Power storage device and method for manufacturing power storage device

Abstract

The present invention provides an electricity storage device and a method for manufacturing the same, in which a resin convex part is firmly and integrally arranged on the inner side of a metal case member, and even if an electrode body is broken, the safety valve can be prevented from being blocked from the inner side by fragments of the electrode body, so that the safety valve can properly function. A power storage device (1) is provided with a relief valve (30) in a metal case member (21). The housing member has a valve periphery roughened portion (24) around the safety valve in a housing inner surface (23). The power storage device is further provided with a resin protrusion (40) for suppressing the clogging of the safety valve by fragments of the electrode body (50), the resin protrusion (40) being joined to the valve periphery roughened section and protruding toward the inside EH. Nanopillars (26) are erected on the valve periphery roughened portion, and the clogging suppression resin convex portion is joined to the valve periphery roughened portion by filling a resin material (45) between the erected nanopillars.

Description

Technical Field

[0001] The present invention relates to a power storage device having a safety valve provided in a housing member constituting a housing, and a method for manufacturing the power storage device. Background Art

[0002] As a power storage device, a battery is known in which an electrode body is housed in a metal housing and a safety valve is provided in a housing member forming the housing. The safety valve opens when the internal pressure of the housing exceeds the opening pressure, and discharges gas to the outside. For example, such a battery is disclosed in Patent Document 1 (see Figure 1 and Figure 2 etc.).

[0003] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2017 - 117750

[0004] However, when a nail penetration test is performed on such a battery, there is a case where the temperature of the electrode body rises rapidly and a part of the electrode body breaks. If the broken fragments of the electrode body further move to the vicinity of the safety valve and block the safety valve from the inside, it may prevent the opening of the safety valve or the discharge of gas through the opened safety valve.

[0005] Therefore, in order to solve this problem, the present inventors have conceived to integrally provide a convex portion protruding inward with the housing member around the safety valve on the inner side surface of the housing of the housing member provided with the safety valve, thereby suppressing the broken fragments of the electrode body from blocking the safety valve from the inside.

[0006] However, (1) in the case of stamping the housing member to make a part of the housing member a metal convex portion, especially when making the thickness of the housing member thicker, if it is desired to increase or enlarge the convex portion, it is sometimes impossible to form the metal convex portion into a desired shape in the stamping process. In addition, there are also problems such as strain deformation easily occurring in the housing member during stamping and leakage easily occurring during the subsequent sealing of the housing. (2) On the other hand, a separately formed metal convex portion can be welded to the housing member. In this case, there are also problems such as the housing member being easily deformed during welding, and the cost increases. (3) Or, a housing member having a metal convex portion is formed by casting, but its productivity is low and the cost increases. Summary of the Invention

[0007] The present invention has been made in view of this situation, and provides a power storage device and a method for manufacturing the power storage device, which use a housing member in which a resin convex portion is firmly integrally provided inside a metal housing member instead of a metal convex portion, so that even when the electrode body breaks, it is possible to suppress the broken fragments of the electrode body from blocking the safety valve from the inside, thereby enabling the safety valve to function properly. (1)

[0009] One aspect of the present invention for solving the above problems is a power storage device as follows: The power storage device includes: a housing having a metal housing member; a safety valve provided on the housing member; and an electrode body housed in the housing. The power storage device is characterized in that the housing member has a roughened valve surrounding roughened portion around the safety valve on the inner side surface of the inner housing, and the power storage device further includes a clogging suppression resin protrusion which is a resin protrusion that engages with the valve surrounding roughened portion of the inner side surface of the housing and protrudes inward. In the case where the electrode body breaks, the clogging suppression resin protrusion suppresses the fragments of the electrode body from clogging the safety valve from the inside. Nanopillars are erected on the valve surrounding roughened portion, and the nanopillars are formed by beaded bonding of particles of the metal forming the housing member into a column shape and have a height of 50 nm or more. The clogging suppression resin protrusion engages with the valve surrounding roughened portion by filling the resin material for forming the clogging suppression resin protrusion between the erected nanopillars.

[0010] In the above power storage device, the clogging suppression resin protrusion is provided around the safety valve on the inner side surface of the housing member of the housing. Therefore, even in the case where the electrode body breaks due to a nail penetration test or the like, it is possible to suppress the fragments of the broken electrode body from clogging the safety valve from the inside, so that the safety valve can open properly, and the gas can be properly discharged to the outside through the opened safety valve. Further, a nanoscale (nanometer level) valve surrounding roughened portion with the above nanopillars erected is provided on the inner side surface of the housing member of the housing, and the resin material is filled between the erected nanopillars, thereby joining the clogging suppression resin protrusion to the valve surrounding roughened portion. Therefore, the joining strength between the housing member and the clogging suppression resin protrusion can be improved.

[0011] In addition, examples of the "power storage device" include secondary batteries such as lithium ion secondary batteries, sodium ion secondary batteries, calcium ion secondary batteries, and capacitors such as lithium ion capacitors.

[0012] The "safety valve" can be a non - reset type safety valve that breaks and opens itself when the internal pressure of the housing exceeds the opening pressure, or a reset type safety valve that opens when the internal pressure of the housing exceeds the opening pressure and closes when the internal pressure of the housing is lower than the opening pressure. In addition, the safety valve can also be a temperature - open type safety valve that opens when the safety valve exceeds a specified temperature.

