JP5673452B2 - Battery pack temperature control device - Google Patents

Description

  The present invention relates to a temperature control device for an assembled battery in which a plurality of batteries are accommodated in a container.

  In general, the discharge characteristics of a battery vary with the temperature of the battery. For example, when the temperature of the battery is low, the capacity of the battery that can be discharged is reduced, and sufficient output characteristics cannot be obtained. Therefore, in the case of a vehicle that travels by rotating the motor with battery power, such as an electric vehicle such as an electric vehicle or a hybrid vehicle, the start performance or the like when traveling in a low temperature environment such as traveling in winter or traveling in a cold region, etc. Running performance may deteriorate and sufficient output may not be obtained.

On the other hand, it is known that when the temperature is high, the self-discharge of the battery increases and the remaining capacity of the battery tends to decrease. Therefore, when regenerative power generation is performed at the time of deceleration with the electric vehicle as described above, if the battery temperature rises excessively due to the environmental temperature or the heat generated by the battery itself, sufficient regenerative energy may not be obtained. Further, use at a high temperature tends to cause deterioration of the battery, leading to a reduction in battery life.
Under these circumstances, a temperature range (that is, an upper limit temperature and a lower limit temperature) suitable for use of the battery is usually determined. For electric vehicles equipped with a battery for traveling, various control methods for maintaining the battery temperature within a predetermined temperature range using on-vehicle cooling and heating devices have been proposed.

  For example, Patent Document 1 describes a technique for cooling a battery. In this technique, a plurality of battery cells are housed in a first case, a second case is provided outside the first case, and when the assembled battery is used, air is blown to the cells in the first case, and after the use of the assembled battery is finished The air is blown outside the first case in the second case for a predetermined time. Thereby, even if an assembled battery is arrange | positioned near a heat source, it is supposed that the temperature rise of a 1st case can be suppressed and the temperature of each cell in a 1st case can be kept uniform.

  In addition, Patent Document 2 describes a heat retention system for a secondary battery that is provided with an electric heater that heats the battery using regenerative energy generated when the electric vehicle is decelerated with respect to a technique for heating the inside of the battery case. ing. The electric heater is provided on the bottom surface of each secondary battery, and heats the secondary battery with regenerative power when the temperature of the secondary battery falls below a predetermined lower limit temperature. Thus, the battery can be kept warm with a simple configuration.

Japanese Patent No. 4081856 JP 2008-103108 A

  By the way, in order to cool or heat the inside of the container in which the battery is accommodated, a container provided with a supply port for supplying air into the container and an exhaust port for discharging air from the container as in Patent Document 1. Can be considered. The battery contained in such a container is cooled or heated by cold air or hot air supplied from the supply port, and adjusted so that the temperature of the battery is kept within a temperature range suitable for its use. Is done.

  At this time, for example, when cooling a battery module in which a plurality of battery cells are housed in a container as in Patent Document 1, battery cells arranged on the upstream side near the supply port are supplied from the supply port into the container. Because it receives the cold air directly, it is easy to cool and the temperature tends to decrease. However, since the battery cell arranged on the downstream side near the exhaust port is cooled by the air that has flowed around the upstream battery cell and increased in temperature, the temperature is unlikely to decrease. The same applies to heating (heating) the battery. The battery placed on the upstream side is easily heated by hot air, but the battery placed on the downstream side goes around the upstream battery. The temperature is difficult to rise because it is heated by the air that has been circulated and the temperature has dropped.

  Thus, when controlling the temperature of a plurality of batteries housed in a container, the temperature is likely to change (temperature rise or temperature drop) depending on the position of the battery placed in the container, and the temperature is not likely to change. If there is a temperature difference between these batteries, there is a risk that the temperature difference between the batteries will increase if cooling or heating is continued in this state. When the temperature difference between the batteries becomes large, there are problems such that the desired discharge characteristics cannot be obtained and the input / output performance is lowered, or the charging performance is lowered and the battery life is reduced. In the case of a battery mounted on an electric vehicle, if the temperature difference between the batteries becomes large, the desired starting performance and running performance cannot be obtained, leading to a deterioration in power consumption and a decrease in the life of the assembled battery. There is also a problem such as taking.

  In addition, for example, when the temperature of a plurality of batteries housed in a container is detected and the cooling and heating of the batteries can be switched according to the detected temperatures, the temperature difference between the batteries as described above. When this occurs, it becomes difficult to appropriately manage the temperature of the battery, and there is a problem that control hunting is likely to occur such that cooling and heating are frequently repeated. In addition, when cooling and heating in the battery container are frequently repeated, there is a problem that the heater is repeatedly turned on and off, and the inrush current to the heater is increased.

This case has been devised in view of such problems, and in an assembled battery in which a plurality of batteries are accommodated in a container, it is possible to eliminate the temperature difference between the batteries while suppressing hunting when switching between heating and cooling. An object of the present invention is to provide a temperature control device for an assembled battery, which is made possible.
The present invention is not limited to this purpose, and is a function and effect derived from each configuration shown in the embodiments for carrying out the invention described later, and other effects of the present invention are to obtain a function and effect that cannot be obtained by conventional techniques. Can be positioned.

(1) An assembled battery temperature control device disclosed herein includes a fan that guides air into a container that houses a plurality of batteries, and a heater that heats the air flowing into the container. A flow path for switching between a flow of air that discharges the air guided into the container to the outside and a flow of air that circulates the air guided into the container through the heater and into the container The assembled battery based on the highest temperature and the lowest temperature among the temperature of the plurality of batteries detected by the plurality of temperature sensors, a plurality of temperature sensors for detecting the temperature of the plurality of batteries, respectively. Temperature control means for adjusting the temperature of the fan, and fan control means for controlling the flow rate of air guided into the container by adjusting the strength of the fan, wherein the fan has stepwise strength. , Ru with a
The temperature control means has a temperature difference between the maximum temperature and the minimum temperature equal to or greater than a predetermined first switching temperature difference , the maximum temperature is equal to or higher than a predetermined required cooling temperature, and the minimum temperature is equal to a predetermined required heating temperature. The heater is stopped when the temperature is lower than the first switching temperature higher than the second temperature, or when the maximum temperature is equal to or higher than the second switching temperature lower than the cooling required temperature and the minimum temperature is lower than the heating required temperature. you implement temperature leveling control circulating air between the heater and the vessel by the flow path switching unit in a state in which operating the fan. Further, the temperature control means stops the operation of the heater and weakens the strength of the fan when the temperature difference is less than a second switching temperature difference that is higher than the first switching temperature difference. By means, weak temperature equalization control is performed in which air is circulated between the inside of the container and the heater.
The maximum temperature means the temperature of the hottest battery among the plurality of batteries. Similarly, the minimum temperature means the temperature of the lowest temperature battery. In other words, the highest temperature among the temperatures distributed in the container is the highest temperature, and the lowest temperature is the lowest temperature.

(2) When the temperature control means is in a state where both the heater and the fan are operated when the minimum temperature is lower than the heating required temperature, the flow path switching means causes a gap between the inside of the container and the heater. It is preferable to implement heating control that circulates air .
(3) It is preferable that the heater has stepwise strength, and includes heater control means for controlling the temperature of air flowing into the container by adjusting the strength of the heater. In this case, the temperature control means, said maximum case temperature is above lower third switching temperature than the previous SL second switching temperature and less than the second switching temperature, or the lowest temperature and is below the main heating temperature the When the temperature is equal to or higher than the fourth switching temperature that is lower than the heating required temperature, the fan is operated to weaken the strength of the heater, and the flow path switching means circulates air between the container and the heater. It is preferable to implement control.

(4) before SL temperature control means, the case where the maximum temperature is above lower third switching temperature than the less than the second switching temperature and the second switching temperature, or the lowest temperature and is below the main heating temperature the When the temperature is equal to or higher than the fourth switching temperature lower than the required heating temperature, the heater is operated to weaken the strength of the fan, and the air flow is circulated between the container and the heater by the flow path switching means. It is preferable to implement control.

(5) An assembled battery temperature control device disclosed herein includes a fan that guides air into a container that houses a plurality of batteries, and a heater that heats the air flowing into the container. A flow path for switching between a flow of air that discharges the air guided into the container to the outside and a flow of air that circulates the air guided into the container through the heater and into the container The assembled battery based on the highest temperature and the lowest temperature among the temperature of the plurality of batteries detected by the plurality of temperature sensors, a plurality of temperature sensors for detecting the temperature of the plurality of batteries, respectively. Temperature control means for adjusting the temperature of the heater, heater control means for controlling the temperature of the air flowing into the container by adjusting the strength of the heater, wherein the heater has stepwise strength, Is provided.
When the temperature difference between the maximum temperature and the minimum temperature is equal to or greater than a predetermined first switching temperature difference, the temperature control means stops the operation of the heater and operates the fan in a state where the fan is operated. Thus, temperature equalization control is performed to circulate air between the inside of the container and the heater. Further, the temperature control means is configured such that when the minimum temperature is lower than a predetermined heating temperature, the flow path switching means causes the heater and the fan to operate between the inside of the container and the heater. implement heating control circulating air. Further, the temperature control means is configured such that the maximum temperature is lower than a second switching temperature lower than a predetermined cooling temperature and not less than a third switching temperature lower than the second switching temperature, or the minimum temperature is the required temperature. When the temperature is lower than the heating temperature and higher than the fourth switching temperature lower than the required heating temperature, the fan is operated to weaken the strength of the heater, and the air flow is switched between the inside of the container and the heater by the flow path switching means. We implement weak heating control that circulates.

