JP5605115B2 - Electrolytic solution pouring method and electrolytic solution pouring device - Google Patents

Description

  The present invention relates to an electrolytic solution injection method and an electrolytic solution injection device in battery manufacture.

  In manufacturing a battery such as a lithium ion secondary battery, generally, a power generation element including an electrode or the like is accommodated in an exterior material, and an electrolytic solution is injected into the exterior material. In recent years, attempts have been made to reduce the penetration time of the electrolytic solution into the power generation element. For example, the invention described in Patent Document 1 attempts to reduce the penetration time by reducing the pressure inside the exterior material and pressurizing the electrolytic solution.

JP 09-199108 A

  However, in the above prior art, since the electrolyte is discharged from the tip of the hollow needle inserted into the exterior material toward the power generation element, the electrolyte penetrates from the upper side of the power generation element where the tip of the hollow needle is located. It was only. That is, in the prior art, the electrolyte solution hardly permeates from a place other than the upper side of the power generation element, and the electrolyte solution permeation path is limited. For this reason, there has been room for improvement in reducing the permeation time of the electrolyte.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an electrolytic solution pouring method and an electrolytic solution pouring device that can further reduce the permeation time.

In order to achieve the above object, the method for injecting an electrolytic solution of the present invention includes an injecting means inserting step of inserting an injecting means for discharging the electrolytic solution into an exterior material containing a chargeable / dischargeable power generation element ; And an electrolyte injection step of injecting an electrolyte from the injection means into the exterior material after the injection means insertion step. The electrolytic solution injection step is characterized in that the electrolytic solution is injected in a state in which a liquid injection port provided on the cylindrical outer peripheral wall of the liquid injection means is directed in a direction different from the direction toward the power generation element . In addition, the method for injecting an electrolytic solution of the present invention includes a sealing step for sealing the exterior material after the injection means insertion step and before the electrolytic solution injection step, and the sealing step includes opening the exterior material in the injection means. In the state inserted in the part, the exterior material is pressed by an elastic jig to seal the opening.

  In the present invention, the electrolytic solution is injected into the exterior material from the injection port provided on the outer peripheral wall of the liquid injection means, so that most of the electrolytic solution travels through the exterior material and is opposite to the upper side of the power generation element. Stay on the side. Then, the staying electrolytic solution penetrates into the power generation element by capillary action. In addition, a part of the electrolytic solution hits the exterior material and bounces back and soaks in from the upper side of the power generation element. Therefore, the path of the electrolytic solution is dispersed and the time until the electrolyte penetrates is shortened.

It is a schematic block diagram which shows the liquid injection apparatus which concerns on embodiment. It is a principal part enlarged view of the nozzle which concerns on embodiment. It is a top view of the battery concerning an embodiment. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. It is a flowchart which shows the liquid injection method which concerns on embodiment. It is a principal part enlarged view of the liquid injection apparatus which concerns on embodiment. It is a top view which shows typically the penetration path | route of the electrolyte solution in a comparative example. It is a top view which shows typically the penetration path | route of the electrolyte solution in embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio.

  As shown in FIG. 1, an electrolyte solution injection device 100 according to the present embodiment guides the movement of a holding jig 110 that holds an unsealed battery 10 that is an injection target of the electrolytic solution, and the holding jig 110. And a guide rail 115. The liquid injection device 100 includes a liquid injection nozzle 120 (liquid injection means) that discharges the electrolytic solution, and a nozzle lifting unit 102 that moves the nozzle 120 up and down.

  In addition, the liquid injection device 100 includes a seal block 104 (an elastic jig) for sealing the opening 16 of the battery 10 in which the nozzle 120 is inserted, and the opening 16 of the battery 10 after the electrolyte is injected. And a sealing heater 103 for heat sealing. The liquid injection device 100 also includes a control unit 101 that controls operations of the nozzle 120, the seal block 104, and the sealing heater 103.

  The holding jig 110 has a rectangular parallelepiped shape, and has a hole 111 into the battery 10 on the upper surface. The battery 10 has a flat shape, and the operator sets the battery 10 so that the opening 16 faces upward and the battery 10 is inserted into the hole 111.

  The holding jig 110 is placed on a plate-like weight measuring device 113 via a plate-like holding jig fixing base 112. The holding jig fixing base 112 fixes the holding jig 110 on the weight measuring device 113.

