JP7273495B2 - power storage device - Google Patents

Description

The present invention relates to a power storage device.

Patent Literature 1 describes a so-called bipolar power storage module that includes a bipolar electrode having a positive electrode provided on one side of an electrode plate and a negative electrode provided on the other side.

JP 2011-204386 A

It is conceivable that a power storage device is configured by stacking a plurality of power storage modules described above. In such a power storage device, in order to cool the power storage modules, a flow path member provided with a plurality of flow paths for flowing a coolant such as air is sometimes interposed, for example, between adjacent power storage modules. However, there are cases in which the coolant tends to circulate unevenly in the flow paths provided in some regions among the plurality of flow paths in the flow path member. It is conceivable that there is a large variation in each

An object of the present invention is to provide a power storage device capable of suppressing position-to-position variations in cooling performance.

A power storage device according to the present invention includes a power storage module and a cooling mechanism for cooling the power storage module, wherein the cooling mechanism extends along a first direction and crosses the first direction. a flow path member having a plurality of coolant flow paths arranged along two directions; an introduction duct through which the coolant flows so as to introduce the coolant into the channel; a lead-out duct for circulating the refrigerant led out from the lead-out duct, the lead-in duct is provided with an inlet for introducing the coolant into the lead-out duct, and the lead-out duct is provided with the coolant from the lead-out duct. An outlet is provided for leading out, the inlet and the outlet are located on one end side of the flow path member in the second direction, and the flow path member is positioned in the second direction of the flow path member. It is configured such that the pressure loss when the coolant passes through the coolant channel gradually decreases toward the other end.

In the power storage device according to the present invention, the plurality of refrigerant flow paths formed in the flow path member are arranged along the second direction, and the inlet of the introduction duct and the outlet of the outlet duct are arranged in the second direction of the flow path member. It is located on one end side of the direction. In such a configuration, when the flow path member is uniformly configured along the second direction, the coolant flows through the coolant flow path formed in the region on the one end side of the plurality of coolant flow paths in the flow path member. It is easy to distribute biased to. On the other hand, in the power storage device according to the present invention, the pressure loss when the coolant passes through the coolant flow channel gradually decreases as the flow channel member moves toward the other end of the flow channel member in the second direction. is configured to be Therefore, the coolant can easily flow through the coolant channel located on the other end side of the channel member according to the pressure loss. Therefore, it is possible to suppress uneven distribution of the coolant among the plurality of coolant channels in the channel member, and to suppress variations in cooling performance between positions.

Further, in the power storage device according to the present invention, the cooling mechanism may include a blower connected to the outlet and sucking the coolant so as to discharge the coolant from the outlet duct. In this case, the refrigerant can be circulated through the introduction duct, the plurality of refrigerant flow paths, and the flow path extending through the outlet duct by a configuration (a so-called pull system) in which the refrigerant is sucked from the outlet by the blower. As a result, the coolant can be efficiently circulated, for example, compared to a configuration that does not have a blower or a configuration that supplies the coolant to the inlet using a blower (so-called push system).

Further, in the power storage device according to the present invention, the flow path member is arranged in accordance with a change in the area of the cross section intersecting the first direction of the refrigerant flow path toward the other end of the flow path member in the second direction. It may be configured such that the pressure loss decreases stepwise. In this case, the pressure loss difference can be easily configured by changing the area.

Further, in the power storage device according to the present invention, the channel member includes a plurality of cooling plates arranged along the second direction, each of which is formed with a part of the plurality of coolant channels. and the area of the coolant channel may be different for each cooling plate. In this case, since a single cooling plate can share a plurality of coolant passages, it is possible to form a passage member using a plurality of types of cooling plates each having a simple configuration.

Further, in the power storage device according to the present invention, the change in area may be defined by the interval between the walls forming the coolant flow path. In this case, the area of the channel can be changed with a simple configuration.

Moreover, in the power storage device according to the present invention, the interval between the wall portions may be defined by the width of the wall portion along the second direction. In this case, the space between the walls can be changed with a simple configuration.

In addition, in the power storage device according to the present invention, the refrigerant channel has convex portions formed therein, and the channel member is arranged at the other end of the channel member in the second direction according to the formation density of the convex portions. It may be configured such that the pressure loss decreases stepwise toward the part. In this case, it is easy to finely adjust the pressure loss by changing the formation density of the convex portions.

Further, in the power storage device according to the present invention, the coolant channel is formed in a tapered shape that narrows from one end of the channel member toward the other end in the first direction. The pressure loss may decrease stepwise toward the other end of the flow path member in the second direction according to the reduction ratio of the flow path member. In this case, along with suppressing variation in cooling performance for each position along the second direction of the flow path member, variation in cooling performance for each position along the first direction of the flow path member can also be suppressed.