(6) the fan be one having a graded strength, Rukoto comprises a fan control means for controlling the flow rate of air that is introduced into the vessel by adjusting the strength of the fan is preferable. In this case, the temperature control means, the case where the maximum temperature is above the second switching temperature and less than before Symbol third switching temperature or the minimum temperature is less than said main heating temperature and before Symbol above fourth switching temperature In this case, it is preferable to perform weak heating control in which the heater is operated to weaken the strength of the fan so that air is circulated between the container and the heater by the flow path switching unit.

(7) An assembled battery temperature control device disclosed herein includes a fan that guides air into a container that houses a plurality of batteries, and a heater that heats the air flowing into the container. A flow path for switching between a flow of air that discharges the air guided into the container to the outside and a flow of air that circulates the air guided into the container through the heater and into the container The assembled battery based on the highest temperature and the lowest temperature among the temperature of the plurality of batteries detected by the plurality of temperature sensors, a plurality of temperature sensors for detecting the temperature of the plurality of batteries, respectively. Temperature control means for adjusting the temperature of the fan, and fan control means for controlling the flow rate of air guided into the container by adjusting the strength of the fan , wherein the fan has stepwise strength. , Ru with a
When the temperature difference between the maximum temperature and the minimum temperature is equal to or greater than a predetermined first switching temperature difference, the temperature control means stops the operation of the heater and operates the fan in a state where the fan is operated. Thus, temperature equalization control is performed to circulate air between the inside of the container and the heater. Further, the temperature control means is configured such that when the minimum temperature is lower than a predetermined heating temperature, the flow path switching means causes the heater and the fan to operate between the inside of the container and the heater. Implement heating control to circulate air. Further , the temperature control means is configured such that the maximum temperature is lower than a second switching temperature lower than a predetermined cooling temperature and not less than a third switching temperature lower than the second switching temperature, or the minimum temperature is the required temperature. When the temperature is lower than the heating temperature and higher than the fourth switching temperature lower than the required heating temperature, the heater is operated to reduce the strength of the fan, and the air is switched between the inside of the container and the heater by the flow path switching means. you implement the weak heating control for circulating.

(8) the temperature control means, when said maximum temperature is the main cooling temperature and less than the minimum temperature the temperature difference is less than the said first switching temperature difference is more than the main heating temperature, the fan and the It is preferable to perform holding control for stopping the operation of the heaters and holding the flow path switching means in the current state.

According to the battery pack temperature control apparatus of the present invention, in the battery pack having a plurality of batteries, the maximum temperature and the minimum temperature among the temperatures detected by the plurality of temperature sensors are acquired, and the maximum temperature and the minimum temperature are obtained. Temperature equalization control is performed when the temperature difference is greater than or equal to a predetermined first switching temperature difference. In this temperature equalization control, the flow path switching means and the fan are controlled so that air circulates between the inside of the container and the heater in a state where the operation of the heater is stopped. The temperature difference between the plurality of batteries can be eliminated without adding or removing heat from the battery (that is, without heating or cooling).
That is, when the temperature difference between the plurality of batteries is equal to or greater than the first switching temperature difference, the temperature equalization control is performed instead of the cooling control or heating control, so that the cooling control and the heating control are not repeated. (In other words, the occurrence of hunting is suppressed), and the temperature difference can be reliably eliminated.

It is a block diagram which shows the structure of the temperature control apparatus of the assembled battery which concerns on one Embodiment. It is a block diagram of the vehicle provided with the temperature control apparatus of the assembled battery which concerns on one Embodiment. It is a graph explaining the relationship between the temperature of a battery, and the control content, (a) shows the control aspect implemented in the temperature control apparatus of the assembled battery which concerns on one Embodiment, (b) is in the conventional temperature control apparatus The control aspect currently implemented is shown. It is a flowchart which shows the control content by the temperature control apparatus of the assembled battery which concerns on one Embodiment.

Hereinafter, embodiments will be described with reference to the drawings. Note that the embodiment described below is merely an example, and there is no intention to exclude various modifications and technical applications that are not explicitly described in the following embodiment.
[1. Device configuration]
The structure of the temperature control apparatus of the assembled battery which concerns on one Embodiment is demonstrated using FIGS. 1-3. This temperature control device is suitable for use in an electric vehicle such as an electric vehicle or a hybrid vehicle. Here, a description will be given of an example applied to a hybrid vehicle.

[1-1. overall structure]
FIG. 2 is a configuration diagram of a vehicle provided with the temperature control device. As shown in FIG. 2, a vehicle 1 is connected to an output shaft (rotary shaft) 2 a of an engine (ENG) 2 with a rotary shaft 4 a of a motor generator (hereinafter also referred to as “motor”) 4 via a clutch 3. 4 is configured as a parallel hybrid vehicle in which an input shaft 5a of a transmission (T / M) 5 is directly connected to a rotating shaft 4a. The output shaft 5b of the transmission 5 is connected to the left and right drive wheels 7 via a propeller shaft 6, a differential (not shown) and a drive shaft. Therefore, when the clutch 3 is connected, both the output shaft 2a of the engine 2 and the rotating shaft 4a of the electric motor 4 are mechanically connected to the drive wheels 7, and when the clutch 3 is disconnected, the electric motor 4 rotates. Only the shaft 4 a is mechanically connected to the drive wheel 7.

  The electric motor 4 operates as an electric motor (motor) when the DC power stored in the battery (assembled battery) 10 is converted into AC power by the inverter 8 and supplied, and the driving force thereof is adjusted to an appropriate speed by the transmission 5. After being converted to, it is transmitted to the drive wheel 7. Further, when the vehicle is decelerated, the electric motor 4 operates as a generator, and the kinetic energy generated by the rotation of the drive wheels 7 is transmitted to the electric motor 4 through the transmission 5 and converted into AC power, thereby generating a regenerative braking force. . The AC power is converted into DC power by the inverter 8 and then charged to the battery 10, and the kinetic energy due to the rotation of the drive wheels 7 is recovered as electric energy.

  On the other hand, the driving force of the engine 2 is transmitted to the transmission 5 via the rotating shaft 4a of the electric motor 4 when the clutch 3 is connected, and is transmitted to the drive wheels 7 after being shifted to an appropriate speed. . Therefore, when the electric motor 4 operates as a motor when the driving force of the engine 2 is transmitted to the driving wheels 7, the driving force of the engine 2 and the driving force of the electric motor 4 are transmitted to the driving wheels 7, respectively. . That is, a part of the driving torque to be transmitted to the driving wheel 7 for driving the vehicle 1 is supplied from the engine 2 and the rest is supplied from the electric motor 4.

  When the charging rate of the battery 10 decreases and the battery 10 needs to be charged, the electric motor 4 operates as a generator, and the electric motor 4 is driven using a part of the driving force of the engine 2. As a result, power generation is performed, and the generated AC power is converted into DC power by the inverter 8 and then the battery 10 is charged. A heater 11 for heating the inside of the battery 10 is provided in the vicinity of the battery 10.

In addition, the vehicle 1 is provided with an air conditioner (A / C) 9 for adjusting the temperature of air in the passenger compartment, in addition to the drive system and the power generation system. Further, the vehicle 1 is provided with an electronic control device (hereinafter referred to as ECU) for controlling these devices. That is, the vehicle 1 includes an engine ECU (ENG_ECU) 12 that controls the engine 2, an inverter ECU 13 that controls the inverter 8, an air conditioner ECU (A / C_ECU) 14 that controls the air conditioner 9, the management of the battery 10, and the control of the heater 11. Vehicle ECU15 which performs etc. is each provided. The vehicle ECU 15 also performs integrated control of the vehicle 1 through the engine ECU 12, the inverter ECU 13, and the air conditioner ECU 14. Each ECU12-15 is a computer comprised by memory (ROM, RAM), CPU, etc.
In addition, about each function of engine ECU12, inverter ECU13, and air-conditioner ECU14, since a well-known technique is applicable, it abbreviate | omits for details.

[1-2. Configuration of temperature controller]
FIG. 1 is a block diagram showing the configuration of the present temperature control apparatus. As shown in FIG. 1, a battery 10, a heater 11, a vehicle ECU 15, and a pipe 20 are provided in the passenger compartment 1 a, and the air conditioner ECU 14, the pipes 17 and 18, and the pipe 17 are provided outside the passenger compartment 1 a. The air conditioner blower 9a and the air conditioner side shutter valve 9b are provided. The piping 17 serves as a passage for introducing outside air into the passenger compartment 1a, and the piping 18 serves as a passage for circulating air in the passenger compartment 1a to the piping 17. The air conditioner-side shutter valve 9b is a switching valve that is provided at a connection portion between the pipes 17 and 18, and is controlled by the air conditioner ECU 14 to switch the air flow. A compressor, a condenser, etc. (not shown) are provided on the upstream side of the air conditioner blower 9a and the air conditioner side shutter valve 9b, and the air conditioner 9 (see FIG. 2) is configured by these. The interior of the passenger compartment 1a is air-conditioned by the air conditioner 9.