[0013] As the form of the "clogging prevention resin convex part", when the housing member is in a form extending in the long-side direction, a pair of clogging prevention resin convex parts are provided on both sides of the long-side direction around the safety valve, or a pair of clogging prevention resin convex parts are provided on both sides of the short-side direction around the safety valve. In addition, as the form of the clogging prevention resin convex part, a form is also given in which a plurality of clogging prevention resin convex parts are provided around the safety valve in a manner that surrounds the entire safety valve. (2)

[0015] In addition, another embodiment is a method for manufacturing an electrical storage device, wherein the electrical storage device comprises: a shell having a metal shell component; a safety valve, which is arranged on the shell component; and an electrode body, which is accommodated in the shell, and the shell component has a roughened valve surrounding roughened portion around the safety valve on the inner side surface of the shell located inside, and the electrical storage device further comprises a clogging inhibition resin protrusion, which is a resin protrusion that is joined to the valve surrounding roughened portion on the inner side surface of the shell and protrudes to the inner side, and when the electrode body is broken, the clogging inhibition resin protrusion inhibits fragments of the electrode body from clogging the safety valve from the inner side, and the valve surrounding roughened portion There are a forest of nanocolumns, and the nanocolumns are formed by particles from the metal forming the shell part being connected in a beaded manner to form a columnar shape, and the height is greater than 50nm. The clogging inhibition resin protrusion is joined to the roughened portion around the valve by filling the resin material forming the clogging inhibition resin protrusion between the nanocolumns standing in the forest, and the manufacturing method of the above-mentioned power storage device comprises: a shell roughening step, in which a pulsed laser is intermittently irradiated to the inner side surface of the shell of the shell part in a staggered irradiation position, thereby forming the roughened portion around the valve where the nanocolumns stand in a forest; and a resin molding step, in which the resin material is filled between the nanocolumns standing in the roughened portion around the valve, and the clogging inhibition resin protrusion is molded.

[0016] In the above-mentioned method for manufacturing an electric storage device, in the case roughening step, a pulsed laser is irradiated onto the case inner side surface of the case member as described above to form a nanoscale valve surrounding roughening portion in which nanopillars are arranged in a forest, so that the valve surrounding roughening portion can be easily provided on the case inner side surface. Furthermore, in the resin molding step, a resin material is filled between the nanopillars arranged in the valve surrounding roughening portion, and a clogging-inhibiting resin convex portion is molded, so that a clogging-inhibiting resin convex portion firmly bonded to the valve surrounding roughening portion can be provided. (3)

[0018] Further, the manufacturing method of the power storage device described in (2) may be as follows: The housing member has insertion through-holes, and the power storage device further includes: a terminal member inserted into the insertion through-holes of the housing member; and a terminal resin member that insulates between the housing member and the terminal member and is joined to the housing member and the terminal member to fix the terminal member to the housing member. In the resin molding process, with the terminal member inserted into the insertion through-holes of the housing member, the terminal resin member joined to the housing member and the terminal member is molded, and the clogging suppression resin protrusion joined to the housing member is molded.

[0019] In a power storage device having a terminal resin member that fixes a terminal member to a housing member, the terminal resin member and the clogging suppression resin protrusion can be molded separately. In contrast, in the manufacturing method of the above-described power storage device, the terminal resin member and the clogging suppression resin protrusion are molded at once, so that the terminal resin member and the clogging suppression resin protrusion can be provided easily and inexpensively. Further, the terminal resin member and the clogging suppression resin protrusion may be molded using the same resin material or may be molded using different resin materials separately. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a perspective view of the battery according to Embodiment 1.

[0021] Figure 2 is a partial cross-sectional view of the battery according to Embodiment 1 along the battery height direction and the battery width direction.

[0022] Figure 3 is a top view of the vicinity of the safety valve of the battery according to Embodiment 1 as viewed from the inside of the housing cover member.

[0023] Figure 4 is of the vicinity of the safety valve of the battery according to Embodiment 1 Figure 3 sectional view taken along line A - A in

[0024] Figure 5 Regarding Embodiment 1, it is a partial enlarged cross-sectional view that magnifies the joint portion between the valve peripheral roughened portion and the like on the inner side of the housing of the housing cover member and the clogging suppression resin protrusion and the like.

[0025] Figure 6 is a flowchart of the manufacturing method of the battery according to Embodiment 1.

[0026] Figure 7Regarding the manufacturing method of the battery according to Embodiment 1, it is an explanatory diagram showing a case where pulsed laser is scanned in the housing roughening process (or terminal roughening process) to form a plurality of bowl-shaped recesses and nanocolumns standing in the bowl-shaped recesses.

[0027] Figure 8 Regarding the manufacturing method of the battery according to Embodiment 1, it is an explanatory diagram showing a case where positive and negative terminal components are respectively inserted into the insertion through holes in the housing cover component in the resin molding process.

[0028] Figure 9 Regarding the manufacturing method of the battery according to Embodiment 1, it is an explanatory diagram showing a case where a pair of terminal resin components and a pair of blockage suppression resin protrusions are formed in the resin molding process.

[0029] Figure 10 It is a top view observed from the inside of the housing cover component near the safety valve of the battery according to Embodiment 2.

[0030] Figure 11 It is near the safety valve of the battery according to Embodiment 2, Figure 10 a cross-sectional view taken along line B - B in

[0031] Figure 12 It is a top view observed from the inside of the housing cover component near the safety valve of the battery according to Embodiment 3.

