JP6392008B2 - Insert molding die and insert molding method - Google Patents

Description

  The present invention relates to an insert mold and an insert molding method.

  A thin battery in which an elastic resin portion is formed by insert molding in a range including an overlapping portion of the outer peripheral portion of the battery body and the spacer is known (see, for example, Patent Document 1).

JP 2012-124144 A

  When forming the elastic resin part of the thin battery, the battery body and the spacer are fixed in an insert mold. At this time, when the position of the battery body and the spacer is shifted with respect to the insert mold, the battery body and the spacer cannot be easily set on the insert mold, so that the workability at the time of molding is reduced. There is a case. In addition, if the battery body and the spacer are forced to be set in the insert mold while the position of the battery body and the spacer is shifted with respect to the insert mold, the battery body or the spacer is damaged and the yield is reduced. May be invited.

  The problem to be solved by the present invention is to provide an insert mold and an insert molding method capable of improving workability during molding and suppressing a decrease in yield.

According to the present invention, one of the insert molds includes a convex portion formed between a first part where the battery body is set and a second part where the spacer is set when the resin member is injection molded. . And the said convex part has an opposing surface which opposes a spacer at the time of the injection molding of the resin member, and the said opposing surface contains the 1st inclination part which inclines to the 1st site | part side as it goes to the front-end | tip of a convex part . The first inclined portion solves the above problem by guiding the spacer to the second portion when setting the battery body and the spacer in one mold .

  According to the present invention, when the unit cell is set in one of the insert molds, the first inclined portion guides the unit cell spacer to be set in the second part. This facilitates the setting of the unit cell in the insert mold, so that the workability during molding can be improved and the yield can be suppressed from decreasing.

FIG. 1 is a perspective view showing a secondary battery manufactured using an insert mold according to an embodiment of the present invention. FIG. 2 is an exploded perspective view showing the configuration of the secondary battery. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a plan view showing a lower mold of the insert mold according to the embodiment of the present invention. FIG. 5 is a cross-sectional view taken along line VV in FIG. FIG. 6 is a cross-sectional view for explaining the insert molding method in the embodiment of the present invention. FIG. 7 is a cross-sectional view for explaining the insert molding method in the embodiment of the present invention. FIG. 8 is a cross-sectional view for explaining the insert molding method in the embodiment of the present invention. FIG. 9 is a cross-sectional view for explaining the insert molding method in the embodiment of the present invention. FIG. 10 is a cross-sectional view for explaining the insert molding method in the embodiment of the present invention. FIG. 11 is a cross-sectional view showing a modification of the insert mold and the secondary battery in the embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing a secondary battery manufactured using the insert mold in the present embodiment, FIG. 2 is an exploded perspective view showing the configuration of the secondary battery in the present embodiment, and FIG. 2 is a cross-sectional view taken along line III-III in FIG. 4, and FIG. 4 is a plan view showing a lower mold of the insert mold according to the present embodiment.

  The secondary battery 1 manufactured using the insert mold 2 in this embodiment includes a single battery 10 and an elastic resin portion 13 provided on the outer periphery of the single battery. The unit cell 10 has a thin and flat battery body 11 and a spacer 12. The insert mold 2 in the present embodiment is a mold for forming the elastic resin portion 13 on the outer peripheral portion of the unit cell 10 constituting the secondary battery 1 by insert molding (injection molding).

In the battery body 11, a power generation element 112 is accommodated inside a pair of laminate film exterior members 111, and the pair of exterior members 111 are sealed at the outer peripheral portion 113 of the accommodation portion. 1 and 2, only one of the exterior members 111 is shown, and the power generation element 112 is shown in FIG. The laminated film constituting the exterior member 111 has, for example, a three-layer structure as shown in the drawing sectional view A of FIG. 3, and the inner resin layer 111a and the intermediate metal layer are sequentially formed from the inner side to the outer side of the secondary battery 1. 111b and the outer resin layer 111c.

