JP7200907B2 - Energy storage stack cooling structure and energy storage stack cooling system - Google Patents

Description

The present disclosure relates to a cooling structure for an electricity storage stack and a cooling system for an electricity storage stack.

2. Description of the Related Art Electric vehicles and hybrid vehicles are equipped with a battery pack as a power storage device for supplying electric power to a motor. A battery pack includes a battery stack as a power storage stack in which a plurality of cells are arranged side by side in a predetermined arrangement direction, and a storage case that stores the battery stack. As the temperature of the battery stack rises, the output characteristics of the battery stack deteriorate, so the battery stack is cooled in the storage case.

Japanese Patent Laying-Open No. 2014-135237 (Patent Document 1) discloses a cooling structure for cooling a battery stack. In the cooling structure disclosed in Patent Document 1, the coolant for cooling the cell stack is disposed between the adjacent unit cells so as to intersect perpendicularly with the coolant supply flow path that flows along the direction in which the cells are arranged. A flow path is provided. A first end plate and a second end plate are arranged on both sides of the cell stack in the arrangement direction, and the first end plate is arranged on the inlet side of the coolant supply channel.

The first end plate includes a main body facing one end of the storage stack in the arrangement direction, and a flow dividing plate extending from the main body along the arrangement direction. is provided with an opening for taking in the coolant. The flow division plate forms a flow division space facing some of the cells arranged on one side in the arrangement direction in the coolant supply path, and the refrigerant taken into the flow division space from the opening is diverted to the some of the cells. It is directed to the coolant channel formed between the cells. As a result, the coolant can flow to the one end side of the battery stack where it is difficult for the coolant to flow.

JP 2014-135237 A

However, in the battery stack cooling structure disclosed in Patent Document 1, the body portion of the first end plate and the body portion of the second end plate are arranged so as to be in close contact with the adjacent unit cells. For this reason, coolant flow paths through which the coolant flows are not formed between the main body portion of the first end plate and the cell and between the second end plate and the cell. As a result, only one side of the pair of side surfaces facing the array direction is cooled in the unit cells positioned at both ends in the array direction, and both of the pair of side surface portions are cooled in the other unit cells. . As a result, the temperature of the unit cells arranged at both ends in the arrangement direction becomes higher than the temperature of the other unit cells. In such a case, temperature control of the battery stack becomes complicated because the temperature of the battery stack varies and the temperature on both sides of the power storage stack increases.

The present disclosure has been made in view of the above-described problems, and an object of the present disclosure is to provide an electricity storage stack cooling structure and an electricity storage stack that can easily manage the temperature of the electricity storage stack while suppressing variations in the temperature of the electricity storage stack. to provide a cooling system for

An electricity storage stack cooling structure based on the present disclosure includes an electricity storage stack including a plurality of electricity storage cells arranged in a predetermined arrangement direction, first end plates and second end plates arranged on both outer sides of the electricity storage stack in the arrangement direction. an end plate, a coolant supply path provided along the arrangement direction for supplying a coolant from one end side to the other end side of the electric storage stack in the arrangement direction, and two adjacent electric storage cells. and a plurality of first paths respectively provided in the gaps between them and communicating with the coolant supply path. The first end plate is configured such that a second path communicating with the coolant supply path is formed in a gap between the first end plate and the one end of the electricity storage stack. The second end plate is configured such that a third path communicating with the coolant supply path is formed in a gap between the second end plate and the other end of the electricity storage stack. The plurality of first paths, the second path, and the third path are configured such that when the electric storage stack is cooled by the refrigerant, the temperature of the electric storage cell arranged on the one end side is lower than the temperature on the other end side. The electric storage stack is configured to have a temperature distribution in which the temperature of the arranged electric storage cells increases.

With the above configuration, paths through which the coolant can pass are formed on both sides in the arrangement direction in each of the plurality of energy storage cells arranged side by side in the arrangement direction. Thereby, each of the plurality of storage cells can be cooled from both sides in the arrangement direction. As a result, it is possible to suppress variations in temperature from one end side to the other end side of the electric storage stack in the arrangement direction.

