JP4576823B2 - Assembled battery - Google Patents

Description

  The present invention relates to an assembled battery having a plurality of unit cells.

  In recent years, in response to growing environmental awareness, there is a movement to shift the power source of automobiles from an engine using fossil fuel to a motor using electric energy. Therefore, the technology of the battery that serves as the power source of the motor is also rapidly developing.

In the conventional assembled battery, the cells connected in series and / or in parallel are stacked at a predetermined interval, pressed through the cells located in the outermost layer, and fixed by the exterior member, An assembled battery having improved cycle characteristics and rate characteristics is obtained by improving the heat dissipation characteristics of the single cell (see, for example, Patent Document 1).
JP 2000-195480 A

  However, the assembled battery needs to incorporate a large number of single cells, and handling thereof requires a great deal of labor. For example, since it is difficult to position and stack single cells, there is a problem that work man-hours increase and productivity decreases. In addition, it is difficult to improve the assembly accuracy, and there is a risk of poor insulation and insufficient clearance.

  The present invention has been made to solve the problems associated with the above-described prior art, and an object thereof is to provide an assembled battery having good productivity and assembly accuracy.

To achieve the above object, the present invention provides:
An assembled battery in which a plurality of unit cells stacked are incorporated,
Having a plurality of storage cases having flexibility and electrical insulation for storing the unit cells;
The said storage case, the positioning means about the stacking direction is formed,
The positioning means is a battery pack , wherein the positioning means is a through-hole, or a protrusion and a recess that fit into each other .

  According to the present invention configured as described above, the unit cell is stored in the storage case that can be easily positioned and stacked, so that it is easy to handle and excellent in productivity. Further, the storage case can easily ensure the assembly accuracy, and the occurrence of poor insulation and insufficient clearance is suppressed. Therefore, it is possible to provide an assembled battery having good productivity and assembly accuracy.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view for explaining an assembled battery according to an embodiment of the present invention.

  The assembled battery 10 according to the embodiment of the present invention includes a stacked portion 20 of a storage case 30 in which a single battery is stored, a support plate 80 and a pressing plate 85 disposed on both sides of the stacked portion 20, and a stacked portion 20 ( And holding means 90 for pressurizing and fixing the storage case 30). Reference numeral 95 denotes a nut that the holding means 90 has.

  2 is a perspective view for explaining a storage case according to the embodiment of the present invention, FIG. 3 is a sectional view taken along line III-III in FIG. 2, and FIG. 4 is a storage according to the embodiment of the present invention. FIG. 5 is a front view of the case, and FIG. 5 is a rear view of the storage case according to the embodiment of the present invention.

  The storage case 30 has a substantially flat bag shape and has an upper surface 40 and a lower surface 50. The material of the storage case 30 is not particularly limited as long as it has electrical insulation properties and flexibility that does not break due to pressurization by the holding means 90.

  The storage case 30 stores a pair of single cells 60 and 70, and one electrode tabs 67 and 77 are connected in advance to each other. The electrode tabs 65 and 67 and the electrode tabs 75 and 77 having different polarities of the unit cell 60 and the unit cell 70 extend from opposing end surfaces. The end portion 36 is partially bonded after the cells 60 and 70 are accommodated, and is closed by forming the bonding portion 38.

  As described above, since the single cells 60 and 70 are stored in the storage case 30 that can be easily positioned and stacked, the single cells 60 and 70 are easy to handle and excellent in productivity. Further, the storage case 30 can easily ensure the assembly accuracy, and the occurrence of poor insulation and insufficient clearance is suppressed. Therefore, it is possible to provide an assembled battery having good productivity and assembly accuracy. Furthermore, since the single cells are housed in pairs, handling and insulation are improved.

  More specifically, the storage case 30 includes a stopper means 31, a cut portion 44, a through hole 34, openings 46 and 56, an upper surface extension portion 42, and a lower surface extension portion 52.

  The stopper means 31 includes a joint portion formed by partially joining the upper surface 40 and the lower surface 50. The stopper means 31 restricts the movement when the cells 60 and 70 are accommodated via the end portion 36 before being blocked, and positions the cells 60 and 70 at predetermined positions. For example, welding, stapling, and adhesion can be applied to the joint portion.

