WO2016132405A1

WO2016132405A1 - Power source device

Info

Publication number: WO2016132405A1
Application number: PCT/JP2015/003407
Authority: WO
Inventors: 橋本　裕之; 新吾越智; 達人堀内
Original assignee: 三洋電機株式会社
Priority date: 2015-02-16
Filing date: 2015-07-07
Publication date: 2016-08-25

Abstract

In order to improve strength against vibration and impacts, this power source device is provided with multiple battery modules 1, a pair of endplates 40, and restraining members 50 linked to the end plates 40. On a mounting surface orthogonal to a second direction Z, the battery modules 1 are arranged along a first direction Y. The battery modules house multiple battery cells 10, and include a module case 30 comprising at least a base unit 31 and a cover unit 34. The base unit 31 comprises an opening 32 which opens towards the second direction Z and a fixed unit 33 which is fixed to the mounting surface. The cover unit 34 is linked to the opening 32 such that the battery cell 10 is positioned between the cover unit 34 and the base unit 31. The endplates 40 are arranged at both ends of the battery modules 1 in the first direction Y. The restraining members 50 extend in the first direction Y and include a displacement regulating part 51 which abuts against the surfaces of the cover units 34 positioned in the second direction Z and the surfaces of the cover units 34 positioned in a third direction X.

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 disclosed in the following patent document, a power supply device including a plurality of battery modules is known (Patent Document 1). In the power supply device of Patent Document 1, the battery module includes a plurality of battery cells having a wide surface, and a case including a base portion and a cover portion. The base has a fixing portion for fixing to the mounting surface, and has an open structure in which at least one surface is open. A plurality of battery cells are inserted from one open surface, and the base is arranged in a posture in which the wide surfaces are parallel to each other. A cover part is connected with the base part in the state which inserted the some battery cell.

With the above configuration, a plurality of battery cells can be stored in the case. The battery cell expands due to charging / discharging and deterioration. However, in the power supply device having this configuration, the battery cell is accommodated inside the case, so that the battery cell dimensional change can be absorbed and the battery module dimensional change can be absorbed. Can be suppressed.

Special table 2014-519153

The above-described power supply device is configured to include a case including a base portion and a cover portion. The cover of the case is not directly fixed to the mounting surface, so when a relatively strong impact is applied to the power supply device, the case is damaged or the cover connected to the base is removed. There was a risk of it.

The present invention has been made in view of such a situation, and a main object thereof is a battery module having a configuration in which a plurality of battery cells are housed in a case formed of a pair of case bodies, and has high strength against vibration. It is providing a power supply device provided with the battery module of a structure.

A power supply device according to an aspect of the present invention includes a plurality of battery modules, a pair of end plates, and a restraining member coupled to the pair of end plates. The plurality of battery modules are arranged along the first direction among the first direction, the second direction, and the third direction that are three directions orthogonal to each other, and are arranged in the second direction. It is arrange | positioned with respect to the mounting surface perpendicular | vertical. Each battery module includes a plurality of battery cells and a resin module case that houses the plurality of battery cells and includes at least a base portion and a cover portion. The base includes an opening having an open surface that opens in the second direction, and a fixing portion that is fixed to the mounting surface on which the battery module is disposed. The cover part is connected to the opening in the second direction so that a plurality of battery cells are positioned between the cover part and the base part. The pair of end plates are disposed at both ends of the plurality of battery modules in the first direction. The restraining member extends along the first direction, and abuts against the surfaces of the plurality of cover portions located in the second direction and the surfaces of the plurality of cover portions located in the third direction. A displacement restricting portion is included.

According to the configuration of the power supply device according to an aspect of the present invention, since the displacement of the cover portion can be suppressed by the displacement restricting portion of the restraining member, the strength against vibration and impact of the module case can be improved. Specifically, when the relative position of the cover part with respect to the base part is displaced, stress is applied to the connecting part of the cover part and the base part, but the displacement of the cover part is suppressed by the displacement restricting part of the restraining member. It is possible to prevent the relative position with respect to the base from being displaced. As a result, stress can be reduced at the connecting portion between the cover portion and the base portion, and the strength against vibration and impact of the module case can be improved.