  Examples of the material constituting the inner resin layer 111a include resin films excellent in electrolytic solution resistance and heat-fusibility, such as polyethylene, modified polyethylene, polypropylene, modified polypropylene, and ionomer. As a material constituting the intermediate metal layer 111b, a metal foil such as aluminum can be exemplified. Moreover, as a material which comprises the outer side resin layer 111c, the resin film excellent in electrical insulation, such as a polyamide-type resin or a polyester-type resin, can be illustrated.

  As described above, in each of the pair of exterior members 111, for example, one surface (the inner surface of the secondary battery 1) of the intermediate metal layer 111b made of aluminum foil or the like is made of polyethylene, modified polyethylene, polypropylene, modified polypropylene, or ionomer. The other surface (the outer surface of the secondary battery 1) is laminated with a polyamide-based resin or a polyester-based resin, and is formed of a flexible material such as a resin-metal thin film laminate material.

Since the pair of exterior members 111 includes the intermediate metal layer 111b in addition to the inner and outer resin layers 111a and 111c, the strength of the exterior member 111 itself can be improved. Further, the inner resin layer 111a of the exterior member 111 is made of, for example, a resin such as polyethylene, modified polyethylene, polypropylene, modified polypropylene, or ionomer, so that good fusion with the metal positive electrode terminal 114 and the negative electrode terminal 115 can be achieved. Wearability can be ensured.

  In addition, the exterior member 111 in the present invention is not limited to the three-layer structure described above, and may have a single-layer structure of the inner or outer resin layers 111a and 111c. Further, a two-layer structure of either one of the inner or outer resin layers 111a and 111c and the intermediate metal layer 111b may be used. Furthermore, the structure of four layers or more may be sufficient as needed.

  Each of the pair of exterior members 111 has a shape in which a rectangular flat plate is molded into a shallow bowl shape (dish mold) so that the power generation element 112 can be accommodated. The outer periphery 113 is overlapped, and the entire periphery of the outer periphery 113 is joined by thermal fusion or an adhesive.

  The secondary battery 1 of this example is a lithium ion secondary battery, and has a power generation element 112 configured by laminating a separator 112c between a positive electrode plate 112a and a negative electrode plate 112b, as shown in FIG. ing. The power generation element 112 of this example includes three positive plates 112a, five separators 112c, three negative plates 112b, and an electrolyte (not shown). In addition, the secondary battery 1 which concerns on this invention is not limited to a lithium ion secondary battery, For example, other batteries, such as alkaline storage batteries, such as a nickel-cadmium battery, and lead storage battery, may be sufficient.

  The positive electrode plate 112a constituting the power generation element 112 includes a positive electrode side current collector 112d extending to the positive electrode terminal 114, and positive electrode layers 112e and 112f formed on both main surfaces of a part of the positive electrode side current collector 112d, respectively. Have In this example, the positive electrode plate 112a and the positive electrode side current collector 112d are formed of a single conductor, but the positive electrode plate 112a and the positive electrode side current collector 112d are formed of different members, and You may join.

The positive electrode side current collector 112d of the positive electrode plate 112a is made of an electrochemically stable metal foil such as an aluminum foil, an aluminum alloy foil, a copper foil, or a nickel foil. The positive electrode layers 112e and 112f of the positive electrode plate 112a are made of, for example, lithium composite oxide such as lithium nickelate (LiNiO2), lithium manganate (LiMnO2) or lithium cobaltate (LiCoO2), chalcogen (S, Se, Te). a positive electrode active material products such as a conductive agent such as carbon black, and adhesive aqueous dispersion such as polytetrafluoroethylene, a mixture of a solvent, on both main surfaces of the positive electrode side current collector 112d It is formed by applying, drying and rolling.

  The negative electrode plate 112b constituting the power generation element 112 includes a negative electrode side current collector 112g extending to the negative electrode terminal 115 and negative electrode layers 112h and 112i formed on both main surfaces of a part of the negative electrode side current collector 112g, respectively. And have. In this example, the negative electrode plate 112b and the negative electrode side current collector 112g are formed of a single conductor. However, the negative electrode plate 112b and the negative electrode side current collector 112g are formed of different members, and You may join.