  The battery 10 is configured as an assembled battery in which a plurality of battery modules (batteries) 31 are accommodated in a battery case (container) 30. Here, four battery modules 30 are accommodated in the battery case 30, four in the longitudinal direction and two in the lateral direction. Each battery module 31 is, for example, an assembled battery in which a plurality of battery cells are connected in series in a case. The number of battery modules is not limited to this. In addition, the battery case 30 is assumed to be fixed at an arbitrary position in the passenger compartment 1a (for example, in the trunk room of the vehicle 1 or the inside of the instrument panel).

  The plurality of battery modules 31 are accommodated in the battery case 30 with a gap therebetween. The plurality of battery modules 31 are cooled or heated as air supplied from a supply flow path 21 or a circulation flow path 23 described later flows around each battery module 31. Thereby, the temperature adjustment of the battery 10 is performed. Each battery module 31 is provided with a temperature sensor 32, and the temperature of each battery module 31 is detected by each temperature sensor 32. The detected temperature information of each battery module 31 is transmitted to the vehicle ECU 15. In FIG. 1, the gaps between the battery modules 31 are greatly expressed for easy understanding. Further, although only two temperature sensors 32 are shown, one temperature sensor 32 is provided in one battery module 31.

  The heater 11 is a heater such as a PTC heater, for example, and heats air flowing through the heater 11 when the switch is on. The heating capacity of the heater 11 can be changed in stages. Here, the strength is switched between two levels of high / low (strong / weak). That is, when the strength of the heater 11 is high (strong), the air can be heated more than when the strength is low (in other words, the air can be heated to a higher temperature). . On / off control (operation control) and temperature switching control (strength control) of the switch of the heater 11 are performed by a heater control unit 15c described later provided in the vehicle ECU 15. Note that the temperature switching when the switch is on may be more than two stages. The heater 11 is used when heating the inside of the battery case 30 as will be described later. Hereinafter, heating the space in the battery case 30 is also simply expressed as “heating the battery 10”, “heating the battery module 31”, or the like.

The piping 20 includes a supply flow path 21 for supplying the air in the vehicle compartment 1a into the battery case 30, and a discharge flow path 22 for discharging the air that has circulated through the battery case 30 to the outside of the vehicle compartment 1a. And a circulation flow path 23 for circulating the air discharged from the discharge flow path 22 back to the battery case 30 again.
The supply channel 21 is provided with an upstream end opened at an arbitrary position in the passenger compartment 1a, and a downstream end at one end in the longitudinal direction of the battery case 30 (here, one end in the longitudinal direction of the battery case 30). Corner).

  The upstream end of the discharge channel 22 is at the other end in the longitudinal direction of the battery case 30 (here, the corner at the other end in the longitudinal direction of the battery case 30 and facing the supply channel 21). The downstream end is connected and opened toward the outside of the passenger compartment 1a. On the upstream side of the discharge flow path 22, air is introduced from the supply flow path 21 or the circulation flow path 23 into the battery case 30 and discharged from the discharge flow path 22 (that is, an air flow is formed in the battery case 30. Fan 25 is provided.

  The fan 25 has stepwise strength (air blowing capability), and here, the strength is switched between two levels of high / low (strong / weak). That is, when the strength of the fan 25 is high, more air can be guided into the battery case 30 than when the strength is low (in other words, the flow rate of air can be increased). ). On / off control (operation control) and flow rate switching control (strength control) of the switch of the fan 25 are controlled by a fan control unit 15b described later provided in the vehicle ECU 15. Further, a gap 22 c is provided on the downstream side of the discharge flow path 22. Due to the gap 22c, the air flowing through the discharge flow path 22 is slightly discharged into the passenger compartment 1a, and a negative pressure is hardly generated in the passenger compartment 1a.

  The circulation channel 23 has an upstream end connected to an intermediate portion of the discharge channel 22, and a downstream end one end portion in the longitudinal direction of the battery case 30 (here, a short direction with respect to the connection portion of the supply channel 21). This is a flow path that is connected to the other end side and allows air flowing through the discharge flow path 22 to flow into the battery case 30 again. A heater 11 is interposed in the circulation channel 23, and the heater 11 heats the air flowing through the circulation channel 23. That is, the circulation channel 23 circulates air between the heater 11 and the battery case 30.

  A shutter valve (flow path switching means) 24 that switches the flow state of air in the battery case 30 is provided at a connection point between the discharge flow path 22 and the circulation flow path 23. When the shutter valve 24 is closed, the upstream side and the downstream side of the discharge flow path 22 are in communication with each other, and when the shutter valve 24 is open, the upstream side of the discharge flow path 22 and the circulation flow path 23 are in communication. . In other words, when the shutter valve 24 is closed, air is introduced into the battery case 30 from the supply flow path 21 and discharged from the discharge flow path 22 to the outside of the vehicle compartment 1a. In addition, when the shutter valve 24 is open, air is introduced into the battery case 30 from the circulation flow path 23, passes through the heater 11 in the circulation flow path 23 from the discharge flow path 22, and flows into the battery case 30 again. To do.

  That is, after the shutter valve 24 heats the air guided into the battery case 30 to the outside from the discharge flow path 22 and the air guided into the battery case 30 with the heater 11 ( The air flow to be circulated into the battery case 30 (after passing through the heater 11) is switched. In other words, the shutter valve 24 switches between the flow of air that does not pass through the heater 11 and the flow of air that passes through the heater 11. The switching control of the shutter valve 24 is performed by a shutter control unit 15d described later provided in the vehicle ECU 15.

[2. Control configuration]
[2-1. Overview of control]
In the vehicle ECU 15 of the present embodiment, mainly four controls are performed. The first control is a cooling control that cools the battery, the second control is a heating control that warms (warms) the battery, the third control is a temperature equalization control that equalizes the temperature of the battery, and the fourth control is This is holding control for holding the temperature of the battery.
The cooling control is a control for cooling the battery 10 as a whole by cooling the battery module 31 in the battery case 30 by introducing cold air (cold air) into the battery case 30.

  The heating control is control for heating the battery 10 as a whole by heating the battery module 31 in the battery case 30 by flowing heated air (hot air) into the battery case 30. The heating control includes a first heating control in which the strength of both the heater 11 and the fan 25 is in a high state, and a second heating control in which at least one strength of the heater 11 and the fan 25 is in a low state (weak). Heating control). In the second heating control described in the present embodiment, the strengths of the heater 11 and the fan 25 are both in a low state. Hereinafter, when the first heating control and the second heating control are not particularly distinguished, they are simply referred to as heating control.

  In the temperature equalization control, the temperature of a plurality of battery modules 31 in the battery case 30 is made uniform by circulating air between the battery case 30 and the heater 11 with the heater 11 switched off. It is control to make it. That is, the temperature of the battery module 31 is leveled without causing cold air or hot air to flow into the battery case 30. In this temperature equalization control, the first temperature equalization control when the strength of the fan 25 is high, the second temperature equalization control (weak temperature equalization control) when the strength of the fan 25 is low, and Is included. Hereinafter, when the first temperature uniformization control and the second temperature uniformization control are not particularly distinguished, they are simply referred to as temperature uniformization control.

The holding control is control for holding the temperature of the battery module 31 in the battery case 30 in the current state without allowing air to flow into the battery case 30.
In the vehicle ECU 15 of the present embodiment, any one of cooling control, heating control, temperature equalization control, and holding control is controlled based on the highest highest temperature and the lowest lowest temperature among the temperatures of the plurality of battery modules 31. Is implemented.

[2-2. Control block configuration]
In order to realize the above four controls, the vehicle ECU 15 functions as a battery management unit 15a, a function component as a fan control unit 15b, a function component as a heater control unit 15c, and a shutter control unit 15d. And a functional element as the temperature control unit 15e.

The battery management unit (battery management unit, BMU) 15a detects the temperature and voltage of the battery 10, the current flowing between the inverter 8 and the battery 10, and calculates the charging rate of the battery 10 from these detection results. The state of the battery 10 is monitored so as not to be overcharged or overdischarged. Here, the battery management unit 15a collects the temperatures of all the battery modules 31 detected by the temperature sensor 32, and from these temperature information, among the temperatures of all the battery modules 31, the battery module 31 having the highest temperature is collected. The temperature (hereinafter referred to as the maximum temperature) T _MAX and the temperature (hereinafter referred to as the minimum temperature) T _{MIN of the} lowest temperature battery module 31 are selected and acquired. The information acquired by the battery management unit 15a is transmitted to the temperature control unit 15e.

