JP5025039B2 - Battery temperature control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a battery temperature control device.
[0002]
[Prior art]
In recent years, electric vehicles and hybrid vehicles have attracted attention because of energy saving and environmental considerations. Since electric vehicles and hybrid vehicles use a large number of batteries as power sources, the performance of the batteries is important. In order for the battery to fully perform and maintain its performance, it is necessary to adjust the temperature of the battery to an appropriate temperature. In particular, the battery needs to be cooled because it generates a lot of heat during charging or discharging and may become hot.
[0003]
Conventionally, the temperature of the battery has been controlled by natural air cooling, but this is not sufficient. Japanese Patent Application Laid-Open No. 7-6796 discloses that the bottom wall of the case for storing the battery and the partition wall between the batteries have a hollow structure to form a ventilation path. In addition, there is disclosed an apparatus in which a refrigerant pipe is inserted here and an air flow is formed by a blower fan to cool the battery.
[0004]
[Problems to be solved by the invention]
However, in the technique disclosed in Japanese Patent Laid-Open No. 7-6796, the bottom wall and the partition wall of the case have a hollow structure, and in order to increase the cooling capacity, the refrigerant pipe is inserted through the entire wall surrounding the battery, Since a fan is used, the structure is complicated and it cannot be denied that the size is increased.
[0005]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a compact battery temperature control device with high temperature control efficiency and a simple configuration.
[0006]
[Means for Solving the Problems]
According to the first aspect of the present invention, in the battery temperature control device that cools the battery, the battery is held in a first heat transfer plate on which the battery is placed, and the heat transfer plate is erected and is in close contact with the side surface of the battery. This is performed by a battery holding frame having a second heat transfer plate and a pipe line in close contact with the lower surface of the first heat transfer plate. In addition, the battery holding frame is stored in a state where the battery is held by a sealed case made of a heat insulating material. The heat transport material that exchanges heat with the heat transfer plate is circulated in the pipe line through the pipe wall by the distribution means. The battery holding frame has a configuration in which the second heat transfer plate is arranged on the upper surface of the first heat transfer plate so that both are thermally connected, and the battery and the second heat transfer plate are also connected. The heat plates are alternately arranged and stacked, and the second heat transfer plates are brought into close contact with both side surfaces of the battery ,
The distribution means includes a compressor that heats a refrigerant, which is a heat transport material, at a high temperature and a high pressure, a condenser that liquefies the high temperature and pressure refrigerant, and an expansion valve that expands the liquefied refrigerant and lowers the temperature. The pressure detecting means for detecting the pressure in the refrigerant pipe through which the refrigerant flows is provided in the refrigerant pipe located in the sealed case. Installed .
[0007]
The heat transport material exchanges heat with the battery via the pipe wall of the pipe line and the heat transfer plate, and controls the temperature of the battery. At this time, heat transfer from the battery to the pipe line is performed only by conduction in the heat transfer plate without passing through air having poor heat conduction. Moreover, since the battery holding frame itself is insulated by the sealed case, it is not affected by the ambient temperature outside the case. Therefore, the temperature of the battery can be controlled efficiently.
[0008]
In addition, the duct itself that is in close contact with the lower surface of the first heat transfer plate increases the strength of the entire battery holding frame, and there is no ventilation path or blower fan inside the case wall. It can be made compact.
A large amount of heat generated from the battery can be efficiently removed by the low-temperature refrigerant obtained by the refrigeration cycle. Further, since the inside of the sealed case becomes relatively low during battery cooling, thermal loss in the expansion valve can be suppressed. Furthermore, even if the outside air becomes cold, the temperature in the sealed case is relatively high compared to the outside air. Therefore, it is possible to appropriately determine the presence or absence of the refrigerant in the refrigerant pipe from the detected pressure of the pressure detecting means placed in the sealed case.
[0011]
In the invention according to claim 2, the member which makes the battery and the opposing surface of the 2nd heat exchanger plate contact is arranged.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
( Basic form)
Figure 1 is a basic embodiment of the present invention in FIG. 2, showing the basic structure of battery-temperature control apparatus applied to a vehicle. The battery temperature control device includes a refrigeration cycle for controlling the temperature of the battery 1, and includes a compressor 21, a condenser 22, a receiver 23, an expansion valve 24a, and a battery cooler 3a as a battery holding frame, which are arranged in this order as refrigerant piping. 4 are connected.
[0020]
The compressor 21 is driven by the belt 71 driven by the engine 71 and operates to compress the vaporized refrigerant to a high temperature and high pressure. The capacitor 22 dissipates the heat of the high-temperature high-pressure refrigerant to the outside air supplied from the front of the vehicle and liquefies the high-temperature high-pressure refrigerant. The receiver 23 separates gas and liquid and stores excess liquefied refrigerant. The expansion valve 24a reduces the pressure of the liquefied refrigerant to low temperature and low pressure. The compressor 21, the condenser 22, the receiver 23, and the expansion valve 24a constitute the circulation means 2, and the low-temperature and low-pressure refrigerant from the expansion valve 24a is used for cooling the battery 1 in the battery cooler 3a.
