Patent Publication Number: US-2020287198-A1

Title: Liquid Injection Device

Description:
TECHNICAL FIELD 
     The present invention relates to a liquid injection device including a nozzle to be inserted in a bag-shaped laminate film exterior, wherein gas inside the bag-shaped laminate film exterior is evacuated through the nozzle. 
     BACKGROUND ART 
     Patent Document 1 discloses a liquid injection device including an evacuation nozzle to be inserted in an opening of a laminate sheet bag containing a generation element, for producing a vacuum in the laminate sheet bag. 
     The liquid injection device according to Patent Document 1 includes the evacuation nozzle separately from a liquid injection nozzle. These nozzles are inserted in the opening of the laminate sheet bag. 
     In case that the evacuation is implemented with a tip of the evacuation nozzle relatively apart from the generation element, the liquid injection device may cause insufficient evacuation in the laminate sheet bag due to adhesion between laminate sheets in a region between the evacuation nozzle tip and the generation element. 
     Alternatively, in case that the evacuation is implemented with the evacuation nozzle tip inserted deeply to reach a vicinity of the generation element, the laminate sheet bag may deteriorate in sealability because the evacuation nozzle after the evacuation needs to be extracted through a long distance with the evacuated nozzle pressed by a pair of seal blocks. 
     In view of the foregoing problem, it is desirable to provide a liquid injection device structured to certainly evacuate gas inside a bag-shaped film exterior. 
     PRIOR ART DOCUMENT(S) 
     Patent Document(s) 
     
         
         Patent Document 1: JP 2012-64468 A 
       
    
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, an inner circumferential nozzle is structured to have a suction port open at a position protuberant with respect to a liquid injection port of an outer circumferential nozzle in an axial direction of the outer circumferential nozzle, in a state that the inner circumferential nozzle is expanded. 
     According to one aspect of the present invention, the inner circumferential nozzle is expanded inside a bag-shaped film exterior. This serves to certainly evacuate gas inside the bag-shaped film exterior. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a liquid injection device according to an embodiment. 
         FIG. 2  is an illustrative view of a bag-shaped laminate film exterior with a nozzle inserted therein. 
         FIG. 3  is a longitudinal sectional view of the nozzle along its axis. 
         FIG. 4  is an illustrative view of the liquid injection device viewed from a front side of  FIG. 1 . 
         FIG. 5  is a perspective view of an elastic body employed in a primary seal mechanism. 
         FIG. 6  is a cross sectional view of the liquid injection device along a line A-A shown in  FIG. 1 . 
         FIG. 7  is a perspective view of an elastic body employed in a secondary seal mechanism. 
         FIG. 8A  is an illustrative view of a process for evacuation in the bag-shaped laminate film exterior. 
         FIG. 8B  is an illustrative view of a process for liquid injection into the bag-shaped laminate film exterior. 
         FIG. 8C  is an illustrative view of a process for seal of the bag-shaped laminate film exterior after the liquid injection. 
     
    
    
     MODE(S) FOR CARRYING OUT THE INVENTION 
     The following describes an embodiment of the present invention, with reference to the drawings. 
       FIG. 1  shows a liquid injection device  2  structured to inject electrolytic solution into a film exterior battery  1 . The film exterior battery  1  is exemplarily a lithium ion secondary battery, and includes a generation element  3 , a bag-shaped laminate film exterior  4 , a cathode tab  5 , and an anode tab  6  (see  FIG. 2 ). The generation element  3  has a rectangle shape, and includes a stack of: a cathode and an anode being electrodes not shown; and a separator not shown which is interposed between the cathode and the anode. The bag-shaped laminate film exterior  4  is structured to contain the generation element  3  together with the electrolytic solution. Each of the cathode tab  5  and the anode tab  6  is connected to the bag-shaped laminate film exterior  4 . 
     The following further describes the bag-shaped laminate film exterior  4  to which liquid injection is implemented. As shown in  FIG. 2 , the bag-shaped laminate film exterior  4  is formed by: superposing two rectangle laminate films to each other such that the cathode tab  5  and the anode tab  6  are led outside respectively from a side  4   a  and a side  4   b  parallel with the side  4   a ; and then heat-welding the side  4   a , the side  4   b , and a side  4   c  respectively. In this state that the sides  4   a ,  4   b , and  4   c  have been respectively heat-welded, an opening  7  for the injection of electrolytic solution is formed at an upper side  4   d . The electrolytic solution is to be injected via the opening  7 , into the bag-shaped laminate film exterior  4  containing the generation element  3 . 
