WO2019093065A1

WO2019093065A1 - Evaporator

Info

Publication number: WO2019093065A1
Application number: PCT/JP2018/037945
Authority: WO
Inventors: 康光大見; 功嗣三浦; 義則　毅
Original assignee: 株式会社デンソー
Priority date: 2017-11-09
Filing date: 2018-10-11
Publication date: 2019-05-16
Also published as: JP6919511B2; JP2019086254A

Abstract

Provided is an evaporator applied to a thermosyphon type cooling device. The inside of a flat multi-hole tube (21) forming an evaporation section for evaporating an operating fluid is divided into first to fifth fluid passages (211a-211e) through which the operating fluid flows upward from below. The openings of first to fifth inlets (212a-212e) of the fluid passages are arranged at vertically different positions. A plurality of such flat multi-hole tubes are arranged next to each other in the longitudinal direction of a liquid supply tank (22), and the first inlets open at the lowermost ends are arranged at a certain distance from the evaporation section. As a result, even if a gas-phase operating fluid enters the liquid supply tank, a liquid-phase operating fluid can be uniformly distributed to the entire region of the liquid supply tank, and the entire battery pack (BP) can be uniformly cooled.

Description

Evaporator

Cross-reference to related applications

This application is based on Japanese Patent Application No. 2017-216528 filed on Nov. 9, 2017, the disclosure of which is incorporated by reference into the present application.

The present disclosure relates to an evaporator that is applied to a thermosiphon-type cooling device to evaporate a working fluid.

Conventionally, a thermo-siphon type cooling device is known. This type of thermosiphon-type cooling device includes an evaporator for evaporating a liquid phase working fluid and a condenser for condensing a vapor phase working fluid evaporated by the evaporator. Then, the heat of the object to be cooled is absorbed by the working fluid in the evaporator to cool the object to be cooled. Further, in the condenser, the heat absorbed by the working fluid from the object to be cooled is dissipated to the outside.

Further, the condenser is disposed on the upper side of the evaporator so that the working fluid in the liquid phase, which is denser than the working fluid in the gaseous phase, flows from the condenser to the evaporator by the action of gravity. Thereby, the working fluid is naturally circulated to enable continuous cooling of the object to be cooled.

For example, Patent Document 1 discloses a thermosiphon-type cooling device used for cooling a battery assembly formed by stacking a plurality of battery cells.

The cooling device of Patent Document 1 includes an evaporator provided with a fluid passage in contact with the side surface of the assembled battery and extending in the stacking direction of the battery cells. In the evaporator of Patent Document 1, the working fluid in the liquid phase is allowed to flow in from the fluid inlet provided at one longitudinal end side of the fluid passage. Then, when flowing through the fluid passage, the gas phase working fluid which has absorbed heat and evaporated from the assembled battery is made to flow out from the fluid outlet provided on the other end side in the longitudinal direction of the fluid passage.

Patent No. 5942943 gazette

By the way, as in Patent Document 1, in the evaporator having a fluid passage extending in the stacking direction of the battery cells, the battery cells can be sufficiently cooled by the latent heat of vaporization of the working fluid at a location where there is a large amount of working fluid in liquid phase. it can. However, since it is not possible to evaporate the working fluid at a portion of the fluid passage where the working fluid in the gas phase is unevenly distributed, so-called dry out that cooling of the battery cell in contact with the portion becomes insufficient. It can occur.

Furthermore, in a battery pack formed by stacking a plurality of battery cells, if the cooling of any battery cell is insufficient and the performance of the battery cell is degraded, the overall performance of the battery pack is degraded. Resulting in. For this reason, in a cooling object such as a battery pack, it is desirable that the entire cooling object be cooled uniformly.

The present disclosure is an evaporator applied to a thermosiphon-type cooling device, and an object of the present disclosure is to provide an evaporator that can uniformly cool the entire object to be cooled.

According to one aspect of the present disclosure, it is an evaporator applied to a thermosiphon cooling device. The evaporator comprises a working fluid tube for circulating the working fluid, and a liquid supply unit connected to the lower end of the working fluid tube to distribute the working fluid in the liquid phase to the working fluid tube. The working fluid tube forms an evaporation unit that evaporates the working fluid by absorbing the heat of the object to be cooled by the liquid phase working fluid flowing therethrough. The inside of the working fluid tube is divided into a plurality of fluid passages for passing the working fluid from the lower side to the upper side. In the inlets of the plurality of fluid passages, at least a part of the inlets is opened inside the liquid supply unit, and the opening positions of the respective inlets are different in the vertical direction.

According to this, the opening positions of at least a part of the inlets of the plurality of fluid passages through which the working fluid flows from the lower side to the upper side are different in the vertical direction. For this reason, the working fluid in the liquid phase in the liquid supply portion is easily supplied to the fluid passage in which the inlet portion is opened at the lower side among the plurality of fluid passages.

Therefore, by arranging the fluid passage to which the working fluid in the liquid phase is likely to be supplied spaced apart from the working fluid tube forming the evaporating unit, the working fluid in the liquid phase can be supplied from the liquid supply unit to the entire region of the evaporating unit. It can be distributed almost evenly. As a result, the whole of the object to be cooled can be uniformly cooled by the latent heat of evaporation of the working fluid in the entire area of the evaporation section.

It is a block diagram of the thermosiphon type cooling device of 1st Embodiment. It is a disassembled perspective view of the evaporator of 1st Embodiment. It is a schematic cross section which shows the inside of the liquid supply tank of the evaporator of 1st Embodiment. It is explanatory drawing which shows the arrangement | positioning relationship between the evaporator of 1st Embodiment, and an assembled battery. It is a schematic cross section which shows the inside of the liquid supply tank of the evaporator of 2nd Embodiment. It is a disassembled perspective view of the evaporator of 3rd Embodiment. It is a schematic cross section which shows the inside of the liquid supply tank of the evaporator of 3rd Embodiment. It is a schematic cross section which shows the inside of the liquid supply tank of the evaporator of 4th Embodiment. It is a disassembled perspective view of the evaporator of 5th Embodiment. It is a typical enlarged view of the X section of 5th Embodiment. It is a typical enlarged view corresponding to FIG. 10 of the modification of 5th Embodiment. FIG. 21 is a schematic enlarged view corresponding to FIG. 10 of another modified example of the fifth embodiment. It is a schematic cross section which shows the inside of the liquid supply tank of the evaporator of 6th Embodiment. It is XIV-XIV sectional drawing of FIG. It is a disassembled perspective view of the evaporator of other embodiment.