[0021]
Further, the compressor 21, the condenser 22, and the receiver 23 are also used as an air conditioner for cooling the interior of the passenger compartment 73, and the refrigerant pipe 4 branches in the middle, and another expansion valve 24b in parallel with the expansion valve 24a and the battery cooler 3a An evaporator 3b is provided.
[0022]
The refrigerant pipe 4 is provided with two electromagnetic valves 5a and 5b. The electromagnetic valve 5a permits or prohibits the flow of refrigerant to the battery cooler 3a, and the electromagnetic valve 5b allows the flow of refrigerant to the evaporator 3b. Or ban. The solenoid valves 5a and 5b are controlled by an unillustrated ECU, and low temperature and low pressure liquefied refrigerant flows through one or both of the battery cooler 3a and the evaporator 3b by switching between opening and closing of the solenoid valves 5a and 5b. Yes.
[0024]
The evaporator 3 b is provided in a duct 74 that opens into the passenger compartment 73. The duct 74 is provided with a blower fan 75 for blowing air on the upstream side, so that air radiated to the evaporator 3 b is supplied into the passenger compartment 73. The air taken in by the blower fan 75 is selected between inside air and outside air by switching the damper 76.
[0025]
The battery cooler 3 a is stored together with the battery 1 in a sealed case 6 that stores the battery 1. The case 6 is configured to be in a hermetically sealed state when covered, and the reciprocation of the refrigerant to the battery cooler 3a is performed via the joint portion 43 of the refrigerant pipe 4 attached to the outer wall surface of the case 6, and the joint portion 43, an outward piping 41 for supplying the refrigerant to the battery cooler 3a and a return piping 42 for recovering the refrigerant from the battery cooler 3a extend through the wall of the case 6. The case 6 is made of a heat insulating material, and in combination with the sealed structure, the heat insulating property in the case 6 is enhanced.
[0026]
The battery cooler 3a holds the battery 1 with two types of aluminum members 31 and 32. The first member 31 is a rectangular plate-like member that is slightly smaller than the planar shape of the case 6 and is installed horizontally. The second member 32 is substantially equal in width to the member 31 and is processed to have an L-shaped cross section. A plurality of second members 32 are used, and the long side portion 321 that is the second heat transfer plate is erected on the upper surface of the member 31 that is the first heat transfer plate at intervals in the form of a screen. The member 31 and the member 32 are integrated by brazing the short side portion 322 of the member 32 to the surface of the member 31. Hereinafter, the member 31 is referred to as a heat transfer substrate, and the long side portion 321 of the member 32 is referred to as a heat transfer fin.
[0027]
The shape and arrangement interval of the heat transfer fins 321 are matched to the shape of the battery 1, the batteries 1 are arranged one by one between two adjacent heat transfer fins 321, and the bottom surface of the battery 1 is the short side of the member 32. The side surface 101 of the battery 1 is in contact with the heat transfer fin 321. Two U-shaped stays 34 are provided surrounding the heat transfer fins 321 and the outer periphery of the battery 1. The ends 341 of both stays 34 are bent in an L shape, and are opposed to the ends 341 of the other stay 34, respectively. Bolts 35 are inserted into a pair of opposed end portions 341 and bolts 35 and nuts 36 are screwed together to fix the battery 1 to the battery cooler 3 a and to face the battery 1 and the heat transfer fins 321. The comrades are in close contact with each other to increase heat transfer. Note that heat transfer grease may be applied to the opposing surfaces of the battery 1 and the heat transfer fins 321 to further enhance the heat transfer property. Further, an insulating coating may be formed on the heat transfer fins 321 so that when the battery 1 leaks liquid at a plurality of locations, it is possible to enhance resistance to a short circuit that occurs through the heat transfer fins 321 having good conductivity.
[0028]
Below the heat transfer substrate 31, six fin tubes 331 and 332 are arranged. The fin tubes 331 and 332 are tubular members having a rectangular cross section, and their upper surfaces are brazed to the lower surface of the heat transfer substrate 31. A large number of fins protrude from the inner peripheral surfaces of the fin tubes 331 and 332 to widen the heat receiving area. If the close contact between the fin tubes 331 and 332 and the heat transfer substrate 31 is sufficient, the fin tubes 331 and 332 and the heat transfer substrate 31 may be fixed to the case 6 respectively. The fin tubes 331 and 332 are routed in parallel to each other in the direction of crossing the heat transfer fins 321 at equal intervals, and are equally disposed below the battery 1. The fin tube 331 and the fin tube 332 adjacent to each other are connected to each other by a turn pipe 333 at one end, and these are integrated by brazing. The two fin tubes 331 and 332 and the turn pipe 333 are combined to form one U-shaped heat exchange pipe line 33.