The negative electrode side current collector 112g of the negative electrode plate 112b is made of an electrochemically stable metal foil such as nickel foil, copper foil, stainless steel foil, or iron foil. The negative electrode layers 112h and 112i of the negative electrode plate 112b are negative electrodes that occlude and release lithium ions of the positive electrode active material, such as amorphous carbon, non-graphitizable carbon, graphitizable carbon, or graphite. An active material is mixed with an aqueous dispersion of styrene butadiene rubber resin powder as a precursor material of an organic fired body, dried and then pulverized to carry carbonized styrene butadiene rubber on the carbon particle surface. as a primary material, this was further mixed with binder such as an acrylic resin emulsion, and is formed by the mixture is applied to both main surfaces of the negative electrode side current collector 112 g, dried and rolled.

  The separator 112c laminated between the positive electrode plate 112a and the negative electrode plate 112b prevents a short circuit between the positive electrode plate 112a and the negative electrode plate 112b, and may have a function of holding an electrolyte. The separator 112c is a microporous film made of, for example, a polyolefin such as polyethylene or polypropylene. When an overcurrent flows, the separator 112c also has a function of blocking the current by closing the pores of the layer due to heat generation. However, the separator 112c is not limited to a single-layer film such as polyolefin, and a three-layer structure in which a polypropylene film is laminated with a polyethylene film interposed therebetween, or a laminate of a polyolefin microporous film and an organic nonwoven fabric can be used. Thus, by making the separator 112c into a multilayer, various functions such as an overcurrent preventing function, an electrolyte holding function, and a shape maintaining (stiffness improving) function of the separator 112c can be provided.

  The above power generation element 112 is formed by alternately stacking positive plates 112a and negative plates 112b with separators 112c interposed therebetween. The three positive plates 112a are respectively connected to the positive terminal 114 made of metal foil via the positive current collector 112d, while the three negative plates 112b are connected to the negative current collector 112g. In the same manner, each is connected to a negative electrode terminal 115 made of metal foil.

  As shown in FIG. 1, a positive electrode terminal 114 and a negative electrode terminal 115 are led out of the exterior member 111 from each of the positive electrode plate 112 a and the negative electrode plate 112 b of the power generation element 112. In the secondary battery 1 of this example, the positive electrode terminal 114 and the negative electrode terminal 115 are led out side by side from the outer peripheral portion 113a of one side of the exterior member 111 (short side in front of FIG. 2). The positive electrode terminal 114 and the negative electrode terminal 115 are also referred to as a positive electrode tab 114 and a negative electrode tab 115.

  In the secondary battery 1 of this example, the positive electrode terminal 114 and the negative electrode terminal 115 are led out from the outer peripheral portion of one side of the exterior member 111. Therefore, FIG. 3 illustrates a cross-sectional view from the positive electrode plate 112a to the positive electrode terminal 114 of the power generation element 112, and a cross section from the negative electrode plate 112b to the negative electrode terminal 115 of the power generation element 112 is omitted, but the negative electrode plate 112b and the negative electrode terminal are omitted. 115 also has the same structure as the positive electrode plate 112a and the positive electrode terminal 114 shown in the cross-sectional view of FIG. However, the positive electrode plate 112a (positive electrode side current collector 112d) and the negative electrode plate 112b (negative electrode side current collector 112g) between the end of the power generation element 112 and the positive electrode terminal 114 and the negative electrode terminal 115 are in contact with each other in plan view. Not cut in half so as not to do.

  Since the battery body 11 is rectangular in plan view, the outer peripheral portion 113 that joins a pair of exterior members 111 and seals the inside is referred to as outer peripheral portions 113a to 113d as shown in FIG. Note that the outer shape of the battery body 11 is not limited to a rectangle, and can be formed in a square or other polygons. Further, the lead-out positions of the positive electrode terminal 114 and the negative electrode terminal 115 may be derived from the respective outer peripheral portions 113a and 113b, 113c and 113d, as well as being derived from one outer peripheral portion 113a as in this example. Good. Moreover, you may make it derive | lead-out from the outer peripheral parts 113c and 113d of a long side.