  The weight measuring device 113 is placed on a holding jig loading table 114 that moves along the guide rail 115. The holding jig 110 moves on the guide rail 115 together with the holding jig loading table 114. The guide rail 115 extends between an electrolyte solution injection position below the nozzle 120 and a battery set position spaced apart from the electrolyte solution injection position. The operator sets the battery 10 on the holding jig 110 at the battery setting position.

  The seal block 104 is disposed so as to sandwich the battery 10 that has moved to the electrolyte injection position from the thickness direction. The seal block 104 is connected to a drive unit 106 including, for example, a motor, a hydraulic cylinder, and the like. The seal block 104 is moved close to and away from the battery 10 by the driving unit 106. The clamping force when pressing with the battery 10 in between can be arbitrarily set.

  The seal block 104 is formed of an elastic body. The material constituting the seal block 104 is, for example, silicone rubber. The hardness of the silicone rubber is preferably A10 (conforming to JIS K 253 type A). The seal block 104 has a rectangular parallelepiped shape, and its size is, for example, 80 mm × 10 mm × 50 mm.

  The sealing heater 103 is positioned on the seal block 104 and is disposed so as to sandwich the battery 10 that has moved to the electrolyte injection position from the thickness direction. The sealing heater 103 is connected to a driving unit 105 including, for example, a motor, a hydraulic cylinder, and the like. The sealing heater 103 is moved close to and away from the battery 10 by the driving unit 105. The clamping force when pressing with the battery 10 in between can be arbitrarily set. The sealing heater 103 has a block shape, and is formed of, for example, a metal material having excellent thermal conductivity. In addition, the sealing heater 103 includes a heating element such as a heat ray inside.

  The nozzle lifting / lowering unit 102 includes, for example, a motor, a hydraulic cylinder, and the like, and moves the nozzle 120 close to and away from the battery 10 that has moved to the electrolyte injection position by these driving forces.

  The control unit 101 is electrically connected to the drive unit 106. The control unit 101 controls the approach and separation operation of the seal block 104 with respect to the battery 10 and the clamping force when the battery 10 is pressed while being sandwiched. Further, the control unit 101 is electrically connected to the driving unit 105 and the heating element in the sealing heater 103. The control unit 101 controls the approach and separation operation of the sealing heater 103 with respect to the battery 10 and the temperature rise of the sealing heater 103. The control unit 101 is electrically connected to the nozzle lifting / lowering unit 102 and controls the lifting / lowering operation of the nozzle 120 with respect to the battery 10. The control unit 101 includes a CPU and a memory as main components.

  As shown in FIG. 2, the nozzle 120 has a liquid injection port 121 for discharging an electrolytic solution in a cylindrical outer peripheral wall 123. The nozzle 120 has a plurality of liquid injection ports 121 on the entire circumference of the outer peripheral wall 123. The nozzle 120 communicates with a tank (not shown) that stores the electrolyte and a pump (not shown) that pressurizes the electrolyte. The control unit 101 is electrically connected to the pump and controls discharge of the electrolytic solution from the nozzle 120.

  As shown in FIGS. 3 and 4, the battery 10 includes a power generation element 21 that can be charged and discharged, and a laminate sheet 29 (exterior material) that houses the power generation element 21. The battery 10 of the present embodiment is a stacked secondary battery.

  The power generation element 21 includes a positive electrode in which the positive electrode active material layer 13 is disposed on both surfaces of the positive electrode current collector 11, an electrolyte layer 17, and a negative electrode in which the negative electrode active material layer 15 is disposed on both surfaces of the negative electrode current collector 12. It has a stacked configuration. Specifically, the negative electrode, the electrolyte layer, and the positive electrode are laminated in this order so that one positive electrode active material layer 13 and the negative electrode active material layer 15 adjacent thereto face each other with the electrolyte layer 17 therebetween. .

  As a result, the adjacent positive electrode, electrolyte layer, and negative electrode constitute one unit cell layer 19. Therefore, it can be said that the battery 10 has a configuration in which a plurality of single battery layers 19 are stacked and electrically connected in parallel. In addition, although the positive electrode active material layer 13 is arrange | positioned only at one side in the outermost layer positive electrode collector located in both outermost layers of the electric power generation element 21, an active material layer may be provided in both surfaces. That is, instead of using a current collector dedicated to the outermost layer provided with an active material layer only on one side, a current collector having an active material layer on both sides may be used as it is as an outermost current collector. In addition, the arrangement of the positive electrode and the negative electrode is reversed from that in FIG. 4 so that the outermost negative electrode current collector is positioned in both outermost layers of the power generation element 21, and the outermost negative electrode current collector is disposed on one or both surfaces. A negative electrode active material layer may be disposed.

