JP7215834B2 - Battery temperature controller - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heat transfer device for an assembled battery that transfers cold heat to cool the assembled battery, or transfers hot heat to heat the assembled battery.

For example, as a battery device for driving an electric motor of a hybrid vehicle, an electric vehicle, etc., a plurality of small single cells made of various types of secondary batteries such as lithium ion secondary batteries are connected in series or parallel to form an assembled battery. things are used. In particular, in electric vehicles, there is a demand for a large-capacity assembled battery due to the need to extend the cruising distance, so a plurality of assembled batteries are combined so as to be connected in series or in parallel. In addition, since the performance and life of the secondary battery change depending on the operating temperature, it is necessary to use the secondary battery at an appropriate temperature in order to use it efficiently for a long period of time.

As a method for efficiently cooling the assembled battery, a cooling member having a flat heat transfer surface and a coolant passage inside is used, and an elastically deformable thermal conductive sheet made of resin is placed between the cooling member and the assembled battery. A cooling device has been proposed in which an assembled battery and a cooling member are thermally connected by sandwiching them (see Patent Document 1).

In addition, as a heat transfer member interposed between a heat-generating member other than an assembled battery and a heat-dissipating member, a projecting body having elasticity is formed by cutting and raising a part of a metal plate. A heat transfer spring has been proposed that absorbs vibration generated between itself and a heat radiating member (see Patent Documents 2 and 3).

Japanese Patent No. 6020942 JP-A-10-303340 JP 2016-70408 A

Since the thermal conductivity of the thermally conductive sheet described in Patent Document 1 is lower than that of metal, the thermal resistance is large even if the adhesion between the assembled battery and the heat radiating member is maximized. In addition, it is inevitable that the mounting surface of the assembled battery with respect to the cooling member has a level difference due to the flatness tolerance of each unit cell and the assembly error of the plurality of unit cells. If the heat-conducting sheet is made sufficiently thick, the unevenness on the assembly surface of the assembled battery can be absorbed, and the heat-conducting sheet can be thermally connected to the cooling member. There is a problem that resistance also increases. Another problem is that the high thermal conductivity interface material (TIM) used as the thermally conductive sheet is expensive, and the thicker the TIM layer, the higher the cost.

According to the heat transfer springs described in Cited Documents 2 and 3, it is considered that the elastic force of the spring can absorb the step on the assembly surface of the assembled battery. Moreover, since it is made of metal, it has a smaller thermal conductivity than the resin-made heat-conducting sheet of Patent Document 1. However, some means such as a TIM is required to bring the heat transfer spring and the cooling member into close contact with each other, and heat transfer loss occurs between the heat transfer spring and the cooling member. Also, the cost increases due to the increase in the number of parts.

SUMMARY OF THE INVENTION In view of the background art described above, the present invention provides an assembled battery temperature control device capable of efficiently controlling each unit cell constituting an assembled battery to a predetermined temperature.

That is, the present invention has the configurations described in [1] to [8] below.

[1] Equipped with a temperature control plate having a flow path for a heat medium and mounting an assembled battery composed of a plurality of single cells,
A temperature control device for an assembled battery, wherein the temperature control plate has a spring portion at each position corresponding to each cell, the spring portion being deformed by contact with the cell.

[2] The assembled battery temperature control device according to the above item 1, wherein the spring portion is a plate spring formed by cutting a temperature control plate and bending a part of the temperature control plate.

[3] The assembled battery temperature control device according to [2] above, wherein the spring portion is a cantilever leaf spring.

[4] The assembled battery temperature control device according to any one of the preceding items 1 to 3, wherein the spring portion has a parallel portion parallel to a portion of the temperature control plate excluding the spring portion.

[5] The assembled battery temperature control device according to any one of the preceding items 1 to 4, wherein a heat medium is circulated in the flow path.

[6] The assembled battery temperature control device according to any one of the preceding items 1 to 4, wherein the temperature control plate is a heat pipe panel in which a working fluid is sealed in a flow path.

[7] The assembled battery temperature control device according to the above item 6, which includes a cold heat source and/or a heat source in contact with the temperature control plate.

[8] The temperature control plate includes a main body portion having a spring portion on which the assembled battery is mounted, and a bent portion extending from an end portion of the main body portion to provide a cold heat source and/or a hot heat source to the heat source contact portion. 8. The assembled battery temperature control device according to the preceding item 7, which has a heat source contact portion to be contacted.