Furthermore, when the electricity storage stack is cooled by the coolant, the temperature of the electricity storage cell arranged on the other end side of the electricity storage stack in the arrangement direction becomes higher than the temperature of the electricity storage cell arranged on the one end side of the electricity storage stack in the arrangement direction. A plurality of first paths, second paths, and third paths are configured such that the electricity storage stack has a temperature distribution, so that the electricity storage cell is arranged at the other end of the electricity storage stack downstream in the coolant supply direction. temperature is the highest. Therefore, by managing the temperature of the storage cell arranged at the other end of the storage stack so as not to exceed the predetermined reference temperature, the temperature of the other storage cells also does not exceed the reference temperature. This makes it easier to manage the temperature of the power storage stack.

In the power storage stack cooling structure based on the present disclosure, the inlet area of the third path may be smaller than the inlet area of the second path.

According to the above configuration, it is more difficult for the coolant to enter the third path located on the downstream side in the coolant supply direction than the second path located on the upstream side in the coolant supply direction. Therefore, the temperature of the storage cell arranged at the other end of the storage stack can be easily maximized, and temperature management is facilitated.

In the power storage stack cooling structure based on the present disclosure, the first end plate is connected to a first opposing wall portion facing the one end of the power storage stack and to the first opposing wall portion, A second facing wall facing the storage cell located at the one end of the stack from the coolant supply path side may be included. It is preferable that the second opposing wall portion is provided with an opening for communicating a gap between the first opposing wall portion and the one end of the electricity storage stack and the coolant supply path. The second end plate may include a third facing wall facing the other end of the electricity storage stack. The third opposing wall portion is connected to the first wall portion and to the first wall portion on the refrigerant supply path side, and is closer to the other end side of the power storage stack than the first wall portion in the arrangement direction. A second wall portion may be provided so as to. In this case, the gap between the first wall portion and the other end of the electricity storage stack and the coolant supply path are interposed through the gap between the second wall portion and the other end of the electricity storage stack. Preferably, the distance between the second wall portion and the other end of the electricity storage stack in the arrangement direction is shorter than the width of the opening in the arrangement direction.

Also with the above configuration, the coolant is less likely to enter the third path through the gap between the second wall portion and the other end of the power storage stack than the coolant enters the second path through the opening. Therefore, the temperature of the storage cell arranged at the other end of the storage stack can be easily maximized, and temperature management is facilitated.

The power storage stack cooling structure according to the present disclosure may further include a coolant duct inserted into one end side of the coolant supply path where the first end plate is located. The first end plate may have a protrusion that protrudes in a direction opposite to the direction of insertion of the coolant duct. In this case, it is preferable that the refrigerant duct has a stopper provided so as to be able to abut against the projecting portion so that the distal end side of the refrigerant duct does not block the inlet portion of the second path.

According to the above configuration, when inserting the refrigerant duct, it is possible to prevent the tip side of the refrigerant duct from blocking the inlet portion of the second path. As a result, it is possible to prevent the temperature of the storage cells arranged on the one end side of the storage stack in the arrangement direction from rising, and to suppress the variation in the temperature of the storage stack.

A cooling system for an electricity storage stack of the present disclosure includes: the cooling structure; a coolant supply source that supplies the coolant to the coolant supply path; a thermometer for measuring the temperature of the storage cell located at the end. The control unit controls the operation of the coolant supply source so that the amount of coolant supplied increases when the temperature measured by the thermometer reaches or exceeds a predetermined temperature.

According to the above configuration, since the temperature of only the storage cell with the highest temperature is measured by the thermometer, the cooling control of the storage stack is performed based on the measurement result of the thermometer while minimizing the number of thermometers. be able to.

According to the present disclosure, it is possible to provide an electricity storage stack cooling structure and an electricity storage stack cooling system that facilitate control of the temperature of the electricity storage stack while suppressing variations in the temperature of the electricity storage stack.

1 is a diagram showing a vehicle equipped with a cooling structure for an electricity storage stack according to an embodiment; FIG. 1 is a schematic perspective view showing a cooling system provided with a cooling structure for an electricity storage stack according to an embodiment; FIG. It is the top view which looked at the main-body part of the 1st end plate which concerns on embodiment from the front side. It is the top view which looked at the main-body part of the 1st end plate which concerns on embodiment from the back side. 4 is a cross-sectional view of the first end plate along line VV shown in FIG. 3; FIG. It is the top view which looked at the main-body part of the 2nd end plate which concerns on embodiment from the front side. FIG. 7 is a cross-sectional view of the second end plate along line VII-VII shown in FIG. 6; FIG. 2 is a diagram showing a cross section of a cooling structure for an electricity storage stack according to an embodiment; FIG. 4 is a diagram showing temperature distribution of an electricity storage stack according to the embodiment; FIG. 5 is a diagram showing the periphery of a first end plate of a portion located on the coolant supply path side in a cooling structure for an electricity storage stack according to a comparative example; FIG. 10 is a diagram showing the periphery of a second end plate of a portion positioned on the coolant supply path side in a cooling structure for an electricity storage stack according to a comparative example; FIG. 5 is a diagram showing temperature distribution of an electricity storage stack according to a comparative example;

