JP2012094371A - Battery pack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery pack which is capable of effectively cooling batteries by air cooling.SOLUTION: In a battery pack 10 which is constituted by arranging a plurality of batteries 1 with separators 7 having insulating properties therebetween and blows cooling air between the batteries 1 to cool the batteries 1, wire-shaped inlet turbulence promoting bodies 11 having insulating properties are disposed at intervals in an inlet and an outlet through which the cooling air flows between the batteries 1. The separators 7 have projections and recesses, and cavities are formed between the separators 7 and the batteries 1 correspondingly to the projections and recesses.

Description

  The present invention relates to an assembled battery for in-vehicle use, for example.

  For example, an assembled battery for on-vehicle use or the like, which is configured by arranging a plurality of batteries, and that cools the battery by air cooling by blowing cooling air between these batteries, is known. In this type of battery, for example, a rectangular battery including a winding electrode having a curved surface in part, and a rectangular case having thermal conductivity and containing the winding electrode, and at least a part of the inner surface of the rectangular case is An assembled battery formed in a shape along the curved surface of the wound electrode has been proposed (see, for example, Patent Document 1), and the surface area of the cooling surface is increased to effectively cool the square battery without increasing the size. Techniques to do this have been proposed.

JP 2009-110732 A

However, in the conventional configuration, although the surface area of the cooling surface is increased, there is a problem that the cooling air flow for cooling the prismatic battery becomes a problem and cannot be effectively cooled.
Accordingly, an object of the present invention is to provide an assembled battery that can solve the above-described problems of the prior art and can effectively cool the battery by air cooling.

The present invention is configured by arranging a plurality of batteries with an insulating separator interposed therebetween, and in an assembled battery in which cooling air is blown between the batteries to cool the batteries, cooling between the batteries is performed. The present invention is characterized in that a wire-like inlet turbulence promoter having insulating properties is disposed at the wind inlet.
In this invention, since the wire-like inlet turbulence promoter is disposed at the inlet portion of the cooling air between the batteries and / or the separator is provided with the protrusion, the cooling air passing through the inlet turbulence promoter becomes turbulent. The battery surface is cooled by this turbulent effect, and the cooling effect is promoted.
Further, the present invention is configured by arranging a plurality of batteries with an insulating separator interposed therebetween, and in the assembled battery for cooling the batteries by blowing cooling air between the batteries, the separator is recessed. In addition, there are projections, and voids are formed between the cells corresponding to the depressions and projections, and insulating projections that protrude into the voids are arranged at intervals in the depth direction of the voids. It is characterized by that.

In this case, it is good also as a structure which arrange | positions the said wire-shaped inlet turbulence promoter at the said inlet part at intervals up and down.
In addition, the separator has a concave and a convex, and a space is formed between the battery and the concave and convex so as to correspond to the concave and convex, and the protrusion protruding into the void is spaced in the depth direction of the void. May be arranged. The protrusion may be disposed at a position immediately before the turbulent flow from the upstream changes to a laminar flow. The separator has a concave and a convex, and a space is formed between the battery corresponding to the concave and convex, and the wire-like internal turbulence is promoted so as to penetrate the concave and convex in the void vertically. A plurality of bodies may be arranged at intervals in the depth direction of the space.
Further, the internal turbulence promoting body may be disposed at a position immediately before the turbulent flow from the upstream changes to a laminar flow.

  Here, when a wire-like inlet turbulence promoting body is disposed at the inlet portion of the cooling air or a protrusion is provided on the separator, the cooling air enters as a turbulent flow between the batteries, but eventually becomes a laminar flow. According to the above configuration, since the protrusions that make the laminar flow turbulent and the internal turbulence promoting body are arranged at appropriate intervals just before the laminar flow, there is always turbulent flow between the batteries. Occurs, and the cooling effect in the depth direction of the battery is uniformly promoted.

  According to the present invention, since the wire-like inlet turbulence promoting body is disposed at the inlet portion of the cooling air between the batteries and / or the separator is provided with the protrusion, the cooling air passing through the inlet turbulence promoting body is turbulent. And the battery surface is cooled by this turbulent effect, and the cooling effect is promoted.

