JP7399692B2 - Cooling device and cooling method - Google Patents

Description

The present invention relates to a cooling device and a cooling method for cooling objects to be cooled such as batteries.

Electric vehicles equipped with batteries for driving motors are becoming popular. If the battery is composed of a lithium ion battery, the battery may generate heat during charging and discharging.

Therefore, a technology has been developed that includes a Peltier element and a blower to cool the battery (for example, Patent Document 1).

Japanese Patent Application Publication No. 2013-178977

However, the cooling device including the Peltier element and the blower as described in Patent Document 1 has a problem in that the cost of the device itself and the cost of power consumption are high.

Therefore, there is a desire to develop a technology for cooling objects such as heating elements such as batteries and high-temperature spaces such as greenhouses at low cost.

In view of such problems, an object of the present invention is to provide a cooling device and a cooling method that can cool an object to be cooled at low cost.

In order to solve the above problems, the cooling device of the present invention includes a storage section in which either or both of an aqueous solution of trimethylolethane and trimethylolethane hydrate are accommodated, and an outside air flow formed inside the storage section. an outside air heat exchange section that has an outside air flow path and a lid that communicates with the outside air flow path and exchanges heat between the outside air passing through the outside air flow path and the aqueous solution of trimethylolethane that is accommodated in the storage section; The refrigerant passing through the refrigerant flow path and the trimethylolethane hydrate contained in the storage section and generated by heat exchange of an aqueous solution of trimethylolethane by the outside air heat exchange section. a refrigerant heat exchange unit that exchanges heat with the outside air, an outside air cooling unit that cools the outside air by bringing the outside air in the lid of the outside air heat exchange unit into contact with water, and a refrigerant supply unit that supplies the heat exchanged refrigerant to the object to be cooled. , is provided.

In addition, the cooling device guides the outside air cooled by the outside air cooling section to the outside air heat exchange section when the outside air is at a predetermined threshold temperature or higher, and directs the outside air as it is to the outside air heat exchange section when the outside air is below the threshold temperature. A control unit may be provided to guide the user.

Furthermore, the object to be cooled may be a lithium ion battery unit.

In order to solve the above-mentioned problems, the cooling method of the present invention communicates with an outside air flow path formed in a storage section in which either or both of an aqueous solution of trimethylolethane and trimethylolethane hydrate are accommodated. The outside air in the lid is brought into contact with water to cool the outside air , and the cooled outside air that passes through the outside air flow path is exchanged with the aqueous solution of trimethylolethane stored in the storage section to form trimethylolethane hydride. The refrigerant passing through the refrigerant flow path formed in the storage part and the trimethylol ethane hydrate stored in the storage part are exchanged with each other, and the heat-exchanged refrigerant is supplied to the object to be cooled.

According to the present invention, it is possible to cool an object to be cooled at low cost.

FIG. 1 is a diagram illustrating a schematic configuration of a cooling device according to the present embodiment. FIG. 2 is a diagram illustrating a schematic configuration of a cold storage unit. It is a figure explaining a heat exchange part. FIG. 2 is a diagram illustrating a schematic configuration of a spare unit. It is a flowchart explaining the flow of processing of a cooling method. It is a flow chart explaining the flow of cooling processing. It is a figure explaining the heat exchange part of a modification.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in these embodiments are merely illustrative to facilitate understanding of the invention, and do not limit the invention unless otherwise specified. In this specification and the drawings, elements with substantially the same functions and configurations are given the same reference numerals to omit redundant explanation, and elements not directly related to the present invention are omitted from illustration. do.

[Cooling device 100]
FIG. 1 is a diagram illustrating a schematic configuration of a cooling device 100 according to this embodiment. The cooling device 100 is mounted on, for example, an electric vehicle (EV, such as a taxi). The cooling device 100 cools the object 10 to be cooled. In this embodiment, the object to be cooled 10 is a lithium ion battery unit mounted on an electric vehicle.

As shown in FIG. 1, the cooling device 100 includes a cold storage unit 110, a first refrigerant circulation pipe 120, a refrigerant switching valve 122, a check valve 124, an on-off valve 126, a bypass pipe 130, and a spare unit 150. and a control section 160. Note that in FIG. 1, solid arrows indicate the flow of the first refrigerant. Further, in FIG. 1, broken line arrows indicate the flow of signals.

The cold storage unit 110 cools the first refrigerant (refrigerant). The first refrigerant circulation pipe 120 guides the first refrigerant cooled by the cold storage unit 110 to the cooling target 10 and returns the first refrigerant heated in the cooling target 10 to the cold storage unit 110. That is, the first refrigerant circulation pipe 120 circulates the first refrigerant between the cold storage unit 110 and the object to be cooled 10 .

The refrigerant switching valve 122 is provided between the downstream side of the cold storage unit 110 and the upstream side of the object to be cooled 10 in the first refrigerant circulation pipe 120 . The refrigerant switching valve 122 connects the cold storage unit 110 and the object to be cooled 10, or connects the cold storage unit 110 and the bypass pipe 130.

The check valve 124 is provided between the refrigerant switching valve 122 and the on-off valve 126 in the first refrigerant circulation pipe 120 . The check valve 124 prevents the first refrigerant from flowing back from the object to be cooled 10 to the first refrigerant circulation pipe 120 . The on-off valve 126 is provided between the check valve 124 in the first refrigerant circulation pipe 120 and the object to be cooled 10 .

