JP2010186786A - Electrical storage device and electrical storage device module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrical storage device provided with a cleavage jig capable of surely discharging a gas generated in the inside to the outside before lamination coating is largely deformed by the gas without inviting enlargement. <P>SOLUTION: A storage 15 comprises a laminated film, has two or more sets of a positive plate 3, a negative plate 6 and a separator 7 laminated and incorporated in the inside, has electrolyte 9 which is injected and sealed, and is formed in a roughly planar shape on the appearance. On at least one side face 15a of a storage 15, the cleavage jig 20, which is formed in a roughly prismatic shape on the appearance along the side face, has a recess 21 opened toward the side face 15a and formed in the inside, and has a projection 22 capable of puncturing the side face when the side face 15a is swollen inside the recess 21 by being projected to the side of the side face 15a on the inner wall of the recess 21 and having a gap between the distal end and the side face 15a, is fixed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electricity storage device having an exterior made of a laminate film such as a capacitor or a secondary battery, and more specifically, an electricity storage device having a mechanism for smoothly discharging gas generated in the laminate exterior and a plurality of the electricity storage devices It relates to a module using a device.

  In recent years, lithium-ion capacitors, which are a type of energy storage device, are capable of rapid charge and discharge and a desired energy capacity even though they are smaller and lighter than conventional batteries. In addition, it is being used in a wide range of fields such as a load leveling device for wind power generation, a voltage sag countermeasure device, a backup power supply device for a hybrid electric vehicle, a fuel cell vehicle, and the like.

  Such a lithium ion capacitor generally forms a plurality of plate-like positive electrode plates with positive electrodes formed on both sides of the current collector and a negative electrode made of a material capable of inserting and extracting lithium ions on both sides of the current collector. After laminating a plurality of flat plate-like negative electrode plates alternately with separators in between, and applying a load in the compression direction between both end portions of the obtained laminate, the synthetic resin such as polyethylene is used. It is arranged in an exterior made of a laminate film made by laminating a sheet made of metal and a metal foil such as aluminum foil, and an electrolyte containing a lithium salt is injected between them and the inside is vacuum-sealed. Has been.

By the way, in the electric storage device such as the lithium ion capacitor, gas is generated due to decomposition of the internal electrolyte due to charge charging or the like. And as a result of this gas filling up inside and expanding the laminate exterior, a large deformation occurs, and finally the gas bursts and the gas is ejected or leaks. appear.
For this reason, in general, the electricity storage device is provided with a mechanism for discharging the internal gas when the laminate sheath expands.

  For example, in Patent Document 1 below, a lithium battery in which a unit cell including a positive electrode and a negative electrode capable of inserting and extracting lithium ions and a lithium ion conductive electrolyte layer interposed between the positive and negative electrodes is sealed with a laminate film. The secondary battery is housed in a resin case, and a recess is formed on the inner surface of the resin case. A sharp protrusion is formed in the recess, and its tip is slightly closer to the recess than the inner surface of the resin case. A battery pack formed to be positioned has been proposed.

Japanese Patent Laid-Open No. 10-208720

  However, in the gas discharging mechanism in the above conventional power storage device, the lithium secondary battery sealed with the laminate film is further housed in the resin case, so that the entire battery pack is enlarged. In particular, when a module is configured by combining a plurality of lithium secondary batteries, the entire module becomes bulky, which goes against the recent demand for miniaturization.

  Also, since the protrusion is formed in the recess formed on the inner surface of the resin case, the tip is located in the recess, so that the expanded laminate film can penetrate into the recess and be perforated by the protrusion. However, there is also a problem that it is difficult to set the size of the recess and the tip position of the protrusion.

  The present invention has been made in view of such circumstances, and it is possible to reliably release the gas to the outside without causing an increase in size and before a large deformation occurs in the laminate exterior due to the gas generated inside. It is an object of the present invention to provide an electricity storage device provided with a cleavage jig to be and an electricity storage device module combining a plurality of the electricity storage devices.