  The notches 44 and 54 are slits for drawing out the electrode tabs 65 and 75 of the single cells 60 and 70, and are formed on the upper surface 40 and the lower surface 50. Therefore, it is easy to pull out the electrode tabs 65 and 75 of the single cells 60 and 70 to the outside of the storage case 30.

  The electrode tab 75 drawn out from the notch 44 on the upper surface 40 is connected in series with the electrode tab drawn out from the notch on the lower surface of the adjacent upper storage case. The electrode tab 65 drawn out from the cut portion 54 on the lower surface 50 is connected in series with the electrode tab drawn out from the cut portion on the upper surface of the adjacent lower storage case.

  Moreover, a clip metal fitting is used as a connection means of an electrode tab. The clip metal fitting is preferable because it is easy to handle and inexpensive, but other connection means can be applied as appropriate.

  The through holes 34 are positioning means in the stacking direction of the storage case 30 and are formed at the four corners of the storage case 30. The through hole 34 inserts a locate pin (described later), thereby facilitating the stacking operation of the plurality of storage cases 30 and improving the assembly accuracy.

  The positioning means is not limited to using the through-hole 34. For example, the storage case 30 is stacked by repeatedly providing the protrusions and the recesses on the upper surface 40 and the lower surface 50 and fitting the protrusions into the recesses. By doing so, positioning is also possible.

  The openings 46 and 56 are heat radiating holes for releasing heat generated from the single cells 60 and 70. The shape, number and arrangement of the openings 46 and 56 are preferably set as appropriate according to the thermal characteristics of the storage case 30 (unit cells 60 and 70).

  The upper surface extension portion 42 is a protection means for preventing the clip metal fitting from dropping off and insulating the electrode tab connected by the clip metal fitting (between adjacent storage cases). The upper surface extension portion 42 has an apron shape and extends from an end portion of the upper surface 40 of the storage case where the electrode tab 75 is disposed. The upper surface extended portion 42 is bent downward, covers the clip metal fitting and the electrode tab, and is joined to the adjacent storage case.

  The lower surface extension 52 is a short-circuit prevention means for insulating the electrode tabs 65 and 75 from each other. The lower surface extension portion 52 has an apron shape and extends from an end portion of the lower surface 50 of the storage case where the electrode tab 65 is disposed. The lower surface extension 52 is bent upward and is disposed between the electrode tabs 65 and 75. The lower surface extension portion 52 is bent before the upper surface extension portion 42 is bent.

  FIG. 6 is a perspective view for explaining the single battery shown in FIG. Since the single battery 60 and the single battery 70 have the same structure, the single battery 60 will be described as an example.

  The unit cell 60 includes an outer case 62 made of a laminate film whose peripheral portions are joined by heat welding, and electrode tabs 65 and 67 drawn from the outer case 62. For heat welding, for example, ultrasonic welding can be applied.

  The material of the laminate film is not particularly limited, and examples thereof include a polymer-metal composite material formed by integrating an exterior protective layer made of a polymer film, a metal film layer, and a heat welding layer made of a polymer film. .

  The exterior case 62 is rectangular and flat, and has a convex portion 64 for housing the power generation element and a heat welding portion 63 for sealing the inside. The power generation element includes, for example, a positive electrode plate, a positive electrode current collector, a separator, a negative electrode plate, a negative electrode current collector, and an electrolytic solution (electrolyte). The positive electrode current collector is a member for connecting the positive electrode plate and one end of the electrode tab 67 inside the outer case 62. The negative electrode current collector is a member for connecting the negative electrode plate and one end of the electrode tab 65 inside the outer case 62. The electrode tab 67 is made of aluminum foil, and the electrode tab 65 is made of copper foil.

  Since the single cells 60 and 70 are connected in series to the single cells in the adjacent storage case by the clip fitting, a stacked body connected in series in the stacking direction is formed. In addition, the electrode tab 65 of the unit cell 60 of the storage case 30 located in the lowermost layer and the electrode tab 75 of the unit cell 70 of the storage case 30 located in the uppermost layer are connected to the power terminal (not-used) using an appropriate connection conductor. Connected). Therefore, it is possible to supply large power to a power source (for example, a motor) connected to the power terminal.

  FIG. 7 is a perspective view for explaining the support plate shown in FIG. 1.

