JP2008282648A - Assembled battery - Google Patents

Abstract

An assembled battery capable of reducing noise leaking to the outside is provided.
An assembled battery provided by the present invention is configured by arranging a plurality of chargeable / dischargeable cells in a predetermined direction. Between adjacent unit cells 20, a spacer 40 including a contact part 42 that contacts at least one of the unit cells and a non-contact part 44 that spreads in a planar shape without contacting any unit cell is interposed. It is disguised. The non-contact portion 44 is provided with a plurality of through holes 46, and voids 47 and 49 communicating with the through holes 46 are formed on both sides of the non-contact portion 44. According to this configuration, even if noise is generated from the unit cell 20, the noise is absorbed by using, for example, the through hole 46 of the non-contact portion 44 disposed on the right side of the unit cell and the gap 47 provided on the back surface thereof. In addition, noise leaking outside the assembled battery 10 can be suppressed.
[Selection] Figure 2

Description

  The present invention relates to an assembled battery in which a plurality of chargeable / dischargeable single cells (secondary batteries) are arranged in a predetermined direction (typically, an assembled battery in which the plurality of single cells are connected in series). Specifically, the present invention relates to an assembled battery suitable for mounting on a vehicle.

  Lithium ion batteries, nickel metal hydride batteries and other secondary batteries or capacitors and other storage elements are used as unit cells, and assembled batteries formed by arranging a plurality of unit cells are used as power sources for vehicles or as power sources for personal computers and portable terminals. The importance is increasing. In particular, an assembled battery in which a plurality of lithium-ion batteries that are lightweight and have a high energy density are connected in series as single cells is expected to be preferably used as a high-output power source for mounting on vehicles.

  In the assembled battery configured by arranging a plurality of unit cells in this way, heat is generated in each unit cell constituting the assembled battery when charging / discharging, so that the generated heat can be quickly cooled. In addition, it is required to ensure the heat dissipation of the assembled battery. As a method for meeting such a requirement, a method for promoting heat dissipation by providing a gap between adjacent unit cells is known. Patent Documents 1 to 3 are cited as prior art documents relating to this type of technology. For example, in the assembled battery described in Patent Document 1, a spacer (interval holding plate) is interposed between adjacent unit cells, and the unit cells are constrained in the arrangement direction by using the uneven shape of the spacer. The assembled battery is also configured to ensure a passage of a cooling medium (typically air) between the single cells. Patent Document 4 relates to a battery cover for reducing noise in an engine room of an automobile.

JP 2006-048996 A JP 2001-196103 A JP 2004-327142 A Japanese Utility Model Publication No. 60-12263

  By the way, when the assembled battery as described above is used (at the time of charging and / or discharging), the unit cells constituting the assembled battery may emit noise (noise). For example, when the assembled battery is used in a mode connected to a switching circuit (that is, in a mode of charging / discharging via the switching circuit, for example, as a component of a power supply system including the assembled battery and the switching circuit), the switching is performed. Depending on the operating frequency of the circuit (for example, about 10 kHz), noise may be generated from the cells constituting the assembled battery. The occurrence of such noise is considered to be mainly due to the expansion / contraction of the cell in response to the ripple of the charge / discharge current flowing through the switching circuit, which causes the surrounding air to vibrate. When noise generated from a single cell is observed remarkably outside the assembled battery (that is, noise from the single cell leaks significantly outside the assembled battery), the assembled battery is regarded as a problem that causes noise. There is.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an assembled battery in which a plurality of single cells are arranged and capable of reducing noise leaking outside the assembled battery.

  The present inventor has found that the above problem can be solved by interposing a spacer having a predetermined structure between the unit cells constituting the assembled battery, and has completed the present invention.