  In order to solve the above-described problem, the electricity storage device according to claim 1 is configured such that a positive electrode plate in which a positive electrode is formed on both surfaces of a current collector and a negative electrode on both surfaces of the current collector are formed in a storage portion made of a laminate film. A plurality of negative electrode plates stacked and incorporated with a separator interposed therebetween, and an electrolyte solution is injected and sealed, and the storage portion has wide upper and lower surfaces along the positive electrode plate and the negative electrode plate, In the electricity storage device formed in a substantially flat outer appearance having four side surfaces located between the upper and lower surfaces, formed in a substantially rectangular column shape along the side surface on at least one side surface of the storage portion, A concave portion that opens toward the side surface is formed, the inner wall of the concave portion projects toward the side surface side, and a gap is formed between the tip and the side surface, so that the side surface becomes the concave portion. Bulged in The pierceable protruding portion is provided on a side surface opening 裂治 device is characterized in that become fixed to.

  Here, the invention described in claim 2 is characterized in that, in the invention described in claim 1, the cleavage jig is formed with a gas vent for communicating the inside of the recess to the outside. It is.

  Furthermore, the invention according to claim 3 is the invention according to claim 1 or 2, wherein the laminate film has a substantially flat-shaped storage portion that stores the positive electrode plate, the negative electrode plate, and the separator by drawing, A flange that surrounds the storage portion is formed, a terminal connected to the current collector of the positive electrode plate is extended to one end in the longitudinal direction, and a collector of the negative electrode plate is connected to the other end. When the terminal connected to the electric body is extended to the outside, the flange portion located at both ends in the longitudinal direction has a non-adhesive portion sandwiching the connecting portion between the current collector and the terminal. A sealing portion on the outer peripheral side of the non-adhesive portion is formed, and the cleavage jig is at least one of the one end portion and the other end portion in the longitudinal direction and fixed on the flange portion. It is characterized by this.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, the flange is formed at an intermediate portion in the thickness direction of the storage portion, and the two cleavage jigs are the ribs. The cleavage jig is fixed by a band wound between the outer circumferences of the two parts or a resin mold that covers the outer circumference of the storage part. .

  And the electrical storage device module of Claim 5 is laminated | stacked by making the said electrical storage device in any one of Claims 1-4 contact | abut the said upper and lower surfaces of the said storage part, and at least said storage It is fixed in the thickness direction of the part.

  In the electricity storage device according to any one of claims 1 to 4, a plurality of positive electrode plates, negative electrode plates, and separators are stacked and incorporated, and an electrolyte is injected and sealed, and the outer appearance is formed in a substantially flat plate shape. Since the cleavage jig is fixed to at least one side surface of the storage portion made of the laminated film, the electricity storage device including the cleavage jig is configured without increasing the overall thickness dimension. Can do.

  Then, a recess that opens toward the side surface is formed inside the cleavage jig, and the inner wall of the recess projects toward the side surface, and a gap is formed between the tip and the side surface. When the expanded laminate film penetrates into the recess when gas is generated in the storage portion and the expanded laminate film enters the recess, the storage portion is opened by the protrusion. The gas can be discharged to the outside before it is greatly deformed.

  At this time, by perforating the laminate film, the gas generated in the storage unit is discharged into the recess of the cleavage jig and released to the outside through the gap between the cleavage jig and the storage unit. Although it is possible, if the gas vent which makes the inside of the said recessed part communicate with the exterior is formed in the said cleavage jig like invention of Claim 2, the said gas discharged | emitted in the recessed part more rapidly Can be discharged to the outside through the gas vent.

  Further, as in the invention described in claim 3, when a positive terminal or a negative terminal is extended at the end in the longitudinal direction of the storage portion, it is positioned at both ends in the longitudinal direction. A non-adhesive portion sandwiching a connecting portion between the positive current collector or the negative current collector and the terminal and a sealing portion on the outer peripheral side of the non-adhesive portion are formed on the flange portion. Yes.