  The support plate 80 is used for placing the storage case 30 and has holes 82 at four corners. The hole 82 is aligned with the through hole 34 of the storage case 30, and one end of the locate pin 92 is fixed. Therefore, the locate pin 92 is aligned with the through hole 34. The other end of the locate pin 92 has a threaded portion 93.

  The support plate 80 has a heat sink function for absorbing heat generated from the single cells 60 and 70 and dissipating the heat to the outside. The constituent material of the support plate 80 is preferably copper, aluminum, magnesium or the like, and aluminum is particularly preferable in consideration of heat dissipation and weight reduction. Further, it is possible to improve the heat radiation efficiency by forming a plurality of vent holes penetrating and extending in the longitudinal direction in the support plate 80.

  FIG. 8 is a perspective view for explaining the pressing plate shown in FIG.

  The pressing plate 85 is placed on the uppermost storage case 30, and through holes 87 are formed at the four corners. The through hole 87 is aligned with the locate pin 92, and the other end of the locate pin 92 passes therethrough.

  Therefore, by fastening the nut 95 to the screw portion 93 that has passed through the through hole 87, the pressing plate 85 pressurizes the stacked portion 20 (storage case 30) of the storage case 30 placed on the support plate 80. And can be fixed. That is, the locating pin 92 and the nut 95 constitute the holding means 90.

  In general, the outer case of a flat unit cell has a weak force to hold down the internal electrodes, and the gas generated by repeated charge and discharge flows between the internal electrodes, shortening the life by causing cycle deterioration. Have a problem to do. Therefore, it is preferable that an appropriate surface pressure is applied to the stacked portion 20 by the holding means 90, the internal electrodes are pressed down, the inflow of gas is suppressed, and the shortening of the life due to cycle deterioration is prevented.

  The pressing plate 85 has a heat sink function for absorbing the heat generated from the single cells 60 and 70 and dissipating the heat to the outside. The constituent material of the pressing plate 85 is preferably copper, aluminum, magnesium or the like, and aluminum is particularly preferable in consideration of heat dissipation and weight reduction. Moreover, it is also possible to improve the heat radiation efficiency by forming a plurality of vent holes penetrating and extending in the longitudinal direction in the pressing plate 85.

  The holding means 90 uses a locate pin 92 used for positioning in the stacking direction of the storage case 30 to pressurize and fix the stacked portion 20 (storage case 30). However, it is possible to configure the holding means 90 to have a dedicated pin member standing on the support plate 80 and fasten the pin portion and the nut 95 together.

  Next, the manufacturing process of the assembled battery according to the embodiment of the present invention will be described.

  FIG. 9 is a cross-sectional view for explaining a cell storage process for the storage case, FIG. 10 is a cross-sectional view for explaining the cell positioning process in the storage case, following FIG. 9, and FIG. , FIG. 10 is a perspective view for explaining a storage case joining process, FIG. 12 is a cross-sectional view taken along line XII-XII in FIG. 11, and FIG. 13 is a view of FIG. 14 is a cross-sectional view for explaining the process, FIG. 14 is a perspective view for explaining the stacking process of the storage case subsequent to FIG. 13, and FIG. 15 is a process for connecting the electrode tab by the clip metal fitting following FIG. FIG. 16 is a perspective view for explaining a clip metal fitting and electrode tab protection process following FIG. 15, FIG. 17 is a cross-sectional view taken along line XVII-XVII in FIG. 16, and FIG. Continuing from Figure 16 It is a cross-sectional view for explaining a case of pressing and fixing step.

  First, a pair of single cells 60 and 70 in which one electrode tabs 67 and 77 are connected in advance to each other are stored via the end portion 36 in the storage case 30 with the end portion 36 open (see FIG. (See FIG. 9).

  When the cells 60 and 70 are inserted until they contact the stopper means 32 and positioned at a predetermined position, the electrode tab 65 is pulled out from the cut portion 54 of the lower surface 50, and the electrode tab 75 is cut into the upper surface 40. It is pulled out from the section 44 (see FIG. 10). Thereafter, the end portion 36 of the storage case 30 is joined and closed (see FIGS. 11 and 12).

  And the lower surface expansion part 52 of the storage case 30 is bend | folded upwards and it arrange | positions between the electrode tabs 65 and 75 (between the single cells 60 and 70), the electrode tabs 65 and 75 are insulated, and it short-circuits. Prevention is achieved (see FIG. 13).