[0032] Figure 13 It is near the safety valve of the battery according to Embodiment 3, Figure 12 a cross-sectional view taken along line C - C in

[0033] Explanation of reference numerals:

[0034] 1, 100, 200... battery (power storage device); 10... housing; 21... housing cover component (housing component); 21Z... (before roughening) housing cover component; 21h... insertion through hole; 23... inner side surface of the housing of the (housing cover component); 24, 124, 224... valve surrounding roughening part on the (inner side surface of the housing); 26... nanocolumn; 26p... particle; 30... safety valve; 40, 140, 240... blockage suppression resin protrusion; 45... resin material for forming the blockage suppression resin protrusion; 50... electrode body; 60... terminal component; 60Z... (before roughening) terminal component; 70... terminal resin component; 75... resin material for forming the terminal resin component; DH... outside of the (housing cover component); EH... inside of the (housing cover component); LB... pulsed laser; S1... housing roughening process; S2... terminal roughening process; S3... resin molding process. Detailed description of the embodiments

[0035] (Embodiment 1)

[0036] Hereinafter, a first embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1 A perspective view showing the battery (an example of the power storage device of the present invention) 1 of the present Embodiment 1, Figure 2 A partial cross-sectional view showing the battery 1. In addition, Figure 3 A plan view seen from the inside EH of the vicinity of the safety valve 30 in the battery 1, Figure 4 Showing Figure 3 A cross-sectional view taken along the line A - A in Figure 5 In addition, a partial enlarged cross-sectional view showing the joint portion of the valve peripheral roughened portion 24 and the clogging suppression resin convex portion 40 on the inner side surface 23 of the housing of the housing lid member 21. Hereinafter, the battery height direction AH, the battery width direction BH, and the battery thickness direction CH of the battery 1 are defined as Figure 1 And Figure 2 The directions shown will be described.

[0037] The battery 1 is a square (rectangular parallelepiped shape) and sealed lithium-ion secondary battery mounted on vehicles such as hybrid vehicles, plug-in hybrid vehicles, and electric vehicles. The battery 1 includes a metal housing 10 provided with a safety valve 30, an electrode body 50 housed in the housing 10, an electrolytic solution 5, and positive and negative terminal members 60 respectively fixed to the housing 10 via terminal resin members 70. The electrode body 50 is insulated and held by an insulating member 7 in the housing 10. The insulating member 7 is made of an insulating film and is in the shape of a bag opening upward in the battery height direction AH.

[0038] Among them, the electrode body 50 is in the shape of a rectangular parallelepiped and is a stacked type, and is formed by alternately stacking a plurality of rectangular positive electrode plates 51 and a plurality of rectangular negative electrode plates 52 in the battery thickness direction CH via a rectangular separator 53 made of a porous resin film. On one side BH1 in the battery width direction BH of the electrode body 50, the current collector foils of the respective positive electrode plates 51 overlap in the battery thickness direction CH to form a positive current collector portion 50c. The positive current collector portion 50c is conductively connected to the positive terminal member 60. In addition, on the other side BH2 in the battery width direction BH of the electrode body 50, the current collector foils of the respective negative electrode plates 52 overlap in the battery thickness direction CH to form a negative current collector portion 50d. The negative current collector portion 50d is conductively connected to the negative terminal member 60.

[0039] The housing 10 is a rectangular parallelepiped box made of metal (aluminum in the present Embodiment 1), having a bottomed square tube shape with a rectangular opening 11c, and is composed of a housing main body member 11 that houses the electrode body 50 inside, and a rectangular plate-shaped housing cover member 21 that closes the opening 11c of the housing main body member 11. In the present Embodiment 1, the housing cover member 21 corresponds to the above-mentioned "housing member", and the housing cover member 21 has two main surfaces, namely, a housing outer side surface 22 facing the outside DH (upper side AH1) and a housing inner side surface 23 facing the inside EH (lower side AH2 in the battery height direction AH). The opening 11c of the housing main body member 11 and the peripheral portion 21f of the housing cover member 21 are hermetically welded over the entire circumference. A liquid injection hole 21k is provided in the housing cover member 21, and the liquid injection hole 21k is hermetically sealed by a disc-shaped sealing member 15 made of aluminum.

[0040] The safety valve 30 is integrally formed with the housing cover member 21 in the housing 10 (a part of the housing cover member 21 forms the safety valve 30). The safety valve 30 is elliptical in plan view (elliptical when viewed from the upper side AH1), has a plate shape thinner than the thickness of the housing cover member 21, and a fracture predetermined portion 31 formed by a V-shaped groove is formed in a specified shape on the outside DH (upper side AH1). The dimension in the long side direction (battery width direction BH) of the safety valve 30 is 15 mm, and the dimension in the short side direction (battery thickness direction CH) is 5 mm. When the internal pressure of the housing 10 exceeds the opening pressure, the fracture predetermined portion 31 of the safety valve 30 fractures and the valve opens. Then, the gas inside the housing 10 is released to the outside of the housing 10 through the fractured safety valve 30.

[0041] A clogging suppression resin protrusion 40 is joined around the safety valve 30 on the housing inner side surface 23 of the housing cover member 21 (refer to Figure 3 , Figure 4 and Figure 2 ). Specifically, the housing inner side surface 23 of the housing cover member 21 has a pair of valve-peripheral roughened portions 24 roughened around the safety valve 30. These valve-peripheral roughened portions 24 are respectively provided on one side BH1 and the other side BH2 in the long side direction (battery width direction BH) of the housing cover member 21 around the safety valve 30 on the housing inner side surface 23 in a form extending substantially along the short side direction (battery thickness direction CH) of the housing cover member 21.