  As a result, when gas is generated in the storage portion, first, at both ends in the longitudinal direction of the storage portion, the laminate film in the non-adhesive portion sandwiching the connection portion of the flange portion is expanded toward the upper surface side and the lower surface side. Put out.

  Therefore, if a cleavage jig is fixed on at least one of the end portions located at both ends in the longitudinal direction, the initial stage of gas generation before the deformation amount of the laminate film in the storage portion becomes large, In the non-bonded portion of the flange portion, the laminate film can be perforated by the protrusion of the cleavage jig, and the internal gas can be quickly discharged.

  In addition, although the said cleavage jig | tool can discharge | emit the gas generated inside by installing one with respect to one electrical storage device, like the invention of Claim 4, a collar part is In the case where it is formed in the intermediate part in the thickness direction of the storage part, the two cleavage jigs are provided with the collar part in between, and these cleavage jigs are wound around the outer periphery of both. If it is fixed by a resin mold that covers the outer periphery of the band or the storage part, even if the laminate film in that part expands and deforms, it does not cause misalignment or lifting, etc., in both cleavage jigs. In addition, the laminate film can be perforated and gas can be discharged.

  From the above, even in the electricity storage device module according to claim 5, the same effect as the electricity storage device according to claims 1 to 4 can be obtained for each electricity storage device constituting the module.

  In addition, in the above module, a plurality of power storage devices are stacked with the wide upper and lower surfaces of each storage part in contact with each other, and are fixed in the thickness direction of the storage part. Even in this case, as a result of the expansion of the upper and lower surfaces of the storage unit being prevented, in the initial stage of gas generation, only the side surface of the storage unit is expanded, and the laminate film is perforated by the protrusion of the cleavage jig more reliably. The effect that it can be performed is acquired.

BRIEF DESCRIPTION OF THE DRAWINGS One Embodiment of the electrical storage device which concerns on this invention is shown, (a) is a top view, (b) is a front view. It is a perspective view which shows the cleavage jig | tool of FIG. It is a longitudinal cross-sectional view of FIG. It is a longitudinal cross-sectional view which shows the state when gas generate | occur | produces in the electrical storage device of FIG. It is a front view which shows the 1st modification of FIG. It is a front view which shows the 2nd modification of FIG. It is a front view which shows the 3rd modification of FIG. It is a front view which shows one Embodiment of the electrical storage device module which concerns on this invention. It is the front view which looked at the partial cross section which shows the modification of FIG. It is a top view which shows the 4th modification of FIG.

  1 to 4 show an embodiment in which an electricity storage device according to the present invention is applied to a lithium ion capacitor, and FIGS. 5 to 7 show first to third modifications thereof. .

  1 to 4, the lithium ion capacitor includes a plurality of positive plates 3 having positive electrodes 2 formed on both sides of a current collector 1 and a plurality of negative plates having negative electrodes 5 formed on both sides of a current collector 4. 6 are alternately laminated with separators 7 interposed between them and housed in an outer package 8 made of a laminate film, and an electrolytic solution 9 is injected into the interior and vacuum sealed. It is.

  Here, the current collector 1 of the positive electrode plate 3 is a metal foil (50 mm to 150 mm) × (50 mm to 150 mm) which has oxidation resistance and does not chemically elute such as nickel foil or aluminum foil having a thickness of 25 μm to 35 μm. 50 mm to 150 mm) is formed by punching into a rectangle, and when performing the punching process, a connecting tongue 1 a is integrally formed at one end in the longitudinal direction. The positive electrode 2 made of a carbon material made of activated carbon or the like is formed on both surfaces of the current collector 1.

