JP2000251953A - Collective sealed secondary battery - Google Patents

Abstract

(57) [Problem] To provide a collective sealed secondary battery in which air pools are formed in meandering flow passages of water cooling jacket portions on both sides to prevent a decrease in cooling capacity. SOLUTION: A plurality of single cells, each having a power generating element housed in a bottomed rectangular cylindrical battery case and sealing an opening thereof, are arranged in series with a space 18 provided between the single cells, Cooling medium passages 21 are disposed on both sides of the battery in the arrangement direction, and rectifying ridges 41 are formed so as to form meandering flow passages 40 in the cooling medium passages 21. An air release port 43 is formed between the upper end 41a of the rectifying ridge 41 hanging from the upper end wall 42 of the cooling medium passage 21 and preferably at least the air release port 43 of the upper end wall 42 of the cooling medium passage 21. An inclined surface 44 that is inclined upward toward the side is formed in the opposing portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an integrated sealed secondary battery in which a plurality of cells are arranged in series to form an integrated battery case.

[0002]

2. Description of the Related Art As a collective type sealed secondary battery of this kind,
The one disclosed in Japanese Patent Application Laid-Open No. 7-85847 is known. As shown in FIG. 10, the assembled sealed secondary battery 61 accommodates a power generating element in a battery case 63 formed in a rectangular tube shape with a bottom, and seals an opening of the battery case 63 with a lid 64. A plurality of unit cells 62 are arranged in series, and the battery case 63 of the unit cells 62 is tightly connected by an end plate 65 and a restraining band 66. Also, a positive terminal 67 and a negative terminal 68 of each unit 62 are provided. Are made to penetrate through the lid 64 and protrude upward, and these terminals 67 and 68 are sequentially connected in series by an electric connection bar 69.

Japanese Unexamined Patent Publication (Kokai) No. 6-215804 discloses a monoblock storage battery in which a plastic battery case and a lid are heat-welded to each other on the outer surfaces of two opposed side walls of the battery case. A cooling jacket is formed between the side wall of the battery case and the side plate by heat-welding the side plate formed with the cooling plate, and an inlet orifice and an outlet orifice for the cooling liquid are provided on both ends of the side plate. . Also,
Within the cooling jacket portion, straightening ridges are provided alternately from the upper end surface and the lower end surface so as to form a meandering flow passage,
Further, an air escape port of about 1 to 3 mm is formed between the upper end face of the straightening ridge hanging from the upper end face and the upper end face.

[0004]

However, in the collective sealed secondary battery disclosed in Japanese Patent Application Laid-Open No. H7-85847, since the cells are closely arranged and tightened, when the ambient temperature is high or a large current is applied. When charging and discharging, there is a problem that heat is not sufficiently released from each unit cell, and the battery temperature rises and the battery life is shortened.

On the other hand, in the storage battery disclosed in Japanese Patent Application Laid-Open No. 6-215804, since both sides of the battery case are cooled by the water cooling jacket, the temperature rise can be suppressed to some extent. Is formed, it is possible to substantially uniformly cool the entire side surface of the battery case,
Furthermore, since an air escape hole is formed at the corner where the upper end wall of the water cooling jacket portion and the rectifying ridge are connected, it is possible to suppress the cooling capacity from being reduced to some extent by the air accumulation generated at the corner, but as described above. Similarly, there is a problem that the battery temperature rises because cooling between the cells cannot be performed.

As a result of research by the present inventor, a space was provided between cells in order to solve the problem of the collective type sealed secondary battery disclosed in JP-A-7-85847. In the case where the space is formed as a cooling passage, the flow of the cooling medium is particularly generated at the upper end wall of the water cooling jacket and the corner of the rectifying ridge. It has been found that since the air pool is easily generated due to stagnation, the deterioration of the cooling performance due to the generation of the air pool becomes a greater obstacle. Furthermore, it has been found that it is difficult to quickly exhaust the air along with the flow of the cooling medium simply by providing a small air vent at the corner, and it is not easy to eliminate the obstacle.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, the present invention provides a space serving as a cooling passage between cells, thereby effectively cooling each cell to prevent its temperature from rising, and providing a water cooling medium on both sides. It is an object of the present invention to provide a cluster-type sealed secondary battery in which the accumulation of air in a meandering flow passage is prevented from lowering the cooling capacity.

