Method for manufacturing an electricity storage device

Abstract

To provide a method of manufacturing a power storage device, and the like, capable of suppressing generation of a burned part on a resin member for isolating between a lid member and terminal members due to scattered light of laser light at laser welding.SOLUTION: A method of manufacturing a power storage device 1 includes: an arrangement step S2 of closing an opening 21 of a main body member 20 with a lid member 30 of a lid assembly 7 obtained by integrating terminal members 50 and 60 to the lid member 30 via resin members 70 and 80; and a welding step S3 of laser welding the whole circumference of the opening 21 of the main body member 20 and a peripheral edge part 31 of the lid member 30. In the arrangement step S2, a circumferential high region ST where a circumferential outer lateral face 31m of the peripheral edge part 31 of the lid member 30 is located outside DH1 an opening end surface 21m of the opening 21 of the main body member 20 is provided at a proximity long side opening 21be and a proximity long side peripheral edge part 31be of the opening 21 and the peripheral edge part 31.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing an electricity storage device, such as a battery or a capacitor, in which a terminal member is fixed to a case via a resin member. [Background technology]

[0002] As an electricity storage device, a rectangular battery is known in which positive and negative terminal members are fixed to a rectangular box-shaped case via a resin member. Specifically, the case is composed of a bottomed rectangular cylindrical main body member having an opening, and a plate-shaped lid member laser-welded to the main body member over the entire circumference in a form that closes the opening. The positive and negative terminal members are inserted into a pair of insertion holes drilled in the lid member, respectively, and extend from the inside of the case to the outside of the case. A pair of resin members are joined to the lid member and the terminal members, respectively, while insulating the lid member from the positive and negative terminal members. For example, Patent Document 1 can be cited as a related prior art (see Figures 1 and 2 of Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-086813 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the manufacturing process of such a battery, the opening of the main body member is closed with a cover member to which a terminal member is fixed in advance, and the opening of the main body member and the peripheral portion of the cover member are laser-welded over the entire circumference. During this process, scattered light of the laser light is irradiated onto the resin member that insulates between the cover member and the terminal member, and may cause a scorched portion in the resin member. Note that this scorched portion is likely to occur in a portion of the resin member that is close to the melted and solidified portion formed by laser welding, specifically, in a portion close to a pair of long side openings of the rectangular annular opening of the main body member and a pair of long side peripheral portions of the rectangular annular peripheral portion of the cover member.

[0005] The present invention has been made in consideration of the current situation, and provides a manufacturing method for an electricity storage device that can suppress the occurrence of scorched areas in the resin member that insulates between the cover member and the terminal member due to scattered laser light when the main body member and the cover member are laser welded to form a case. [Means for solving the problem]

[0006] (1) One aspect of the present invention for solving the above problem is a method for manufacturing an electricity storage device including: a bottomed, tubular main body member having a rectangular annular opening having a pair of long side openings and a pair of short side openings; and a lid member having a rectangular annular peripheral portion having a pair of long side peripheral portions and a pair of short side peripheral portions, the lid member being laser welded to the main body member around its entire circumference in a manner that closes the opening; a terminal member inserted into an insertion hole penetrating the lid member in a lid thickness direction; and a resin member joined to the insertion hole peripheral portion of the lid member and the terminal member while insulating between an insertion hole peripheral portion surrounding the insertion hole of the lid member and the terminal member, wherein the lid assembly is formed by integrating the terminal member with the lid member via the resin member, and the pair of long side peripheral portions of the lid member are opposed to the pair of long side openings of the main body member and the pair of short side peripheral portions of the lid member are opposed to the pair of short side openings of the main body member, respectively, to form an upper and a welding step of forming the case by performing laser welding over the entire circumference in which a laser beam is irradiated from the outside of the cover member in the cover thickness direction to melt and mix the opening of the body member and a peripheral portion of the cover member and then solidify the melted and solidified portion, wherein the arrangement step provides a peripheral high-level region in which a peripheral outer surface facing the outside of the peripheral portion of the cover member is positioned outside of an opening end surface facing the outside of the opening of the body member, at least in a proximal long side opening of the pair of long side openings that is proximal to the resin member, and in a proximal long side peripheral portion of the pair of long side peripheral portions that is proximal to the resin member, among the opening and the peripheral portion, and the welding step forms the melted and solidified portion in a form in which the peripheral outer surface of the cover member is positioned outside of the melted and solidified portion in the peripheral high-level region. The opening of the main body member has a configuration in which the proximal long side opening is located more inward in the thickness direction of the lid than other portions of the opening. A method for manufacturing an electricity storage device.