ADVANTAGE OF THE INVENTION According to this invention, the electrical storage apparatus which can suppress the dispersion|variation in cooling performance for every position can be provided.

FIG. 1 is a schematic cross-sectional view showing one embodiment of a power storage device. 2 is a schematic cross-sectional view showing the internal configuration of the power storage module shown in FIG. 1. FIG. FIG. 3(a) is a sectional view taken along line IIIA-IIIA in FIG. FIG. 3(b) is a sectional view along line IIIB-IIIB in FIG. 3(a). FIG. 4 is a cross-sectional view showing a cooling mechanism according to a comparative example. FIG. 5 is a diagram showing a pressure distribution state of a cooling mechanism according to a comparative example. FIG. 6 is a diagram showing the pressure distribution state of the cooling mechanism according to this embodiment. FIG. 7 is a cross-sectional view showing a cooling member according to a modification. FIG. 8 is a cross-sectional view showing a cooling member according to a modification.

An embodiment will be described below with reference to the drawings. In the description of the drawings, the same elements or corresponding elements are denoted by the same reference numerals, and redundant description may be omitted. Also shown in the following figures is a Cartesian coordinate system S defined by an X-axis, a Y-axis and a Z-axis.

First, the configuration of a power storage device according to one embodiment will be described. FIG. 1 is a schematic cross-sectional view showing one embodiment of a power storage device. A power storage device 10 shown in FIG. 1 is used, for example, as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The power storage device 10 includes a plurality (three in the present embodiment) of power storage modules 12 stacked on each other, a cooling mechanism 13 including a plurality (four in the present embodiment) of cooling members 14 (flow path members), and a restraint module. a member 15; Note that the power storage device 10 may include at least one power storage module 12 and a cooling mechanism 13 including at least one cooling member 14 .

The power storage module 12 is, for example, a bipolar battery having a rectangular plate shape and including a plurality of bipolar electrodes (bipolar electrodes 32 to be described later). The storage module 12 is, for example, a secondary battery such as a nickel-hydrogen secondary battery or a lithium-ion secondary battery, but may be an electric double layer capacitor. In the following description, a nickel-metal hydride secondary battery is exemplified.

Cooling member 14 cools power storage module 12 by circulating a coolant. The cooling member 14 is made of a conductive material such as metal, and has electrical conductivity. The cooling member 14 is stacked together with the power storage modules 12 and electrically connected to the power storage modules 12 adjacent to each other along the stacking direction (here, the Z direction). Thereby, the plurality of power storage modules 12 are connected in series in the stacking direction. The cooling members 14 are arranged between the power storage modules 12 adjacent in the stacking direction and outside the power storage modules 12 positioned at the stack end. A positive electrode terminal 24 is connected to one cooling member 14 arranged outside the power storage module 12 positioned at the end of the stack. A negative electrode terminal 26 is connected to the other cooling member 14 arranged outside the power storage module 12 positioned at the end of the stack. The positive terminal 24 and the negative terminal 26 are pulled out, for example, from the edge of the cooling member 14 in a direction intersecting the stacking direction (here, the X direction). Charging and discharging of the power storage device 10 are performed by the positive terminal 24 and the negative terminal 26 .

In the example of FIG. 1, the area of the cooling member 14 when viewed in the stacking direction is smaller than the area of the storage module 12, but from the viewpoint of improving heat dissipation, the area of the cooling member 14 is equal to the area of the storage module 12. , or may be larger than the area of the power storage module 12 .

The binding member 15 applies a binding load to the plurality of power storage modules 12 . The restraint member 15 has a pair of end plates 16 and 17 (restraint plates) and a fastening member including a plurality of restraint bolts 18 and a plurality of nuts 20 . A pair of end plates 16 and 17 are arranged to sandwich the plurality of power storage modules 12 and the plurality of cooling members 14 along the stacking direction. The end plates 16 and 17 are rectangular metal plates having an area slightly larger than the area of the power storage module 12 and the cooling member 14 when viewed in the stacking direction. Insertion holes 16 a and 17 a are provided in the edge portions of the end plates 16 and 17 at positions outside the power storage module 12 . A film 22 having electrical insulation is provided on the inner surfaces (surfaces on the cooling member 14 side) of the end plates 16 and 17 . Film 22 provides insulation between end plates 16 and 17 and cooling member 14 .

Each restraint bolt 18 is passed from the insertion hole 16a of one end plate 16 toward the insertion hole 17a of the other end plate 17, and the tip portion of each restraint bolt 18 protruding from the insertion hole 17a of the other end plate 17. A nut 20 is screwed on. As a result, the plurality of power storage modules 12 and the plurality of cooling members 14 are sandwiched between the end plates 16 and 17 to form a unit, and a binding load is applied to the plurality of power storage modules 12 in the stacking direction.