According to the assembled battery temperature control device described in [1] above, when the assembled battery is mounted on the temperature control plate, the spring portion is recessed, and the spring portion comes into contact with the assembled battery due to the restoring force of the spring portion. Since the spring portions are provided at respective positions corresponding to the individual cells on the assembly surface of the temperature control plate, the temperature control plate can be reliably brought into contact with all the cells even if there is a step on the bottom surface of the assembled battery. It is possible to control the temperature of all the cells based on the temperature of the temperature control plate, and to reduce the variation in the temperature of the cells.

According to the assembled battery temperature control device described in [2] above, since the spring portion is a part of the temperature control plate, there is no heat transfer loss, and the temperature of the assembled battery can be efficiently controlled.

According to the assembled battery temperature control device described in [3] above, since the spring portion is a cantilevered leaf spring, the height of the spring portion can be changed according to the bent position, and the assembled battery is larger than the assembled battery. It can handle steps.

According to the assembled battery temperature control device described in [4] above, the contact area with the assembled battery is increased by the parallel portion of the spring portion, and the heat transfer efficiency can be enhanced.

According to the assembled battery temperature control device described in [5] above, the temperature control plate can be cooled or heated to a predetermined temperature by the heat medium flowing through the channel.

According to the assembled battery temperature control device described in [6] above, heat can be transferred by the heat pipe panel that constitutes the temperature control plate.

According to the assembled battery temperature control device described in [7] above, the temperature control plate is cooled or heated to a predetermined temperature by bringing a cold heat source and/or a hot heat source into contact with the temperature control plate. You can adjust the temperature.

According to the assembled battery temperature control device described in [8] above, the heat source contact portion that contacts the cold heat source and/or the heat source in the temperature control plate is formed by bending from the end portion of the body portion. , the increase in size of the temperature control device with the added heat source contact can be minimized.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows an example of the temperature control apparatus for assembled batteries of this invention, and an assembled battery. It is the perspective view which looked at the temperature control apparatus for assembled batteries of FIG. 1 from the back surface. FIG. 2B is a cross-sectional view taken along line 2B-2B of FIG. 2A; FIG. 2 is a cross-sectional view showing a state in which an assembled battery is mounted on the assembled battery temperature control device of FIG. 1 ; FIG. 3 is a perspective view showing another example of the assembled battery temperature control device of the present invention. FIG. 4 is a perspective view showing still another example of the assembled battery temperature control device of the present invention. FIG. 4 is a perspective view showing still another example of the assembled battery temperature control device of the present invention. It is the perspective view which looked at the temperature control apparatus for assembled batteries of FIG. 6 from the back surface. FIG. 7 is a perspective view showing a usage example of the assembled battery temperature control device of FIG. 6 ; FIG. 4 is a perspective view showing still another example of the assembled battery temperature control device of the present invention.

1 to 9 show a plurality of examples of the assembled battery temperature control device of the present invention.

In the following description, the up-down direction indicates the up-down direction shown in the drawings. Also, the same reference numerals denote the same or equivalent items, and overlapping descriptions are omitted.
[Shape of spring portion of temperature control plate]
(bridge-shaped spring part)
1 to 3 show an assembled battery 1 and a temperature control device 10 for this assembled battery.

The assembled battery 1 is composed of 12 rectangular parallelepiped unit cells 2, which are assembled by contacting large-area side surfaces of the unit cells 2 with each other. 1 and 3, the dimensional difference caused by the flatness tolerance of each unit cell 2 and the assembly error of the unit cells 2 is indicated as a step on the lower surface of the assembled battery 1. FIG. 1 and 3 omit illustration of the terminals and connection members of the cell 2, and show only the contour of the cell 2. FIG.