Bypass pipe 130 connects refrigerant switching valve 122 and between check valve 124 and on-off valve 126 in first refrigerant circulation pipe 120 . The spare unit 150 is provided in the bypass pipe 130.

The control unit 160 is composed of a semiconductor integrated circuit including a CPU (central processing unit). The control unit 160 reads programs, parameters, etc. for operating the CPU itself from a ROM (Read Only Memory). The control unit 160 manages and controls the entire cooling device 100 in cooperation with a RAM (Random Access Memory: readable/writeable memory) as a work area and other electronic circuits. In this embodiment, the control unit 160 controls the cold storage unit 110, the refrigerant switching valve 122, and the reserve unit 150. Specific control processing by the control unit 160 will be detailed later.

In the cooling device 100, the cold storage unit 110 and the reserve unit 150 cool the first refrigerant. The first refrigerant cooled by the cold storage unit 110 or the backup unit 150 is supplied to the object to be cooled 10 through the first refrigerant circulation pipe 120. Therefore, the object to be cooled 10 is cooled by the first refrigerant cooled by the cold storage unit 110 or the reserve unit 150. Then, the first refrigerant whose temperature has increased due to the object to be cooled 10 is returned to the cold storage unit 110 or the reserve unit 150, and is cooled again in the cold storage unit 110 or the reserve unit 150. Note that this embodiment will be described using water as an example of the first refrigerant. Hereinafter, the cold storage unit 110 and the reserve unit 150 will be explained in detail.

[Cold storage unit 110]
FIG. 2 is a diagram illustrating a schematic configuration of the cold storage unit 110. In FIG. 2, solid arrows indicate the flow of the first refrigerant, water, and air.

As shown in FIG. 2, the cold storage unit 110 includes a first refrigerant drum 210, a circulating water pump 220, a heat exchange section 230, and an outside air cooling section 260.

The first refrigerant drum 210 is provided in the first refrigerant circulation pipe 120 and temporarily stores the first refrigerant. Circulating water pump 220 is provided between first refrigerant drum 210 and heat exchange section 230 in first refrigerant circulation pipe 120 . The circulating water pump 220 has a suction side connected to the first refrigerant drum 210, and a discharge side connected to the heat exchange section 230 (refrigerant passage section 250).

The heat exchange unit 230 exchanges heat between trimethylolethane hydrate (hereinafter referred to as "TME hydrate") and the first refrigerant. That is, the heat exchange section 230 functions as a refrigerant heat exchange section. TME hydrate is a hydrate in which trimethylolethane (CH ₃ C(CH ₂ OH) ₃ ) is included as a guest molecule. Further, the heat exchange unit 230 exchanges heat between an aqueous solution of trimethylolethane (hereinafter referred to as "TME aqueous solution") and the outside air. In other words, the heat exchange section 230 also functions as an outside air heat exchange section. Heat exchange section 230 includes a housing section 232, an outside air passage section 240, and a refrigerant passage section 250.

FIG. 3 is a diagram illustrating the heat exchange section 230. FIG. 3A is a schematic diagram of a vertical cross section of the heat exchange section 230. FIG. 3(b) is an XY cross-sectional view of the housing portion 232, the tubes 242 and 252, and the fins 244 and 254. In addition, in the following figures including FIGS. 3(a) and 3(b) of this embodiment, the vertically intersecting X-axis (horizontal direction), Y-axis (horizontal direction), and Z-axis (vertical direction) are Defined as shown. Note that in FIGS. 3(a) and 3(b), the TME aqueous solution and TME hydrate are shown in gray. Furthermore, for ease of understanding, the tubular body 242 and the tubular body 252 are shown to have substantially the same size in FIGS. 3(a) and 3(b).

As shown in FIG. 3(a), the housing portion 232 is a cylindrical heat-insulating container. The accommodating portion 232 is arranged such that the axial direction thereof is the Z-axis direction in FIGS. 3(a) and 3(b). The inner diameter of the accommodating portion 232 is, for example, 340 mm, and the height (length in the Z-axis direction) of the accommodating portion 232 is, for example, 293 mm.

A TME aqueous solution and TME hydrate are accommodated in the accommodation section 232 . In this embodiment, the storage section 232 stores TME hydrate at a mass fraction of 0.600. In other words, the storage section 232 stores a TME aqueous solution containing 0.600 mass fraction of TME. The production temperature (atmospheric pressure) and the decomposition temperature (atmospheric pressure) of TME hydrate with a mass fraction of 0.600 are 30°C. Further, the heat of formation of TME hydrate with a mass fraction of 0.600 is 190 kJ/kg.

The outside air passage section 240 includes one or more pipe bodies 242, a plurality of fins 244, an upper lid 246, and a lower cylinder 248.

The tube body 242 is disposed within the housing portion 232 . The tube body 242 extends in the Z-axis direction in FIGS. 3(a) and 3(b). The upper opening 242a of the tube body 242 faces the internal space of the upper lid 246. The lower opening 242b of the tube body 242 faces the internal space of the lower tube 248.

The fins 244 are provided on the outer peripheral surface of the tube body 242, as shown in FIGS. 3(a) and 3(b). The fins 244 are erected from the outer periphery of the tube body 242 . The fins 244 extend in the Z-axis direction in FIGS. 3(a) and 3(b). In this embodiment, six fins 244 are provided in one tube body 242.