[0008]

Means for Solving the Problems The assembled sealed secondary battery of the present invention comprises a plurality of unit cells each having a power generating element housed in a bottomed rectangular cylindrical battery case and whose opening is sealed. Arranged in series,
In an assembled sealed secondary battery having a space between the cells, a cooling medium passage is provided on both sides of the unit cell in the arrangement direction of the cells, and a meandering flow passage is formed in the cooling medium passage. An air outlet is formed between the upper end of the rectifying ridge and the upper end wall of the cooling medium passage, which is provided with a rectifying ridge to protrude from an upper end of the cooling medium passage, and a space between the cells. Is a cooling medium passage communicating between the cooling medium passages on both sides, thereby effectively cooling each unit cell and preventing its temperature rise, and also providing a space between the unit cells as a cooling medium passage. Even if air easily accumulates in the corner between the upper end of the rectifying ridge and the upper end wall of the cooling medium passage, the air moves through the air release port to the meandering flow passage on the downstream side, and finally cools. Air is discharged from the media passage, so that air Mari cooling capacity generated can be reliably prevented.

In addition, when an inclined surface inclined toward the side is formed at least at a portion of the upper end wall of the cooling medium passage facing the air release port, even if air accumulates in the corner, the air passes through the air release port. Since it can be moved to the center side of the meandering flow passage on the inclined surface, it moves downstream by riding the strong flow of the cooling medium flowing in the meandering flow passage, and air accumulation occurs in the meandering flow passage and cooling capacity is reduced. It is possible to more reliably prevent the lowering.

If an inclined surface is formed on the upper end wall of the cooling medium passage, which is inclined upward from the inlet end to the outlet end of the cooling medium passage, the air sequentially passes through the air escape port along the inclined surface. And is smoothly discharged to the outlet end of the cooling medium passage.

If the height position of the upper end of the straightening ridge is made substantially the same and the opening area of the air outlet is gradually increased from the inlet end to the outlet end of the cooling medium passage, air flows out toward the downstream side. Therefore, it is possible to surely prevent the air from being discharged more smoothly and the cooling capacity from being reduced due to the generation of air pockets.

Further, even if an inclined surface is formed on the upper end wall of the cooling medium passage, which is inclined upward toward both sides from a portion facing each air outlet, air can be smoothly discharged.

The inclination angle of the inclined surface with respect to the horizontal plane is 3
When the vertical width of the air escape hole is 3 to 5 mm, the air collected in the corner between the upper end of the rectifying ridge and the upper end wall of the cooling medium passage can be reliably removed from the center of the meandering flow passage. The cooling capacity can be reliably prevented from being reduced due to the formation of air pockets.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a sealed secondary battery according to an embodiment of the present invention; FIG.

The assembled sealed secondary battery 1 of the present embodiment is a nickel-hydrogen secondary battery which can be suitably used as a drive power source for an electric vehicle. As shown in FIGS. 2 are connected in series and joined together to form an integrated battery case.
The plate-shaped cooling jacket member 3 having a flat space recessed inward on both sides thereof in the arrangement direction of the end plates 6 is joined, and a single lid 5 is joined thereon, thereby forming each unit cell. The end plate 6 and the end plate 6 are hermetically closed, and the end plate 6 is tightly tightened by a restraining band 7. Reference numeral 8 denotes a terminal mounting hole formed in the lid 5 so that a positive electrode terminal and a negative electrode terminal protruding upward from the cell 2 at one end and the other end penetrate, and 9 denotes a lid 5 corresponding to each cell 2. Is a safety valve mounting hole formed through. 10,
Reference numeral 11 denotes an inlet orifice and an outlet orifice for the cooling medium, which are integrally mounted on both ends of the lid 5. The cell 2, the cooling jacket member 3, the lid 5, the end plate 6, the inlet orifice 10, the outlet orifice 11, and the like are made of a synthetic resin such as a PP / PPE alloy, and are integrally joined to each other by welding. . In addition, adjacent cells 2 and 2
As shown in FIGS. 2 and 3, they are electrically connected by a connector 12.