  Although the battery body 11 configured as described above can be used alone, it is connected to and combined with other secondary batteries or a secondary battery having a desired output and capacity (hereinafter referred to as a battery module). It can also be used for use. Further, a plurality of such battery modules can be connected and combined (hereinafter also referred to as an assembled battery), and the assembled battery can be mounted on a vehicle such as an electric vehicle or a hybrid vehicle and used as a driving power source.

  When a plurality of battery main bodies 11 are connected to form a battery module, the main surfaces of the plurality of battery main bodies 11 are stacked and accommodated in the battery case. In this case, the positive electrode terminal 114 and the negative electrode terminal 115 derived from the outer peripheral portion 113 a of the battery body 11 and the positive electrode terminal 114 and the negative electrode terminal 115 derived from the outer peripheral portion 113 a of the battery main body 11 stacked on the battery main body 11. In order to secure the insulation between the positive electrode terminal 114 and the negative electrode terminal 115, a bus bar for connecting the positive electrode terminal 114 and the negative electrode terminal 115 in series and / or in parallel, or a connector for the voltage detection sensor is arranged. A spacer 12 made of a material is used.

  As shown in FIGS. 1 and 2, the spacer 12 of this example is disposed between the outer peripheral portions 113 a and 113 a of the battery main body 11 when the battery main bodies 11 are stacked, and the battery main body 11 is A fixing through-hole 121 for fixing to a predetermined installation position such as a battery module case or a car body is provided.

  Further, as shown in FIG. 2, a protrusion 120 is formed in the vicinity of the fixing through hole 121 in the spacer 12. The protrusions 120 are formed at arbitrary locations around the fixing through-hole 121 at both ends of the spacer 12. As shown in FIG. 2, a through-hole 1131 is formed in the outer peripheral portion 113 of the battery body 11 to which the spacer 12 is attached at a position corresponding to the protruding portion 120 of the spacer 12, and the protruding portion 120 of the spacer 12 is formed. A caulking process is applied to the tip of the protrusion 120 in a state of being inserted into the through hole 1131. The diameter of the through hole 1131 in the direction along the outer peripheral portions 113 a and 113 b of the battery body 11 is substantially equal to the diameter of the protruding portion 120. On the other hand, the diameter of the through hole 1131 in the direction in which the spacer 12 approaches or separates from the battery body 11 (perpendicular to the outer peripheral portions 113a and 113b) is slightly larger than the diameter of the protruding portion 120 ( (See FIG. 6). Thus, when the protrusion 120 of the spacer 12 is inserted into the through hole 1131, the position of the spacer 12 with respect to the battery main body 11 in the direction along the outer peripheral portions 113 a and 113 b is defined, and the spacer 12 is connected to the battery main body 11. It becomes a state in which it can approach or leave slightly.

  The spacer 12 is made of an insulating resin material having rigidity such as polybutylene terephthalate (PBT) or polypropylene (PP), and is formed in a long shape having a length equal to or longer than the outer peripheral portion 113a of the battery body 11. ing. And the fixing through-hole 121 which consists of a sheath-like through-hole is formed in each of the both ends. The length of the spacer 12 is preferably longer than the outer peripheral portion 113a to be mounted. This is because the spacer 12 as a whole receives an external force and the local stress is applied to the battery body 11. The purpose is to prevent this from working. Therefore, the length of the spacer 12 should just be a dimension as close as possible to the length of the outer peripheral part 113a with which the spacer 12 is mounted.

  Further, the mechanical strength (stiffness such as bending strength or buckling strength) of the spacer 12 made of PBT or PP described above is the electrode plate (the positive electrode plate 112a and the above-described positive electrode plate 112a) that constitutes the power generation element 112 accommodated in the battery body 11. It is desirable to make it larger than the mechanical strength of the negative electrode plate 112b). If a remarkably excessive external force acts on the spacer 12 on the secondary battery 1 or the like that is mounted on the vehicle, the spacer 12 becomes more difficult to be crushed when the spacer 12 and the power generation element 112 come into contact with each other and both are crushed. This is to ensure the holding stability of the secondary battery 1.