Next, the configuration of the power storage module 12 will be described in more detail. 2 is a schematic cross-sectional view showing the internal configuration of the power storage module shown in FIG. 1. FIG. As shown in FIG. 2 , the power storage module 12 includes an electrode laminate 30 and a resin sealing member 50 that seals the electrode laminate 30 .

The electrode laminate 30 is formed by laminating a plurality of bipolar electrodes 32 with separators 40 interposed therebetween. In this example, the stacking direction D of the electrode stack 30 is the Z direction. That is, the stacking direction D matches the stacking direction of the power storage modules 12 . The bipolar electrode 32 includes an electrode plate 34 , a positive electrode 36 provided on one surface 34 s of the electrode plate 34 , and a negative electrode 38 provided on the other surface 34 r of the electrode plate 34 . The positive electrode 36 is a positive electrode active material layer coated with a positive electrode active material. The negative electrode 38 is a negative electrode active material layer coated with a negative electrode active material. In the electrode stack 30 , the positive electrode 36 of one bipolar electrode 32 faces the negative electrode 38 of one bipolar electrode 32 adjacent along the stacking direction D with the separator 40 interposed therebetween. In the electrode stack 30 , the negative electrode 38 of one bipolar electrode 32 faces the positive electrode 36 of the other bipolar electrode 32 adjacent along the stacking direction D with the separator 40 interposed therebetween.

In the electrode laminate 30 , a negative terminal electrode 42 is arranged at one end in the stacking direction D, and a positive terminal electrode 44 is arranged at the other end in the stacking direction D. The negative terminal electrode 42 includes an electrode plate 34 and a negative electrode 38 provided on the other surface 34 r of the electrode plate 34 . The negative electrode 38 of the negative terminal electrode 42 faces the positive electrode 36 of the bipolar electrode 32 at one end in the stacking direction D with the separator 40 interposed therebetween. One surface 34 s of the electrode plate 34 of the negative terminal electrode 42 is in contact with one cooling member 14 adjacent to the power storage module 12 . The positive terminal electrode 44 includes an electrode plate 34 and a positive electrode 36 provided on one surface 34 s of the electrode plate 34 . The other cooling member 14 adjacent to the power storage module 12 is in contact with the other surface 34 r of the electrode plate 34 of the positive terminal electrode 44 . The positive electrode 36 of the positive terminal electrode 44 faces the negative electrode 38 of the bipolar electrode 32 at the other end in the stacking direction D with the separator 40 interposed therebetween.

The electrode plate 34 is made of metal, such as nickel or a nickel-plated steel plate. The electrode plate 34 is a rectangular metal foil made of nickel, for example. A peripheral edge portion 34a of the electrode plate 34 has a rectangular frame shape and is an uncoated region where the positive electrode active material and the negative electrode active material are not coated. Examples of the positive electrode active material forming the positive electrode 36 include nickel hydroxide. Examples of the negative electrode active material forming the negative electrode 38 include hydrogen storage alloys. In this embodiment, the formation area of the negative electrode 38 on the other surface 34r of the electrode plate 34 is one size larger than the formation area of the positive electrode 36 on the one surface 34s of the electrode plate 34 .

The separator 40 is formed in a sheet shape, for example. Examples of the separator 40 include porous films made of polyolefin resins such as polyethylene (PE) and polypropylene (PP), and woven or nonwoven fabrics made of polypropylene, methyl cellulose, and the like. The separator 40 may be reinforced with a vinylidene fluoride resin compound. Note that the separator 40 is not limited to a sheet shape, and may be bag-shaped.

The sealing member 50 is formed in a rectangular frame shape, for example, from an insulating resin. Examples of the resin material forming the sealing member 50 include polypropylene (PP), polyphenylene sulfide (PPS), modified polyphenylene ether (modified PPE), and the like. The sealing member 50 surrounds the electrode laminate 30 and is configured to hold the peripheral edge portions 34 a of the plurality of electrode plates 34 .

The seal member 50 has a primary seal 52 provided on the peripheral portion 34 a and a secondary seal 54 provided around the primary seal 52 . The primary seal 52 is a film having a predetermined thickness (length along the stacking direction D). The primary seal 52 has a rectangular frame shape when viewed from the stacking direction D, and is continuously welded over the entire circumference of the peripheral portion 34a by, for example, ultrasonic waves or heat. The primary seal 52 is provided on the peripheral edge portion 34 a in a state where the peripheral edge portion 34 a is embedded, and covers the end surface of the electrode plate 34 . The primary seal 52 is provided apart from the positive electrode 36 and the negative electrode 38 when viewed in the stacking direction D. As shown in FIG. The primary seals 52 adjacent to each other along the stacking direction D may be in contact with each other, or may be separated from each other.

