WO2016063434A1

WO2016063434A1 - Power supply device

Info

Publication number: WO2016063434A1
Application number: PCT/JP2015/003362
Authority: WO
Inventors: 達人堀内; 新吾越智; 橋本　裕之
Original assignee: 三洋電機株式会社
Priority date: 2014-10-21
Filing date: 2015-07-03
Publication date: 2016-04-28

Abstract

In order to provide a structure capable of stably cooling battery cells, this power supply device includes a plurality of unit modules (20), and a holder (30). The plurality of unit modules (20) are arranged along one direction, and each unit module (20) includes a plurality of battery cells, and an annular ring (24) that holds the plurality of battery cells. The holder (30) holds the plurality of unit modules (20), and is provided with an inlet port and an outlet port to allow a coolant to flow therethrough. The annular ring (24) is located around the outer circumference of each unit module (20) that includes the annular ring (24), and forms a gap between the adjacent unit modules (20) by the thickness of the annular ring (24). The gap is in communication with the inlet port and the outlet port provided to the holder (30).

Description

Power supply

The present invention relates to a power supply device.

In recent years, electric vehicles equipped with a power supply device composed of a plurality of battery cells have become widespread as power sources for driving hybrid cars and electric vehicles. In addition, a power supply device that is used in a power storage system combined with a power generation device such as a solar cell and stores power generated by the power generation device is also known. In these power supply apparatuses, as the battery cell, a chargeable / dischargeable secondary battery such as a lithium ion battery or a nickel metal hydride battery is used.

As this type of power supply device, a power supply device including a plurality of battery modules is known (Patent Document 1). In the power supply device of Patent Document 1, each battery module includes a metal case and a plurality of battery cells housed in the metal case. The metal case is provided with external terminals connected to the output terminals of a plurality of battery cells to be stored. Several battery modules are laminated | stacked and arrange | positioned in the same direction, and adjacent battery modules are connected via each external terminal. Moreover, it is known that a battery cell will generate | occur | produce according to charging / discharging, and battery performance will deteriorate by being charged / discharged under high temperature. In the power supply device of Patent Document 1, a spacer that forms a gap between adjacent metal cases is provided between the battery modules, and flows into the gap formed between the battery modules. The battery module is cooled by the cooling air. In this structure, the battery cell accommodated in the metal case is cooled via the metal case.

There is also known a power supply device including a plurality of unit modules formed by surrounding a pair of battery cells with a metal holding member and a resin case for holding the plurality of unit modules (Patent Document 2). . The resin case includes an upper frame member and a lower frame member. The resin case surrounds the edge of the unit module and has a shape that exposes the metal holding member of the unit module to the outside. Specifically, the lower frame member is provided with a plurality of partition walls so that a plurality of unit modules can be inserted, and a gap is formed between adjacent unit modules. ing. The upper frame member and the lower frame member are provided with inlets and outlets at positions corresponding to the gaps between the unit modules so that the gaps between the unit modules serve as cooling channels. . With this configuration, the power supply device of Patent Document 2 forms a flow path through which cooling air passes through the resin case, and can cool the battery cell by cooling the metal holding member of the unit module. It is like that.

JP 2013-2011136 A Special table 2009-529216

Any of the above-described power supply devices is configured to indirectly cool the battery cell by cooling a metal member that is in thermal contact with the battery cell. However, in this configuration, if the adhesion between the battery cell and the metal member is insufficient, an air layer is formed between the battery cell and the metal member, which may reduce the cooling efficiency. Since tolerances occur in the dimensions of the members, there is a problem that the production efficiency is remarkably lowered when it is attempted to ensure the adhesion between the battery cells and the metal members.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power supply device having a configuration capable of stably cooling battery cells while having a simple configuration.

The power supply device of the present invention is a plurality of unit modules arranged along one direction, and each of the unit modules includes a plurality of battery cells and at least one annular ring body. A holding body that holds the plurality of unit modules and is provided with an inlet and an outlet for flowing the refrigerant. The at least one annular ring body is located on the outer periphery of a unit module including the annular ring body, and a gap is formed between adjacent unit modules depending on the thickness of the annular ring body. The gap is connected to the inlet and the outlet provided in the holding body.