It is a perspective view of the power supply device in 1st embodiment of this invention. It is a perspective view of the battery module of FIG. It is a disassembled perspective view of the battery module of FIG. It is a front view of a pouch battery showing an example of a battery cell in an embodiment of the present invention. It is a front view of the pouch battery which shows another example of the battery cell in embodiment of this invention. It is a disassembled perspective view of the unit module of FIG. It is sectional drawing of the unit module of FIG. In 1st embodiment of this invention, it is sectional drawing of the power supply device provided with the exterior case. It is sectional drawing which shows the cross section from another direction of the power supply device of FIG. It is a perspective view of the power supply device which shows the restraint member of the modification in embodiment of this invention. In 2nd embodiment of this invention, it is sectional drawing of the power supply device provided with the exterior case. It is a perspective view of the battery module of FIG. It is a disassembled perspective view of the unit module with which the battery module of FIG. 12 is provided.

FIG. 1 shows a power supply device according to the first embodiment of the present invention. FIG. 1 is a perspective view, and for convenience of explanation, a first direction Y, a second direction Z, and a third direction X that are orthogonal to each other are shown in FIG. In FIG. 1, the first direction Y corresponds to the depth direction, the second direction Z corresponds to the height direction, and the third direction X corresponds to the width direction. In the following description, when referring to the above-described three directions, it is assumed that each direction illustrated in FIG. 1 is referred to.

1 includes a plurality of battery modules 1, a pair of end plates 40, and a restraining member 50 coupled to the pair of end plates 40. The battery module 1 has a substantially rectangular parallelepiped shape, and has a pair of opposing surfaces on both sides in the first direction Y. The plurality of battery modules 1 are arranged along the first direction Y in a posture in which the opposing surfaces face each other. The pair of end plates 40 are arranged at positions facing the facing surfaces of the battery module 1 located at both ends in the stacking direction of the battery modules 1. The pair of end plates 40 positioned at both ends of the plurality of battery modules 1 collects the plurality of battery modules 1 via the restraining members 50 connected to the pair of end plates 40.

2 and 3, the battery module 1 includes a unit module 2 including a plurality of battery cells 10 and a resin module case 30 in which the unit module 2 is accommodated. The module case 30 is configured to be dividable in the second direction Z so that the unit module 2 can be accommodated therein. Specifically, the module case 30 includes a base 31 having an opening 32 having at least one surface opened, and a cover 34 coupled to the opening 32, and the cover 34 is moved from the base 31 in the second direction. It can be separated into Z. According to this configuration, the unit module 2 including the plurality of battery cells 10 can be inserted into the base portion 31 from the second direction Z. The unit module 2 is disposed between the base portion 31 and the cover portion 34 by connecting the cover portion 34 to the opening portion 32 with the plurality of unit modules 2 inserted into the base portion 31.

The battery cell 10 is a chargeable / dischargeable secondary battery. 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 10 described above, and illustrate a pouch battery as a typical configuration. The battery cell 10 of FIGS. 4 and 5 includes an exterior body 11 formed of a deformable laminate film, a power generation element enclosed in the exterior body 11, and an electrode tab 12 connected to the power generation element. The The power generation element includes an electrode body and an electrolytic solution. The electrode tab 12 is an output terminal of the battery cell 10 and is led out from the exterior of the exterior body 11 from the interior of the exterior body 11.

This type of battery cell 10 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 an electric power generation element in the exterior body 11, and does not necessarily need to be restricted to the above-mentioned structure.

The laminate film is a sheet-like composite film having a five-layer structure of resin layer (polypropylene) / adhesive layer / aluminum alloy layer / adhesive layer / resin layer (polypropylene). The exterior body 11 is formed of this laminate film, and has an electrode body housing space therein. Specifically, the battery cell 10 illustrated in FIGS. 4 and 5 includes an electrode body disposed on a single laminate film, folded the laminate film, and laminated laminate films on the sides other than the folded sides. It is formed by heat welding. 4 has a pair of electrode tabs 12 extending from one side of the outer package 11 when the laminate film is thermally welded. Further, in the battery cell of FIG. 5, one electrode tab 12 of the pair of electrode tabs 12 is extended from two sides located at both ends of the exterior body 11 when the laminate film is heat-welded. .

The battery cell 10 having the above configuration has a simple structure, and the outer shape of the battery cell can be made relatively small. Moreover, since the exterior body 11 is comprised with a laminate film, the exterior body 11 can be insulated with respect to the electric power generation element enclosed inside, forming the exterior body 11 with a metal. The heat dissipation of the battery cell 10 can be improved by forming the exterior body 11 with a metal. On the other hand, since the laminate film is relatively easily deformed by an external force, the stability of the shape of the exterior body 11 is low.

