooled before the load becomes a high-load state.

[0171] By the above method, the temperature of the battery 1 is set to the lower limit temperature (T ｍｉｎWhen the load of the battery 1 is shifted from a low load state to a high load state in a state where the temperature is lower than the upper limit temperature (T), the shortage of input / output of the battery 1 is reduced by heating the battery 1 before the load of the battery 1 is shifted to a high load state. ｍａｘ ) can be reduced by cooling the battery 1 before the load on the battery 1 shifts to a high load state. Therefore, it is possible to reduce the input / output shortage when a high load is required on the battery 1.

[0172] In this embodiment, the temperature of the battery 1 is the lower limit temperature (T ｍｉｎ ) and it is predicted that the load of the battery 1 will not subsequently shift to a high load state, the battery 1 is not heated and the temperature of the battery 1 is ｍｉｎ ) and it is predicted that the load on the battery 1 will not subsequently shift to a high load state, the battery 1 is not cooled.

[0173] With the above method, even if the input / output of battery 1 is restricted when the load on battery 1 is high, if the load on battery 1 is not high, there is no need to heat or cool battery 1, and power consumption can be reduced accordingly.

[0174] In this embodiment, past low-load driving routes and high-load driving routes calculated using past map information that has the same driving route as the map information representing the driving route from the current location of vehicle 100 to the destination are extracted as the current low-load driving routes and high-load driving routes.

[0175] The above method makes it possible to estimate low-load and high-load travel routes in a simple manner while reducing the processing load (on the EV controller 21).

[0176] In this embodiment, the high-load driving route includes a high-load output driving route in which the battery 1 supplies power to the drive motor (motor 4), and the low-load driving route and the high-load output driving route are estimated from map information representing the driving route from the current location of the vehicle 100 to the destination.

[0177] By using the above method, if it is known that the road conditions from the departure point to the destination of the vehicle 100 are monotonous, it is possible to easily estimate a low-load driving route and a high-load output driving route without using map information.

[0178] In this embodiment, the map information includes information on the locations of the roads that make up the driving route, information on the gradient of the road, and information on the predicted vehicle speed of the road, and in the map information, portions of the road with an uphill gradient that continues for more than a predetermined distance and portions where the predicted vehicle speed is greater than a predetermined speed are estimated to be high-load output driving routes.

[0179] The above method makes it possible to estimate a high-load output driving route with high accuracy based on map information.

[0180] In this embodiment, the high-load driving route includes a high-load output driving route in which the battery 1 supplies power to the drive motor (motor 4), and the low-load driving route and the high-load output driving route are estimated based on the load at the current location or the load from the starting point of the vehicle 100 to the current location.

[0181] By using the above method, if it is known that the road conditions from the departure point to the destination of the vehicle 100 are monotonous, it is possible to easily estimate a low-load driving route and a high-load output driving route without using map information.

[0182] In this embodiment, the high-load travel route includes a regenerative braking travel route in which the vehicle 100 is braked while regenerative power is supplied from the drive motor (motor 4) to the battery 1, and when the vehicle 100 enters the regenerative braking travel route, the temperature of the battery 1 is lower than the lower limit temperature (T ｍｉｎ ), the battery 1 is heated before the vehicle 100 enters the regenerative braking travel route, and the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ), the battery 1 is cooled before the vehicle 100 enters the regenerative braking travel route.

[0183] By the above method, the temperature of the battery 1 is set to the lower limit temperature (T ｍｉｎ) when the vehicle 100 enters the regenerative braking travel route, the insufficient input of the battery 1 is reduced by heating the battery 1 before the vehicle 100 enters the regenerative braking travel route, and when the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ) can be reduced by cooling the battery 1 before the vehicle 100 enters the regenerative braking travel route. Therefore, it is possible to reduce the input shortage when the input of regenerative power to the battery 1 is required.

[0184] In this embodiment, the regenerative braking driving route is estimated from map information that represents the driving route from the current location of vehicle 100 to the destination. The map information includes information on the positions of the roads that make up the driving route, information on the gradient of the road, and information on the predicted vehicle speed of the road. In the map information, a portion of the road with a downhill gradient that continues for more than a predetermined distance, or a portion where the predicted vehicle speed transitions from an area where the speed is high to an area where the speed difference is lower than a predetermined value, is estimated to be the regenerative braking driving route.