  The fan control unit (fan control means) 15b controls on / off of the switch of the fan 25 (operation of the fan 25) and the strength of the fan 25 when the switch is on in accordance with a command from the temperature control unit 15e. Is. Here, since the fan 25 is switched to two levels of strength, the fan control unit 15b controls the flow rate of the air guided into the battery case 30 by switching the strength of the fan 25.

  The heater control unit (heater control means) 15c controls on / off of the switch of the heater 11 (operation of the heater 11) and the strength of the heater 11 when the switch is on in accordance with a command of the temperature control unit 15e. Is. Here, since the heater 11 can be switched to two levels of strength, the heater control unit 15 c controls the temperature of the air flowing through the heater 11 and flowing into the battery case 30 by switching the strength of the heater 11. To do.

  The shutter control unit (flow path switching unit) 15d controls opening and closing of the shutter valve 24 in accordance with a command from the temperature control unit 15e. That is, the shutter control unit 15d performs the closing / closing control of the shutter valve 24, thereby causing the air to be introduced into the battery case 30 from the supply passage 21 and the air from the circulation passage 23 into the battery case 30. The flow path to be guided is switched.

The temperature control unit (temperature control means) 15e is configured to adjust the temperature of the battery 10 to an appropriate temperature based on the maximum temperature _TMAX and the minimum temperature _TMIN transmitted from the battery management unit 15a. One control is implemented. Hereinafter, description will be made one by one with reference to a graph showing the relationship between the maximum temperature T _MAX and the minimum temperature T _MIN and the control contents shown in FIG. In FIG. 3A, on the diagonal line extending from the lower left corner to the upper right corner of the graph, the maximum temperature T _MAX and the minimum temperature T _MIN indicate the same temperature, and the maximum temperature T _MAX and the minimum temperature T are on this line. The temperature difference from _MIN is zero, and the lower right region from this diagonal is a region that does not exist. Further, FIG. 3B shows the contents of the conventional temperature control for comparison, and values and regions with the same reference numerals as those in FIG. 3A correspond to those in FIG. .

First, the cooling control will be described. Temperature control unit 15e, the temperature at which the maximum temperature T _MAX requires cooling (hereinafter, this temperature is needed that the cooling temperature) when the above T _C, the temperature of the lowest temperature T _MIN requires heating (hereinafter, this If the temperature is equal to or higher than the first switching temperature T ₁ set to a temperature higher than T _{H (referred} to as “heating required temperature”), it is determined that the battery 10 needs to be cooled, and the cooling control is performed. This corresponds to the area A in FIG. That is, the cooling control implementation condition is the following (1).
(1) T _MAX ≧ T _C and T _MIN ≧ T ₁

Incidentally, the main cooling temperature T _C is a threshold for determining whether or not to cool the battery 10, a main heating temperature T _H is a threshold for determining whether to perform the heating of the battery 10 . The required cooling temperature T _C and the required heating temperature _TH are set in advance according to the battery module 31 used. For example, the required cooling temperature T _C = 30 ° C. and the required heating temperature T _H = 10 ° C. Is set. Note that these values are examples.

  When the above condition (1) is satisfied (when cooling control needs to be performed), the temperature control unit 15e switches on the fan 25 with respect to the fan control unit 15b to increase its strength. The command is issued. Further, the heater controller 15c is instructed to turn off the heater 11 to stop the operation. Further, it instructs the shutter control unit 15d to close the shutter valve 24. In response to these instructions, the temperature control unit 15 e supplies the cooled air in the passenger compartment 1 a to the battery module 31 in the battery case 30 to cool the battery 10.

Next, heating control will be described. Temperature control unit 15e, when the minimum temperature T _MIN is less than the main heating temperature T _H, if the maximum temperature T _MAX is the second switching temperature T ₂ less than a set at a temperature lower than the main cooling temperature T _C, Heating control is performed by determining that heating of the battery 10 is necessary. This corresponds to the regions B and C in FIG. That is, the heating control implementation condition is the following (2).
(2) T _MAX <T ₂ and T _MIN <T _H

  When the above condition (2) is established (when it is necessary to perform heating control), the temperature control unit 15e issues a command to turn on the switch of the fan 25 to the fan control unit 15b. Commands the heater controller 15c to turn on the heater 11 switch. In addition, it instructs the shutter control unit 15d to open the shutter valve 24. In response to these instructions, the temperature control unit 15 e supplies the air heated by the heater 11 to the battery module 31 in the battery case 30 to heat the battery 10.

  At this time, the temperature control unit 15e repeatedly passes the air released from the battery case 30 through the heater 11 to heat it, and repeatedly supplies the heated air into the battery case 30. In other words, air heated from the heater 11 is circulated between the battery case 30 and the heater 11 by circulating air from the discharge channel 22 to the circulation channel 23. Thereby, the battery 10 is efficiently heated.

  Note that the heating control includes the first heating control and the second heating control as described above. Among these, 1st heating control is control implemented when it is necessary to heat the battery module 31 more strongly, and is implemented when the temperature of the battery 10 is low entirely. On the other hand, the second heating control is control performed when the battery module 31 is heated more slowly than the first heating control. Although the temperature of the battery 10 is generally low, the first heating control is performed. This is performed at a higher temperature than when the control is performed.

Temperature control unit 15e, the maximum temperature T _MAX is at a third lower than the switching temperature T ₃ set in the second switching temperature T ₂ temperature lower than the minimum temperature T _MIN is lower temperature than the main heating temperature T _H if the fourth lower than the switching temperature T ₄ which is set to be out the first heating control and determines that it is necessary to enhance the heating of the battery 10. This corresponds to the region B in FIG. That is, the implementation condition of the first heating control is (3) below.
(3) T _MAX <T ₃ and T _MIN <T ₄

The temperature control unit 15e, when a the highest temperature T _MAX is the second switching temperature T ₂ and less than the third switching temperature T ₃ than the lowest temperature T _MIN below main heating temperature T _H, or the minimum temperature T If _MIN is the highest temperature T _MAX a and the fourth switching temperature T ₄ or more but less than main heating temperature T _H is lower than the third switching temperature T _3, the second heating is determined that heating of the battery 10 is required Implement control. This corresponds to the area C in FIG. That is, the implementation condition of the second heating control is the following (4) or (5).
(4) T ₃ ≦ T _MAX <T ₂ and T _MIN <T _H
(5) T _MAX <T ₃ and T ₄ ≦ T _MIN <T _H
Note that the above-described heating control execution condition (2) is obtained by combining the first heating control execution condition (3) and the second heating control execution condition (4) and (5).

  When the execution condition (3) of the first heating control is satisfied, the temperature control unit 15e sets the strength of the heater 11 and the fan 25 to high with respect to the fan control unit 15b and the heater control unit 15c. A command is issued so that the first heating control is performed. On the other hand, when the execution condition (4) or (5) of the second heating control is satisfied, the temperature control unit 15e is stronger than the fan control unit 15b and the heater control unit 15c. A command is issued so that both are low, and the second heating control is performed.

Next, temperature equalization control will be described. The temperature control unit 15e calculates a temperature difference ΔT between the maximum temperature T _MAX and the minimum temperature T _MIN, and if this temperature difference ΔT is equal to or greater than a predetermined first switching temperature difference ΔT ₁ , the temperature of the plurality of battery modules 31 is calculated. Temperature equalization control is performed to make the temperature uniform. This temperature equalization control does not add or actively remove heat from the outside, but guides and mixes air into the battery case 30 to equalize the amount of heat each of the battery modules 31 has. is there.

  For this reason, when the temperature control unit 15e performs temperature equalization control, the temperature control unit 15e issues a command to turn on the switch to the fan control unit 15b, and turns off the switch of the heater 11 to the heater control unit 15c. The command is issued. Further, the shutter control unit 15d is instructed to open the shutter valve 24, and air is circulated between the battery case 30 and the heater 11 (in other words, external air is not taken in from the supply flow path 21). ).