It is an external appearance perspective view which shows the assembled battery which concerns on one embodiment of this invention. It is the same top view. It is the same side view. It is a perspective view which shows a separator. A is a front view schematically showing a recess of a separator, and B is an end view. A is a figure which shows an aspect ratio and turbulent flow length, B is a figure which shows a measurement result. It is a figure which shows the relationship between protrusion height and flow path height. It is a figure which shows the relationship between protrusion width and flow path width. A to D are views showing the arrangement relationship of protrusions. It is a figure which shows the relationship between a flow velocity and turbulent flow length. It is a perspective view which shows an assembled battery typically. It is sectional drawing which shows a separator. It is a perspective view which shows another embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view of an assembled battery 10 according to the present embodiment, and FIG. 2 is a plan view thereof.
The assembled battery 10 is configured by stacking a plurality of batteries (cells) 1 back and forth on a heat insulating plate 2. The battery (cell) 1 is a thin rectangular battery that is thinner than its width. The positive electrode and the negative electrode that are output terminals 4 are spaced apart from the top surface, which is the first surface of the chamfered rectangular case 3, and protruded. ing. In the battery 1 of FIGS. 1 and 2, positive and negative output terminals 4 are projected and fixed at both end portions of the upper surface. The position where the output terminal 4 protrudes is a position where the positive electrode and the negative electrode are symmetrical. Thereby, when the battery 1 is turned upside down and stacked, the positive electrode and the negative electrode can be stacked, and series connection can be easily performed. A winding electrode (not shown) is built in the rectangular case 3. As the battery 1, a secondary battery such as a lithium ion battery, a nickel metal hydride battery, or a nickel cadmium battery can be used. In particular, a lithium ion battery is preferable because it has a high output per unit volume and is suitable for miniaturization and high output. A primary battery can also be used.

  Each of the output terminals 4 is bent in an L-shaped cross section, and a connecting hole is opened in the bent portion, and the bent portions stacked on each other can be connected by inserting a connecting bolt into the connecting hole. . In particular, the positive and negative output terminals 4 are bent in opposite directions as shown in FIG. 2, and the positive and negative output terminals 4 are alternately bent in opposite directions between adjacent batteries 1. These output terminals 4 are formed in a size and shape that can be directly connected between adjacent batteries 1. Thereby, a positive electrode and a negative electrode are directly connected between adjacent batteries, and a plurality of batteries are connected in series. However, the output terminal 4 can also connect the bus bar of a metal plate, and can connect the adjacent battery 1 in series.

  The end of the assembled battery 10 is connected to a control circuit (not shown), and the control circuit measures the voltage, current, temperature, etc. of each battery 1 to determine the battery capacity and the required charge / discharge amount. Etc. are controlled. The power supply device connecting the batteries 1 in series can increase the output voltage by increasing the output voltage. However, the power supply device can also connect the batteries 1 in parallel and in series. An end plate can also be disposed at the end of the assembled battery 100.

  This battery 1 is formed with terminal ribs that stand upright so as to surround the periphery of the output terminal 4, thereby preventing an accidental diffusion even if the electrolyte inside the outer can leaks from the periphery of the output terminal. Is done. In the rectangular case 3, a wound electrode (not shown) is inserted from an opening portion of a bottomed cylindrical outer can and an electrolyte solution is injected. Then, the opening portion is closed with a sealing plate and sealed by laser welding or the like. The rectangular case 3 is made of a metal having excellent thermal conductivity. The sealing plate is provided with a safety valve. When the battery is charged / discharged in an abnormal state, the safety valve opens to discharge the electrolyte.

  Between each battery 1, the separator 7 which has insulation is arrange | positioned. The separator 7 is configured so that each battery 1 can be cooled by air cooling with an appropriate interval between the batteries 1 and cooling air flowing through the interval. Although illustration is omitted, a supply duct from a blower, for example, is connected to the one surface 10A side of the assembled battery 10, and cooling air supplied through the supply duct passes through a gap formed by each separator 7. It flows to the other surface 10B side and is exhausted to the outside through an exhaust duct (not shown) provided on the other surface 10B side. Thereby, the assembled battery 10 is cooled by air cooling.

  The separator 7 is, for example, a resin molded product manufactured by resin molding, and is configured by repeating a rectangular wave-shaped concave 7A, convex 7B, concave 7A, convex 7B. . These recesses 7A, 7B, 7A, 7B,... Extend parallel to each other, and correspond to these recesses 7A, 7B, 7A, 7B,. 8 are formed, and each of the voids 8, 8, 8... Penetrates from the one surface 10A side to the other surface 10B side of the assembled battery 10.

In the present embodiment, a wire-like inlet turbulence promoter 11, 11, 11,... Formed of an insulating material on the inlet side of the cooling air between the batteries 1, that is, on the one surface 10A side of the assembled battery 10, A plurality are arranged at intervals in the vertical direction. The inlet turbulence promoting bodies 11, 11, 11,...
The inlet turbulence promoting bodies 11, 11, 11... Are arranged corresponding to the recesses 7 A, 7 B, 7 A, 7 B..., And cross the center in the vertical direction of the cavities 8, 8, 8. Is arranged. When the inlet turbulence promoting bodies 11, 11, 11,... Are arranged at the inlet of the cooling air in this way, the cooling air that has passed through the inlet turbulence promoting bodies 11, 11, 11,. The cooling of the surface of the battery 1 is promoted by this turbulent flow effect.