According to the present invention, an assembled battery configured by arranging a plurality of chargeable / dischargeable cells in a predetermined direction is provided. In the assembled battery, a spacer is interposed between the adjacent unit cells. The spacer includes a contact portion that contacts at least one unit cell among the adjacent unit cells, and a non-contact portion that spreads in a planar shape without contacting any unit cell. The non-contact portion is provided with a plurality of through holes. On both sides of the non-contact portion, a gap communicating with the through hole is formed between the unit cells.
According to the assembled battery having such a configuration, a non-contact portion (hereinafter sometimes referred to as a “perforated plate portion”) that spreads in a planar shape (plate shape) and has a plurality of through holes, and a gap (described above) From the unit cell facing the perforated plate portion, utilizing the “perforated plate sound absorbing structure” configured to communicate with the through-hole, and is typically filled with air to form an air layer. Noise can be absorbed (reduced). As a result, noise leaking to the outside of the assembled battery can be reduced.

  In the present specification, the “single cell” is a term indicating individual power storage elements constituting the assembled battery, and includes batteries and capacitors of various compositions and configurations unless specifically limited. The “secondary battery” refers to a battery that can be repeatedly charged, and includes so-called storage batteries such as lithium ion batteries and nickel metal hydride batteries. The storage element constituting the lithium ion battery is a typical example included in the “unit cell” referred to herein, and a lithium ion battery module including a plurality of such unit cells is the “assembled battery” disclosed herein. This is a typical example.

  It is preferable that the gap formed on at least one side of the non-contact portion constitutes a refrigerant passage that is open to the outside and can circulate the refrigerant. According to such a configuration, the heat generated from the unit cell can be dissipated into the refrigerant passage and quickly discharged to the outside of the assembled battery through the refrigerant (typically air is preferable) flowing through the passage. Therefore, the noise of the assembled battery can be reduced and the heat dissipation of the assembled battery can be increased.

  The non-contact portion and the size of the gap formed on at least one side thereof are set so as to form a perforated plate sound absorbing structure having a natural frequency corresponding to an operating frequency of a switching circuit connected to the assembled battery. Preferably it is. According to such a configuration, noise that may be generated from a single cell when charging / discharging through the switching circuit (for example, noise generated due to ripple of charging / discharging current) is particularly effectively absorbed, and the noise of the assembled battery is reduced. It can be suppressed to a higher degree.

  It is preferable that the unit cells have a flat box shape and are arranged so that the wide surfaces of the adjacent unit cells face each other. In the assembled battery having such a configuration, the area of the perforated plate portion is secured wider as necessary, and thereby noise from the unit cell facing the perforated plate portion is more highly absorbed (reduced). Can do. can do. Therefore, according to the assembled battery having the above-described configuration, the application effect of the technique disclosed herein can be better exhibited.

Any of the assembled batteries disclosed herein is suitable as an assembled battery mounted on a vehicle (for example, a power source for a motor (electric motor) mounted on a vehicle such as an automobile). Therefore, according to the present invention, a vehicle including any of the assembled batteries disclosed herein is provided.
As another aspect, the present invention provides a power supply system including any of the assembled batteries disclosed herein and a switching circuit electrically connected to the assembled batteries. As yet another aspect, a vehicle equipped with the power supply system is provided.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings, but the present invention is not intended to be limited to these specific embodiments. Moreover, in the following drawings, the same code | symbol is attached | subjected to the member and site | part which show | plays the same effect | action, and the overlapping description may be abbreviate | omitted.
Note that matters other than matters specifically mentioned in the present specification and necessary for carrying out the present invention (for example, the configuration and manufacturing method of the positive electrode, the negative electrode, and the separator, the method of restraining the unit cell, the assembled battery to the vehicle The mounting method) can be grasped as a design matter of those skilled in the art based on the prior art in the field. The present invention can be carried out based on the contents disclosed in this specification and common technical knowledge in the field.

First, a schematic configuration of the assembled battery 10 of the present embodiment will be described with reference to FIG. The assembled battery 10 is configured by arranging a plurality of chargeable / dischargeable cells 20 in a predetermined direction. In the example shown in the figure, four unit cells 20 having the same shape are arranged in one direction.
As shown in FIG. 2, each unit cell 20 includes an electrode body 80 including a positive electrode and a negative electrode, and a container 50 that houses the electrode body 80 and an electrolyte (not shown). The electrode body 80 of the present embodiment is composed of predetermined battery constituent materials (active materials for each of the positive and negative electrodes, current collectors for each of the positive and negative electrodes, a separator, and the like), as in the case of the unit cell included in a typical assembled battery. Has been. Here, a flat wound electrode body 80 described later is used as the electrode body 80.