  In the secondary battery 1 of this example, as shown in FIG. 2, the sides 113 c and 113 d (the outer side on the long side) where the spacer 12 is not attached to the lower side outer side 113 in the figure of the battery body 11 and The elastic resin portion 13 is provided so as to cover the corner portions located at the end portions of the sides 113c and 113d. The elastic resin portion 13 is formed by elastic resin insert molding. Examples of the material constituting the elastic resin portion 13 include elastic resin materials such as vulcanized rubber, thermosetting resin elastomer, thermoplastic resin elastomer, and polyamide-based resin (hot melt grade). In addition, you may form the elastic resin part 13 in the perimeter of the outer peripheral part 113. FIG.

  The elastic resin portion 13 formed in the range H1 shown in FIG. 2 corresponds to the fixing portion 12a (see FIG. 7) to which the spacer 12 is fixed in the outer peripheral portion 113a of the battery body 11 as shown in FIGS. It is provided in the position to do. Then, when an external force such as vehicle vibration applied to the fixing through-hole 121 of the spacer 12 is transmitted from the spacer 12 to the outer peripheral portion 113a of the battery body 11, a buffering force is generated in the elastic resin portion 13 itself, The external force transmitted to the battery body 11 can be reduced.

  Note that the hardness of the elastic resin portion 13 formed in the range H <b> 1 is desirably smaller than the hardness of the outer resin layer 111 c constituting the exterior member 111 of the battery body 11. In this case, the elastic resin portion 13 can effectively absorb the external force applied to the spacer 12. The hardness of the elastic resin portion 13 can be set by appropriately selecting the type, grade, etc. of the resin material constituting the elastic resin portion 13.

  Further, in the secondary battery 1 of the present embodiment, an elastic resin portion 14 having the same shape and function as the elastic resin portion 13 is provided on the outer peripheral portion 113 on the upper side in FIG. The elastic resin portion 14 is made of the same material as that of the elastic resin portion 13 described above, and the protrusion 120 subjected to the caulking process is covered with the elastic resin portion 14. In addition, you may form the elastic resin part 13 and the elastic resin part 14 in the integrated shape which connects the outer peripheral part (part corresponded to 113c, 113d of FIG. 2) of the cell 10, and covers the said outer peripheral part.

  The insert mold 2 in the present embodiment includes a lower mold 21 and an upper mold 22 that is combined with the lower mold 21 to form a predetermined cavity.

  As shown in FIG. 4, the lower mold 21 of the insert mold 2 has a first portion 211 in which the battery body 11 of the unit cell 10 is set at the time of injection molding, and a spacer 12 of the unit cell 10 at the time of injection molding. A second portion 212. The first part 211 has a three-dimensional shape corresponding to the battery body 11 (in this example, a rectangular shape in plan view), and the second part 212 has a three-dimensional shape corresponding to the spacer 12. In the secondary battery 1 of the present embodiment, spacers 12 are attached to two opposite sides (sides corresponding to 113a and 113b in FIG. 2) in the battery body 11. Accordingly, the second portion 212 of the lower mold 21 of the insert mold 2 is also disposed along the two sides 211 a and 211 b facing each other in the first portion 211.

  A recess 213 for forming a cavity having a shape corresponding to the shape of the elastic resin portion 13 to be molded is formed outside the long side 211c of the first portion 211. In addition, a groove part 213b having a semicircular cross section is formed in a substantially central part of the long side 211c of the first part 211. Similarly, a recess 213 and a groove 213b are formed outside the long side 211d of the first part 211. Although not particularly shown, the upper mold 22 of the insert mold 2 is also formed with a semicircular groove section corresponding to the groove section 213b of the lower mold 21, and these groove sections allow the molten resin member to be recessed 213 during molding. A spool for injecting is constructed.