[0007] In the above-mentioned method for manufacturing an electric storage device, in the arranging step, the lid assembly is arranged on the main body member, so that a high peripheral region in which the outer peripheral surface of the peripheral portion of the lid member is located outside the opening end surface of the opening of the main body member in the lid thickness direction is provided at least in the proximal long side opening and the proximal long side peripheral portion of the opening of the main body member and the peripheral portion of the lid member. Then, in the welding step, a melted solidified portion is formed in the high peripheral region in such a manner that the outer peripheral surface of the lid member is located outside the melted solidified portion. As a result, in the welding step, the molten metal portion formed by the irradiation of the laser light in the high peripheral region has a shape having a slope that becomes lower as it moves away from the resin member. Therefore, the scattered light of the laser light irradiated to this slope is unlikely to be irradiated to the resin member, and a scorched portion is unlikely to be generated in the resin member. In particular, it is possible to suppress the generation of a scorched portion in a peripheral vicinity portion of the resin member that is close to the proximal long side opening and the proximal long side peripheral portion and is likely to be scorched. In addition, in the high peripheral region, since the outer peripheral surface of the cover member is located outside the molten and solidified portion, water and dust are less likely to accumulate on the cover member of the energy storage device than when part of the molten and solidified portion is located outside the outer peripheral surface of the cover member. Furthermore, in the method for manufacturing the electric storage device described above, a body member is used in which the proximal long side opening of the opening is located further inward in the lid thickness direction than other parts of the opening. By using such a body member, it is possible to easily provide the above-mentioned peripheral high area in the proximal long side opening of the opening and the proximal long side peripheral part of the peripheral part when the lid assembly is arranged in the arrangement step.

[0008] In addition 、「 Examples of the "lid member" include a plate-shaped lid member, a lid member whose central portion excluding the peripheral portion bulges outward from the peripheral portion of the lid member, and a lid member whose central portion is recessed inward from the peripheral portion of the lid member. Examples of "electricity storage devices" include secondary batteries such as lithium ion secondary batteries, capacitors such as lithium ion capacitors, and all-solid-state batteries.

[0013] ( 2Another aspect is a case including a bottomed cylindrical main body member having a rectangular annular opening having a pair of long side openings and a pair of short side openings, and a cover member having a rectangular annular peripheral portion having a pair of long side peripheral portions and a pair of short side peripheral portions, the case being laser welded to the main body member over the entire circumference in a manner to close the opening, the cover member having a rectangular annular peripheral portion having a pair of long side peripheral portions and a pair of short side peripheral portions, a terminal member inserted into an insertion hole penetrating the cover member in the thickness direction of the cover, and a terminal member inserted into the insertion hole peripheral portion and the upper portion of the cover member while insulating between the insertion hole peripheral portion surrounding the insertion hole of the cover member and the terminal member. and a resin member joined to each of the terminal members, wherein at least one of the pair of long side openings of the opening of the main body member and the peripheral portion of the lid member that is adjacent to the resin member and one of the pair of long side peripheral portions that faces the adjacent long side opening and is adjacent to the resin member among the pair of long side peripheral portions are positioned outside a melted and solidified portion formed after the opening and the peripheral portion are melted and mixed. The opening of the main body member has a configuration in which the proximal long side opening is located more inward in the thickness direction of the lid than other portions of the opening. It is an electricity storage device.