  This turbulent flow eventually becomes a laminar flow as it travels between the batteries 1 toward the other surface 10B. Here, as shown in FIG. 4, on the wall surfaces of the recesses 7A, the protrusions 7B, the recesses 7A, the protrusions 7B... Of the separator 7 as shown in FIG. Projections 9, 9, 9... Made of an insulating material as a turbulence promoting body having a triangular projection shape such as a triangle shape or a quadrangular shape are integrally formed. The protrusions 9, 9, 9... May be arranged in a single line or in a double line along the flow of the cooling air. Alternatively, a staggered arrangement may be used. A concave shape or the like may be used as long as a turbulent flow can be formed instead of a protrusion. .. Are provided on the wall surfaces of the corresponding recesses 7A, protrusions 7B, recesses 7A, protrusions 7B,... At an appropriate interval L in the depth direction.

  When the inlet turbulence promoting body 11 is arranged at the inlet of the cooling air, the cooling air enters as a turbulent flow between the batteries 1 as described above, but eventually becomes a laminar flow. The protrusions 9, 9, 9... Are preferably arranged at an appropriate interval L at a position just before the cooling air becomes laminar, a position where the turbulent flow disappears, or the like. If it does so, a turbulent flow will always generate | occur | produce between the batteries 1, and the cooling effect over the depth direction of the battery 1 will be accelerated | stimulated uniformly.

5A and 5B schematically show the arrangement of the protrusions 9. The channel height H of the recess 7A, the height h of the projection 9, the channel width W of the recess 7A, the width w of the projection 9, and the interval L of the projection 9 are used. As shown in FIG. 6A, the present inventors varied the flow channel height H / flow channel width W = aspect ratio (H / W) in a range of H / W = 0.13 to 1, The length (turbulent flow length) in which the turbulent flow generated in the protrusion 9 continues downstream was measured, and the measurement result shown in FIG. 6B was obtained. From this result, it was found that the turbulent flow length is shortened when the aspect ratio (H / W) is 0.2 or less and 0.6 or more. Therefore, in order to lengthen the turbulent flow length, it is desirable to set 0.2 <H / W <0.6. This increases the turbulent flow region and enhances the heat transfer promoting effect. FIG. 7 shows the relationship between the flow path height H of the recess 7 </ b> A and the height h of the protrusion 9. The turbulent flow length was measured by changing the protrusion height h / flow path height H in various ways. From this result, it was found that the turbulent flow length becomes shorter at h / H = 50% or less. Therefore, in order to lengthen the turbulent flow length, it is desirable to set h / H = 50% or more, thereby increasing the turbulent flow region and enhancing the heat transfer promoting effect.
FIG. 8 shows the relationship between the flow path width W of the recess 7 </ b> A and the width w of the protrusion 9. The ratio of the vortex turbulent region in the channel of the recess 7A was measured by changing the protrusion width w / the channel width W in various ways. According to this result, it was found that turbulent flow was generated in a region of a maximum of 18% around the protrusion width w / channel width W = 0.1 to 0.15. Therefore, it is desirable to set 0.1 <w / W <0.15, the area ratio increases, and the heat transfer promoting effect is enhanced.

  FIG. 9 shows an arrangement example of the protrusions 9. FIG. 9A is an arrangement example of one protrusion 9, and FIGS. 9B to 9D are examples in which two protrusions 9 are arranged at different intervals. 9B to 9D, by arranging the second protrusion 9 in the turbulent flow region generated by the first protrusion 9, turbulent flow is effectively generated in the flow path. In this case also, it was found that the turbulent flow length becomes longer compared to the example of FIG. 9A. FIG. 10 shows the turbulent flow length (mm) on the vertical axis and the flow velocity (m / s) on the horizontal axis. The turbulence length is proportional to 1.3 times to 3.7 times the flow velocity. As a result of varying the aspect ratio (H / W) indicating the relationship between the channel height H and the channel width W (0.13 to 0.5) and measuring the relationship between the flow velocity and the turbulent flow length, It was found that the turbulent flow length was 10 to 40 (mm) when the flow rate was around 1 to 3 (m / s). When used for cooling the battery 1, an air flow rate of 0.5 to 4 (m / s) is sufficient, and the second protrusion 9 is provided in the turbulent flow region generated by the first protrusion 9. When arranged, since the turbulent flow length continues in the range of 10 to 40 (mm), it is desirable that the interval L between the protrusions 9 is also arranged at an interval of 10 to 40 (mm). Increases and the heat transfer promoting effect is enhanced.

