Power storage device and method for manufacturing power storage device

Abstract

The invention provides a power storage device and a method for manufacturing the power storage device. The electricity storage device includes a housing member, a terminal member, and a resin member that insulates between the housing member and the terminal member and is joined to the housing member and the terminal member in an airtight manner. The resin member includes a thermoplastic main resin and a fibrous filler. The resin member has a resin inner portion and a resin outer portion, an uneven portion is provided on at least one of a resin inner surface facing the inner side and a resin joining surface facing the outer side in the resin inner portion, and the orientation of fibers of the filler contained in the resin inner portion is disturbed by molding the uneven portion.

Description

Technical Field

[0001] The present disclosure relates to a power storage device in which a terminal component is fixed via a resin component including a fibrous filler composed of a plurality of fibers to a housing component 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 positive and negative terminal components are respectively fixed via a resin component to a rectangular plate-shaped housing cover component (housing component) constituting a rectangular parallelepiped box-shaped housing. Specifically, the positive and negative terminal components are respectively inserted through insertion holes provided in the housing cover component and extend from the inside of the housing to the outside. The resin component insulates between the housing cover component and the terminal components and is hermetically joined to the positive and negative terminal components, so that the terminal components are fixed to the housing cover component.

[0003] When manufacturing such a battery, there is a case where insert molding is performed on the resin component. That is, in a state where the terminal component is inserted through the insertion hole of the housing cover component, insert molding is performed on the resin component, so that the terminal component is fixed to the housing cover component via the resin component. In addition, as related prior art, for example, Patent Document 1 can be cited.

[0004] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2022-079172

[0005] However, in the above battery, in order to improve the strength of the resin component or to make the linear expansion coefficient of the resin material forming the resin component close to the linear expansion coefficient of the metal forming the housing component and the terminal component, there is a case where a fibrous filler composed of glass fiber, carbon fiber, etc. is added to the resin material.

[0006] However, at the time of insert molding, since the fibrous filler contained in the molten resin tends to be oriented along the flow of the molten resin (since the fibers of the filler tend to be oriented in such a way that the long side direction of the fibers forming the filler becomes parallel to the flow of the molten resin), the filler also tends to be oriented in the formed resin component. If the filler is oriented in the resin component, anisotropy occurs in the properties (linear expansion coefficient, strength, etc.) of the resin component in the direction along the orientation direction of the fibrous filler and in the direction orthogonal to the orientation direction of the filler, which is not preferable. For example, when a thermal cycle test is performed on the battery, depending on the relationship between the direction of the stress generated between the resin component and the housing component or the terminal component and the orientation direction, there is a case where cracks (sealing failure) are generated between the resin component and the housing component or the terminal component. Summary of the Invention

[0007] The present disclosure has been made in view of the above situation, and provides a power storage device and a method for manufacturing a power storage device with less anisotropy in the properties (such as coefficient of linear expansion, strength, etc.) of a resin member that fixes a terminal member to a housing member. (1)

[0009] A power storage device according to one aspect of the present disclosure for solving the above problems includes: a housing member including an insertion through-hole; a terminal member inserted into the insertion through-hole of the housing member; and a resin member that insulates between the housing member and the terminal member and is hermetically joined to the housing member and the terminal member to fix the terminal member to the housing member. The resin member is formed of a resin material and is formed by insert molding. The resin material includes a thermoplastic main resin and a fibrous filler composed of a plurality of fibers. The resin member has: a resin inner portion located inside the housing member; and a resin outer portion that passes through the insertion through-hole from the resin inner portion and extends to the outside of the housing member. At least one of the resin inner surface facing the inside and the resin joint surface facing the outside and joined to the housing member in the resin inner portion is provided with uneven portions. By forming the uneven portions, the orientation of the fibers of the filler contained in the resin inner portion is disordered.

[0010] In the above power storage device, uneven portions are provided on at least one of the resin inner surface and the resin joint surface in the resin inner portion of the resin member. By forming the uneven portions, the orientation of the fibers of the filler contained in the resin inner portion is disordered. Therefore, compared with the case where the uneven portions are not provided, the orientation of the fibers of the filler is disordered in the resin inner portion. Specifically, the degree of orientation of the filler in each part of the resin inner portion (the ratio of a certain proportion of the fibers in the plurality of fibers of the filler contained in each part facing a specific direction) becomes lower (the amount of fibers facing a specific direction decreases in each part of the resin inner portion). In addition, in adjacent parts of the resin inner portion, the filler does not form the same orientation direction, but forms a form in which the orientation direction of the filler changes when the position of the part is slightly changed. Therefore, in this power storage device, compared with the case where the above uneven portions are not provided, the anisotropy in the properties (such as coefficient of linear expansion, strength, etc.) of the resin member is less.

[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 so-called "main resin" refers to the resin material with the largest weight proportion in the resin materials constituting the resin material. Examples of thermoplastic resins that can be used as the main resin include polyphenylene sulfide (PPS), polyether ether ketone (PEEK), polytetrafluoroethylene (PTFE), perfluoroalkoxy alkane (PFA), etc.

[0013] Examples of the fibers forming the "fibrous filler" include glass fibers, carbon fibers, etc.

[0014] In addition, in the resin material, materials other than the above-mentioned thermoplastic main resin and fibrous filler, such as thermoplastic elastomers, may also be included. (2)

[0016] In the energy storage device described in (1), the energy storage device may be configured such that a plurality of convex portions and concave portions forming the above-mentioned concave and convex portions are arranged in a staggered lattice pattern.