[0185] The above method makes it possible to estimate a regenerative braking travel route with high accuracy using map information.

[0186] In this embodiment, the temperature of the battery 1 before the vehicle 100 enters the regenerative braking travel route is the lower limit temperature (T ｍｉｎ ), the temperature of the battery 1 is lower than the lower limit temperature (T ｍｉｎ ) is the total amount of power (total battery heating power) required to heat the battery 1 to the lower limit temperature (T ｍｉｎ ), the total amount of regenerative power obtained when the vehicle 100 travels on the regenerative braking travel route after heating the battery 1 to the lower limit temperature (T ｍｉｎ ), the temperature of the battery 1 is higher than the lower limit temperature (T ｍｉｎ) is the total amount of power required to cool the battery 1 down to the lower limit temperature (T ｍｉｎ ) and the total amount of regenerative power obtained when vehicle 100 travels along the regenerative braking travel route after being cooled to the regenerative braking level, minus the total amount of regenerative power obtained when vehicle 100 travels along the regenerative braking travel route without cooling battery 1 before vehicle 100 enters the regenerative braking travel route (increase in total amount of regenerative power), cooling of the battery before the vehicle enters the regenerative braking travel route is not performed.

[0187] The above method makes it possible to avoid a situation in which the charge rate of battery 1 after vehicle 100 has passed through a regenerative braking route becomes lower than the charge rate of battery 1 before vehicle 100 entered the regenerative braking route.

[0188] In this embodiment, the battery 1 provides the power required for cooling the battery 1, and the state of charge (SOC) of the battery 1 is lower than a predetermined upper limit value (S ｍａｘ ), when the charging power (input) of the battery 1 is limited when the charging rate (SOC) of the battery 1 reaches the upper limit value (S ｍａｘ ), the battery 1 is cooled before the vehicle 100 enters the regenerative braking travel route.

[0189] By using the above method, the battery 1 is discharged to supply power to cool the battery 1 before the vehicle 100 enters the regenerative braking travel route, thereby reducing the insufficient input to the battery 1, i.e., the insufficient regenerative braking. Furthermore, since the battery 1 is cooled before the vehicle 100 enters the regenerative braking travel route, the temperature of the battery 1 does not exceed the upper limit temperature (T ｍａｘ ) can be reduced.

[0190] In this embodiment, the charging rate of the battery 1 is set to a predetermined lower limit (S ｍｉｎ ) or more, heating and cooling of the battery 1 can be performed, and the charging rate is set to a lower limit (S ｍｉｎ ) heating and cooling of the battery 1 cannot be performed.

[0191] The above method can prevent the battery 1 from running out while the vehicle 100 is traveling.

[0192] In this embodiment, a charging point where the battery 1 can be charged is further estimated along the travel route, and when the vehicle 100 reaches the charging point and charges the battery 1, the temperature of the battery 1 is lower than the lower limit temperature (T ｍｉｎ ), the battery 1 is heated before the vehicle 100 arrives at the charging point, and when the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ , set temperature (T １ )) is predicted to arrive at the charging point, the battery 1 is cooled before the vehicle 100 arrives at the charging point.

[0193] By the above method, the temperature of the battery 1 is set to the lower limit temperature (T ｍｉｎ ) is lower than the upper limit temperature (T ｍａｘ , set temperature (T １ The shortage of input / output of the battery 1 due to the vehicle 100 reaching the charging point can be reduced by cooling the battery 1 before the vehicle 100 arrives at the charging point. Therefore, the shortage of input when the input of charging power to the battery 1 is required can be reduced, and the charging time can be shortened.

[0194] In this embodiment, the low-load travel route and charging points are estimated from map information that indicates the travel route from the current location of the vehicle 100 to the destination.

[0195] The above method makes it possible to reliably extract low-load driving routes and charging points from map information.