  The positive electrode current collector 11 and the negative electrode current collector 12 are attached to a positive electrode current collector plate 25 and a negative electrode current collector plate 27 that are electrically connected to the respective electrodes (positive electrode and negative electrode), and are sandwiched between edges of the laminate sheet 29. Thus, it has a structure led out of the laminate sheet 29. The positive electrode current collector plate 25 and the negative electrode current collector plate 27 are ultrasonically welded to the positive electrode current collector 11 and the negative electrode current collector 12 of each electrode through a positive electrode lead and a negative electrode lead (not shown), respectively, as necessary. Or resistance welding or the like.

  Hereinafter, each component of the battery 10 will be described by taking a laminated lithium ion secondary battery as an example.

The positive electrode active material layer 13 includes a positive electrode active material. The positive electrode active material has a composition that occludes ions during discharging and releases ions during charging. A preferable example is a lithium-transition metal composite oxide that is a composite oxide of a transition metal and lithium. Specifically, Li · Co-based composite oxide such as LiCoO _2, Li · Ni-based composite oxide such as LiNiO _2, Li · Mn-based composite oxide such as spinel LiMn ₂ O _4, Li · such LiFeO ₂ Fe-based composite oxides and those obtained by replacing some of these transition metals with other elements can be used. In addition, examples of the positive electrode active material include transition metal oxides such as LiFePO ₄ and lithium phosphate compounds and sulfuric acid compounds; transition metal oxides such as V ₂ O ₅ , MnO ₂ , TiS ₂ , MoS ₂ , and MoO ₃ , and sulfides. Materials; PbO ₂ , AgO, NiOOH, etc. can also be used. As the positive electrode active material, one type may be used alone, or two or more types may be used in combination.

The negative electrode active material layer 15 includes a negative electrode active material. The negative electrode active material has a composition capable of releasing ions during discharge and storing ions during charging. The negative electrode active material is not particularly limited as long as it can reversibly occlude and release lithium. Examples of the negative electrode active material include metals such as Si and Sn, TiO, Ti ₂ O ₃ , TiO ₂ , or Metal oxides such as SiO ₂ , SiO, SnO ₂ , complex oxides of lithium and transition metals such as Li _4/3 Ti _5/3 O ₄ or Li ₇ MnN, Li—Pb alloys, Li—Al alloys , Li, or carbon materials such as natural graphite, artificial graphite, carbon black, activated carbon, carbon fiber, coke, soft carbon, or hard carbon.

  The active material layer may contain other materials if necessary. For example, a conductive aid, a binder, and the like can be included. When an ion conductive polymer is included, a polymerization initiator for polymerizing the polymer may be included.

  A conductive support agent means the additive mix | blended in order to improve the electroconductivity of an active material layer. Examples of the conductive aid include carbon powders such as acetylene black, carbon black, ketjen black, and graphite, various carbon fibers such as vapor grown carbon fiber (VGCF; registered trademark), expanded graphite, and the like. However, it goes without saying that the conductive aid is not limited to these.

  Examples of the binder include polyvinylidene fluoride (PVDF), polyimide, PTFE, SBR, and a synthetic rubber binder. However, it goes without saying that the binder is not limited to these. When the binder and the matrix polymer used as the gel electrolyte are the same, it is not necessary to use a binder.

  The compounding ratio of the components contained in the active material layer is not particularly limited. The blending ratio can be adjusted by appropriately referring to known knowledge about lithium ion secondary batteries. The thickness of the active material layer is not particularly limited, and conventionally known knowledge about the lithium ion secondary battery can be appropriately referred to. As an example, the thickness of the active material layer is preferably about 10 to 100 μm, and more preferably 20 to 50 μm. If the active material layer is about 10 μm or more, the battery capacity can be sufficiently secured. On the other hand, when the active material layer is about 100 μm or less, it is possible to suppress the occurrence of the problem of an increase in internal resistance due to the difficulty in diffusing lithium ions in the electrode deep part (current collector side).