A temperature control device 10 includes a rectangular temperature control plate 11 on which the assembled battery 1 is mounted. As shown in FIGS. 2A and 2B, the temperature control plate 11 is made of an aluminum roll-bonded panel in which a channel 14 protrudes from the rear surface 13 of the assembly surface 12 of the assembled battery 1. An inlet member 15 and an outlet member 16 are mounted with openings on the short sides thereof. The temperature control plate 11 has 12 spring portions 18 formed at positions corresponding to the cells 2 in the central region. The spring portion 18 has 13 slit-like cuts 17 parallel to the short sides of the temperature control plate 11 made in the temperature control plate 11 at intervals corresponding to the thickness of the cell 2, and two adjacent cuts 17 are formed. It is a leaf spring formed by bending a belt-like portion between and in a direction projecting toward the mounting surface 12 side. The spring portion 18 is supported at both ends in the longitudinal direction (the short side direction of the temperature control plate 11), and the intermediate portion 18a is in the shape of a bridge parallel to the portion of the temperature control plate 11 excluding the spring portion 18. It has an elastic force to dent on the back surface 13 side of 11 and restore to the mounting surface 12 side.

As shown in FIGS. 2A and 2B, the temperature control plate 11 is a roll-bonded panel in which the flow path 14 is expanded on the back surface 13, and the assembly surface 12 is flat. The flow path 14 extends from one end along the long side of the temperature control plate 11, branches at each spring portion 18, joins from each spring portion 18, extends along the opposite long side, and extends along the other long side. reach the end. The heat medium introduced from the inlet member 15 passes through each spring portion 18 along the path of the flow path 14 and is discharged from the outlet member 16 . The temperature control plate 11 is cooled or heated to a temperature corresponding to the temperature of the heat medium introduced into the flow path 14 .

As shown in FIG. 3, when the assembled battery 1 is mounted on the assembly surface 12 of the temperature control plate 11, the spring portion 18 is recessed according to the vertical dimension of each unit cell 2, and the restoring force of the spring portion 18 The spring portion 18 firmly contacts the lower surfaces of all the single cells 2 . Since the spring portions 18 are provided at respective positions corresponding to the individual cells 2 on the assembly surface 12 of the temperature control plate 11 , the temperature control plate 11 can be securely mounted on all the cells even if there is a step on the lower surface of the assembled battery 1 . By contacting the unit cells 2 , the temperature of all the unit cells 2 can be controlled based on the temperature of the temperature control plate 11 . By bringing all of the cells 2 into contact with the spring portion 18, variations in the temperature of the cells 2 can be reduced. In addition, FIG. 3 omits illustration of the flow path 14 in the spring portion 18 .

Moreover, even when TIM is used to improve the adhesion between the assembly surface 12 of the assembled battery 1 and the temperature control plate 11, the amount of TIM used can be minimized. Therefore, by reducing the amount of TIM used, the thermal resistance of TIM can be minimized and the cost can be reduced.
(cantilevered spring)
The temperature control plate 21 of the temperature control device 20 in FIG. 4 and the temperature control plate 31 of the temperature control device 30 in FIG.

As shown in FIG. 4, the spring portion 28 of the temperature control plate 21 is formed by making a tortoiseshell bracket-shaped notch 27 corresponding to the number of two cells in the temperature control plate 21, and forming a trapezoidal portion surrounded by the notches 27 and connected on the long side. Then, the trapezoidal portion is supported by the long sides, bent upward toward the mounting surface 22, and further bent at the intermediate portion in the height direction of the trapezoidal portion. A tip portion 28 a of the spring portion 28 is parallel to the portion of the temperature control plate 21 excluding the spring portion 28 .

The temperature control plate 21 is a roll-bonded panel in which a channel 24 bulges out on the back surface 23 . The flow path 24 extends from one end along the long side of the temperature control plate 21, branches at each spring portion 28, joins from each spring portion 28, extends along the opposite long side, and ends at the other end. up to the department.

As shown in FIG. 5, the spring portion 38 of the temperature control plate 31 is a rectangular portion surrounded by the cuts 37 and connected on one long side by making square bracket-shaped cuts 37 corresponding to the number of the two cells in the temperature control plate 31 . is formed, the long side of the rectangular portion is supported and bent, and the intermediate portion in the short side direction is bent. A tip portion 38 a of the spring portion 38 is parallel to the portion of the temperature control plate 31 excluding the spring portion 38 .

The temperature control plate 31 is a roll-bonded panel in which flow paths 34 bulge out on both an assembly surface 32 and a back surface 33 . The flow path 34 extends from one end along the long side of the temperature control plate 31 and branches between the spring portions 38 . to the other end.