[0196] In this embodiment, the temperature of the battery 1 is the upper limit temperature (T ｍａｘ , set temperature (T １ ) and the lower limit temperature (T ｍｉｎ ) intermediate temperature (T ｍｉｄ , the first intermediate temperature (T ｍｉｄ１ When the temperature of the battery 1 reaches the intermediate temperature (T ｍｉｄ , second intermediate temperature (Tｍｉｄ２ When the temperature of the battery 1 becomes lower than the intermediate temperature (T ｍｉｄ , second intermediate temperature (T ｍｉｄ２ When the vehicle 100 starts traveling on a low-load traveling route in a state where the temperature is higher than 100°C, and the end point of the low-load traveling route is predicted to be the destination, cooling of the battery 1 is stopped.

[0197] By using the above method, it is determined that there will be no sudden temperature rise again and the cooling of the battery 1 is stopped. ｍｉｄ , second intermediate temperature (T ｍｉｄ２ This allows for a reduction in power consumption compared to when cooling of the battery 1 is stopped when the battery temperature drops below 100°C.

[0198] In this embodiment, when the vehicle 100 is equipped with a chiller 25 and a radiator 24 capable of cooling the battery 1, the chiller 25 cools the battery 1 when the outside air temperature is above a predetermined threshold temperature, and the radiator 24 cools the battery 1 when the outside air temperature is below the threshold temperature, and the threshold temperature is set to be lower as the load predicted from the load transition increases, and higher as the load predicted from the load transition decreases.

[0199] The power consumption of the compressor (not shown) of the chiller 25 is higher than that of the circulation pump (not shown) that circulates the refrigerant through the radiator 24. Therefore, by using the above method, the radiator 24 can be given priority over the chiller 25 in cooling the battery 1 when the load is low, thereby reducing the power consumption of the entire system.

[0200] According to the control system for an electric vehicle of this embodiment, a drive motor (motor 4), a battery 1 that exchanges power between the drive motor (motor 4), and a battery 2 that controls the temperature of the battery 1 to a predetermined upper limit temperature (T ｍａｘ ) or when the temperature of the battery 1 reaches the upper limit temperature (T ｍａｘ ) lower than a predetermined lower limit temperature (T ｍｉｎand a control unit (EV controller 21) that limits the charge / discharge power of the battery 1 when the battery temperature drops below a lower limit temperature (T), wherein the control unit (EV controller 21) estimates, from a travel route from the current location of the vehicle 100 to a destination, a low-load travel route in which the vehicle 100 travels with at least a low load on the battery 1, and a high-load travel route in which the vehicle 100 travels with a high load that is greater than the low load, thereby calculating a load transition that represents a change in the load on the battery 1 when the vehicle 100 travels along the travel route, calculates a temperature transition of the battery 1 based on the load transition and the current temperature of the battery 1, and calculates a temperature transition of the battery 1 when the temperature of the battery 1 drops below a lower limit temperature (T) when the load transitions from a low-load state to a high-load state. ｍｉｎ ), the battery 1 is heated before the load becomes high, and when the load is in the high load state, the temperature of the battery 1 is lower than the upper limit temperature (T ｍａｘ ) is predicted to be reached, the battery 1 is cooled before the load becomes a high load state.

[0201] With the above configuration, the temperature of the battery 1 is lower than the lower limit temperature (T ｍｉｎ When the load of the battery 1 is shifted from a low load state to a high load state in a state where the temperature is lower than the upper limit temperature (T), the shortage of input / output of the battery 1 is reduced by heating the battery 1 before the load of the battery 1 is shifted to a high load state. ｍａｘ ) can be reduced by cooling the battery 1 before the load on the battery 1 shifts to a high load state. Therefore, it is possible to reduce the input / output shortage when a high load is required on the battery 1.

[0202] Although the embodiments of the present invention have been described above, the above embodiments merely illustrate some of the application examples of the present invention, and the technical scope of the present invention is not intended to be limited to the specific configurations of the above embodiments. Furthermore, the above embodiments can be combined as appropriate.