The upper lid 246 has a cylindrical shape and is connected to the upper part of the housing section 232. The upper lid 246 has an opening 246a (air duct) formed at the top. A dustproof net 246b is provided in the opening 246a. In the internal space of the upper lid 246, an outlet manifold 258 of a refrigerant passage section 250, which will be described later, and a spray nozzle 264a of an outside air cooling section 260, which will be described later, are arranged.

The lower cylinder 248 has a cylindrical shape and is connected to the lower part of the housing part 232. The lower cylinder 248 has an opening 248a formed at its lower part. In the internal space of the lower cylinder 248, a drain pan 248b, an inlet manifold 256 of the refrigerant passage section 250, and an air fan 270 of the outside air cooling section 260 are arranged. Drain pan 248b is a perforated drain pan. Air fan 270 is provided below drain pan 248b.

Refrigerant passage section 250 includes one or more tubes 252 , a plurality of fins 254 , an inlet manifold 256 , and an outlet manifold 258 .

The tube body 252 is disposed within the housing portion 232 . The tube body 252 extends in the Z-axis direction in FIGS. 3(a) and 3(b). The tube 252 has a smaller diameter than the tube 242.

The fins 254 are provided on the outer peripheral surface of the tube body 252, as shown in FIGS. 3(a) and 3(b). The fins 254 are erected from the outer periphery of the tube body 252 . The fins 254 extend in the Z-axis direction in FIGS. 3(a) and 3(b). In this embodiment, one tube body 252 is provided with six fins 254.

The inlet manifold 256 connects the lower opening 252b of the pipe body 252 and the first refrigerant circulation pipe 120 (circulating water pump 220 side). The outlet manifold 258 connects the upper opening 252a of the pipe body 252 and the first refrigerant circulation pipe 120 (on the refrigerant switching valve 122 side).

Further, as shown in FIG. 3(b), the tubular body 242 and the tubular body 252 are arranged in the accommodating portion 232 in a houndstooth pattern. Specifically, the plurality of tube bodies 242 can be classified into groups A to C arranged in the Y-axis direction. Each group includes one or more tubes 242. Further, the plurality of tube bodies 252 can be classified into groups DE to E arranged in the Y-axis direction. Each group includes one or more tubes 252. The tubular bodies 242 constituting one group and the tubular bodies 252 constituting a group adjacent to the one group have different positions in the X-axis direction. For example, the tubular bodies 242 constituting group A and the tubular bodies 252 constituting group D are located at different positions in the X-axis direction.

Returning to FIG. 2, the outside air cooling unit 260 cools the outside air by bringing the outside air into contact with water. The outside air cooling unit 260 includes a tank 262 , a water delivery pipe 264 , a spray water pump 266 , a humidity control valve 268 , and an air fan 270 .

Tank 262 stores water. One end of the water delivery pipe 264 is connected to the tank 262, and the other end is provided with a spray nozzle 264a. The spray nozzle 264a is arranged inside the upper lid 246 of the heat exchange section 230. A spray water pump 266 is provided in the water delivery pipe 264. The suction side of the spray water pump 266 is connected to the tank 262, and the discharge side is connected to the spray nozzle 264a. The spray nozzle 264a sprays water. As a result, the outside air inside the upper lid 246 comes into contact with the water, and the outside air is cooled.

The humidity control valve 268 is provided between the spray water pump 266 and the spray nozzle 264a in the water delivery pipe 264. The air fan 270 sucks the air that has passed through the outside air passage section 240 and exhausts it to the outside. Air fan 270 is provided within lower cylinder 248 .

[Spare unit 150]
FIG. 4 is a diagram illustrating a schematic configuration of the spare unit 150. As shown in FIG. 4, reserve unit 150 includes a cooler 310, a refrigerant storage section 320, a flow rate adjustment valve 322, a compressor 330, an air blower section 340, and a condenser 350. Note that in FIG. 4, solid arrows indicate the flow of the first refrigerant. In FIG. 4, the dashed-dotted arrow indicates the flow of the second refrigerant. Further, in FIG. 4, broken line arrows indicate the flow of signals.

Cooler 310 is provided in bypass pipe 130. The cooler 310 exchanges heat between the first refrigerant and the second refrigerant. The cooler 310 cools the first refrigerant with the second refrigerant. Furthermore, the cooler 310 vaporizes the second refrigerant using the heat of the first refrigerant. The second refrigerant is, for example, R-245fa. The check valve 312 is provided upstream of the cooler 310 in the bypass pipe 130.

The refrigerant storage section 320 stores the second refrigerant (liquid). Refrigerant storage section 320 is connected to cooler 310. Flow rate adjustment valve 322 is provided between refrigerant storage section 320 and cooler 310.

Compressor 330 is connected to cooler 310 on its suction side, and connected to condenser 350 on its discharge side. Compressor 330 compresses (boosts the pressure) the second refrigerant.

The blower section 340 blows outside air to the condenser 350. The second refrigerant passing through the condenser 350 is cooled by blowing outside air by the blowing unit 340 . As a result, the latent heat of the second refrigerant is removed in the condenser 350, and the second refrigerant is condensed. The second refrigerant condensed by the condenser 350 is guided to the refrigerant storage section 320.

[Cooling method]
Next, a cooling method using the cooling device 100 will be explained. FIG. 5 is a flowchart illustrating the processing flow of the cooling method. As shown in FIG. 5, the cooling method of this embodiment includes a valve opening process S110, a circulating water pump operation start process S120, a cooling process S200, a stop determination process S130, and a circulating water pump stop process S140. . In this embodiment, the cooling method is started when the electric vehicle in which the object to be cooled 10 is mounted is started. Each process will be explained below.

