JP5296989B2 - Electrical device assembly - Google Patents

Description

  The present invention relates to an electric device assembly in which a plurality of film-covered electric devices in which chargeable / dischargeable electric device elements are covered with a film are accommodated in a case.

  In recent years, development of electric vehicles and hybrid electric vehicles (hereinafter simply referred to as “electric vehicles”) using an electric motor as a drive source has been rapidly advanced. The power source of the electric motor mounted on the electric vehicle is required to be small and light in order to improve the driving characteristics of the electric vehicle or the like, the travel distance by one charge, and the like. In order to realize a power supply that meets such requirements, a film-clad battery disclosed in Japanese Patent Application Laid-Open No. 2001-76691 has been developed. Also, battery packs (sometimes referred to as “assembled batteries”) have been developed in which a large number of the film-clad batteries are accommodated in a case so as to obtain a desired output voltage. FIG. 7 shows the basic structure of a film-clad battery disclosed in Japanese Patent Application Laid-Open No. 2001-76691. In this film-clad battery 100, a power generation element 101 composed of a positive electrode side active electrode, a negative electrode side active electrode, and an electrolytic solution is covered with a laminate film 102. The laminate film 102 is a film in which a metal film such as aluminum and a heat-sealable resin film are overlapped. Four opposing sides of the two laminated films 102 covering the power generation element 101 are welded in an airtight manner. Further, a film-like positive electrode terminal 103 is drawn out from one short side of the laminated film 102 which is welded, and a film-like negative electrode terminal 104 is drawn out from the other short side.

  When a battery pack in which a large number of film-clad batteries having the basic structure shown in FIG. 7 are housed in a case is mounted on a moving body such as an electric vehicle, there are the following problems. That is, the position of the film-clad battery in the case is displaced due to vibration generated during the movement of the moving body, or a crack is generated in the exterior of the film-clad battery. In particular, vibrations of 100 Hz or less are continuously generated while the electric vehicle is traveling. When this frequency matches the natural frequency of the film-clad battery (when it resonates), a very large impact is applied to the film-clad battery as compared to when it is not resonant, and thus the above problem is likely to occur.

  An object of the present invention is to provide an electric device assembly having a structure in which vibration of a case and vibration of a film-covered electric device housed in the case hardly resonate.

  The present invention is characterized in that an elastic body is interposed between a film-clad electrical device and a case in which the film-clad electrical device is accommodated. This elastic body attenuates vibrations transmitted to the film-covered electrical device, and prevents resonance between the case and the film-covered electrical device.

One of the film-clad electrical devices of the present invention includes a plurality of film-clad electrical devices in which chargeable / dischargeable electrical device elements are covered with a film, and a plurality of flat plate-like plurality in which the plurality of film-clad electrical devices are individually accommodated. And a plurality of cell cases stacked and accommodated in a state where the plate surfaces face each other, wherein the plurality of cells are mounted on a mounting surface to which the body case is fixed. The main body case in which the plurality of cell cases are accommodated, and the cell case and the main body case are interposed along the stacking direction of the plurality of cell cases so that the case stacking directions are parallel to each other. And an elastic body disposed over the plurality of cell cases .

Another one of the film-clad electrical devices of the present invention is a flat-plate shape in which a plurality of film-clad electrical devices in which chargeable / dischargeable electrical device elements are covered with a film and the plurality of film-clad electrical devices are individually accommodated. A plurality of cell cases, a plurality of module cases in which a predetermined number of the cell cases are stacked and accommodated in a state where the respective plate surfaces face each other, and a main body case in which the plurality of module cases are accommodated. A main body case in which the plurality of module cases are accommodated so that a stacking direction of the plurality of cell cases is parallel to a mounting surface to which the main body case is fixed, and the module case and the main body in between the case interposed along the stacking direction of the plurality of cell casing, disposed over said plurality of cell case And a sex body.

  A plurality of cell cases accommodated in the module case can be fixed by being sandwiched between a side plate and a cover plate of the module case. Furthermore, a fixing member can be penetrated and integrated with a plurality of cell cases accommodated in the module case.

  The film-clad electrical device includes a film-clad battery in which a power generation element having a positive electrode side active electrode, a negative electrode side active electrode, and an electrolyte solution is hermetically covered with two laminate films.