Hereinafter, a plurality of modes for carrying out the present disclosure will be described with reference to the drawings. The same referential mark may be attached | subjected to the part corresponding to the matter demonstrated by the form preceded in each form, and the overlapping description may be abbreviate | omitted. When only a part of the configuration is described in each form, the other forms described above can be applied to other parts of the configuration. Not only combinations of parts which clearly indicate that combinations are possible in each embodiment, but also combinations of embodiments even if they are not specified unless there is a problem with the combination. Is also possible.

First Embodiment
A first embodiment of the present disclosure will be described using FIGS. 1 to 4. In the present embodiment, the thermosiphon cooling device 1 to which the evaporator 2 according to the present disclosure is applied is used to cool the battery pack BP mounted on the electric vehicle. Therefore, the thermosiphon cooling device 1 is mounted on the vehicle together with the battery pack BP. Furthermore, the object to be cooled in the evaporator 2 is the battery pack BP.

In the electric vehicle, the battery pack BP has a function of storing electric power and a function of supplying the stored electric power to on-vehicle equipment such as a traveling electric motor. The battery pack BP is obtained by electrically connecting a plurality of battery cells BC in series. The battery cell BC is a chargeable / dischargeable secondary battery (for example, a lithium ion battery, a lead storage battery).

This type of battery cell BC involves heat generation during charge and discharge. Furthermore, the battery cell BC is likely to be deteriorated due to temperature rise due to self-heating or the like. For this reason, it is desirable that each battery cell BC be cooled so as not to exceed a predetermined reference temperature. That is, it is desirable that the entire assembled battery BP be uniformly cooled so that all the battery cells BC are cooled.

Each battery cell BC is formed in a substantially rectangular parallelepiped shape. The assembled battery BP is formed by stacking the battery cells BC in two rows in a predetermined direction. For this reason, the external shape of the battery pack BP is also substantially rectangular.

Next, the thermosiphon cooling device 1 will be described. As shown in FIG. 1, the thermosiphon cooling device 1 includes an evaporator 2, a gas phase fluid pipe 3, a condenser 4, and a liquid phase fluid pipe 5. The thermosiphon cooling device 1 is configured by connecting these components in an annular manner (ie, in a closed loop).

The evaporator 2 absorbs the heat of the battery pack BP to the working fluid in the liquid phase to evaporate the working fluid. In this embodiment, a fluorocarbon-based refrigerant (specifically, R134a) used in a vapor compression refrigeration cycle is employed as the working fluid. The detailed configuration of the evaporator 2 will be described later.

A gas phase fluid pipe 3 is connected to the fluid outlet 23 a of the evaporator 2. The gas phase fluid piping 3 is a fluid piping that leads the gas phase working fluid evaporated in the evaporator 2 to the fluid inlet of the condenser 4. The gas phase fluid piping 3 is preferably a piping having a passage cross-sectional area larger than that of the liquid phase fluid piping 5 in order to reduce the pressure loss that occurs when the working fluid in the gas phase flows.

The condenser 4 dissipates heat and condenses the working fluid of the gas phase which has flowed in via the gas phase fluid piping 3. In the present embodiment, a heat exchanger for exchanging heat between the gas phase working fluid and the low pressure refrigerant of the vapor compression refrigeration cycle is adopted as the condenser 4. The condenser 4 is disposed above the evaporator 2.

A liquid phase fluid pipe 5 is connected to the fluid outlet of the condenser 4. The liquid-phase fluid piping 5 is a fluid piping that leads the working fluid of the liquid phase condensed by the condenser 4 to the fluid inlet 22 a of the evaporator 2.

Next, the detailed configuration of the evaporator 2 will be described using FIGS. 2 to 4. In addition, each arrow of the upper and lower sides in each drawing has shown each direction of the upper and lower sides in the state which mounted the thermosiphon type cooling device 1 in the vehicle. Further, in each drawing, a part of battery cells BC forming the assembled battery BP is drawn by a two-dot chain line for the sake of clarification of the illustration.

The evaporator 2 includes a plurality of flat multi-hole tubes 21, a liquid supply tank 22, and a fluid outflow tank 23.

The plurality of flat multi-hole tubes 21 form an evaporation unit that evaporates the working fluid by absorbing the heat of the battery pack BP by the working fluid in the liquid phase flowing therethrough. Each flat multi hole tube 21 is a working fluid tube which forms a refrigerant passage which distributes a working fluid. The flat multi-hole tube 21 is formed of a metal (in the present embodiment, an aluminum alloy) which is excellent in heat conductivity.

The flat multi-hole tube 21 is formed to have a flat cross-sectional shape perpendicular to the longitudinal direction. Here, the flat shape in the present embodiment is a shape in which the ends of two parallel line segments are connected by a curve or a straight line, and the thickness dimension which is the distance between the two line segments is two. It can be defined as a horizontally elongated shape which is shorter than the width dimension of the direction in which the line segment extends (hereinafter referred to as the width direction). Furthermore, the part which becomes two line segments parallel in cross-sectional shape is a part which forms the flat surface (henceforth flat surface) of the back and front of flat multi hole tube 21.

The flat multi-hole tube 21 is formed with a plurality of through holes extending in the longitudinal direction. These through holes are arranged in a line in the width direction. For this reason, the inside of the flat multi-hole tube 21 is divided by the plurality of through holes into a plurality of fluid passages for circulating the working fluid.

As shown in FIG. 3, the inside of the flat multi-hole tube 21 of the present embodiment is a first fluid passage 211a, a second fluid passage 211b, a third fluid passage 211c, a fourth fluid passage 211d, and a fifth fluid passage 211e ( Hereinafter, it is divided into five fluid passages of “first fluid passage 211 a to fifth fluid passage 211 e”. The flat multi-hole tube 21 is disposed such that the longitudinal direction is the vertical direction. Therefore, in the first fluid passage 211a to the fifth fluid passage 211e of the present embodiment, the working fluid is circulated in parallel from the lower side to the upper side.

The lower end of the flat multi-hole tube 21 has a first inlet 212a, a second inlet 212b, and a third inlet 212c, which allow the working fluid to flow into the first fluid passage 211a to the fifth fluid passage 211e, respectively. A fourth inlet 212d and a fifth inlet 212e (hereinafter, referred to as "first inlet 212a to fifth inlet 212e") are formed. The first inlet portion 212 a to the fifth inlet portion 212 e are opened inside the liquid supply tank 22.

Furthermore, as shown in FIG. 3, the lower end surface of the flat multi-hole tube 21 is inclined with respect to the horizontal plane. For this reason, the opening positions of the first inlet portion 212a to the fifth inlet portion 212e are different in the vertical direction.