[0042] Each valve-peripheral roughened portion 24 is subjected to a roughening treatment based on a pulsed laser LB described later and becomes a nanoscale nano-roughened portion. Specifically, in the valve-peripheral roughened portion 24, a plurality of bowl-shaped recesses 25 having a diameter Da of 30 to 300 μm (substantially Da = 80 μm in the present Embodiment 1) in the shape of a bowl or an arc pit are arranged and configured in a partially overlapping manner (refer toFigure 7 )。In these bowl-shaped recesses 25, nanoparticles 26p made of the metal forming the housing lid member 21 stand upright and are joined in a beaded shape to form nanocolumns 26 having a column height ha of 50 nm or more (in the present Embodiment 1, the approximate height is ha = 200 nm) (see Figure 5 and Figure 7 ). The metal forming the housing lid member 21 is aluminum as described above, and the nanocolumns 26 are formed by particles 26p composed of aluminum and aluminum oxide.

[0043] On a pair of valve peripheral roughened portions 24 on the inner side surface 23 of the housing, resin convex portions, i.e., blockage suppression resin convex portions 40, protruding inwardly EH are respectively joined. That is, the two blockage suppression resin convex portions 40 extend substantially along the short side direction (battery thickness direction CH) of the housing lid member 21 on one side BH1 and the other side BH2 in the long side direction (battery width direction BH) of the housing lid member 21 around the safety valve 30, and protrude inwardly EH respectively. By providing such blockage suppression resin convex portions 40, even when a part of the electrode body 50 breaks and the broken fragments of the electrode body 50 move near the safety valve 30, the blockage suppression resin convex portions 40 abut against the fragments of the electrode body 50, and it is possible to suppress the situation where the fragments of the electrode body 50 block the safety valve 30 from the inner side EH to the outer side DH.

[0044] The height hb of the blockage suppression resin convex portion 40 is preferably in the range of 1.0 to 5.0 mm. In the present Embodiment 1, the height hb = 2.0 mm. By making the height hb of the blockage suppression resin convex portion 40 1.0 mm or more (hb ≥ 1.0 mm), it is possible to more effectively suppress the blockage of the safety valve 30 by the fragments of the electrode body 50. On the other hand, by limiting the height hb of the blockage suppression resin convex portion 40 to 5.0 mm or less (hb ≤ 5.0 mm), the distance from the inner side surface 23 of the housing to the electrode body 50 can be shortened (space reduced), and a larger electrode body 50 can be accommodated in the housing 10. Therefore, the battery capacity per unit volume of the battery 1 can be increased.

[0045] The blockage suppression resin convex portion 40 is composed of a resin material 45 containing a thermoplastic main resin (polyphenylene sulfide (PPS) in the present Embodiment 1), a thermoplastic elastomer (thermoplastic polyurethane elastomer in the present Embodiment 1), and a filler (fibrous glass filler in the present Embodiment 1). The blockage suppression resin convex portion 40 is joined to the valve peripheral roughened portion 24 with a strong bonding force by filling the resin material 45 between the nanocolumns 26 standing on the valve peripheral roughened portion 24 on the inner side surface 23 of the housing.

[0046] Next, the relationship between the housing lid member 21 and the terminal member 60 and the terminal resin member 70 will be described (seeFigure 1 and Figure 2 )。In the vicinity of the ends on one side BH1 and the other side BH2 in the battery width direction BH of the case lid member 21, rectangular insertion holes 21h are respectively provided. In the insertion hole 21h on one side BH1, a terminal member 60 of the positive electrode made of aluminum is inserted. A terminal resin member 70 of the positive electrode insulates between the case lid member 21 and the terminal member 60, and is hermetically and firmly joined to the case lid member 21 and the terminal member 60, thereby fixing the terminal member 60 to the case lid member 21. In the insertion hole 21h on the other side BH2, a terminal member 60 of the negative electrode made of copper is inserted. A terminal resin member 70 of the negative electrode insulates between the case lid member 21 and the terminal member 60, and is hermetically and firmly joined to the case lid member 21 and the terminal member 60, thereby fixing the terminal member 60 to the case lid member 21. The positive and negative terminal members 60 have the same shape, and in addition, the positive and negative terminal resin members 70 also have the same shape. Therefore, the following description will be concentrated.

[0047] Each terminal member 60 is formed by stamping a metal plate (aluminum plate for the positive electrode and copper plate for the negative electrode). The terminal member 60 is composed of a rectangular plate-shaped terminal top plate portion 60a located outside the case lid member 21 (upper side AH1) and extending in the battery width direction BH and the battery thickness direction CH, and a terminal protruding portion 60b extending from the terminal top plate portion 60a to the inside EH (lower side AH2) of the case lid member 21. The terminal protruding portion 60b is bent at the end on one side CH1 in the battery thickness direction CH of the terminal top plate portion 60a and extends downward to the lower side AH2, and further penetrates the terminal resin member 70 in the insertion hole 21h of the case lid member 21 and extends downward to the lower side AH2. The front end portion of the positive terminal protruding portion 60b on the lower side AH2 is welded to the positive current collecting portion 50c of the electrode body 50. On the other hand, the front end portion of the negative terminal protruding portion 60b on the lower side AH2 is welded to the negative current collecting portion 50d of the electrode body 50.