The secondary seal 54 is provided outside the electrode laminate 30 and the primary seal 52 and constitutes an outer wall (housing) of the power storage module 12 . The secondary seal 54 is formed, for example, by injection molding of resin, and extends over the entire length of the electrode laminate 30 in the lamination direction D. As shown in FIG. The secondary seal 54 has a tubular shape (frame shape) extending along the stacking direction D. As shown in FIG. The secondary seal 54 covers the outer surface of the primary seal 52 along the stacking direction D. As shown in FIG. A secondary seal 54 is joined to the outer surface of the primary seal 52 and seals the outer surface of the primary seal 52 . The secondary seal 54 is welded to the outer surface of the primary seal 52 by heat during injection molding, for example. The secondary seal 54 may be welded to the outer surface of the primary seal 52 by hot plate welding.

Between the electrode plates 34 adjacent to each other along the stacking direction D, an internal space V partitioned airtight and watertight by the electrode plates 34 and the sealing member 50 is formed. In other words, one internal space V is defined by a pair of electrode plates 34 adjacent to each other along the stacking direction D. As shown in FIG. Below, a portion including a pair of electrode plates 34 adjacent to each other along the stacking direction D and one internal space V defined by the pair of electrode plates 34 may be referred to as a power storage cell 39 .

The internal space V accommodates an electrolytic solution (not shown) composed of, for example, an alkaline aqueous solution such as an aqueous potassium hydroxide solution. That is, the power storage module 12 includes a plurality of power storage cells 39 that are stacked one on top of the other, and an electrolytic solution placed in the internal space V of each of the power storage cells 39 . The electrolytic solution is impregnated in the separator 40 , the positive electrode 36 and the negative electrode 38 . Since the electrolytic solution is strongly alkaline, the sealing member 50 is made of a resin material having strong alkali resistance.

Next, a detailed configuration of the cooling mechanism 13 for cooling the power storage module 12 will be described. FIG. 3(a) is a sectional view taken along line IIIA-IIIA in FIG. FIG. 3(b) is a sectional view along line IIIB-IIIB in FIG. 3(a). In addition, illustration of the electrical storage module 12 and the binding member 15 is abbreviate|omitted in Fig.3 (a). As shown in FIGS. 3A and 3B, the cooling mechanism 13 includes the cooling member 14 described above, an introduction duct 61, an extraction duct 62, and a blower 63. As shown in FIG.

Cooling member 14 releases heat generated in power storage module 12 (see FIG. 1 ) to the outside by circulating a coolant inside cooling member 14 , thereby cooling power storage module 12 . That is, the cooling member 14 has a function as a connection member that electrically connects the power storage modules 12 together, and also a function as a radiator plate that dissipates heat generated in the power storage modules 12 . The coolant has, for example, insulating properties, and is air, gas such as ammonia, or liquid such as LLC.

The cooling member 14 has a rectangular plate shape and is arranged such that the thickness direction thereof is along the stacking direction (that is, the Z direction) of the power storage modules 12 . The cooling member 14 has a pair of main surfaces 14s intersecting (perpendicular to) the stacking direction. Each main surface 14s has an elongated shape with one direction (here, the X direction) as the longitudinal direction. Each main surface 14s faces the power storage module 12 along the stacking direction and constitutes a cooling surface that is thermally connected to the power storage module 12 (for example, contacts the power storage module 12). In this embodiment, the entire main surface 14s constitutes a cooling surface.

The cooling member 14 is formed with a plurality of coolant passages 64 for circulating the coolant along the main surface 14s. The plurality of coolant channels 64 linearly extend in a first direction (here, the Y direction) and are arranged along a second direction (here, the X direction) intersecting the first direction. In this embodiment, the arrangement direction of the plurality of coolant flow paths 64 and the longitudinal direction of the main surface 14s of the cooling member 14 match. The multiple coolant channels 64 are parallel to each other. A cross section of the coolant channel 64 that intersects (perpendicularly) with the first direction (hereinafter referred to as a "channel cross section") is rectangular in the illustrated example, but may be other shapes such as a circle. The cross-sectional area of each coolant channel 64 (hereinafter referred to as "channel area") is constant along the first direction, for example.

The cooling member 14 is configured such that the pressure loss when the coolant passes through the coolant channel 64 decreases stepwise from the one end 14a toward the other end 14b of the cooling member 14 in the second direction. there is Specifically, the cooling member 14 shown in FIG. 3 is configured such that the pressure loss gradually decreases toward the other end portion 14b according to changes in the flow area of the coolant flow path 64. . Here, the flow area of the coolant flow path 64 increases stepwise from the one end 14a toward the other end 14b.