  The positive electrode current collector 11 and the negative electrode current collector 12 are made of a conductive material. The material constituting the positive electrode current collector 11 and the negative electrode current collector 12 is, for example, a metal material such as aluminum, nickel, iron, stainless steel, titanium, or copper, or a conductive material such as polyaniline, polypyrrole, polythiophene, polyacetylene, or polyparaphenylene. Functional polymer material.

  The electrolyte layer 17 has a function as a medium when lithium ions move between the electrodes. The electrolyte layer 17 has a configuration in which a separator as a base material holds an electrolyte. As the electrolyte, for example, a liquid electrolyte made of an electrolytic solution and a polymer electrolyte such as a polymer gel electrolyte can be used as appropriate.

  The electrolytic solution is a solution in which a lithium salt as a supporting salt is dissolved in a solvent. The solvent includes, for example, a carbonate solvent. Here, the “carbonate solvent” means a solvent having a carbonate (O—CO—O) structure in the molecule. Specific examples of carbonate solvents include dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), ethyl methyl carbonate (EMC), methyl propyl carbonate (MPC), and ethyl propyl carbonate (EPC). , Ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), and the like.

  Moreover, the said solvent can further contain other solvents other than a carbonate type solvent. Other solvents include, for example, methyl propionate (MP), methyl acetate (MA), methyl formate (MF), 4-methyldioxolane (4MeDOL), dioxolane (DOL), 2-methyltetrahydrofuran (2MeTHF), tetrahydrofuran ( THF), dimethoxyethane (DME), and γ-butyrolactone (GBL).

As the supporting salt (lithium salt) is not particularly _{limited, LiPF 6, LiBF 4, LiClO} 4, LiAsF 6, LiTaF 6, LiSbF 6, LiAlCl 4, Li 2 B 10 Cl 10, LiI, LiBr, LiCl Inorganic acid anion salts such as LiAlCl, LiHF ₂ , LiSCN, LiCF ₃ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N, LiBOB (lithium bisoxide borate), LiBETI (lithium bis (perfluoroethylenesulfonylimide); And organic acid anion salts such as Li (C ₂ F ₅ SO ₂ ) ₂ N). As for these electrolyte salts, only 1 type may be used independently and 2 or more types may be used together.

  A polymer gel electrolyte, which is a polymer electrolyte, has a configuration in which the above electrolytic solution is injected into a matrix polymer having lithium ion conductivity. Examples of the matrix polymer having lithium ion conductivity include a polymer having polyethylene oxide in the main chain or side chain (PEO), a polymer having polypropylene oxide in the main chain or side chain (PPO), polyethylene glycol (PEG), poly Acrylonitrile (PAN), polymethacrylic acid ester, polyvinylidene fluoride (PVDF), copolymer of polyvinylidene fluoride and hexafluoropropylene (PVDF-HFP), polyacrylonitrile (PAN), poly (methyl acrylate) (PMA), poly (Methyl methacrylate) (PMMA) etc. are mentioned. In addition, mixtures of the above-described polymers, modified products, derivatives, random copolymers, alternating copolymers, graft copolymers, block copolymers, and the like can also be used. Of these, PEO, PPO and their copolymers, PVDF, PVDF-HFP are preferably used. In such a matrix polymer, an electrolyte salt such as a lithium salt can be well dissolved. Further, the matrix polymer can exhibit excellent mechanical strength by forming a crosslinked structure.

  Examples of the separator include microporous membranes made of polyolefins such as polyethylene and polypropylene, hydrocarbons such as polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), glass fibers, and the like.

  The laminate sheet 29 is a flexible bag-like case. The laminate sheet 29 is formed in a bag shape by joining the edges of two superposed sheet-like pieces. The laminate sheet 29 has a substantially rectangular shape (see FIG. 3), and the opening 16 is formed by unsealing an edge portion along one side thereof.

  The material constituting the laminate sheet 29 is, for example, a composite of a polymer and a metal, and has a layer structure in which polypropylene, aluminum, and nylon are laminated in this order. However, the material which comprises the laminate sheet 29 is not restricted to this, A conventionally well-known material may be used.

  Next, a method for injecting the electrolytic solution of this embodiment shown in FIG. 5 will be described.

  In the electrolytic solution pouring method of the present embodiment, first, the operator moves the battery 10 from the battery set position to the electrolytic solution injection position (step S101). At this time, the operator manually moves the holding jig 110 on which the battery 10 is set along the guide rail 115.