  On the other hand, the current collector 4 of the negative electrode plate 6 is obtained by punching a copper foil having a thickness of 12 to 16 μm into a rectangular shape (50 mm to 150 mm) × (50 mm to 150 mm) that is substantially the same shape as the current collector 1 on the positive electrode side. Similarly, when performing the punching process, the connecting tongue 4a is integrated with the other end in the longitudinal direction opposite to the connecting tongue 1a of the current collector 1 on the positive electrode side. Is formed. And the said negative electrode 5 which has a non-graphitizable carbon material as a main component is formed in both surfaces of this electrical power collector 4. FIG.

  The separator 7 is made of a sheet material having liquid permeability and non-electron conductivity made of synthetic resin such as polyethylene and polypropylene, glass fiber, and the like, and the current collectors 1, 4 of the positive electrode plate 3 and the negative electrode plate 6. Is formed in a square having an outer dimension equal to or larger than

Further, as the electrolytic solution 9, a liquid containing a lithium salt such as LiBF ₄ , LiPF ₄ , LiClO ₄ , LiAsF ₆ is injected.
3 and 4, for convenience of illustration, three sets of positive electrode plates 3 and negative electrode plates 6 are alternately stacked and accommodated in the laminate case 8 with separators 7 interposed therebetween. However, in an actual product, 40 to 90 positive electrode plates 3 and negative electrode plates 6 are similarly accommodated with a separator 7 interposed therebetween.

  Such a large number of positive electrode plates 3 are connected to current collecting tabs (terminals) 10 serving as external connection terminals by laminating the connecting tongues 1a of the current collectors 1 and a large number of sheets. The negative electrode plate 6 is connected to a current collecting tab (terminal) 11 by laminating connection tongues 4 a of the current collectors 4.

  In this way, the plurality of stacked positive electrode plates 3, negative electrode plates 6 and separators 7 were accommodated, and the electrolyte solution 9 was injected and evacuated therein, and sealed at the sealing portion 18 on the outer peripheral portion. The exterior 8 is formed by drawing to form a substantially flat-shaped storage portion 15 that stores the positive electrode plate 3 and the like, and a flange portion 16 that surrounds the storage portion 15.

  As a result, a current collecting tab 10 connected to the current collector 1 of the positive electrode plate 3 is extended to one end in the longitudinal direction of the exterior 8 and the current collector 4 of the negative electrode plate 6 is connected to the other end. The connected current collecting tab 11 is extended outside.

  Further, the flange portions 16 located at both ends in the longitudinal direction from which the current collecting tabs 10 and 11 extend are sandwiched between the connecting portions between the connecting tongues 1a and 4a and the current collecting tabs 10 and 11, respectively. As a result, the non-adhesive part 17 where the opposing laminate films are not adhered to each other and the sealing part 18 where the opposing laminate films are adhered to each other on the outer peripheral side of the non-adhesive part 17 are formed.

The cleavage jig 20 is fixed along the side surface 15 a of the storage portion 15 on the flange portion 16 at one end portion in the longitudinal direction from which the current collecting tab 10 extends.
The cleaving jig 20 is formed of a hard material having a predetermined rigidity such as a metal or a synthetic resin into a substantially prismatic appearance having a length along the entire length of the side surface 15a.

  Here, a recess 21 is formed on the inner surface of the cleavage jig 20 so that the entire surface on the side surface 15a side and the flange portion 16 side is open, and the inner wall of the recess 21 intersects the side surface 15a and the flange portion 16. A flat blade-shaped cleavage blade (protrusion) 22 that protrudes toward the portion is integrally provided. Further, the cleavage blade 22 is formed to have a length dimension in which a gap is formed between the tip thereof, the side surface 15a and the flange portion 16.

  In addition, in this embodiment, although it has shown about the case where the cleavage blade 22 is provided, if it has the shape and intensity | strength which can tear a laminate film, it will be a projection part of various shapes, such as a needle shape and a saw blade shape. Can be provided.

  Further, in the cleavage jig 20, gas vents 23 that allow the recess 21 to communicate with the outside are formed at a plurality of locations (six locations in the drawing) at equal intervals in the longitudinal direction. The cleavage jig 20 is firmly bonded and fixed so that the peripheral edge portions 21 a and 21 b of the opening of the recess 21 are in close contact with the side surface 15 a and the flange portion 16, respectively.