     The liquid injection device  2  includes a presser jig  8 , a nozzle  9 , a primary seal mechanism  10 , a secondary seal mechanism  11 , and a heat seal mechanism  12 . The presser jig  8  is structured to hold the bag-shaped laminate film exterior  4  including the opening  7 . The nozzle  9  is structured to be used in evacuation of the bag-shaped laminate film exterior  4  and in injection of the electrolytic solution into the bag-shaped laminate film exterior  4 . The primary seal mechanism  10  is structured to press the opening  7  of the bag-shaped laminate film exterior  4  from both sides of the bag-shaped laminate film exterior  4 , with the nozzle  9  inserted in the opening  7 . The secondary seal mechanism  11  is structured to seal the opening  7  after the liquid injection of electrolytic solution. The heat seal mechanism  12  is structured to heat-seal the opening  7  after the liquid injection. 
     The presser jig  8  is disposed below the primary seal mechanism  10 , the secondary seal mechanism  11 , and the heat seal mechanism  12 , and is mounted on a presser jig fixing base  13 . The presser jig  8  exemplarily has a cuboid shape, and includes an insertion hole  14  in which the bag-shaped laminate film exterior  4  is inserted in an attitude that the opening  7  opens upward. As shown in  FIG. 1 , in a state that the bag-shaped laminate film exterior  4  is inserted in the insertion hole  14 , the bag-shaped laminate film exterior  4  has an upper part projecting upward from an upper surface  8   a  of the presser jig  8 . The primary seal mechanism  10 , the secondary seal mechanism  11 , and the heat seal mechanism  12  are structured to act on the upper part of the bag-shaped laminate film exterior  4 . 
     The nozzle  9  is structured movable upward and downward, and, as shown in  FIG. 3 , includes an outer circumferential nozzle  15 , an inner circumferential nozzle  16 , and a shaft  17 . The outer circumferential nozzle  15  has a cylindrical tubular shape. The inner circumferential nozzle  16  similarly has a cylindrical tubular shape, and is structured expandable telescopically through the outer circumferential nozzle  15 . The shaft  17  has a cylindrical shape, and is structured expandable telescopically through the inner circumferential nozzle  16 . 
     The outer circumferential nozzle  15 , the inner circumferential nozzle  16 , and the shaft  17  have a common central axis M shown as a dash-dot line in  FIG. 3 . In the following description, a direction of the central axis M is referred to as “axial direction” for convenience of explanation. Furthermore, a lower end side in the axial direction in  FIG. 3  is referred to as “first end side in the axial direction”, and an upper end side in the axial direction in  FIG. 3  is referred to as “second end side in the axial direction”. 
     The outer circumferential nozzle  15  has an inner diameter greater than an outer diameter of the inner circumferential nozzle  16 , so as to form an electrolytic solution passage  19  between the outer circumferential nozzle  15  and the inner circumferential nozzle  16  structured to expand and contract through the outer circumferential nozzle  15 . The electrolytic solution passage  19  has an annular shape, through which the electrolytic solution flows. In a state that the inner circumferential nozzle  16  is expanded, the electrolytic solution passage  19  has an outlet in the first end side in the axial direction, namely, a liquid injection port  20 . The liquid injection port  20  has an annular shape, and is formed between a tip of the outer circumferential nozzle  15  and an outer periphery of the inner circumferential nozzle  16 . The inner circumferential nozzle  16  includes in its tip a diameter expansion portion  24  serving as a valve. Accordingly, the liquid injection port  20  is opened and closed due to relative move between the outer circumferential nozzle  15  and the inner circumferential nozzle  16 . The inner circumferential nozzle  16  includes an electrolytic solution sealing member  26  that has an annular shape and is structured to, in a state that the liquid injection port  20  is closed as shown in  FIG. 3 , fluid-tightly seal a gap between a slope  15   a  of the outer circumferential nozzle  15  and an outer peripheral slope  24   a  of the inner circumferential nozzle  16 . The slope  15   a  is formed in the first end side in the axial direction, as a diameter expansion portion tapered in a conical shape. The outer peripheral slope  24   a  is formed in the diameter expansion portion  24  in the tip of the inner circumferential nozzle  16 . The electrolytic solution sealing member  26  is made of elastic material such as rubber, and is disposed in an annular groove formed in the outer peripheral slope  24   a.    