[0017] By arranging a plurality of convex portions and concave portions forming the concave and convex portions in a staggered lattice pattern, with the formation of the concave and convex portions, the orientation of the fibers of the filler contained in the inner part of the resin is further disordered. Therefore, in this energy storage device, especially in terms of the characteristics of the resin component, the anisotropy is small. (3)

[0019] In addition, another method is a method for manufacturing a power storage device, wherein the power storage device includes: a housing member including an insertion through-hole; a terminal member inserted into the insertion through-hole of the housing member; and a resin member that insulates between the housing member and the terminal member and is hermetically joined to the housing member and the terminal member to fix the terminal member to the housing member. The resin member is made of a resin material and is formed by insert molding. The resin material includes a thermoplastic main resin and a fibrous filler composed of a plurality of fibers. The resin member has: a resin inner portion located inside the housing member; and a resin outer portion that passes through the insertion through-hole from the resin inner portion and extends to the outside of the housing member. At least one of the resin inner surface facing the inside and the resin joint surface facing the outside and joined to the housing member in the resin inner portion is provided with uneven portions. By forming the uneven portions, the orientation of the fibers of the filler contained in the resin inner portion is disordered. The method for manufacturing the power storage device includes an insert molding process. In a state where the terminal member is inserted into the insertion through-hole of the housing member, the resin member is insert molded using the resin material. The insert molding process includes the following processes: a chamber forming process of forming a chamber for molding the resin member by a molding die, the housing member, and the terminal member; and an injection molding process of injecting a molten resin of the resin material into the chamber to fill the chamber with the molten resin to mold the resin member. The chamber has an outer portion forming chamber for forming the resin outer portion and an inner portion forming chamber for forming the resin inner portion. The inner portion forming surface forming the inner portion forming chamber has an uneven portion forming portion for forming the uneven portions. In the injection molding process, the flow of the molten resin is disordered by the uneven portion forming portion, so that the orientation of the fibers of the filler contained in the molten resin is disordered, and the resin inner portion having the uneven portions is molded.

[0020] In the method for manufacturing the power storage device described above, in the insert molding process, the flow of the molten resin is disordered by the uneven portion forming portion provided on the inner portion forming surface of the inner portion forming chamber, so that the orientation of the fibers of the filler contained in the molten resin is disordered. Therefore, compared with the case where the uneven portion forming portion is not provided on the inner portion forming surface, it is possible to mold a resin member in which the orientation of the fibers forming the filler is disordered. Thus, a power storage device with less anisotropy in the characteristics of the resin member can be manufactured.

[0021] In addition, in the case where the uneven portions are provided on the resin inner surface of the resin inner portion of the resin member, for example, as described later in Embodiment 1, the uneven forming portion is provided on the molding die used in the insert molding process. That is, the uneven forming portion is provided on the portion of the inner forming surface of the inner portion forming chamber that is constituted by the molding die. Alternatively, as described in Embodiment 3, the uneven forming portion is provided on the portion of the terminal member that is joined to the resin inner surface. That is, the uneven forming portion can also be provided on the portion of the inner forming surface of the inner portion forming chamber that is constituted by the terminal member.

[0022] On the other hand, in the case where the uneven portions are provided on the resin joint surface of the resin inner portion of the resin member, as described in Embodiment 2, the uneven forming portion is provided on the portion of the housing member that is joined to the resin inner portion. That is, the uneven forming portion is provided on the portion of the inner forming surface of the inner portion forming chamber that is constituted by the housing member. (4)

[0024] In the manufacturing method of the power storage device described in (3), it can be: the plurality of convex portions and concave portions forming the above-mentioned uneven portions are arranged in a staggered lattice pattern, and the plurality of convex portion forming portions and concave portion forming portions forming the above-mentioned uneven forming portion are arranged in a staggered lattice pattern.

[0025] In the manufacturing method of the above-mentioned power storage device, since the plurality of convex portion forming portions and concave portion forming portions forming the uneven forming portion are arranged in a staggered lattice pattern, the orientation of the fibers of the filler in the molten resin can be further disordered, and a resin member with the orientation of the fibers of the filler further disordered can be formed. Thereby, a power storage device with less anisotropy in the characteristics of the resin member can be manufactured. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a perspective view of the battery according to Embodiment 1.

[0027] Figure 2 It is a partial cross-sectional view of the battery according to Embodiment 1 along the battery height direction and the battery width direction.

[0028] Figure 3 Relating to Embodiment 1, it is a cross-sectional view along the battery height direction and the battery width direction near the resin member, and it is Figure 5 a cross-sectional view taken along the line A - A in

[0029] Figure 4 Relating to Embodiment 1, it is a cross-sectional view along the battery height direction and the battery thickness direction near the resin member, and it is Figure 5 a cross-sectional view taken along the line B - B in

[0030] Figure 5 Regarding Embodiment 1, it is a top view observed from the inside of the housing cover member near the resin member.

[0031] Figure 6 It is a flowchart of the manufacturing method of the battery according to Embodiment 1.

[0032] Figure 7 Regarding the manufacturing method of the battery according to Embodiment 1, it is an explanatory diagram showing the state of injecting molten resin into the cavity in the insert molding process.

[0033] Figure 8 Regarding the manufacturing method of the battery according to Embodiment 1, it is an explanatory diagram showing the state where the resin member is molded in the insert molding process.

[0034] Figure 9 Regarding Embodiment 2, it is a cross-sectional view along the battery height direction and the battery width direction near the resin member, corresponding to Figure 3 the corresponding one.

[0035] Figure 10 Regarding the manufacturing method of the battery according to Embodiment 2, it is an explanatory diagram showing the state of injecting molten resin into the cavity in the insert molding process, corresponding to Figure 7 the corresponding one.

[0036] Figure 11 Regarding Embodiment 3, it is a cross-sectional view along the battery height direction and the battery width direction near the resin member, corresponding to Figure 3 the corresponding one.

[0037] Figure 12 Regarding the manufacturing method of the battery according to Embodiment 3, it is an explanatory diagram showing the state of injecting molten resin into the cavity in the insert molding process, corresponding to Figure 7 the corresponding one.