  In the lithium ion capacitor provided with the cleavage jig 20 having the above-described configuration, a plurality of stacked positive electrode plates 3, negative electrode plates 6, separators 7, and electrolytes 9 are stored in a sealed outer package 8. Since the cleavage jig 20 is fixed to the side surface 15a of the portion 15, the electricity storage device including the cleavage jig can be configured without increasing the overall thickness dimension.

  Here, in particular, since the above-mentioned cleavage jig 20 is provided at the longitudinal end portion of the storage portion 15 from which the positive current collecting tab 10 extends, as shown in FIG. When the gas is generated, first, in the non-adhesive portion 17 of the flange portion 16 that sandwiches the connection portion between the connection tongue portion 1a and the current collecting tab 10, the gas enters between the opposing laminate films, and the side surface 15a and the non-adhesive portion are adhered. The laminated film of the part 17 bulges outward.

  The laminate film is cleaved by being pierced by the cleaving blade 22 of the cleaving jig 20, and the internal gas is discharged into the recess 21. Further, the gas in the recess 21 is quickly discharged from the gas vent 23 to the outside of the cleavage jig 20.

  Thus, according to the lithium ion capacitor provided with the above-described cleavage jig 20, when gas is generated in the storage portion, the gas is surely supplied to the outside in the initial stage before large deformation occurs in the laminate exterior. Can be released.

  In addition, although the cleavage jig | tool 20 can discharge | emit the gas generated inside by installing one with respect to one lithium ion capacitor like what was shown in FIGS. 1-4, If the two cleavage jigs 20 are provided with the flange 16 in between as in the first to third modifications shown in FIG. 5 to FIG. 7, the end portion can be more reliably obtained in the initial stage of gas generation. The laminate film that bulges in can be cleaved to discharge the internal gas.

  Further, as in the second modification shown in FIG. 6 in particular, if the two cleavage jigs 20 sandwiching the flange portion 16 are fixed by a band 25 wound between the outer circumferences of the two, the laminate film can be obtained. Even when the film is expanded and deformed, the laminate film can be perforated and the gas can be discharged without causing misalignment or lifting of the two cleavage jigs 20.

  Further, as in the third modification shown in FIG. 7, a resin mold 26 is formed on the outer periphery of the storage portion 15 to cover the storage portion, and the two cleavage jigs 20 are attached to the periphery of the opening of the resin mold 26. In addition to the effects shown in FIG. 6, in the case where gas is generated inside the exterior 8, the expansion of the upper and lower surfaces of the storage portion 15 is prevented, so that in the initial stage of gas generation. Only the side surface 15a of the storage portion 15 is expanded, and the laminate film can be perforated by the cleavage blade 22 of the cleavage jig 20 more reliably.

  Next, FIG. 8 and FIG. 9 show an embodiment in which the electricity storage device module according to the present invention is applied to a lithium ion capacitor module (hereinafter simply referred to as a module) and its modifications. Note that the configurations of the lithium ion capacitor and the cleavage jig 20 are the same as those shown in FIGS.

  As shown in FIG. 8, this module stacks four sets of lithium ion capacitors having the two cleavage jigs 20 shown in FIG. The cleavage jigs 20 are fixed to each other in the thickness direction (lamination direction) by a band 30.

  Further, in the module shown in FIG. 9, the entire outer periphery of the storage unit 15 of four sets of lithium ion capacitors laminated in the same manner is covered with the resin mold 31 and the eight peripheral edges of the opening of the resin mold 31 are used for the eight cleavage treatments. The tool 20 is integrally held.

  According to these modules, in addition to the same effects as those shown in FIGS. 1 to 4 for each lithium ion capacitor constituting the module, it is further shown in FIG. 6 or FIG. Similarly to the above, as a result of the expansion of the upper and lower surfaces of the storage unit 15 being prevented, only the side surface 15a of the storage unit 15 is expanded in the initial stage of gas generation, thereby further reliably The laminate film 22 can be perforated.