The implementation conditions of temperature equalization control are the following (6).
(6) ΔT ≧ ΔT ₁ Note that ΔT = T _MAX −T _MIN
However, even if this condition (6) is satisfied, if the above-described cooling condition (1) or heating condition (2) is satisfied, the temperature control unit 15e gives priority to cooling control and heating control. carry out. In other words, the temperature equalization control is performed when the temperature difference ΔT between the maximum temperature T _MAX and the minimum temperature T _MIN is equal to or greater than the first switching temperature difference ΔT ₁ and cooling control and heating control are not required. It is. This corresponds to the regions D and E in FIG. That is, the implementation condition of temperature equalization control is the following (7) with the above condition (6) added.
(7) ΔT ≧ ΔT ₁ and T _MAX <T _C and T _MIN ≧ T _H

Also, if that do not meet the above criteria (7) (i.e., when T _MAX ≧ T _C and T _MIN <T _H) when even, satisfying the following condition (8) or (9), Temperature equalization control is performed. In other words, the condition (8) to which the condition (6) is added or the condition (9) to which the condition (6) is added is also an implementation condition for temperature equalization control.
(8) ΔT ≧ ΔT ₁ , T _MAX ≧ T _C and T _MIN <T ₁
(9) ΔT ≧ ΔT ₁ , T _MAX ≧ T ₂ and T _MIN <T _H

Note that the temperature equalization control includes the first temperature equalization control and the second temperature equalization control as described above. Among these, the first temperature equalization control is control performed when the temperature difference ΔT between the maximum temperature T _MAX and the minimum temperature T _MIN of the battery module 31 is made uniform more quickly, and the temperature difference ΔT It is implemented when is large. On the other hand, the second temperature equalization control is a control performed when the temperature difference ΔT is eliminated more slowly than the first temperature equalization control, and is performed when the temperature difference ΔT is small. The

When the temperature difference ΔT between the maximum temperature T _MAX and the minimum temperature T _MIN is equal to or greater than the second switching temperature difference ΔT ₂ set to a temperature difference larger than the first switching temperature difference ΔT ₁ , the temperature control unit 15e It is determined that the temperature difference between the battery modules 31 needs to be eliminated more quickly, and the first temperature equalization control is performed. This corresponds to the area D in FIG. That is, the implementation condition of the first temperature equalization control is the following condition (10) in addition to any of the above conditions (7) to (9).
(10) ΔT ≧ ΔT ₂

Further, the temperature control unit 15e performs the second temperature equalization control when the temperature difference ΔT is not less than the first switching temperature difference ΔT ₁ and less than the second switching temperature difference ΔT ₂ . This corresponds to the region E in FIG. That is, the implementation condition of the second temperature equalization control is the following condition (11) in addition to any of the above conditions (7) to (9).
(11) ΔT ₁ ≦ ΔT <ΔT ₂

  When performing temperature equalization control, the temperature control unit 15e causes the fan control unit 15b to switch to the fan control unit 15b when the above condition (10) is satisfied in addition to any of the above conditions (7) to (9). On the other hand, a command is issued so that the strength of the fan 25 is high, and the first temperature equalization control is performed. On the other hand, the temperature control unit 15e increases the strength of the fan 25 with respect to the fan control unit 15b when the above condition (11) is satisfied in addition to any of the above conditions (7) to (9). A command is issued so as to be low, and the second temperature equalization control is performed.

Finally, holding control will be described. In the temperature control unit 15e, the temperature difference ΔT between the maximum temperature T _MAX and the minimum temperature T _MIN is less than the first switching temperature difference ΔT ₁ , the maximum temperature T _MAX is less than the required cooling temperature T _C, and the minimum temperature T _MIN is when the above main heating temperature T _H, the heating of the battery 10 nor to implement the holding control is judged to be unnecessary cooling. That is, the holding control is performed under the following condition (12).
(12) ΔT <ΔT ₁ and T _MAX <T _C and T _MIN ≧ T _H

  When the above condition (12) is satisfied, the temperature control unit 15e instructs the fan control unit 15b and the heater control unit 15c to turn off the fan 25 and the heater 11, respectively. Then, the shutter control unit 15d is instructed to hold the shutter valve 24 in the immediately previous state (that is, to maintain the current state). With these commands, the temperature control unit 15 e stops guiding air to the battery module 31 in the battery case 30 and maintains the current state of the battery 10.

  The contents of control by the temperature control unit 15e are summarized as shown in Table 1 below. In addition, the area | region in Table 1 respond | corresponds with the area | region in the graph of Fig.3 (a).

Note that the first switching temperature T ₁ , the second switching temperature T ₂ , the third switching temperature T _3, and the fourth switching temperature T ₄ as determination threshold values used when determining which control is to be performed are: If the type (property) and battery output of the battery 10, the type and request of the vehicle 1 (for example, the weight of the vehicle 1, the performance of the electric motor 4, etc.) change, it will change. For this reason, for example, in the map as shown in FIG. 3A, these determination threshold values are parameterized so that they can be appropriately set according to the output of the battery 10 or the request of the vehicle 1 as described above. Good. Further, it may be set in advance according to the type of the battery 10 or the type of the vehicle 1.
The first switching temperature difference [Delta] T ₁ and the second switching temperature difference [Delta] T ₂ as determination threshold value is preset to a value smaller than the difference between the main cooling temperature T _C and main heating temperature T _H. For example, the first switching temperature difference ΔT ₁ = 5 ° C. and the second switching temperature difference ΔT ₂ = 10 ° C. are set. Note that these values are examples.

[3. Action]
Since the temperature adjustment device according to the present embodiment is configured as described above, the temperature adjustment of the battery 10 is performed, for example, as follows.
When the ignition switch of the vehicle 1 is turned on, the temperature sensor 32 detects the temperature of each battery module 31, and this temperature information is transmitted to the vehicle ECU 15. The battery management unit 15a of the vehicle ECU 15 selects and acquires the highest temperature _TMAX and the lowest temperature _TMIN from this temperature information. The battery management unit 15a transmits the acquired maximum temperature _TMAX and minimum temperature _TMIN to the temperature control unit 15e. The temperature control unit 15e of the vehicle ECU 15 determines whether the cooling control of the battery 10, the heating control, the temperature equalization control, or the holding control is necessary based on the temperature information. To implement.

For example, when the battery 10 is at a low temperature when the vehicle 1 is started (when the maximum temperature T _MAX of the plurality of battery modules 31 is less than the third switching temperature T ₃ and the minimum temperature T _MIN is less than the fourth switching temperature T ₄ ). The temperature control unit 15e first performs the first heating control. As a result, the air heated by the heater 11 flows from the circulation flow path 23 into the battery case 30, and the battery module 31 disposed near the connection portion of the circulation flow path 23 (that is, upstream of the air flow). Gradually increases in temperature. On the other hand, the battery module 31 disposed near the connection portion of the discharge flow path 22 (that is, downstream of the air flow) flows around the battery module 31 on the upstream side and the temperature is lowered. Because it flows, it is hard to rise in temperature.

In other words, the temperature of the battery module 31 arranged on the upstream side is likely to rise, so that the temperature is highest (becomes the maximum temperature T _MAX ), and the temperature of the battery module 31 arranged on the downstream side is difficult to rise, so that the temperature is the highest. Lower (becomes minimum temperature T _MIN ). For this reason, if the first heating control is continued, the maximum temperature T _MAX increases further, while the minimum temperature T _MIN does not increase easily, and between the battery modules 31 arranged on the upstream side and the downstream side. A temperature difference occurs. This temperature difference increases while the first heating control is being performed. This phenomenon is represented by an upper right arrow in the region B in FIG.

The arrows shown in FIGS. 3A and 3B indicate a change tendency between the maximum temperature T _MAX and the minimum temperature T _MIN of the plurality of battery modules 31 when the corresponding temperature adjustment control is performed in each region. It is what. In other words, the inclination (gradient) in the direction indicated by the arrow increases between the maximum temperature T _MAX and the minimum temperature T _MIN as the temperature difference between the maximum temperature T _MAX and the minimum temperature T _MIN increases with respect to the diagonal line indicating zero. This means that the temperature difference ΔT increases.

For example, the upper right arrow in the region B indicates that the change rate (increase rate) of the maximum temperature T _MAX is larger than the change rate (increase rate) of the minimum temperature T _MIN , and the temperature difference ΔT increases. Show. Moreover, in the area C where the second heating control is performed, the slope of the upper right arrow is smaller than the arrow of the area B where the first heating control is performed. This is because the second heating control is gentler heating control than the first heating control, so the rate of change (increase rate) of the maximum temperature T _MAX is smaller than that of the region B, and the rate of change of the minimum temperature T _MIN ( This is because the change in the temperature difference ΔT (the expansion rate of the temperature difference ΔT, that is, the inclination in the direction indicated by the arrow) is small because the increase rate is slightly smaller than the region B or hardly changes.

The temperature state in the battery case 30 is expressed as a point (state point) on the graph of FIG. 3A having coordinates defined by the value of the maximum temperature T _{MAX and} the value of the minimum temperature T _MIN . be able to. As the temperature adjustment control proceeds, the state point moves in the direction of the arrow in the region where the point exists. The moving speed of the state point is a speed corresponding to the length of the arrow.

When the first heating control is performed when the battery 10 is at a low temperature when the vehicle 1 is started, the temperature of the battery module 31 gradually increases, and at least the maximum temperature T _MAX becomes equal to or higher than the third switching temperature T ₃ . When the minimum temperature T _MIN becomes the fourth switching temperature T ₄ or more, the temperature control unit 15e carries out a second heating control by switching the intensity of the heater 11 and the fan 25 is low. The temperature control unit 15e obtains information on the maximum temperature T _MAX and the minimum temperature T _MIN from the battery management unit 15a as needed, and based on these temperature information, the execution conditions (7) to (9 ) Or the holding control execution condition (12) is determined, and the second heating control is performed until the holding condition is satisfied. Implement the control.