The cell 2 will be described in detail below. As shown in FIGS. 2 and 3, a power generating element 15 is housed in a battery case 14 having a bottomed rectangular cylindrical shape. On the opposed wall surface 16 of the battery case 14 facing each other in a state of being arranged in series,
A large number of projections 17 that come into contact with each other are provided in a matrix, and these projections 17 form a space 18 serving as a cooling medium passage between the opposed wall surfaces 16. In addition,
An end plate 6 is applied to and joined to the opposing wall surfaces 16 outside the unit cells 2 at both ends of the unit cell row.
A space 18 is also formed between the two. Further, a plurality of (four in the illustrated example) protrusions 17 at appropriate locations are formed to have a large diameter, and engagement protrusions 19a and engagement recesses 19b which are fitted and engaged with each other are formed on the end faces thereof, so that the battery case 14 Positioning has been done. In addition, a joining edge portion 20 that abuts on the lower end edge portion at an appropriate distance from the upper end of the battery case 14 protrudes. Then, in a state where the cells 2 are arranged in series, the projecting portions 17 and the joining edges 20 which are in contact with each other are welded to each other, whereby the cells 2 are integrally joined as an integral battery case.

A cooling medium passage 21 is formed in a space formed between the unit cell 2 and the inner surface of the water-cooling jacket member 3 on both sides of the unit cell 2 in the arrangement direction. A distribution header forming gutter 22 is formed on the upper edge of the end plate 6 to communicate with the cooling medium passages 21 on both sides and distribute the cooling medium (water).

An upper frame 26 above the upper joining edge 20 in the battery case 14 of each unit cell 2 formed as an integrated battery case is provided with:
As shown in FIGS. 2, 3, and 4, substantially triangular cutouts 13 for arranging connecting bodies 12 for electrically connecting adjacent unit cells 2 are formed in a staggered manner. 1
3 and integrally joined to the battery case 14 and the lid 5 in a sealed state.

As shown in FIGS. 2, 3 and 5, the connecting body 12 is composed of a connecting shaft 27 made of metal (nickel or the like) and a support 28 made of synthetic resin. 28
Of the connection shaft 27 and the inner periphery of the holding cylinder portion 29 and are completely sealed by an O-ring 31 interposed between the flange portion 27a of the connection shaft 27 and the inner periphery of the holding cylinder portion 29. The support 28 has a pair of triangular wings 30 from a holding cylinder 29.
Are arranged so as to be joined to the upper frame 26 when the connecting body 12 is arranged in the notch 13.

As shown in FIGS. 2, 3 and 6, the lid 5 has an individual frame 32 formed on the inner surface thereof so as to correspond to the upper frame 26 of each battery case 14, and an inverted cross section on the outer peripheral portion. An outer peripheral frame 33 hangs down in an L-shape, and sealing ridges 34 are formed at both ends in the longitudinal direction and are joined to the upper ends of the distribution header forming gutters 22 to hermetically form the distribution header 35.

A terminal mounting hole 8 is formed on one side of both ends of the lid 5, and a connecting ridge 36 for connecting the inlet orifice 10 and the outlet orifice 11 is provided on the other side. . These orifices 10 and 11 have a plane shape of substantially J.
The connection port 38 is configured to protrude from the tip of the short side of the J-shaped box piece 37 having a U-shape and open at the bottom. In addition, the lid 5
A communication opening 39 communicating with the distribution header 35 is formed at a portion facing the long side end of the J-shaped box piece 37 of FIG.