     The electrolytic solution passage  19  extends from the liquid injection port  20  to the second end side in the axial direction, so as to communicate with an electrolytic solution supply passage  21 . The electrolytic solution supply passage  21  is defined by a projection  15   c  having a tubular shape projecting from an outer periphery of the outer circumferential nozzle  15 . The electrolytic solution supply passage  21  is connected to a liquid injection pump  22  serving as a supply source of the electrolytic solution. 
     The outer circumferential nozzle  15  includes two annular grooves  15   d  formed in an inner periphery of the outer circumferential nozzle  15 , in the second end side in the axial direction. Each of the annular grooves  15   d  contains a seal member  23  having an annular shape. The seal member  23  is made of elastic material such as rubber, and is structured to liquid-tightly seal a gap between the inner periphery of the outer circumferential nozzle  15  and the outer periphery of the inner circumferential nozzle  16  while securing sliding contact therebetween. 
     The outer circumferential nozzle  15  further includes an overhang  15   b  in the second end side in the axial direction. The overhang  15   b  overhangs outward from the outer periphery of the outer circumferential nozzle  15 , perpendicularly to the axial direction. The overhang  15   b  is structured to receive a pressing force from a rod  18   a  of a hydraulic actuator  18 . The hydraulic actuator  18  is a linear reciprocation actuator connected to a hydraulic pump not shown. The pressing force from the hydraulic actuator  18  is exerted from the second end side in the axial direction, and causes the outer circumferential nozzle  15  to move downward together with the inner circumferential nozzle  16  and the shaft  17 . 
     The inner circumferential nozzle  16  has the cylindrical tubular shape longer than the outer circumferential nozzle  15 . The inner circumferential nozzle  16  has an inner diameter greater than an outer diameter of the shaft  17 , so as to form a decompression passage  28  between the inner circumferential nozzle  16  and the shaft  17  structured to expand and contract through the inner circumferential nozzle  16 . The decompression passage  28  has an annular shape, through which gas flows during evacuation for producing a vacuum. In a state that the shaft  17  is expanded, the decompression passage  28  has an inlet in the first end side in the axial direction, namely, a suction port  29 . The suction port  29  has an annular shape, and is formed between the tip of the inner circumferential nozzle  16  and an outer periphery of the shaft  17 . The shaft  17  includes in its tip a valve  25  having a truncated conical shape. Accordingly, the suction port  29  is opened and closed due to relative move between the inner circumferential nozzle  16  and the shaft  17 . The shaft  17  includes a gas sealing member  33  that has an annular shape and is structured to, in a state that the suction port  29  is closed as shown in  FIG. 3 , gas-tightly seal a gap between an inner peripheral slope  24   b  of the inner circumferential nozzle  16  and a tapered surface  25   a  of the shaft  17 . The inner peripheral slope  24   b  is formed in the diameter expansion portion  24  of the inner circumferential nozzle  16 . The tapered surface  25   a  is formed in the valve  25  in the tip of the shaft  17 . The gas sealing member  33  is made of rubber similarly to the electrolytic solution sealing member  26 , and is disposed in an annular groove formed in the valve  25 . 
     The decompression passage  28  extends from the suction port  29  to the second end side in the axial direction, so as to be longer than the electrolytic solution passage  19 . The decompression passage  28  communicates with a gas discharging passage  30  defined by a projection  16  having a tubular shape projecting from the outer periphery of the inner circumferential nozzle  16 . The gas discharging passage  30  is connected to a vacuum pump  31 . 
     Similarly to the outer circumferential nozzle  15 , the inner circumferential nozzle  16  includes two annular grooves  16   c  formed in an inner periphery of the inner circumferential nozzle  16 , in the second end side in the axial direction. Each of the annular grooves  16   c  contains a seal member  32  having an annular shape. The seal member  32  is made of elastic material such as rubber, and is structured to gas-tightly seal a gap between the inner periphery of the inner circumferential nozzle  16  and the outer periphery of the shaft  17  so as to suppress an atmosphere from intruding into the decompression passage  28 , while securing sliding contact between the inner circumferential nozzle  16  and the shaft  17 . 