In the present embodiment, the opening positions of the first inlet portion 212 a to the fifth inlet portion 212 e are sequentially changed in the width direction of the flat multi-hole tube 21. That is, as shown in FIG. 3, from the right side to the left side as viewed in the drawing, the opening positions are in the order of first inlet 212a → second inlet 212b → third inlet 212c → fourth inlet 212d → fifth inlet 212e. Is high. Therefore, the first inlet 212a is a bottom inlet which is opened at a position closest to the bottom of the liquid supply tank 22 among the first inlet 212a to the fifth inlet 212e.

Such a flat multi-hole tube 21 can be manufactured by forming a plurality of through holes in one metal member by extrusion molding or the like and cutting its end obliquely with respect to the longitudinal direction.

The liquid supply tank 22 is a liquid supply unit that distributes and supplies a working fluid of a liquid phase to each fluid passage of the flat multi-hole tube 21. The liquid supply tank 22 is formed of a metal similar to the flat multi-hole tube 21 and has a bottomed cylindrical shape extending in the horizontal direction. At one end in the longitudinal direction of the liquid supply tank 22, a fluid inflow port 22a is provided to which the working fluid of the liquid phase condensed by the condenser 4 flows.

On the side surface of the liquid supply tank 22, a plurality of insertion holes 22b to which the lower end of the flat multi-hole tube 21 is inserted and connected are formed. The insertion holes 22 b of the liquid supply tank 22 are formed in a line in the longitudinal direction of the liquid supply tank 22 so that the flat surfaces on both sides of the flat multi-hole tube 21 are arranged on the same plane.

Therefore, the plurality of flat multi-hole tubes 21 are arranged in line in the longitudinal direction of the liquid supply tank 22. Furthermore, the width direction of the plurality of flat multi-hole tubes 21 coincides with the longitudinal direction of the liquid supply tank 22.

Further, as shown in FIG. 3, the flat multi-hole tube 21 is connected to the liquid supply tank 22 in a state where the lowermost end is in contact with the bottom surface side of the inner wall surface of the liquid supply tank 22. Therefore, at least the first inlet 212a to the fifth inlet 212e at the position closest to the bottom surface of the liquid supply tank 22 among the first inlet 212a to the fifth inlet 212e is lower than the center line CL of the liquid supply tank 22. It is open.

Furthermore, in the present embodiment, the fifth inlet 212e which opens at a position farthest from the bottom of the liquid supply tank 22 among at least the first inlet 212a to the fifth inlet 212e is opened above the center line CL. The lower end surface of the flat multi-hole tube 21 is inclined so that Here, since the liquid supply tank 22 is formed in a cylindrical shape with a bottom, the center line CL of the liquid supply tank 22 is the central portion of the liquid supply tank 22 in the vertical direction.

Further, in the present embodiment, a plurality of flat multi-hole tubes 21 having the same shape are employed. Furthermore, the plurality of flat multi-hole tubes 21 are arranged such that the lower end faces are inclined in the same direction. For this reason, the opening positions of all the inlets opening into the interior of the liquid supply tank 22 regularly change in the longitudinal direction of the liquid supply tank 22.

More specifically, a plurality of predetermined fluid passages among the plurality of fluid passages formed in the plurality of flat multi-hole tubes 21 are defined as a reference fluid passage group. In the present embodiment, the first fluid passage 211a to the fifth fluid passage 211e formed in one flat multi-hole tube 21 are defined as a reference fluid passage group.

Further, the change in the opening position of the inlet in the longitudinal direction of the liquid supply tank 22 of the reference fluid passage group is defined as a reference change pattern. In this embodiment, the reference change pattern is a change in which the opening position becomes higher in the order of the first inlet 212a, the second inlet 212b, the third inlet 212c, the fourth inlet 212d, and the fifth inlet 212e. Define as

When the reference change pattern is thus defined, the opening positions of all the inlets opening into the interior of the liquid supply tank 22 regularly change the reference change pattern repeatedly in the longitudinal direction of the liquid supply tank 22. ing. Furthermore, the reference change pattern is repeated by the number of flat multi-hole tubes 21.

Therefore, a plurality of first inlets 212 a, which are bottom side inlets, are provided for the number of flat multi-hole tubes 21. Further, the adjacent first inlets 212a are arranged at a constant interval (in the present embodiment, an arrangement interval in the width direction of the flat multi-hole tube 21).

The fluid outflow tank 23 is a fluid outflow portion for collecting and flowing out the gas phase working fluid that has evaporated when flowing through the flat multi-hole tube 21. The fluid outflow tank 23 is formed of a metal similar to the flat multi-hole tube 21 and has a bottomed cylindrical shape extending in the horizontal direction. At one longitudinal end of the fluid outflow tank 23, there is provided a fluid outlet 23a through which the working fluid in the gas phase flows out.

It is desirable that the fluid outflow tank 23 be larger in diameter than the liquid supply tank 22 in order to reduce the pressure loss that occurs when the working fluid in the gas phase flows.

On the side surface of the fluid outflow tank 23, a plurality of insertion holes 23b to which the upper end side of the flat multi-hole tube 21 is inserted and connected are formed. The insertion holes 23 b of the fluid outflow tank 23 are formed in line in the longitudinal direction of the fluid outflow tank 23 so that flat surfaces on both sides of the flat multi-hole tube 21 are disposed on the same plane.

Therefore, the plurality of flat multi-hole tubes 21 are arranged in line in the longitudinal direction of the fluid outflow tank 23. Furthermore, the width direction of the plurality of flat multi-hole tubes 21 coincides with the longitudinal direction of the fluid outflow tank 23. Accordingly, the longitudinal direction of the liquid supply tank 22 and the longitudinal direction of the fluid outflow tank 23 also coincide.

Moreover, the evaporator 2 of this embodiment is manufactured by integrating each component, such as several flat multi hole tubes 21, the liquid supply tank 22, and the fluid outflow tank 23, by brazing joining.

Next, an arrangement relationship between the evaporator 2 and the battery pack BP will be described. As shown in FIG. 2, the longitudinal direction of the liquid supply tank 22 and the longitudinal direction of the fluid outflow tank 23 coincide with the stacking direction of the battery cells BC. Furthermore, as shown in FIG. 4, the battery cells BC of the battery pack BP are disposed on both sides of the flat surface of the flat multi-hole tube 21 in each row. FIG. 4 is a view of the evaporator 2 and the battery pack BP as viewed from the stacking direction of the battery pack BP.

More specifically, the assembled battery BP is disposed such that the side surfaces of the battery cells BC forming one row are thermally connected to one flat surface of the plurality of flat multi-hole tubes 21. In other words, in the battery cells BC forming one row, the heat of the battery cells BC forming one row flows through the flat multi-hole tube 21 via the flat surface of the flat multi-hole tube 21 The heat transfer to the working fluid is arranged.