As shown in FIG. 7, a meandering flow passage 40 meandering up and down is formed on the inner surfaces of both side walls of the cooling jacket member 3 so that the cooling medium flows evenly over the entire surface of the cooling medium passage 21. A rectifying ridge 41 is provided to protrude. An air outlet 43 is formed between the upper end 41 a of the rectifying ridge 41 hanging from the upper end of the cooling jacket 21 and the upper end wall 42 of the cooling jacket 21. Further, the upper end wall 42 of the cooling medium passage 21 is connected to its inlet end 2.
The thickness t2 on the outlet end 21b side is set to be smaller than the thickness t1 on the 1a side, whereby the inclined surface 44 inclined upward from the inlet end 21a of the coolant passage 21 toward the outlet end 21b on the upper end wall 42. Are formed. On the other hand, the height position of the upper end 41a of each straightening ridge 41 hanging from the upper end of the cooling medium passage 21 is set to be substantially the same height, so that the height dimension of the air release port 43 is reduced. D1, d2, d from the inlet end 21a toward the outlet end 21b
3 and d4. d1 to d4
Is preferably about 3 to 5 mm. The rectifying ridge 41
May be provided on the battery case 14 side of the cell 2.

In the assembled sealed secondary battery 1 having the above structure, when a cooling medium is supplied from the inlet orifice 10,
The refrigerant flows into the cooling medium passages 21 on both sides through the distribution header 35, flows in the cooling medium passage 21 toward the downstream side, and passes through the space 18 between the single cells 2 and between the two cooling medium passages 21, 21. However, the cooling medium is forcibly cooled on all sides including the opposed wall surface 16 of the battery case 14 of the unit cell 2, and the cooling medium is then discharged from the outlet orifice 11. Therefore, the four circumferential sides of all the cells 2 are effectively cooled by the cooling medium.

In the cooling medium passage 21,
Even if air accumulates in the corner between the upper end 41a and the upper end wall 42 of the rectifying ridge 41, the inclined surface 44 passes through the air escape port 43.
At the center of the meandering flow passage 44,
Moving on the downstream side with a strong flow of cooling medium flowing through
The air that did not get into the flow also passes through the air release port 43 along the inclined surface 44 in order, and the outlet end 21
b is discharged smoothly. Further, since the height dimension of the air release port 43 is gradually increased from the inlet end 21a to the outlet end 21b of the cooling medium passage 21 like d1 to d4, the opening dimension of the air release port 43 is sequentially increased. The air is more likely to flow out toward the downstream side, and is discharged from the cooling medium passage 21 more smoothly. Thus, the meandering flow passage 4
Thus, it is possible to reliably prevent the cooling capacity from being reduced due to the occurrence of air stagnation at zero.

Further, in this embodiment, the unit cells 2 are welded and integrally joined to each other to form an integrated battery case, and the integrated lid 5 is welded to the opening thereof and sealed. The assembled sealed secondary battery 1 having an integrated battery case can be obtained with a small number of parts and assembling man-hours. Further, the projecting portion 17 is formed on the opposed wall surface 16 of the battery case 14 of each cell 2. Are easily welded at low cost because they are welded to each other.
A cooling medium passage 18 can be formed over substantially the entire surface between 6 and 16.

Further, since the cooling medium passage 21 is formed by joining the compact plate-shaped cooling jacket members 3 to both sides of the unit cell array, the weight can be reduced.

Further, an inlet orifice 10 and an outlet orifice 11 of a cooling medium for supplying and discharging the cooling medium to and from the cooling medium passage 21 are disposed at both ends in the unit cell arrangement direction, and the cooling headers on both sides are arranged via a distribution header 35. Since it is connected to the medium passage 21, the entire periphery of all the cells 2 can be effectively cooled by a single cooling medium path in combination with the above configuration.