[0014] In the above-described electricity storage device, the occurrence of scorched portions is suppressed in the resin member near the proximal long side opening and the proximal long side peripheral portion where scorched portions are likely to occur, so that the original appearance of the resin member can be maintained and a decrease in insulation resistance between the lid member and the terminal member via the scorched portions can be suppressed. In addition, since the peripheral outer surface of the lid member is located outside the melt-solidified portion for the proximal long side opening and the proximal long side peripheral portion, water and dust are less likely to accumulate on the lid member of the electricity storage device compared to a case in which a part of the melt-solidified portion is located outside the peripheral outer surface of the lid member. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view of a battery according to a reference embodiment. [Diagram 2] 1 is a cross-sectional view of a battery according to a reference embodiment taken along a battery height direction and a battery width direction. [Diagram 3]1A and 1B are partially enlarged cross-sectional views of the opening of the main body member and the peripheral portion of the cover member of a battery of a reference embodiment, where (a) is a partially enlarged cross-sectional view along the battery height direction and battery width direction, and (b) is a partially enlarged cross-sectional view along the battery height direction and battery thickness direction. [Figure 4] 4 is a flowchart of a method for manufacturing a battery according to a reference embodiment. [Diagram 5] 10 is an explanatory diagram showing a lid assembly formed in a lid assembly forming step in a manufacturing method for a battery according to a reference embodiment. FIG. [Figure 6] 11 is an explanatory diagram showing a state in which a lid assembly is arranged so as to cover an opening of a body member with a lid member constituting the lid assembly in an arrangement step in a manufacturing method for a battery according to a reference embodiment. FIG. [Figure 7] 1A is an explanatory diagram showing the state in which the opening (near long side opening) of the main body member and the peripheral portion (near long side peripheral portion) of the cover member are laser welded in the welding process of a battery manufacturing method of a reference embodiment, where (a) is an explanatory diagram showing the state in which the irradiation of laser light is started, and (b) is an explanatory diagram showing the state in which a molten metal portion is formed by the irradiation of laser light. [Figure 8] FIG. 2A is a side view and FIG. 2B is a top view of a main body member of a battery according to an embodiment. [Figure 9] 8A and 8B are explanatory diagrams corresponding to FIG. 7 and relating to a manufacturing method for a battery according to a comparative embodiment, in which (a) is an explanatory diagram showing the start of irradiation of laser light, and (b) is an explanatory diagram showing the formation of a molten metal portion by irradiation of laser light. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] ( Reference form ) The present invention will be described below. Reference form The following will be described with reference to the drawings. Reference formFIG. 2 shows a perspective view of the battery (electricity storage device) 1 according to the present invention, FIG. 2 shows a cross-sectional view of the entire battery 1, and FIG. 3 shows an enlarged cross-sectional view of a portion of the battery 1 near an opening 21 of a main body member 20 and a peripheral portion 31 of a lid member 30. In the following description, the battery height direction AH, battery width direction BH, and battery thickness direction CH of the battery 1 are defined as the directions shown in FIG. 1 to FIG. 3. The battery 1 is a rectangular (rectangular) sealed lithium ion secondary battery that is mounted on vehicles such as hybrid cars, plug-in hybrid cars, and electric cars.

[0019] The battery 1 is composed of a case 10, an electrode body 40 contained in the case 10, and positive and negative terminal members 50, 60 supported on a case upper portion 11 of the case 10 via resin members 70, 80. Inside the case 10, the electrode body 40 is covered by a bag-shaped insulating holder 5 made of an insulating film and opening to an upper side AH1 in the battery height direction AH. An electrolyte 3 is also contained inside the case 10, a part of which is impregnated into the electrode body 40 and the remainder is pooled on the case bottom portion 12 of the case 10.

[0020] Of these, case 10 is made of metal (main Reference form The battery has a rectangular box shape made of aluminum (in the example shown) and has a rectangular case upper part 11 located on the upper side AH1 in the battery height direction AH, a rectangular case bottom part 12 facing the rectangular case upper part 11 and located on the lower side AH2 in the battery height direction AH, and four rectangular case sides (a pair of case long sides 13, 14 and a pair of case short sides 15, 16) connecting the two.

[0021] The case 10 is composed of a main body member 20 and a lid member 30. The main body member 20 is a rectangular cylindrical member with a bottom having a rectangular annular opening 21 including a pair of long side openings 21b and a pair of short side openings 21c on the upper side AH1 in the battery height direction AH, and constitutes the case bottom 12, the case long side parts 13, 14, and the case short side parts 15, 16 of the case 10. On the other hand, the lid member 30 is a rectangular plate and constitutes the case upper part 11 of the case 10. The lid member 30 is laser welded to the main body member 20 over its entire circumference in a manner that closes the opening 21 of the main body member 20, and a melt-solidified part 18 is formed between the lid member 30 and the main body member 20.

[0022] Specifically, a pair of long side openings 21b of the rectangular annular opening 21 of the main body member 20 are welded to a pair of long side peripheral edges 31b of the rectangular annular peripheral edge 31 of the cover member 30 to form the melted and solidified portion 18 (see FIG. 3(b)). Also, a pair of short side openings 21c of the opening 21 of the main body member 20 are welded to a pair of short side peripheral edges 31c of the peripheral edge 31 of the cover member 30 to form the melted and solidified portion 18 (see FIG. 3(a)). Reference form Here, around the entire circumference of the opening 21 and peripheral portion 31, including the adjacent long side opening 21be of the pair of long side openings 21b that is adjacent to the resin members 70, 80, and the adjacent long side peripheral portion 31be of the pair of long side peripheral portions 31b that is adjacent to the resin members 70, 80, the peripheral outer surface 31m of the peripheral portion 31 that faces the outer side DH1 in the lid thickness direction DH (upper side AH1 in the battery height direction AH) is located outer DH1 (upper side AH1) than the molten and solidified portion 18 (the position of the peripheral outer surface 31m in the lid thickness direction DH is indicated by dashed line M in Figures 3(a) and (b)).