According to the configuration of the power supply device described above, the plurality of battery cells are held by the annular ring body, and a gap can be formed between adjacent unit modules depending on the thickness of the annular ring body. In this configuration, at least a part of one surface of the battery cell can be exposed to a gap formed between adjacent unit modules, and the battery cell is directly connected with the refrigerant flowing through the gap formed between adjacent unit modules. Can be cooled. Therefore, the battery cell can be stably cooled with a simple configuration.

It is a perspective view of the power supply device in the embodiment of the present invention. It is a perspective view of the unit module shown in FIG. It is a front view of the unit module shown in FIG. It is a front view which shows one Example of the battery cell in embodiment of this invention. It is a front view which shows the other Example of the battery cell in embodiment of this invention. It is sectional drawing of the unit module shown in FIG. It is sectional drawing which shows the modification of the unit module in embodiment of this invention. It is a disassembled perspective view of the power supply device of FIG. It is a top view of the lower case body shown in FIG. FIG. 3 is a side view of the annular ring body shown in FIG. 2. It is a side view which shows the 1st modification of the cyclic | annular ring body in embodiment of this invention. It is a side view which shows the 2nd modification of the annular ring body in embodiment of this invention.

FIG. 1 shows a power supply device 1 according to an aspect of the present invention. The power supply device 1 shown in FIG. 1 includes a plurality of unit modules 20 serving as a power source and a holding body 30 in which the plurality of unit modules 20 are accommodated. The holding body 30 is provided with an external terminal 32, and the external terminal 32 is electrically connected to the unit module 20 held by the holding body 30. With this configuration, the power of the power supply device 1 can be output or a plurality of power supply devices 1 can be connected via the external terminal 32. The holding body 30 includes a lower frame body 33 and an upper frame body 31, and a plurality of unit modules 20 are held between the lower frame body 33 and the upper frame body 31.

2 and 3, the unit module 20 includes a plurality of battery cells 21 and a plurality of annular ring bodies 24 that hold the plurality of battery cells 21. The plurality of annular ring bodies 24 are band-shaped members having a predetermined thickness and a predetermined width, and are located on the outer periphery of the unit module 20. The unit module 20 can also be configured with a plurality of battery cells 21 and a single annular ring body 24 surrounding the plurality of battery cells 21.

The battery cell 21 which comprises the unit module 20 is a secondary battery which can be charged / discharged. Specifically, a secondary battery such as a lithium ion battery or a nickel metal hydride battery can be used. 4 and 5 are diagrams for explaining a specific configuration of the battery cell 21 described above, and a pouch battery is illustrated as a representative configuration. The battery cell 21 in FIGS. 4 and 5 includes an exterior body 22 formed of a deformable laminate film, a power generation element enclosed in the exterior body 22, and an electrode tab 23 connected to the power generation element. The The power generation element includes an electrode body and an electrolytic solution. The electrode tab 23 is an output terminal of the battery cell 21 and is led out from the inside of the exterior body 22 from the outside of the exterior body 22.

This type of battery cell 21 is known to have a flat wound electrode body or a laminated electrode body as an electrode body. The wound electrode body is an electrode body formed in a flat shape by winding a positive electrode plate and a negative electrode plate through a separator, and then pressing them. The laminated electrode body is an electrode body formed by laminating a sheet-like positive electrode plate and a negative electrode plate via a separator. In addition, the structure of an electrode body should just be able to enclose a power generation element in the exterior body 22, and does not necessarily need to be restricted to the above-mentioned structure.

The laminate film is a sheet-like metal / resin composite film having a five-layer structure of resin layer (polypropylene) / adhesive layer / aluminum alloy layer / adhesive layer / resin layer (polypropylene). The exterior body 22 is formed of this laminate film, and has an electrode body storage space therein. Specifically, in the battery cell 21 illustrated in FIGS. 4 and 5, the electrode body is disposed on the exterior body 22 composed of a single laminate film, the exterior body 22 is folded, and the sides other than the folded sides are arranged. On the side, the overlapping outer package 22 is formed by heat welding. 4 has a pair of electrode tabs 23 extending from one side of the outer package 22 when the laminate film is thermally welded. Further, in the battery cell of FIG. 5, one electrode tab 23 of a pair of electrode tabs is extended from two sides located at both ends of the exterior body 22 when the laminate film is heat-welded.

The battery cell 21 having the above configuration is formed in a thick rectangular plate shape and includes a deformable exterior body 22. Moreover, since the exterior body 22 is comprised with a laminate film, the exterior body 22 can be insulated with respect to the electric power generation element enclosed inside, forming the exterior body 22 with a metal. The battery cell 21 having this configuration is characterized in that the laminate film is deformed relatively easily by an external force, so that the shape stability is low, and since the number of components constituting the battery cell 21 is small, the outer shape of the battery cell 21 can be reduced. There is.