It is an external appearance perspective view of a film-clad battery. It is a disassembled perspective view of a film battery with a case. It is a disassembled perspective view of a battery module. It is a disassembled perspective view of a battery pack. It is a perspective view in the state where the upper case of the battery pack was removed. It is sectional drawing which shows the fixation structure of a battery module and a main body case. It is an external appearance perspective view of the conventional film-clad battery.

  Hereinafter, an example of an embodiment of the electrical device assembly of the present invention will be described in detail. The electric device assembly of the present example is a battery in which a plurality of battery modules in which a plurality of film-clad batteries (film-clad electric devices) are integrated are accommodated in a case via elastic bodies such as rubber and resin. It is a pack.

  The film-clad battery constituting the battery pack of this example will be described with reference to FIG. A film-clad battery 10 shown in FIG. 1 is a secondary battery in which a power generation element 11 having a positive electrode side active electrode, a negative electrode side active electrode, and an electrolyte solution (not shown) is hermetically packaged by two laminate films 12. The output voltage of the film-clad battery 10 is about 3.6V. The laminate film 12 is a film in which a metal film such as aluminum and a heat-sealable resin film are overlapped. Four opposing sides of the two upper and lower laminate films 12 covering the power generation element 11 are hermetically welded.

  The power generation element of the film-clad battery includes a laminated type and a wound type. In the stacked power generation element, independent positive electrode side active electrodes and negative electrode side active electrodes are stacked via a separator. On the other hand, in a wound power generation element, a strip-like positive electrode side active electrode and a negative electrode side active electrode stacked via a separator are wound and compressed into a flat shape. However, the stacked type and the wound type are the same in that the positive electrode side active electrode and the negative electrode side active electrode are alternately stacked. The power generation element 11 of the film-clad battery 10 shown in FIG. 1 may be either a laminated type or a wound type. Furthermore, a positive electrode plate and a negative electrode plate which are used in a general lithium ion secondary battery can be used for the positive electrode side active electrode and the negative electrode side active electrode. A general positive electrode plate is coated with a positive electrode active material such as lithium-manganese composite oxide or lithium cobaltate on both surfaces such as an aluminum foil. A general negative electrode plate is coated with a carbon material capable of being doped / undoped with lithium on both sides of a copper foil or the like. Therefore, the power generation element 11 shown in FIG. 1 can be obtained by impregnating the general positive electrode plate and negative electrode plate opposed to each other with the separator between them with an electrolyte containing a lithium salt. However, the power generation element 11 is not limited to a specific power generation element, and any power generation element may be used as long as it includes a positive electrode, a negative electrode, and an electrolyte. For example, any power generation element used in a normal battery can be used as it is or after being appropriately changed in design.

  Refer to FIG. 1 again. From one short side of the film-clad battery 10, a positive electrode terminal 13 connected to the positive electrode side active electrode is drawn, and from the other short side, a negative electrode terminal 14 connected to the negative electrode side active electrode is drawn. Has been pulled out. The materials of the positive electrode terminal 13 and the negative electrode 14 are selected in consideration of electrical characteristics. In the film-clad battery 10 shown in FIG. 1, aluminum is used for the positive electrode terminal 13 and copper or nickel is used for the negative electrode terminal 14.

  In the battery pack of this example, the film-clad batteries 10 having the above structure are accommodated in the cell case 20 one by one. Furthermore, a predetermined number of film-clad batteries 10 (hereinafter referred to as “cased film batteries 21”) housed in the cell case 20 are integrated to form a battery module 30. Therefore, the structure of the cell case 20 is shown in FIG. 2, and the structure of the battery module 30 is shown in FIG.

  As shown in FIG. 2, the cell case 20 includes a case main body 21 and a frame body 22. The case body 21 includes a frame-shaped bottom plate 23 and side walls 24 raised from the periphery of the bottom plate 23. The side wall 24 has a shape and a dimension capable of accommodating the film-clad battery 10 shown in FIG. On the other hand, the frame body 22 has a shape and dimensions that can be fitted inside the side wall 24 of the case body 21. When the frame body 22 is placed on the film-covered battery 10 accommodated in the case body 21, the periphery of the film-covered battery 10 is sandwiched between the bottom plate 23 of the body case 21 and the frame body 22. Seven through holes 25 are formed in the bottom plate 23 of the case body 21. These through holes 25 are formed at positions that do not overlap with the film-clad battery 10 housed in the case body 21 and the frame body 22 covered on the film-clad battery 10. In other words, the opening position of the through hole 25 is designed to communicate with the front and back surfaces of the film battery 21 with case. Note that the positive electrode terminal 13 and the negative electrode terminal 14 of the film-clad battery 10 accommodated in the cell case 20 are respectively drawn out of the cell case 20 through two notches 26 provided on the short side of the case body 21. It is.