[Valve opening process S110]
The control unit 160 opens the on-off valve 126 if the on-off valve 126 is closed. Further, if the on-off valve 126 is already opened, the control unit 160 maintains the valve open state. The control unit 160 then controls the refrigerant switching valve 122 to connect the cold storage unit 110 and the object to be cooled 10 .

[Circulating water pump operation start process S120]
The control unit 160 starts the operation of the circulating water pump 220. Thereby, the first refrigerant cooled by the cold storage unit 110 is supplied to the object to be cooled 10 through the first refrigerant circulation pipe 120. That is, the first refrigerant circulation pipe 120 and the circulating water pump 220 function as a refrigerant supply section.

[Cooling process S200]
The control unit 160 performs a cooling process S200. The cooling process S200 will be detailed later.

[Stop determination process S130]
The control unit 160 determines whether the electric vehicle in which the object to be cooled 10 is mounted has stopped and the temperature of the first refrigerant discharged from the object to be cooled 10 is lower than a predetermined deterioration temperature. As a result, if it is determined that the electric vehicle has stopped and the temperature is below the deterioration temperature (YES in S130), the control unit 160 moves the process to circulating water pump stop processing S140. On the other hand, if the control unit 160 determines that the electric vehicle is not stopped or that the first refrigerant is not below the deterioration temperature (NO in S130), the control unit 160 moves the process to cooling process S200 and repeats cooling process S200. Note that the deterioration temperature is the upper limit temperature at which deterioration of the object to be cooled 10 can be suppressed, and is, for example, 32°C.

[Circulating water pump stop processing S140]
The control unit 160 stops the operation of the circulating water pump 220. Further, the control unit 160 stops the spray water pump 266 if the spray water pump 266 is being operated. Note that if the spray water pump 266 has already been stopped, the control unit 160 maintains the stopped state. Further, the control unit 160 stops the compressor 330 if the compressor 330 is being operated. Note that if the compressor 330 has already been stopped, the control unit 160 maintains the stopped state. Moreover, the control unit 160 stops the ventilation unit 340 if the ventilation unit 340 is being operated. Note that if the blower section 340 has already been stopped, the control section 160 maintains the stopped state. Further, the control unit 160 closes the on-off valve 126.

[Cooling process S200]
Next, the cooling process S200 will be explained. FIG. 6 is a flowchart illustrating the flow of cooling process S200. The cooling process S200 includes an outside temperature determination process S200-1, an air fan operation process S200-2, a relative humidity determination process S200-3, an outside air cooling unit operation process S200-4, and a spare unit operation process S200-5. including. Each process will be explained below.

[Outside temperature determination process S200-1]
Control unit 160 determines whether the outside temperature is equal to or higher than a predetermined threshold temperature. As a result, if it is determined that the temperature is equal to or higher than the threshold temperature (YES in S200-1), the control unit 160 moves the process to relative humidity determination process S200-3. On the other hand, if it is determined that the temperature is below the threshold temperature (NO in S200-1), the control unit 160 moves the process to air fan operation process S200-2. Note that the threshold temperature is a temperature at which TME hydrate can be produced, and is, for example, 27.5°C.

[Air fan operation processing S200-2]
If the air fan 270 is stopped, the control unit 160 starts its operation. Further, if the air fan 270 is being operated, the control unit 160 maintains the operation.

Thereby, the air fan 270 sucks outside air through the opening 246a of the upper lid 246 and supplies it to the outside air passage section 240. Then, the outside air passes through the outside air passage section 240, the lower cylinder 248, and the air fan 270, and is exhausted to the outside.

In this way, the outside air passes through the outside air passage section 240 (pipe body 242), thereby exchanging heat between the outside air and the TME aqueous solution. As a result, the TME aqueous solution is cooled by the sensible heat (cold heat) of the outside air, and TME hydrate is generated.

[Relative humidity determination process S200-3]
The control unit 160 determines whether the relative humidity of the outside air is equal to or higher than a predetermined threshold humidity. As a result, if it is determined that the humidity is not higher than the threshold humidity (NO in S200-3), the process moves to outside air cooling unit operation process S200-4. On the other hand, if it is determined that the humidity is equal to or higher than the threshold humidity (YES in S200-3), the control unit 160 moves the process to the spare unit operation process S200-5. Note that the threshold humidity is, for example, 95%.

[Outside air cooling unit operation processing S200-4]
The control unit 160 operates the outside air cooling unit 260. Specifically, if the spray water pump 266 is stopped, the control unit 160 starts the operation of the spray water pump 266. If the spray water pump 266 is in operation, the control unit 160 maintains its operation. Furthermore, if the air fan 270 is stopped, the control unit 160 causes the air fan 270 to start operating. If the air fan 270 is being operated, the control unit 160 maintains the operation. Further, the control unit 160 adjusts the opening degree of the humidity control valve 268 so that the relative humidity becomes less than the threshold humidity.

Thereby, water is sprayed in a mist form from the spray nozzle 264a, and the outside temperature inside the upper lid 246 can be lowered by the latent heat of vaporization of the water. In other words, it is possible to lower the temperature of the outside air passing through the outside air passage section 240 to below the threshold temperature. Note that when the outside temperature is 37° C., the amount of spray water required to lower the outside air to below the threshold temperature is about 1.2 kg/h.

