JP2011076779A - Battery pack and separator for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a separator for battery pack, capable of enhancing a heat dissipation while securing an insulation property, and to provide a battery pack with the separator. <P>SOLUTION: The battery pack includes a plurality of battery cells 20 and a plurality of separators 30 arranged between the plurality of battery cells 20 and pinching and assembling them 20. The separators 30 are made of metal having a plurality of protrusions 31, and an insulator 33 is arranged at a section where each protrusion 31 of the separator 30 is brought into contact with an adjacent battery cell 20. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a battery pack and a battery pack separator used for an in-vehicle power supply device.

  Conventionally, an in-vehicle power supply device is configured by connecting a plurality of battery cells with a resin separator interposed therebetween (for example, see Patent Document 1). In this type, since charging and discharging with a large current are repeated, the temperature of the battery rises and the battery pack is used in a high temperature environment, and it is necessary to cool the battery pack. Conventionally, in a power supply device with this configuration, in order to prevent short circuit between battery cells, a plurality of battery cells are sandwiched between resin separators, an insulator is provided to the entire battery pack, and insulation is ensured. A configuration in which a cooling air passage for allowing a cooling medium (air) to pass through the separator is formed and cooling air is blown into the cooling air passage by a fan or the like is considered.

JP 2004-362879 A

However, when a part or most of the surface of the battery cell is covered with a resin separator as in the past, the surface area of the battery cell that can dissipate heat is reduced, and the heat dissipation of the battery pack is hindered. There is.
In addition, the battery pack has been downsized in recent years, and the gap between the battery cells tends to be narrowed. When this narrow gap is provided by a separator made of resin, a cooling air passage must be formed on the separator and the cooling air must be pushed in, resulting in pressure loss due to ventilation resistance, and uneven temperature in the battery cell. There is a risk of being able to.
The present invention has been made in view of the above-described circumstances, and has a battery pack and a battery pack separator that can improve heat dissipation by providing air permeability to a narrow gap between battery cells while ensuring insulation. The purpose is to provide.

  In order to achieve the above object, the present invention provides a battery pack comprising a plurality of battery cells and a plurality of separators arranged between the plurality of battery cells and sandwiching the plurality of battery cells. Is made of metal having a plurality of convex portions, and an insulator is disposed at a portion where the convex portions of the separator are in contact with the adjacent battery cells.

  This structure is good also as a structure provided with the flat plate part by which the said separator closely_contact | adheres to the said battery cell, and the some convex part provided in the said flat plate part. The convex portions may be arranged in a staggered manner. Further, the convex portion may be formed by bending a metal member by repeating irregularities.

  Further, the present invention provides a battery pack separator disposed between a plurality of battery cells constituting a battery pack, the battery pack separator being in close contact with the battery cells. A flat plate portion and a plurality of convex portions provided on the flat plate portion, and an insulator is disposed at a portion where the convex portion of the separator is in contact with the adjacent battery cell, It is characterized by.

  Further, the present invention provides a battery pack separator that is disposed between a plurality of battery cells that constitute a battery pack and that is assembled by sandwiching the plurality of battery cells. It is formed by bending, and an insulator is disposed at a portion where the convex portion of the separator is in contact with the adjacent battery cell.

  According to the present invention, it is provided with a plurality of battery cells and a plurality of separators arranged between the plurality of battery cells and sandwiching the plurality of battery cells, and the separator is made of metal having a plurality of convex portions. In addition, since the insulator is disposed at a portion where the convex portion of the separator and the adjacent battery cell are in contact with each other, the heat dissipation of the battery pack can be improved and the insulation can be secured.

1 is an exploded perspective view of a battery pack according to a first embodiment. It is a disassembled perspective view of the battery cell and separator of FIG. It is a side view which shows the state by which the separator is arrange | positioned between battery cells. It is a disassembled perspective view of the battery pack concerning another embodiment. FIG. 4 is a view corresponding to FIG. 3 showing another embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view of the battery pack 10, and FIG. 2 is an exploded perspective view of battery cells and separators.
As shown in FIG. 1, the battery pack 10 is configured by arranging and fastening a plurality of battery cells 20 having the same shape. A separator 30 is interposed in a gap between adjacent battery cells 20. Further, end plates 3 and 3 are provided at both ends of the battery pack 10, and both ends of the battery pack are sandwiched between the end plates 3 and 3. Further, the battery pack 10 is provided with a plurality of fastening jigs 4 in parallel on the side surface side of the battery pack 10, the fastening jigs 4 are screwed to the end plate 3, and the battery cells 20 and separators 30 to be stacked are fixed. It is configured.