In the above description, the configuration including the pouch battery has been described based on FIGS. 4 and 5. However, the power supply device 1 of the present invention does not necessarily need to be a pouch battery, and a power generation element is provided in a box-shaped battery case. It is also possible to use a prismatic battery having a configuration in which is enclosed. A prismatic battery has a structure in which an electrode body such as a wound electrode body or a laminated electrode body and an electrolytic solution are stored in a metal battery case with a bottomed rectangular parallelepiped and the upper surface is opened, and the upper surface is sealed with a sealing plate. It has been known. Such a battery cell 21 also has a thick rectangular plate shape. In the battery cell 21 having this configuration, the exterior body 22 has a potential because the exterior body 22 is formed of a metal battery case, and the exterior body 22 is formed of a strong battery case. Deformation can be suppressed, and there are features such as high shape stability.

2 and 3, the annular ring body 24 is a holding member formed in a band shape so as to be able to surround the plurality of battery cells 21. The plurality of battery cells 21 are inserted into the annular ring body 24 in a state of being stacked with their main surfaces facing each other, and the unit module 20 is configured. The annular ring body 24 is preferably formed of a resin, and can also be formed of an elastic member so that the inserted plurality of battery cells 21 can be fixed and held. As the resin member having elasticity, an elastomer such as rubber can be used. As described above, the annular ring body 24 is formed with a predetermined width. However, by changing the width of the annular ring body 24, the binding strength of the unit modules 20 can be changed.

2 is composed of two battery cells 21 and three annular ring bodies 24 surrounding the two battery cells 21, respectively. In this configuration, the plurality of stacked battery cells 21 are held by the plurality of annular ring bodies 24, and both ends of the plurality of battery cells 21 are held by the annular ring bodies 24. Therefore, the plurality of battery cells 21 can be firmly assembled, and handling properties during assembly can be improved. This configuration has a particularly excellent effect when a pouch battery is employed as the battery cell 21.

Specifically, the pouch battery has a configuration in which the electrode tabs of adjacent pouch batteries are close to each other because the thickness in the width direction of the battery cell 21 is thinner than the battery cell 21 having another shape. Therefore, in combination with the relatively easy deformation of the outer package of the pouch battery, there is a risk of unintentional contact with the electrode tab 23 of the adjacent pouch battery. For example, this problem becomes significant when the unit module 20 is moved in the assembly process of the power supply device 1 and the like. However, in the above-described configuration, the plurality of battery cells 21 constituting the unit module 20 include a plurality of annular ring bodies. 24, the unit module 20 can be moved in a stable state.

6 is a cross-sectional view of the unit module 20 of FIG. 2, and FIG. 7 is a cross-sectional view of the unit module 20 of a modification. When the battery cell 21 is in an abnormal state, gas may be generated from the electrolyte or the like, and the internal pressure of the exterior body 22 may increase. Therefore, the exterior body 22 of the pouch battery needs to be heat-welded in an area of a predetermined range or more so that a certain degree of hermeticity can be secured against an increase in internal pressure. On the other hand, as described above, in the pouch battery, the outer periphery of the exterior body 22 is sealed by thermal welding, but no power generation element is arranged between the exterior bodies 22 to be thermally welded. Therefore, a dead space is generated in the peripheral portion of the pouch battery, which becomes a factor in reducing the energy density with respect to the space occupied by the battery cell 21.

In the unit module 20 of FIG. 7, a plurality of pouch batteries are stacked in a state where the peripheral edge portion of the heat-welded exterior body 22 is folded. In the configuration of the pouch battery, compared to the thickness of the electrode body storage space in which the power generation element is stored, the thickness of the peripheral portion to be heat-welded is thin, so by folding the peripheral portion of the heat-welded exterior body 22, The space occupied by the battery cell 21 can be reduced.

Compared with the unit module 20 illustrated in FIG. 6 in which the peripheral portion is not folded, the unit module 20 having the above configuration has the pouch battery firmly held by the annular ring body 24, so that the battery can be more stably maintained. Cells can be assembled.

Furthermore, it is also possible to adopt a configuration in which the peripheral portion of the folded exterior body of the adjacent pouch battery is brought into contact. In this configuration, adjacent battery cells 21 can be held using a force that the peripheral portion of the folded exterior body 22 tries to restore the original shape.