  The completed storage case (assembly) 30 is placed on the support plate 80 (see FIG. 14). At this time, the positioning of the storage case 30 in the stacking direction is performed by passing the locate pin 92 erected on the support plate 80 through the through hole 34 of the storage case 30. Therefore, the stacking operation of the storage cases 30 is easy and the assembly accuracy is ensured.

  Next, the electrode tab 75 drawn out from the cut portion 44 of the upper surface 40 is connected in series with the electrode tab 65 drawn from the cut portion 54 of the lower surface 50 of the adjacent upper storage case (see FIG. 15). . Connection of the electrode tabs 65 and 75 is easy because the clip fitting 22 is used.

  The upper extended portion 42 of the storage case is bent downward so as to cover the clip metal fitting 22 and the electrode tab, and joined to the adjacent storage case (see FIGS. 16 and 17). Therefore, the clip metal fitting 22 is prevented from falling off, and the electrode tab connected by the clip metal fitting 21 (between adjacent storage cases) is reliably insulated.

  When a predetermined number of storage cases 30 are stacked, the pressing plate 85 is placed on the uppermost storage case 30 and a nut 95 is fastened to the threaded portion 93 at the other end of the locate pin 92 protruding from the through hole 87. (See FIG. 18). At this time, by applying an appropriate surface pressure to the stacked portion 20, the inflow of gas generated by repeating charging and discharging is suppressed, and shortening of the life due to cycle deterioration is prevented.

  As described above, in the assembled battery according to the embodiment, all the single cells are connected in series, and large power can be supplied. Moreover, since the unit cell is stored in a storage case that can be easily positioned and stacked, it is easy to handle and has excellent productivity. Further, the storage case can easily ensure the assembly accuracy, and the occurrence of poor insulation and insufficient clearance is suppressed. Therefore, it is possible to provide an assembled battery having good productivity and assembly accuracy.

  The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims.

  For example, as shown in FIG. 19, it is also possible to connect the storage cases 30 in parallel to form an assembled battery. In this case, since the cell stacks connected in series in the stacking direction are formed in parallel, for example, connecting conductors such as bus bars are appropriately arranged on the pressing plate and / or the support plate, and the stacks are connected in series. It is preferable to connect to.

  Further, as shown in FIG. 20, the storage case 30 is provided with an apron-like extension portion 48 for covering the electrode tab 75 drawn out from the cut portion 44, thereby further ensuring insulation management and prevention of short circuit. It is also preferable. Since the extension part 48 can be rolled up when the electrode tab 75 is connected by the clip metal fitting, the connection work is not hindered.

  The unit cells stored in the storage case are not limited to a pair, and a stacked body in which three or more cells are connected in series can also be applied. Furthermore, it is possible to use a single cell (see FIG. 21) in which electrode tabs having different polarities extend in parallel from the same end face.

  In addition, it is possible to further improve the heat radiation efficiency by arranging plates having a heat sink function at appropriate intervals between the stacked storage cases.

It is a perspective view for demonstrating the assembled battery which concerns on embodiment of this invention. It is a perspective view for demonstrating the storage case which concerns on embodiment of this invention. It is sectional drawing regarding line III-III of FIG. It is a front view of the storage case which concerns on embodiment of this invention. It is a rear view of the storage case which concerns on embodiment of this invention. It is a perspective view for demonstrating the cell shown by FIG. It is a perspective view for demonstrating the support plate shown by FIG. It is a perspective view for demonstrating the press plate shown by FIG. It is sectional drawing for demonstrating the manufacturing process of the assembled battery which concerns on embodiment of this invention, and has shown the accommodation process of the cell with respect to a storage case. FIG. 10 is a cross-sectional view for explaining a unit cell positioning step in the storage case following FIG. 9. It is a perspective view for demonstrating the joining process of a storage case following FIG. It is sectional drawing regarding the line XII-XII of FIG. FIG. 12 is a cross-sectional view for explaining a bending process of the extended portion of the storage case following FIG. 11. It is a perspective view for demonstrating the lamination | stacking process of a storage case following FIG. It is sectional drawing for demonstrating the connection process of the electrode tab by a clip metal fitting following FIG. FIG. 16 is a perspective view for explaining a clip metal fitting and electrode tab protection process following FIG. 15. It is sectional drawing regarding line XVII-XVII of FIG. It is sectional drawing for demonstrating the press fixing process of a storage case following FIG. It is a perspective view for demonstrating the storage case which concerns on another embodiment of this invention. It is a perspective view for demonstrating the storage case which concerns on another embodiment of this invention. It is a perspective view for demonstrating the cell which concerns on another embodiment of this invention.