[0038] Explanation of reference numerals:

[0039] 1, 100, 200... battery (power storage device); 10... housing; 25... housing cover member (housing component); 25h... insertion through-hole; 40... terminal component; 50, 150, 250... resin components; 51... resin outer part; 52, 152, 252... resin inner parts; 52a, 152a, 252a... resin joint surfaces; 52b, 152b, 252b... resin inner side surfaces; 52w, 152w, 252w... uneven parts; 52t, 152t, 252t... convex parts; 52v, 152v, 252v... concave parts; 55... resin material; 55M... molten resin; 56... main resin; 58... filler; DH... outside (of the housing cover member); EH... inside (of the housing cover member); DE... molding die; DBw... uneven molding part (provided in the molding die); DBt... convex part molding part (provided in the molding die); DBv... concave part molding part (provided in the molding die); 125w... uneven molding part (provided in the housing cover member); 125t... convex part molding part (provided in the housing cover member); 125v... concave part molding part (provided in the housing cover member); 244w... uneven molding part (provided in the flange part of the terminal component); 244t... convex part molding part (provided in the flange part of the terminal component); 244v... concave part molding part (provided in the flange part of the terminal component); FB, FC, FD... inner part forming chambers; FBn, FCn, FDn... inner part forming surfaces; S2... insert molding process; S21... chamber forming process; S22... injection molding process. Detailed Description of the Embodiment

[0040] (Embodiment 1)

[0041] Hereinafter, a first embodiment of the present disclosure will be described with reference to the accompanying drawings. Figure 1 A perspective view showing the battery (power storage device) 1 of the present Embodiment 1, Figure 2 A partial cross-sectional view showing the battery 1. In addition, Figure 3 and Figure 4 A magnified cross-sectional view showing the vicinity of the resin component 50, Figure 5 A magnified top view seen from the inside EH of the vicinity of the resin component 50. In addition, hereinafter, the battery height direction AH, the battery width direction BH, and the battery thickness direction CH of the battery 1 are determined as Figure 1 and Figure 2 the directions shown for description.

[0042] The battery 1 is a rectangular (cuboid-shaped) and sealed lithium-ion secondary battery mounted on vehicles such as hybrid vehicles, plug-in hybrid vehicles, and electric vehicles. The battery 1 is composed of a housing 10, an electrode body 30 housed in the housing 10, an electrolytic solution 5, and positive and negative terminal components 40 fixed to the housing 10 via resin components 50, etc. The electrode body 30 is covered in the housing 10 by a bag-shaped insulating holder 7 made of an insulating film.

[0043] Among them, the housing 10 is made of metal (aluminum in the present Embodiment 1), has a cuboid box shape, and is composed of a housing main body component 20 and a housing cover component 25. The housing main body component 20 has a bottomed square tube shape with a rectangular opening 20c and houses the electrode body 30 inside. The housing cover component 25 has a rectangular plate shape and closes the opening 20c of the housing main body component 20. In the present Embodiment 1, the housing cover component 25 corresponds to the above-mentioned "housing component". The opening 20c of the housing main body component 20 and the peripheral part 25f of the housing cover component 25 are welded in an airtight manner throughout the circumference. An air release valve 11 that breaks and opens when the internal pressure of the housing 10 exceeds the opening pressure is provided on the housing cover component 25. In addition, a liquid injection hole 25k is provided on the housing cover component 25, and the liquid injection hole 25k is sealed in an airtight manner by a circular plate-shaped sealing component 12 made of aluminum.

[0044] The electrode body 30 has a cuboid shape and is a stacked type, and is formed by alternately stacking a plurality of rectangular positive electrode plates 31 and a plurality of rectangular negative electrode plates 32 in the battery thickness direction CH via a rectangular separator 33 made of a resin porous film. On one side BH1 in the battery width direction BH of the electrode body 30, the current collector foils of the respective positive electrode plates 31 overlap in the battery thickness direction CH to form a positive current collector portion 30c. The positive current collector portion 30c is conductively connected to the positive terminal component 40. In addition, on the other side BH2 in the battery width direction BH of the electrode body 30, the current collector foils of the respective negative electrode plates 32 overlap in the battery thickness direction CH to form a negative current collector portion 30d. The negative current collector portion 30d is conductively connected to the negative terminal component 40.

[0045] Near the ends on one side BH1 and the other side BH2 in the battery width direction BH of the housing cover component 25, circular insertion holes 25h are respectively provided. In the insertion hole 25h on one side BH1, a positive terminal component 40 made of aluminum is inserted, and the terminal component 40 is fixed to the housing cover component 25 in a state of being insulated from the housing cover component 25 via a resin component 50. In the insertion hole 25h on the other side BH2, a negative terminal component 40 made of copper is inserted, and the terminal component 40 is fixed to the housing cover component 25 in a state of being insulated from the housing cover component 25 via a resin component 50.

[0046] Since the positive and negative terminal components 40 have the same form, the following description will focus on them. The terminal component 40 is a component formed by welding together a terminal outer part (terminal outer component) 41 and a terminal inner part (terminal inner component) 42. The terminal outer part 41 is in the shape of a rectangular plate extending in the battery width direction BH and the battery thickness direction CH, and is located outside DH (the upper side AH1 in the first embodiment) of the housing cover component 25.

[0047] On the other hand, the terminal inner part 42 is mainly located inside EH (the lower side AH2 in the first embodiment) of the housing cover component 25 and is connected to the terminal outer part 41 through the insertion hole 25h. The terminal inner part 42 is composed of a plate-shaped flange part 44, a bottomed cylindrical protruding part 43 protruding upward from the central part of the flange part 44, and an extending part 45 extending downward from the flange part 44. The flange part 44 has a rectangular outer periphery and a circular hole in the center, and is arranged parallel to the housing cover component 25. The protruding part 43 passes through the insertion hole 25h and protrudes outside DH, and is welded to the terminal outer part 41 through its bottom. The extending part 45 bends at the end of the flange part 44 on the side CH1 in the battery thickness direction CH and extends downward to the lower side AH2. The positive terminal component 40 is welded to the positive current collector 30c of the electrode body 30 at the front end of its extending part 45, so as to be conductively connected to the positive current collector 30c. In addition, the negative terminal component 40 is welded to the negative current collector 30d of the electrode body 30 at the front end of its extending part 45, so as to be conductively connected to the negative current collector 30d.