  Next, the battery module 30 will be described. As shown in FIG. 3, the battery module 30 includes a plurality of cased film batteries 21 housed in a module case, and the plurality of cased film batteries 21 housed therein are integrated. The module case includes a resin holding member 31 and a cover plate 32. Twelve cased film batteries 21 are accommodated in the module case.

  The module case holding member 31 includes a side plate 33 and arms 34 protruding from the four corners of the side plate 33 toward the cover plate 32. Further, substantially L-shaped guide grooves 35 into which the four corners of the case-equipped film battery 21 (cell case 20) and the cover plate 32 can be respectively fitted are formed inside each arm 34 along the longitudinal direction. The twelve case-cased film batteries 21 are accommodated inside the four arms 34 according to the guide of the guide groove 35 and are stacked in the thickness direction of the cell case 20.

  The cover plate 32 is fitted inside the four arms 34 according to the guidance of the guide grooves 35 after the twelve cased film batteries 21 are accommodated inside the arms 34. The fitted lid plate 32 is in contact with the cased film battery 21a closest to the stacking direction. Here, the length of the arm 34 is longer by the thickness of the cover plate 32 than the total thickness of the twelve cased film batteries 21. Therefore, the surface of the cover plate 32 fitted inside the arm 34 next to the twelve case-cased film batteries 21 and the end surface of the arm 34 are flush with each other. A number of ribs are formed on the surfaces of the side plate 33 and the arm 34 for reinforcement.

  The side plate 33 of the holding member 31 is formed with a plurality of rod insertion holes 36 that communicate with the through holes 25 (see FIG. 2 for details) provided in each cell case 20. The lid plate 32 also has a plurality of bolt insertion holes 37 that communicate with the through holes 25. A rod 38 as a fixing member inserted from the rod insertion hole 36 of the holding member 31 passes through all the cased film batteries 21 and reaches the bolt insertion hole 37 of the lid plate 32. The rod 38 is an elongated hollow, and a screw (not shown) is formed on the inner peripheral surface thereof. A bolt 39 inserted into the bolt insertion hole 37 from the opposite side to the rod 38 is screwed to one end of the rod 38 that has reached the bolt insertion hole 37. That is, the holding member 31, the twelve cased film batteries 21 and the cover plate 32 are integrated (modularized) by seven rods 38 penetrating them.

  A rectangular head 40 is formed at the other end of the rod 38, and a rectangular recess (not shown) into which the head 40 can be fitted is formed at the periphery of the rod insertion hole 36. By fitting the head portion 40 of the rod 38 into the recess, the rod 38 is prevented from co-rotating when the bolt 39 is screwed to one end of the rod 38. The depth of the recess is not less than the thickness of the head 40 so that the head 40 fitted in the recess does not protrude from the surface of the side plate 33. Further, the head 41 of the bolt 39 can be fitted to the periphery of the bolt insertion hole 37 of the cover plate 32 so that the head 41 of the bolt 39 screwed to the rod 38 does not protrude from the surface of the cover plate 32. A recess is formed.

  The inner diameter of the bolt insertion hole 37 is smaller than the outer diameter of the rod 38. Therefore, the tip of the rod 38 penetrating the cased film battery 21 a in contact with the cover plate 32 is not inserted into the bolt insertion hole 37. This means that the distance between the side plate 33 and the cover plate 32 of the holding member 31 sandwiching the plurality of cased film batteries 21 can be defined by the length of the rod 38. Furthermore, since the metal rod 38 has higher dimensional accuracy than the resin holding member 31 and the cover plate 32, it means that the distance between the side plate 33 and the cover plate 32 can be defined more accurately. To do. In addition, the fact that the distance between the side plate 33 and the cover plate 32 is accurately defined means that the plurality of cased film batteries 21 therebetween are pressed in the stacking direction by a uniform pressure.

  The twelve cased film batteries 21 modularized as described above are connected in series via a bus bar 42 spanned between the upper and lower arms 34. Therefore, the output voltage of one battery module 30 is about 43V. However, the number of cased film batteries 21 constituting each battery module 30 is not limited to twelve. However, since humans are said to be able to escape instant death due to electric shock if it is 50 V or less, from the viewpoint of safety, the number that the output voltage is 50 V or less is desirable.

