JP6127960B2 - Temporary sealing jig and method of manufacturing power storage device - Google Patents

Description

  The present invention relates to a temporary sealing jig and a method for manufacturing a power storage device.

  For example, a power storage device such as a lithium ion secondary battery includes a temporary sealing step of temporarily sealing the injection port after injecting an electrolytic solution from the injection port provided in the case in the manufacturing process. is there. This is to allow the generated gas to be discharged during the manufacturing process when the gas is generated inside the power storage device during the initial charge / discharge during the manufacturing process such as an aging process. After the inlet is temporarily sealed, the case is restrained by a restraining jig, and an aging process or the like is performed. Then, the temporary sealing is opened and the gas inside the power storage device is discharged, and then the main sealing is performed. That is, temporary sealing is sealing by means that is easy to reopen. As a technique related to the temporary sealing of the inlet, for example, there is a sealed battery described in Patent Document 1. In this conventional technique, the sealing portion having elasticity and the metal plate-like body that holds the sealing portion constitute a stopper of the inlet, and the sealing portion has a constricted portion on the plate-like body side. In addition, a truncated cone portion that narrows in a tapered shape is formed on the tip side from the constricted portion.

JP 2005-190689 A

  As described above, when the temporary sealing plug is configured by the sealing portion having elasticity, there is a problem that the temporary sealing plug can be easily detached due to an impact while it can be easily attached and detached. In the above prior art, if the elastic force of the sealing portion is increased, it becomes strong against impact, but there is a possibility that the ease of attachment / detachment may be reduced. Further, if the elastic force of the sealing portion is weakened, the ease of attaching and detaching is improved, but there is a possibility that it becomes weak against impact.

  The present invention has been made to solve the above-mentioned problems, and a temporary sealing jig capable of sufficiently securing both the detachability and impact resistance of the temporary sealing plug, and an electric storage using the same. An object is to provide a method for manufacturing a device.

  In order to solve the above-mentioned problems, a temporary sealing jig according to the present invention is a method for producing an electrical storage device in which an electrode assembly and an electrolytic solution are accommodated in a case, and the electrolyte solution provided in the case is poured. A temporary sealing jig used for temporary sealing of an inlet, provided with a pin to be inserted into the injection port, and a first pressing part for pressing the first surface of the case in which the injection port is formed; When the pin is inserted into the inlet, the second pressing portion that holds the second surface of the case that intersects the first surface, and the third surface of the case that faces the second surface A third pressing portion for pressing and a pressing portion for pressing the third pressing portion toward the second pressing portion are provided.

  In this temporary sealing jig, since the first pressing portion presses the first surface of the case when the pin is inserted into the inlet, the inlet can be firmly temporarily sealed. Electrolyte leakage can be prevented. In this temporary sealing jig, when the pin is inserted into the injection port, the second pressing portion and the third pressing portion intersect the first surface by the pressing force from the pressing portion. Thus, the second surface and the third surface of the case facing each other are sandwiched, so that the shock resistance can be ensured. By releasing the pressing of the third pressing portion by the pressing portion, it is possible to sufficiently secure the ease of attaching to and detaching from the case.

  Moreover, it is preferable that the 2nd holding | suppressing part is provided with the pad which has elasticity. If it carries out like this, when clamping the 2nd surface and 3rd surface of a case with a 2nd press part and a 3rd press part, a 2nd surface can be protected by the pad which has elasticity.

  Moreover, it is preferable that the 3rd holding | suppressing part is provided with the pad which has elasticity. If it carries out like this, when clamping the 2nd surface and 3rd surface of a case with a 2nd press part and a 3rd press part, a 3rd surface can be protected by the pad which has elasticity.

  Moreover, it is preferable that a plurality of urging portions are provided so as to correspond to a direction connecting a pair of terminals provided in the case. In this case, the impact resistance can be more sufficiently ensured.