More specifically, the cooling member 14 has a plurality of (for example, four) cooling plates 65 in which coolant channels 64 different from each other are formed. A part of the plurality of coolant channels 64 in one cooling member 14 is formed in each of the plurality of cooling plates 65 . Although a plurality of coolant channels 64 are formed in one cooling plate 65 in the drawing, only one coolant channel 64 may be formed in one cooling plate 65 . When a plurality of coolant flow paths 64 are formed in one cooling plate 65, the plurality of coolant flow paths 64 formed in a common cooling plate 65 have the same configuration.

A plurality of cooling plates 65 are arranged along the second direction. Thus, the plurality of cooling plates 65 constitute the cooling member 14 as a whole. One main surface 14 s (cooling surface) is composed of a plurality of cooling plates 65 . The flow area of the coolant flow path 64 is different for each cooling plate 65 . The plurality of cooling plates 65 are arranged from one end portion 14a toward the other end portion 14b in ascending order of passage area.

Each cooling plate 65 includes a pair of flat plate portions 65a and a plurality of wall portions 65b connecting the pair of flat plate portions 65a to each other. Each flat plate portion 65a has a flat plate shape that intersects the stacking direction of the power storage module 12 (that is, a flat plate shape extending along the first direction and the second direction), and constitutes a part of the main surface 14s. The plurality of wall portions 65b extend along the first direction and are arranged apart from each other along the second direction. Thereby, the coolant channel 64 is formed so as to be surrounded by the flat plate portion 65a and the wall portion 65b. Also, the change in the flow area of the coolant channel 64 is defined by the interval C between the wall portions 65b forming the coolant channel 64 . The interval C increases stepwise from the one end 14a toward the other end 14b. Further, in the present embodiment, the center-to-center distance L between the wall portions 65b adjacent to each other along the second direction is constant. The interval C is defined by the width B along the second direction of each wall portion 65b. The width B decreases stepwise from the one end portion 14a toward the other end portion 14b.

Note that the width B may be constant and the interval C may be defined by the center-to-center distance L. That is, the center-to-center distance L may decrease stepwise from the one end 14a toward the other end 14b. Alternatively, the spacing C may be defined by both the width B and the center-to-center distance L.

The introduction duct 61 circulates the coolant so as to introduce the coolant to each of the coolant channels 64 . The introduction duct 61 is provided so as to extend along the second direction with respect to the one end portion 14c of the cooling member 14 in the first direction. The length of the introduction duct 61 along the second direction is longer than the entire length of the cooling member 14 along the second direction. As an example, the introduction duct 61 is formed in a tapered shape that narrows from the one end 14a of the cooling member 14 toward the other end 14b. All coolant channels 64 of the cooling member 14 communicate with the introduction duct 61 . The introduction duct 61 may be formed over the entire length of the stacking height H (see FIG. 1) of the power storage modules 12 and the cooling member 14 that are stacked together. That is, the introduction duct 61 may communicate with the coolant flow paths 64 of all the cooling members 14 .

The introduction duct 61 is provided with an introduction port 61 a for introducing the refrigerant into the introduction duct 61 . The introduction port 61a is positioned on the one end portion 14a side of the cooling member 14 . Specifically, the introduction port 61a is provided at a position that protrudes in the second direction from the one end portion 14a.

The lead-out duct 62 allows the coolant led out from each coolant channel 64 to circulate. Lead-out duct 62 is provided to extend along the second direction with respect to the other end portion 14d of cooling member 14 in the first direction. The length of lead-out duct 62 along the second direction is longer than the entire length of cooling member 14 along the second direction. As an example, the lead-out duct 62 is formed in a tapered shape that narrows from the one end 14a of the cooling member 14 toward the other end 14b. All coolant channels 64 of the cooling member 14 communicate with the lead-out duct 62 . The lead-out duct 62 may be formed over the entire length of the stacking height H (see FIG. 1) of the power storage modules 12 and the cooling member 14 that are stacked together. That is, the outlet duct 62 may communicate with the coolant flow paths 64 of all the cooling members 14 .

The lead-out duct 62 is provided with a lead-out port 62 a for leading the coolant from the lead-out duct 62 . The outlet port 62a is located on the one end portion 14a side of the cooling member 14 . Specifically, the outlet port 62a is provided at a position that protrudes in the second direction from the one end portion 14a.

The blower 63 is connected to the outlet 62a. The blower 63 sucks the refrigerant inside the outlet duct 62 through the outlet 62a and discharges the refrigerant from the outlet duct 62 to the outside. In addition, when the blower 63 sucks the refrigerant from the outlet port 62a, the external refrigerant is sucked into the inlet duct 61 from the inlet port 61a, and the refrigerant flows through the inlet duct 61, the plurality of refrigerant flow paths 64, and the outlet duct. 62 distributed.