[0048] A terminal resin member 70 is joined near the insertion hole 21h on the terminal surface 61 of the terminal member 60. Specifically, the terminal surface 61 has a roughened terminal roughened portion 62 near the insertion hole 21h. This terminal roughened portion 62 is the same as the valve peripheral roughened portion 24 of the above-described case lid member 21 and becomes a nano-level nano-roughened portion. That is, a plurality of bowl-shaped recesses 63 are arranged in the terminal roughened portion 62 (refer to Figure 7 ), and in each bowl-shaped recess 63, nano-columns 64 in which particles 64p made of the metal forming the terminal member 60 are joined in a bead shape and become columnar with a height ha of 50 nm or more (in the present Embodiment 1, the height is approximately ha = 200 nm) stand (refer to Figure 5 and Figure 7)。The metal of the terminal component 60 forming the positive electrode is aluminum as described above, and the nanocolumns 64 of the positive electrode are formed by particles 64p composed of aluminum and aluminum oxide. On the other hand, the metal of the terminal component 60 forming the negative electrode is copper as described above, and the nanocolumns 64 of the negative electrode are formed by particles 64p composed of copper and copper oxide.

[0049] In addition, a terminal resin component 70 is also joined near the insertion through-hole 21h in the housing cover component 21. Specifically, the housing cover component 21 has a roughened portion near the hole 27 near the insertion through-hole 21h. The roughened portion near the hole 27 is the same as the roughened portion around the valve 24 of the housing cover component 21 and the terminal roughened portion 62 of the terminal component 60, and becomes a nanoscale nanoroughness portion. That is, the roughened portion near the hole 27 has a plurality of bowl-shaped recesses 28 (refer to Figure 7 ), and nanocolumns 29 with a columnar height ha of 50 nm or more (in the first embodiment, the height is approximately ha = 200 nm) formed by the combination of particles 29p made of the metal forming the housing cover component 21 (specifically aluminum) stand in each bowl-shaped recess 28 (refer to Figure 5 and Figure 7 ).

[0050] The terminal resin component 70 is different from the resin material 45 forming the clogging suppression resin protrusion 40, and is composed of a resin material 75 including a thermoplastic main resin (perfluoroalkoxy alkane (PFA) in the first embodiment), a thermoplastic elastomer (thermoplastic polyurethane elastomer in the first embodiment), and a filler (fibrous glass filler in the first embodiment). The terminal resin component 70 is hermetically joined to the terminal roughened portion 62 with a strong bonding force by filling the resin material 75 between the nanocolumns 64 standing in the terminal roughened portion 62 of the terminal component 60, and is hermetically joined to the roughened portion near the hole 27 of the housing cover component 21 with a strong bonding force by filling the resin material 75 between the nanocolumns 29 standing in the roughened portion near the hole 27 of the housing cover component 21.

[0051] In the battery 1 of the present Embodiment 1, a clogging suppression resin protrusion 40 is provided around the safety valve 30 on the inner surface 23 of the housing of the housing cover member 21. Therefore, even if the electrode body 50 breaks due to a nail penetration test or the like, it is possible to suppress the fragments of the broken electrode body 50 from clogging the safety valve 30 from the inner side EH to the outer side DH, so that the safety valve 30 can open properly, and the gas can be properly discharged to the outside through the opened safety valve 30. Further, on the inner surface 23 of the housing of the housing cover member 21, a valve periphery roughened portion 24 with nanoscale pillars 26 standing is provided, and a resin material 45 is filled between the standing nanoscale pillars 26, so that the clogging suppression resin protrusion 40 is joined to the valve periphery roughened portion 24. Therefore, the joining strength between the housing cover member 21 and the clogging suppression resin protrusion 40 can be improved.

[0052] Next, a method for manufacturing the above-described battery 1 will be described (refer to Figures 6 - 9 ). First, a housing cover member 21Z before roughening is prepared. The housing cover member 21Z before roughening is obtained by stamping an aluminum plate. Further, through this stamping process, the safety valve 30 is also formed in the housing cover member 21Z. In addition, a terminal member 60Z before roughening is prepared. The terminal member 60Z before roughening is obtained by stamping a metal plate (aluminum plate for the positive electrode and copper plate for the negative electrode).

[0053] Then, in a housing roughening step S1 (refer to Figure 6 ), the pulsed laser LB is intermittently irradiated on a predetermined portion around the safety valve 30 on the inner surface 23 of the housing of the above-described housing cover member 21Z in a manner of staggering the irradiation positions, so as to form a pair of valve periphery roughened portions 24 in which a plurality of bowl-shaped recesses 25 are arranged in a partially overlapping manner (refer to Figure 7 ). In addition, the pulsed laser LB is intermittently irradiated on predetermined portions near a pair of insertion holes 21h in the housing cover member 21Z in a manner of staggering the irradiation positions, so as to form a pair of hole periphery roughened portions 27 in which a plurality of bowl-shaped recesses 28 are arranged in a partially overlapping manner. Further, the irradiation conditions of the laser are as follows: the wavelength is 1064 nm, the peak output is 5 kW, the pulse width is 150 ns, the pitch pb is 75 μm, and the spot diameter Da is 80 μm.