Furthermore, the side surfaces of the battery cells BC forming the other row are disposed so as to be thermally connected to the other flat surfaces of the plurality of flat multi-hole tubes 21. In other words, in the battery cell BC forming the other row, the heat of the battery cell BC forming the other row flows through the flat multi-hole tube 21 via the other flat surface of the flat multi-hole tube 21 The heat transfer to the working fluid is arranged.

Thus, the heat of each battery cell BC (that is, the assembled battery BP) can be transferred to the working fluid so that the working fluid is evaporated in the plurality of flat multi-hole tubes 21. Can. Therefore, the evaporation portion is formed by a portion of the working fluid tube (in the present embodiment, a plurality of flat multi-hole tubes 21) to which the heat of the battery cell BC is transferred to the working fluid.

Further, as shown in FIG. 4, a heat diffusion plate 24 and a heat conductive material 25 are disposed between the battery cell BC and the flat multi-hole tube 21 forming the evaporation portion.

The heat diffusion plate 24 diffuses the heat of the battery cell BC to a wide area of the evaporation portion. In the present embodiment, a plate-like member made of a metal (specifically, an aluminum alloy) excellent in heat conductivity is adopted as the heat diffusion plate 24. The heat transfer material 25 promotes heat transfer from the battery cell BC to the working fluid. In the present embodiment, a resin sheet having electrical insulation and high thermal conductivity is adopted as the heat conductive material 25.

In FIG. 4, a clearance is provided between the flat multi-hole tube 21, the heat diffusion plate 24, the heat conductive material 25, and the battery cell BC for the sake of clarity of the illustration, but in fact The hole tube 21 and the heat conductive material 25, the heat diffusion plate 24 and the heat conductive material 25, and the battery cell BC and the heat conductive material 25 are in contact with each other.

Further, as shown in FIGS. 2 and 3, the arrangement interval in the width direction of the flat multi-hole tube 21 of the present embodiment is set to be equal to the width dimension in the stacking direction of the battery cells BC. Furthermore, the number of flat multi-hole tubes 21 is the same as the number of battery cells BC.

For this reason, the reference change pattern of the opening position of each inlet portion of the flat multi-hole tube 21 described above is regularly repeated by the number of the flat multi-hole tube 21 for each width dimension of the battery cell BC. Therefore, when viewed in the horizontal direction perpendicular to the stacking direction of the battery cells BC, the respective battery cells BC are arranged to overlap with the first fluid passage 211a.

Next, the operation of the thermosiphon cooling device 1 will be described. When the assembled battery BP generates heat by charge and discharge, the working fluid in the liquid phase absorbs heat of the assembled battery BP and evaporates in the flat multi-hole tube 21 forming the evaporation portion. Thereby, the battery pack BP is cooled, and the temperature rise of the battery pack BP is suppressed.

The working fluid in the gas phase evaporated in the flat multi-hole tube 21 moves upward through the respective fluid passages of the flat multi-hole tube 21 and gathers in the fluid outflow tank 23 due to the density difference between the liquid phase and the working fluid. Do. The gas-phase working fluid collected in the fluid outflow tank 23 flows out of the fluid outlet 23 a and flows into the condenser 4 through the gas-phase fluid piping 3.

The gas phase working fluid that has flowed into the condenser 4 is absorbed by the low pressure refrigerant of the refrigeration cycle and cooled. Thus, the working fluid flowing into the condenser 4 is condensed. Then, the exhaust heat of the battery pack BP is dissipated to the refrigerant of the refrigeration cycle via the working fluid.

The working fluid in the liquid phase condensed in the condenser 4 moves downward by the action of gravity. Then, the fluid flows from the fluid inlet 22 a of the evaporator 2 to the liquid supply tank 22 through the liquid phase fluid piping 5. The working fluid in the liquid phase that has flowed into the liquid supply tank 22 is distributed to each fluid passage of the flat multi-hole tube 21 again.

As described above, in the thermosiphon type cooling device 1, the working fluid is naturally circulated without the need for a working fluid transfer device such as a compressor or a pump to discharge the battery pack BP which is the object to be cooled. Heat can be continuously dissipated to the outside. That is, according to the thermosiphon cooling device 1, the battery assembly BP can be cooled efficiently and continuously.

By the way, the operation of the thermosiphon cooling device 1 described above is based on the premise that the liquid supply tank 22 is filled with the working fluid of the liquid phase. However, when the cooling of the working fluid in the condenser 4 becomes insufficient, or when the working fluid in the liquid phase in the liquid phase fluid piping 5 or the liquid supply tank 22 receives heat from the outside, the inside of the liquid supply tank 22 In some cases, the working fluid in the gas phase may be mixed.

Then, if the working fluid in the gas phase is mixed into the liquid supply tank 22, the working fluid in the liquid phase can not be uniformly supplied from the liquid supply tank 22 to all the flat multi-hole tubes 21. Furthermore, in the flat multi-hole tube 21 to which the working fluid in the liquid phase is not supplied, the working fluid can not be evaporated, so that the dryout may occur that the cooling of the battery cell BC becomes insufficient.

That is, when the working fluid in the gas phase is mixed in the liquid supply tank 22, the entire assembled battery BP can not be cooled uniformly, which may lower the performance of the assembled battery BP.

On the other hand, in the evaporator 2 of the present embodiment, the opening positions of the first inlet portion 212a to the fifth inlet portion 212e of the first fluid passage 211a to the fifth fluid passage 211e formed in the flat multi-hole tube 21 It is different in the vertical direction. For this reason, even if the working fluid of the liquid phase in the liquid supply tank 22 is mixed with the working fluid of the gas phase, the inlet portion is lower on the lower side among the first fluid passage 211a to the fifth fluid passage 211e. It becomes easy to be supplied to the open fluid passage.

That is, the working fluid in the liquid phase in the liquid supply tank 22 is easily supplied to the first fluid passage 211a having the first inlet 212a which is the bottom side inlet.

Furthermore, in the evaporator 2 of the present embodiment, since the plurality of flat multi-hole tubes 21 are arranged in the longitudinal direction of the liquid supply tank 22, the first fluid passage 211a is fixed in the longitudinal direction of the liquid supply tank 22. It can be spaced apart. In other words, the fluid passages to which the liquid phase working fluid is likely to be supplied can be arranged at regular intervals in the working fluid tube forming the evaporation portion.

Therefore, the working fluid in the liquid phase can be evenly distributed from the liquid supply tank 22 to the entire region of the evaporation section. As a result, even if the working fluid of the gas phase is mixed in the liquid supply tank 22, the whole of the assembled battery BP can be uniformly cooled by the latent heat of vaporization of the working fluid in the entire region of the evaporating unit.