The cantilevered spring portions 28 and 38 are recessed toward the rear surfaces 23 and 33 of the temperature control plates 21 and 31 and have an elastic force to restore toward the mounting surfaces 22 and 32. Similarly, the spring portions 28 and 38 can be brought into firm contact with the lower surfaces of all the single cells 2 of the assembled battery 1 mounted on the temperature control plates 21 and 31 . In addition, the cantilevered spring portions 28 and 38 can easily change the protrusion height from the mounting surfaces 22 and 32 depending on the bending position. can be formed. As a result, it is possible to cope with a larger step of the assembled battery.

The spring portions 18, 28, 38 are part of the temperature control plates 11, 21, 31 whose temperature is controlled by the heat medium, and are integrated with the temperature control plates 11, 21, 31. is in direct contact with the assembled battery 1, the temperature of the assembled battery 1 can be efficiently adjusted without heat transfer loss. The height of the spring portions 18, 28, and 38 is sufficient to compensate for the difference in level occurring in the assembled battery 1, and the spring portions 18, 28, and 38 having such heights are cut into the temperature control plates 11, 21, and 31. It can be made by putting it in and bending it up.

Moreover, it is preferable that the spring portion has a parallel portion parallel to the portion of the temperature control plate excluding the spring portion. A spring portion having a parallel portion has a large contact area with the assembled battery and high heat transfer efficiency. The bridge-like spring portion 18 of FIG. 1 has a parallel portion at the intermediate portion 18a, and the cantilevered spring portions 28, 38 of FIGS. 4 and 5 have parallel portions at the tip portions 28a, 38a.
(Position of flow path)
The heat medium in the flow path is a heat transfer means, and in order to efficiently transfer heat, the flow path is preferably formed through each spring portion or along a route close to each spring portion. Even when passing through the spring portion, it is preferable that the flow path is formed especially through the portion that contacts the assembled battery. Although the channel must be formed by avoiding cuts, it can be formed in the spring portion as long as the channel is not crushed by bending. The flow path 14 in FIGS. 1 to 2B passes through the center of each spring portion 18 in the width direction and through an intermediate portion 18a (parallel portion) with which each unit cell 2 contacts. Channels 24 in FIG. 4 pass through the support side portion of each spring portion 28 . The flow path 34 in FIG. 5 does not pass through the spring portions 38 but passes through all adjacent spring portions 38 .

The temperature control plates 11, 21, and 31 of FIGS. 1 to 5 are configured such that the flow paths 14, 24, and 34 are opened at the ends of the temperature control plates 11, 21, and 31 to introduce the heat medium from the outside. ing. Also, the temperature control plate of the present invention can be composed of a heat pipe panel in which a working fluid is sealed in the flow path (see FIGS. 6 and 7).

Moreover, the type of the heat medium introduced into the flow path is not limited at all, and a long life coolant (LLC) can be exemplified.
(Cooling and heating of temperature control plate)
A temperature control device in which a temperature control plate is composed of a heat pipe panel cools and/or mounts a cold heat source and/or a hot heat source (hereinafter abbreviated as a "cold heat source") in contact with the temperature control plate. Can be heated. The contact position of the cold/heat source is not limited as long as it does not hinder the mounting of the assembled battery, but the cold/heat source contact portion can be added to the temperature control plate.

The temperature control plate 41 of the temperature control device 40 shown in FIGS. It has a heat source contact portion 43 which is bent in an L shape toward the mounting surface 12 and contacts a cold/heat source. The body portion 41 has a structure equivalent to that of the temperature control plate 11 of FIG. The heat source contact portion 43 is provided with a channel 44 that communicates with the channel 14 of the body portion 42, and these channels 14 and 44 are filled with working fluid. Further, the flow path 44 in the heat source contact portion 43 forms a mesh-like branched path, and is set so that the contact area between the cold/hot heat source (not shown) and the flow path 44 is large.

FIG. 8 shows a structure for cooling the assembled battery 1 using a low-temperature refrigerant from the refrigerating cycle 50 and the temperature control plate 41 . In the refrigerating cycle 50, the refrigerant condensed in the condenser 51 is fed through the expansion valve 52 into the refrigerant pipe 53, which is a flat multi-hole pipe. sent to The assembled battery 1 is mounted on the body portion 42 of the temperature control plate 41, and the refrigerant pipe 51 of the refrigerating cycle 50 is brought into contact with the heat source contact portion 43 as a cold heat source.