  The end plate 3 is formed by integral molding with metal or resin so that the end plate 3 can cover the end face of the battery block 10a formed by stacking the battery cells 20 and the separators 30. According to this configuration, the battery pack 10 may include the metal end plate 3 to improve the heat dissipation of the battery pack 10, or may include the resin end plate 3 to It can also be set as the structure which maintains the insulation of the pack 10 still more reliably. Further, a separator 30 is interposed between the end plate 3 and the battery cell 20 to improve the heat dissipation of the battery pack 10 and to maintain the insulation of the battery pack 10.

  Moreover, the end plate 3 is provided with a screw hole 3a for screwing the fastening jig 4, and the screw 6 is inserted into the screw hole 3a. Screw holes 4 a for receiving screws 6 are provided at both ends in the longitudinal direction of the fastening jig 4. According to this configuration, the battery pack 10 includes the end plates 3 and 3 on both end faces of the battery block 10a, the fastening jig 4 is extended on both side faces of the battery block 10a, and the fastening jig 4 and the end plate 3 are connected to each other. The battery block 10a is fixed by screwing.

  The battery cell 20 is a prismatic battery such as a nickel hydride storage battery or a lithium ion secondary battery formed in a thin, substantially rectangular parallelepiped shape. In an in-vehicle power supply device, a space where the power supply device can be mounted is limited, and downsizing of the power supply device is important. According to this configuration, by providing the square battery, the arrangement efficiency can be improved and the energy density per unit volume can be increased as compared with the case where the cylindrical battery is provided.

  The outer can 21 of the battery cell 20 is formed of a metal having excellent thermal conductivity. For example, it can be formed of aluminum, an aluminum alloy, or the like, and is configured to improve heat dissipation and cooling. In addition, the upper surface of each battery cell 20 is provided with an output terminal 5 provided so as to protrude from the outer can 21, and the output terminal 5 includes a positive electrode 23 and a negative electrode 24, and the positive electrode 23 and the negative electrode 24 are The battery cells 20 are provided at symmetrical positions in the longitudinal direction. According to this configuration, when the adjacent battery cells 20 are arranged side by side, the pair of side plates 21a and 21b extending in the longitudinal direction of the outer can 21 are alternately inverted and arranged so that the battery cells are connected in series. it can. Further, according to this configuration, the battery cells 20 can be connected to each other so as to easily increase the output voltage and increase the output power, and the wiring length connecting the connection terminals can be shortened. Can be reduced.

  Further, the output terminal 5 is configured such that the cross-section is bent into a substantially L shape, and when the battery cells 20 are arranged so that the positive and negative of the adjacent battery cells 20 are reversed as described above, the adjacent battery cells are arranged. 20 output terminals 5 are provided so as to bend in opposite directions, and are connected to the surface of the output terminal 5 that is substantially parallel to the upper surface of the battery cell 20 and laminated with the output terminal 5 of the adjacent battery cell 20. The connecting bolt (not shown) is inserted into the bolt hole 5a, and the positive electrode 23 and the negative electrode 24 between the adjacent battery cells 20 are directly connected.

As shown in FIG. 2, a metal separator 30 is provided between adjacent battery cells 20. The separator 30 has a high thermal conductivity, is excellent in heat dissipation, and is formed of a lightweight and inexpensive member. For example, it can be formed of a metal such as aluminum or an aluminum alloy. A plurality of convex portions 31 are formed integrally with the separator 30 on one surface of the separator 30. The convex portion 31 can be formed on the separator 30 by casting or die casting, and the separator 30 can be produced in large quantities.
The other surface of the separator 30 is a flat plate surface 32 formed in a flat plate shape. The flat plate surface 32 has a thickness of about 1 mm and is formed in the same area as the side plates 21 a and 21 b of the battery cell 20. The separator 30 is disposed such that the flat plate surface 32 is in close contact with the entire surface of the side plate 21a or 21b of the battery cell 20. As will be described later, the thickness of the flat plate surface 32 is a dimension determined from the overall length of the battery pack 10 and is determined by the sum of the height of the protrusions 31, but is preferably 1 mm or less.