Furthermore, when the arrangement interval in the width direction of the flat multi-hole tube 21 and the width dimension in the stacking direction of the battery cells BC are set equal, when viewed from the horizontal direction perpendicular to the stacking direction of the battery cells BC, The battery cell BC and the first fluid passage 211a are arranged in an overlapping manner. Therefore, any battery cell BC can be cooled by the latent heat of vaporization of the working fluid in the liquid phase that has flowed into the first fluid passage 211a. As a result, it is possible to suppress deterioration in the overall performance of the battery pack BP.

Moreover, in the evaporator 2 of this embodiment, the several flat multi hole tube 21 is employ | adopted as a working fluid tube. Furthermore, the lower end surface of the flat multi-hole tube 21 is inclined with respect to the horizontal plane. Therefore, the inside of the working fluid tube can be easily divided into a plurality of fluid passages. Furthermore, the opening positions of the inlets of the respective fluid passages can be easily made different positions in the vertical direction.

In addition to this, the flat multi-hole tube 21 can be manufactured by obliquely cutting the end of a long metal member formed by extrusion molding or the like with respect to the longitudinal direction. Therefore, the flat multi-hole tube 21 whose end face is a cut surface can be cut out from the remaining metal members that have been cut. As a result, the yield rate at the time of manufacturing the flat multi-hole tube 21 can be improved without wasting the raw material of the flat multi-hole tube 21.

Further, in the evaporator 2 of the present embodiment, the lowermost end portion of the flat multi-hole tube 21 is in contact with the inner wall surface of the liquid supply tank 22. According to this, the flat multi-hole tube 21 can be easily positioned inside the liquid supply tank 22. That is, the vertical alignment of the first inlet 212 a serving as the bottom side inlet in each flat multi-hole tube 21 can be easily performed.

Further, in the evaporator 2 of the present embodiment, at least the first inlet 212 a is opened below the center line CL of the liquid supply tank 22, and at least the fifth inlet 212 e is the center line of the liquid supply tank 22. It is opened above CL.

According to this, it is easy to secure the distance in the height direction between the opening position of the first inlet 212a and the opening position of the fifth inlet 212e. Therefore, even if the center line CL of the liquid supply tank 22 and the liquid level in the liquid supply tank 22 are inclined from the horizontal direction due to the acceleration or deceleration of the electric vehicle or the inclination of the vehicle body, the liquid phase in some first fluid passages 211a It is easy to suppress that the working fluid of the above is supplied unevenly.

Second Embodiment
In the present embodiment, as shown in FIG. 5 with respect to the first embodiment, an example in which the change pattern of the opening position of the inlet portion of each fluid passage of the flat multi-hole tube 21 (that is, the reference change pattern) is changed Explain. FIG. 5 is a drawing corresponding to FIG. 3 described in the first embodiment. In FIG. 5, the same or equivalent parts as in the first embodiment are denoted by the same reference numerals. The same applies to the following drawings.

Specifically, in the present embodiment, the first inlet 212a, the second inlet 212b, the fourth inlet 212d, and the fifth inlet 212e have the same height and are lower than the center line CL of the liquid supply tank 22. It is open at the side. In addition, the third inlet 212 c opens above the center line CL of the liquid supply tank 22. Therefore, in the present embodiment, the first inlet 212a, the second inlet 212b, the fourth inlet 212d, and the fifth inlet 212e are bottom side inlets.

The configuration and operation of the other evaporator 2 and the thermosiphon cooling device 1 are the same as in the first embodiment. Therefore, also in the evaporator 2 of this embodiment, the same effect as that of the first embodiment can be obtained.

More specifically, in the present embodiment, although all the bottom side inlets are not regularly arranged at regular intervals, each flat multi-hole tube 21 is provided with at least one or more bottom side inlets. It is done. According to this, the working fluid in the liquid phase can be distributed from the liquid supply tank 22 to the flat multi-hole tubes 21.

Moreover, when another expression is used, in the present embodiment, when focusing on a part of the bottom side inlet part (for example, the fifth inlet part 212e), the part of the bottom side inlet part extends over the entire area of the evaporation part. It is arranged at regular intervals. Therefore, the working fluid in the liquid phase can be distributed from the liquid supply tank 22 to the entire region of the evaporation section.

As a result, also in the evaporator 2 of the present embodiment, as in the first embodiment, even if the working fluid of the gas phase is mixed in the liquid supply tank 22, the latent heat of vaporization of the working fluid in the entire region of the evaporating unit The entire assembled battery BP can be cooled uniformly.

Third Embodiment
In this embodiment, an example in which the configuration of the evaporator 2 is changed as shown in FIGS. 6 and 7 will be described with respect to the first embodiment.

Specifically, the evaporator 2 of the present embodiment is provided with a flat multi-hole tube 26 formed in a plate shape as a working fluid tube. The flat multi-hole tube 26 is formed with a plurality of through holes extending in the vertical direction. The plurality of through holes are arranged in a line along the plate surface (i.e., flat surface). Therefore, the inside of the flat multi-hole tube 26 is divided into a plurality of fluid passages by a plurality of through holes as in the first embodiment.

Such a flat multi-hole tube 26 can be manufactured by extrusion molding or the like in the same manner as the flat multi-hole tube 21 described in the first embodiment.

Further, on the side surface of the liquid supply tank 22 of the present embodiment, one insertion hole 22b is formed, to which the lower end of the flat multi-hole tube 26 is inserted and connected. The insertion hole 22 b of the liquid supply tank 22 is formed in a flat shape extending in the longitudinal direction of the liquid supply tank 22. Similarly, one flat insertion hole 23 b is formed on the side surface of the fluid outflow tank 23 to which the upper end of the flat multi-hole tube 26 is inserted and connected.

Furthermore, as shown in FIG. 7, the lower end surface of the flat multi-hole tube 26 is inclined so that a pointed head 26 a pointed downward may be formed at a plurality of locations when viewed from the horizontal direction. There is.

More specifically, in the present embodiment, when a predetermined number (12 in the present embodiment) of fluid passages is used as the reference fluid passage group, each inlet portion of the reference fluid passage group corresponds to that of the liquid supply tank 22. In the reference change pattern, the half first half opening positions are sequentially lowered in the longitudinal direction, and the second half half opening positions are sequentially polygonal. That is, in the reference fluid passage group, the sharp head 26 a is formed at the longitudinal center of the liquid supply tank 22.