     The inner circumferential nozzle  16  further includes an overhang  16   a  in the second end side in the axial direction. The overhang  16   a  overhangs outward in the same direction with the overhang  15   b  of the outer circumferential nozzle  15 . The overhang  16   a  is connected to a rod  27   a  of a hydraulic actuator  27  that is a linear reciprocation actuator supported by the overhang  15   b . The rod  27   a  of the hydraulic actuator  27  is driven to cause the inner circumferential nozzle  16  to move in the axial direction, relatively with respect to the outer circumferential nozzle  15 . 
     The shaft  17  has the cylindrical shape longer than the inner circumferential nozzle  16 . The shaft  17  includes an overhang  17   a  formed similarly to the overhang  15   b  and the overhang  16   a , in the second end side in the axial direction. The overhang  17   a  is connected to a rod  34   a  of a hydraulic actuator  34  that is a linear reciprocation actuator supported by the overhang  16   a . The rod  34   a  of the hydraulic actuator  34  is driven to cause the shaft  17  to move in the axial direction, relatively with respect to the inner circumferential nozzle  16 . 
     The primary seal mechanism  10  is disposed below the heat seal mechanism  12  as shown in  FIG. 1 , and is structured to establish sealing around the outer circumferential nozzle  15  by pressing the both sides of the bag-shaped laminate film exterior  4  in which the nozzle  9  is inserted. The primary seal mechanism  10  includes a pair of elastic bodies  35  and  36  structured to establish the sealing around the outer circumferential nozzle  15 , and includes a pair of holders  37  and  38  structured to respectively hold the pair of elastic bodies  35  and  36 . 
     As shown in  FIG. 4 , the elastic body  35  is disposed in a first side with respect to the bag-shaped laminate film exterior  4  (i.e. a right side in  FIG. 4 ), and is structured to establish the sealing around the outer circumferential nozzle  15  along a seal line L 1  (see  FIG. 2 ) crossing the nozzle  9 , by pressing the opening  7  together with the nozzle  9  from the both sides of the bag-shaped laminate film exterior  4  in cooperation with the elastic body  36 . The elastic body  35  is made of rubber being elastic material, such as fluoro rubber. The elastic body  35  has a shape of slender rod with a circular cross section, and has a length enough to seal the opening  7  at the upper side  4   d  of the bag-shaped laminate film exterior  4 . As shown in  FIG. 5 , the elastic body  35  includes at its center a curve portion  39  having a semicircular shape curving to fit with the outer periphery of the outer circumferential nozzle  15  of the nozzle  9 . As shown in  FIG. 6 , the curve portion  39  has a size to appropriately press the outer circumferential nozzle  15  and a part of the bag-shaped laminate film exterior  4  around the outer circumferential nozzle  15 , upon pressing the opening  7  together with the outer circumferential nozzle  15  from outside of the bag-shaped laminate film exterior  4 . 
     The holder  37  is exemplarily made of metal, and has a substantially U-shaped cross section as shown in  FIG. 4 . The holder  37  includes a bottom wall  37   a  rising vertically, and a pair of side walls  37   b ,  37   b  extending horizontally from the bottom wall  37   a , parallel with each other. The bottom wall  37   a  and the pair of side walls  37   b ,  37   b  define a recessed groove  37   c  formed to contain the elastic body  35 . The elastic body  35  is heat-welded or glued to the holder  37 . In addition, each of the pair of side walls  37   b ,  37   b  includes a cut-out portion  37   d  shaped in conformance with the curve portion  39  of the elastic body  35  as shown in  FIG. 6 , so as to avoid interference with the outer circumferential nozzle  15 . 
     As shown in in  FIG. 4 , the elastic body  36  is disposed in a second side with respect to the bag-shaped laminate film exterior  4  (i.e. a left side in  FIG. 4 ). The elastic body  36  is made of rubber harder than that for the elastic body  35 , such as silicone rubber, and has a shape of flat sheet. 
     The holder  38  is exemplarily made of metal, and has a cuboid shape as shown in  FIG. 4  onto which the elastic body  36  is heat-welded or glued. 
     As shown in  FIG. 1 , the primary seal mechanism  10  is disposed along the seal line L 1  shown in  FIG. 2 , and includes hydraulic actuators  40  and  50 . The hydraulic actuators  40  and  50  are structured to cause the elastic bodies  35  and  36  to linearly reciprocate independently of each other, with respect to the bag-shaped laminate film exterior  4 . As shown in  FIG. 4 , the hydraulic actuator  40  includes a rod  40   a  connected to the bottom wall  37   a  of the holder  37 , and the hydraulic actuator  50  includes a rod  50   a  connected to the holder  38 . The hydraulic actuators  40  and  50  are structured to work in coordination with each other so as to open and close the elastic bodies  35  and  36  disposed opposite to each other across the opening  7 . 