FIG. 11 schematically shows the assembled battery 10 described above.
In this configuration, the assembled battery 10 is fixed in the fixed case 20, and both ends of the wire-like inlet turbulence promoting bodies 11, 11, 11... Are fixed to the pair of holding plates 21. The holding plate 21 is fixed between the vertical frames 20 </ b> A and 20 </ b> B of the fixed case 20. If comprised in this way, by providing the said wire-shaped inlet turbulence promoter 11, 11, 11, ..., the fixed case 20 will be reinforced strengthly and the robust assembled battery 10 can be comprised.

Next, another embodiment will be described.
In the above embodiment, a plurality of protrusions 9, 9, 9... Are provided on the wall surfaces of the recesses 7A, 7B, 7A, 7B,.
In this embodiment, the protrusions 9, 9, 9... Are omitted, and wire-like internal turbulence promoting bodies 31, 31, 31 are disposed as shown in FIG. In this internal turbulence promoting body 31, 31, 31..., The base ends are connected by a connecting plate 33 with an appropriate interval L between them, and the tips 31A, 31A, 31A. As shown in FIG. 4, the separator 7 having the same configuration as the separator 7 is disposed through the recesses 7A, 7B, 7A, 7B,. These internal turbulence promoting bodies 31, 31, 31... Are arranged for all the separators 7.

  When arranging with respect to all the separators 7, each connecting plate 33 is fixed to the upper surface of the rectangular case 3 by adhesion or the like with reference to FIG. 11. With this configuration, the internal turbulence promoting bodies 31, 31, By providing 31..., The fixed case 20 is reinforced in strength. The interval L is an interval at which the turbulent flow disappears, and it is desirable to set the interval L immediately before the turbulent flow becomes a laminar flow. According to this configuration, compared to the case where the protrusion 9 is provided, as shown in FIG. 12, the passage of the cooling air is formed all around the internal turbulence promoting bodies 31, 31, 31 ... A turbulent flow is formed without interfering with the cooling air, and a further cooling effect can be expected.

FIG. 13 shows another embodiment.
In this embodiment, the internal turbulence promoters 41, 41 entering the wave shape in the respective cavities 8, 8, 8 ... in succession to the inlet turbulence promoters 11, 11, 11 ... described above. , 41... Are arranged. The internal turbulence promoting bodies 41, 41, 41... Are also formed with turbulent flow without interfering with the cooling air because the cooling air passages are formed all around the internal turbulence promoting bodies 41, 41, 41. Similarly, a further cooling effect can be expected.

DESCRIPTION OF SYMBOLS 10 Assembly battery 1 Battery 2 Heat insulation plate 3 Rectangular case 4 Output terminal 7 Separator 7A Concave 7B Convex 8, 8, 8 ... Space 9, 9, 9 ... Protrusion 10 Assembly battery 11, 11, 11 ... Inlet turbulence promoter 20 Fixed case 31, 31, 31 ... Internal turbulence promoter

Claims (7)

  In an assembled battery in which a plurality of batteries are arranged with an insulating separator interposed therebetween, and cooling air is blown between these batteries to cool the batteries, an inlet portion for cooling air between the batteries An assembled battery, wherein a wire-like inlet turbulence promoting body having an insulating property is disposed on the battery pack.   In the assembled battery in which a plurality of batteries are arranged with an insulating separator interposed therebetween, and the battery is cooled by blowing cooling air between the batteries, the separator has a concave and a convex, A space is formed between the battery corresponding to the concave and convex portions, and protrusions having insulating properties protruding into the space are arranged at intervals in the depth direction of the space. Assembled battery.   2. The assembled battery according to claim 1, wherein a plurality of the wire-like inlet turbulence promoting bodies are arranged in the inlet portion with an interval in the vertical direction.   The separator has a recess and a protrusion, and a space is formed between the battery corresponding to the recess and the protrusion, and an insulating protrusion protruding into the space is spaced in the depth direction of the space. The assembled battery according to claim 1, wherein the battery pack is disposed with a gap.   The assembled battery according to claim 2 or 4, wherein the protrusion is disposed at a position immediately before the turbulent flow from the upstream changes to a laminar flow.   The separator has a concave and a convex, and a space is formed between the battery corresponding to the concave and convex, and the wire-like internal turbulence is promoted so as to penetrate the concave and convex in the void vertically. The assembled battery according to claim 1 or 3, wherein a plurality of bodies are arranged at intervals in the depth direction of the space.   The assembled battery according to claim 5, wherein the internal turbulence promoting body is disposed at a position immediately before the turbulent flow from the upstream changes to a laminar flow.