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the embodiments shown below, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated.

FIG. 1 is a schematic diagram showing a vehicle equipped with a cooling structure for an electricity storage stack according to an embodiment. As shown in FIG. 1 , a vehicle 1 is equipped with a cooling structure 10 for a power storage stack. The vehicle 1 is a hybrid vehicle that can run using the power of at least one of a motor and an engine, or an electric vehicle that runs with driving force obtained from electric energy.

The cooling structure 10 for the power storage stack includes the power storage module 2 , the housing case 3 , a coolant supply path 6 described later, and the coolant duct 4 . The power storage stack cooling structure 10 is a structure for cooling the power storage stack 20 (described later) provided in the power storage module 2 .

The power storage module 2 is housed in the housing case 3 . A coolant supply path 6 through which coolant is supplied is formed between the power storage module 2 and the housing case 3 . The coolant duct 4 is inserted into one end of the coolant supply path 6 . The coolant duct 4 is connected to a coolant supply source 5 and supplied with coolant from the coolant supply source 5 . The coolant supplied from the coolant supply source 5 is supplied to the coolant supply path 6 through the coolant duct 4 . The coolant supply source 5 is, for example, an air blower, and in this case the coolant is cooling air. Note that other refrigerant gas may be used as the refrigerant.

The coolant supplied to the coolant supply path 6 cools the power storage stack 20 and is then exhausted from an exhaust duct (not shown) connected to the storage case 3 .

FIG. 2 is a schematic perspective view showing a cooling system provided with a cooling structure for an electricity storage stack according to an embodiment. Referring to FIG. 2, the details of the power storage stack cooling structure 10 and the power storage stack cooling system 100 according to the embodiment will be described.

As shown in FIG. 2 , the storage stack cooling structure 10 includes two storage modules 2 . The two power storage modules 2 are arranged side by side in the width direction (DR2 direction in FIG. 2) of the power storage stack 20 described later. Note that the number of power storage modules 2 is not limited to two, and may be singular or three or more.

The power storage module 2 includes a power storage stack 20 , a first end plate 31 , a second end plate 32 , and a plurality of binding members 40 . In the power storage module 2 , the power storage stack 20 is sandwiched between the first end plate 31 and the second end plate 32 and restrained by the restraining member 40 .

Energy storage stack 20 includes a plurality of energy storage cells 21 arranged side by side in a predetermined arrangement direction (DR1 direction) and a plurality of spacers 22 arranged side by side in the arrangement direction. The plurality of storage cells 21 and the plurality of spacers 22 are arranged alternately.

As the electric storage cell 21, for example, a single battery can be adopted. A cell is, for example, a secondary battery such as a nickel-metal hydride battery or a lithium-ion battery. A cell has, for example, a rectangular shape. The secondary battery may use a liquid electrolyte or may use a solid electrolyte. Note that the storage cell 21 may be a unit capacitor configured to be chargeable and dischargeable.

Each of the plurality of spacers 22 is arranged in the gap between the two energy storage cells 21 adjacent to each other. The spacer 22 forms a first path 61 communicating with the coolant supply path in the gap between the two adjacent storage cells 21 .

First path 61 is formed such that the coolant is introduced from one side in the height direction (DR3 direction) of power storage stack 20 and discharged from both sides in the width direction (DR2 direction) of power storage stack 20 . ing.

The first end plate 31 and the second end plate 32 are arranged on both outer sides of the power storage stack 20 in the arrangement direction.

The first end plate 31 is arranged on one end side of the electricity storage stack 20 in the arrangement direction. The first end plate 31 is made of hard plastic or the like, for example. The first end plate 31 may be made of a metal member such as aluminum.