     The primary seal mechanism  10  corresponds to a first seal mechanism in the claims. 
     The secondary seal mechanism  11  is disposed nearer to the generation element  3  than the primary seal mechanism  10 , namely along the seal line L 2  shown in  FIG. 2 . The secondary seal mechanism  11  is structured to prevent leakage of the electrolytic solution and intrusion of the atmosphere, by sealing the opening  7  without interposing the nozzle  9  after a process for the liquid injection. The secondary seal mechanism  11  includes a pair of elastic bodies  41  and  42  and a pair of holders  43  and  44  structured to hold the pair of elastic bodies  41  and  42 . 
     As shown in  FIG. 4 , the elastic body  41  is disposed in the first side with respect to the bag-shaped laminate film exterior  4  (i.e. the right side in  FIG. 4 ) and below the elastic body  35 , and is structured to seal the opening  7  along the seal line L 2  (see  FIG. 2 ) by pressing the opening  7  from the both sides of the bag-shaped laminate film exterior  4  in cooperation with the elastic body  42 . The elastic body  41  is made of rubber same with the elastic body  35 , such as the fluoro rubber, and has a hardness same with the elastic body  35 . As shown in  FIG. 7 , the elastic body  41  has a slender cylindrical shape, and has a length enough to seal the opening  7  at the upper side  4   d  of the bag-shaped laminate film exterior  4 , similarly to the elastic body  35 . 
     The holder  43  is exemplarily made of metal, and, as shown in  FIG. 4 , has a substantially U-shaped cross section. The holder  43  is configured similarly to the holder  37 , and includes a bottom wall  43   a , a pair of side walls  43   b ,  43   b , and a recessed groove  43   c  defined by the bottom wall  43   a  and the pair of side walls  43   b ,  43   b . The recessed groove  43   c  contains the elastic body  41  that is heat-welded or glued to the recessed groove  43   c.    
     The elastic body  42  is made of rubber same with the elastic body  36 , and has a shape of flat sheet. 
     The holder  44  has a cuboid shape similar to the holder  38 , onto which the elastic body  42  is heat-welded or glued. 
     As shown in  FIG. 1 , the secondary seal mechanism  11  includes hydraulic actuators  45  and  51 . The hydraulic actuators  45  and  51  respectively include rods  45   a  and  51   a  (see  FIG. 4 ) structured to open and close the elastic bodies  41  and  42  disposed opposite to each other across the opening  7 . 
     The secondary seal mechanism  11  corresponds to a second seal mechanism in the claims. 
     The heat seal mechanism  12  includes a pair of seal heaters  46 ,  46  structured to heat-seal the opening  7  of the bag-shaped laminate film exterior  4  after the injection of electrolytic solution. The pair of seal heaters  46 ,  46  are configured substantially same with each other, and are disposed above the primary seal mechanism  10  as shown in  FIG. 1 . For example, each of the pair of seal heaters  46 ,  46  has a block-like shape, and is made of metal sufficient in thermal conductivity, and internally includes a heat source such as a hot wire. Furthermore, each of the pair of seal heaters  46 ,  46  is connected to an actuator not shown, in order to open and close interposing the opening  7 . 
     Upon use of thus-configured liquid injection device  2 , the tip of the nozzle  9  is caused to move downward due to action of the hydraulic actuator  18  and is inserted into the opening  7 , with the bag-shaped laminate film exterior  4  inserted in the insertion hole  14  in the attitude that the opening  7  opens upward as shown in  FIG. 1 . Then, the pair of elastic bodies  35  and  36  are caused to approach each other due to action of the hydraulic actuators  40  and  50 , so as to press from the both sides the bag-shaped laminate film exterior  4  in which the nozzle  9  is inserted. Thus, the elastic bodies  35  and  36  establish the sealing around the outer circumferential nozzle  15  together with the bag-shaped laminate film exterior  4 . 
     Next, the following describes an evacuation process, a liquid injection process, and a seal process of the bag-shaped laminate film exterior  4 , with reference to  FIGS. 8A, 8B, and 8C . 