  Next, the nozzle raising / lowering unit 102 lowers the nozzle 120 and inserts the nozzle 120 into the laminate sheet 29 through the opening 16 (step S102, liquid injection means insertion step). The liquid injection device 100 also has a vacuuming nozzle (not shown) communicated with a vacuum pump, and the vacuuming nozzle is also inserted into the laminate sheet 29 through the opening 16.

  As shown in FIG. 6, the liquid injection device 100 includes an opening member 107 for expanding the opening 16, and the opening 16 is expanded by the opening member 107 before the nozzle 120 and the vacuuming nozzle are inserted. By widening the opening 16, the nozzle 120 and the vacuuming nozzle can easily enter the laminate sheet 29.

  The liquid injection device 100 has two opening members 107. The opening member 107 is connected to a driving unit (not shown) such as a motor or a hydraulic cylinder, for example, and the control unit 101 controls the movement of the opening member 107 by the driving unit. The two opening members 107 can move up and down, and can be separated from each other in the horizontal direction. The opening member 107 has a claw 108 extending downward. Each of the two opening members 107 descends and inserts the claw 108 into the opening 16, and then widens the opening 16 by being separated from each other in the horizontal direction.

  After the insertion of the nozzle 120 and the vacuuming nozzle into the laminate sheet 29, the two opening members 107 are lifted away from the opening 16. The seal block 104 seals the opening 16 in a state where the nozzle 120 and the vacuuming nozzle are inserted into the opening 16 (step S103, sealing step). The seal block 104 seals the opening 16 by pressing so as to sandwich the laminate sheet 29 from the outside.

  Thereafter, the control unit 101 operates the vacuum pump, and the inside of the laminate sheet 29 is evacuated (step S104). After the evacuation, the control unit 101 operates a pump connected to the nozzle 120, and the electrolyte is pressurized and injected into the laminate sheet 29 from the injection port 121 (step S105, electrolyte injection step). The electrolyte is degassed in advance.

  After injecting the electrolyte, the nozzle elevating unit 102 raises the nozzle 120 and the vacuuming nozzle, and extracts the nozzle 120 and the vacuuming nozzle from the inside of the laminate sheet 29 (step S106, extraction step). At this time, the seal block 104 is pressing so as to sandwich the laminate sheet 29 from the outside, and the sealed state is maintained.

  After extracting the nozzle 120, the sealing heater 103 presses the laminate sheet 29 so as to sandwich the laminate sheet 29 from the outside. The sealing heater 103 heat seals the opening 16 (step S107, heat sealing step). Specifically, the sealing heater 103 is heated while pressing the edges of the laminated sheet 29 that are joined together, and is joined by thermal welding.

  After heat sealing, the seal block 104 and the sealing heater 103 are separated from the laminate sheet 29. Thereafter, the operator manually moves the holding jig 110 from the electrolyte solution injection position to the battery set position, and the injection of the electrolyte solution is completed.

  The effect of this embodiment is described.

  As in the comparative example shown in FIG. 7, when the nozzle 220 having the liquid injection port at the tip 224 instead of the outer peripheral wall 223 discharges the electrolyte, the electrolyte penetrates from the upper side of the power generation element 21 where the nozzle 220 is located. Only. Accordingly, the permeation path of the electrolytic solution is limited, and it takes time to permeate the electrolytic solution. In addition, since the electrolyte injected under pressure is directly discharged from the tip 224 to the power generation element 21, there is a possibility that damage such as coating thinness / breakage may be applied to the power generation element 21.

  On the other hand, in the present embodiment, the electrolytic solution is injected from the liquid injection port 121 provided in the outer peripheral wall 123. For this reason, as shown by the arrow F <b> 1 in FIG. 8, most of the electrolytic solution travels through the laminate sheet 29 and stays on the lower side opposite to the upper side of the power generation element 21. Here, the electrolytic solution moves around the power generation element 21 through the gap 23 (see FIG. 4) between the power generation element 21 and the laminate sheet 29 and reaches the lower side of the power generation element 21. Then, as shown by the arrow F2 in FIG. 8, the staying electrolytic solution penetrates into the power generation element 21 by the capillary phenomenon. Further, the electrolytic solution penetrates into the power generation element 21 from the side of the power generation element 21 while moving around the power generation element 21 from the upper side to the lower side. Furthermore, a part of the discharged electrolyte solution rebounds upon the laminate sheet 29 as shown by an arrow F3 in FIG. Therefore, the path of the electrolytic solution is dispersed and the time until the electrolyte penetrates is shortened.