[0054] In the portion of the housing cover member 21Z irradiated with the pulsed laser LB, the metal near the surface (specifically aluminum) is melted and further becomes vapor. Then, when the temperature of the vapor decreases, it becomes particles 26p and 29p of aluminum and aluminum oxide and accumulates in the bowl-shaped recesses 25 and 28. By intermittently irradiating the pulsed laser LB in a manner of staggering the irradiation positions, the particles 26p and 29p are stacked in a bead shape and combined into columns, thereby forming standing nanoscale pillars 26 and 29 (refer to Figure 7 andFigure 5 )。

[0055] And, in another terminal roughening process S2 (refer to Figure 6 ), the pulsed laser LB is intermittently irradiated onto the specified parts of the positive and negative terminal components 60Z in a manner that the irradiation positions are staggered, thereby forming a terminal roughening portion 62 in which a plurality of bowl-shaped recesses 63 are arranged in a partially overlapping manner (refer to Figure 7 ). In each bowl-shaped recess 63, particles 64p (aluminum and alumina particles for the positive electrode, copper and copper oxide particles for the negative electrode) stand upright and are stacked and combined in a bead-like shape to form a columnar nanocolumn 64 (refer to Figure 7 and Figure 5 ). In addition, the irradiation conditions of the laser on the positive terminal component 60 are the same as those in the housing roughening process S1. On the other hand, the irradiation conditions of the laser on the negative terminal component 60 are as follows: the wavelength is 1064 nm, the peak output is 20 kW, the pulse width is 50 ns, the pitch pb is 60 μm, and the spot diameter Da is 75 μm.

[0056] Next, in the resin molding process S3 (refer to Figure 6 ), in a state where the positive and negative terminal components 60 are inserted through a pair of insertion holes 21h of the housing cover component 21, a pair of terminal resin components 70 that are joined to the housing cover component 21 and the terminal components 60 are molded, and a pair of clogging suppression resin protrusions 40 that are joined to the housing cover component 21 are molded (refer to Figure 8 and Figure 9 ).

[0057] Specifically, this resin molding process S3 is performed using a molding die (not shown) having an upper die and a lower die. First, the housing cover component 21 is arranged at a specified position of the lower die, and further, the positive and negative terminal components 60 are respectively inserted through a pair of insertion holes 21h of the housing cover component 21 (refer to Figure 8 ). After that, the upper die is moved toward the lower die to close the molding die.

[0058] Next, the molten resin formed by melting the resin material 75 is respectively injected into two cavities for forming the terminal resin member 70, and the molten resin formed by melting the resin material 45 is respectively injected into two cavities for forming the clogging suppression resin protrusion 40. At this time, the molten resin of the resin material 75 is also filled between the nano-columns 29 standing in the roughened portion 27 near the hole of the housing lid member 21 and between the nano-columns 64 standing in the terminal roughened portion 62 of the terminal member 60. In addition, the molten resin of the resin material 45 is also filled between the nano-columns 26 standing in the valve surrounding roughened portion 24 of the housing lid member 21. Then, a pair of terminal resin members 70 firmly and airtightly joined to the roughened portion 27 near the hole of the housing lid member 21 and the terminal roughened portion 62 of the terminal member 60 are insert-molded. In addition, along with this, a pair of clogging suppression resin protrusions 40 firmly joined to the valve surrounding roughened portion 24 of the housing lid member 21 are insert-molded (refer to Figure 9 ). After that, the lid assembly 17 obtained by molding the terminal resin member 70 and the clogging suppression resin protrusion 40 is taken out from the molding die.

[0059] Next, in the electrode body connection process S4 (refer to Figure 6 ), an electrode body 50 obtained by laminating a positive electrode plate 51, a negative electrode plate 52, and a separator 53 is prepared, and the terminal protrusion 60b of the positive terminal member 60 in the lid assembly 17 is ultrasonically welded to the positive current collector portion 50c of the electrode body 50. In addition, the terminal protrusion 60b of the negative terminal member 60 in the lid assembly 17 is ultrasonically welded to the negative current collector portion 50d of the electrode body 50. After that, the electrode body 50 is wrapped with a bag-shaped insulating holding member 7.

[0060] Next, in the electrode body housing and housing forming process S5, a housing main body member 11 is prepared, the electrode body 50 covered with the insulating holding member 7 is inserted into the housing main body member 11, and the opening 11c of the housing main body member 11 is blocked by the housing lid member 21. Then, the opening 11c of the housing main body member 11 and the peripheral portion 21f of the housing lid member 21 are hermetically laser welded over the entire circumference to form a housing 10 that houses the electrode body 50 inside.

[0061] Next, in the liquid injection and sealing process S6, after inserting the liquid injection nozzle of a liquid injection device (not shown) into the liquid injection hole 21k, the electrolyte 5 is ejected from the front end of the liquid injection nozzle inside the housing 10, the electrolyte 5 is injected into the housing 10, and further the electrolyte 5 is allowed to penetrate into the electrode body 50. After that, the liquid injection hole 21k is covered from the outside with a sealing member 15, and the sealing member 15 is hermetically laser welded to the housing 10.

[0062] Next, in the initial charging and aging process S7, a charging device (not shown) is connected to the battery 1, and the battery 1 is initially charged. After that, the initially charged battery 1 is left standing for a predetermined time to age the battery 1. Thus, the battery 1 is completed.