[0029]
One end of each of the three sets of pipes 33 is connected to a common forward pipe 41 and communicates with the expansion valve 24 a via the forward pipe 41. The other end is connected to a common return line 42 and communicates with the compressor 21 via the return line 42. That is, the low-temperature and low-pressure refrigerant from the expansion valve 24a is divided into three pipe lines 33 from the forward pipe 41 and is joined again by the return pipe 42.
[0030]
The operation of the battery temperature control device will be described. In order to cool the battery 1, the electromagnetic valve 5a is opened, and the refrigerant circuit from the compressor 21 through the condenser 22, the receiver 23, the expansion valve 24a, and the battery cooler 3a is returned to the compressor 21 again. Thereby, the low-temperature and low-pressure liquefied refrigerant flows through the fin tubes 331 and 332 of the battery cooler 3a as shown by arrows in FIG. The liquefied refrigerant receives heat generated by the battery 1 through the heat transfer substrate 31 and the fin tubes 331 and 332 walls or through the heat transfer fins 321, the heat transfer substrate 31 and the fin tubes 331 and 332 walls, The battery 1 is cooled. At this time, heat transfer from the battery 1 to the fin tubes 331 and 332 is performed only by conduction in the heat transfer fins 321 and the heat transfer substrate 31. Moreover, the battery cooler 3a itself is insulated by the case 6, and a gap 601 is provided between the case 6 and the battery cooler 3a to restrict the movement of heat from the wall of the case 6 to the battery cooler 3a. Therefore, the battery 1 can be efficiently cooled.
[0031]
Further, by forming the heat exchange pipe line 33 in a U shape, the refrigerant flow direction is reversed between the adjacent fin tube 331 and the fin tube 332, and the upstream part near the forward pipe 41 and the return pipe 42. Near the downstream part, and the midstream parts that are separated from both the outgoing pipe 41 and the return pipe 42 come close. Since the refrigerant flows through the pipe line 33 while performing heat exchange, and the heat exchange capacity of the refrigerant decreases as it goes downstream of the pipe line 33, the heat exchange capacity in a portion close to the forward pipe 41 and the backward pipe 42, The heat exchanging capacity in the part away from the forward piping 41 and the backward piping 42 is substantially equal. Thereby, in any battery 1, it can cool equally and can prevent insufficient cooling and overcooling.
[0032]
In addition, the duct 33 that is in close contact with the lower surface of the heat transfer board 31 reinforces the heat transfer board 31 with a beam to enhance the overall strength of the battery cooler 3a, and the case wall does not have a hollow structure and blows air. Since no fan is provided, the overall configuration can be made simple and compact.
[0033]
The battery cooler includes a first heat transfer plate on which the battery is placed, a second heat transfer plate that stands on the heat transfer plate and is in close contact with the side surface of the battery, and a lower surface of the first heat transfer plate. A configuration including a heat exchange pipe that is in close contact with each other is sufficient, and FIG. 3 shows a modification of the battery cooler. In the figure, the parts denoted by the same reference numerals as those in the configuration of FIG. 1 operate substantially in the same manner, and therefore, differences from the configuration of FIG. 1 will be mainly described. The member 37 is formed by bending a rectangular aluminum plate into a U-shaped cross section, has two long side portions 371 facing each other, and a space sandwiched between the long side portion 371 and the short side portion 372 that are heat transfer fins is The shape of the battery 1 is adjusted. The member 37 is disposed on the surface of the heat transfer substrate 31 at the same interval as the opposing interval of the long side portion 371, and the short side portion 372 is brazed to the heat transfer substrate 31. The battery 1 is disposed between the two long side portions 371.
[0034]
The battery cooler having this configuration has substantially the same shape as that of FIG. 1, but two heat transfer fins 371 are formed on each heat transfer member 37, so that the number of parts can be reduced to about half. it can.
[0035]
Moreover, although the battery cooler shown to FIG. 1, FIG. 3 makes the heat-transfer board | substrate and the heat-transfer fin separate, it is good also as an integral structure. The example of the battery cooler concerning FIG. 4 is shown. The member 38 is formed by connecting a bottom plate 381 as a first heat transfer plate and a top plate 382 to form a plurality of vertical walls 383 as second heat transfer plates. They are arranged parallel to each other. This integral member 38 can be manufactured at a time, for example, by extrusion molding using a mold having a ladder shape in section. The structure is sturdy and the number of parts can be further reduced. The battery 1 is fitted in a space defined by the bottom plate 381, the top plate 382, and the vertical wall 383.