Explanation of symbols

,
10 .... Battery,
20 ・ ・ Laminated part,
22. Clip hardware,
30 ・ ・ Storage case,
32 .. Stopper means,
34 .. Through hole,
36..End,
38..Junction part,
40 ・ ・ Top surface,
42 .. Upper surface extension,
44 .. notches,
46 .. opening,
48 .. Extension part,
50 ・ ・ Bottom surface,
52 .. Lower surface extension,
54 .. notches,
56 .. opening,
60, 70 ... cell,
62 .. Exterior case,
63 .. Heat welding part,
63 .. convex part,
65, 67, 75, 77 .. Electrode tab,
80 .. Support plate,
82 .. hole,
85..Pressing plate,
87 .. Through hole,
90 .. Holding means,
92. Locate pin,
92 .. Screw part,
95.Nut.

Claims (19)

An assembled battery in which a plurality of unit cells stacked are incorporated,
Having a plurality of storage cases having flexibility and electrical insulation for storing the unit cells;
The said storage case, the positioning means about the stacking direction is formed,
The assembled battery according to claim 1, wherein the positioning means is a through-hole or a protrusion and a recess that fit into each other .   The assembled battery according to claim 1, wherein the storage case has a bag shape.   The assembled battery according to claim 1 or 2, wherein the storage case stores a plurality of stacked unit cells, and the plurality of unit cells are connected in series.   The assembled battery according to any one of claims 1 to 3, wherein the unit cell includes electrode tabs having different polarities extending from opposing end surfaces.   The assembled battery according to claim 4, wherein the storage case stores a pair of unit cells in which one electrode tab is connected in advance to each other.   The assembled battery according to claim 5, wherein the storage case has a short-circuit preventing unit for insulating the other electrode tabs of the pair of unit cells from each other.   The short-circuit prevention means has an apron-like extension portion extending from an end portion of the storage case where the other electrode tab is disposed, and the extension portion is bent, and the other electrode tab of the pair of unit cells The assembled battery according to claim 6, wherein the battery pack is disposed between the two.   The assembled battery according to claim 5, wherein the storage case has stopper means for storing the pair of unit cells.   The assembled battery according to claim 8, wherein the stopper means includes a joint portion formed by partially joining upper and lower surfaces constituting the storage case.   The said storage case is laminated in multiple numbers, The other electrode tab of a pair of unit cell accommodated in the adjacent storage case is connected in series by the clip metal fitting. The assembled battery according to any one of the above.   The assembled battery according to claim 10, further comprising protection means for preventing the clip metal fitting from falling off and insulating the electrode tab connected by the clip metal fitting.   The protection means has an apron-like extension portion extending from an end portion of the storage case in which the other electrode tab is disposed, and the extension portion is bent and covers the clip metal fitting and the electrode tab, and is adjacent to the extension portion. The assembled battery according to claim 11, wherein the assembled battery is joined to a storage case.   The assembled battery according to any one of claims 1 to 12, wherein the storage case has a cut portion for pulling out an electrode tab of the unit cell.   The storage case has an apron-like extension for covering the electrode tab drawn out from the notch, and the extension is rolled up when connecting the electrode tab. Item 14. The assembled battery according to Item 13. Said positioning means, the battery pack according to any one of claims 1 to 14, characterized in that it comprises a through-hole formed in the housing case. It has a support plate on which the storage case is placed, the positioning means has a locating pin having one end fixed to the supporting plate, and the locating pin is aligned with the through hole. The assembled battery according to claim 15 . It has a pressing plate that is placed in the uppermost storage case and has a through hole through which the other end of the locate pin passes, and the other end of the locate pin has a threaded portion,
The pressing plate, by tightening the nut on the threaded portion of the other end of the locating pin, according to claim 16, characterized in that the storage case is placed on the support plate, under pressure and fixed Battery pack. The storage case is assembled battery according to any one of claims 1 to 17, characterized in that it has an opening for releasing the heat generated from the unit cells. The assembled battery according to any one of claims 1 to 18 , wherein the storage cases are connected in parallel.

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