[0048] Next, the resin component 50 will be described. The positive resin component 50 insulates between the housing cover component 25 and the positive terminal component 40, and is hermetically joined to the housing cover component 25 and the terminal component 40, so that the terminal component 40 is fixed to the housing cover component 25. In addition, the negative resin component 50 insulates between the housing cover component 25 and the negative terminal component 40, and is hermetically joined to the housing cover component 25 and the terminal component 40, so that the terminal component 40 is fixed to the housing cover component 25. Since the resin components 50 on the positive and negative sides have the same form, the following description will focus on them.

[0049] The resin component 50 is made of a resin material 55, which includes a thermoplastic main resin 56, a thermoplastic elastomer 57, and a fibrous filler 58. In the present Embodiment 1, the thermoplastic main resin 56 is polyphenylene sulfide (PPS), the thermoplastic elastomer 57 is a thermoplastic polyurethane elastomer, and the fibrous filler 58 is a filler composed of a plurality of glass fibers with a diameter of approximately 10 μm and a length of 300 μm. The weight ratio of the main resin 56, the elastomer 57, and the filler 58 is main resin:elastomer:filler = 40:10:50.

[0050] The resin component 50 is composed of a resin inner part 52 located inside the housing cover component 25 at EH, and a resin outer part 51 that passes through the insertion hole 25h from the resin inner part 52 and extends to the outside of the housing cover component 25 at DH. Among them, the resin outer part 51 surrounds the periphery of the terminal outer part 41 while insulating the terminal outer part 41 from the housing cover component 25, and surrounds the upper outer peripheral surface 43d of the upper side AH1 of the protruding part 43 in the terminal inner part 42 to insulate the upper outer peripheral surface 43d of the protruding part 43 from the housing cover component 25.

[0051] On the other hand, the resin inner part 52 is in a substantially rectangular plate shape with a dimension in the battery width direction BH longer than the dimension in the battery thickness direction CH. It surrounds the lower outer peripheral surface 43e of the lower side AH2 of the protruding part 43 in the terminal inner part 42 to insulate the lower outer peripheral surface 43e of the protruding part 43 from the housing cover component 25, and surrounds the periphery of the flange part 44 of the terminal inner part 42 while insulating the flange part 44 from the housing cover component 25.

[0052] The resin inner part 52 has a resin inner surface 52b facing the inside EH and a resin bonding surface 52a facing the outside DH and bonding to the housing cover component 25. In addition, for the resin inner surface 52b, in addition to the part exposed inside the housing 10, it also includes a part that engages with the outer surface 44a of the flange part 44 of the terminal component 40. In the present Embodiment 1, in the above resin bonding surface 52a and resin inner surface 52b, uneven portions 52w are provided on the resin inner surface 52b. The uneven portions 52w are formed in more than 20% of the entire area of the resin inner surface 52b (substantially 50% of the area in the present Embodiment 1). The plurality of convex portions 52t and concave portions 52v forming the uneven portions 52w are arranged in a staggered lattice pattern (refer to Figure 5 ). As described later, with the formation of the uneven portions 52w, the orientation of the plurality of glass fibers of the filler 58 contained in the resin inner part 52 forming the resin component 50 is disordered.

[0053] In such a battery 1, uneven portions 52w are provided on the resin inner surface 52b of the resin inner portion 52 of the resin member 50. Due to the formation of the uneven portions 52w, the orientation of the glass fibers forming the filler 58 contained in the resin inner portion 52 is disordered. Therefore, compared with the case where the uneven portions 52w are not provided, the orientation of the glass fibers forming the filler 58 in the resin inner portion 52 is disordered. Specifically, in each part of the resin inner portion 52, the amount of glass fibers of the filler 58 oriented in a specific direction (the battery width direction BH in the first embodiment) becomes smaller. In addition, between adjacent parts of the resin member 50, the filler 58 does not form the same orientation direction, but is configured such that, for example, in the part near the convex portion 52t and the part near the adjacent concave portion 52v in the resin member 50, the orientation direction of the filler 58 changes. Therefore, for this battery 1, compared with the case where there are no uneven portions 52w, the anisotropy in the characteristics (linear expansion coefficient, strength, etc.) of the resin member 50 is less.

[0054] Moreover, in the first embodiment, the plurality of convex portions 52t and concave portions 52v forming the uneven portions 52w are arranged in a staggered lattice pattern. Therefore, with the formation of the uneven portions 52w, the orientation of the glass fibers of the filler 58 contained in the resin inner portion 52 is further disordered. Therefore, in this battery 1, the anisotropy in the characteristics of the resin member 50 is particularly small.

[0055] Next, a method for manufacturing the above battery 1 will be described (refer to Figures 6 - 8 ). First, a case lid member 25, and positive and negative terminal outer portions 41 and terminal inner portions 42 are prepared in advance. Then, in the "terminal forming step S1" (refer to Figure 6 ), positive and negative terminal members 40 are formed. Specifically, in a pair of insertion holes 25h of the case lid member 25, the protruding portions 43 of the positive and negative terminal inner portions 42 are inserted through from the inner side EH to the outer side DH of the case lid member 25. After that, the positive and negative terminal outer portions 41 are brought into contact with the bottom of the protruding portions 43 from the outer side DH of the case lid member 25, and the protruding portions 43 and the terminal outer portions 41 are laser welded to form the positive and negative terminal members 40. The above terminal members 40 are in a state of being inserted through the insertion holes 25h of the case lid member 25.