As shown in FIG. 6, the unit module 2 includes a plurality of battery cells 10 stacked in a posture in which the wide surfaces face each other, and a holding body 20 that holds the stacked battery cells 10. The holding body 20 shown in FIG. 6 is composed of a pair of U-shaped metal plates in cross section, and each metal plate has a main surface portion 20a facing the wide surface of the battery cell 10 and a flange portion 20b protruding from the main surface. And. The pair of metal plates can sandwich the battery cell 10 in a space formed between the pair of metal plates by engaging or fitting the flange portions 20b. According to this structure, since the battery cell 10 is hold | maintained by the holding body 20 with high rigidity, a deformation | transformation of the battery cell 10 provided with the exterior body 11 with low rigidity can be suppressed.

6 is further provided with a heat transfer plate 21 between the plurality of battery cells 10 held by the holding body 20. According to this configuration, since the heat transfer plate 21 is disposed between adjacent battery cells 10, the battery cell 10 can be cooled by heat transfer to the heat transfer plate 21 in addition to heat transfer to the holding body 20. it can. When the number of battery cells 10 constituting the unit module 2 is large, the cooling efficiency of the battery cells 10 arranged in the central portion of the unit module 2 may be significantly reduced. This is particularly effective in such a configuration. is there.

Further, as shown in FIGS. 6 and 7, a fitting portion 22 that fits with the flange portion 20 b of the holding body 20 can be formed in the lower portion of the heat transfer plate 21. By forming the fitting portion 22 in the heat transfer plate 21, the heat transfer plate 21 is held by the adjacent battery cells 10 and is also fixed to the holding body 20. Deviation can be prevented.

In the above description, the battery module 1 including a pouch battery has been described as the battery cell 10. However, the battery cell 10 is not necessarily a pouch battery, and a configuration in which a power generation element is enclosed in a box-shaped battery case. Or a square battery. 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 also has a thick rectangular plate shape.

In the square battery, the battery case is in electrical contact with the electrolyte. Further, the battery case made of metal has higher rigidity than the exterior body 11 formed of a laminate film. Therefore, the battery cell 10 having the above-described configuration is characterized in that the shape of the exterior body 11 is highly stable and the exterior body 11 has a potential. Further, since the prismatic battery has a highly rigid exterior body, when the prismatic battery is adopted as the battery cell 10, the battery cell 10 is directly connected to the module case 30 without using the holding body 20. It is preferable to adopt a configuration in which the two are arranged.

As shown in FIG. 3, the base portion 31 is provided with a pair of fixing portions 33 on both sides. The fixing portion 33 has a through-hole through which a bolt can be inserted, and the base portion 31 can be fixed to a frame or a case having a placement surface on which the battery module is placed. The fixing portion 33 has a cylindrical metal spacer, and the metal spacer is inserted into the through hole of the fixing portion 33. As described above, the base 31 has the opening 32 having at least one surface opened, and the unit module 2 is inserted from the open surface of the base 31. Note that the plurality of battery cells 10 included in the unit module 2 are disposed on the base portion 31 in such a posture that the respective wide surfaces are parallel to the main surfaces of the pair of end plates. In addition, the plurality of unit modules 2 are arranged on the base 31 with a gap therebetween so that a flow path for cooling air to flow between the unit modules 2 is formed. For example, by providing a rib for guiding the unit module 2 to a predetermined position on the inner wall of the base portion 31, the adjacent unit modules 2 can be arranged with a gap therebetween.

The cover part 34 can be connected to the base part 31 by a tapping screw or a locking structure. Further, the cover part 34 and the base part 31 have a blower opening for introducing cooling air into the module case 30. The cover part 34 shown in FIG. 1 thru | or FIG. 3 has the introducing | transducing part 35 which has a ventilation port on an upper surface side. Although not shown, the base 31 has a blower opening on the bottom side. In an embodiment of an aspect of the present invention, the cooling air is introduced from the air blowing port of the introduction part 35 located on the cover part 34 side, and the flow path is located between the plurality of unit modules 2 arranged in the module case 30. The air is exhausted from the air outlet on the base side. The cooling air cools the plurality of battery cells 10 via the holding body 20 of the unit module 2 and the like while flowing through the flow path positioned between the plurality of unit modules 2 arranged in the module case 30. In addition, it can also comprise so that cooling air may be introduce | transduced from the ventilation port on the base 31 side.

