Clad structure and battery terminal component

Abstract

To provide a clad structure and a battery terminal component that has good productivity as a finished product, easily ensures bonding strength between aluminum and copper materials without requiring a diffusion reaction suppression layer made of Ni, and is expected to have long-term reliability even when used in batteries for automobiles, etc.SOLUTION: A clad structure includes a base, a wall extending upward from the outer edge of the upper surface of the base, a flange extending radially from the edge of the wall perpendicular to the wall, legs extending downward from the outer edge of the lower surface of the base, a first recess defined by the upper surface of the base and the inner wall surface of the wall, a second recess defined by the lower surface of the base and the inner leg surfaces of the legs, a first surface extending from the upper surface of the base via the inner wall surfaces of the wall to the upper flange surface of the flange made of an aluminum alloy material, and a second surface extending from the lower surface via the inner leg surface, lower leg surface, outer leg surface and outer wall to the lower flange surface made of a copper material, and an aluminum material containing 99% or more by mass of Al present between the aluminum alloy material and the copper material, and there is also provided a battery terminal part using the same.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a clad structure and a battery terminal part, and more particularly to a clad structure and a battery terminal part suitable for a negative electrode terminal electrically connected to the negative electrode side of a lithium ion secondary battery or the like. [Background technology]

[0002] Conventionally, aluminum-copper clad materials have been known that have a diffusion reaction suppression layer made of Ni (hereinafter referred to as "Ni layer") provided thereon to suppress a diffusion reaction between an aluminum material and a copper material due to heating. For example, Patent Document 1 discloses an aluminum-copper clad material in which an aluminum material and a copper material are pressure-welded with a thin Ni layer provided between them. Patent Document 1 also discloses that the clad material after pressure welding is subjected to diffusion annealing in order to increase the bonding strength between the aluminum layer, Ni layer, and copper layer.

[0003] Also, battery terminal components formed using an aluminum-copper clad material with a Ni layer are known. For example, Patent Document 2 discloses a cross-sectional structure (see FIG. 10 of the third embodiment) of a battery terminal component having a flange and a shaft, a T-shaped cross section along the shaft, and a Ni layer between an aluminum layer and a copper layer. Patent Document 2 also discloses that the effects of including the Ni layer include preventing the formation of brittle Al-Cu intermetallic compounds between the aluminum layer and the copper layer and preventing corrosion (galvanic corrosion) caused by direct contact between the aluminum layer and the copper layer. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-156995 [Patent Document 2] Patent No. 6581440 Summary of the Invention [Problem to be solved by the invention]

[0005] However, compared to structures without a Ni layer, aluminum-copper clad materials and battery terminal components made therefrom carry the risk of impairing various properties (e.g., electrical conductivity, thermal conductivity, ductility, and formability) due to the presence of the Ni layer. For example, the electrical conductivity (specific electrical resistivity) of Al is generally about 1.6 times that of Cu, and that of Ni is about 2.5 times that of Al. Furthermore, the thermal conductivity (thermal conductivity) of Al is generally about 0.6 times that of Cu, and that of Ni is about 2.6 times that of Al. Therefore, structures with a Ni layer may suffer from problems with reduced electrical conductivity and thermal conductivity. Furthermore, Ni is generally slightly harder than Cu, less ductile than Cu or Al, and highly adhesive, which can lead to problems with burrs and work hardening during molding.

[0006] One object of the present invention is to provide a clad structure and a battery terminal component that have good productivity as a finished product, that can easily ensure the bonding strength between an aluminum material and a copper material without having a diffusion reaction suppression layer made of Ni, and that can be expected to have long-term reliability even when used in batteries for automobiles, etc. [Means for solving the problem]

[0007] The cladding structure according to the present invention comprises a base portion having an upper bottom surface and a lower bottom surface, a wall portion having an inner wall surface and an outer wall surface extending upward from the outer edge of the upper bottom surface, upper and lower flange surfaces extending in a radial direction perpendicular to the wall portion from the end of the upwardly extending wall portion, a flange portion having an outer flange surface at the end extending in the radial direction, inner and outer leg surfaces extending downward from the outer edge of the lower bottom surface, and a leg portion having a lower leg surface at the end extending downward, which is defined by the upper bottom surface and the inner wall surfaces. and a second recess defined by the lower bottom surface and the inner leg surface, wherein a first surface extending from the upper bottom surface, via the inner wall surface, to the upper flange surface is made of an aluminum alloy material, and a second surface extending from the lower bottom surface, via the inner leg surface, the lower leg surface, the outer leg surface, and the outer wall portion, to the lower flange surface is made of a copper material, and an aluminum material containing 99% or more by mass of Al is present between the aluminum alloy material and the copper material.

[0008] In the cladding structure of the present invention, the inner wall surface of the wall portion preferably comprises a vertical wall surface extending upward from the upper bottom surface of the base portion and an inclined wall surface connecting from the vertical wall surface to the upper flange surface of the flange portion.

[0009] In the cladding structure according to the present invention, preferably, the outer flange surface of the flange portion has a boundary between the first surface continuing from the upper flange surface and the second surface continuing from the lower flange surface.

[0010] The clad structure having the above-mentioned configuration is suitable for use as a battery terminal part.