Claims

1. A control method for an electric vehicle, which exchanges electric power between a drive motor and a battery, and limits charging / discharging power of the battery when the temperature of the battery reaches a predetermined upper limit temperature or falls below a lower limit temperature that is lower than the upper limit temperature, a low-load driving route along which the vehicle travels with a low load on the battery and a high-load driving route along which the vehicle travels with a high load that is greater than the low load, based on a driving route from the current location of the vehicle to the destination; and a load transition that indicates a change in the load on the battery when the vehicle travels along the driving route. calculating a temperature transition of the battery based on the load transition and the current temperature of the battery; heating the battery before the load transitions to the high-load state when it is predicted that the temperature of the battery will be lower than the lower limit temperature when the load transitions from the low-load state to the high-load state; cooling the battery before the load enters the high-load state when it is predicted that the temperature of the battery will reach the upper limit temperature when the load is in the high-load state; a control method for an electric vehicle, in which, when the battery is heated, the battery is heated so that the temperature reaches the lower limit temperature before the load transitions to the high-load state, and heating of the battery is stopped when the battery reaches the lower limit temperature before the load transitions to the high-load state.

2. not heating the battery when the temperature of the battery is lower than the lower limit temperature and it is predicted that the load on the battery will not subsequently transition to the high load state; 2. The method for controlling an electric vehicle according to claim 1, wherein the battery is not cooled when the temperature of the battery is higher than the lower limit temperature and it is predicted that the load on the battery will not subsequently shift to the high load state.

3. 2. The control method for an electric vehicle according to claim 1, wherein the past low-load travel route and the past high-load travel route are calculated using map information representing the travel route from the current location of the vehicle to the destination and past map information in which the travel route is the same, and are extracted as the current low-load travel route and the current high-load travel route.

4. the high-load driving route includes a high-load output driving route in which the battery supplies electric power to the drive motor; The method for controlling an electric vehicle according to claim 1 , wherein the low-load travel route and the high-load output travel route are estimated from map information representing the travel route from the current location of the vehicle to the destination.

5. the map information includes information on the positions of roads constituting the travel route, information on gradients of the roads, and information on predicted vehicle speeds on the roads; 5. The method for controlling an electric vehicle according to claim 4, wherein a portion of the map information where the road with the uphill gradient continues for a predetermined distance or more and a portion where the predicted vehicle speed is equal to or greater than a predetermined speed are estimated to be the high load output travel route.

6. the high-load driving route includes a high-load output driving route in which the battery supplies electric power to the drive motor; The method for controlling an electric vehicle according to claim 1 , wherein the low-load travel route and the high-load output travel route are estimated based on the load at the current location or the load from a departure point of the vehicle to the current location.

7. the high-load travel route includes a regenerative braking travel route in which the vehicle is braked while regenerative power is supplied from the drive motor to the battery, When the temperature of the battery when the vehicle enters the regenerative braking travel route is lower than the lower limit temperature, the battery is heated before the vehicle enters the regenerative braking travel route; 2. The control method for an electric vehicle according to claim 1, wherein, when it is predicted that the temperature of the battery will reach the upper limit temperature while the vehicle is traveling on the regenerative braking travel route, the battery is cooled before the vehicle enters the regenerative braking travel route.

8. Estimating the regenerative braking travel route from map information representing the travel route from the current location of the vehicle to the destination; the map information includes information on the positions of roads constituting the driving route, information on the gradients of the roads, and information on predicted vehicle speeds on the roads; 8. The method for controlling an electric vehicle according to claim 7, wherein a portion of the map information where the road having the downhill gradient continues for a predetermined distance or more, or a portion where the predicted vehicle speed transitions from a region where the predicted vehicle speed is high to a region where the predicted vehicle speed is lower by a predetermined speed difference or more, is estimated to be the regenerative braking travel route.