The effects of power storage device 10 described above will be described. FIG. 4 is a cross-sectional view showing a cooling mechanism according to a comparative example. 4A shows a cross section corresponding to FIG. 3A, and FIG. 4B shows a cross section corresponding to FIG. ing. The cooling mechanism 13X shown in FIG. 4 is different from the cooling mechanism 13 according to the present embodiment in that the pressure loss along the second direction of the cooling member 14 is constant, and is otherwise similar to the cooling mechanism 13. It is configured. Specifically, in the cooling mechanism 13X, the plurality of coolant channels 64 formed in the cooling member 14 have the same channel area.

FIG. 5 is a diagram showing a pressure distribution state of a cooling mechanism according to a comparative example. FIG. 6 is a diagram showing the pressure distribution state of the cooling mechanism according to this embodiment. In FIGS. 5 and 6, the pressure is indicated by contour lines, and the darker the color, the higher the pressure. In the cooling mechanisms 13 and 13X, the refrigerant flows more easily in the portions where the intervals between the pressure contour lines are narrower, and the refrigerant flows more difficultly in the portions where the intervals between the pressure contour lines are wider.

In the power storage device 10 according to the present embodiment, the plurality of coolant flow paths 64 formed in the cooling member 14 are arranged along the second direction (here, the X direction), and the introduction port 61a of the introduction duct 61 and the outlet duct An outlet port 62a of 62 is located on the side of one end portion 14a of the cooling member 14 in the second direction. Accordingly, compared to a configuration in which either one of the inlet 61a and the outlet 62a is located on the other end 14b side in the second direction, the power storage device 10 can be made compact. On the other hand, in such a configuration, when the cooling member 14 is uniformly configured along the second direction like the cooling mechanism 13X, as shown in FIG. The interval between the contour lines is extremely narrow in the area of , and the interval between the contour lines is wide in the area on the other end portion 14b side of the cooling member 14 . In other words, the coolant tends to flow unevenly in the coolant channel 64 formed in the region on the one end portion 14 a side among the plurality of coolant channels 64 in the cooling member 14 .

On the other hand, in the cooling mechanism 13 of the power storage device 10 according to the present embodiment, the cooling member 14 moves toward the other end 14b of the cooling member 14 in the second direction when the coolant passes through the coolant channel 64. is configured so that the pressure loss of is gradually reduced. Therefore, as shown in FIG. 6, the intervals between the contour lines are substantially uniform over the entire cooling member 14 . In other words, the coolant can easily flow through the coolant channel 64 located on the other end 14b side of the cooling member 14 according to the pressure loss. Therefore, uneven distribution of the coolant among the plurality of coolant passages 64 in the cooling member 14 is suppressed, and it is possible to suppress variations in cooling performance for each position.

In the power storage device 10 , the cooling mechanism 13 has a blower 63 that is connected to the outlet port 62 a and sucks the refrigerant so as to discharge the refrigerant from the outlet duct 62 . As a result, the refrigerant can be circulated through the flow path including the introduction duct 61 , the plurality of refrigerant flow paths 64 , and the discharge duct 62 by a configuration (a so-called pull system) in which the refrigerant is sucked from the outlet 62 a by the blower 63 . For this reason, the refrigerant can be efficiently circulated, for example, compared to a configuration that does not have the blower 63 or a configuration that supplies the refrigerant to the introduction port 61a by the blower 63 (so-called push method).

In the power storage device 10, the cooling member 14 changes according to the change in the flow area of the coolant flow path 64 (that is, the area of the cross section intersecting the first direction (here, the Y direction)). The pressure loss is configured to decrease stepwise toward the other end 14b in the second direction. Thereby, it is easy to configure the difference in pressure loss simply by changing the flow path area.

In power storage device 10 , cooling member 14 has a plurality of cooling plates 65 arranged along the second direction, in which part of coolant channels 64 of the plurality of coolant channels 64 are formed. The flow area of the coolant flow path 64 is different for each cooling plate 65 . As a result, a single cooling plate 65 can share the configuration of a plurality of coolant channels 64, so that the cooling member 14 can be formed using a plurality of types of cooling plates 65 each having a simple configuration. can.

Further, in power storage device 10 , the change in flow path area is defined by interval C between wall portions 65 b forming coolant flow path 64 . This makes it possible to change the flow channel area with a simple configuration.

In power storage device 10, interval C between wall portions 65b is defined by width B of wall portions 65b along the second direction. Thereby, the interval C can be changed with a simple configuration.