[0056] Next, in the "insert molding step S2" (refer to Figure 6 ), with the positive and negative terminal members 40 inserted through a pair of insertion holes 25h of the case lid member 25, a pair of resin members 50 are insert molded using the above resin material 55. This insert molding step S2 is performed using a molding die DE having an upper die DA and a lower die DB (refer to Figure 7)。The upper mold DA has: a pair of (positive electrode side and negative electrode side) outer surface forming parts DA1 that form the exposed surface 51m of the resin outer part 51 in the resin part 50; and an outer lid adhering part DA2 that surrounds the outer surface forming part DA1 and extends radially outward, and adheres closely to the outer surface 25a of the housing lid part 25 in opposition. On the other hand, the lower mold DB has: a pair of (positive electrode side and negative electrode side) inner surface forming parts DB1 that form the exposed surface 52m of the resin inner part 52 in the resin part 50; and an inner lid adhering part DB2 that surrounds the inner surface forming part DB1 and extends radially outward, and adheres closely to the inner surface 25b of the housing lid part 25 in opposition.

[0057] In the insert molding process S2, a pair of cavities FE for molding a pair of resin parts 50 are formed by the molding die DE, the housing lid part 25, and a pair of terminal parts 40. The cavity FE is composed of an outer part forming cavity FA for molding the resin outer part 51 in the resin part 50 and an inner part forming cavity FB for molding the resin inner part 52 in the resin part 50.

[0058] Among them, the outer part forming cavity FA is formed by the upper mold DA, the housing lid part 25, and the upper part of the protruding part 43 of the terminal outer part 41 and the terminal inner part 42 of the terminal part 40. Specifically, the outer part forming surface Fan forming the outer part forming cavity FA is composed of the outer forming surface Dan of the outer surface forming part DA1 of the upper mold DA, the outer surface 25a of the housing lid part 25 and the inner peripheral surface 25c of the insertion hole 25h, the inner surface 41b and the outer peripheral surface 41d of the terminal outer part 41, and the upper outer peripheral surface 43d of the protruding part 43 of the terminal inner part 42.

[0059] On the other hand, the inner portion forming chamber FB is formed by the lower mold DB, the housing cover member 25, and the flange portion 44 and the lower portion of the protruding portion 43 in the inner portion 42 of the terminal member 40. Specifically, the inner portion forming surface FBn of the inner portion forming chamber FB is composed of the inner forming surface DBn of the inner surface forming portion DB1 of the lower mold DB, the inner surface 25b of the housing cover member 25, the outer surface 44a and the outer peripheral surface 44d of the flange portion 44 of the inner portion 42 of the terminal, and the lower outer peripheral surface 43e of the protruding portion 43 of the inner portion 42 of the terminal. Among them, the inner forming surface DBn of the inner surface forming portion DB1 has an uneven forming portion DBw for forming the uneven portion 52w of the resin inner portion 52 of the resin member 50. The uneven forming portion DBw has a plurality of convex portion forming portions DBt for forming a plurality of convex portions 52t and a plurality of concave portion forming portions DBv for forming a plurality of concave portions 52v, and these convex portion forming portions DBt and concave portion forming portions DBv are arranged in an alternating lattice pattern.

[0060] In addition, a pair of injection nozzles NZ are arranged in the lower mold DB, and are configured to be able to inject the molten resin 55M of the resin material 55 into the inner portion forming chamber FB from the gates GT formed at the front ends of the respective injection nozzles NZ. Since the inner portion forming chamber FB and the outer portion forming chamber FA are connected in the insertion hole 25h, the molten resin 55M injected into the inner portion forming chamber FB is not only filled in the inner portion forming chamber FB, but also filled in the outer portion forming chamber FA through the insertion hole 25h as shown by the arrow P in Figure 7 for the flow of the molten resin 55M.

[0061] In the insert molding process S2, a chamber forming process S21 is performed, and then, an injection molding process S22 is performed (refer to Figure 6 ).

[0062] First, in the chamber forming process S21, a pair of chambers FE for forming a pair of resin members 50 are formed by the molding die DE, the housing cover member 25, and a pair of terminal members 40 (refer to Figure 7) Specifically, the above-mentioned housing cover member 25 and positive and negative terminal members 40 are arranged at specified positions on the lower mold DB. After that, the upper mold DA is moved downward toward the lower mold DB and overlapped on the lower mold DB to close the molding die DE. At this time, a part of the outer surface forming portion DA1 in the upper mold DA is closely attached to the outer side portion 41 of the terminal member 40 in an opposing manner, and the outer cover attachment portion DA2 is closely attached to the outer surface 25a of the housing cover member 25 in an opposing manner. Thus, the outer side forming cavity FA in the cavity FE is formed. In addition, a part of the inner surface forming portion DB1 in the lower mold DB is closely attached to the flange portion 44 of the inner side portion 42 of the terminal member 40 in an opposing manner, and the inner cover attachment portion DB2 is closely attached to the inner surface 25b of the housing cover member 25 in an opposing manner. Thus, the inner side forming cavity FB in the cavity FE is formed.

[0063] Next, in the injection molding process S22, the molten resin 55M obtained by melting the resin material 55 is injected into each cavity FE, and thus the cavity FE is filled with the molten resin 55M to form the resin members 50 respectively. Specifically, the molten resin 55M is injected into the two inner side forming cavities FB from each gate GT, covering the entire inner side forming cavity FB and the entire outer side forming cavity FA connected to the inner side forming cavity FB. At this time, since the uneven forming portion DBw is provided on the inner forming surface DBn of the inner surface forming portion DB1 of the lower mold DB, the flow of the molten resin 55M is disturbed compared to the case where the uneven forming portion DBw is not provided, and the orientation of the glass fibers of the filler 58 in the molten resin 55M is disturbed.

[0064] That is, in the case where the uneven forming portion DBw is not provided, the molten resin 55M mainly flows in the longitudinal direction of the resin inner side portion 52 (in Figure 7 and Figure 8 it is the left-right direction, and in the state where the battery 1 is formed, it is the battery width direction BH), so the filler 58 in the molten resin 55M also aligns along the flow orientation of the molten resin 55M (the glass fibers are oriented such that the longitudinal direction of the glass fibers of the filler 58 is parallel to the flow of the molten resin 55M). In contrast, in the first embodiment, due to the uneven forming portion DBw, the flow of the molten resin 55M is disturbed, and therefore, the orientation of the glass fibers of the filler 58 in the molten resin 55M is also disturbed.