9. When the temperature of the battery before the vehicle enters the regenerative braking travel route is lower than the lower limit temperature, and it is predicted that the total amount of power required to heat the temperature of the battery to the lower limit temperature is higher than the difference obtained by subtracting the total amount of regenerative power obtained when the vehicle travels on the regenerative braking travel route without heating the battery before the vehicle enters the regenerative braking travel route from the total amount of regenerative power obtained when the vehicle travels on the regenerative braking travel route after heating the battery to the lower limit temperature, heating the battery before the vehicle enters the regenerative braking travel route is not performed, 8. The control method for an electric vehicle according to claim 7, wherein, when the temperature of the battery before the vehicle enters the regenerative braking travel route is higher than the lower limit temperature, if it is predicted that a total amount of power required to cool the temperature of the battery to the lower limit temperature is higher than a difference obtained by subtracting the total amount of regenerative power that is obtained when the vehicle travels on the regenerative braking travel route without cooling the battery before the vehicle enters the regenerative braking travel route from the total amount of regenerative power that is obtained when the vehicle travels on the regenerative braking travel route without cooling the battery before the vehicle enters the regenerative braking travel route.

10. In a case where the battery provides the power required for cooling the battery and the charging power of the battery is limited when the charging rate of the battery reaches a predetermined upper limit value, 8. The control method for an electric vehicle according to claim 7, wherein, when the charging rate of the battery is predicted to reach the upper limit value while the vehicle is traveling on the regenerative braking travel route, the battery is cooled before the vehicle enters the regenerative braking travel route.

11. When the charging rate of the battery is equal to or higher than a predetermined lower limit, heating and cooling of the battery can be performed; The method for controlling an electric vehicle according to claim 1 , wherein heating and cooling of the battery are disabled when the charging rate is lower than the lower limit.

12. further estimating charging points along the travel route where the battery can be charged; heating the battery before the vehicle arrives at the charging point if it is predicted that the temperature of the battery will be lower than the lower limit temperature when the vehicle arrives at the charging point to charge the battery; 2. The control method for an electric vehicle according to claim 1, wherein, if it is predicted that the temperature of the battery will reach the upper limit temperature while the battery is being charged at the charging point, the battery is cooled before the vehicle arrives at the charging point.

13. The method for controlling an electric vehicle according to claim 12, wherein the charging point is estimated from map information representing the travel route from the current location of the vehicle to the destination.

14. When the temperature of the battery reaches or exceeds an intermediate temperature between the upper limit temperature and the lower limit temperature, the battery is cooled, and when the temperature of the battery falls below the intermediate temperature, the cooling of the battery is stopped, 2. The control method for an electric vehicle according to claim 1, wherein cooling of the battery is stopped when the vehicle starts traveling on the low-load traveling route with the temperature of the battery higher than the intermediate temperature and when it is predicted that the end point of the low-load traveling route is the destination.

15. In a case where the vehicle is equipped with a chiller and a radiator capable of cooling the battery, When the temperature of the outside air is equal to or higher than a predetermined threshold temperature, the battery is cooled by the chiller, and when the temperature of the outside air is lower than the threshold temperature, the battery is cooled by the radiator; 2. The control method for an electric vehicle according to claim 1, wherein the threshold temperature is set to be lower as the load predicted from the load transition increases, and the threshold temperature is set to be higher as the load predicted from the load transition decreases.

16. A drive motor; a battery that exchanges power with the drive motor; a control unit that limits charging / discharging power of the battery when a temperature of the battery reaches a predetermined upper limit temperature or when the temperature of the battery falls below a predetermined lower limit temperature that is lower than the upper limit temperature, the control unit estimates, from a travel route from the current location of the vehicle to the destination, at least a low-load travel route along which the vehicle travels with a low load on the battery, and a high-load travel route along which the vehicle travels with a high load that is greater than the low load, thereby calculating a load transition that represents a change in the load on the battery when the vehicle travels along the travel route; calculating a temperature transition of the battery based on the load transition and the current temperature of the battery; heating the battery before the load transitions to the high-load state when it is predicted that the temperature of the battery will be lower than the lower limit temperature when the load transitions from the low-load state to the high-load state; cooling the battery before the load enters the high-load state when it is predicted that the temperature of the battery will reach the upper limit temperature when the load is in the high-load state; a control system for an electric vehicle, which, when heating the battery, heats the battery so that the temperature reaches the lower limit temperature before the load transitions to the high-load state, and stops heating the battery when the temperature reaches the lower limit temperature before the load transitions to the high-load state.