[Spare unit operation processing S200-5]
The control unit 160 controls the refrigerant switching valve 122 to connect the reserve unit 150 and the object to be cooled 10 . The control unit 160 then operates the reserve unit 150. Specifically, if the compressor 330 is stopped, the control unit 160 starts the operation of the compressor 330. If the compressor 330 is being operated, the control unit 160 maintains the operation. Furthermore, if the blower 340 is stopped, the controller 160 causes the blower 340 to start operating. If the blower unit 340 is being operated, the control unit 160 maintains the operation.

As explained above, the cooling device 100 of this embodiment and the cooling method using the same cool the object to be cooled 10 with the heat of decomposition (endotherm) of TME hydrate.

A lithium ion battery unit as the object to be cooled 10 is used as a power source for an electric vehicle. Even when a lithium ion battery unit is discharging (while an electric vehicle is running), when about two-thirds or more of the battery capacity is consumed, heat dissipation from the lithium ion battery increases rapidly. The amount of heat released from the lithium ion battery when 2/3 of the battery capacity is consumed corresponds to about 0.7% of the power used. For example, when the electric vehicle is a taxi, the amount of heat dissipated increases by about 0.22 kW (The Japan Society Calorimetry and Thermal Analysis. Netsu Sokutei 30(1) 2003). When the temperature of the lithium ion battery unit exceeds 35° C., the deterioration of the lithium ion battery unit progresses (for example, Society of Automotive Engineers of Japan Proceedings Vol. 47, No. 1, January 2016).

Therefore, the cooling device 100 cools the object to be cooled 10 using the decomposition heat of TME hydrate. As described above, in this embodiment, the heat of decomposition of TME hydrate is 30°C. Therefore, even during periods when the outside temperature is high, such as in summer, the cooling device 100 can keep the first refrigerant at a temperature of less than 30° C., and cools the lithium ion battery unit (cooling target 10) with the first refrigerant. It becomes possible to do so. Thereby, the lithium ion battery unit can be maintained at a temperature below 35° C., and deterioration of the lithium ion battery unit can be suppressed. Therefore, in the electric vehicle, the frequency of replacing the lithium ion battery unit can be reduced. This makes it possible to reduce the cost required to replace a lithium ion battery unit in an electric vehicle. Furthermore, the cooling device 100 can reduce the power consumption of the cooling mechanism that constitutes the lithium ion battery unit, making it possible to extend the traveling distance of the electric vehicle.

Moreover, when the case where the cold storage unit 110 is operated to cool the lithium ion battery unit (cooling target 10) and the case where the lithium ion battery unit is cooled by the reserve unit 150 are compared, the case where the cold storage unit 110 is operated in the cooling mode is compared. However, the COP (Coefficient Of Performance) and power consumption are lower. Specifically, the COP when the cold storage unit 110 is operated in the cooling mode to cool the lithium ion battery unit is 1.4 times that when the reserve unit 150 is used to cool the lithium ion battery unit. Further, the power consumption when the cold storage unit 110 is operated in the cooling mode to cool the lithium ion battery unit is 0.28 times that when the reserve unit 150 is used to cool the lithium ion battery unit. In other words, compared to a conventional cooling device using a condensed refrigerant such as R-245fa, or a conventional cooling device equipped with an air blower and a Peltier element, the cooling device 100 of this embodiment can cool the object 10 at a lower cost. Can be cooled.

Furthermore, the configuration including the outside air cooling unit 260 allows the cooling device 100 to generate TME hydrate even when the outside temperature exceeds the threshold temperature. In addition, in most areas of Japan, the outside temperature in summer is 30°C or higher. However, in most areas of Japan, the wet bulb temperature (saturation temperature) is 27° C. or lower even if the outside temperature is high. Therefore, it becomes possible to lower the outside air supplied to the outside air passage section 240 by the outside air cooling section 260 to below the threshold temperature.

Further, as described above, the first refrigerant (water) flows within the tube body 252 from the lower opening 252b toward the upper opening 252a. The specific gravity of TME hydrate is 1.11. On the other hand, the specific gravity of the TME aqueous solution produced by the decomposition of TME hydrate is 1.003. In other words, the TME aqueous solution is lighter than the TME hydrate (specific gravity difference: 0.107). Therefore, by circulating the first refrigerant from the lower part of the pipe body 252 toward the upper part, TME hydrate can be decomposed from the lower part of the storage section 232.

As a result, the TME aqueous solution dissolved by exchanging heat with the first refrigerant (water) rises within the storage portion 232 (becomes an upward flow). Since the upward flow of the TME aqueous solution collapses the TME hydrate layer, it is possible to improve the frequency of contact between the TME hydrate and the tube body 252. Thereby, the heat exchange section 230 can efficiently cool the first refrigerant within the tube body 252. Furthermore, convection occurs when the TME hydrate layer collapses, resulting in convective heat transfer. Thereby, the heat exchange section 230 can efficiently cool the first refrigerant within the tube body 252.

Further, as described above, the refrigerant passage section 250 that constitutes the heat exchange section 230 includes fins 254 on the outer periphery of the tube body 252. Thereby, the heat exchange section 230 can improve the heat exchange efficiency between the first refrigerant (water) and TME hydrate.