  The second portion 212 is provided with a locating pin 214 at a position corresponding to the fixing through hole 121 of the spacer 12. As shown in FIG. 5, the locating pin 214 has a diameter that can be inserted into the fixing through-hole 121 of the spacer 12, and when the elastic resin portion 13 is molded, the locating pin 214 is inserted into the fixing through-hole of the spacer 12. By inserting 121, the approximate position of the unit cell 10 on the lower mold 21 is defined. In the present embodiment, since the two spacers 12 fixed to the battery body 11 each have two fixing through holes 121, a total of four locating pins 214 are provided in the lower mold 21 of the insert mold 2. ing.

The lower mold 21 of the insert mold 2 in the present embodiment is provided with a pressing cylinder 215 for pressing the spacer 12 set in the second part 212 toward the first part 211 at the time of molding. Yes. The pressing cylinder 215 has a drive mechanism such as an air cylinder, a hydraulic cylinder, or a motor, for example, and the spacer 12 is pressed by the rod portion 215a moving toward the first portion 211 side by the mechanism. The As shown in FIG. 4, a total of four pressing cylinders 215 in the present embodiment are arranged at positions corresponding to the locate pins 214, but the number and arrangement of the pressing cylinders 215 are not particularly limited thereto. For example, the pressing cylinder 215 may be disposed at a position corresponding to the substantially central portion of the second portion 212.

  In the lower mold 21 of the insert mold 2 in this embodiment, a convex portion 216 is formed between the first portion 211 and the second portion 212. As shown in FIG. 4, a total of four convex portions 216 of the present embodiment are formed at positions corresponding to both end portions of the short sides 211 a and 211 b of the first portion 211. For example, the convex portions 216 may be formed at positions corresponding to the substantially central portions of the short sides 211a and 211b of the first part 211, and the convex portions so as to correspond to the entire area of the short sides 211a and 211b. 216 may be formed.

  As shown in FIG. 5, the cross-sectional shape of the convex portion 216 protrudes toward the outer peripheral portion 113 of the unit cell 10 set in the lower mold 21 between the first portion 211 and the second portion 212. It is formed as follows. The convex portion 216 has a facing surface 216a that faces the side surface 123 of the spacer 12 on the battery body 11 side during molding. The facing surface 216a includes a vertical portion 216b formed in the vertical direction with respect to the lower mold 21, and an inclined portion 216c formed above the vertical portion 216b.

  The vertical portion 216b contacts the side surface 123 of the spacer 12 on the battery body 11 side during molding. In the present embodiment, as shown in FIG. 5, a concave portion 213 (a portion forming the range H1 in FIG. 2) is provided along the vertical portion 216b.

  The inclined portion 216c is inclined toward the first portion 211 side toward the tip portion 216d of the convex portion 216. The inclined portion 216c in the present embodiment is planar, but is not particularly limited thereto. For example, the inclined portion 216c may have a curved surface shape, and a planar portion and a curved surface portion may be mixed. The inclined portion 216c in this example corresponds to an example of the first inclined portion of the present invention.

  The tip 216d of the convex part 216 faces the outer peripheral part 113 of the unit cell 10 during molding. The height of the convex portion 216 is not particularly limited, but is preferably the same height as the position of the outer peripheral portion 113 of the unit cell 10 at the time of molding from the viewpoint of improving moldability.

Although the details of the upper mold 22 of the insert mold 2 are not particularly shown, the portion corresponding to the battery body 11 of the unit cell 10 at the time of injection molding (corresponding to the first portion 211 of the lower mold 21), as in the case of the lower mold 21. And a portion corresponding to the spacer 12 (a portion corresponding to the second portion 212 in the lower mold 21). Moreover, the upper mold | type 22 is formed with the recessed part 213a for forming the elastic resin part 14 (refer FIG. 10). As described above, the upper die 22 has a groove portion at a position corresponding to the groove portion 213b formed in the lower die 21, and the groove portion of the upper die 22 and the lower die 21 causes the molten resin to enter the recess 213a. A spool for injecting is configured.

  Next, a method for manufacturing the secondary battery 1 in the present embodiment will be described. 6-10 is sectional drawing for demonstrating the insert molding method in this embodiment.