     In  FIGS. 8A, 8B, and 8C , the nozzle  9  is already inserted in the bag-shaped laminate film exterior  4 . Each broken line in the drawings represents the pair of elastic bodies  35  and  36  pressing the bag-shaped laminate film exterior  4  from the both sides at a position of the seal line L 1  (see  FIG. 2 ) with the outer circumferential nozzle  15  inserted in the bag-shaped laminate film exterior  4 . In  FIG. 8C , a dash-dot line represents the pair of elastic bodies  41  and  42  sealing the bag-shaped laminate film exterior  4  at a position of the seal line L 2  (see  FIG. 2 ). 
     As shown in  FIG. 8A , in the evacuation process, the inner circumferential nozzle  16  is caused to project to the first end side in the axial direction with respect to the outer circumferential nozzle  15 , due to action of the hydraulic actuator  27 . After the inner circumferential nozzle  16  has projected, as shown in  FIG. 8A , the annular liquid injection port  20  between the tip of the outer circumferential nozzle  15  and the outer periphery of the inner circumferential nozzle  16  is open. Furthermore, the diameter expansion portion  24  of the inner circumferential nozzle  16  is at a position protuberant to the first end side in the axial direction with respect to the liquid injection port  20 . 
     Then, while maintaining the diameter expansion portion  24  protuberant to the first end side in the axial direction, the shaft  17  is caused to project to the first end side in the axial direction with respect to the inner circumferential nozzle  16 . After the shaft  17  has projected, the annular suction port  29  between the diameter expansion portion  24  and the outer periphery of the  17  is open. Furthermore, the valve  25  is at a position protuberant to the first end side in the axial direction with respect to the diameter expansion portion  24 . Thus, the suction port  29  at the tip of the inner circumferential nozzle  16  opens in the bag-shaped laminate film exterior  4 , at a position protuberant to the first end side in the axial direction with respect to the liquid injection port  20  of the outer circumferential nozzle  15 . In addition, the valve  25  at the protuberant position is in a vicinity of an edge of the generation element  3 . 
     Next, as shown by arrows G in  FIG. 8A , the vacuum pump  31  evacuates gas inside the bag-shaped laminate film exterior  4 , i.e. produces a vacuum in the bag-shaped laminate film exterior  4 , through the suction port  29  and the decompression passage  28 . 
     As shown in  FIG. 8B , in the liquid injection process subsequent to the evacuation process, the shaft  17  is retracted upward with respect to the inner circumferential nozzle  16 , due to action of the hydraulic actuator  34 . Thus, as shown in  FIG. 8B , the suction port  29  of the inner circumferential nozzle  16  is closed from outside by the valve  25 , and the gap between the tapered surface  25   a  and the inner peripheral slope  24   b  is gas-tightly sealed by the gas sealing member  33 . 
     Then, as shown by arrows L in  FIG. 8B , the electrolytic solution is injected into the bag-shaped laminate film exterior  4  through the electrolytic solution passage  19  and the liquid injection port  20 , by operating the liquid injection pump  22  with the suction port  29  closed by the valve  25 . 
     As shown in  FIG. 8C , in the seal process subsequent to the liquid injection process, the inner circumferential nozzle  16  is retracted upward together with the shaft  17  from the axial position shown in  FIG. 8B , due to action of the hydraulic actuator  27 . The retraction of the inner circumferential nozzle  16  causes the liquid injection port  20  of the outer circumferential nozzle  15  to be closed by the diameter expansion portion  24  of the inner circumferential nozzle  16  as shown in  FIG. 8C , and causes the gap between the slope  15   a  and the outer peripheral slope  24   a  to be liquid-tightly sealed by the electrolytic solution sealing member  26 . 
     Then, with the liquid injection port  20  and the suction port  29  closed, the opening  7  of the bag-shaped laminate film exterior  4  is sealed at the position of the seal line L 2  by the pair of elastic bodies  41  and  42 . 
     Next, while maintaining the pair of elastic bodies  41  and  42  sealing the opening  7  of the bag-shaped laminate film exterior  4 , the pair of elastic bodies  35  and  36  are retracted away from the bag-shaped laminate film exterior  4 , and subsequently the nozzle  9  is extracted from the opening  7 . 
     Subsequently to the seal process shown in  FIG. 8C , a heat seal process is implemented to heat the bag-shaped laminate film exterior  4  from the both sides at a position above the seal line L 1  shown in  FIG. 2 , by the pair of seal heaters  46 ,  46 . This causes the bag-shaped laminate film exterior  4  to be heat-sealed along the upper side  4   d  shown in  FIG. 2 . 