The container 50 of the present embodiment has a shape (a flat box shape in the illustrated example) that can accommodate such a flat wound electrode body 80 inside. The material of the container 50 can be the same as that of a typical unit cell, and is not particularly limited. However, from the viewpoint of reducing the weight of the assembled battery itself, for example, a thin metal or synthetic resin container is preferable. Can be used.
On the upper surface of the container 50, a positive electrode terminal 60 that is electrically connected to the positive electrode of the wound electrode body 80 and a negative electrode terminal 62 that is electrically connected to the negative electrode of the wound electrode body 80 are provided. And between the adjacent unit cells 20, the positive electrode terminal 60 of one unit cell 20 and the negative electrode terminal 62 of the other unit cell 20 are electrically connected by a connector 64. In this way, by connecting the unit cells 20 in series electrically, the assembled battery 10 having a desired voltage is constructed (manufactured).

  The unit cells 20 of this embodiment are constrained in a state where they are arranged in a predetermined direction and a load is applied in the arrangement direction. Specifically, the plurality of single cells 20 are arranged one by one so that the positive terminals 60 and the negative terminals 62 of each single cell 20 are alternately arranged as viewed from the arrangement direction. The side walls 52 (the wide surface of the container 50, that is, the surface corresponding to the flat surface of a wound electrode body 80 described later housed in the container 50) are arranged in the facing direction.

  In the unit cells 20 arranged as described above, a spacer 40 is sandwiched (interposed) at least at one location between the adjacent unit cells 20. In the example shown in FIG. 1, spacers 40 are arranged between adjacent unit cells 20, and spacers 40 are also arranged outside the unit cells 20 located on the outermost side (both ends) in the unit cell arrangement direction. Yes.

A constraining member that constrains them together is disposed around the plurality of cells 20 and the spacers 40 that are alternately arranged in this manner. That is, a pair of restraining plates 70A and 70B are arranged on the outer side of the spacer 40 arranged on both outsides in the unit cell arrangement direction. Further, a fastening beam member 72 is attached so as to bridge the pair of restraining plates 70A and 70B. Then, by tightening and fixing the end of the beam member 72 to the restraining plates 70A and 70B with screws 74, the unit cell 20 (and the spacer 40) is subjected to a predetermined load (for example, the surface that the container side wall 52 receives). The pressure can be constrained so that a pressure of about 2 × 10 ^{6 to} 5 × 10 ⁶ Pa is applied. A restraining load (surface pressure) in the tightening direction (that is, the arrangement direction) is applied to the container side wall 52 of each unit cell 20 at a level corresponding to the tightening degree of the beam material 72.

  Here, the spacer 40 of the present embodiment is in contact with at least one of the adjacent unit cells 20 (typically, at least at the container side wall 52) and any unit cell 20. And a non-contact portion 44 that spreads in a plane shape (plate shape). The planar shape of the spacer 40 (as viewed from the left side in FIG. 2) is almost the same rectangular shape as the container side wall 52, and the outer peripheral portion of the rectangle is the contact portion 42, and the central portion surrounded by the contact portion is non-contact. The portion 44 is configured.

  More specifically, on one surface of the spacer 40 (the left surface in FIG. 2), the lateral direction of the unit cell 20 is parallel to the upper and lower sides at a position slightly away from the upper and lower sides in the planar shape of the spacer 40. Two linear convex portions extending in the direction of the winding axis of the wound electrode body 80 are formed. In addition, an annular convex portion is formed on the other surface of the spacer 40 (the right surface in FIG. 2) along the outer periphery of the planar shape of the spacer 40. Of the contact portion 42 of the spacer 40, a portion where there is no protrusion on one surface and a protrusion is formed only on the other surface is in contact with the unit cell 20 on the other surface side (right side). The flange 422 is separated from the unit cell 20 on one surface side (left side). In addition, a portion where the convex portion formed on one surface and the convex portion formed on the other surface overlap as viewed from the plane direction is close to the unit cells 20 on both sides in the assembled battery 10 constrained as described above. The pressing portion 424 applies a pressing force to the container side surface 52 of the unit cells 20.