[0023] The cover member 30 is provided with a safety valve 19 that breaks and opens when the internal pressure of the case 10 exceeds the valve opening pressure. The cover member 30 is also formed with a liquid injection hole 30k that communicates between the inside and outside of the case 10, and is airtightly sealed with a disk-shaped sealing member 39 made of aluminum. The lid member 30 has rectangular insertion holes 33h, 34h near an end of one side BH1 in the battery width direction BH and near an end of the other side BH2, respectively, penetrating in the lid thickness direction DH. A positive electrode terminal member 50 made of aluminum is inserted into one of the insertion holes 33h, and is fixed to the lid member 30 in a state insulated from the lid member 30 via a resin member 70. A negative electrode terminal member 60 made of copper is inserted into the other insertion hole 34h, and is fixed to the lid member 30 in a state insulated from the lid member 30 via a resin member 80.

[0024] These terminal members 50, 60 each have a rectangular plate-shaped external terminal portion 51, 61 arranged on the cover member 30, and an internal terminal portion 52, 62 arranged mainly inside the case 10 and connected to the external terminal portion 51, 61 via the insertion holes 33h, 34h of the cover member 30. The positive electrode internal terminal portion 52 is joined to and conductively connected with the positive electrode tab 40a of the electrode body 40 inside the case 10. On the other hand, the negative electrode internal terminal portion 62 is joined to and conductively connected with the negative electrode tab 40b of the electrode body 40 inside the case 10.

[0025] The positive electrode resin member 70 surrounds the insertion hole 33h of the lid member 30, and is joined to the insertion hole surrounding portion 33 of the lid member 30 and the terminal member 50 while providing insulation between the terminal member 60 and the rectangular annular insertion hole surrounding portion 33 having a pair of long side peripheral portions 33e and a pair of short side peripheral portions 33f. Similarly, the negative electrode resin member 80 surrounds the insertion hole 34h of the lid member 30, and is joined to the insertion hole surrounding portion 34 of the lid member 30 and the terminal member 60 while providing insulation between the terminal member 60 and the rectangular annular insertion hole surrounding portion 34 having a pair of long side peripheral portions 34e and a pair of short side peripheral portions 34f.

[0026] These resin members 70, 80 are made of polyphenylene sulfide (PPS) and have rectangular plate-shaped external insulating parts 71, 81 arranged on the cover member 30, and internal insulating parts 72, 82 arranged inside the case 10 and in the insertion holes 33h, 34h of the cover member 30 and connected to the external insulating parts 71, 81. Of these, the external insulating parts 71, 81 insulate between the external terminal parts 51, 61 of the terminal members 50, 60 and the insertion hole surrounding parts 33, 34 of the cover member 30. On the other hand, the internal insulating parts 72, 82 insulate between the internal terminal parts 52, 62 of the terminal members 50, 60 and the insertion hole surrounding parts 33, 34 of the cover member 30.

[0027] The electrode body 40 is a flat rectangular parallelepiped, and is a laminated electrode body in which a plurality of positive electrode plates 41 and a plurality of negative electrode plates 42, each of which has a rectangular shape extending in the battery height direction AH and the battery width direction BH, are alternately laminated in the battery thickness direction CH via a separator 43 made of a porous resin film. Each positive electrode plate 41 has a positive electrode current collector 41r extending to the upper side AH1, and the positive electrode current collectors 41r overlap each other in the thickness direction to form the above-mentioned positive electrode tab 40a. This positive electrode tab 40a is connected to the internal terminal portion 52 of the positive electrode terminal member 50 as described above. Each negative electrode plate 42 has a negative electrode current collector 42r extending to the upper side AH1, and the negative electrode current collectors 42r overlap each other in the thickness direction to form the above-mentioned negative electrode tab 40b. This negative electrode tab 40b is connected to the internal terminal portion 62 of the negative electrode terminal member 60 as described above.

[0028] Books Reference form In the battery 1, the occurrence of scorched areas BP (see FIG. 9(b)) is suppressed in peripheral adjacent regions 70e, 80e (see FIG. 3(b)) of the resin members 70, 80 that are adjacent to the proximal long side opening 21be and the proximal long side peripheral portion 31be and are prone to scorched areas BP, and further, the occurrence of scorched areas BP is suppressed over the entire circumference of the resin members 70, 80. As a result, the original appearance of the resin members 70, 80 can be maintained over the entire circumference of the resin members 70, 80, and a decrease in insulation resistance between the cover member 30 and the terminal members 50, 60 via the scorched areas BP that have occurred can be suppressed. Also, Reference form In the proximal long side opening 21be and the proximal long side peripheral portion 31be, and further over the entire circumference of the opening 21 and the peripheral portion 31, the peripheral outer surface 31m of the lid member 30 is located on the outer side DH1 of the melt-solidified portion 18. For this reason, water and dust are unlikely to accumulate on the lid member 30 (case upper portion 11) of the battery 1.