  In the above embodiment, the case where the electricity storage device according to the present invention is applied only to a lithium ion capacitor has been described. However, the present invention is not limited to this, and a plurality of positive electrode plates arranged opposite to each other with a separator interposed therebetween. The present invention can be similarly applied to other power storage devices such as a lithium ion secondary battery having a laminate exterior in which an electrolytic solution containing a lithium salt is injected between and sealed with a negative electrode plate.

  Moreover, in the said electrical storage device and a module using the same, all are formed in the length dimension along the full length of the side surface 15a of the accommodating part 15, and the recessed part 21 which the whole surface by the side 15a side and the collar part 16 side opens. However, the present invention is not limited to these, and for example, as shown in FIG. 10, the length is shorter than the entire length of the side surface 15a. It is also possible to use a cleaving jig 40 in which a recess 41 is formed in the entire surface or part of the side surface 15a.

DESCRIPTION OF SYMBOLS 1 Current collector on the positive electrode side 1a, 4a Connection tongue 2 Positive electrode 3 Positive electrode plate 4 Current collector on the negative electrode side 5 Negative electrode 6 Negative electrode plate 7 Separator 8 Exterior 10 Current collection tab (terminal) on the positive electrode side
11 Negative current collector tab (terminal)
DESCRIPTION OF SYMBOLS 15 Storage part 15a Side surface 16 Gutter part 17 Non-adhesion part 18 Sealing part 20, 40 Cleavage jig 21, 41 Recessed part 22 Cleavage blade (protrusion part)
25, 30 Band 26, 31 Resin mold

Claims (5)

A plurality of sets of a positive electrode plate having a positive electrode formed on both sides of a current collector and a negative electrode plate having a negative electrode formed on both sides of the current collector are stacked and incorporated in a storage portion made of a laminate film with a separator interposed therebetween. The electrolytic solution is injected and sealed, and the storage portion is formed in a substantially flat plate appearance having a wide upper and lower surface along the positive electrode plate and the negative electrode plate, and four side surfaces located between the upper and lower surfaces. In the stored electricity storage device,
At least one of the side surfaces of the storage portion is formed in a substantially prismatic appearance along the side surface, and a recess is formed in the interior toward the side surface, and the inner wall of the recess is directed toward the side surface side. When the side surface bulges into the recess, a cleavage jig provided with a projecting portion that can be perforated is fixed when the side surface bulges into the recess. An electricity storage device characterized by being made.   The electricity storage device according to claim 1, wherein the cleaving jig is formed with a gas vent for communicating the inside of the recess to the outside. The laminate film is formed with a substantially flat-shaped storage portion that houses the positive electrode plate, the negative electrode plate, and the separator by drawing, and a collar portion that surrounds the storage portion, and at one end portion in the longitudinal direction. A terminal connected to the current collector of the positive electrode plate is extended to the outside, and a terminal connected to the current collector of the negative electrode plate is extended to the outside at the other end, so that both end portions in the longitudinal direction A non-adhesive part that sandwiches a connection part between the current collector and the terminal and a sealing part on the outer peripheral side of the non-adhesive part are formed in the collar part located at
The power storage device according to claim 1, wherein the cleavage jig is at least one of one end and the other end in the longitudinal direction and is fixed on the flange.   The flange portion is formed at an intermediate portion in the thickness direction of the storage portion, and the two cleavage jigs are provided with the flange portion interposed therebetween. The electricity storage device according to claim 3, wherein the electricity storage device is fixed by a band wound around or a resin mold covering an outer periphery of the storage portion.   A plurality of power storage devices according to any one of claims 1 to 4, wherein the upper and lower surfaces of the storage unit are in contact with each other, and are fixed at least in the thickness direction of the storage unit. An electricity storage device module.

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