As shown in FIGS. 1, 8 and 9, the holding body 30 includes a lower frame body 33 and an upper frame body 31, and a plurality of unit modules are provided between the lower frame body 33 and the upper frame body 31. 20 is arranged. As described above, the annular ring body 24 having a predetermined thickness is located on the outer periphery of the unit module 20, and a plurality of unit modules 20 are arranged adjacent to each other. A gap corresponding to at least the thickness of the annular ring body 24 is formed.

As shown in FIG. 1, a through hole 35 is formed on the top surface of the upper frame body 31. As shown in FIG. 9, a through hole 35 is formed in the bottom surface of the lower frame body 33. The through holes 35 formed in the upper frame body 31 and the lower frame body 33 are an inlet and an outlet for introducing a refrigerant into the holding body 30. The holding body 30 is provided so as to correspond to the gap formed between the unit modules 20 in which each through hole is adjacent. That is, a gap formed between adjacent unit modules is communicated with an inflow port and an outflow port provided in the holding body 30.

In the above configuration, one surface of the battery cell 21 is exposed in the gap formed between the adjacent unit modules 20. Therefore, the battery cell 21 which comprises the unit module 20 can be comprised so that it may be directly exposed to a refrigerant | coolant, and the battery cell 21 can be cooled stably. In addition, since the annular ring body 24 is configured to extend along the flow path direction of the refrigerant flowing through the gap formed between the adjacent unit modules 20, the annular ring body 24 inhibits the flow of the refrigerant. This can be suppressed. Moreover, it is preferable to set it as the structure provided so that the mutual annular ring body 24 may oppose in the adjacent unit module 20. FIG. In this configuration, the flow path cross-sectional area of the gap formed between adjacent unit modules 20 can be increased, and pressure loss that occurs when the refrigerant flows can be reduced. In addition, the end portions of the annular ring body 24 and the partition wall 34 can be chamfered. The annular ring body 24 and the partition wall 34 whose end portions are chamfered can suppress generation of turbulent flow, and can reduce pressure loss generated when the refrigerant flows.

As described above, the annular ring body 24 can change the binding strength of the unit modules 20 by changing the width of the annular ring body 24, but the width of the annular ring body 24 is large. Then, the area of the battery cell that is directly exposed to the refrigerant is reduced. Accordingly, the width and thickness of the annular ring body 24 are preferably designed in consideration of the binding strength of the unit modules 20 and the cooling efficiency.

Further, as shown in FIGS. 8 and 9, the lower frame body 33 may be configured such that a plurality of partition walls 34 are provided on the inner wall at the bottom of the lower frame body 33. FIG. 9 illustrates the lower frame body 33 provided with six partition walls. In the lower frame body 33 of FIG. 9, the six partition walls 34 define four spaces V1 for housing the unit modules 20 and three spaces V2 communicating with the through holes 35 provided in the lower frame body 33. is doing. According to this configuration, the unit module 20 is inserted into the space V <b> 1 formed by the partition wall 34. Further, the unit module 20 is guided to the corresponding space V1 by the partition wall 34 when inserted into the space V1.

In addition, although the dimension of the space V1 is prescribed | regulated by the position in which the partition wall 34 is provided, it is preferable to form a little larger than the width | variety of the unit module 20 so that the unit module 20 can be inserted easily. Further, in the configuration in which the unit module 20 is formed at an interval substantially equal to the width of the unit module 20, the annular ring body 24 of the unit module is fitted in the space V <b> 1 formed by the partition wall 34. In this configuration, since the annular ring body 24 is fixed to the lower frame body 33, the unit module 20 can be stably held by the lower frame body 33 during assembly, and workability in the manufacturing process is improved. Can do. Also, the surface of the annular ring body 24 can be subjected to coating or surface treatment that reduces the friction coefficient. In this configuration, the annular ring body 24 can be easily inserted, and the workability in the manufacturing process can be further improved.