  Further, since the nozzle 120 has a plurality of liquid injection ports 121 on the entire circumference of the outer peripheral wall 123, the path of the electrolytic solution is further dispersed, and the permeation time is further shortened.

  Moreover, since the electrolyte injected under pressure is not directly discharged to the power generation element 21 but permeates indirectly as described above, it is possible to prevent the power generation element 21 from being damaged.

  In the present embodiment, the seal block 104 seals the opening 16 with the nozzle 120 inserted into the opening 16. For this reason, at the time of electrolyte solution injection | pouring, the leak of electrolyte solution is prevented and the injection volume and composition of electrolyte solution are stabilized. Further, since the seal block 104 seals the opening 16, the vacuum state is maintained when the nozzle is removed. Therefore, the electrolytic solution is not exposed to the outside air, and the injection amount and composition of the electrolytic solution are stabilized. As a result, it is not necessary to adjust the electrolyte after injection, and immediately after sealing the nozzle 120, heat sealing is performed. For this reason, the number of processes is suppressed, and work efficiency is good.

  Moreover, since the opening part 16 is heat-sealed, the injection amount and composition of the electrolytic solution are kept stable.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. For example, the liquid injection means only needs to have a liquid injection port on the outer peripheral wall, and is not limited to a linear shape as in the embodiment. For example, the liquid injection means may be tapered toward the tip. Further, the present invention is applicable not only to the above-described stacked flat battery but also to other conventionally known batteries. For example, when distinguished by structure and form, the present invention can be applied to a wound cylindrical battery or the like. In addition, when distinguishing between battery electrode materials or metal ions moving between electrodes, for example, sodium ion secondary battery, potassium ion secondary battery, nickel metal hydride secondary battery, nickel cadmium secondary battery, nickel metal hydride battery, etc. The present invention is applicable.

10 battery,
16 opening,
21 power generation elements,
29 Laminate sheet (exterior material),
100 Electrolyte injection device,
104 seal block (elastic body jig),
120 nozzles (liquid injection means),
121 injection port,
123 outer peripheral wall.

Claims (7)

A liquid injection means insertion step for inserting a liquid injection means for discharging the electrolyte into the exterior material containing the chargeable / dischargeable power generation element;
An electrolyte injection step of injecting an electrolyte from the injection means into the exterior material after the injection means insertion step;
The electrolytic solution injection step is characterized by injecting the electrolytic solution in a state in which a liquid injection port provided on a cylindrical outer peripheral wall of the liquid injection means is directed in a direction different from a direction facing the power generation element. And
After the liquid injection means insertion step and before the electrolyte injection step, it has a sealing step for sealing the exterior material, and the sealing step is performed with the liquid injection means inserted into the opening of the exterior material, A method for injecting an electrolytic solution, wherein the opening is sealed by pressing the exterior material with an elastic jig .   The method for injecting an electrolytic solution according to claim 1, wherein the electrolytic solution injecting step injects the electrolytic solution after evacuating the interior of the exterior material. 2. The method according to claim 1 , further comprising: an extraction step of extracting the liquid injection means from the interior of the exterior material after the electrolyte injection step, and a heat sealing step of heat sealing the opening after the extraction step. 2. A method for injecting an electrolytic solution according to 2. It has a liquid injection means for discharging the electrolytic solution, and is characterized in that a liquid injection port is provided on the cylindrical outer peripheral wall of the liquid injection means,
The liquid injection means is inserted into an opening of an exterior material that houses a chargeable / dischargeable power generation element, and the exterior material is exposed from the outside in a state in which the liquid injection port is directed in a direction different from the direction toward the power generation element. An electrolytic solution pouring device having an elastic jig that presses and sandwiches the opening . A controller that controls the operation of inserting the liquid injection means into the opening and the pressing operation of the exterior member by the elastic body jig;
The said control part seals the opening part of the said exterior material with the jig | tool of the said elastic body after discharging the said liquid injection means in the opening part of the said exterior material, before discharging of the said electrolyte solution. The electrolytic solution injection device described in 1 . The electrolyte solution injection device according to claim 4, further comprising a decompression unit that is inserted into an opening of the exterior material and evacuates the interior of the exterior material . The electrolyte solution injection device according to claim 4, further comprising a heat sealing unit that heat seals the opening .

Images