The opening positions of all the inlets of the flat multi-hole tube 26 opened inside the liquid supply tank 22 regularly change the reference change pattern in the longitudinal direction of the liquid supply tank 22. .

The flat multi-hole tube 26 is connected with the pointed head 26 a in contact with the inner wall surface of the liquid supply tank 22. Therefore, in the present embodiment, the inlet portion overlapping with or adjacent to the pointed portion 26a is the bottom side inlet portion 212f. The bottom side inlet portion 212f is arranged to be able to uniformly cool the battery cells BC, as in the second embodiment.

Moreover, the dimension of the height direction is expanding toward the longitudinal direction one end side in which the fluid outflow port 23a was formed of the fluid outflow tank 23 of this embodiment. That is, in the fluid outflow tank 23 of the present embodiment, the passage cross-sectional area perpendicular to the longitudinal direction is enlarged as it goes to the one end side in the longitudinal direction.

The configuration and operation of the other evaporator 2 and the thermosiphon cooling device 1 are the same as in the first embodiment. Therefore, also in the evaporator 2 of the present embodiment, as in the second embodiment, even if the working fluid of the gas phase is mixed in the liquid supply tank 22, the latent heat of vaporization of the working fluid in the entire region of the evaporating unit The entire battery BP can be cooled evenly.

Further, in the present embodiment, as shown in FIG. 6, as the fluid outflow tank 23, one in which the passage cross-sectional area is expanded along with the longitudinal direction one end side where the fluid outlet 23 a is formed is adopted. . According to this, it is possible to reduce the pressure loss when the gas phase working fluid flows through the fluid outflow tank 23, and it is easy to naturally circulate the working fluid.

Fourth Embodiment
In the present embodiment, as shown in FIG. 8 with respect to the third embodiment, an example in which the change pattern of the opening position of the inlet portion of each fluid passage of the flat multi-hole tube 26 (that is, the reference change pattern) is changed Explain.

Specifically, in the reference change pattern of the present embodiment, as in the second embodiment, the inlet portion is the same as the one opened at the same height below the center line CL of the liquid supply tank 22, and the liquid supply A reference change pattern is provided in which two types are provided: one opening at the same height on the upper side of the center line CL of the tank 22.

The configuration and operation of the other evaporator 2 and the thermosiphon cooling device 1 are the same as in the first embodiment. Therefore, also in the evaporator 2 of the present embodiment, as in the third embodiment, even if the working fluid of the gas phase is mixed in the liquid supply tank 22, the latent heat of vaporization of the working fluid in the entire region of the evaporating unit The entire battery BP can be cooled evenly.

Fifth Embodiment
In the present embodiment, as shown in FIG. 9, an evaporator 20 is described in which projections and depressions are formed on a plate surface, and a pair of first plate members 271 and a second plate member 272 are pasted together.

On the lower side of the first plate member 271, a first liquid supply forming portion 271a recessed toward the side away from the second plate member 272 is formed. The first liquid supply forming portion 271a is formed in a shape extending in the horizontal direction. A first fluid outflow forming portion 271 b recessed on the side away from the second plate member 272 is formed on the upper side of the first plate member 271. The first fluid outflow formation portion 271b is formed in a shape extending in the horizontal direction.

A plurality of first concave portions of the first plate member 271 in the vertical direction and between the first liquid supply forming portion 271 a and the first fluid outflow forming portion 271 b are separated from the second plate member 272. The tube forming portion 271c is formed. Each first tube forming portion 271c is recessed in a vertically extending shape so as to connect the first liquid supply forming portion 271a and the first fluid outflow forming portion 271b. The respective first tube forming portions 271c are arranged at equal intervals in the horizontal direction.

On the other hand, the second liquid supply forming portion 272a recessed on the side away from the first plate member 271 is located below the second plate member 272 and at a position where it overlaps with the first liquid supply forming portion 271a in the horizontal direction. It is formed. A second fluid outflow forming portion 272b recessed on the side away from the first plate member 271 is formed at a position above the second plate member 272 and in a position horizontally overlapping with the first fluid outflow forming portion 271b. ing.

A plurality of first tube forming portions 271 c of the first plate member 271 are provided at the central portion in the vertical direction of the second plate member 272 and between the second liquid supply forming portion 272 a and the second fluid outflow forming portion 272 b. A flat surface portion 272c to which the formed portion is bonded is formed.

Further, on the other end side in the longitudinal direction of the second liquid supply formation portion 272a of the second plate member 272, a fluid inflow port 22a is provided to which the working fluid of the liquid phase condensed by the condenser 4 flows. At one end side in the longitudinal direction of the second fluid outflow forming portion 272b of the second plate member 272, a fluid outflow port 23a which causes the working fluid of the gas phase to flow out is provided.

Therefore, when the first plate member 271 and the second plate member 272 are bonded, the first liquid supply forming portion 271a and the second liquid supply forming portion 272a correspond to the liquid supply tank 22 described in the first embodiment. A liquid supply tank portion 221 as a configuration to be formed is formed. The liquid supply tank portion 221 is formed in a bottomed cylindrical shape having a rectangular cross section.

The first fluid outflow formation portion 271b and the second fluid outflow formation portion 272b form a fluid outflow tank portion 231 corresponding to the fluid outflow tank 23 described in the first embodiment. As the fluid outflow tank portion 231 goes to the one end side in the longitudinal direction, the passage cross-sectional area perpendicular to the longitudinal direction is enlarged.

Further, the first tube forming portion 271c and the flat surface portion 272c form a plate tube 211 which causes the working fluid to flow from the lower side to the upper side. Furthermore, in the present embodiment, a sub-tube 273 for dividing the inside of the first tube forming portion 271c into a plurality of fluid passages is disposed inside the first tube forming portion 271c. Therefore, the working fluid tube of the present embodiment includes the plate tube 211 and the sub tube 273.

The sub tube 273 is a flat multi-hole tube in which a plurality of through holes are formed. As shown in FIG. 10, the inside of the sub-tube 273 is a first fluid passage 211g, a second fluid passage 211h, and a third fluid passage 211i (hereinafter referred to as "first fluid passage 211g to third fluid passage 211i") Are divided into three fluid passages. In addition, in FIG. 10, the joint surface at the time of bonding together the 1st plate member 271 and the 2nd plate member 272 is shown by hatching hatching for clarification of illustration. The same applies to FIGS. 11 and 12 described later.

The width dimension of the sub-tube 273 is set smaller than the width dimension of the first tube forming portion 271c. For this reason, the fourth fluid passage 211j and the fifth fluid passage 211k are formed in the gap between both sides in the width direction of the sub-tube 273 and the inner wall surface of the first tube forming portion 271c.