  As shown in FIGS. 4 and 5, in the battery pack 50 of this example, eight battery modules 30 shown in FIG. 3 are accommodated in a main body case 51. The main body case 51 includes a lower case 52 on which the battery module 30 is mounted, an upper case 53 that covers the battery module 30 mounted on the lower case 52, and a case lid that closes one longitudinal opening of the upper case 53. 54. The other opening in the longitudinal direction of the upper case is closed by a relay box 55. In other words, the eight battery modules 30 are accommodated in the main body case 51 in a state of being arranged in a line between the lid plate 54 and the relay box 55. The relay box 55 accommodates fuses, relays, current sensors, and the like. In FIG. 4, the upper case 53, the cover plate 54, and the relay box 55 are not shown for convenience.

  Further, as shown most clearly in FIG. 4, a pair of lower rubber sheets 56 are provided between the bottom surface of the battery module 30 and the lower case 52, and the upper surface of the battery module 30 and the upper cover 53 (not shown). A pair of upper rubber sheets 57 are disposed between the two. More specifically, between the bottom surface of the battery module 30 and the lower case 52, two elongated lower rubber sheets 56 are arranged in parallel at a predetermined interval along the arrangement direction of the battery modules 30. The lower rubber sheet 56 is in close contact with the bottom surface of the battery module 30 and the lower case 52. On the other hand, between the upper surface of the battery module 30 and the upper case 53, two upper rubber sheets 57 that are elongated along the arrangement direction of the battery modules 30 are arranged in parallel at a predetermined interval. The upper rubber sheet 57 is in close contact with the upper surface of the battery module 30 and the upper case 53.

  The eight battery modules 30 housed in the main body case 51 in the state as described above include a plurality of stepped bolts 60 that penetrate the lower case 52 and the lower rubber sheet 56 or the upper case 53 and the upper rubber sheet 57. Is fixed to the main body case 51. The stepped bolt 60 has a head on which a flange 64 is formed, a shaft portion 65, and a tip portion thinner than the shaft portion 65. A screw 62 is formed on the outer peripheral surface of the tip of the stepped bolt 60. The structure for fixing the main body case 51 and the battery module 30 with the stepped bolts 60 is substantially common to all the stepped bolts 60. Accordingly, FIG. 6 shows a structure for fixing the battery module 30 and the main body case 51 with any one stepped bolt 60.

  FIG. 6 shows a fixing structure between the upper case 53 and any one battery module 30. The shaft portion 65 of the stepped bolt 60 inserted from the hole 61 provided in the upper case 53 passes through the upper rubber sheet 57. Further, the screw 62 of the stepped bolt 60 formed at the tip of the shaft portion 65 is screwed into a bolt hole 63 formed on the upper surface of the battery module 30. On the other hand, the flange 64 formed on the head of the stepped bolt 60 is in close contact with the periphery of the hole 61 of the upper case 53. That is, the upper rubber sheet 57 is restricted from moving in the vertical direction by the upper case 53 and the battery module 30, and is restricted from moving in the horizontal direction by the stepped bolt 60. 30 is not directly fixed.

In the battery pack 50 of this example, when the main body case 51 vibrates, the vibration is attenuated by the upper and lower rubber sheets 56 and 57. Therefore, if the natural frequency of the battery module 30 is set to be equal to or higher than the expected frequency of the main body case 51, it is almost certainly ensured that the frequency of the main body case 51 matches the natural frequency of the battery module 30. It can be avoided. Accordingly, the resonance between the main body case 51 and the battery module 30 can be avoided with certainty. For example, when the battery pack 50 is mounted on an electric vehicle, the expected main frequency of the main body case 51 is 100 Hz or less. Therefore, if the natural frequency of the battery module 30 is set to 100 Hz or more, resonance between the main body case 51 and the battery module 30 can be avoided almost certainly. Here, rubber hardness is one of the parameters that define the amount of vibration attenuation by the upper and lower rubber sheets 56 and 57. It is possible to select a suitable hardness for the rubber hardness in consideration of the expected frequency of the main body case 51 and other conditions. In this example, the hardness is 60 (JIS
Hs hardness) rubber sheet was used.