When the temperature control device 40 performs both cooling and heating, a hot heat source such as a heater is brought into contact with the temperature control plate 41 to switch between cold heat source and hot heat source. FIG. 7 shows an example in which a heat source 55 is brought into contact with the channel 14 on the rear surface 13 of the body portion 42 of the temperature control plate 41 .

When the heat source contact portion is added to the temperature control plate, the heat source contact portion can be provided on the same plane as the body portion without bending the extension portion from the body portion. However, by bending the heat source contact portion into an L shape with respect to the main body portion, the planar dimension of the temperature control device can be made smaller than when the heat source contact portion is not bent, thereby minimizing the size increase due to the addition of the heat source contact portion. be able to. be.

It is also possible to add two cold and hot heat source contact parts to the temperature control plate, one for cold heat source and one for hot heat source, respectively. Also, both cold and hot heat sources can be brought into contact with one cold and hot heat source contact portion. Further, the heat source contact portion can be provided on any side of the body portion.
(Temperature control plate for multiple assembled batteries)
The temperature control device of the present invention can mount a plurality of sets of assembled batteries on one temperature control plate. A temperature control device 60 in FIG. 9 includes a temperature control plate 61 on which two assembled batteries are mounted. The temperature control plate 61 is composed of a heat pipe panel having a body portion 62 and a bent heat source contact portion 63. The body portion 62 is formed with two rows of spring portions 68a and 68b. 68b is composed of a plurality of spring portions 18; Further, the flow path 64 branches to each spring portion 18 and extends to the heat source contact portion 63, and assembled batteries are mounted on the respective spring portion rows 68a and 68b.

In the present invention, the material of the temperature control plate is preferably a metal having a high thermal conductivity such as aluminum or copper, or an alloy of these metals. Moreover, it is preferable to form the spring portion and the flow path using a roll bond panel. Although the present invention does not exclude a temperature control plate in which flow path pipes are bonded to a flat plate, a roll-bonded panel is thin and lightweight, and is suitable for a temperature control device for an on-vehicle battery.

Further, in the assembled battery temperature control device of the present invention, the channel of the temperature control plate can be brought into contact with the battery case or the insulating plate to exhaust heat to them.

INDUSTRIAL APPLICABILITY The present invention is used for adjusting the temperature of an assembled battery in an electric vehicle equipped with an assembled battery composed of a plurality of lithium ion secondary battery cells.

DESCRIPTION OF SYMBOLS 1... Assembled battery 2... Single cell 10, 20, 30, 40, 60... Temperature control device 11, 21, 31, 41, 61... Temperature control plate 12, 22, 32... Assembly surface 14, 24, 34, 44, 64... Flow path 17... Slit (notch)
18, 28, 38 Spring portion 18a Intermediate portion (parallel portion)
27... Tortoiseshell bracket-shaped notch 28a... Tip portion (parallel portion)
37... Bracket-shaped notch 38a... Tip part (parallel part)
42, 62... Main body parts 43, 63... Heat source contact part 53... Refrigerant pipe (cold heat source)
55 heat source

Claims (7)

Equipped with a temperature control plate having a flow path for a heat medium and mounting an assembled battery composed of a plurality of single cells,
the temperature control plate has a spring portion at each position corresponding to each unit cell and deformed by contact with the unit cell, and the flow path branches and passes through each spring portion,
A temperature control device for an assembled battery, wherein the spring portion is a plate spring formed by cutting a temperature control plate and bending a portion of the temperature control plate including the flow path . 2. The assembled battery temperature control device according to claim 1, wherein the spring portion is a cantilever leaf spring. The assembled battery temperature control device according to claim 1 or 2, wherein the spring portion has a parallel portion parallel to a portion of the temperature control plate excluding the spring portion. The assembled battery temperature control device according to any one of claims 1 to 3, wherein a heat medium is circulated through the channel. The assembled battery temperature control device according to any one of claims 1 to 3, wherein the temperature control plate is a heat pipe panel in which a working fluid is sealed in a channel. 6. The assembled battery temperature control device according to claim 5, comprising a cold heat source and/or a heat source that contacts the temperature control plate. The temperature control plate has a body portion having a spring portion on which the assembled battery is mounted, and a heat source contact portion extending from an end portion of the body portion and bent to contact a cold heat source and/or a heat source. The assembled battery temperature control device according to claim 6 .

Images