The lower end portion of the sub tube 273 extends into the liquid supply tank portion 221. Therefore, the first inlet 212g, the second inlet 212h, and the third inlet 212i (hereinafter referred to as "the first inlet 212g to the third inlet") open at the lower end of the first fluid passage 211g to the third fluid passage 211i. The portion 212i ′ ′ is opened inside the liquid supply tank portion 221. The first inlet portion 212g to the third inlet portion 212i are opened below the fourth inlet portion 212j and the fifth inlet portion 212k which open at the lower end portions of the fourth fluid passage 211j and the fifth fluid passage 211k. ing.

More specifically, the first inlet portion 212g to the third inlet portion 212i are opened at the same height below the center in the vertical direction of the liquid supply tank portion 221. Therefore, in the present embodiment, the first inlet portion 212g to the third inlet portion 212i are the bottom side inlet portion.

The configuration and operation of the other thermosiphon cooling device 1 are the same as in the first embodiment. As described above, the evaporator 20 has substantially the same configuration as the evaporator 2 described in the first embodiment. Therefore, also in the evaporator 20 of the present embodiment, as in the first embodiment, even if the working fluid of the gas phase mixes in the liquid supply tank portion 221, the latent heat of vaporization of the working fluid in the entire region of the evaporating portion The entire assembled battery BP can be cooled uniformly.

Furthermore, as a modification of the present embodiment, as shown in FIG. 11, the opening positions of the first inlet 212 g to the third inlet 212 i opening at the lower end of the sub tube 273 are similar to the first embodiment. It may be changed in the direction.

Further, any one of the fourth fluid passage 211 j and the fifth fluid passage 211 k may be provided.

When the width dimension of the sub-tube 273 and the width dimension of the first tube forming portion 271c are set equal, the fourth fluid passage 211j and the fifth fluid passage 211k are not formed. In this case, as shown in FIG. 12, the opening positions of the first inlet portion 212g to the third inlet portion 212i are changed in the vertical direction, and any one (in the present embodiment, the first inlet portion 212g) is on the bottom side By using the inlet portion, the same effect as that of the first embodiment can be obtained.

Sixth Embodiment
In the present embodiment, as shown in FIGS. 13 and 14, an example in which the rectifying plate 28 is disposed in the liquid supply tank 22 will be described with respect to the first embodiment. The straightening vane 28 is a plate-like member that suppresses the concentration of the working fluid in the gas phase at a high position in the liquid supply tank 22 when the vehicle is inclined or the like. That is, the straightening vane 28 has a function of suppressing the working fluid from moving inside the liquid supply tank 22 when the vehicle is inclined or the like.

The current plate 28 is made of the same metal as the liquid supply tank 22 and is brazed to the upper side of the inner wall surface of the liquid supply tank 22. As shown in FIG. 13, the straightening vanes 28 are disposed between adjacent flat multi-hole tubes 21. Therefore, the thickness of the flow straightening plate 28 is thinner than the distance between adjacent flat multi-hole tubes 21.

The straightening vanes 28 are formed in a semicircular shape when viewed from the longitudinal direction of the liquid supply tank 22 as shown in FIG. Therefore, the baffle plate 28 closes the upper half of the liquid supply tank 22.

The configuration and operation of the other evaporator 2 and the thermosiphon cooling device 1 are the same as in the first embodiment. Accordingly, in the evaporator 2 of the present embodiment, as in the first embodiment, even if the working fluid of the gas phase is mixed in the liquid supply tank 22, the latent heat of vaporization of the working fluid in the entire region of the evaporating unit The entire battery BP can be cooled evenly.

Furthermore, in the evaporator 2 of the present embodiment, since the rectifying plate 28 is disposed, the center line CL of the liquid supply tank 22 and the liquid level in the liquid supply tank 22 are determined by acceleration and deceleration of the electric vehicle and inclination of the vehicle body. Even when tilted from the horizontal direction, movement of the working fluid in the liquid phase inside the liquid supply tank 22 is suppressed.

Therefore, when the center line CL of the liquid supply tank 22 and the liquid level in the liquid supply tank 22 are inclined from the horizontal direction, the working fluid in the liquid phase is not supplied to some of the first fluid passages 211a. It can be suppressed. Thereby, the entire assembled battery BP can be cooled uniformly. Furthermore, according to the straightening vanes 28, it is possible to suppress the generation of abnormal noise that occurs when the working fluid in the liquid phase mixes with the working fluid in the gas phase and moves in the liquid supply tank 22.

(Other embodiments)
The present disclosure is not limited to the above-described embodiment, and can be variously modified as follows without departing from the spirit of the present disclosure. In addition, the means disclosed in each of the above embodiments may be combined as appropriate in the feasible range.

(1) In the above-mentioned embodiment, although the example which made the battery pack BP the cooling object of the

evaporators

2 and 20 was explained, the cooling object is not limited to the battery pack BP. The thermosiphon-type cooling device 1 including the

evaporators

2 and 20 of the present embodiment is suitably used to cool an object to be cooled which is desirably uniformly cooled throughout.

Further, the battery pack BP as the object to be cooled is not limited to one mounted on an electric vehicle. For example, it may be mounted on a hybrid vehicle or the like which obtains driving power for traveling from an internal combustion engine (engine) and a traveling electric motor. In addition, the battery pack BP may include battery cells BC electrically connected in parallel.

Moreover, although the above-mentioned embodiment demonstrated the example which laminated | stacked battery cell BC to 2 rows and arrange | positioned 1 row each on the both sides of the evaporation part of the evaporator 2, the arrangement aspect of the battery cell BC and the evaporator 2 is this It is not limited to. The number of rows in which the battery cells BC are stacked is not limited to two, and the number of evaporators 2 is not limited to one.

For example, the battery cells BC may be stacked in one row and disposed so as to be thermally connected to one surface of the evaporation portion of the

evaporator

2 or 20. Furthermore, the battery cells BC may be stacked in four rows, and one row may be arranged on both sides of the evaporators of the two

evaporators

2 and 20. In this case, the two evaporators 2 may be connected in parallel to the working fluid flow in the thermosiphon cooling device 1.

(2) Each component which comprises

evaporator

2 and 20 is not limited to what was indicated by the above-mentioned embodiment.

For example, the liquid supply tank 22 of the evaporator 2 is not limited to one formed in a circular cross-sectional shape, and is formed in a polygonal cross-sectional shape like the liquid supply tank portion 221 of the evaporator 20 described in the fifth embodiment. It may be done. The same applies to the fluid outflow tank 23.