[0065] Thereafter, the molten resin 55M is cooled, and the resin member 50 hermetically joined to the housing lid member 25 and the terminal member 40 is formed. That is, the entire molten resin 55M filled in the chamber FE is cooled, the resin inner portion 52 is formed in the inner portion forming chamber FB, and the resin outer portion 51 is formed in the outer portion forming chamber FA, thereby forming the two resin members 50 each composed of the resin inner portion 52 and the resin outer portion 51 (refer to Figure 8 ). Thereby, compared with the case where there is no uneven forming portion DBw, the resin member 50 in which the orientation of the glass fibers of the filler 58 is disordered is formed. Thereafter, the upper mold DA is moved upward, and the lid assembly 15 in which the positive and negative terminal members 40 are fixed to the housing lid member 25 via the resin member 50 is taken out from the lower mold DB.

[0066] Next, in the "electrode body connection process S3" (refer to Figure 6 ), an electrode body 30 obtained by laminating a positive electrode plate 31, a negative electrode plate 32, and a separator 33 is prepared, and the protruding portion 45 of the positive terminal member 40 in the lid assembly 15 is ultrasonically welded to the positive current collector portion 30c of the electrode body 30. In addition, the protruding portion 45 of the negative terminal member 40 in the lid assembly 15 is ultrasonically welded to the negative current collector portion 30d of the electrode body 30. Thereafter, the electrode body 30 is wrapped with a bag-shaped insulating holding member 7.

[0067] Next, in the "electrode body housing and housing forming process S4", a housing main body member 20 is prepared, the electrode body 30 covered with the insulating holding member 7 is inserted into the housing main body member 20, and the opening 20c of the housing main body member 20 is blocked by the housing lid member 25. Then, the opening 20c of the housing main body member 20 and the peripheral portion 25f of the housing lid member 25 are laser welded in an airtight manner over the entire circumference to form a housing 10 that houses the electrode body 30 therein.

[0068] Next, in the "electrolyte injection and sealing process S5", the electrolyte 5 is injected into the housing 10 through the electrolyte injection hole 25k, and the electrolyte 5 is allowed to soak into the electrode body 30. Thereafter, the injection hole 25k is covered from the outside by the sealing member 12, and the sealing member 12 is laser welded to the housing 10 in an airtight manner.

[0069] Next, in the "initial charging and aging process S6", a charging device (not shown) is connected to the battery 1, and the battery 1 is initially charged. Thereafter, the initially charged battery 1 is allowed to stand for a specified time to age the battery 1. Thus, the battery 1 is completed.

[0070] In the method for manufacturing the battery 1 described above, in the insert molding process S2, the uneven forming portion DBw provided on the inner forming surface FBn of the inner forming chamber FB of the insert molding die is used to disrupt the flow of the molten resin 55M, thereby disrupting the orientation of the glass fibers of the filler 58 contained in the molten resin 55M. Therefore, compared with the case where the uneven forming portion DBw is not provided on the inner forming surface FBn, it is possible to mold the resin member 50 in which the orientation of the glass fibers forming the filler 58 is disrupted. Thus, it is possible to manufacture the battery 1 with less anisotropy in the characteristics of the resin member 50.

[0071] Moreover, in the first embodiment, since the plurality of convex portion forming portions DBt and concave portion forming portions DBv forming the uneven forming portion DBw are arranged in a staggered lattice pattern, it is possible to further disrupt the orientation of the glass fibers of the filler 58 in the molten resin 55M, and it is possible to mold the resin member 50 in which the orientation of the glass fibers of the filler 58 is more disrupted. Thus, it is possible to manufacture the battery 1 with particularly little anisotropy in the characteristics of the resin member 50.

[0072] (Second Embodiment)

[0073] Next, the second embodiment will be described (see Figure 9 and Figure 10 ). In addition, the description of the parts that are the same as those in the first embodiment will be omitted or simplified.

[0074] In the battery 1 of the first embodiment, an uneven portion 52w is provided on the resin inner surface 52b of the resin inner portion 52 and the resin inner surface 52b among the resin joint surfaces 52a. In contrast, in the battery 100 of the second embodiment, the difference is that an uneven portion 152w is provided on the resin joint surface 152a among the resin inner surface 152b and the resin joint surfaces 152a of the resin inner portion 152.

[0075] In addition, in the method for manufacturing the battery 1 according to the first embodiment, an uneven forming portion DBw is provided on the lower die DB of the molding die DE, and the resin inner portion 52 having the uneven portion 52w is molded. In contrast, in the method for manufacturing the battery 100 according to the second embodiment, the difference is that an uneven forming portion 125w is provided on the inner surface 25b of the housing lid member 25, and the resin inner portion 152 having the uneven portion 152w is molded.

[0076] Specifically, the shape of the resin outer portion 51 in the resin component 150 according to the second embodiment is the same as that of the resin outer portion 51 in the first embodiment, but the shape of the resin inner portion 152 is different from that of the resin inner portion 52 in the first embodiment. That is, the resin inner portion 152 is substantially in the shape of a rectangular plate, and has a resin inner surface 152b facing the inner side EH and a resin joint surface 152a facing the outer side DH and joined to the housing cover member 25. In the second embodiment, on the resin joint surface 152a among these resin joint surfaces 152a and resin inner surfaces 152b, there is provided an uneven portion 152w formed by arranging a plurality of convex portions 152t and concave portions 152v in a staggered lattice pattern. Moreover, with the formation of the uneven portion 152w, the orientation of the glass fibers of the filler 58 contained in the resin inner portion 152 of the resin component 150 is disordered.

[0077] In addition, accordingly, on the inner surface 25b of the housing cover member 25, there is provided an uneven forming portion 125w having a shape corresponding to the uneven portion 152w of the resin joint surface 152a of the resin inner portion 152. That is, the uneven forming portion 125w has a plurality of convex portion forming portions 125t for forming a plurality of convex portions 152t and a plurality of concave portion forming portions 125v for forming a plurality of concave portions 152v, and these convex portion forming portions 125t and concave portion forming portions 125v are arranged in a staggered lattice pattern.