[0029] Next, a method for manufacturing the battery 1 will be described (see Figs. 4 to 7). First, in the "lid assembly forming step S1" (see Fig. 4), the lid assembly 7 is formed (see Fig. 5). That is, the lid member 30 and the terminal members 50, 60 are prepared, and the resin members 70, 80 are insert-molded to integrate the terminal members 50, 60 with the lid member 30 via the resin members 70, 80. Specifically, the lid member 30 is obtained by using an aluminum plate and forming the liquid injection hole 30k, the insertion holes 33h, 34h, and the safety valve 19 by pressing. The positive electrode terminal member 50 is obtained by pressing an aluminum plate, and the negative electrode terminal member 60 is obtained by pressing a copper plate. Then, with the terminal members 50, 60 inserted into the insertion holes 33h, 34h of the lid member 30, the resin members 70, 80 are insert-molded to integrate the terminal members 50, 60 with the lid member 30 via the resin members 70, 80.

[0030] Next, an electrode body 40 formed by stacking a positive electrode plate 41, a negative electrode plate 42, and a separator 43 is prepared, and the internal terminal portions 52, 62 of the terminal members 50, 60 integrated with the above-mentioned lid member 30 are connected to the positive electrode tab 40a and the negative electrode tab 40b of the electrode body 40 by welding, respectively. Thereafter, the electrode body 40 is wrapped in a bag-shaped insulating holder 5. In this manner, a lid assembly 7 consisting of the lid member 30, the terminal members 50, 60, the resin members 70, 80, the electrode body 40, and the insulating holder 5 is formed.

[0031] Next, in the "arrangement step S2" (see FIG. 4), the main body member 20 is prepared, the electrode body 40 covered with the insulating holder 5 of the lid assembly 7 is inserted into the main body member 20, and the lid assembly 7 is arranged on the main body member 20 so that the opening 21 of the main body member 20 is closed with the lid member 30 (see FIG. 6). Specifically, a pair of long side peripheral portions 31b of the peripheral portion 31 of the lid member 30 are opposed to a pair of long side openings 21b of the opening 21 of the main body member 20, respectively, and a pair of short side peripheral portions 31c of the peripheral portion 31 of the lid member 30 are opposed to a pair of short side openings 21c of the opening 21 of the main body member 20, respectively, to close the opening 21 of the main body member 20 with the lid member 30.

[0032] In this case, a peripheral outer surface 31m of the peripheral portion 31 of the cover member 30 facing the outer side DH1 in the cover thickness direction DH (upper side AH1 in the battery height direction AH) is provided in a peripheral high-position region ST located on the outer side DH1 than an opening end surface 21m of the opening 21 of the main body member 20 facing the outer side DH1. Reference form In this case, this high peripheral region ST is provided around the entire periphery of the opening 21 of the main body member 20 and the peripheral portion 31 of the cover member 30. Specifically, by providing the position of the shelf portion 23 (see Figs. 6 and 3(a)) of the main body member 20 that engages the cover member 30 on the outer side DH1 (upper side AH1) than in the past, the entire cover member 30 is disposed on the outer side DH1, and the outer peripheral surface 31m of the peripheral portion 31 of the cover member 30 is disposed on the outer side DH1 of the entire periphery more than the opening end surface 21m of the opening 21 of the main body member 20.

[0033] In addition, instead of providing the shelf portion 23 of the main body member 20 described above on the outer side DH1, the thickness of the cover member 30 may be made thicker than before, so that the entire cover member 30 is positioned on the outer side DH1 and a high peripheral region ST is provided around the entire circumference.

[0034] Next, in the "welding process S3" (see Figure 4), laser light LB is irradiated to the opening 21 of the body member 20 and the peripheral portion 31 of the cover member 30 from the outside DH1 in the lid thickness direction DH of the cover member 30 (the upper side AH1 in the battery height direction AH), and the opening 21 and the peripheral portion 31 are melted and mixed to form a molten metal portion 18Z, which is then solidified to form a molten and solidified portion 18, performing laser welding all around to form the case 10 (see Figures 7(a) and (b)).