  The method for manufacturing a power storage device according to the present invention is a method for manufacturing a power storage device in which an electrode assembly is accommodated in a case, wherein the electrode assembly is accommodated in the case and then provided in the case. By injecting electrolyte solution from the inlet, and after the injection step, a temporary sealing plug having elasticity is fitted into the injection port, and the pin of the temporary sealing jig is inserted into the temporary sealing plug And a temporary sealing step of temporarily sealing the injection port.

  In this method of manufacturing the power storage device, the first pressing portion presses the first surface of the case when the pin is inserted into the inlet by the temporary sealing jig, so that the inlet is temporarily connected. The sealing plug can be firmly temporarily sealed, and leakage of the electrolyte can be prevented. In addition, when the pin is inserted into the temporary sealing plug, the second pressing portion and the third pressing portion cross the first surface and face each other by the pressing force from the pressing portion. Since the second surface and the third surface are sandwiched, the impact resistance can be ensured. By releasing the pressing of the third pressing portion by the pressing portion, it is possible to sufficiently secure the ease of attaching to and detaching from the case.

  Further, in the temporary sealing step, after the pin of the temporary sealing jig is inserted into the temporary sealing plug, the second surface and the third surface of the case which are not overlapped with the electrode assembly are temporarily sealed. It is preferable to hold between the second pressing portion and the third pressing portion of the fixing jig. In this case, in performing the impregnation step of impregnating the electrode assembly with the electrolytic solution after the temporary sealing step, it is possible to avoid delaying the impregnation of the electrolytic solution into the electrode assembly.

  Moreover, it is preferable to further include a restraining step of restraining a region overlapping the electrode assembly in the second surface and the third surface of the case after the temporary sealing step by a restraining jig. In this case, when the aging process or the like is performed after the temporary sealing process, the expansion of the electrode assembly can be suppressed.

  In the restraining step, it is preferable to provide a gap between the temporary sealing jig and the restraining jig. Thereby, interference with the temporary sealing jig and the restraining jig can be prevented.

  According to the present invention, both the ease of attaching and detaching the temporary sealing plug and the impact resistance can be sufficiently secured.

It is a perspective view which shows an example of the electrical storage apparatus manufactured by applying the manufacturing method of the electrical storage apparatus which concerns on this invention. It is sectional drawing which shows the internal structure of the electrical storage apparatus shown in FIG. It is the III-III sectional view taken on the line in FIG. It is a principal part expanded sectional view which shows an electrolyte solution injection | pouring process. It is a principal part expanded sectional view which shows the attachment state of the temporary sealing stopper in a temporary sealing process. It is a perspective view which shows the structure of the jig | tool for temporary sealing used at a temporary sealing process. It is a principal part expanded sectional view which shows the sealing state of the temporary sealing stopper in a temporary sealing process. It is a perspective view which shows the attachment state of the temporary sealing jig | tool to the case in a temporary sealing process. It is a perspective view which shows the attachment state of the restraining jig | tool to the case in a restraint process.

  Hereinafter, preferred embodiments of a temporary sealing jig and a method of manufacturing a power storage device according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating an example of a power storage device manufactured by applying the method for manufacturing a power storage device according to the present invention. 2 is a cross-sectional view showing the internal configuration, and FIG. 3 is a cross-sectional view taken along the line III-III in FIG. As shown in FIGS. 1 to 3, the power storage device 1 is configured as an in-vehicle non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. The power storage device 1 includes a hollow case 2 having a substantially rectangular parallelepiped shape, for example, and an electrode assembly 3 accommodated in the case 2.

  The case 2 is configured by, for example, a bottomed battery case can 21 whose one side is open and a lid portion 22 provided so as to close the opening of the battery case 21. The case 2 is made of a metal such as aluminum. For example, an organic solvent-based or non-aqueous electrolyte solution 4 is injected into the inside of the case 2, and voids (holes) inside the electrode assembly 3 are filled with the electrolyte solution (FIGS. 2 and 2). 3).