In the configuration example of the cooling medium passage 21, the upper end wall 42 has the inlet end 21a and the outlet end 21a.
The inclined surface 44 is formed so as to be inclined over b.
As shown in FIG. 8, on the upper end wall 42 of the cooling medium passage 21,
The inclined surface 44 may be formed so as to be inclined upward toward both sides from a portion facing each air release port 43. Also in this case, the upper end wall 42 of the cooling medium passage 21 and the straightening ridge 41
Can be reliably moved to the center side of the meandering flow passage 40, and can be discharged with a strong flow of the cooling medium. It is possible to prevent the cooling capacity from being reduced. In addition, the height dimension of the air release port 43 is 3 to 5 mm.
The inclination angle θ of the inclined surface 43 with respect to the horizontal plane is preferably about 3 to 5 °.

Next, another embodiment of the collective sealed secondary battery of the present invention will be described with reference to FIG. In the above embodiment, the lid 5 covers the end plate 6 and the entrance orifice 1
In the present embodiment, the cover 5 covers only the unit cells 2 and the distribution header 52 is provided at the upper end of the end plate 6 at both ends. A connection part which is provided integrally and has an inlet orifice 10 and an outlet orifice 11 projecting from the upper surface thereof, and connecting the internal cooling medium passage 21 to both ends of the distribution header part 52 at the upper ends of both ends of the cooling jacket member 3. 53 is bent. Also,
The hatched portion in FIG. 9 is the assembly of the unit cells 2 and the welded portion 54 of the cooling jacket member 3.

In this embodiment, basically, the same operation and effect as those of the above embodiment can be obtained.

Further, in the above-described embodiment, an example has been shown in which the constituent members are integrally joined by welding, but they may be integrally joined with an adhesive.

[0032]

According to the collective sealed secondary battery of the present invention,
As is clear from the above description, a plurality of cells each containing a power generating element in a bottomed rectangular cylindrical battery case and sealing the opening thereof are provided, and a space is provided between the cells to form a series. The cooling medium passages are arranged on both sides in the arrangement direction of the unit cells, and rectifying protrusions are formed so as to form a meandering flow passage in the cooling medium passage. An air outlet is formed between the upper end of the rectifying ridge and the upper end wall of the cooling medium passage, so that the space between the cells becomes a cooling medium passage communicating between the cooling medium passages on both sides. In addition, each cell can be effectively cooled to prevent its temperature from rising, and even if air easily accumulates in the corner between the upper end of the rectifying ridge and the upper end wall of the cooling medium passage, the air escapes. Through the port to a meandering flow passage downstream and ultimately Is exhausted from the cooling capacity air pocket occurs serpentine flow path can be reliably prevented.

Further, when an inclined surface inclined toward the side is formed at least at a portion of the upper end wall of the cooling medium passage facing the air release port, even if air is trapped at the corner, the air passes through the air release port. Since it can be moved to the center side of the meandering flow passage on the inclined surface, it moves downstream by riding the strong flow of the cooling medium flowing in the meandering flow passage, and air accumulation occurs in the meandering flow passage and cooling capacity is reduced. It is possible to more reliably prevent the lowering.

When an inclined surface is formed on the upper end wall of the cooling medium passage, which is inclined upward from the inlet end to the outlet end of the cooling medium passage, the air sequentially passes through the air escape port along the inclined surface. And is smoothly discharged to the outlet end of the cooling medium passage.

If the height position of the upper end of the straightening ridge is made substantially the same and the opening area of the air outlet is gradually increased from the inlet end to the outlet end of the cooling medium passage, air flows out toward the downstream side. Therefore, it is possible to surely prevent the air from being discharged more smoothly and the cooling capacity from being reduced due to the generation of air pockets.