  The non-contact part 44 of the spacer 40 is provided with a plurality of through holes 46. The opening shape of the through-hole 46 may be a rounded shape (a shape such as a circle, an ellipse, or an oval), or a square shape (for example, a square shape such as a square, a rectangle, or a rhombus, preferably a regular shape). It may be a regular polygonal shape such as a triangle, a square, or a regular hexagon. Alternatively, it may be a slit-shaped through hole. A through hole 46 having a circular or hexagonal or more polygonal opening shape as shown in FIG. 5 is preferable. The shape and size of each through hole may be the same or different. It is preferable that through holes having the same shape and size are provided in at least a predetermined region (for example, a range of 50% or more including the central portion of the area of the non-contact portion 44). In the present embodiment, circular through holes 46 having the same shape and the same size are arranged at regular intervals (pitch) vertically and horizontally over substantially the entire area of the non-contact portion 44.

As described above, the non-contact portion (perforated plate portion) 44 is formed by the contact portion 42 having the convex portion on one surface side and the convex portion on the other surface side. Are spaced apart from each other by a gap communicating with the through hole 46.
That is, on one surface side (the left side in FIG. 2) of the non-contact portion 44, a belt-like shape having upper and lower ends partitioned by the pressing portion 424 between the non-contact portion 44 and the side surface 52 of the unit cell 20 on the left side of the non-contact portion 44. An air gap 49 is formed. Both ends of the air gap 49 in the lateral direction (paper surface direction in FIG. 2) are open to the outside, and heat from the unit cell 20 is efficiently dissipated by circulating a cooling medium (typically air) here. Can be made.
Further, on the other surface side (the right side in FIG. 2) of the non-contact portion 44, a rectangular plate-like (layered) gap 47 is formed between the side surface 52 of the unit cell 20 on the right side of the non-contact portion 44. ing. The outer periphery of the gap 47 is partitioned by the convex portion toward the other surface described above, so that the gap 47 is a space closed from the outside except for the through hole 46. Preferably, both the through hole 46 and the gaps 47 and 49 are filled with outside air (typically air).

  According to the assembled battery 10 having such a configuration, noise generated from the unit cells 20 constituting the assembled battery 10 can be absorbed (sound absorption) as follows. That is, the noise generated from the unit cell 20 arranged on the left side of the spacer 40 in FIG. 2 is transmitted from the side surface 52 of the unit cell 20 to the gap 49, and is separated from the side surface 52 across the gap 49. It passes through the through hole 46 of the contact portion 44 and enters a gap (typically an air layer) 47 provided on the back surface thereof. At this time, the noise from the left unit cell 20 is absorbed by the perforated plate sound absorbing structure formed by the through hole 46 and the gap 47. Thereby, the noise which leaks outside the assembled battery 10 can be reduced. In particular, in the embodiment in which the gap 49 is used as a refrigerant passage opened to the outside as in the present embodiment, noise from the unit cell 20 tends to leak from the side surface 52 through the gap 49 to the outside of the assembled battery 10. By providing the sound absorbing structure, noise observed outside the assembled battery 10 can be effectively reduced.

When the frequency of noise generated from the unit cell 20 can be predicted (in other words, mainly when reducing noise at a specific frequency), a perforated plate sound absorbing structure having a natural frequency corresponding to the frequency is formed. By setting the sizes of the non-contact portion 44 and the gap 47 so that the noise can be absorbed particularly efficiently. In other words, the case where the opening shape of the through hole 46 is a circular shape will be described with reference to FIG. 5 as an example, and the natural frequency f of the perforated plate sound absorbing structure (the space formed by the through hole 46 and the gap 47). ₀ is generally represented by the following formula (1).