As shown in FIG. 1, a plurality of restraining members 50 are installed on a pair of end plates 40. The plurality of restraining members 50 extend along the first direction Y that is the stacking direction of the battery modules 1. The plurality of restraining members 50 are provided at positions that cover at least the corner portion on the cover portion 34 side with respect to the module case 30. The restraining member 50 disposed on the cover part 34 side includes a horizontal part 50 a extending along the upper surface of the cover part 34 and a vertical part 50 b extending along the side surface of the cover part 34. Further, the restraining member 50 in FIG. 1 includes flat plate portions 50 c provided at both ends in the extending direction of the restraining member 50. The flat plate portion 50 c is provided with a through hole for connecting the restraining member 50 to the end plate 40. The restraining member 50 is fixed to the end plate 40 via a screw inserted through the through hole of the flat plate portion 50c.

With this configuration, the horizontal portion 50a of the restraining member 50 can regulate the displacement of the cover portion 34 in the vertical direction (second direction Z). Further, the vertical portion 50 b of the restraining member 50 can restrict the displacement of the cover portion 34 in the left-right direction (third direction X). In addition, the displacement of the cover part 34 in the extending direction (first direction Y) of the restraining member 50 is regulated by a fastening structure via the pair of end plates 40. In the power supply device described above, the displacement restricting portion 51 that restricts the displacement of the cover portion 34 in the second direction Z and the third direction X can be configured by the horizontal portion 50 a and the vertical portion 50 b of the restraining member 50.

As shown in FIGS. 8 and 9, the power supply device according to an aspect of the present invention may include an exterior case 60 including a mounting surface on which the end plate 40 and the module case 30 of the battery module 1 are fixed. it can. The exterior case 60 includes a pair of case bodies having flanges, and the flanges are fixed to each other. The battery module 1 is disposed in the exterior case 60, and the case body and the base 31 of the module case 30 are fixed via the fixing portion 33 of the base 31 of the module case 30. The exterior case 60 has a flow path defined therein, and cooling air flows in through a blower or the like, cools the battery module 1 disposed inside, and then is exhausted to the outside. Yes. Further, the exterior case 60 has a contact portion 61 that contacts the restraining member 50, and suppresses the displacement of the cover portion 34 in the vertical direction (second direction Z) via the restraining member 50. It has become.

FIG. 10 shows a power supply device according to an aspect provided with a modified restraining member 50. As shown in FIG. 9, an inflow port may be provided at a position biased with respect to the arrangement of the battery modules 1 in the outer case 60 due to space restrictions. In the case of such a configuration, the battery module 1 arranged close to the inflow port or the outflow port has a relatively low temperature, but there is a problem that the cooling efficiency decreases as the distance from the inflow port or the outflow port increases. When a temperature difference occurs between the plurality of battery modules 1, there is a problem that a difference in battery characteristics occurs.

In the modification of FIG. 10, the air volume regulating portion 52 is provided in which the shape of the horizontal portion 50a of the restraining member 50 is formed such that the area becomes wider as the position is closer to the inflow port or the outflow port. In the power supply device of FIG. 12, the air volume regulating portion 52 of the restraining member 50 covers the air outlet provided in the module case 30 of the battery module 1, and the air outlet of the air outlet is arranged according to the position of the battery module 1. The opening area is adjusted. According to this configuration, it is possible to reduce temperature variations among the plurality of battery modules 1 while sharing the members constituting the battery module 1 such as the module case 30.

In the power supply device having the above-described configuration, the module case 30 is divided into two parts, a base 31 and a cover 34, in order to improve assemblability. Arise. In particular, the module case 30 is formed of resin for weight reduction. In the case of a resin member, the dimensions may change due to various factors such as deformation of the member and warpage during molding, in addition to manufacturing intersection. Therefore, it is necessary to connect the base 31 and the cover part 34 with a clearance. In addition, the connection between the resin members cannot be fixed with a large axial force because creep deformation increases. Therefore, simply connecting the cover part 34 and the base part 31 may cause the cover part 34 to be displaced when a relatively strong impact is applied to the module case 30. When the displacement of the cover portion 34 is increased, the relative position of the cover portion 34 to the base portion 31 is displaced, and there is a problem that the module case 30 is damaged due to stress applied to the connecting portion of the cover portion 34 and the base portion 31.