  As shown in FIG. 1, the positive terminal 5 and the negative terminal 6 are arranged on the lid portion 22 so as to be separated from each other. The positive electrode terminal 5 is fixed to the lid portion 22 via the insulating ring 7, and the negative electrode terminal 6 is fixed to the lid portion 22 via the insulating ring 8. In addition, an injection port 23 used when injecting the electrolytic solution 4 into the case 2 is formed at a substantially central portion of the lid portion 22. In FIG. 1, the injection port 23 is sealed by the main sealing plug 24.

  As shown in FIG. 3, the electrode assembly 3 includes a positive electrode 11, a negative electrode 12, and a bag-shaped separator 13 disposed between the positive electrode 11 and the negative electrode 12. In the electrode assembly 3, the positive electrode 11 is accommodated in the separator 13, and the positive electrode 11 and the negative electrode 12 are alternately stacked via the separator 13 in this state.

  The positive electrode 11 includes, for example, a metal foil 11a made of an aluminum foil, and a positive electrode active material layer 11b formed on both surfaces of the metal foil 11a. The positive electrode active material layer 11b is a porous layer formed including a positive electrode active material and a binder. Examples of the positive electrode active material include composite oxide, metallic lithium, and sulfur. The composite oxide includes, for example, at least one of manganese, nickel, cobalt, and aluminum and lithium. A tab 11 c is formed on the upper edge of the positive electrode 11 in correspondence with the position of the positive electrode terminal 5. The tab 11 c extends upward from the upper edge portion of the positive electrode 11 and is connected to the positive electrode terminal 5 via the conductive member 14.

  On the other hand, the negative electrode 12 includes, for example, a metal foil 12a made of copper foil and a negative electrode active material layer 12b formed on both surfaces of the metal foil 12a. The negative electrode active material layer 12b is a porous layer formed including a negative electrode active material and a binder. Examples of the negative electrode active material include carbon such as graphite, highly oriented graphite, mesocarbon microbeads, hard carbon, and soft carbon, alkali metals such as lithium and sodium, metal compounds, SiOx (0.5 ≦ x ≦ 1.5 ) And the like, and boron-added carbon. A tab 12 c is formed on the upper edge of the negative electrode 12 in correspondence with the position of the negative electrode terminal 6. The tab 12 c extends upward from the upper edge of the negative electrode 12, and is connected to the negative electrode terminal 6 via the conductive member 15.

  The separator 13 is formed in a bag shape, for example, and accommodates only the positive electrode 11 therein. Examples of the material for forming the separator 13 include a porous film made of a polyolefin resin such as polyethylene (PE) and polypropylene (PP), a woven fabric or a non-woven fabric made of polypropylene, polyethylene terephthalate (PET), methylcellulose and the like. The separator 13 is not limited to a bag shape, and a sheet shape may be used.

  Then, the manufacturing method of the electrical storage apparatus 1 mentioned above is demonstrated. The manufacturing process of the power storage device 1 includes, for example, an electrolyte injection process for injecting the electrolyte solution 4 into the case 2, a temporary sealing process for temporarily sealing the injection port 23 of the case 2, The restraint process restrained with the tool 61 is comprised.

  Prior to the electrolytic solution injection step, first, the electrode assembly 3 is accommodated in the battery case 21 and the battery case 21 and the lid portion 22 are joined by welding or the like. In the electrolytic solution injection step, as shown in FIG. 4, for example, a foot portion of a funnel-shaped container 25 containing the electrolytic solution 4 is inserted into the injection port 23 of the case 2, and the electrolytic solution 4 is injected into the case 2. The injected electrolyte 4 is impregnated inside the electrode assembly and fills the voids (holes) inside the active material and the separator.

  In the temporary sealing step subsequent to the electrolytic solution injection step, first, a temporary sealing plug 31 is attached to the injection port 23 as shown in FIG. The temporary sealing plug 31 is made of an elastic material such as ethylene propylene diene rubber. The temporary sealing plug 31 has a cylindrical protruding portion 32 and a flange portion 33 formed on the peripheral edge on the proximal end side of the protruding portion 32. In addition, a pin insertion port 34 extending toward the distal end side inside the protrusion 32 is formed at a substantially central portion on the base end side of the protrusion 32. The temporary sealing plug is attached to the injection port 23 by the protrusion 32 being fitted into the injection port 23 until the flange portion 33 contacts the surface of the lid portion 22.