[0063] In the method for manufacturing the battery 1 described above, in the housing roughening process S1, the pulsed laser LB is irradiated onto the inner surface 23 of the housing cover member 21 of the housing as described above, so that a valve periphery roughening portion 24 at the nanoscale with nanocolumns 26 standing is formed. Therefore, the valve periphery roughening portion 24 can be easily provided on the inner surface 23 of the housing. Then, in the resin molding process S3, while filling the resin material 45 between the nanocolumns 26 standing in the valve periphery roughening portion 24, the clogging suppression resin protrusion 40 is molded. Therefore, the clogging suppression resin protrusion 40 that is firmly joined to the valve periphery roughening portion 24 can be provided.

[0064] In the first embodiment, the terminal resin member 70 and the clogging suppression resin protrusion 40 are integrally molded, so that the terminal resin member 70 and the clogging suppression resin protrusion 40 can be easily and inexpensively provided.

[0065] (Second Embodiment)

[0066] Next, the second embodiment will be described (refer to Figure 10 and Figure 11 ). In addition, the description of the same parts as those in the first embodiment will be omitted or simplified. In the battery 1 of the first embodiment, the clogging suppression resin protrusion 40 is provided on both sides in the longitudinal direction (battery width direction BH) of the housing cover member 21 around the safety valve 30 on the inner surface 23 of the housing. In contrast, in the battery (an example of the power storage device of the present invention) 100 of the second embodiment, the clogging suppression resin protrusion 140 is provided on both sides in the short side direction (battery thickness direction CH) of the housing cover member 21 around the safety valve 30 on the inner surface 23 of the housing.

[0067] Specifically, the inner surface 23 of the housing cover member 21 has a pair of valve periphery roughening portions 124 that are roughened around the safety valve 30. These valve periphery roughening portions 124 are respectively provided on one side CH1 and the other side CH2 in the short side direction (battery thickness direction CH) of the housing cover member 21 around the safety valve 30 on the inner surface 23 of the housing in a form that extends substantially along the longitudinal direction (battery width direction BH) of the housing cover member 21. Each valve periphery roughening portion 124 is the same as the valve periphery roughening portion 24 of the first embodiment and becomes a nanoscale nano-roughening portion. That is, the valve periphery roughening portion 124 has a plurality of bowl-shaped recesses 25 (refer to Figure 7 ), and nanocolumns 26 stand in each bowl-shaped recess 25 (refer toFigure 5 and Figure 7 )

[0068] On a pair of valve peripheral roughened portions 124 on the inner side surface 23 of the housing, plugging suppression resin protrusions 140 protruding inwardly EH are respectively joined. That is, the pair of plugging suppression resin protrusions 140 extend substantially along the long side direction (battery width direction BH) of the housing cover member 21 on one side CH1 and the other side CH2 in the short side direction (battery thickness direction CH) of the housing cover member 21 around the safety valve 30, and protrude inwardly EH respectively. The plugging suppression resin protrusions 140 of the second embodiment can also suppress the fragments of the electrode body 50 from plugging the safety valve 30 from the inner side EH to the outer side DH when the electrode body 50 breaks. In addition, the plugging suppression resin protrusions 140 are joined to the valve peripheral roughened portions 124 with a strong bonding force by filling a resin material 45 between the nano-columns 26 standing on the valve peripheral roughened portions 124 on the inner side surface 23 of the housing.

[0069] The battery 100 of the second embodiment also has plugging suppression resin protrusions 140 provided around the safety valve 30 on the inner side surface 23 of the housing cover member 21. Therefore, since the fragments of the broken electrode body 50 can be prevented from plugging the safety valve 30, the safety valve 30 can function properly. Further, a resin material 45 is filled between the nano-columns 26 standing on the valve peripheral roughened portions 124, thereby joining the plugging suppression resin protrusions 140 to the valve peripheral roughened portions 124. Therefore, the bonding strength between the housing cover member 21 and the plugging suppression resin protrusions 140 can be improved.

[0070] The battery 100 of the second embodiment can also be manufactured in the same manner as the battery 1 of the first embodiment. Therefore, the manufacturing method of the battery 100 of the second embodiment can also obtain the same effects as the manufacturing method of the battery 1 of the first embodiment.

[0071] In addition, in the first embodiment, in the liquid injection and sealing process S6, if the electrolytic solution 5 is ejected from the front end of the liquid injection nozzle inserted into the liquid injection hole 21k to one side BH1 and the other side BH2 in the battery width direction BH, the electrolytic solution 5 may encounter the plugging suppression resin protrusion 40 extending in the battery thickness direction CH and generate bubbles, or the electrolytic solution 5 may adhere to the inner side surface 23 of the housing cover member 21. In contrast, in the second embodiment, since the plugging suppression resin protrusions 140 are provided at both ends in the battery thickness direction CH in a form extending along the battery width direction BH, the electrolytic solution 5 ejected from the front end of the liquid injection nozzle to the battery width direction BH is difficult to encounter the plugging suppression resin protrusions 140. Therefore, there are advantages that it is difficult to generate bubbles and the electrolytic solution 5 is difficult to adhere to the inner side surface of the housing.

[0072] (Embodiment 3)

[0073] Next, a description will be given of the third embodiment (see Figure 12 and Figure 13 ). In addition, the description of the parts that are the same as those in Embodiment 1 or 2 will be omitted or simplified. In the battery 200 (an example of the power storage device of the present invention) of the present Embodiment 3, the form of the clogging suppression resin convex portion 240 is different from the forms of the clogging suppression resin convex portions 40 and 140 of Embodiment 1 and 2, and a plurality of dot-like clogging suppression resin convex portions 240 are provided around the safety valve 30 on the inner side surface 23 of the housing over the entire circumference.