Further, for example, when the battery 10 becomes hot while the vehicle 1 is traveling (when the maximum temperature T _MAX of the plurality of battery modules 31 is equal to or higher than the required cooling temperature T _C and the minimum temperature T _MIN is equal to or higher than the first switching temperature T _1. ), The temperature control unit 15e performs cooling control. As a result, external air (that is, air that does not pass through the heater 11) is guided into the battery case 30 from the supply flow path 21, and near the connection portion of the supply flow path 21 (that is, upstream of the air flow). The temperature of the battery module 31 disposed in the battery gradually decreases. On the other hand, the battery module 31 disposed near the connection portion of the discharge flow path 22 (that is, downstream of the air flow) flows around the upstream battery module 31 and has an increased temperature. Because it flows, it is hard to lower the temperature.

In other words, the temperature of the battery module 31 arranged on the upstream side is likely to decrease, and thus the temperature is the lowest (below the minimum temperature T _MIN ). (Maximum temperature T _MAX ). For this reason, if the cooling control is continued, the minimum temperature T _{MIN further} decreases, whereas the maximum temperature T _MAX does not decrease easily. In the cooling control, the battery modules 31 arranged on the upstream side and the downstream side are also not provided. There is a temperature difference between the two. This temperature difference increases while the cooling control is performed. This phenomenon is represented by a left downward arrow in the region A in FIG.

That is, when the cooling control is performed when the battery 10 becomes high temperature, the battery module 31 gradually decreases in temperature, and the minimum temperature T _MIN is less than the first switching temperature T ₁ or the maximum temperature T _MAX is required. When the temperature becomes lower than the cooling temperature T _C , the temperature control unit 15e performs the above-described temperature equalization control implementation conditions (7) to (9) and the holding control based on the information on the maximum temperature T _MAX and the minimum temperature T _MIN . It is determined whether or not the execution condition (12) is satisfied, and the cooling control is performed until it is satisfied. When the execution condition (12) is satisfied (that is, when the regions D, E, and F are satisfied), the control corresponding to the region is performed.

Moreover, the temperature control part 15e implements temperature equalization control, when any of implementation conditions (7)-(9) of above-described temperature equalization control is satisfied. In the temperature equalization control, only the fan 25 is operated at a high or low strength, and air that is not heated by the heater 11 flows into the battery case 30 from the circulation flow path 23. The amount of heat moves from the battery module 31 having a high temperature to the battery module 31 having a low temperature (that is, heat is transferred).
In other words, when temperature equalization control is performed, the maximum temperature T _MAX decreases and the minimum temperature T _MIN increases due to heat conduction (convection) due to the flow of air, so the temperature difference ΔT decreases. This phenomenon is represented by the downward-pointing arrows in the regions D and E in FIG. Here, it is assumed that there is no heat loss when the amount of heat moves from the high temperature battery module 31 to the low temperature battery module 31 (that is, the sum of the temperatures is considered constant), and the slope of the arrow is It is perpendicular to the diagonal.

Further, the temperature control unit 15e performs the holding control when the holding control execution condition (12) is satisfied. In the holding control, air is not guided into the battery case 30 in order to stop the operation of the fan 25. Therefore, the temperature difference ΔT is not actively changed in the holding control region F. The region F is a region most suitable as a temperature at which the battery 10 is used. In other words, the temperature control unit 15 e performs temperature adjustment control so that the maximum temperature T _MAX and the minimum temperature T _MIN of the battery module 31 are within this region F.

[4. flowchart]
Next, an example of a temperature adjustment control procedure performed by the vehicle ECU 15 will be described with reference to FIG. This flowchart operates in a predetermined cycle (for example, a cycle of several ms). Each of the following steps is performed by each function (means) assigned to the hardware of the computer being operated by software (computer program).
When the engine 2 is started by turning on the ignition switch of the vehicle 1 by the driver, the temperature control device starts the following control flow.

As shown in FIG. 4, in step S <b> 10, temperature information of each battery module 31 is acquired by the plurality of temperature sensors 32. Next, in step S20, a maximum temperature _TMAX and a minimum temperature _TMIN are selected from the acquired temperature information. The following steps S30 to S130 are steps determined by the temperature control unit 15e, and it is determined which control is to be performed by the vehicle ECU 15. Further, the following steps S140 to S190 are control steps performed by the vehicle ECU 15, and A to F correspond to the areas A to F in FIG. 3A, and control of each area is performed. Means.

First, in step S30, it is determined whether or not the temperature difference ΔT between the maximum temperature T _MAX and the minimum temperature T _MIN is equal to or greater than the first switching temperature difference ΔT ₁ . This determination corresponds to the above condition (6). When the temperature difference ΔT is greater than or equal to the first switching temperature difference ΔT ₁ , the process proceeds from the YES route to step S40, and it is determined whether or not the maximum temperature T _MAX is less than the required cooling temperature T _C. The maximum temperature T _MAX is the time of less than main cooling temperature T _C, the flow advances from YES route to step S50, whether or not the lowest temperature T _MIN is essential heating temperature T _H above is determined. Minimum temperature T _MIN is when the above main heating temperature T _H, the process proceeds from YES route to step S60, whether the temperature difference [Delta] T is equal to the second switching temperature difference [Delta] T ₂ or more is determined.

If the temperature difference [Delta] T is determined to be the second switching temperature difference [Delta] T ₂ or more in step S60, the flow advances from YES route to step S140, the first temperature-equalizing control (region D) is carried out. On the other hand, if it is determined in step S60 that the temperature difference ΔT is not greater than or equal to the second switching temperature difference ΔT ₂ (that is, the temperature difference ΔT is less than the second switching temperature difference ΔT ₂ ), the process proceeds from the NO route to step S150. Second temperature equalization control (region E) is performed. That is, if YES in step S30, YES in step S40, and YES in step S50, the above condition (7) is satisfied. Further, when the result is YES in step S60, the above condition (10) is satisfied, and when the result is NO in step S60, the above condition (11) is satisfied.

If it is determined in step S40 that the maximum temperature T _MAX is not less than the required cooling temperature T _C , the process proceeds from the NO route to step S70, and whether or not the minimum temperature T _MIN is less than the first switching temperature T ₁ is determined. Determined. When the minimum temperature T _MIN is lower than the first switching temperature T ₁ , the process proceeds from the YES route to step S140, and the first temperature equalization control (region D) is performed. That is, if YES in step S30, NO in step S40, and YES in step S70, the above condition (8) is satisfied.

Further, when the minimum temperature T _MIN is determined not to be needed heating temperatures T _H than in step S50, the process proceeds from NO route to step S80, whether the highest temperature T _MAX is equal to the second switching temperature T ₂ or higher Determined. The maximum temperature T _MAX Conjunction when the second switching temperature T ₂ above proceeds from YES route to step S140, the first temperature-equalizing control (region D) is carried out. That is, if YES in step S30, YES in step S40, NO in step S50, and YES in step S80, the above condition (9) is satisfied.

On the other hand, if it is determined in step S70 that the minimum temperature T _MIN is not lower than the first switching temperature T ₁ , the process proceeds from the NO route to step S160, and cooling control (region A) is performed. That is, in the case of NO in step S40 and NO in step S70, the above condition (1) is satisfied. Further, when the maximum temperature T _MAX is determined not to be the second switching temperature T ₂ or higher in step S80, the process proceeds from NO route to step S90, whether the highest temperature T _MAX is lower than the third switching temperature T ₃ Is determined. That is, in the case of NO in step S50 and NO in step S80, the above condition (2) is satisfied.

If in step S90 the highest temperature T _MAX is determined to be less than the third switching temperature T _3, the flow advances from YES route to step S100, the minimum temperature T _MIN whether less than the fourth switching temperature T ₄ is determined . When the minimum temperature T _MIN is lower than the fourth switching temperature T ₄ , the process proceeds from the YES route to step S170, and the first heating control (area B) is performed. That is, in the case of YES in step S90 and YES in step S100, the above condition (3) is satisfied.

On the other hand, if the maximum temperature T _MAX in step S90 is determined not to be less than the third switching temperature T _3, and, in step S100, if the minimum temperature T _MIN is determined to be not less than the fourth switching temperature T ₄ In any case, the process proceeds from the NO route to step S180, and the second heating control (region C) is performed. That is, if NO in step S50, YES in step S80 and NO in step S90, the above condition (4) is satisfied. If NO in step S50, YES in step S90 and NO in step S100, the above conditions are satisfied. Satisfy (5).

Further, when the temperature difference [Delta] T is determined not to be the first switching temperature difference [Delta] T ₁ or more, the process proceeds from NO route to step S110, whether the highest temperature T _MAX is lower than the main cooling temperature T _C is in step S30 Determined. The maximum temperature T _MAX is the time of less than main cooling temperature T _C, the flow advances from YES route to step S120, whether or not the lowest temperature T _MIN is essential heating temperature T _H above is determined. When the minimum temperature T _MIN is equal to or higher than the required heating temperature T _H , the process proceeds from the YES route to step S190, and holding control (region F) is performed. That is, if NO in step S30, YES in step S110, and YES in step S120, the above condition (12) is satisfied.