  First, the power generation element 112 is accommodated in the laminate film exterior member 111 and filled with the electrolyte, and the outer peripheral portion 113 of the exterior member 111 is sealed. Thereby, the battery main body 11 is obtained. Next, as shown in FIG. 6, the spacer 12 having the protrusion 120 is prepared, and the protrusion 120 is inserted into the through hole 1131 formed in the outer peripheral portion 113 of the exterior member 111. Subsequently, as shown in FIG. 7, with the battery main body 11 and the spacer 12 placed on the support base 30, the welding tip 31 heated to a predetermined temperature is pressed against the tip of the protrusion 120, thereby A caulking process is applied to the tip of the section 120. By this caulking process, the cell 10 in which the battery body 11 and the spacer 12 of the secondary battery 1 are temporarily fixed is obtained.

  Subsequently, the lower mold 21 of the insert mold 2 shown in FIG. 4 is prepared (first step), and the unit cell 10 is set in the lower mold 21. Specifically, the battery body 11 of the single cell 10 is set in the first portion 211, the spacer 12 of the single cell 10 is set in the second portion 212, and the lower mold is placed in the fixing through hole 121 of the spacer 12. 21 locating pins 214 are inserted (second step). At this time, as shown in FIG. 8, the diameter of the through hole 1131 is slightly larger than the diameter of the protrusion 120, so that the spacer 12 is movable in a direction approaching or moving away from the battery body 11. Yes. For this reason, when the corner portion 124 of the spacer 12 comes into contact with the inclined portion 216c of the convex portion 216 when the unit cell 10 is set, the spacer 12 slightly slides from the battery body 11 while sliding along the inclined portion 216c. Separate (see arrow in FIG. 8).

Next, as shown in FIG. 9, the lot portion 215 a of the pressing cylinder 215 moves toward the battery body 11 side of the unit cell 10. Accordingly, the spacer 12 of the cell 10 slightly moves toward the cell the body 1 1. And the side surface 123 of the said spacer 12 contacts the vertical part 216b of the convex part 216 (contact process), and the position of the spacer 12 with respect to the lower mold | type 21 of the insert mold 2 and the battery main body 11 is prescribed | regulated exactly | strictly. The four pressing cylinders 215 provided in the lower mold 21 operate in the same manner, whereby the side surfaces 123 of the spacers 12 come into contact with the vertical portions 216b of the four convex portions 216, respectively, and the position of the unit cell 10 is defined.

  Subsequently, the upper mold 22 of the insert mold 2 is set on the lower mold 21 and pressed with a predetermined pressing force to clamp the mold (see FIG. 10). Thereby, the cavity C1 for forming the elastic resin portion 13 is formed, and the cavity C2 for forming the elastic resin portion 14 is formed (third step).

Next, the molten resin material is injected from the spool of the insert mold 2 into the cavities C1 and C2 (fourth step). And after the said resin material cools, the secondary battery 1 can be obtained by releasing the battery main body 11 and the spacer 12 from the insert mold 2. As shown in FIG. 10, the elastic resin portion 14 is formed so as to cover the protruding portion 120 and also formed in the through hole 1131. This elastic resin portion 1 4 and the elastic resin portion 1 3 are secured together and the battery body 11 and the spacer 12.

  Next, the operation of the insert molding die 2 and the insert molding method using the insert molding die 2 in the present embodiment will be described.

  In the present embodiment, a convex portion 216 is formed between the first part 211 and the second part 212 in the lower mold 21 of the insert mold 2. And the opposing surface 216a of a convex part contains the inclination part 216c which inclines to the 1st site | part 211 side toward the front-end | tip part 216d of the said convex part 216. As shown in FIG.

  For this reason, when the unit cell 10 is set on the lower mold 21 of the insert mold 2, even if the unit cell 10 is displaced, the corner portion 124 of the spacer 12 contacts the inclined portion 216 c of the convex portion 216. At the same time, the spacer 12 slides along the inclined portion 216c, whereby the spacer 12 is guided to the second portion 212 (see the arrow in FIG. 8). Thereby, since setting to the lower mold | type 21 of the said cell 10 becomes easy, the improvement of workability | operativity at the time of insert molding can be aimed at. Moreover, since the single cell 10 can be prevented from being forcibly set between the lower die 21 and the upper die 22 while the single cell 10 is displaced from the lower die 21 of the insert mold 2. In addition, damage to the unit cell 10 or the spacer 12 and a decrease in yield can be suppressed.