Here, d in the above formula represents the diameter of the through hole 46, D represents the pitch of the through hole 46, t represents the thickness of the non-contact portion 44, and L represents the back surface of the non-contact portion 44. The thickness of the space | gap (air layer) 47 is each represented (refer FIG. 5). Further, P in the equation is an aperture ratio in the non-contact portion 44, and in the example shown here, is obtained by the following equation: P = (πd ² / 4D ² ); Note that c in the equation represents the speed of sound.

Therefore, the shape of the non-contact portion 44 (opening ratio (diameter and pitch of the through-hole 46 and the plate thickness of the non-contact portion 44)) and the air gap 47 are set so that the natural frequency f ₀ matches the predicted frequency f of noise. It is good to set the thickness. When the frequency f of the noise (input noise) from the unit cell 40 matches the natural frequency f ₀ , the air in the through hole 46 and the gap 47 is vibrated vigorously and converted to heat. Reduced (absorbed).

The assembled battery 10 having the above-described configuration is, for example, a power system including the assembled battery 10 and a switching circuit (not shown) in a form electrically connected to a known switching circuit (for example, a power system mounted on a vehicle such as an automobile). As a component. In such a usage mode, when noise caused by the ripple of the charge / discharge current flowing through the switching circuit (for example, caused by expansion / contraction of the unit cell in response to the ripple) is reduced, the operation of the switching circuit is performed. By setting the shape of the spacer 40 (the size of each part of the non-contact part 44 and the gap 47) so that a perforated plate sound absorbing structure with a natural frequency f ₀ matched to the frequency is formed, an excellent noise reduction effect can be obtained. Can be realized. As a specific example of the shape setting, when the operating frequency of the switching circuit is 10 kHz, d in the above formula (1) is 1.6 mm, D is 5 mm, t is 1 mm, and L is 1 mm. By setting the shapes (sizes) of the non-contact part 44 and the gap 47 so that a perforated plate sound absorbing structure with a natural frequency f ₀ of 10 kHz can be formed, noise of the frequency can be efficiently generated. Can absorb sound.
For the perforated plate sound absorption structure other than those exemplified here (for example, the opening shape and arrangement of the through holes are different), the natural frequency can be obtained by a known technique, and the configuration of each assembled battery (each part) Size etc.) can be designed.

Next, the configuration of the unit cell 20 that can be used in the present embodiment, each material constituting the unit cell 20 and the like will be described in detail. The battery pack 10 according to the present embodiment may be a battery pack 10 in which a rechargeable secondary battery is a single battery 20 and a plurality of such single batteries 20 are connected in series. The configuration is not particularly limited. A nickel-metal hydride battery, an electric double layer capacitor, etc. are mentioned as a structure of the cell suitable for implementation of this invention. In particular, the configuration of the unit cell suitable for the implementation of the present invention is a lithium ion battery. Since the lithium ion battery is a secondary battery that can achieve high output at a high energy density, a high-performance assembled battery, in particular, an assembled battery for a vehicle (battery module) can be constructed.
As described above, the unit cell 20 includes the electrode body 80 including the positive electrode and the negative electrode, and the container 50 that stores the electrode body 80 and the electrolyte (see FIG. 2).

  First, the configuration of the container 50 will be described. The material of the container 50 is not particularly limited as long as it is the same as that used in the conventional unit cell, but usually a relatively light material is preferably used. For example, a metal container whose surface is preferably coated with an insulating resin coating, a polyolefin resin such as polypropylene, and other synthetic resin containers are suitable. Alternatively, a resin film container conventionally used as a battery exterior body, for example, an outer surface (protection) layer composed of a high melting point resin (for example, polyethylene terephthalate, polytetrafluoroethylene, polyamide-based resin) and a metal foil (for example, A barrier layer composed of aluminum and steel (that is, a layer capable of blocking gas and moisture) and a heat-fusible resin (a resin having a relatively low melting point, for example, ethylene vinyl acetate, polyolefins such as polyethylene and polypropylene) It may be a laminate film container having a three-layer structure with an adhesive layer made of a resin. In the present embodiment, a polypropylene container 50 is used.