On the other hand, when the minimum temperature T _MIN is determined not to be needed heating temperatures T _H above in step S120, the process proceeds from NO route to step S130, whether or not the lowest temperature T _MIN is less than the fourth switching temperature T ₄ is Determined. When the minimum temperature T _MIN is lower than the fourth switching temperature T ₄ , the process proceeds from the YES route to step S170, and the first heating control (area B) is performed. If the minimum temperature T _MIN is not lower than the fourth switching temperature T ₄ , the process proceeds from the NO route to step S180, where the second heating control (area C) is performed. That is, here the case of NO in NO and step S120 in step S30, since the highest temperature T _MAX is the second switching temperature T less than _2, satisfies the above condition (2), above the determination result of step S130 Condition (3) or (5) is satisfied.

On the other hand, when the maximum temperature T _MAX is not lower than the required cooling temperature T _C in step S110, the process proceeds from the NO route to step S160, and cooling control (region A) is performed. That is, here, if NO in step S30 and NO in step S110, the minimum temperature T _MIN is equal to or higher than the first switching temperature T ₁ , so the above condition (1) is satisfied.

  When the control in steps S140 to S190 is performed, the process proceeds to step S200, where it is determined whether or not the ignition switch is off. If it is on, the process proceeds to the NO route and returns, and control is performed again from step S10. A flow is performed. If the ignition switch is off, the control flow ends.

[5. effect]
Therefore, according to the temperature control apparatus, the battery 10 having the plurality of battery modules 31 acquires the maximum temperature T _MAX and the minimum temperature T _MIN among the temperatures detected by the plurality of temperature sensors 32, and the maximum temperature T Temperature equalization control is performed when the temperature difference ΔT between the _MAX and the minimum temperature T _MIN is equal to or greater than a predetermined first switching temperature difference ΔT ₁ . In this temperature equalization control, the shutter valve 24 and the fan 25 are controlled so that air circulates between the battery case 30 and the heater 11 in a state where the operation of the heater 11 is stopped. The temperature difference between the plurality of battery modules 31 can be eliminated without adding or removing heat from the outside to the module 31 (that is, without heating or cooling).

That is, when the temperature difference ΔT between the plurality of battery modules 31 is equal to or greater than the first switching temperature difference ΔT ₁ , the cooling control and the heating control are repeated in order to perform the temperature equalization control instead of the cooling control and the heating control. There is no such a situation (in other words, the occurrence of hunting is suppressed), and the temperature difference ΔT can be reliably eliminated.

In addition, as shown in FIG. 3B, until now, when the maximum temperature T _MAX of the plurality of battery modules 31 is equal to or higher than the required cooling temperature T _C, which is a temperature that requires cooling, cooling control has been performed. (Region A). Since this cooling control is to cool the battery by sending cold air from the outside of the battery case to the internal battery, the battery arranged on the upstream side of the air flow is well cooled and the temperature is likely to decrease. On the other hand, the batteries arranged on the downstream side are less likely to be cooled because the air whose temperature has increased on the upstream side flows and the temperature is unlikely to decrease. Therefore, in the region A of FIG. 3B where the cooling control is performed, the rate of decrease of the maximum temperature T _MAX is smaller than the rate of decrease of the minimum temperature T _MIN , and the maximum temperature T _MAX and the minimum temperature are indicated by arrows. The temperature difference from T _MIN was increasing.

On the other hand, in this temperature control apparatus, even if the maximum temperature T _MAX is equal to or higher than the required cooling temperature T _C and the minimum temperature T _MIN is lower than the first switching temperature T ₁ , the temperature is equalized instead of the cooling control. Control is performed (region D in FIG. 3A). Thus, the maximum temperature T heat with the battery module 31 a high temperature such as a battery module 31 of the _MAX, can be moved to a lower battery module 31 temperature such as a battery module 31 of the lowest temperature T _MIN. That is, while lowering the temperature of the battery module 31 having a high temperature, the temperature of the battery module 31 having a low temperature can be increased, and the temperature difference between the plurality of battery modules 31 is prevented from increasing and gradually between the batteries. Temperature difference can be eliminated.

Further, as shown in FIG. 3 (b), the past, when the maximum temperature T _MAX minimum temperature T _MIN of a plurality of battery modules 31 is less than the main heating temperature T _H is lower than a main cooling temperature T _C Heating control was performed (area B). In this heating control, hot air is sent from the outside of the battery case to the internal battery to heat the battery. Therefore, the battery arranged on the upstream side of the air flow is often heated and easily rises in temperature. On the other hand, the batteries arranged on the downstream side are less likely to be heated because the air whose temperature has decreased on the upstream side flows, and the temperature is unlikely to rise. Therefore, in the region B shown in FIG. 3 (b) the heating control is performed, a small rate of increase in the minimum temperature T _MIN relative increase rate of the maximum temperature T _MAX, the maximum temperature T _MAX and the minimum temperature as indicated by the arrow The temperature difference from T _MIN was increasing.

In contrast, in the temperature control apparatus, even lower than the lowest temperature T _MIN is essential heating temperature T _H, is lower than the maximum temperature T _MAX is essential cooling temperature T is lower than the _C second switching temperature T ₂ Then, temperature equalization control is performed instead of heating control (region D in FIG. 3A). Thus, the maximum temperature T heat with the battery module 31 a high temperature such as a battery module 31 of the _MAX, can be moved to a lower battery module 31 temperature such as a battery module 31 of the lowest temperature T _MIN. That is, while lowering the temperature of the battery module 31 having a high temperature, the temperature of the battery module 31 having a low temperature can be increased, and the temperature difference between the plurality of battery modules 31 is prevented from increasing and gradually between the batteries. Temperature difference can be eliminated.

Furthermore, as shown in FIG. 3 (b), the past, when the lowest temperature T _MIN is less than the main heating temperature T _H, the maximum temperature T _MAX is a cooling control depending on whether main cooling temperature T _C or heating Control was switched and implemented. Therefore, in this temperature range, there is a problem that cooling control and heating control are repeatedly performed (that is, hunting is likely to occur).
On the other hand, the present temperature adjustment device performs the temperature equalization control between the cooling control and the heating control (in other words, does not set the temperature condition for switching between the cooling control and the heating control), so that the cooling control is performed. Switching between heating and heating control does not occur frequently, and hunting can be suppressed.

When the temperature equalization control is performed, if the temperature difference ΔT is less than the second switching temperature difference ΔT ₂ , the strength of the fan 25 is decreased to reduce the air flow rate (in other words, the temperature difference The temperature of the fan 25 is strong until ΔT becomes the second switching temperature difference ΔT _2, and the strength of the fan 25 is weakened if it becomes less than the second switching temperature difference ΔT ₂ ). As the temperature becomes smaller, the temperature can be gradually made uniform.

Further, since the minimum temperature T _MIN to practice the heating control when less than a main heating temperature T _H, it is possible to suppress the deterioration of reduction and electric power consumption of the input and output performance of the battery 10.
Further, when this heating control is performed, if the maximum temperature T _MAX is less than the second switching temperature T ₂ and the third switching temperature T ₃ or more, or the minimum temperature T _MIN is less than the required heating temperature T _H and the fourth temperature. When the temperature is higher than the switching temperature T _4, the second heating control (weak heating control) is performed by reducing the strength of the heater 11, so that the gentle heating control is performed when the temperature of the battery module 31 increases as a whole. By doing so, soft landing control can be performed.

Similarly, when this heating control is performed, if the maximum temperature T _MAX is less than the second switching temperature T ₂ and the third switching temperature T ₃ or more, or the minimum temperature T _MIN is less than the required heating temperature T _H and the first switching temperature T ₃ . If four switching temperature T ₄ or more, for carrying out the second heating control by weakening the strength of the fan 25 (weak heating control), the gradual heating control when the temperature have generally higher in the battery module 31 By implementing this, soft landing control can be performed.

Further, when the temperature difference ΔT is less than the first switching temperature difference ΔT ₁ , the maximum temperature T _MAX is less than the required cooling temperature T _C, and the minimum temperature T _MIN is _equal to or higher than the required heating temperature T _H , this state is maintained. Since the control is performed, the state of the battery 10 can be brought into the most suitable state (that is, the optimum state for input / output performance, power consumption, battery durability, etc.).

[6. Others]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above embodiment, when the second heating control is performed, the strength of the fan 25 and the heater 11 are both set to low. However, the second heating control is not limited to this, and either the fan 25 or the heater 11 is performed. Only the strength of may be low. For example, in the second heating control when the strength of the fan 25 is high and the strength of the heater 11 is low, the temperature of the air flowing in from the circulation passage 23 can be made lower than that in the first heating control. The temperature rise of the battery module 31 on the side can be made slower than the first heating control, and the heating control can be made gentler than the first heating control. Further, in the second heating control when the strength of the fan 25 is low and the strength of the heater 11 is high, the flow rate of air flowing in from the circulation flow path 23 can be made smaller than in the first heating control. Also in this case, the temperature rise of the battery module 31 on the upstream side can be made slower than the first heating control, and the heating control can be made gentler than the first heating control.

  Further, if the strength of the fan 25 and the heater 11 is multi-stage, it is possible to perform the weak heating control and the weak temperature equalization control, but even if these strengths cannot be switched, the heating control and Since temperature equalization control can be performed, the fan 25 and the heater 11 may be capable of performing only on / off control.