10 to 12 are views for explaining another embodiment of the annular ring body 24. FIG. 10 is a side view of the annular ring body 24 illustrated in the unit module of FIG. The annular ring body 24 of FIGS. 11 and 12 is an annular ring body 24 for constituting the unit module 20 with a large number of battery cells, and mainly when the unit module 20 is constituted by three or more battery cells. It is suitable for. The annular ring body 24 shown in FIG. 11 is provided with a plurality of convex portions 25 projecting inward on the inner wall of the annular ring body 24. Each battery cell 21 is held in a state of being spaced apart by a plurality of convex portions 25. With this configuration, in addition to the gap formed between adjacent unit modules 20, a gap can also be formed between the plurality of battery cells 21 constituting the unit module 20. The gaps provided between the battery cells 21 are connected to the plurality of through holes 35 provided in the holding body 30 in the same manner as the gaps formed between the adjacent unit modules 20. With this configuration, not only the battery cells 21 located outside the unit module 20 but also the battery cells 21 arranged inside the unit module 20 can be directly cooled via the refrigerant.

The annular ring body 24 shown in FIG. 12 is provided with a concave portion 26 on the outer wall of the annular ring body 24 in addition to the configuration of the convex portion 25. The concave portion 26 is provided corresponding to the convex portion 25, and is configured such that the pair of partition walls 34 of the lower frame body 33 are fitted. Specifically, among the plurality of partition walls 34, a pair of partition walls 34 that divide a space V <b> 2 that communicates with the outflow port therebetween are fitted into the recess 26 of the annular ring body 24. As described above, since the concave portion 26 is provided corresponding to the convex portion 25 for forming a gap between the battery cells 21, the partition wall 34 that forms the outflow port or the space V2 that communicates with the outflow port. Is inserted into the recess 26 so that the gap between the battery cells 21 and the through hole 35 can be aligned.

The present invention has been described based on the embodiments. Those skilled in the art will understand that these embodiments are exemplifications, and that various modifications can be made to the combinations of the respective constituent elements and the respective treatment processes, and such modifications are also within the scope of the present invention. It is where it is done.

1 power supply unit, 20 unit module, 21 battery cell, 22 exterior body, 23 electrode tab, 24 annular ring body, 25 convex part, 26 concave part, 30 holding body, 31 upper frame body, 32 external terminal, 33 lower frame body, 34 partition walls, 35 through holes

Claims

A plurality of unit modules arranged along one direction, each unit module including a plurality of battery cells and at least one annular ring body;
A holding body that holds the plurality of unit modules and is provided with an inlet and an outlet for flowing a refrigerant;
The at least one annular ring body is located on the outer periphery of the unit module including the annular ring body, and forms a gap between adjacent unit modules depending on the thickness of the annular ring body, and the gap is the holding body. A power supply device that is in communication with the inflow port and the outflow port that are provided in the airflow path.
The power supply device according to claim 1,
Each of the plurality of battery cells includes an exterior body formed in a thick rectangular plate shape, and adjacent battery cells are stacked in a state where the exterior bodies face each other.
The power supply device according to claim 1 or 2, wherein
The plurality of unit modules are power supplies in which annular rings are arranged to face each other.
The power supply device according to any one of claims 1 to 3,
The at least one annular ring body is a plurality of annular ring bodies, and the plurality of annular ring bodies extend along a flow path direction of the refrigerant flowing through the gap.
The power supply device according to any one of claims 1 to 4,
The at least one annular ring body includes at least one protrusion provided on an inner wall of the annular ring body so as to be positioned between adjacent battery cells among the plurality of battery cells held by the annular ring body. Including power supply.
The power supply device according to any one of claims 1 to 5,
The holding body includes a first frame member provided with a plurality of partition walls, a second frame member connected to the first frame member, and the plurality of unit modules positioned between the first frame member and the second frame member. A frame member,
The plurality of partition walls are power supply devices that guide the plurality of unit modules to a predetermined position.
The power supply device according to claim 6,
The power supply apparatus, wherein the at least one annular ring body is fitted into the plurality of partition walls.
The power supply device according to claim 7,
The at least one annular ring body is a power supply device in which a recess is provided in an outer wall of the annular ring body, and one of the plurality of partition walls is inserted into the recess.
The power supply device according to any one of claims 1 to 8,
The plurality of battery cells are a plurality of pouch batteries including a deformable exterior body, a power generation element enclosed in the exterior body, and an electrode tab connected to the power generation element and led out from the exterior body. ,
The plurality of pouch batteries are power supply devices that are inserted into the annular ring body in a state in which at least a part of the periphery of the exterior body is bent.
The power supply device according to claim 9,
The power supply apparatus according to claim 1, wherein the plurality of pouch batteries are in contact with each other of the folded exterior bodies of adjacent pouch batteries.