[0035] 9(a)(b), in the case where the peripheral outer side surface 31m of the peripheral portion 31 of the cover member 30 and the opening end surface 21m of the opening 21 of the main body member 20 are at the same height (flush) without providing the peripheral high region ST in the arrangement step S2, a part of the molten metal portion 218Z is located on the outer side DH1 in the cover thickness direction DH than the peripheral outer side surface 31m of the cover member 30 (a part of the molten metal portion 218Z is located above the broken line M in FIG. 9(b)), and the molten metal portion 218Z has a shape having a slope 218Zm that becomes lower as it approaches the resin members 70, 80 (to the right in FIG. 9). Therefore, the scattered light LC of the laser light LB irradiated to this slope 218Zm is easily irradiated to the resin members 70, 80, and a burnt portion BP is easily generated in the resin members 70, 80.

[0036] In particular, the resin members 70, 80 provided on the cover member 30 are adjacent to a part of the long side opening 21b of the opening 21 of the main body member 20 (proximal long side opening 21be) and a part of the long side peripheral portion 31b of the peripheral portion 31 of the cover member 30 (proximal long side peripheral portion 31be). For this reason, the peripheral adjacent portions 70e, 80e of the resin members 70, 80 that face and are adjacent to the proximal long side opening 21be of the opening 21 and the proximal long side peripheral portion 31be of the peripheral portion 31 are irradiated with high-intensity scattered light LC, and thus are particularly likely to cause burnt portions BP.

[0037] In response to this, Reference form In (see Figures 7(a) and (b)), the peripheral outer surface 31m of the lid member 30 is located outside DH1 in the lid thickness direction DH relative to the molten metal portion 18Z (the entire molten metal portion 18Z is located below the dashed line M in Figure 7(b)), and the entire molten metal portion 18Z has a shape having a slope 18Zm that becomes lower the further it moves away from the resin members 70, 80 (to the left in Figure 7). For this reason, scattered light LC of the laser light LB irradiated to this slope 18Zm is unlikely to be irradiated onto the resin members 70, 80, thereby preventing the occurrence of burnt areas BP in the resin members 70, 80.

[0038] Next, in a "pouring and sealing process S4", the electrolyte 3 is poured into the case 10 through the pouring hole 30k, and the electrolyte 3 is impregnated into the electrode body 40. Thereafter, the pouring hole 30k is covered from the outside with a sealing member 39, and the sealing member 39 is welded to the lid member 30 around its entire periphery to hermetically seal the gap between the sealing member 39 and the lid member 30. Next, in the "initial charging and aging step S5", a charging device (not shown) is connected to the battery 1 to perform an initial charge on the battery 1. After that, the initially charged battery 1 is left to stand for a predetermined time to age the battery 1. In this way, the battery 1 is completed.

[0039] Books Reference form In the manufacturing method of the battery 1, in the arrangement step S2, the lid assembly 7 is arranged on the body member 20, whereby a peripheral outer surface 31m of the peripheral portion 31 of the lid member 30 is provided in the proximal long side opening 21be and the proximal long side peripheral portion 31be of the opening 21 of the body member 20 and the peripheral portion 31 of the lid member 30, so that the peripheral outer surface 31m of the lid member 30 is located on the outer side DH1 in the lid thickness direction DH than the opening end face 21m of the opening 21 of the body member 20. Then, in the welding step S3, the molten solidified portion 18 is formed so that the peripheral outer surface 31m of the lid member 30 is located on the outer side DH1 than the molten metal portion 18Z (molten solidified portion 18) in the peripheral high position region ST.

[0040] As a result, in the welding step S3, the molten metal portion 18Z formed by irradiating the laser beam LB in the high peripheral region ST has a shape having a slope 18Zm that becomes lower the further away from the resin members 70, 80. Therefore, the scattered light LC of the laser beam LB irradiated to the slope 18Zm is unlikely to be irradiated onto the resin members 70, 80, and scorched portions BP are unlikely to occur in the resin members 70, 80. In particular, scorched portions BP can be prevented from occurring in the peripheral vicinity portions 70e, 80e where scorched portions BP are likely to occur. Furthermore, in the high peripheral region ST, the peripheral outer surface 31m of the cover member 30 is located outer DH1 than the molten solidified portion 18, so water and dust are less likely to accumulate on the cover member 30 (upper case 11) of the battery 1 compared to the comparative embodiment in which a portion of the molten solidified portion (molten metal portion 218Z) is located outer DH1 than the peripheral outer surface 31m of the cover member 30.

[0041] Further books Reference form In the embodiment, the high peripheral region ST is provided around the entire circumference of the opening 21 of the main body member 20 and the peripheral portion 31 of the lid member 30. This makes it possible to prevent scattered light LC from any laser irradiation position from being irradiated onto the resin members 70, 80 during laser welding, thereby preventing the occurrence of scorched areas BP around the entire circumference of the resin members 70, 80. In addition, it is possible to further prevent water and dust from accumulating on the lid member 30 of the battery 1.