Further, even if an inclined surface is formed on the upper end wall of the cooling medium passage, which is inclined upward toward both sides from a portion facing each air outlet, air can be smoothly discharged.

The inclination angle of the inclined surface with respect to the horizontal plane is 3
When the vertical width of the air escape hole is 3 to 5 mm, the air collected in the corner between the upper end of the rectifying ridge and the upper end wall of the cooling medium passage can be reliably removed from the center of the meandering flow passage. The cooling capacity can be reliably prevented from being reduced due to the formation of air pockets.

[Brief description of the drawings]

FIG. 1 is an external perspective view of an embodiment of a collective sealed secondary battery of the present invention.

FIG. 2 is a vertical sectional side view of the embodiment.

FIG. 3 is a partial vertical sectional front view of the embodiment.

FIG. 4 is a partial perspective view of an upper end portion of the unit cell group of the embodiment.

FIG. 5 is a perspective view of the electric connection body of the embodiment.

FIG. 6 is a perspective view of the lid according to the embodiment.

FIG. 7 is a longitudinal sectional view showing a configuration inside a cooling medium passage of the embodiment.

FIG. 8 is a longitudinal sectional view showing another example of the configuration inside the cooling medium passage of the embodiment.

FIG. 9 is an exploded perspective view of another embodiment of the collective sealed secondary battery of the present invention.

FIG. 10 is a front view of a conventional collective sealed secondary battery.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Set-type sealed secondary battery 2 Single cell 18 Space part 21 Cooling medium passage 21a Inlet end 21b Outlet end 40 Meandering flow passage 41 Straightening ridge 41a Upper end 42 Upper end wall 43 Air escape port 44 Slope

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shinsuke Fukuda 555 Sakaijuku, Kosai-shi, Shizuoka Prefecture Inside Panasonic EV Energy Co., Ltd. (72) Inventor Shinichi Yuasa 555 Sakaijuku, Kosai-shi, Shizuoka Prefecture Inside Panasonic EV Energy ( 72) Inventor Shinji Hamada 555 Sakaijuku, Kosai-shi, Shizuoka Prefecture F-term in Panasonic EV Energy Co., Ltd. (reference) 5H020 AA04 AS06 CC06 HH00 HH01 KK13 5H031 AA09 HH00 HH08 KK08

Claims (7)

[Claims] 1. A set in which a plurality of unit cells each containing a power generating element housed in a bottomed rectangular cylindrical battery case and sealing an opening thereof are arranged in series, and a space is provided between the unit cells. In the sealed type secondary battery, cooling medium passages are arranged on both sides of the unit cell in the arrangement direction, and rectifying ridges are formed so as to form a meandering flow passage in the cooling medium passage. A sealed secondary battery having an air outlet formed between an upper end of a rectifying ridge hanging down from an upper end portion and an upper end wall of a cooling medium passage. 2. The rechargeable sealed secondary battery according to claim 1, wherein an inclined surface inclined toward the side is formed at least in a portion of the upper end wall of the cooling medium passage facing the air release port. . 3. The collective sealed secondary battery according to claim 1, wherein an inclined surface which is inclined upward from an inlet end to an outlet end of the cooling medium passage is formed on an upper end wall of the cooling medium passage. . 4. The cooling device according to claim 1, wherein the height of the upper end of the straightening ridge is substantially the same, and the opening area of the air outlet is gradually increased from the inlet end to the outlet end of the cooling medium passage. 2. The collective sealed secondary battery according to 1. 5. The collective hermetic secondary according to claim 1, wherein an inclined surface is formed on an upper end wall of the cooling medium passage, and the inclined surface is inclined upward toward both sides from a portion facing each air release port. battery. 6. The inclination angle of the inclined surface with respect to the horizontal plane is 3-5.
6. The collective sealed secondary battery according to claim 2, 3 or 5, wherein 7. The collective sealed secondary battery according to claim 1, wherein a vertical width of the air vent is 3 to 5 mm.