  Next, in the temporary sealing step, the temporary sealing plug 31 fitted into the injection port 23 is sealed using the temporary sealing jig 41. As shown in FIG. 6, the temporary sealing jig 41 is provided with a pin 43 to be inserted into the injection port 23, and holds the first surface 22 a of the lid portion 22 in the case 2. A pressing portion 42, a second pressing portion 44 that presses one side surface (second surface) 2a in the thickness direction of the case 2, and the other side surface (third surface) 2b in the thickness direction of the case 2 are A third pressing portion 45 for pressing and two pressing portions 46 and 46 for pressing the third pressing portion 45 toward the second pressing portion 44 are provided. The first pressing part 42, the second pressing part 44, and the third pressing part 45 are made of a resin material such as polyphenylene sulfide resin, and the pin 43 is made of stainless steel, for example.

  The first pressing portion 42 has, for example, a substantially rectangular parallelepiped shape. The pin 43 described above is provided at a substantially central portion of the first pressing portion 42 on the side surface 42a side in the thickness direction. Further, the second pressing portion 44 is formed in a plate shape in the same direction as the pin 43 and is substantially equal in width to the first pressing portion 42 at one end side in the length direction of the side surface 42 a of the first pressing portion 42. It protrudes. A pad 47 made of an elastic material such as rubber is provided on the entire inner surface 44 a of the second pressing portion 44.

  The third pressing portion 45 has, for example, a substantially rectangular parallelepiped shape wider than the second pressing portion 44, and the second pressing portion 44 on the other end side in the length direction of the side surface 42 a of the first pressing portion 42. Are arranged to face each other. A pad 48 formed of an elastic material such as rubber is provided on the entire inner surface 45 a of the third pressing portion 45, similarly to the second pressing portion 44. Further, triggers 49 and 49 for operating the third pressing portion 45 are provided at both ends in the width direction of the third pressing portion 45 on the outer surface 45b side.

  The pressing portion 46 includes a bolt 51 inserted through a plate-like portion 50 that protrudes substantially parallel to the second pressing portion 44, and the bolt 51 on the other end side in the length direction of the side surface 42 a of the first pressing portion 42. And a spring 52 passed through the threaded portion 51a. In the present embodiment, the plate-like portion 50 is provided with two bolt insertion holes with a predetermined interval in the width direction, and the screw portion 51a of the bolt 51 is in a state of being passed through the bolt insertion hole. The tip of the screw part 51 a that has passed through the bolt insertion hole is fixed to the outer surface 45 b of the third pressing part 45 between the triggers 49 and 49.

  Further, the spring 52 is passed through the threaded portion 51 a of the bolt 51 between the inner side surface 50 a of the plate-like portion 50 and the outer side surface 45 b of the third pressing portion 45. The third pressing portion 45 is always urged toward the second pressing portion 44 by the spring 52. Further, the amount of movement of the third pressing portion 45 toward the second pressing portion 44 is restricted at a position where the head 51 b of the bolt 51 hits the outer surface 50 b of the plate-like portion 50. By operating the triggers 49 and 49 and pulling the third pressing portion 45 toward the plate-like portion 50 against the biasing force of the spring 52, the interval between the second pressing portion 44 and the third pressing portion 45 is increased. Can be spread.

  In the temporary sealing process using the temporary sealing jig 41 as described above, first, the triggers 49 and 49 of the temporary sealing jig 41 are pulled, and the second pressing part 44 and the third pressing part 45 are pulled. As shown in FIG. 7, the pin 43 is inserted into the pin insertion port 34 of the temporary sealing plug 31. Thereby, the temporary sealing plug 31 is pushed and expanded by the pin 43 in the injection port 23, and the injection port 23 is firmly sealed with the temporary sealing plug 31. In addition, since the first pressing portion 42 presses the surface of the lid portion 22 of the case 2 in a state where the pin 43 is inserted into the pin insertion port 34 of the temporary sealing plug 31, a stable sealing state is maintained.