The first end plate 31 includes a body portion 310, a bracket portion 31a and a fixing portion 31b. The bracket portion 31a and the fixing portion 31b are attached to the main body portion 310. As shown in FIG. Bracket portion 31 a is a member for fixing power storage stack 20 to storage case 3 . The fixing portion 31b is a member for fixing the restraining member 40. As shown in FIG.

The first end plate 31 is configured such that a second path 62 communicating with the coolant supply path is formed in a gap between the first end plate 31 and one end of the electricity storage stack. Second path 62 is formed such that the coolant is introduced from one side in the height direction (DR3 direction) of power storage stack 20 and discharged from both sides in the width direction (DR2 direction) of power storage stack 20 . ing. An example of the detailed structure of the first end plate 31 will be described later with reference to FIGS. 3 to 5. FIG.

The second end plate 32 is arranged on the other end side of the electricity storage stack 20 in the arrangement direction. The second end plate 32 is made of hard plastic or the like, for example. The second end plate 32 may be made of a metal member such as aluminum.

The second end plate 32 includes a body portion 320 as a third opposing wall portion, a bracket portion 32a and a fixing portion 32b. The bracket portion 32a and the fixing portion 32b are assembled to the main body portion 320. As shown in FIG. The bracket portion 32 a is a member for fixing the electricity storage stack 20 to the housing case 3 . The fixing portion 32b is a member for fixing the restraining member 40. As shown in FIG.

The second end plate 32 is configured such that a third path 63 communicating with the refrigerant path is formed in a gap between the second end plate 32 and the other end of the electricity storage stack. Third path 63 is formed such that the coolant is introduced from one side in the height direction (DR3 direction) of power storage stack 20 and discharged from both sides in the width direction (DR2 direction) of power storage stack 20 . ing. An example of the detailed structure of the second end plate 32 will be described later with reference to FIGS. 6 and 7. FIG.

The plurality of restraining members 40 connect the first end plate 31 and the second end plate 32 while being inserted through the plurality of insertion portions 41 . The multiple storage cells 21 , the multiple spacers 22 , the first end plates 31 and the second end plates 32 are fixed by the multiple restraining members 40 while receiving a compressive load in the arrangement direction.

The plurality of insertion portions 41 are formed by connecting cylindrical portions provided on the upper portions of the spacers 22 in the arrangement direction.

The cooling system 100 includes the cooling structure 10 for the power storage stack, a coolant supply source 5 , a controller 50 , and a thermometer 51 .

The control unit 50 controls the operation of the coolant supply source 5 . Thermometer 51 measures the temperature of storage cell 21 located at the other end of storage stack 20 . A measurement result (temperature information) measured by the thermometer 51 is input to the control unit 50 . The control unit 50 controls the operation of the coolant supply source 5 based on the measurement results. Specifically, the control unit 50 controls the operation of the coolant supply source 5 so that the coolant supply amount increases when the temperature measured by the thermometer 51 reaches or exceeds a predetermined temperature.

When the coolant supply source 5 is a blower as described above, the controller 50 increases the rotation speed of the fan when the temperature measured by the thermometer 51 reaches or exceeds a predetermined temperature.

FIG. 3 is a plan view of the main body of the first end plate according to the embodiment, viewed from the front side. FIG. 4 is a plan view of the main body of the first end plate according to the embodiment, viewed from the back side. 5 is a cross-sectional view of the first end plate along line VV shown in FIG. 3. FIG. For convenience, FIG. 5 shows the storage cell 21 positioned at one end of the storage stack 20 . The first end plate 31 will be described with reference to FIGS. 3 to 5. FIG.

As shown in FIGS. 3 to 5, the first end plate 31 includes a first opposing wall portion 311, a second opposing wall portion 312, and a protruding portion 314. As shown in FIGS.

First opposing wall portion 311 extends along a direction parallel to the height direction of power storage stack 20 . The first opposing wall portion 311 faces one end of the power storage stack 20 in the arrangement direction. Specifically, the first opposing wall portion 311 faces one side surface in the arrangement direction of the storage cell 21 located at one end of the storage stack 20 . The first opposing wall portion 311 is arranged with a distance from the one-side side surface of the storage cell 21 .