On the other hand, as described above, outside air flows within the tube body 242 from the upper opening 242a toward the lower opening 242b. Therefore, by circulating outside air from the upper part of the tube body 242 toward the lower part, TME hydrate can be generated from the upper part of the storage part 232. The generated TME hydrate descends within the storage section 232 (becomes a downward flow). This causes convection within the housing portion 232, resulting in convective heat transfer. Therefore, the heat exchange unit 230 can efficiently exchange heat between the outside air inside the tube body 242 and the TME aqueous solution.

Further, with the above configuration, the TME hydrate can be dropped, that is, the TME hydrate can be removed from the upper part of the storage section 232, which is in contact with the coldest outside air. Thereby, the heat exchange section 230 can suppress inhibition of heat transfer from the TME aqueous solution to the outside air, and can efficiently generate TME hydrate.

Furthermore, the air fan 270 has its suction side connected to the lower cylinder 248 (lower opening 242b). Thereby, it is possible to avoid a situation where outside air heated by the air fan 270 is supplied to the heat exchange section 230. Therefore, the heat exchange section 230 can efficiently generate TME hydrate.

Further, as described above, the outside air passage section 240 that constitutes the heat exchange section 230 includes fins 244 on the outer periphery of the tube body 242. Thereby, the heat exchange section 230 can improve the heat exchange efficiency between the outside air and the TME aqueous solution. Furthermore, the fins 244 can smooth the flow of the TME aqueous solution within the storage section 232.

Furthermore, by including the drain pan 248b, the heat exchange section 230 can avoid a situation in which water sprayed from the spray nozzle 264a is introduced into the air fan 270. Thereby, the drain pan 248b can suppress malfunctions of the air fan 270.

The cooling device 100 also includes a spare unit 150. As mentioned above, in most regions of Japan, the saturation temperature of the outside air is 27° C. or lower, so the backup unit 150 is rarely operated. However, in areas where the outside air saturation temperature is always 27°C or higher, or when the outside air saturation temperature is 27°C or higher all day long due to abnormal weather, it is possible to generate TME hydrate by operating the backup unit 150. can.

[Modified example]
In the above embodiment, the configuration in which the heat exchange section 230 includes the housing section 232 and the tube bodies 242 and 252 has been described as an example. However, there is no limitation on the shape of the heat exchange section. The heat exchange section may be configured with a plate heat exchanger, for example.

FIG. 7 is a diagram illustrating a heat exchange section 410 of a modified example. FIG. 7A is an exploded perspective view of the heat exchange section 410. FIG. 7B is a plan view showing the front surface 420a of the first plate 420. FIG. 7C is a plan view showing the front surface 430a of the second plate 430. FIG. 7D is a plan view showing the front surface 440a of the third plate 440. FIG. 7E is a plan view showing the rear surface 420b of the first plate 420, the rear surface 430b of the second plate 430, and the rear surface 440b of the third plate 440. Note that in FIG. 7A, the first plate 420, the second plate 430, and the third plate 440 are shown smaller than they actually are in order to facilitate understanding. Further, in FIG. 7(a), solid arrows indicate the flow of the first refrigerant. Furthermore, for ease of understanding, the upper lid 246 and lower cylinder 248 are omitted.

As shown in FIG. 7A, the heat exchange section 410 includes a plurality of first plates 420, a plurality of second plates 430, a plurality of third plates 440, a sealing plate 450, and an entrance/exit plate 460. Contains. The first plate 420, the second plate 430, the third plate 440, the sealing plate 450, and the entrance/exit plate 460 are made of a material with high thermal conductivity such as metal. Specifically, the heat exchanger 410 includes a first plate 420, a second plate 430, a third plate 440, a second plate 430, and a first plate 420 between the sealing plate 450 and the entrance/exit plate 460. It is constructed by stacking layers in order. That is, in the heat exchange section 410, the first plate 420 and the third plate 440 are arranged alternately between the sealing plate 450 and the entrance/exit plate 460, and the first plate 420 and the third plate 440 are arranged alternately. A second plate 430 is arranged between them.

The first plate 420 is a substantially rectangular flat plate, as shown in FIG. 7(b). The first plate 420 is formed with two through holes 422a and 422b that penetrate from the front surface 420a to the rear surface 420b. The through hole 422a is formed in the upper part of the first plate 420, and the through hole 422b is formed in the lower part of the first plate 420. The through hole 422b is formed vertically below the through hole 422a. Further, the front surface 420a of the first plate 420 is provided with a protrusion 424 that protrudes in the −Y-axis direction in FIGS. 7(a) and 7(b). The protrusion 424 is provided at the outer edge of the first plate 420 . A groove 426 depressed in the +Y-axis direction is formed inside the protrusion 424 in FIGS. 7(a) and 7(b). That is, through holes 422a and 422b are formed in the groove portion 426.

The second plate 430 is a substantially rectangular flat plate, as shown in FIG. 7(c). Two through holes 432a and 432b are formed in the second plate 430, penetrating from the front surface 430a to the rear surface 430b. The through hole 432a is formed in the upper part of the second plate 430, and the through hole 432b is formed in the lower part of the second plate 430. The through hole 432b is formed vertically below the through hole 432a. Further, the front surface 430a of the second plate 430 is provided with a protrusion 434 that protrudes in the −Y-axis direction in FIGS. 7(a) and 7(c). The protrusion 434 surrounds and partitions a region of the front surface 430a of the second plate 430 where the through hole 432a is formed and a region where the through hole 432b is formed. Grooves 436a and 436b depressed in the +Y-axis direction in FIGS. 7A and 7C are formed inside the protrusion 434. As shown in FIGS.