[0078] In the battery 100 according to the second embodiment, on the resin joint surface 152a of the resin inner portion 152 of the resin component 150, there is provided an uneven portion 152w. By the formation of the uneven portion 152w, the orientation of the glass fibers of the filler 58 contained in the resin inner portion 152 is disordered. Therefore, in the formed resin inner portion 152, the orientation of the glass fibers of the filler 58 is disordered, and the anisotropy in the characteristics (linear expansion coefficient, strength, etc.) of the resin component 150 is small. In particular, since the convex portions 152t and concave portions 152v forming the uneven portion 152w are arranged in a staggered lattice pattern, the anisotropy in the characteristics of the resin component 150 is particularly small. In addition, the same parts as those in the first embodiment have the same functions and effects as those in the first embodiment.

[0079] Next, a method for manufacturing the battery 100 will be described. In the second embodiment, the terminal forming step S1 is performed using the housing cover member 25 having the uneven forming portion 125w on the inner surface 25b to form the terminal member 40.

[0080] After that, in the insert molding step S2, a pair of resin components 150 are insert molded using the resin material 55 (refer to Figure 10)。The upper mold DA in the molding die DE is the same as the upper mold DA in Embodiment 1, but the lower mold DC is different from the lower mold DB in Embodiment 1. That is, in the lower mold DC of the present Embodiment 2, there is no concavo-convex forming portion on the inner forming surface DCn of the inner surface forming portion DC1, and the inner forming surface DCn becomes flat.

[0081] In the present Embodiment 2, a pair of inner portion forming chambers FC for forming the resin inner portion 52 of the resin member 50 is constituted by the lower mold DC, the housing cover member 25 having the concavo-convex forming portion 125w, and the terminal member 40. That is, the inner forming surface FCn of the inner portion forming chamber FC is formed by the inner forming surface DCn of the inner surface forming portion DC1 of the lower mold DC, the inner surface 25b of the housing cover member 25 having the concavo-convex forming portion 125w, the outer surface 44a and the outer peripheral surface 44d of the flange portion 44 of the terminal inner portion 42, and the lower outer peripheral surface 43e of the protruding portion 43 of the terminal inner portion 42.

[0082] In the insert molding process S2, if the molten resin 55M is injected into the inner portion forming chamber FC from the gate GT, the flow of the molten resin 55M is disturbed by the concavo-convex forming portion 125w provided on the inner surface 25b of the housing cover member 25, so that the orientation of the glass fibers of the filler 58 in the molten resin 55M is disturbed. Therefore, the resin member 150 is formed in a state where the orientation of the glass fibers of the filler 58 is disturbed.

[0083] In the manufacturing method of the battery 100 of the present Embodiment 2, in the insert molding process S2, the flow of the molten resin 55M is disturbed by the concavo-convex forming portion 125w provided on the inner surface 25b of the housing cover member 25, so that the orientation of the glass fibers forming the filler 58 is disturbed. Therefore, it is possible to form the resin member 150 in which the orientation of the glass fibers forming the filler 58 is disturbed, and a battery 100 with less anisotropy in the characteristics of the resin member 150 can be manufactured. Since in particular, the plurality of convex portion forming portions 125t and the concave portion forming portion 125v forming the concavo-convex forming portion 125w are arranged in a staggered lattice shape, the orientation of the glass fibers of the filler 58 in the molten resin 55M can be further disturbed, and the resin member 50 in which the orientation of the glass fibers of the filler 58 is more disturbed can be formed. In addition, the same parts as those in Embodiment 1 in Embodiment 2 have the same effects as those in Embodiment 1.

[0084] (Embodiment 3)

[0085] Next, a description will be given of the third embodiment (refer to Figure 11 and Figure 12)。In addition, descriptions of parts identical to those in Embodiment 1 or 2 are omitted or simplified. In the battery 200 of this Embodiment 3, similar to Embodiment 1, uneven portions 252w are provided on the resin inner surface 252b of the resin inner portion 252 of the resin inner side portion 252. However, the difference between this Embodiment 3 and Embodiment 1 is that, instead of providing an uneven forming portion in the lower mold of the molding die DE as in Embodiment 1, an uneven forming portion 244w is provided on the flange portion 244 of the terminal inner portion 42 of the terminal member 40, thereby forming the resin inner portion 252 having the uneven portions 252w.

[0086] Specifically, in the terminal member 40 according to this Embodiment 3, the shape of the flange portion 244 in the terminal inner portion 42 is different from that of the flange portion 44 in Embodiments 1 and 2. That is, the flange portion 244 of this Embodiment 3 has a shape that is longer in the battery width direction BH than the flange portion 44 of Embodiments 1 and 2, and the outer surface 244a of the flange portion 244 is joined to the resin inner surface 252b of the resin inner portion 252 of the resin member 250 over a relatively wide area. Moreover, an uneven forming portion 244w formed by arranging a plurality of convex portion forming portions 244t and concave portion forming portions 244v in a staggered lattice pattern is provided on the outer surface 244a of the flange portion 244.

[0087] In addition, the resin member 250 according to this Embodiment 3 is composed of a resin outer portion 51 identical to that in Embodiment 1 and a resin inner portion 252 that is slightly different in shape from that in Embodiment 1 and is joined to the outer surface 244a of the flange portion 244 of the terminal member 40 over a relatively wide area. The resin inner portion 252 is substantially in the shape of a rectangular plate and has a resin inner surface 252b facing the inner side EH and a resin joint surface 252a facing the outer side DH. On the resin inner surface 252b of this Embodiment 3, uneven portions 252w formed by arranging a plurality of convex portions 252t and concave portions 252v in a staggered lattice pattern are provided corresponding to the uneven forming portion 244w of the outer surface 244a of the flange portion 244.