The above embodiment describes one embodiment of the power storage device according to the present invention. The power storage device according to the present invention can be an arbitrary modification of the power storage device 10 described above.

For example, in the above-described embodiment, the cooling member 14 is configured such that the pressure loss gradually decreases toward the other end portion 14b according to the change in the flow area of the coolant flow path 64 . However, the configuration of the cooling member 14 for adjusting pressure loss is not limited to this. 7 and 8 are cross-sectional views showing cooling members according to modifications.

As shown in FIG. 7, the interval C of the wall portion 65b of the cooling member 14 may be constant, and the flow area of the coolant flow path 64 formed so as to be surrounded by the flat plate portion 65a and the wall portion 65b is They may be the same as each other. In the cooling member 14 shown in FIG. 7 , a plurality of protrusions 66 are formed inside the coolant channel 64 . In other words, the flow area of the coolant flow path 64 at the position where the projections 66 are formed is larger than the flow area surrounded by the flat plate portion 65a and the wall portion 65b depending on the formation density of the projections 66. narrow.

The cooling member 14 shown in FIG. 7 is configured such that the pressure loss gradually decreases toward the other end portion 14b according to the formation density of the convex portions 66. As shown in FIG. In the cooling member 14 according to this modified example, the formation density of the convex portions 66 formed in the coolant flow path 64 decreases stepwise from the one end portion 14a toward the other end portion 14b. With this configuration, it is easy to finely adjust the pressure loss by changing the formation density of the convex portions 66 . The formation density of the protrusions 66 formed in the coolant flow path 64 may be zero at the side of the cooling member 14 closest to the other end 14b. For example, the protrusions 66 may not be formed in the plurality of coolant channels 64 formed in the cooling plate 65 arranged closest to the one end 14a. The formation density of the protrusions 66 can be adjusted by, for example, the number, size, or fineness of the protrusions 66 .

Also, a concave portion (not shown) may be formed inside the coolant channel 64 instead of the convex portion 66 . In this case, the cooling member 14 is configured such that the pressure loss gradually decreases toward the other end portion 14b according to the formation density of the recesses. Specifically, the formation density of the recesses formed in the coolant channel 64 increases stepwise from the one end portion 14a toward the other end portion 14b. Alternatively, both the convex portion 66 and the concave portion may be formed inside the coolant channel 64 . In this case, the cooling member 14 is configured such that the pressure loss gradually decreases toward the other end portion 14b according to the formation density of the convex portions 66 and the concave portions.

Further, as shown in FIG. 8, the coolant flow path 64 may be formed in a tapered shape that narrows from the one end 14c of the cooling member 14 toward the other end 14d. In this case, the cooling member 14 is configured such that the pressure loss gradually decreases toward the other end portion 14 b according to the contraction rate of the coolant flow path 64 . Here, the reduction ratio is the ratio of the reduced area (difference between the channel area at one end 14c and the channel area at the other end 14d) to the original area (channel area at one end 14c). In the cooling member 14 according to this modified example, the contraction rate of the coolant channel 64 decreases stepwise from the one end portion 14a toward the other end portion 14b. With this configuration, it is possible to suppress variation in cooling performance for each position along the second direction of the cooling member 14 and suppress variation in cooling performance for each position along the first direction of the cooling member 14 . Note that the contraction ratio of the coolant flow path 64 may be zero at the side of the cooling member 14 closest to the one end portion 14a. For example, the plurality of coolant channels 64 formed in the cooling plate 65 arranged closest to the one end portion 14a may not have a tapered shape.

Also, the configuration of the cooling member 14 for adjusting the pressure loss may be an arbitrary combination of the configurations in the above-described embodiment and modifications. For example, the cooling member 14 is controlled by changes in the flow channel area (the cross-sectional area of the coolant flow channel 64 intersecting the first direction), the formation density of the convex portions 66, and the reduction ratio of the coolant flow channel 64 (in the first direction The pressure loss increases stepwise from the one end 14a of the cooling member 14 toward the other end 14b according to a combination of at least two or more of the tapered coolant passages 64 that shrink along the may be configured to be smaller than

In addition, the change in the flow area of the coolant channel 64 may be defined by the formation density of the protrusions 66 or the reduction rate of the coolant channels 64 . It may be defined by a combination of at least two or more of the ratio and the interval C of the wall portion 65b described above.

Further, the interval C between the wall portions 65b may be defined by the formation density of the convex portions 66 or the reduction rate of the coolant flow paths 64, and the formation density of the convex portions 66, the reduction rate of the coolant flow paths 64, and It may be defined by a combination of at least two or more of the widths B along the second direction of the wall portion 65b described above.