The front surface 311a side of the first opposing wall portion 311 is provided substantially flat so that the bracket portion 31a and the fixing portion 31b can be assembled. A plurality of ribs 315 are provided on the back surface 311 b of the first opposing wall portion 311 . A plurality of ribs 315 are arranged in the gap S<b>1 between the first opposing wall portion 311 and the storage cell 21 . The plurality of ribs 315 form a second path 62 through which the coolant can flow in the gap S<b>1 between the first opposing wall portion 311 and the storage cell 21 .

The plurality of ribs 315 includes a rib 3151 having a substantially T-shape provided in the central portion of the back surface 311b, and a rib 3151 extending from one side in the height direction (DR3 direction) of the electricity storage stack 20 toward the other side in the height direction. , and a plurality of ribs 3152 intermittently arranged along a line directed to one side or the other side in the width direction (DR2 direction) of the electricity storage stack 20 . By forming a plurality of ribs in this way, the coolant introduced from one side in the height direction (DR3 direction) of electricity storage stack 20 is discharged to both sides in the width direction (DR2 direction) of electricity storage stack 20. .

By appropriately changing the shape of the plurality of ribs 315, the first path 61 through which the coolant flows can be changed as appropriate. Even if the second path 62 is formed such that the refrigerant introduced from one side of the power storage stack 20 in the height direction (DR3 direction) is discharged to the other side of the power storage stack 20 in the height direction (DR3 direction). good.

The second facing wall portion 312 faces the storage cell 21 located at one end of the storage stack 20 from the coolant supply path 6 (see FIG. 8) side. The second opposing wall portion 312 is connected to the first opposing wall portion 311 on the coolant supply path 6 side. The second opposing wall portion 312 is provided with an opening 313 for communicating the coolant supply path 6 with the gap S1 between the first opposing wall portion 311 and one end of the power storage stack 20 . The opening 313 forms the entrance of the second path 62 .

A pair of tubular portions are formed at both ends of the main body portion 310 in the height direction (DR3 direction), and the tubular portions form part of the insertion portion 41 through which the restraining member 40 is inserted. forming. A refrigerant duct 4 is inserted into a gap between a pair of cylindrical portions provided on one side (lower side in FIG. 3) in the height direction (DR3 direction).

Protruding portion 314 protrudes toward the outside of power storage stack 20 in the arrangement direction. The projecting portion 314 is provided so as to project in a direction opposite to the direction in which the refrigerant duct 4 is inserted.

Note that the above spacer 22 also has a plurality of ribs similar to those described above on the front and rear surfaces of the plate-like portion arranged in the gap between the adjacent storage cells 21 . As a result, the first path 61 through which the coolant can flow is formed in the gap between the storage cells 21 adjacent to each other.

FIG. 6 is a plan view of the main body of the second end plate according to the embodiment, viewed from the front side. 7 is a cross-sectional view of the second end plate along line VII-VII shown in FIG. 6. FIG. Note that FIG. 7 shows the storage cell 21 positioned at the other end of the storage stack 20 for the sake of convenience. The second end plate 32 will be described with reference to FIGS. 6 and 7. FIG.

As shown in FIGS. 6 and 7, the second end plate 32 has a body portion 320 as a third opposing wall portion. Body portion 320 faces the other end of power storage stack 20 in the arrangement direction. Specifically, main body portion 320 faces the side surface on the other side in the arrangement direction of storage cell 21 located at the other end of storage stack 20 . The body portion 320 is arranged with a distance from the other side surface of the storage cell 21 .

Body portion 320 includes a first wall portion 321 and a second wall portion 322 . The first wall portion 321 mainly faces the side surface on the other side in the arrangement direction of the storage cell 21 positioned at the other end of the storage stack 20 . The first wall portion 321 is arranged with a distance from the side surface on the other side of the storage cell 21 .

The second wall portion 322 is connected to the first wall portion 321 on one side in the height direction. The second wall portion 322 is connected to the first wall portion on the coolant supply path 6 side. The second wall portion 322 is provided to extend outward from the power storage stack 20 in the height direction. The second wall portion 322 is provided so as to protrude into the coolant supply path 6 .

The second wall portion 322 is provided closer to the other end side of the power storage stack 20 than the first wall portion 321 in the arrangement direction. That is, the distance L2 between the second wall portion 322 and the other end of the power storage stack 20 in the arrangement direction is smaller than the distance L1 between the first wall portion 321 and the other end of the power storage stack 20 in the arrangement direction.