  In the above embodiment, the flow path switching means is the shutter valve 24 provided at the connection portion between the discharge flow path 22 and the circulation flow path 23, but the flow path switching means is not limited to this. For example, a shutter valve is provided in each of the supply flow path 21 and the circulation flow path 23 on the downstream side of the heater 11, and the air flow and circulation for releasing the air guided into the battery case 30 by switching between these are provided. You may comprise so that the flow of the air which circulates through the flow path 23 may be switched.

Further, the arrangement of the fan 25 is not limited to the discharge flow path 22 and may be any arrangement that can guide air into the battery case 30 (that is, it is only necessary to form an air flow in the battery case 30).
Moreover, in the said embodiment, although the temperature content is divided and the control content is switched on the temperature conditions as shown to the map of Fig.3 (a), the division of a region is not restricted to this, Each temperature is changed. It may be changed by changing the conditions.

Moreover, in the said embodiment, although the battery 10 is comprised as an assembled battery in which the several battery module 31 was accommodated in the battery case 30, an assembled battery is a battery module which accommodated the several battery cell in the container. You may comprise, and the number of the battery cells and battery modules to be accommodated can be arbitrarily selected.
Further, the battery 10 may not be provided in the vehicle interior 1a, and may be provided outside the vehicle interior 1a, for example, below the vehicle body. In this case, the battery 10 is cooled by taking in outside air. Further, the heater 11 and the vehicle ECU 15 may not be provided in the passenger compartment 1a.

  Moreover, although the said embodiment demonstrated the battery 10 mounted in the parallel type hybrid vehicle as an example, the vehicle 1 is not restricted to a hybrid vehicle, What is necessary is just electric vehicles, such as an electric vehicle. Further, the battery 10 may not be mounted on the vehicle.

1 vehicle 9 air conditioner 10 battery (assembled battery)
11 Heater 14 Air-conditioner ECU
15 Vehicle ECU
15a Battery management unit (battery management unit, BMU)
15b Fan control unit (fan control means)
15c Heater control unit (heater control means)
15d Shutter control unit (flow path switching means)
15e Temperature controller (temperature control means)
20 piping 21 supply flow path 22 discharge flow path 23 circulation flow path 24 shutter valve (flow path switching means)
25 Fan 30 Battery case (container)
31 Battery module (battery)
32 temperature sensor T _C-cooled temperature
T _H required heating temperature
T _MAX maximum temperature
T _MIN minimum temperature

Claims (8)

A battery pack temperature control apparatus comprising: a fan that guides air into a container that houses a plurality of batteries; and a heater that heats the air flowing into the container,
A flow path switching means for switching between a flow of air that discharges the air guided into the container to the outside and a flow of air that circulates the air guided into the container through the heater and into the container;
A plurality of temperature sensors that respectively detect the temperatures of the plurality of batteries;
Temperature control means for adjusting the temperature of the assembled battery based on a maximum temperature and a minimum temperature among the temperatures of the plurality of batteries detected by the plurality of temperature sensors ;
The fan has stepwise strength, and includes fan control means for controlling the flow rate of air guided into the container by adjusting the strength of the fan ,
The temperature control means includes
First switching in which a temperature difference between the maximum temperature and the minimum temperature is equal to or greater than a predetermined first switching temperature difference , the maximum temperature is equal to or higher than a predetermined cooling temperature and the minimum temperature is higher than a predetermined heating temperature. When the temperature is lower than the temperature, or when the maximum temperature is equal to or higher than the second switching temperature lower than the cooling required temperature and the minimum temperature is lower than the heating required temperature , the heater is stopped and the fan is operated. In the state, the temperature switching control means for circulating air between the inside of the container and the heater by the flow path switching means ,
When the temperature difference is less than the second switching temperature difference, which is higher than the first switching temperature difference, the heater is stopped and the strength of the fan is reduced to reduce the strength of the fan by the flow path switching means. A temperature adjusting device for an assembled battery, characterized in that it performs weak temperature equalization control for circulating air between Circulating said temperature control means, when the minimum temperature is lower than the main heating temperature, the air between the heater and the vessel by the flow path switching unit in a state in which both operating said heater and said fan which comprises carrying out the heating control for the temperature adjustment device for a battery pack according to claim 1, wherein. The heater has stepwise strength, and includes heater control means for controlling the temperature of air flowing into the container by adjusting the strength of the heater,
Said temperature control means, when said maximum temperature is above lower third switching temperature than the second switching temperature and less than the second switching temperature, or, than the minimum temperature less than said main heating temperature and the main heating temperature If the temperature is higher than the lower fourth switching temperature, the fan is operated to weaken the strength of the heater and the flow switching means performs weak heating control to circulate air between the container and the heater. The temperature adjusting device for an assembled battery according to claim 2 . Before SL temperature control means, said maximum case temperature is above lower third switching temperature than the second switching temperature and less than the second switching temperature or the minimum temperature is the main heating temperature and less than said main heating temperature When the temperature is equal to or higher than the lower fourth switching temperature, the heater is operated to weaken the strength of the fan and the flow switching means performs weak heating control to circulate air between the container and the heater. The temperature adjusting device for an assembled battery according to claim 2 or 3, wherein A battery pack temperature control apparatus comprising: a fan that guides air into a container that houses a plurality of batteries; and a heater that heats the air flowing into the container,
A flow path switching means for switching between a flow of air that discharges the air guided into the container to the outside and a flow of air that circulates the air guided into the container through the heater and into the container;
A plurality of temperature sensors that respectively detect the temperatures of the plurality of batteries;
Temperature control means for adjusting the temperature of the assembled battery based on a maximum temperature and a minimum temperature among the temperatures of the plurality of batteries detected by the plurality of temperature sensors ;
The heater has stepwise strength, and comprises a heater control means for controlling the temperature of the air flowing into the container by adjusting the strength of the heater ,
The temperature control means includes
When the temperature difference between the maximum temperature and the minimum temperature is greater than or equal to a predetermined first switching temperature difference, the heater is turned off and the fan is turned on in the container and the container by the flow path switching means. conduct temperature leveling control circulating air between the heater,
When the minimum temperature is lower than a predetermined heating temperature, heating control is performed such that air is circulated between the container and the heater by the flow path switching unit in a state where both the heater and the fan are operated. And
When the maximum temperature is lower than a second switching temperature lower than a predetermined cooling temperature and a third switching temperature lower than the second switching temperature, or the minimum temperature is lower than the heating temperature and the heating temperature When the temperature is higher than the lower fourth switching temperature, the fan is operated to weaken the heater, and the flow switching means performs weak heating control for circulating air between the container and the heater. A temperature control device for an assembled battery. The fan has stepwise strength, and includes fan control means for controlling the flow rate of air guided into the container by adjusting the strength of the fan,
Said temperature control means, the case where the maximum temperature is above the second switching temperature and less than before Symbol third switching temperature, or if the minimum temperature is above the main heating temperature and less than before Symbol fourth switching temperature, which comprises carrying out the weak heating control circulating air between the heater and the vessel by the flow path switching means weaken the strength of the fan is operated with the heater, according to claim 5, wherein Battery pack temperature control device. A battery pack temperature control apparatus comprising: a fan that guides air into a container that houses a plurality of batteries; and a heater that heats the air flowing into the container,
A flow path switching means for switching between a flow of air that discharges the air guided into the container to the outside and a flow of air that circulates the air guided into the container through the heater and into the container;
A plurality of temperature sensors that respectively detect the temperatures of the plurality of batteries;
Temperature control means for adjusting the temperature of the assembled battery based on a maximum temperature and a minimum temperature among the temperatures of the plurality of batteries detected by the plurality of temperature sensors ;
The fan has stepwise strength, and includes fan control means for controlling the flow rate of air guided into the container by adjusting the strength of the fan ,
The temperature control means includes
When the temperature difference between the maximum temperature and the minimum temperature is greater than or equal to a predetermined first switching temperature difference, the heater is turned off and the fan is turned on in the container and the container by the flow path switching means. conduct temperature leveling control circulating air between the heater,
When the minimum temperature is lower than a predetermined heating temperature, heating control is performed such that air is circulated between the container and the heater by the flow path switching unit in a state where both the heater and the fan are operated. And
When the maximum temperature is lower than a second switching temperature lower than a predetermined cooling temperature and a third switching temperature lower than the second switching temperature, or the minimum temperature is lower than the heating temperature and the heating temperature When the temperature is equal to or higher than the lower fourth switching temperature, the heater is operated to weaken the strength of the fan and the flow switching means performs weak heating control to circulate air between the container and the heater. A temperature control device for an assembled battery. Said temperature control means, when said maximum temperature and is below the main cooling temperature said temperature difference is less than the said first switching temperature difference minimum temperature is above the main heating temperature, operation of the fan and the heater The assembled battery temperature control device according to any one of claims 1 to 7, wherein holding control for holding the flow path switching means in a current state is performed by stopping both of them.

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