  Next, the configuration of the wound electrode body 80 accommodated in the container 50 will be described in detail with reference to FIG. The wound electrode body 80 according to the present embodiment has a sheet-like positive electrode 82 (hereinafter referred to as “positive electrode sheet 82”) and a sheet-like negative electrode 84 (hereinafter referred to as “negative electrode sheet 84”), similarly to a wound electrode body of a normal lithium ion battery. Is laminated with two sheet-like separators 86 (hereinafter referred to as “separator sheet 86”), and the positive electrode sheet 82 and the negative electrode sheet 84 are wound while being slightly shifted, and then the obtained wound body is obtained. This is a flat wound electrode body 80 produced by crushing and ablating from the lateral direction.

  As shown in FIG. 6, in the lateral direction (winding axis direction) of the wound electrode body 80 with respect to the winding direction, the positive electrode sheet 82 and the negative electrode sheet 84 are wound as described above while being slightly shifted as described above. Part of the end is outside the wound core portion 81 (that is, the portion where the positive electrode active material layer forming portion of the positive electrode sheet 82, the negative electrode active material layer forming portion of the negative electrode sheet 84 and the separator sheet 86 are closely wound). It sticks out toward you. A positive electrode lead terminal 82B and a negative electrode lead terminal 84B are attached to the protruding portion (that is, the non-formed portion of the positive electrode active material layer) 82A and the protruding portion of the negative electrode side (that is, the non-formed portion of the negative electrode active material layer) 84A, respectively. ing. These lead terminals 82B and 84B are electrically connected to the positive terminal 60 and the negative terminal 62, respectively.

In addition, the material and member itself which comprise this winding electrode body 80 may be the same as that of the electrode body of the conventional lithium ion battery, and there is no restriction | limiting in particular. For example, the positive electrode sheet 82 can be formed by applying a positive electrode active material layer for a lithium ion battery on a long positive electrode current collector. For the positive electrode current collector, an aluminum foil (this embodiment) or other metal foil suitable for the positive electrode is preferably used. As the positive electrode active material, one or more of materials conventionally used in lithium ion batteries can be used without any particular limitation. Preferable examples include LiMn ₂ O ₄ , LiCoO ₂ , LiNiO _{2 and the} like. For example, an aluminum foil having a length of 2 m to 4 m (for example, 2.7 m), a width of 8 cm to 12 cm (for example, 10 cm), and a thickness of about 5 μm to 20 μm (for example, 15 μm) is used as a current collector. A positive electrode active material layer for lithium ion batteries mainly composed of lithium nickelate is formed by a conventional method (for example, lithium nickelate 88% by mass, acetylene black 10% by mass, polytetrafluoroethylene 1% by mass, carboxymethylcellulose 1% by mass). Thus, a suitable positive electrode sheet 82 is obtained.

  On the other hand, the negative electrode sheet 84 may be formed by applying a negative electrode active material layer for a lithium ion battery on a long negative electrode current collector. For the negative electrode current collector, a copper foil (this embodiment) or other metal foil suitable for the negative electrode is preferably used. As the negative electrode active material, one or more of materials conventionally used in lithium ion batteries can be used without any particular limitation. Preferable examples include carbon-based materials such as graphite carbon and amorphous carbon, lithium-containing transition metal oxides and transition metal nitrides. For example, a copper foil having a length of 2 m to 4 m (for example, 2.9 m), a width of 8 cm to 12 cm (for example, 10 cm), and a thickness of about 5 μm to 20 μm (for example, 10 μm) is used. A suitable negative electrode sheet 84 is obtained by forming a negative electrode active material layer (for example, 98% by mass of graphite, 1% by mass of styrene butadiene rubber, and 1% by mass of carboxymethyl cellulose) for lithium ion batteries.