The third plate 440 is a substantially rectangular flat plate, as shown in FIG. 7(d). The third plate 440 is formed with two through holes 442a and 442b that penetrate from the front surface 440a to the rear surface 440b. The through hole 442a is formed in the upper part of the third plate 440, and the through hole 442b is formed in the lower part of the third plate 440. The through hole 442b is formed vertically below the through hole 442a. Furthermore, a flange 444a is provided on the front surface 440a of the third plate 440, surrounding the through hole 442a and protruding in the −Y-axis direction in FIGS. 7(a) and 7(d). Similarly, the front surface 440a of the third plate 440 is provided with a flange 444b that surrounds the through hole 442b and protrudes in the −Y-axis direction in FIGS. 7(a) and 7(d).

Further, as shown in FIG. 7(e), the rear surface 420b of the first plate 420, the rear surface 430b of the second plate 430, and the rear surface 440b of the third plate 440 are aligned along the XZ plane in FIG. 7(e). It has a flat planar shape.

Returning to FIG. 7A, the sealing plate 450 is a flat plate having substantially the same shape and size as the first plate 420, the second plate 430, and the third plate 440. No through holes are formed in the sealing plate 450.

The entry/exit plate 460 is a flat plate having substantially the same shape and size as the first plate 420, the second plate 430, and the third plate 440. The entrance/exit plate 460 is formed with an upper opening 462a and a lower opening 462b. When connected to the second plate 430, the upper opening 462a is formed in the entrance/exit plate 460 so as to communicate with the through hole 432a, and the lower opening 462b communicates with the through hole 432b. Note that the heat exchange section 410 is installed such that the lower opening 462b is located below the upper opening 462a.

As shown in FIG. 7A, a rear surface 430b of a second plate 430 is connected to a front surface 420a of the first plate 420 (for example, by brazing). Specifically, the protrusion 424 of the first plate 420 is connected to the rear surface 430b of the second plate 430. Further, the front surface 430a of the second plate 430 is connected to the rear surface 440b of the third plate 440. Specifically, the protrusion 434 of the second plate 430 is connected to the rear surface 440b of the third plate 440. Further, the rear surface 430b of the second plate 430 is connected to the front surface 440a of the third plate 440. Specifically, the flanges 444a and 444b of the third plate 440 are connected to the rear surface 430b of the second plate 430. In this way, a stacked body is formed in which the first plate 420, the second plate 430, the third plate 440, and the second plate 430 are stacked in this order. A sealing plate 450 is connected to the rear surface 420b of the first plate 420 located at one end of the stack. Furthermore, the rear surface of the access plate 460 is connected to the front surface 430a (protrusion 434) of the second plate 430 located at the other end of the stack.

In this way, by stacking the first plate 420, the second plate 430, the third plate 440, the sealing plate 450, and the entrance/exit plate 460, the upper opening 462a, the through hole 422a, the through hole 442a, and the through hole 432a are formed. A flow path 412 is formed. That is, the flow path 412 is a flow path in which an upper opening 462a is formed at one end and the other end is sealed by the sealing plate 450. Further, a flow path 414 is formed by the lower opening 462b, the through hole 422b, the through hole 442b, and the through hole 432b. In other words, the flow path 414 is a flow path in which the lower opening 462b is formed at one end and the other end is sealed by the sealing plate 450. Note that the flow path 412 and the flow path 414 extend in the horizontal direction. Further, the flow path 412 and the flow path 414 are communicated with each other through the groove portion 436a.

Furthermore, TME hydrate and a TME aqueous solution are accommodated in a groove 436b between the front surface 430a of the second plate 430 and the rear surface 420b of the first plate 420, in which the through holes 432a and 432b are not formed. That is, the groove 436b between the front surface 430a of the second plate 430 and the rear surface 420b of the first plate 420 functions as a housing section.

Similarly, TME hydrate and TME aqueous solution are accommodated in a groove 436b between the front surface 430a of the second plate 430 and the rear surface 440b of the third plate 440, in which the through holes 432a and 432b are not formed. That is, the groove 436 between the front surface 430a of the second plate 430 and the rear surface 440b of the third plate 440 functions as a housing section.

Further, a gap is formed between the front surface 440a of the third plate 440 and the rear surface 430b of the second plate 430. This gap corresponds to the outside air passage section 240 that constitutes the heat exchange section 230 of the above embodiment.

The first refrigerant circulation pipe 120 is connected to the upper opening 462a and the lower opening 462b.

Therefore, as shown in FIG. 7A, the first refrigerant is introduced from the lower opening 462b, and the flow path 414 (through hole 422b, through hole 432b, through hole 442b) is As it passes in the direction, it ascends through the groove portion 426. The first refrigerant that has ascended through the groove portion 426 passes through the flow path 412 (through-hole 422a, through-hole 432a, through-hole 442b) in the −Y-axis direction in FIG. 7(a), and is discharged from the upper opening 462a.

In the heat exchange section 410, heat is exchanged between the first refrigerant flowing upward in the groove 426 and the TME hydrate accommodated in the groove 436b. Specifically, the groove 426 and the groove 436b are separated by the first plate 420 or the second plate 430. That is, the groove part 426 and the groove part 436b are provided so that heat can be transferred by the first plate 420 or the second plate 430. Therefore, heat exchange occurs between the first refrigerant flowing through the groove 426 and the TME hydrate accommodated in the groove 436b. In this way, TME hydrate is decomposed in the groove portion 436b.