  The battery pack 50 of this example is fixed to a mounting surface (not shown) using a fixing bracket 70 (FIGS. 4 and 5) protruding from the long side of the lower case 52. At this time, the lower case 52 can be rigidly fixed to the mounting surface or can be fixed in a floating state. When it is difficult for the upper and lower rubber sheets 56 and 57 alone to attenuate the frequency of vibration transmitted to the battery module 30 below the natural frequency of the battery module 30, fixing in the floating state is desirable. The fixation in the floating state means a fixed state in which the mounting surface and the main body case 51 are fixed via an elastic body such as rubber so that vibrations on the mounting surface are not directly transmitted to the main body case 51.

  The eight battery modules 30 integrated with the main body case 51 as described above are connected in series. Specifically, the four battery modules 30 connected in series and the other four battery modules 30 connected in series are further connected in series via a safety plug in the relay box 50. Therefore, the output voltage of the battery pack 50 is about 350V.

  The plurality of film-clad batteries accommodated in the main body case 51 are not necessarily modularized. The case-cased film battery 21 shown in FIG. 2 can be directly accommodated in the main body case 51. When the case-containing film battery 21 is directly accommodated in the main body case 51, a lower rubber sheet 56 is interposed between the bottom surface of the cell case 20 and the lower case 52, and the space between the upper surface of the cell case 20 and the upper case 53. An upper rubber sheet 57 can be interposed between the upper rubber sheet 57 and the upper rubber sheet 57.

  The embodiments of the present invention have been described so far by taking the case where the film-clad electrical device is a film-clad battery as an example. However, the film-clad electrical device constituting the electrical device module or the electrical device module assembly of the present invention is not limited to a film-clad battery. For example, a film-covered electric device in which an electric device element (for example, a capacitor element typified by an electric double layer capacitor or an electrolytic capacitor) capable of storing electric energy is coated with a covering film is also included.

  In the present invention, two or more cell cases in which the film-clad electrical devices are individually accommodated are accommodated in the main body case via the elastic body. Therefore, when the main body case vibrates, the vibration is attenuated by the elastic body and transmitted to the cell case. Therefore, if the natural frequency of the cell case is set to be equal to or higher than the expected frequency of the main body case, resonance between the main body case and the cell case is almost certainly avoided.

Claims (6)

A plurality of film-covered electrical devices in which chargeable / dischargeable electrical device elements are covered by a film;
A plurality of flat cell cases in which the plurality of film-covered electrical devices are individually accommodated,
The plurality of cell cases are stacked and accommodated in a state where the respective plate surfaces face each other , and the stacking direction of the plurality of cell cases is relative to the mounting surface to which the main body case is fixed. A main body case in which the plurality of cell cases are accommodated so as to be parallel ;
Between the cell case and the main body case, interposed along the stacking direction of the plurality of cell cases, and an elastic body disposed over the plurality of cell cases ,
An electrical device assembly having: A plurality of film-covered electrical devices in which chargeable / dischargeable electrical device elements are covered by a film;
A plurality of flat cell cases in which the plurality of film-covered electrical devices are individually accommodated,
A plurality of module cases in which a predetermined number of the cell cases are stacked and accommodated in a state where the respective plate surfaces face each other ;
A main body case in which the plurality of module cases are accommodated, wherein the plurality of module cases are accommodated such that a stacking direction of the plurality of cell cases is parallel to a mounting surface to which the main body case is fixed. The main body case ,
Between the module case and the main body case, interposed along the stacking direction of the plurality of cell cases, and an elastic body disposed over the plurality of cell cases ,
An electrical device assembly having: The module case has a holding member provided with a side plate that contacts the cell case at one end in the stacking direction, and a lid plate that contacts the cell case at the other end in the stacking direction.
The electrical device according to claim 2, wherein two or more fixing members inserted from insertion holes provided in the holding member or the lid plate penetrate the plurality of cell cases in the module case in the stacking direction. Aggregation.   2. The electric device assembly according to claim 1, wherein the film-clad electrical device is a film-clad battery in which a power generation element having a positive electrode side active electrode, a negative electrode side active electrode, and an electrolyte solution is hermetically covered with two laminated films. .   3. The electric device assembly according to claim 2, wherein the film-clad electrical device is a film-clad battery in which a power generation element having a positive electrode side active electrode, a negative electrode side active electrode, and an electrolyte solution is hermetically covered with two laminated films. .   The electric device assembly according to claim 3, wherein the film-clad electrical device is a film-clad battery in which a power generation element having a positive electrode side active electrode, a negative electrode side active electrode, and an electrolyte solution is hermetically covered with two laminated films. .

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