[0042] (Implementation state) Next The present invention An embodiment will be described. Reference form The description of the similar parts will be omitted or simplified. Reference form In the manufacturing method of the battery 1, in the arrangement step S2, a peripheral high area ST is provided around the entire circumference of the opening 21 of the main body member 20 and the peripheral portion 31 of the cover member 30, where the peripheral outer surface 31m of the peripheral portion 31 is located on the outer side DH1 of the opening end surface 21m of the opening 21. Attitude The manufacturing method for battery 100 differs in that in the arrangement step S2, a high peripheral region ST is provided only in the opening 121 of body member 120 and a part of the peripheral portion 31 of cover member 30 (proximal long side opening 121be and proximal long side peripheral portion 31be).

[0043] Specifically, in this embodiment In a state teeth, Reference form A body member 120 having an opening 121 with a different shape is used from the body member 20 used in the embodiment (see Figs. 8(a) and 8(b)). In a nutshell The opening 121 of the main body member 120 is a rectangular ring having a pair of long side openings 121b and a pair of short side openings 121c. However, the long side opening 121b has a near long side opening 121be, which is located on the inner side DH2 in the lid thickness direction DH (the lower side AH2 in the battery height direction AH) than other parts 121d of the opening 121 (parts of the long side opening 121b other than the near long side opening 121be and the short side opening 121c) (the opening 121 has four notches).

[0044] This implementation Attitude In the placement process S2, the lid assembly 7 is placed on this main body member 120, so that only in the proximal long side opening 121be and the proximal long side peripheral portion 31be of the opening 121 of the main body member 120 and the peripheral portion 31 of the lid member 30, a peripheral high region ST is formed in which the peripheral outer surface 31m of the peripheral portion 31 is located outer DH1 than the opening end face 121m of the opening 121.

[0045] Thereafter, in a welding step S3, the opening 121 of the main body member 120 and the peripheral portion 31 of the cover member 30 are laser-welded to each other, so that in the peripheral high-level region ST, Reference form As explained in (see FIG. 7), the peripheral outer surface 31m of the lid member 30 is located on the outer side DH1 in the lid thickness direction DH than the molten metal portion 18Z, and the molten metal portion 18Z has a shape having a slope 18Zm that becomes lower the further it is from the resin members 70, 80. Therefore, the scattered light LC of the laser light LB irradiated to this slope 18Zm is unlikely to be irradiated to the peripheral adjacent portions 70e, 80e of the resin members 70, 80, so that the generation of scorched portions BP in the peripheral adjacent portions 70e, 80e can be suppressed.

[0046] On the other hand, in the opening 121 of the main body member 120 and the peripheral portion 31 of the lid member 30, in the portion where the high peripheral region ST is not provided, as described in the comparative embodiment (see FIG. 9), a part of the molten metal portion 218Z is located on the outer side DH1 in the lid thickness direction DH than the peripheral outer side surface 31m of the lid member 30, and the molten metal portion 218Z has a shape having a slope 218Zm that becomes lower as it approaches the resin members 70, 80, so that the scattered light LC of the laser light LB irradiated to this slope 218Zm is easily irradiated to the resin members 70, 80. However, in the portion where the high peripheral region ST is not provided, the distance from the opening 121 and the peripheral portion 31 to the resin members 70, 80 is sufficiently long. Therefore, the high-intensity scattered light LC is not irradiated to the resin members 70, 80, and the burnt portion BP is unlikely to occur in the resin members 70, 80.

[0047] This implementation AttitudeIn the manufacturing method of the battery 100, in the arrangement step S2, the peripheral outer surface 31m of the peripheral portion 31 of the cover member 30 is arranged so that the peripheral high-position region ST located on the outer side DH1 of the opening end surface 121m of the opening 121 of the main body member 120 is arranged so as to be located on the adjacent long side opening of the opening 121 and the peripheral portion 31. 121be and adjacent long side peripheral portion 31be. Therefore, in this high peripheral region ST, the scattered light LC of the laser light LB is unlikely to be irradiated onto the resin members 70, 80, and burnt portions BP are unlikely to occur in the resin members 70, 80. In particular, the generation of burnt portions BP can be suppressed in the peripheral adjacent portions 70e, 80e where burnt portions BP are likely to occur. In addition, in the high peripheral region ST, the peripheral outer surface 31m of the lid member 30 is located on the outer side DH1 of the melt-solidified portion 18, so that water and dust are unlikely to accumulate on the lid member 30 of the battery 100.