[0036]
(Implementation form)
It shows the configuration of a battery temperature control apparatus according to the implementation embodiments of the present invention in FIG. In the figure, the portion denoted by the same numbers as in FIG. 1 is the same operation as substantially the basic embodiment will be described focusing on differences from the basic form. The expansion valve 24 a is installed in the portion of the refrigerant pipe 4 that is routed inside the case 6. In addition, a pressure sensor 8 is provided at a portion around the case 6 of the refrigerant pipe 4 at a position immediately downstream of the battery cooler 3a of the refrigerant pipe 4, and before the compressor 21 is started, that is, the battery 1 starts cooling. Before, the pressure in the refrigerant pipe 4 is measured from the detection signal of the pressure sensor 8 in the ECU, and if the pressure value is below a preset lower limit value, it is determined that the refrigerant is missing.
[0037]
When the refrigerant becomes low temperature and low pressure in the expansion valve 24a, the refrigerant absorbs heat from the installation atmosphere of the expansion valve 24a and causes a thermal loss. The loss is larger as the installation atmosphere temperature of the expansion valve 24a is higher. In the present embodiment, the inside of the case 6 in which the expansion valve 24a is placed is insulated, and the battery 1 is cooled at a temperature lower than the outside temperature of the case 6, so that the thermal loss in the expansion valve 24a can be kept small. .
[0038]
Further, even when the pressure value obtained by the pressure sensor 8 is lower than the lower limit value, when the outside air is greatly reduced in extremely cold regions, the saturated vapor pressure of the refrigerant may be lower than the atmospheric pressure depending on the temperature. Normally, it cannot be determined that the refrigerant is missing. In the present embodiment, the inside of the case 6 where the pressure sensor 8 is placed is insulated, and the battery 1 also generates heat. The temperature is relatively higher than the outside of the case 6 before the compressor 21 is started. It is possible to detect the missing refrigerant.
[0039]
Incidentally, the refrigeration cycle in the above you facilities embodiment may be batteries only.
[0040]
In addition, the heat exchange pipe is formed in a U-shape, but depending on the required uniformity of heat exchange capacity, one end of the straight pipe is connected to the forward pipe and the other end is connected to the return pipe. Also good.
[Brief description of the drawings]
FIG. 1A is an overall configuration diagram of a battery temperature control device as a basic configuration of the present invention, and FIG. 1B is a view as viewed from an arrow B in FIG.
FIG. 2 is a bottom view of a battery cooler constituting a battery temperature control device having a basic configuration .
FIG. 3 is a view showing a modification of the battery cooler constituting the battery temperature control device of the basic configuration .
FIG. 4 is a view showing another modified example of the battery cooler constituting the battery temperature control device of the basic configuration .
Figure 5 is an overall configuration diagram of a battery-temperature control device of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Battery 2 Distribution means 21 Compressor 22 Condenser 23 Receiver 24a, 24b Expansion valve 3a Battery cooler (battery holding frame)
31,381 Heat transfer substrate (first heat transfer plate)
321, 371, 383 Heat transfer fin (second heat transfer plate)
33 Pipe line 331, 332 Fin tube 333 Turn pipe 3b Evaporator 4 Refrigerant piping 5a, 5b Solenoid valve 6 Case 8 Pressure sensor

Claims (2)

In the battery temperature control device cool the battery, first and heat transfer plate for mounting the battery, and a second heat transfer plate in close contact with the side surface of the upright to the heat transfer plate battery, first A battery holding frame having a pipe line in close contact with the lower surface of the heat transfer plate and made of a heat insulating material and storing the battery holding frame in a state of holding the battery; A distribution means for distributing a heat transport material that exchanges heat with the heat transfer plate through a tube wall;
The battery holding frame has a configuration in which the second heat transfer plate is disposed on the upper surface of the first heat transfer plate so that both are thermally connected. The battery and the second heat transfer plate Alternately arranged and laminated, the second heat transfer plate is brought into close contact with both side surfaces of the battery ,
The distribution means includes a compressor that heats a refrigerant, which is a heat transport material, at a high temperature and a high pressure, a condenser that liquefies the high temperature and pressure refrigerant, and an expansion valve that expands the liquefied refrigerant and lowers the temperature. The pressure detecting means for detecting the pressure in the refrigerant pipe through which the refrigerant flows is provided in the refrigerant pipe located in the sealed case. A battery temperature control device characterized by being installed .   The battery temperature control apparatus of Claim 1 WHEREIN: The battery temperature control apparatus which has arrange | positioned the member which closely_contact | adheres the opposing surface of the said battery and a said 2nd heat exchanger plate.

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