In the power supply device according to an aspect of the present invention, the displacement of the cover portion 34 can be suppressed by the restraining member 50 as described above. Therefore, the strength against vibration and impact can be improved. The base portion 31 having the fixing portion 33 is formed of a resin like the cover portion 34, but is fixed to a metal frame or a metal case, so that through a metal spacer or the like, It can be fixed with a relatively large axial force. Therefore, since the displacement of the base 31 is smaller than the displacement of the cover portion 34, the influence on the strength against vibration and impact is small.

In the above-described configuration, the structure in which the battery cell 10 is cooled by blowing cooling air between the unit modules 2 has been described. However, such a configuration is not necessarily required. FIG. 11 is a cross-sectional view of the power supply device according to the second embodiment of the present invention. In the power supply device of FIG. 11, cooling air is sent along the upper surface of the battery module 1. The battery module 1 in FIG. 11 has heat radiation fins 23 a located between the outer case 60 and the module case 30.

Specifically, the power supply device according to the second embodiment includes a unit module 2 of a modification shown in FIG. The unit module in FIG. 13 is provided with a cooling unit 23 having heat radiation fins 23a in order to improve the cooling efficiency of the heat transfer plate 21. In the unit module 2 of the modified example of FIG. 7, the holding body 20 has an opening formed at a position corresponding to the cooling part 23 of the heat transfer plate 21, and the radiating fins 23 a of the cooling part 23 are formed from the opening of the holding body 20. It is designed to protrude. By providing the heat radiating fins 23a on the heat transfer plate 21, the heat transferred from the battery cells 10 can be efficiently radiated to the outside.

The battery module 1 in FIG. 12 includes a modified unit module 2 including a heat transfer plate 21 having the cooling unit 23 illustrated in FIG. The battery module 1 of this modification includes a cover portion 34 having an opening on the upper surface. The opening of the cover part 34 is provided at a position corresponding to the cooling part 23 of the unit module 2 of FIG. 13 arranged in the base part 31, and the cooling part 23 can be led out of the module case 30 from the opening. ing.

The power supply device according to the second embodiment having the above-described configuration blows cooling air along the upper surface of the cover portion 34 of the battery module 1, so that the battery cell 10 housed in the module case 30 It can cool via the heat exchanger plate 21 which has 23a.

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 battery module, 2 unit module, 10 battery cell, 11 exterior body, 12 electrode tab, 20 holder, 21 heat transfer plate, 22 fitting part, 23 cooling part, 30 module case, 31 base part, 32 opening part, 33 Fixed part, 34 cover part, 35 introduction part, 40 end plate, 50 constraining member, 50a horizontal part, 50b vertical part, 50c flat plate part, 51 displacement restriction part, 52 air volume restriction part, 60 exterior case, Y first direction , Z second direction, X third direction

Claims

Placed along the first direction out of the first direction, the second direction, and the third direction, which are three directions orthogonal to each other, and placed perpendicular to the second direction A plurality of battery modules disposed on the surface, each battery module including a plurality of battery cells, and a module case made of resin that houses the plurality of battery cells and includes at least a base portion and a cover portion. And the base has an opening having an open surface that opens the second direction, and a fixing portion fixed to a mounting surface on which the battery module is disposed, and The plurality of battery modules connected to the opening so that the plurality of battery cells are positioned between the cover and the base in the second direction;
A pair of end plates disposed at both ends of the plurality of battery modules in the first direction;
A constraining member connected to the pair of end plates and extending along the first direction, the surfaces of the plurality of cover portions positioned in the second direction, and positioned in the third direction A restraining member including a displacement restricting portion that abuts against the surfaces of the plurality of cover portions;
A power supply device comprising:
The power supply device according to claim 1,
Further, the battery module, the pair of end plates, and the restraining member are provided with an exterior case having the placement surface described above,
The power supply apparatus according to claim 1, wherein the outer case includes a contact portion that contacts the displacement regulating portion.
The power supply device according to claim 1 or 2,
The module case includes an introduction portion that abuts on the displacement regulating portion and has an air blowing port for introducing cooling air into the module case.
The power supply apparatus according to claim 1, wherein the displacement restricting portion includes an air volume restricting portion that partially closes an air outlet of the introduction portion.
The power supply device according to claim 1 or 2,
Each battery module further includes a holding body that holds the plurality of battery cells, and a heat transfer plate disposed between the plurality of battery cells.
The power supply device according to claim 4,
The heat transfer plate has a fitting portion that fits with the holding body.
The power supply device according to claim 4,
The heat transfer plate includes a cooling unit having heat dissipating fins protruding from an end surface of the holding body,
The module case has an opening that exposes the cooling unit.