The gap S2 between the first wall portion 321 and the other end of the electricity storage stack 20 communicates with the coolant supply path via the gap S3 between the second wall portion 322 and the other end of the electricity storage stack 20 .

The front surface 321a side of the first wall portion 321 is provided substantially flat so that the bracket portion 32a and the fixing portion 32b can be assembled. A plurality of ribs 325 are provided on the rear surface 321 b of the first wall portion 321 . A plurality of ribs 325 are arranged in the gap S2 between the first wall portion 321 and the storage cell 21 . The plurality of ribs 325 form a third path 63 through which the coolant can flow in the gap S<b>2 between the first wall portion 321 and the storage cell 21 .

The plurality of ribs 325 are provided in substantially the same manner as the plurality of ribs 315 provided on the first end plate 31 . The coolant introduced from one side in the height direction (DR3 direction) of power storage stack 20 is discharged to both sides in the width direction (DR2 direction) of power storage stack 20 by means of multiple ribs 325 .

The gap S2 between the first wall portion 321 and the other end of the electricity storage stack 20 communicates with the coolant supply path 6 via the gap S3 between the second wall portion 322 and the other end of the electricity storage stack 20 . A gap S3 between the second wall portion 322 and the other end of the power storage stack 20 serves as an inlet portion of the third path 63 .

A pair of tubular portions are formed at both ends of the main body portion 320 in the height direction (DR3 direction), and the tubular portions form part of the insertion portion 41 through which the restraining member 40 is inserted. forming.

FIG. 8 is a cross-sectional view of a cooling structure for an electricity storage stack according to the embodiment. As shown in FIG. 8, the coolant supply path 6 extends along the arrangement direction at the bottom 3a of the storage case 3, the bottom of the electricity storage stack 20, and one side of the electricity storage stack 20 in the height direction. It is an area surrounded by the portion 41 .

A tip 4 a side of the coolant duct 4 is inserted into one end side of the coolant supply path 6 . A stopper 4 b is provided on the outer surface of the refrigerant duct 4 . The stopper 4b is provided on the first end plate 31 so that the tip 4a of the coolant duct 4 does not block the inlet of the second path 62 when the coolant duct 4 is inserted into one end of the coolant supply path 6. It is provided so as to be able to abut against the projecting portion 314 .

The coolant supplied from the coolant duct 4 to the coolant supply path 6 is introduced into a plurality of first paths 61 , second paths 62 , and third paths 63 communicating with the coolant supply path 6 . Thereby, each of the plurality of storage cells 21 can be cooled from both sides in the arrangement direction. As a result, it is possible to suppress variations in temperature from one end side to the other end side of the electricity storage stack 20 in the arrangement direction.

Furthermore, the plurality of first paths 61, second paths 62, and third paths 63 are provided on one end side of the electricity storage stack 20 (the side on which the first end plate 31 is located) when the electricity storage stack 20 is cooled by the refrigerant. The electric storage stack 20 has a temperature distribution in which the temperature of the electric storage cell 21 arranged on the other end side (the side where the second end plate 32 is located) of the electric storage stack 20 is higher than the temperature of the arranged electric storage cell 21. It is configured.

For example, the inlet area of the third path 63 is smaller than the inlet area of the second path 62 . Specifically, the distance L4 between the second wall portion 322 and the other end of the power storage stack 20 in the arrangement direction is equal to the opening provided in the second opposing wall portion 312 of the first end plate 31 as described above. It is shorter than the width L3 along the 313 arrangement direction. The inlet area of the first path 61 may be substantially the same as the inlet area of the second path 62 .

By configuring the plurality of first paths 61, the second paths 62, and the third paths 63 in this way, the second path positioned upstream in the coolant supply direction is positioned downstream in the coolant supply direction. Refrigerant is less likely to enter the third path located at . Therefore, the temperature of the storage cell 21 arranged at the other end of the storage stack 20 can be maximized.

As a result, by managing the temperature of the storage cell 21 arranged at the other end of the storage stack 20 so as not to exceed the predetermined reference temperature, the temperature of the other storage cells 21 is automatically prevented from exceeding the reference temperature. Gone. This makes it easier to manage the temperature of the power storage stack 20 .