FIG. 3 is a side view showing a state in which the separator 30 is disposed between the battery cells 20.
An insulator 33 is provided and configured at a portion of the separator 30 where the adjacent battery cell 20 and the convex portion 31 are in contact with each other. The insulator 33 is formed of a resin having high insulating properties and excellent heat resistance. Moreover, it is good also as a structure formed with the thermal radiation insulation material which combines insulation, heat resistance, and heat conductivity. The insulator 33 is configured to be provided at the tip of the convex portion 31 provided on the separator 30 from the viewpoint of productivity. The insulator 33 may include the insulator 33 by dipping the tip of the protrusion 31 in a liquid or gel insulator and fixing the insulator attached to the tip of the protrusion 31. Alternatively, the surface of the separator 30 on which the convex portion 31 is provided is pressed against the insulating sheet formed in a sheet shape, and the insulator is cut out in the shape of the tip portion of the convex portion 31, and the tip portion of the convex portion 31 is cut. You may prepare so that the insulator 33 may adhere. The insulator 33 may not be provided at the tip of the convex portion 31 of the separator 30. For example, the insulator 33 may be provided on the side plate 21 a or 21 b of the battery cell 20.

  Further, as shown in FIG. 3, the battery cell 20 is assembled so as to be sandwiched by metal separators 30 from both sides, and a cooling medium (air) is poured into the surface of the separator 30 on which the convex portions 31 are formed. Convection cooling (convection cooling) can be performed. Thus, since the separator 30 is closely attached to the outer can 21 of the battery cell 20 having excellent thermal conductivity, the heat of the battery cell 20 is efficiently conducted to the separator 30 and the cooling of the battery cell 20 is promoted. According to this configuration, the metal separator 30 is provided so as to cover the entire surface of the side plate 21a or 21b of the battery cell 20, and the surface area of the separator 30 is utilized to the maximum, and the protrusion 31 and the battery By providing the insulator 33 at the site where the cell 20 comes into contact, the insulation between the battery cells 20 can be maintained, and the battery cells 20 can be prevented from coming into contact with each other and short-circuiting.

  The convex portion 31 provided on one surface of the separator 30 serves as a cylindrical pin fin, and is provided by making the maximum use of the surface area of the separator 30 formed in the same area as the side plates 21a and 21b of the battery cell 20. It has been. When the size of the side plates 21a and 21b is 80 mm in length and 130 mm in width, the diameter of the protrusion 31 is 3 mm, the height is 3 mm, and the distance between the protrusion 31 and the adjacent protrusion 31 is 3 mm. In addition, 280 convex portions 31 can be provided on one surface of the separator 30. In this case, compared with the case where the side plates 21a and 21b of the battery cell 20 are flat surfaces, the surface area can be 1.58 times larger, and the separator 30 is formed of a member having high thermal conductivity and excellent heat dissipation. Therefore, the heat dissipation of the battery cell 20 can be improved, and the cooling efficiency by convection cooling can be increased.

  Moreover, since the convex part 31 is provided in the whole surface of the separator 30, the separator 30 becomes strong to the load from a horizontal direction, and even when the battery cell 20 expand | swells, battery cells 20 contact each other and short-circuit. Can be prevented. The distance between the diameter of the convex portion 31 and the convex portion 31 adjacent to the convex portion 31 can be large or small in the manufacturable range of the separator 30, and the height of the convex portion 31 is also determined by the battery cell. It can be expanded and contracted by a distance of an effective gap interval between 20. In this case, of course, the effective heat radiation area varies depending on the diameter, distance, and height of the convex portion 31. As the height of the convex portion 31 is higher, a surface area of 1.58 times or more can be secured, but the current length is 3 mm as viewed from the overall length of the battery pack 10. Incidentally, when the height of the convex portion 31 is 5 mm, the diameter of the convex portion 31 is 3 mm, and the distance between the convex portions 31 is 3 mm, the surface area can be 2.09 times larger in calculation.

Although the convex part 31 is good also as a structure arranged in series with the separator 30, in this embodiment, the convex part 31 is arranged and comprised in zigzag form. According to this configuration, it is possible to increase the degree of turbulent flow around the convex portion 31 of the cooling medium (air) flowing through the passage formed by the convex portion 31 in the gaps between the plurality of battery cells 20 and to increase the cooling efficiency. Therefore, the heat dissipation of the battery cell 20 can be further improved.
Moreover, according to this structure, even if natural convection cooling is performed depending on use conditions, sufficient heat dissipation of the battery cell 20 can be ensured, and it is necessary to attach a blower such as a fan for forcibly blowing air. In addition, the cost can be reduced and the maintenance labor can be reduced.

  As described above, according to the present embodiment, the battery pack 10 is arranged between the plurality of battery cells 20 and the battery cells 20 and is assembled with the plurality of battery cells 20 interposed therebetween, and has high thermal conductivity and excellent heat dissipation. Since the separator 30 includes a plurality of metal separators 30, the separator 30 includes a plurality of protrusions 31, and the insulator 33 is provided at a portion where the protrusions 31 and the battery cells 20 come into contact with each other. In addition, the insulating property can be ensured.