DESCRIPTION OF SYMBOLS 10... Power storage apparatus 12... Power storage module 13... Cooling mechanism 14... Cooling member (flow path member) 14a, 14c... One end 14b, 14d... Other end 61... Introduction duct 61a... Introduction port, 62... Lead-out duct, 62a... Lead-out port, 63... Blower, 64... Refrigerant channel, 65... Cooling plate, 65b... Wall part, 66... Convex part, B... Width, C... Spacing.

Claims (6)

A power storage device comprising a plurality of stacked power storage modules and a cooling mechanism for cooling the power storage modules,
The cooling mechanism is
A channel member formed with a plurality of coolant channels extending along a first direction intersecting the stacking direction of the power storage modules and arranged along a second direction intersecting the first direction and the stacking direction. and,
An introduction duct provided to extend along the second direction at one end portion of the flow channel member in the first direction and for introducing the coolant into each of the coolant flow channels. and,
a lead-out duct provided so as to extend along the second direction with respect to the other end portion of the flow path member in the first direction, and for circulating the coolant led out from each of the coolant flow paths. death,
The introduction duct is provided with an introduction port for introducing the refrigerant into the introduction duct,
The lead-out duct is provided with an outlet for leading the refrigerant from the lead-out duct,
The inlet and the outlet are located on one end side of the flow path member in the second direction,
The flow path member is configured such that pressure loss when the refrigerant passes through the refrigerant flow path gradually decreases toward the other end of the flow path member in the second direction,
In the flow path member, the pressure loss increases stepwise toward the other end of the flow path member in the second direction according to a change in the cross-sectional area of the refrigerant flow path that intersects the first direction. is configured to be as small as
The change in the area is defined by the spacing of the walls forming the coolant channel,
storage device. The cooling mechanism has a blower connected to the outlet and sucking the refrigerant so as to discharge the refrigerant from the outlet duct.
The power storage device according to claim 1 . the flow path member includes a plurality of cooling plates arranged along the second direction, each of which is formed with a part of the plurality of refrigerant flow paths;
The areas of the coolant channels are different for each of the cooling plates,
The power storage device according to claim 1 or 2 . The interval between the walls is defined by the width of the walls along the second direction,
The power storage device according to any one of claims 1 to 3 . A power storage device comprising a plurality of stacked power storage modules and a cooling mechanism for cooling the power storage modules,
The cooling mechanism is
A channel member formed with a plurality of coolant channels extending along a first direction intersecting the stacking direction of the power storage modules and arranged along a second direction intersecting the first direction and the stacking direction. and,
An introduction duct provided to extend along the second direction at one end portion of the flow channel member in the first direction and for introducing the coolant into each of the coolant flow channels. and,
a lead-out duct provided so as to extend along the second direction with respect to the other end portion of the flow path member in the first direction, and for circulating the coolant led out from each of the coolant flow paths. death,
The introduction duct is provided with an introduction port for introducing the refrigerant into the introduction duct ,
The lead-out duct is provided with an outlet for leading the refrigerant from the lead-out duct,
The inlet and the outlet are located on one end side of the flow path member in the second direction,
The flow path member is configured such that pressure loss when the refrigerant passes through the refrigerant flow path gradually decreases toward the other end of the flow path member in the second direction,
The coolant channel is formed in a tapered shape that narrows from one end of the channel member toward the other end in the first direction,
The flow path member is configured such that the pressure loss gradually decreases toward the other end portion of the flow path member in the second direction according to the contraction rate of the refrigerant flow path .
storage device. A power storage device comprising a power storage module and a cooling mechanism for cooling the power storage module,
The cooling mechanism is
a channel member formed with a plurality of coolant channels extending along a first direction and arranged along a second direction intersecting the first direction;
An introduction duct provided to extend along the second direction at one end portion of the flow channel member in the first direction and for introducing the coolant into each of the coolant flow channels. and,
a lead-out duct provided so as to extend along the second direction with respect to the other end portion of the flow path member in the first direction, and for circulating the coolant led out from each of the coolant flow paths. death,
The introduction duct is provided with an introduction port for introducing the refrigerant into the introduction duct,
The lead-out duct is provided with an outlet for leading the refrigerant from the lead-out duct,
The inlet and the outlet are located on one end side of the flow path member in the second direction,
The flow path member is configured such that pressure loss when the refrigerant passes through the refrigerant flow path gradually decreases toward the other end of the flow path member in the second direction,
In the flow path member, the pressure loss increases stepwise toward the other end of the flow path member in the second direction according to a change in the area of the cross section of the refrigerant flow path that intersects the first direction. is configured to be as small as
the flow path member includes a plurality of cooling plates arranged along the second direction, each of which is formed with a part of the plurality of refrigerant flow paths;
The areas of the coolant channels are different for each of the cooling plates,
storage device.

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