FIG. 9 is a diagram showing the temperature distribution of the power storage stack according to the embodiment. The horizontal axis of FIG. 9 indicates the numbers (cell numbers) of the plurality of storage cells 21 arranged. The vertical axis in FIG. 9 indicates the temperature of the storage cell. The temperature distribution of the electricity storage stack 20 cooled by the cooling structure for the electricity storage stack will be described with reference to FIG. 9 .

As shown in FIG. 9, the storage stack 20 has a plurality of storage cells 21 arranged side by side. As described above, the power storage stack 20 cooled by the power storage stack cooling structure including the plurality of first paths 61, the second paths 62, and the third paths 63 is arranged at one end side of the power storage stack 20. It has a temperature distribution in which the temperature of the storage cell arranged on the other end side is higher than the temperature of the storage cell.

Although the temperature of the storage cells arranged on one end side of the storage stack 20 slightly fluctuates up and down, the temperature gradually increases from the one end side of the storage stack 20 toward the other end side of the storage stack 20 . The temperature of the storage cell 21 located at the other end of the storage stack 20 is the highest. The temperature difference between the highest storage cell temperature and the lowest storage cell temperature is smaller than the temperature difference in the later-described comparative example.

(Comparative example)
FIG. 10 is a diagram showing the periphery of the first end plate of the portion located on the coolant supply path side in the cooling structure for the electricity storage stack according to the comparative example. FIG. 11 is a diagram showing the periphery of the second end plate of the portion located on the coolant supply path side in the cooling structure for the electricity storage stack according to the comparative example. A power storage stack cooling structure 10X in a comparative example will be described with reference to FIGS. 10 and 11. FIG.

The power storage stack cooling structure 10X in the comparative example differs from the power storage stack cooling structure 10 according to the embodiment in the configuration of the first end plate 31X and the second end plate 32X. Other configurations are substantially the same.

As shown in FIG. 10, the first end plate 31X differs from the first end plate 31 according to the embodiment in that the second opposing wall portion 312 is not provided with an opening. In the power storage stack cooling structure 10X including the first end plate 31X, the gap S1 between the first opposing wall portion 311 and one end of the power storage stack 20 does not communicate with the coolant supply path 6 .

As shown in FIG. 11, the second end plate 32X closes the gap S2 between the first wall portion 321 and the other end of the power storage stack 20 compared to the second end plate 32 according to the embodiment. A plate-like portion 323 is provided as shown in FIG. In the power storage stack cooling structure 10X including the second end plate 32X, the gap S2 between the first wall portion 321 and the other end of the power storage stack 20 does not communicate with the coolant supply path 6 .

FIG. 12 is a diagram showing the temperature distribution of the power storage stack according to the comparative example. The temperature distribution of the power storage stack according to the comparative example will be described with reference to FIG. 12 . Note that the scales of the vertical and horizontal axes in FIG. 12 are substantially the same as those in FIG.

As shown in FIG. 12 , also in the comparative example, the power storage stack 20 has a plurality of power storage cells arranged side by side. As described above, the gap S1 between the first opposing wall portion 311 and one end of the electricity storage stack 20 does not communicate with the coolant supply path 6, and the gap S1 between the first wall portion 321 and the other end of the electricity storage stack 20 does not communicate. When the gap S2 does not communicate with the coolant supply path 6, only one side of the pair of side surfaces opposed to each other in the arrangement direction is cooled in the unit cells positioned at both ends in the arrangement direction. In other single cells, both of the pair of side portions are cooled.

Therefore, the energy storage stack 20 has a temperature distribution in which the temperature of the energy storage cells arranged at both ends in the arrangement direction is high. In addition, there is a temperature difference between the highest storage cell temperature and the lowest storage cell temperature, and the temperature variation is greater than in the embodiment.

Furthermore, since the temperature of the storage cells arranged at both ends in the arrangement direction becomes high, even if the temperature of the storage cells on one side is controlled, it is difficult to control the temperature of the storage cells on the other side. Become. Therefore, a plurality of thermometers must be used to manage the temperatures of both storage cells, making it difficult to manage the temperature of the storage stack 20 .

As described above, the comparison between the embodiment and the comparative example also shows that the cooling structure 10 for the electricity storage stack according to the embodiment suppresses the temperature variation of the electricity storage stack 20 as described above. In addition, it can be said that temperature control of the electricity storage stack can be easily performed.