In the liquid supply tank 22 having a polygonal cross section, a line connecting the center of gravity of the cross section may be defined as a central portion in the upper limit direction. In addition, the central portion in the vertical direction of the liquid supply tank 22 in which the cross-sectional shape changes may be defined as a line connecting the central portions in the vertical direction of the internal space of the liquid supply tank 22 when viewed from the horizontal direction.

The heat diffusion plate 24 may be made of another metal (for example, copper). Furthermore, it is not limited to a metal, You may be formed with the carbon material (for example, carbon fiber, a carbon nanotube) which is excellent in heat conductivity. The heat conductive material 25 may be in the form of grease. Furthermore, if the electrical insulation between the evaporator 2 and the battery pack BP can be secured, the heat conductive material 25 may be eliminated and the evaporator 2 may be in direct contact with the battery pack BP.

Although the example which employ | adopted the flat multi hole tube manufactured by extrusion molding etc. was demonstrated as a subtube 273 in 5th Embodiment, a subtube is not limited to this. For example, a welded tube manufactured by bending and joining plate members may be employed. Of course, the sub-tube may be formed by arranging one or more single-hole pipes thinner than the width direction of the first tube forming portion 271c.

Furthermore, although the example which arrange | positioned the subtube 273 in the inside of all the 1st tube formation parts 271c was demonstrated in 5th Embodiment, arrangement | positioning of the subtube 273 is not limited to this. As long as the entire object to be cooled can be cooled uniformly, for example, as shown in FIG. 15, a first tube forming portion 271 c in which the sub tube 273 is not disposed may be provided.

In this case, the first tube forming portion in which the sub tube 273 is disposed, such as alternately arranging the first tube forming portion 271 c in which the sub tube 273 is disposed and the first tube forming portion 271 c in which the sub tube 273 is not disposed It is desirable that the first tube forming portion 271 c in which the sub tube 271 c is not disposed is regularly disposed in the longitudinal direction of the liquid supply tank portion 221.

In the sixth embodiment, when viewed from the longitudinal direction of the liquid supply tank 22, the example has been described in which the straightening vane 28 formed in a semicircular shape is adopted, but the shape of the straightening vane 28 is not limited thereto. If it can be joined to the inner wall surface of the liquid supply tank 22, it may be formed in a rectangular shape. Furthermore, as long as the working fluid in the liquid phase can be prevented from moving inside the liquid supply tank 22, it may be arranged to close any part of the liquid supply tank 22.

(3) Each component apparatus which comprises the thermosiphon type cooling device 1 is not limited to what was disclosed by the above-mentioned embodiment.

The condenser 4 is not limited to the heat exchanger disclosed in the above-described embodiment as long as it can condense the working fluid in the gas phase, and various types of condensers can be adopted. . For example, a heat exchanger may be adopted as the condenser 4 for exchanging heat between the gas phase working fluid and the outside air or LLC (cooling water).

Furthermore, as the condenser 4, a cooling device may be adopted which cools the working fluid in the gas phase with the cold heat generated by a Peltier element or the like. A plurality of condensers 4 may be provided and connected in parallel or in series to the flow of the working fluid.

Further, in the thermosiphon cooling device 1 described in the first embodiment, one working fluid pipe may be used except the evaporator 2. That is, in the working fluid piping, the portion that cools and condenses the working fluid is the condensation portion that functions as a condenser, the portion on the working fluid flow upstream side of the condensation portion is the gas phase fluid piping 3, and the operation of the condensation portion The portion on the downstream side of the fluid flow may be used as the liquid-phase fluid piping 5.

Moreover, although the above-mentioned embodiment demonstrated the example which employ | adopted R134a as a working fluid, a working fluid is not limited to this. Another fluorocarbon-based refrigerant (eg, R1234yf) may be employed as the working fluid. Furthermore, the heat medium such as propane, carbon dioxide and alcohol may be employed without being limited to the fluorocarbon refrigerant.

Although the disclosure has been described with reference to examples, it is understood that the disclosure is not limited to the disclosed examples or structures. Rather, the present disclosure includes various modifications and variations within the equivalent range. In addition, although various elements of the present disclosure are illustrated by various combinations and forms, other combinations and forms including more elements, fewer elements, or only one of these elements Are also within the scope and scope of the present disclosure.

Claims

An evaporator applied to a thermosyphon cooling system (1), comprising:
Working fluid tubes (21, 26, 211) for circulating working fluid;
A liquid supply unit (22, 221) connected to the lower end of the working fluid tube to supply the working fluid of the liquid phase to the working fluid tube;
The working fluid tube forms an evaporation unit that evaporates the working fluid by absorbing heat of the object to be cooled (BP) by the working fluid in a liquid phase flowing therethrough.
The inside of the working fluid tube is divided into a plurality of fluid passages (211 a, 211 b, 211 c, 211 d, 211 e, 211 h, 211 h, 211 i, 211 j, and 211 k) for passing the working fluid from the lower side to the upper side. Yes,
At least a part of the inlets (212a, 212b, 212c, 212d, 212e, 212f, 212g, 212h, 212i, 212j, 212k) of the plurality of fluid passages are opened inside the liquid supply unit, Evaporators whose opening positions are different from each other in the vertical direction.
Among the inlets, when the inlet opening at the position closest to the bottom surface of the liquid supply unit is defined as the bottom side inlet,
A plurality of bottom side inlets are provided,
The evaporator according to claim 1, wherein the plurality of bottom side inlets are spaced apart from each other.
The object to be cooled is a battery pack (BP) formed by stacking a plurality of battery cells (BC),
The evaporator according to claim 2, wherein each battery cell is arranged to overlap with at least one of the fluid passages having the bottom side inlets when viewed from the horizontal direction perpendicular to the stacking direction of the plurality of battery cells. .
The working fluid tube is a multi-hole tube (21, 26) in which a plurality of through holes are formed,
The evaporator according to any one of claims 1 to 3, wherein the lower end surface of the working fluid tube is formed with a portion inclined with respect to a horizontal surface.
The evaporator according to claim 4, wherein a lowermost end of the working fluid tube is in contact with an inner wall surface of the liquid supply unit.
The working fluid tube is a plate tube (211) formed by bonding a pair of plate members having projections and depressions on a plate surface, and a sub-tube disposed inside the plate tube to form the fluid passage The evaporator according to any one of claims 1 to 3, comprising (273).
At least one of the inlets of the plurality of fluid passages is opened below the vertical center of the liquid supply unit,
The evaporator according to any one of claims 1 to 6, wherein at least another one of the inlets of the plurality of fluid passages is open above the vertical center of the liquid supply unit.
The plate-shaped member (28) which suppresses that the said working fluid moves the inside of the said liquid supply part in the inside of the said liquid supply part is arrange | positioned in any one of Claim 1 thru | or 7 Evaporator.