Next, another embodiment will be described.
FIG. 4 is an exploded perspective view of the battery pack 50, and FIG. 5 is a side view showing a state in which the separator of this embodiment is disposed between battery cells.

In the present embodiment, the same members as those in the above-described embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
In the present embodiment, the separator 60 is formed in a corrugated shape by bending a light and inexpensive member having high thermal conductivity, excellent heat dissipation, and repeating unevenness. For example, it can be formed of a metal such as aluminum or an aluminum alloy, and can be mass-produced by forming by press molding or the like. According to this configuration, the separator 60 can be formed by bending a sheet metal by press forming, can be easily manufactured, and the surface area for radiating heat can be made wider than the surface area of the battery cell 20. Can be improved.

  Further, as shown in FIG. 5, the separator 60 includes an insulator 62 provided at a portion where the separator 60 and the adjacent battery cell 20 are in contact with each other. The insulator 62 is preferably made of a highly insulating resin or the like, and further preferably made of a heat dissipating insulating material having both insulating properties and thermal conductivity. The insulator 62 may be provided by applying a liquid or gel-like insulating paint with a brush or the like. According to this configuration, insulation between the battery cells 20 can be maintained, and safety can be ensured.

  As described above, according to the present embodiment, the separator 60 is formed by bending a sheet metal member such as aluminum or aluminum alloy having high thermal conductivity and excellent heat dissipation, and the separator 60 and the adjacent battery cell 20 are in contact with each other. Since the structure is provided with the insulator 62, the heat dissipation of the battery pack can be improved and the insulation can be ensured. Moreover, since the separator 60 can be formed by sheet metal press molding, the productivity is good.

As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to this. In the present embodiment, the separator 30 or the separator 60 is formed to have the same area as the side plate 21a or 21b of the battery cell 20, but the separator 30 or the separator 60 is formed in a frame shape. It is good also as a structure which covers not only the side surface of the battery cell 20, but the upper surface and the bottom surface, and also the corner part of the battery cell 20. According to this configuration, the strength of the separator can be increased so that the separator can be opposed to the expansion of the battery cell 20, and the configuration in which the corner portion of the battery cell is covered can reduce the impact from the outside of the battery cell. Resistance can be increased.
Further, in the present embodiment, the output terminal 5 provided in the battery cell 20 is provided so that the cross section is substantially L-shaped, the output terminals 5 of adjacent battery cells 20 are stacked, and fastened with a bolt. However, it is not limited to this, It is good also as a structure which connects an adjacent battery cell with a metal bus bar, and connects a battery cell in series.
Of course, other details and the like can be arbitrarily changed.

DESCRIPTION OF SYMBOLS 3 End plate 4 Fastening jig 5 Output terminal 10 Battery pack 20 Battery cell 21 Exterior can 21a Side plate 21b Side plate 22 Upper surface 23 Positive electrode 24 Negative electrode 30 Separator 31 Convex part 32 Flat plate surface 33 Insulator 50 Battery pack 60 Separator 62 Insulator

Claims (6)

A plurality of battery cells;
A battery pack comprising a plurality of separators arranged between the plurality of battery cells and assembled across the plurality of battery cells,
The separator is made of metal having a plurality of convex portions, and an insulator is disposed at a portion where the convex portions of the separator are in contact with the adjacent battery cells,
A battery pack characterized by A flat plate portion in which the separator is disposed in close contact with the battery cell;
A plurality of convex portions provided on the flat plate portion;
Providing
The battery pack according to claim 1. The convex portions are arranged in a staggered manner,
The battery pack according to claim 1 or 2. The convex part is formed by bending a metal member repeatedly with irregularities,
The battery pack according to claim 1. A battery pack separator disposed between a plurality of battery cells constituting a battery pack and assembled with the plurality of battery cells sandwiched therebetween,
A flat plate portion in which the battery pack separator is disposed in close contact with the battery cells;
It is made of metal having a plurality of convex portions provided on the flat plate portion, and an insulator is disposed at a portion where the convex portions of the separator are in contact with the adjacent battery cells,
A battery pack separator. A battery pack separator disposed between a plurality of battery cells constituting a battery pack and assembled with the plurality of battery cells sandwiched therebetween,
The battery pack separator is formed by repeatedly bending a metal member with irregularities,
Arranging an insulator at a portion where the convex portion of the separator and the adjacent battery cell are in contact with each other;
A battery pack separator.

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