  Next, the triggers 49 and 49 of the temporary sealing jig 41 are returned, and the third pressing portion 45 is pressed toward the second pressing portion 44. As a result, as shown in FIG. 8, the second pressing portion 44 and the third pressing portion 45 hold the side surface 2a and the side surface 2b of the case 2 so that the temporary sealing jig 41 has an impact caused by dropping or the like. Even if added, it is possible to prevent the temporary sealing jig 41 from being detached from the case 2. At this time, the second pressing portion 44 and the third pressing portion 45 are respectively provided with pads 47 and 48 made of an elastic material, and the second pressing portion 44 and the third pressing portion. The side surfaces 2a and 2b of the case 2 are protected against 45 pressing.

  Further, in a state where the temporary sealing jig 41 is attached to the case 2, the two pressing portions 46 and 46 are arranged in a direction connecting the positive electrode terminal 5 and the negative electrode terminal 6 of the case 2. As a result, the posture of the third pressing portion 45 when the triggers 49 are operated is stabilized, and the temporary sealing jig 41 is impacted from the direction connecting the positive electrode terminal 5 and the negative electrode terminal 6. Therefore, a stable sealing state is more reliably maintained. In addition, since the temporary sealing jig 41 is maintained by sandwiching the side surface 2a and the side surface 2b of the case 2, stable temporary sealing can be achieved without depending on the main sealing means and the structure of the injection port. Can be maintained.

  When removing the temporary sealing jig 41 from the case 2, the triggers 49, 49 are pulled toward the plate-like portion 50, and the interval between the second pressing portion 44 and the third pressing portion 45 is widened again. And it is sufficient. The temporary sealing jig 41 can be easily attached to and detached from the case 2 by releasing the pressing of the third pressing portion 45 by the pressing portion 46.

  In the temporary sealing jig 41, the protruding lengths of the second pressing part 44 and the third pressing part 45 from the side surface 42a of the first pressing part 42 are the same as the temporary sealing jig 41. In the state attached to 2, it is preferable that the length does not overlap with the electrode assembly 3 in the case 2. In this case, after inserting the pin of the temporary sealing jig 41 into the pin insertion port 34 of the temporary sealing plug 31, the region of the side surfaces 2 a and 2 b of the case 2 that does not overlap the electrode assembly 3 is the second. It is clamped by the pressing part 44 and the third pressing part 45. Therefore, when the impregnation step of impregnating the electrode assembly 3 with the electrolytic solution 4 is performed after the temporary sealing step, it is possible to avoid delaying the impregnation of the electrolytic solution 4 into the electrode assembly 3.

  In the restraining step subsequent to the temporary sealing step, the case 2 is restrained using a pair of restraining jigs 61 and 61. As shown in FIG. 9, the restraining jig 61 is made of a metal plate-like member having a width wider than that of the case 2, and both end portions in the width direction are arranged so as to sandwich the case 2 in the thickness direction. A predetermined restraining pressure is applied in the thickness direction of the case 2 by tightening the bolts 62 at the top and bottom two places.

  The height of the restraining jig 61 is smaller than the height of the case 2, and the restraining jig 61 is attached to the case 2 with the bottom of the case 2 and the bottom of the restraining jig 61 aligned. In this case, regions of the side surfaces 2 a and 2 b of the case 2 that do not overlap with the electrode assembly 3 are sandwiched by the restraining jigs 61 and 61. Thereby, in performing an aging process etc. after a temporary sealing process, expansion of the electrode assembly 3 can be suppressed. Further, when the restraining jig 61 is attached, a gap G is provided between the temporary sealing jig 41 and the restraining jig 61 as shown in FIG. As a result, interference between the temporary sealing jig 41 and the restraining jig 61 is avoided.