Further, the upper lid 246 is connected to the upper part of the stacked body, and the lower cylinder 248 is connected to the lower part of the stacked body. Therefore, the outside air introduced from the upper lid 246 passes through the gap formed in the laminate (between the front surface 440a of the third plate 440 and the rear surface 430b of the second plate 430) from above to below. The outside air that has descended through the stack passes through the lower tube 248 and is then discharged.

Then, in the heat exchange section 410, heat exchange is performed between the outside air flowing downward through the gap and the TME aqueous solution accommodated in the groove section 436b. In this way, TME hydrate is generated in the groove portion 436b.

Although preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to these embodiments. It is clear that those skilled in the art can come up with various changes and modifications within the scope of the claims, and it is understood that these naturally fall within the technical scope of the present invention. be done.

For example, in the above embodiment, the case where the cooling device 100 is mounted on an electric vehicle has been described as an example. However, the cooling device 100 may be installed at a charging stand for an electric vehicle.

Furthermore, in the above embodiment, water was used as an example of the first refrigerant. However, the first refrigerant is not limited. For example, a substance that condenses when cooled by TME hydrate or air may be used as the first refrigerant.

Furthermore, in the above embodiment, the case where the tubular body 252 has a smaller diameter than the tubular body 242 has been described as an example. However, the diameter of the tube body 252 is not limited. For example, tube 252 may have substantially the same diameter as tube 242, or may have a larger diameter than tube 242.

Further, in the above embodiment, the configuration in which the first refrigerant flows from the lower opening 252b toward the upper opening 252a has been described as an example. However, the first refrigerant may be configured to flow from the upper opening 252a toward the lower opening 252b.

Furthermore, in the above embodiment, the configuration in which the tube bodies 242 and 252 extend in the vertical direction has been described as an example. However, there is no limitation on the extending direction of the tubes 242, 252. Tube 242 or tube 252 may extend horizontally, for example.

Further, in the above embodiment, the cooling device 100 has been described using an example of a configuration including one cold storage unit 110. However, the cooling device 100 may include two or more cold storage units 110.

Furthermore, in the above embodiment, a lithium ion battery unit has been described as an example of the object to be cooled 10. However, the cooling target 10 is not limited. For example, the object to be cooled 10 may be a heating element other than a lithium ion battery unit, or a high temperature space such as a greenhouse.

Further, in the above embodiment, TME hydrate with a mass fraction of 0.600 was used as an example. However, there is no limit to the amount of TME in TME hydrate.

Further, in the above embodiment, TME hydrate was used as an example. However, the hydrate guest molecules are not limited to TME. The guest molecules of the hydrate can be appropriately set depending on the outside temperature. For example, when the cooling device 100 is installed in a season when the outside temperature is low or in a region where the outside temperature is low, a hydrate having a decomposition temperature (atmospheric pressure) of less than 30° C. may be used. For example, the cooling device 100 may employ ionic semiclathrate containing freon, chlorine, acrylate, or the like as a guest molecule. Thereby, the cooling device 100 can cool the object to be cooled 10 more efficiently.

INDUSTRIAL APPLICATION This invention can be utilized for a cooling device and a cooling method.

100 Cooling device 120 First refrigerant circulation pipe (refrigerant supply section)
160 Control unit 220 Circulating water pump (refrigerant supply unit)
230 Heat exchange section (outside air heat exchange section, refrigerant heat exchange section)
260 Outside air cooling section

Claims (4)

a storage section in which one or both of an aqueous solution of trimethylolethane and trimethylolethane hydrate are accommodated;
It has an outside air flow path formed in the storage section and a lid communicating with the outside air flow path, and heats the outside air passing through the outside air flow path and the aqueous solution of trimethylolethane stored in the storage section. an outside air heat exchanger for exchanging;
It has a refrigerant flow path formed in the storage part, and heat exchanges between the refrigerant passing through the refrigerant flow path and the aqueous solution of trimethylolethane stored in the storage part and by the outside air heat exchange part. a refrigerant heat exchange unit that exchanges heat with the generated trimethylolethane hydrate;
an outside air cooling unit that cools the outside air by bringing the outside air in the lid of the outside air heat exchange unit into contact with water;
a refrigerant supply unit that supplies the heat-exchanged refrigerant to a cooling target;
A cooling device equipped with. When the outside air is above a predetermined threshold temperature, the outside air cooled by the outside air cooling section is guided to the outside air heat exchange section, and when the outside air is below the threshold temperature, the outside air is guided as it is to the outside air heat exchange section. The cooling device according to claim 1, further comprising a control section. The cooling device according to claim 1 or 2, wherein the object to be cooled is a lithium ion battery unit. Cooling the outside air by bringing water into contact with the outside air in a lid that communicates with an outside air flow path formed in a storage section in which either or both of an aqueous solution of trimethylolethane and trimethylolethane hydrate are accommodated. death,
generating trimethylolethane hydrate by exchanging heat between the cooled outside air passing through the outside air flow path and an aqueous solution of trimethylolethane accommodated in the storage section ;
exchanging heat between a refrigerant passing through a refrigerant flow path formed in the storage part and the trimethylol ethane hydrate contained in the storage part ,
A cooling method in which the heat-exchanged refrigerant is supplied to an object to be cooled.

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