Moreover, as a suitable separator sheet 86 used between the positive / negative electrode sheets 82 and 84, the thing comprised by the porous polyolefin-type resin is mentioned. For example, a porous separator sheet made of a synthetic resin (for example, made of polyolefin such as polyethylene) having a length of 2 m to 4 m (for example, 3.1 m), a width of 8 cm to 12 cm (for example, 11 cm), and a thickness of about 5 μm to 30 μm (for example, 25 μm). It can be preferably used. When a solid electrolyte or a gel electrolyte is used as the electrolyte, a separator may not be necessary (that is, in this case, the electrolyte itself can function as a separator).
In addition, the electrode body accommodated in the container of a cell is not limited to the said winding type. For example, a laminate type electrode body in which positive electrode sheets and negative electrode sheets are alternately laminated together with a separator (or a solid or gel electrolyte that can also function as a separator) may be used.

Then, the structure of the electrolyte accommodated in the container 50 with the said winding electrode body 80 is demonstrated. The electrolyte of this embodiment is a lithium salt such as LiPF ₆ . In the present embodiment, an appropriate amount (for example, concentration 1M) of a lithium salt such as LiPF ₆ is dissolved in a nonaqueous electrolytic solution such as a mixed solvent of diethyl carbonate and ethylene carbonate (for example, a mass ratio of 1: 1) to prepare an electrolytic solution. It is used as The unit cell 20 of this embodiment is constructed by housing the wound electrode body 80 in the container 50 and injecting and sealing the electrolyte. And the assembled battery 10 of this embodiment is constructed | assembled by arranging the cell 20 in a predetermined direction and restraining the cell 20 and the spacer 40 in the arrangement direction.

In the above-described embodiment, noise generated from the single cells 20 is reduced (sound absorption) using the spacers 40 arranged between the adjacent single cells 20, and the refrigerant passage is configured by the spacers 40. Therefore, the effect of reducing the noise of the assembled battery 10 and the effect of improving heat dissipation can be realized by the spacer 40 while suppressing the increase in the number of parts and the size of the assembled battery 10.
In addition, as a constituent material of the spacer 40, various synthetic resins can be preferably employed from the viewpoint of workability and the like. It is preferable to use a light and hard synthetic resin. For example, a spacer 40 made of polypropylene can be preferably used. In addition, from the viewpoint of heat dissipation and the like, a metal spacer 40 with good thermal conductivity can be preferably used.

  In the above description, the gap 47 provided on the back surface of the through hole 46 is closed at a portion other than the through hole 46. However, the gap 47 is open to the outside like the opposite gap 49. Also good. Thereby, since the space | gap 47 can be functioned not only as a space for sound absorption (air layer) but as a refrigerant path, the heat dissipated from the cell 20 can be dissipated more efficiently. In the above description, the noise generated from the unit cell 20 located on the left side of the non-contact part 44 is described in detail with respect to the noise absorption by the non-contact part 44 and the gap 47 on the back surface (right side). Noise generated from the unit cell 20 located on the right side of the contact portion 44 is generated by the non-contact portion 44 and the gap 49 on the back surface (left side) (that is, the non-contact portion 44 and the void 49 formed on the back surface thereof. Sound absorption is possible (using a board sound absorbing structure). From the viewpoint of enhancing sound absorption characteristics (especially efficiently absorbing noise of a specific frequency), a perforated plate sound absorbing structure is formed by the closed hole in the through hole 46 and the part other than the through hole 46. It is more advantageous to do so.

  The assembled battery 10 according to the present embodiment can be suitably used as a power source for a motor (electric motor) mounted on a vehicle such as an automobile. Therefore, according to the present invention, as schematically shown in FIG. 7, a vehicle (typically, an electric motor such as an automobile, particularly a hybrid automobile, an electric automobile, a fuel cell automobile, etc.) provided with the assembled battery 10 as a power source. Automobile) 1 can be provided.