  After the restraining process, an aging process (initial charge / discharge) is performed. After the aging process, the temporary sealing jig 41 and the temporary sealing plug 31 are removed, and after the degassing process and the like, the main sealing of the inlet 23 is performed. The main sealing means that it is difficult to reopen, for example, a metal pin is inserted into the injection port 23 and welded / sealed by laser welding, or sealed / sealed using a blind rivet. It is the sealing which makes a state. Thereafter, the power storage device 1 shown in FIGS. 1 to 3 is obtained through a process of self-discharging the electrode assembly 3 and the like.

  The present invention is not limited to the above embodiment. For example, in the above embodiment, the injection port 23 is temporarily sealed by inserting the pin 43 of the temporary sealing jig 41 into the pin insertion port 34 of the temporary sealing plug 31 through the temporary sealing plug 31. For example, the pin of the temporary sealing jig 41 is formed of an elastic member having substantially the same diameter as the injection port 23, and the pin is inserted directly into the injection port 23 without using the temporary sealing plug 31 to perform temporary sealing. It may be. Moreover, in the said embodiment, although the press part 46 of the jig | tool 41 for temporary sealing is comprised by the volt | bolt 51 and the spring 52, the structure of the press part 46 is not restricted to this, For example, bolting etc. Other means may be used.

  DESCRIPTION OF SYMBOLS 1 ... Power storage device, 2 ... Case, 2a ... Side surface (2nd surface), 2b ... Side surface (3rd surface), 3 ... Electrode assembly, 4 ... Electrolyte solution, 5 ... Positive electrode terminal, 6 ... Negative electrode terminal, 22a ... The surface (first surface) of the lid part, 23 ... Injection port, 31 ... Temporary sealing plug, 41 ... Temporary sealing jig, 42 ... First pressing part, 43 ... Pin, 44 ... Second 45, a third pressing portion, 46, a pressing portion, 47, 48, a pad, 61, a restraining jig, G, a gap.

Claims (8)

A temporary sealing jig used for temporary sealing of an inlet of the electrolytic solution provided in the case in a manufacturing process of a power storage device in which an electrode assembly and an electrolytic solution are accommodated in a case. ,
A pin that is inserted into the injection port, and a first pressing portion that holds the first surface of the case in which the injection port is formed;
A second pressing portion that presses the second surface of the case that intersects the first surface when the pin is inserted into the inlet;
A third pressing portion that presses the third surface of the case facing the second surface;
A temporary sealing jig, comprising: a pressing portion that presses the third pressing portion toward the second pressing portion.   The temporary sealing jig according to claim 1, wherein an elastic pad is provided on the second pressing portion.   The temporary sealing jig according to claim 1, wherein an elastic pad is provided on the third pressing portion.   4. The temporary sealing treatment according to claim 1, wherein a plurality of the pressing portions are provided so as to correspond to a direction connecting a pair of terminals provided in the case. 5. Ingredients. A method of manufacturing a power storage device in which an electrode assembly is housed in a case,
An electrolytic solution injecting step of injecting an electrolytic solution from an injection port provided in the case after accommodating the electrode assembly in the case;
After the injection step, a temporary sealing plug having elasticity is fitted into the injection port, and the pin of the temporary sealing jig according to any one of claims 1 to 4 is inserted into the temporary sealing plug. And a temporary sealing step of temporarily sealing the injection port.   In the temporary sealing step, after the pin of the temporary sealing jig is inserted into the temporary sealing plug, the electrode assembly of the second surface and the third surface of the case 6. The method for manufacturing a power storage device according to claim 5, wherein a region that does not overlap is sandwiched between the second pressing portion and the third pressing portion of the temporary sealing jig.   After the temporary sealing step, the method further comprises a restraining step of restraining a region overlapping the electrode assembly in the second surface and the third surface of the case with a restraining jig. The manufacturing method of the electrical storage apparatus of Claim 6.   8. The method of manufacturing a power storage device according to claim 7, wherein a gap is provided between the temporary sealing jig and the restraining jig in the restraining step.

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