In the above-described embodiment, the inlet areas of the first path 61, the second path 62, and the third path 63 are appropriately adjusted so that the refrigerant is less likely to enter the third path 63 than the second path 62. However, it is not limited to this, and the rib height of the second end plate 32 is set lower than the rib height of the first end plate 31, or the rib width of the second end plate 32 is set lower than that of the first end plate 31. may be thickened to make the volume of the third path 63 smaller than the volume of the second path 62 .

As described above, the embodiments disclosed this time are illustrative in all respects and are not restrictive. The scope of the present invention is indicated by the scope of claims, and includes all modifications within the meaning and scope of equivalence to the scope of claims.

REFERENCE SIGNS LIST 1 vehicle 2 power storage module 3 accommodation case 3a bottom 4 coolant duct 4a tip 4b stopper 5 coolant supply source 6 coolant supply path 10, 10X power storage stack cooling structure 20 power storage stack 21 power storage cell , 22 spacer, 31, 31X first end plate, 31a bracket part, 31b fixing part, 32, 32X second end plate, 32a bracket part, 32b fixing part, 40 restraint member, 41 insertion part, 50 control part, 51 temperature total, 61 first path, 62 second path, 63 third path, 100 cooling system, 310 body portion, 311 first opposing wall portion, 311a front surface, 311b, 321b back surface, 312 second opposing wall portion, 313 opening, 314 protrusion, 315 rib, 320 main body, 321 first wall, 321a front surface, 321b rear surface, 322 second wall, 323 plate-like portion, 325 rib, 3151, 3152 rib.

Claims (3)

an electricity storage stack including a plurality of electricity storage cells arranged in a predetermined arrangement direction;
a first end plate and a second end plate arranged on both outer sides of the power storage stack in the arrangement direction;
a coolant supply path provided along the arrangement direction for supplying a coolant from one end side to the other end side of the electricity storage stack in the arrangement direction;
a plurality of first paths respectively provided in gaps between the two adjacent energy storage cells and communicating with the coolant supply path;
The first end plate is configured such that a second path communicating with the coolant supply path is formed in a gap between the first end plate and the one end of the electricity storage stack,
The second end plate is configured such that a third path communicating with the coolant supply path is formed in a gap between the second end plate and the other end of the electricity storage stack,
The plurality of first paths, the second path, and the third path are configured such that when the refrigerant cools the electricity storage stack, the temperature of the electricity storage cell arranged on the one end side is lower than the temperature on the other end side. The electricity storage stack is configured to have a temperature distribution in which the temperature of the arranged electricity storage cells increases ,
the entrance area of the third path is smaller than the entrance area of the second path;
The first end plate is connected to a first opposing wall portion facing the one end of the power storage stack, and connected to the first opposing wall portion to supply the refrigerant supply path to the power storage cell positioned at the one end of the power storage stack. a second opposing wall portion facing from the side,
The second opposing wall portion is provided with an opening for communicating a gap between the first opposing wall portion and the one end of the electricity storage stack and the coolant supply path,
the second end plate includes a third facing wall facing the other end of the electricity storage stack;
The third opposing wall portion is connected to the first wall portion and the first wall portion on the coolant supply path side, and is closer to the other end side of the power storage stack than the first wall portion in the arrangement direction. and a second wall provided to
a gap between the first wall portion and the other end of the power storage stack communicates with the coolant supply path through the gap between the second wall portion and the other end of the power storage stack;
The power storage stack cooling structure , wherein a distance between the second wall portion and the other end of the power storage stack in the arrangement direction is shorter than a width of the opening in the arrangement direction . further comprising a coolant duct inserted into one end side of the coolant supply path where the first end plate is located;
The first end plate has a protruding portion that protrudes in a direction opposite to the direction in which the refrigerant duct is inserted,
2. The power storage stack cooling structure according to claim 1 , wherein said refrigerant duct has a stopper provided so as to be able to abut against said projecting portion so that a tip of said refrigerant duct does not block an inlet portion of said second path. a cooling structure for an electricity storage stack according to claim 1 or 2 ;
a coolant supply source that supplies the coolant to the coolant supply path;
a control unit that controls the operation of the coolant supply source;
a thermometer that measures the temperature of the storage cell located at the other end of the storage stack,
A cooling system for a power storage stack, wherein the control unit controls the operation of the coolant supply source so that the supply amount of the coolant increases when the temperature measured by the thermometer reaches or exceeds a predetermined temperature.

Images