[0048] In addition, this embodiment In a state Since the main body member 120 is configured such that the proximal long side opening 121be of the opening 121 is located on the inner side DH2 in the lid thickness direction DH than the other portion 121d of the opening 121, when the lid assembly 7 is arranged in the arrangement step S2, the peripheral high area ST can be easily provided in the proximal long side opening 121be of the opening 121 and the proximal long side peripheral portion 31be of the peripheral portion 31. Reference form The similar part is, Reference form It has the same effect as the above.

[0049] The above is an embodiment of the present invention. In a nutshell Although the present invention has been described above with reference to the embodiment, In a nutshell It goes without saying that the present invention is not limited to the above and can be modified as appropriate without departing from the spirit of the present invention. For example, In a state Although a laminated electrode body 40 has been exemplified as the electrode body housed in the case 10, the electrode body may be a flat wound electrode body. Also, a plurality of electrode bodies may be housed in the case. [Explanation of symbols]

[0050] 1,100 Batteries (energy storage devices) 7 Lid Assembly 10 Cases 18 Melting and solidification section 20,120 Body material 21,121 Openings 21m,121m Open end surface 21b,121b Long side opening 21be, 121be Near long side opening 21c,121c Short side opening 121d Other parts 30 Lid member 31 Periphery 31m outer perimeter 31b Long side edge 31be Near long edge 31c Short side edge 33, 34 Surroundings of insertion hole 33h, 34h Insertion holes 40 Electrode body 50,60 Terminal material 70,80 Resin material 70e, 80e (of resin parts) near the periphery DH Lid thickness direction DH1 (lid thickness direction) outside DH2 (inside of the lid) LB laser light LC scattered light High ST margins S1 Lid assembly forming process S2 placement process S3 Welding process S4 Liquid injection / sealing process S5 First charge and aging process

Claims

1. A cylindrical main body member having a bottom and a rectangular annular opening having a pair of long side openings and a pair of short side openings; a cover member having a rectangular annular peripheral portion that is laser welded to the main body member over the entire periphery in a manner to close the opening, the cover member having a pair of long side peripheral portions and a pair of short side peripheral portions; Case and a terminal member inserted into an insertion hole passing through the cover member in a thickness direction of the cover; a resin member bonded to the insertion hole surrounding portion of the cover member and the terminal member while insulating the insertion hole surrounding portion of the cover member and the terminal member. A method for manufacturing an electricity storage device, comprising: a positioning step of positioning the lid assembly obtained by integrating the terminal member with the lid member via the resin member such that the pair of long side peripheral portions of the lid member face the pair of long side openings of the main body member and the pair of short side peripheral portions of the lid member face the pair of short side openings of the main body member, respectively, so as to close the openings of the main body member with the lid member; a welding process for forming the case by irradiating the lid member with a laser beam from the outside in the lid thickness direction, melting and mixing the opening of the main body member and the peripheral edge of the lid member, and then solidifying the melted and solidified portion over the entire periphery, The above-mentioned arrangement step includes: A peripheral high-level region in which a peripheral outer surface of the peripheral portion of the cover member facing outward is located outside of an opening end surface of the opening of the main body member facing outward, Among the openings and the peripheral portions, at least one of the pair of long side openings that is adjacent to the resin member and one of the pair of long side peripheral portions that is adjacent to the resin member are provided, The above welding process is In the high peripheral region, the melt-solidified portion is formed in a manner that the outer peripheral surface of the cover member is located outside the melt-solidified portion, The opening in the body member is The adjacent long side opening is located more inward in the thickness direction of the lid than other portions of the opening. A method for manufacturing an electricity storage device.

2. A cylindrical main body member having a bottom and a rectangular annular opening having a pair of long side openings and a pair of short side openings; a cover member having a rectangular annular peripheral portion that is laser welded to the main body member over the entire periphery in a manner to close the opening, the cover member having a pair of long side peripheral portions and a pair of short side peripheral portions; Case and a terminal member inserted into an insertion hole passing through the cover member in a thickness direction of the cover; a resin member bonded to the insertion hole surrounding portion of the cover member and the terminal member while insulating the insertion hole surrounding portion of the cover member and the terminal member. An electricity storage device, At least one of the opening of the main body member and the peripheral edge of the lid member Regarding a proximate long side opening portion of the pair of long side openings that is proximate to the resin member, and a proximate long side peripheral portion that faces the proximate long side opening portion and is proximate to the resin member of the pair of long side peripheral portions, The outer peripheral surface of the peripheral portion facing outward in the thickness direction of the lid is located outside of a melted and solidified portion formed after the opening and the peripheral portion are melted and mixed and then solidified, The opening in the body member is The adjacent long side opening is located more inward in the thickness direction of the lid than other portions of the opening. Energy storage device.

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