[0088] In the battery 200 of this Embodiment 3, uneven portions 252w are provided on the resin inner surface 252b of the resin inner portion 252 of the resin member 250. By forming the uneven portions 252w, the orientation of the glass fibers of the filler 58 contained in the resin inner portion 252 is disordered. Therefore, in the formed resin inner portion 252, the orientation of the glass fibers of the filler 58 is disordered, and in terms of the characteristics of the resin member 250, the anisotropy is small. In addition, parts identical to those in Embodiment 1 or 2 in Embodiment 3 have the same effects as those in Embodiment 1 or 2.

[0089] Next, a method for manufacturing the battery 200 will be described. In the present Embodiment 3, the terminal inner part 42 having the concavo-convex forming part 244w at the flange part 244 is used to perform the terminal forming process S1 to form the terminal component 40.

[0090] After that, in the insert molding process S2, a pair of resin components 250 are insert molded using the resin material 55 (refer to Figure 12 ). The molding die DE has the same upper die DA and lower die DC as those in Embodiment 2.

[0091] In the present Embodiment 3, a pair of inner part forming chambers FD for forming the resin inner part 252 of the resin component 250 are constituted by the lower die DC, the housing cover component 25, and the terminal component 40 having the concavo-convex forming part 244w. That is, the inner part forming surface FDn of the inner part forming chamber FD is formed by the inner forming surface DCn of the inner surface forming part DC1 of the lower die DC, the inner surface 25b of the housing cover component 25, the outer surface 244a and the outer peripheral surface 244d of the flange part 244 having the concavo-convex forming part 244w in the terminal inner part 42, and the lower outer peripheral surface 43e of the protruding part 43 of the terminal inner part 42.

[0092] In the insert molding process S2, if the molten resin 55M is injected into the inner part forming chamber FD from the gate GT, the flow of the molten resin 55M is disturbed by the concavo-convex forming part 244w provided on the outer surface 244a of the flange part 244, so that the orientation of the glass fibers of the filler 58 in the molten resin 55M is disturbed. Therefore, the resin component 250 is molded in a state where the orientation of the glass fibers of the filler 58 is disturbed.

[0093] In the method for manufacturing the battery 200 of the present Embodiment 3, in the insert molding process S2, the flow of the molten resin 55M is disturbed by the concavo-convex forming part 244w provided on the flange part 244 of the terminal inner part 42 of the terminal component 40, so that the direction of the glass fibers forming the filler 58 is disturbed. Therefore, the resin component 250 in which the orientation of the glass fibers forming the filler 58 is disturbed can be molded, and the battery 200 with less anisotropy in the characteristics of the resin component 250 can be manufactured. In addition, the same parts as those in Embodiment 1 or 2 have the same functions and effects as those in Embodiment 1 or 2.

[0094] As described above, the present invention has been described with reference to Embodiments 1 to 3, but the present disclosure is not limited to Embodiments 1 to 3. Of course, it can be appropriately modified and applied without departing from the gist thereof.

Claims

1. A power storage device, comprising: A housing member including an insertion through-hole; A terminal member inserted through the insertion through-hole of the housing member; and A resin member that insulates between the housing member and the terminal member and is hermetically joined to the housing member and the terminal member to fix the terminal member to the housing member, The resin member is formed of a resin material and is formed by insert molding. The resin material includes a thermoplastic main resin and a fibrous filler composed of a plurality of fibers, The power storage device is characterized in that The resin member has: A resin inner portion located inside the housing member; and A resin outer portion that passes through the insertion through-hole from the resin inner portion and extends to the outside of the housing member, On at least one of the resin inner surface facing the inside and the resin joint surface facing the outside and joined to the housing member in the resin inner portion, uneven portions are provided, By forming the uneven portions, the orientation of the fibers of the filler contained in the resin inner portion is disordered.

2. The power storage device according to claim 1, characterized in that The plurality of convex portions and concave portions forming the uneven portions are arranged in a staggered lattice pattern.

3. A method for manufacturing a power storage device, The power storage device includes: A housing member including an insertion through-hole; A terminal member inserted through the insertion through-hole of the housing member; and A resin member that insulates between the housing member and the terminal member and is hermetically joined to the housing member and the terminal member to fix the terminal member to the housing member, The resin member is formed of a resin material and is formed by insert molding. The resin material includes a thermoplastic main resin and a fibrous filler composed of a plurality of fibers, The resin member has: A resin inner portion located inside the housing member; and A resin outer portion that passes through the insertion through-hole from the resin inner portion and extends to the outside of the housing member, On at least one of the resin inner surface facing the inside and the resin joint surface facing the outside and joined to the housing member in the resin inner portion, uneven portions are provided, By forming the uneven portions, the orientation of the fibers of the filler contained in the resin inner portion is disordered, The method for manufacturing the power storage device is characterized in that An insert molding process is provided. In a state where the terminal member is inserted through the insertion through-hole of the housing member, the resin member is insert molded using the resin material, The insert molding process has the following processes, that is: A chamber forming process of forming a chamber for molding the resin member by a molding die, the housing member, and the terminal member; and An injection molding process of injecting a molten resin of the resin material into the chamber to fill the chamber with the molten resin to mold the resin member, The chamber has an outer portion forming chamber for forming the outer portion of the resin and an inner portion forming chamber for forming the inner portion of the resin. The inner portion forming surface forming the inner portion forming chamber has a concavo-convex forming portion for forming the concavo-convex portion. In the injection molding process, The flow of the molten resin is disturbed by the concavo-convex forming portion, so that the orientation of the fibers of the filler contained in the molten resin is disturbed, and the inner portion of the resin having the concavo-convex portion is formed.

4. The method for manufacturing an electric storage device according to claim 3, wherein The plurality of convex portions and concave portions forming the concavo-convex portion are arranged in a staggered lattice pattern. The plurality of convex portion forming portions and concave portion forming portions forming the concavo-convex forming portion are arranged in a staggered lattice pattern.

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