[0074] Specifically, the inner side surface 23 of the housing cover member 21 has a plurality of dot-like valve-peripheral roughened portions 224 arranged with a gap over the entire circumference around the safety valve 30. Each valve-peripheral roughened portion 224 is the same as the valve-peripheral roughened portions 24 and 124 of Embodiment 1 and 2 and is a nano-scale nano-roughened portion. That is, the valve-peripheral roughened portion 224 has a plurality of bowl-shaped recesses 25 (see Figure 7 ), and nano-columns 26 stand in each bowl-shaped recess 25 (see Figure 5 and Figure 7 ).

[0075] To each of the plurality of valve-peripheral roughened portions 224 on the inner side surface 23 of the housing, a clogging suppression resin convex portion 240 protruding inwardly EH in a dot shape is joined. That is, the plurality of clogging suppression resin convex portions 240 are arranged with a gap over the entire circumference around the safety valve 30 and protrude inwardly EH respectively. The clogging suppression resin convex portion 240 of the present Embodiment 3 can also suppress the fragments of the electrode body 50 from blocking the safety valve 30 from the inner side EH to the outer side DH when the electrode body 50 breaks. In addition, the clogging suppression resin convex portion 240 is joined to the valve-peripheral roughened portion 224 with a strong bonding force by filling a resin material 45 between the nano-columns 26 standing in the valve-peripheral roughened portion 224 on the inner side surface 23 of the housing.

[0076] The battery 200 of the present Embodiment 3 also has a clogging suppression resin convex portion 240 provided around the safety valve 30 on the inner side surface 23 of the housing cover member 21. Therefore, since it is possible to suppress the fragments of the broken electrode body 50 from blocking the safety valve 30, the safety valve 30 can function properly. Further, a resin material 45 is filled between the nano-columns 26 standing in the valve-peripheral roughened portion 224, thereby joining the clogging suppression resin convex portion 240 and the valve-peripheral roughened portion 224. Therefore, the bonding strength between the housing cover member 21 and the clogging suppression resin convex portion 240 can be improved.

[0077] In addition, the battery 200 of the third embodiment can also be manufactured in the same manner as the batteries 1 and 100 of the first and second embodiments. Therefore, the manufacturing method of the battery 200 of the third embodiment can also achieve the same effects as the manufacturing methods of the batteries 1 and 100 of the first and second embodiments.

[0078] As described above, the present invention has been described with reference to the first to third embodiments. However, the present invention is not limited to the first to third embodiments, and can be appropriately modified and applied without departing from the gist thereof.

Claims

1. An electric storage device comprising: a housing having a housing part made of metal; a safety valve, the safety valve being disposed on the housing component; and an electrode body, the electrode body being accommodated in the housing, The power storage device is characterized in that The housing member has a roughened valve periphery portion around the safety valve on the inner side surface of the housing located inside. The electrical storage device further includes a clogging prevention resin protrusion, which is a resin protrusion that is bonded to the valve surrounding roughened portion on the inner side of the housing and protrudes to the inner side, and when the electrode body is broken, the clogging prevention resin protrusion prevents the fragments of the electrode body from clogging the safety valve from the inner side. Nanocolumns are arranged in a roughened portion around the valve. The nanocolumns are formed by particles of a metal forming the housing member being connected in a beaded manner to form a columnar shape and have a height of 50 nm or more. The clogging prevention resin projection is bonded to the valve periphery roughened portion by filling a resin material forming the clogging prevention resin projection between the forested nanocolumns.

2. A method for manufacturing an electric storage device, the electric storage device comprising: a housing having a housing part made of metal; a safety valve, the safety valve being disposed on the housing component; and an electrode body, the electrode body being accommodated in the housing, The housing member has a roughened valve periphery portion around the safety valve on the inner side surface of the housing located inside. The electrical storage device further includes a clogging prevention resin protrusion, which is a resin protrusion that is bonded to the valve surrounding roughened portion on the inner side of the housing and protrudes to the inner side, and when the electrode body is broken, the clogging prevention resin protrusion prevents the fragments of the electrode body from clogging the safety valve from the inner side. Nanocolumns are arranged in a roughened portion around the valve. The nanocolumns are formed by particles of a metal forming the housing member being connected in a beaded manner to form a columnar shape and have a height of 50 nm or more. The clogging prevention resin projection is bonded to the valve periphery roughened portion by filling the space between the forested nanocolumns with a resin material forming the clogging prevention resin projection. The method for manufacturing an electric storage device is characterized by comprising: a shell roughening step of intermittently irradiating the inner side surface of the shell member with a pulsed laser in a staggered irradiation position, thereby forming a roughened portion around the valve where the nano-pillars are numerous; and The resin molding step is to fill the resin material between the nano-pillars arranged in the roughened portion around the valve, and to mold the clogging-inhibiting resin protrusions.

3. The method for manufacturing an electric storage device according to claim 2, wherein: The housing member has an insertion hole, The power storage device further comprises: a terminal member inserted into the insertion hole of the housing member; and a terminal resin component which insulates the housing component from the terminal component and is bonded to the housing component and the terminal component to fix the terminal component to the housing component, In the resin molding step, the terminal resin component joined to the housing component and the terminal component is molded while the terminal component is inserted into the insertion hole of the housing component, and the clogging suppression resin protrusion joined to the housing component is molded.

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