  Further, in this embodiment, after the unit cell 10 is set on the lower mold 21 of the insert mold 2, the pressing cylinder 215 presses the spacer 12 of the unit cell 10, and the side surface 123 of the spacer 12 is moved to the convex portion 216. It is made to contact the vertical part 216b in the opposing surface 216a. Thereby, the precision improvement of the position of the cell 10 set to the lower mold | type 21 of the insert mold 2 can be aimed at.

  The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  For example, as shown in FIG. 11, the facing surface 216 a of the convex portion 216 formed on the insert mold 2 has only the inclined portion 216 c, and the side surface 123 of the spacer 12 is formed on the inclined portion 216 c of the convex portion 216. You may have the inclination part 123a which inclines along. The inclined portion 123a in this example corresponds to an example of the second inclined portion of the present invention.

  Even in this case, it is possible to improve workability when the unit cell 10 is set in the lower mold 21 of the insert mold 2 and to suppress damage to the unit cell 10 or the spacer 12 and a decrease in yield. it can. Further, the pressing cylinder 215 presses the spacer 12 to bring the inclined portion 123a of the spacer 12 into contact with the inclined portion 216c of the convex portion 216, whereby the position of the unit cell 10 set in the lower mold 21 of the insert mold 2 is determined. The accuracy can be improved.

DESCRIPTION OF SYMBOLS 1 ... Secondary battery 10 ... Single cell 11 ... Battery main body 111 ... Exterior member 112 ... Power generation element 113 ... Outer peripheral part 12 ... Spacer 12a ... Fixed part 120 ..Projection part 121... Fixing through hole 123... Side surface 123 a... Inclined part 13, 14... Elastic resin part 2. 1 part 212 ... 2nd part 1
213, 213a ... concave portion 214 ... locate pin 215 ... pressing cylinder 215a ... rod portion 216 ... convex portion 216a ... opposite surface 216b ... vertical portion 216c ... inclined portion 216d ..Tip 22: Upper mold C1, C2 ... Cavity

Claims (4)

An insert mold for injection-molding a molten resin material into the fixed portion of the unit cell comprising a battery main body having a power generation element housed in an exterior member, and a spacer having a fixed portion fixed to the battery main body. Because
One of the insert molds is
A first portion where the battery body is set during the injection molding;
A second portion where the spacer is set during the injection molding;
A convex part formed between the first part and the second part and having a facing surface facing the spacer during the injection molding,
The opposing surface is seen containing a first inclined portion inclined to the first portion side toward the tip of the convex portion,
The first inclined portion guides the spacer to the second part when setting the battery body and the spacer in the one mold.
An insert molding die characterized by that. An insert molding method for injection-molding a molten resin material into the fixed portion of a unit cell comprising: a battery main body having a power generation element housed in an exterior member; and a spacer having a fixing portion fixed to the battery main body. Because
One type is
A first portion where the battery body is set during the injection molding;
A second portion where the spacer is set during the injection molding;
A convex part formed between the first part and the second part and having a facing surface facing the spacer during the injection molding,
A first step of preparing an insert mold including a first inclined portion that is inclined toward the first portion as the facing surface is directed toward a tip of the convex portion;
A second step including a step of setting the battery body in the first portion and setting the spacer in the second portion;
A third step of setting the other mold of the insert mold for forming a cavity at a position corresponding to the fixed portion to the one mold;
And a fourth step of injecting a resin member into the cavity. The insert molding method according to claim 2,
The insert molding method according to claim 1, wherein the spacer has a second inclined portion facing the first inclined portion and inclined along the first inclined portion. The insert molding method according to claim 2 or 3,
The insert molding method according to claim 2, wherein the second step further includes a contact step of bringing the spacer set in the second portion into contact with the facing surface.

Images