As described above, the present invention has been described with reference to the preferred embodiments. However, such description is not a limitation, and various modifications can be made.
For example, in the above embodiment, the outer peripheral portion of the spacer 40 viewed from the plane direction is the contact portion 42, and the entire rectangular region inside (the center portion) is configured as the non-contact portion 44. The arrangement is not limited to this. For example, as shown in FIG. 3, in addition to the contact portion 42 provided on the outer peripheral portion of the spacer 40 (or in place of the contact portion of the outer peripheral portion), a dot-like (columnar) or linear shape is formed in the central portion of the spacer 40. A (ridge-shaped) convex portion 426 may be provided. The convex portion 426 may be configured to contact only one of the unit cells 20 and functions as a pressing unit that contacts (closely contacts) the side walls 52 of the unit cells 20 on both sides as shown in FIG. It may be configured as follows. The gap 47 and / or the gap 49 may be divided (partitioned) into a plurality of portions by the linear protrusions 426.
Further, in the above-described embodiment, the contact portions 42 are protruded on both sides of the spacer 40 in the thickness direction (projected shape) to form the gap 47 and the gap 49 on both sides of the non-contact portion 44. Is not limited to this, and for example, as shown in FIG. 4, a convex portion 522 is formed on the side surface 52 of the unit cell 20 located on the right side of the non-contact portion 44. A gap 47 may be formed between the non-contact part 44 and the single battery 20 (side surface 52 of the part other than the convex part 522). The thickness of the gap 47 can be adjusted by the height of the convex portion 522.

  In addition, when the assembled battery disclosed herein is mounted on a vehicle such as an automobile, more cells can be connected in series, and an exterior for protecting the main part of the assembled battery (unit cell group, etc.) A cover, a part for fixing the assembled battery to a predetermined part of the vehicle, a part for connecting a plurality of assembled batteries (battery modules) to each other can be provided. It does not affect the technical scope. In addition, the type of the unit cell is not limited to the above-described lithium ion battery, but various batteries having different electrode body constituent materials and electrolytes, for example, a lithium secondary battery having a negative electrode made of lithium metal or a lithium alloy, a nickel hydrogen battery, and a nickel cadmium battery. Alternatively, an electric double layer capacitor may be used.

  ADVANTAGE OF THE INVENTION According to this invention, even if noise arises from the single battery which comprises an assembled battery, the assembled battery which can reduce the noise which leaks to the exterior of this assembled battery can be provided.

It is a perspective view showing typically an assembled battery concerning one embodiment. It is sectional drawing which shows typically the cross section which cut | disconnected a part of assembled battery which concerns on one Embodiment along the sequence direction. It is sectional drawing which shows typically the cross section which cut | disconnected a part of assembled battery which concerns on other embodiment along the sequence direction. Furthermore, it is sectional drawing which shows typically the cross section which cut | disconnected a part of assembled battery which concerns on other embodiment along the sequence direction. It is explanatory drawing which shows typically the structural example of a perforated board sound absorption structure. It is a front view which shows typically an example of a wound electrode body. It is a side view which shows typically the vehicle (automobile) provided with the assembled battery of this invention.

Explanation of symbols

1 Vehicle (Automobile)
10 assembled battery 20 single cell 40 spacer 42 contact part 44 non-contact part (perforated plate part)
46 Through-hole 47 Air gap (air layer)
49 Air gap (refrigerant passage)
50 Container 52 Container side wall (wide surface)
60 positive electrode terminal 62 negative electrode terminal 64 connector 80 electrode body

Claims (5)

An assembled battery configured by arranging a plurality of chargeable / dischargeable cells in a predetermined direction,
A spacer is interposed between the adjacent unit cells,
The spacer includes a contact portion that contacts at least one unit cell among the adjacent unit cells, and a non-contact portion that spreads in a planar shape without contacting any unit cell,
The non-contact portion is provided with a plurality of through holes,
An assembled battery in which a gap communicating with the through hole is formed on both sides of the non-contact portion between the single battery.   The assembled battery according to claim 1, wherein the gap formed on at least one side of the non-contact portion constitutes a refrigerant passage that is open to the outside and through which a refrigerant can flow.   The non-contact portion and the size of the gap formed on at least one side thereof are set so as to form a perforated plate sound absorbing structure having a natural frequency corresponding to an operating frequency of a switching circuit connected to the assembled battery. The assembled battery according to claim 1 or 2.   The assembled battery according to any one of claims 1 to 3, wherein the unit cells are flat box-shaped and arranged so that the wide surfaces of the adjacent unit cells face each other.   A vehicle comprising the assembled battery according to any one of claims 1 to 4.

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