     As described above, the present embodiment is configured such that during the evacuation in the bag-shaped laminate film exterior  4 , the suction port  29  in the tip of the inner circumferential nozzle  16  is open inside the bag-shaped laminate film exterior  4 , at the position protuberant in the axial direction with respect to the liquid injection port  20  of the outer circumferential nozzle  15 . In other words, the inner circumferential nozzle  16  is inserted in the bag-shaped laminate film exterior  4  deeply to reach the vicinity of the generation element  3  such that the suction port  29  is positioned in the vicinity of the edge of the generation element  3 . Since upon the evacuation the inner circumferential nozzle  16  is expanded inside of the bag-shaped laminate film exterior  4  such that the suction port  29  is positioned in the vicinity of the edge of the generation element  3 , the evacuation in the bag-shaped laminate film exterior  4  is certainly performed via the suction port  29 . 
     If a nozzle is formed as a single pipe and is deeply inserted into a bag-shaped laminate film exterior upon evacuation, the bag-shaped laminate film exterior may be deteriorate in sealability because the nozzle needs to be extracted through a long distance after the evacuation. 
     In contrast, according to the present embodiment, the outer circumferential nozzle  15 , around which the seal is established by the elastic bodies  35  and  36 , does not need to be deeply inserted into the bag-shaped laminate film exterior  4 . This serves to suppress the bag-shaped laminate film exterior  4  from deteriorating in sealability due to the retraction of the nozzle  9 . 
     Moreover, according to the present embodiment, the suction port  29  of the inner circumferential nozzle  16  is opened and closed by the valve  25  disposed in the tip of the shaft  17 , wherein the suction port  29  is closed by the valve  25  during the liquid injection. This serves to certainly insulate the decompression passage  28  from the electrolytic solution passage  19  during the liquid injection. 
     Furthermore, according to the present embodiment, the liquid injection device  2  includes two seal mechanisms: the primary seal mechanism  10  and the secondary seal mechanism  11 . After the evacuation, the nozzle  9  is extracted from the opening  7  of the bag-shaped laminate film exterior  4  subsequently to release of the seal of the pair of elastic bodies  35  and  36  while maintaining the pair of elastic bodies  41  and  42  sealing the opening  7 . This serves to secure the bag-shaped laminate film exterior  4  in sealability by the pair of elastic bodies  41  and  42 , and thereby suppress the bag-shaped laminate film exterior  4  from deteriorating in sealability due to the extraction of the nozzle  9 . 
     Furthermore, according to the present embodiment, the elastic bodies  35  and  36  are configured to establish sealing around only one nozzle, i.e. around the outer circumferential nozzle  15 . This serves to facilitate extracting the outer circumferential nozzle  15  in comparison with a case of extracting one liquid injection nozzle and one evacuation nozzle around which sealing is established by a pair of elastic bodies. 
     In addition, although the above embodiment exemplarily employs the bag-shaped laminate film exterior  4  formed by superposing two rectangle laminate films to each other and then respectively heat-welding three sides thereof, the present invention may alternatively employ a bag-shaped film exterior formed by folding one rectangle laminate film in two and then respectively heat-welding two sides perpendicular to a folded side of the bag-shaped film exterior. 
     Moreover, although the above embodiment exemplarily employs the film exterior battery  1  structured such that the cathode tab  5  is led outside from the side  4   a  of the bag-shaped laminate film exterior  4  and the anode tab  6  is led outside from the side  4   b  of the bag-shaped laminate film exterior  4 , the present invention may be applied in order to alternatively employ a film exterior battery  1  structured such that the cathode tab  5  and the anode tab  6  are led outside from a common one side. 
     Furthermore, although the above embodiment is exemplarily configured to dispose the bag-shaped laminate film exterior  4  in the attitude that the opening  7  of the bag-shaped laminate film exterior  4  opens upward, the bag-shaped laminate film exterior  4  may be disposed in another attitude. 
     DESCRIPTION OF THE SIGNS 
     
         
         
           
               2  . . . liquid injection device 
               4  . . . bag-shaped laminate film exterior 
               9  . . . nozzle 
               10  . . . primary seal mechanism 
               11  . . . secondary seal mechanism 
               15  . . . outer circumferential nozzle 
               16  . . . inner circumferential nozzle 
               17  . . . shaft 
               19  . . . electrolytic solution passage 
               20  . . . liquid injection port 
               25  . . . valve 
               28  . . . decompression passage 
               29  . . . suction port