[0011] The battery terminal part of the present invention comprises a base portion having an upper bottom surface and a lower bottom surface, a wall portion having inner and outer wall surfaces extending upward from the outer edge of the upper bottom surface, upper and lower flange surfaces extending radially from the end of the upwardly extending wall portion perpendicular to the wall portion, a flange portion having an outer flange surface at the end extending radially, inner and outer leg surfaces extending downward from the outer edge of the lower bottom surface and a lower leg surface at the end extending downward, and a first recess defined by the upper bottom surface and the inner wall surfaces, The clad structure has a second recess defined by the lower bottom surface and the inner leg surface, and a first surface extending from the upper bottom surface, via the inner wall surface, to the upper flange surface is made of an aluminum alloy material, and a second surface extending from the lower bottom surface, via the inner leg surface, the lower leg surface, the outer leg surface, and the outer wall portion, to the lower flange surface is made of a copper material, and an aluminum material containing 99% or more by mass of Al is present between the aluminum alloy material and the copper material.

[0012] In the battery terminal part of the present invention, preferably, the inner wall surface of the wall portion is composed of a vertical wall surface extending upward from the upper bottom surface of the base portion and an inclined wall surface connecting from the vertical wall surface to the upper flange surface of the flange portion.

[0013] In the battery terminal part according to the present invention, preferably, the outer flange surface of the flange portion has a boundary between the first surface continuing from the upper flange surface and the second surface continuing from the lower flange surface. [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a clad structure and a battery terminal component that have good productivity as a finished product, that can easily ensure the bonding strength between an aluminum material and a copper material without having a diffusion reaction suppression layer made of Ni, and that can be expected to have long-term reliability even when used in batteries for automobiles, etc. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a diagram showing an example of an embodiment of a cladding structure according to the present invention; [Figure 2]FIG. 2 is a flow chart showing an example of a method for manufacturing a cladding structure according to the present invention. [Figure 3] FIG. 10 is a diagram showing an example of a clad piece prepared in a material preparation step. [Figure 4] FIG. 2 is a diagram showing an example of a first molded body molded in a first molding step. [Figure 5] FIG. 4 is a diagram showing an example of a second molded body molded in a second molding step. [Figure 6] FIG. 10 is a diagram showing an example of a third molded body molded in a third molding step. [Figure 7] FIG. 1 is a diagram showing an example of a negative electrode side terminal connection structure in which a clad structure is used as a battery terminal component to electrically connect a negative electrode side component of one battery to a connection component connected to another battery. [Figure 8] 8 is a diagram showing an example of a terminal connection structure in which the negative electrode side component of the battery is different from that illustrated in FIG. 7. DETAILED DESCRIPTION OF THE INVENTION

[0016] The cladding structure according to the present invention will be described below by taking examples of configurations that are considered to be preferred embodiments and referring to the drawings as appropriate.

[0017] 1 shows the configuration of one example of an embodiment of a clad structure 1 according to the present invention. The clad structure 1 is particularly suitable for battery components that require weight reduction while maintaining electrical properties, and is suitable, for example, for a terminal component (battery terminal component 1) for electrically connecting a negative electrode component of a battery to a connecting component (bus bar) between the batteries.

[0018] As shown in Fig. 1, the clad structure 1 (battery terminal component 1) includes a base portion 10, a wall portion 11, a flange portion 12, a leg portion 13, a first recess 14, and a second recess 15. The clad structure 1 (battery terminal component 1) is a molded body obtained by plastically deforming a clad plate according to its respective portions. A method for manufacturing a molded body by plastically deforming a clad plate according to its respective portions will be described later.

[0019] The base portion 10 has an upper surface 10A and a lower surface 10B. The base portion 10 is composed of an upper (Z1 side) aluminum layer 16 and a lower (Z2 side) copper layer 17. The aluminum layer 16 constituting the base portion 10 is composed of an upper (Z1 side) aluminum alloy layer 16b and a lower (Z2 side) pure aluminum layer 16a. Therefore, the upper surface 10A is the surface of the aluminum alloy layer 16b, and the lower surface 10B is the surface of the copper layer 17, with the pure aluminum layer 16a existing between the upper surface 10A and the lower surface 10B. The aluminum alloy layer 16b, the pure aluminum layer 16a, and the copper layer 17 constituting the base portion 10 are pressure-welded to each other in the thickness direction (Z direction) in this order, and are thermally diffusion bonded at the pressure-welded interface, after which they are plastically deformed accordingly. When the legs 13 are formed from the original shape of the base 10, the copper layer 17 of the original shape of the base 10 is plastically deformed to a large extent.

[0020] 1, the base 10 does not need to have a through-hole connecting the first recess 14 and the second recess 15 in the Z direction. Because the base 10 does not have a through-hole in the Z direction, even if the electrolyte leaks from inside the battery to the terminal connection part on the negative electrode side, the electrolyte can be blocked within the second recess 15. This prevents the electrolyte from leaking out of the battery through the terminal connection part on the negative electrode side.

[0021] The upper surface 10A of the base portion 10 is included in the surface that constitutes the first surface made of an aluminum alloy material, and can be made of approximately the same aluminum alloy material (aluminum alloy layer 16b) as the connection part 3 (see FIGS. 7 and 8) made of pure aluminum or an aluminum alloy material. Therefore, because the upper surface 10A of the base portion 10 is made of approximately the same aluminum alloy material as the connection part 3, even when a terminal connection structure 3 (not shown) is adopted in which the upper surface 10A contacts the connection part, an increase in electrical resistance at the contact interface between the upper surface 10A and the connection part 3 is suppressed, and good conductivity can be ensured between the base portion 10 and the connection part 3.

[0022] Furthermore, the lower bottom surface 10B of the base portion 10 is included in the surface constituting the second surface made of copper material, and can be made of substantially the same copper material (copper layer 17) as the negative electrode side component 2 (see FIGS. 7 and 8) made of copper material. Therefore, since the lower bottom surface 10B of the base portion 10 is made of substantially the same copper material as the negative electrode side component 2, even when a terminal connection structure (see FIG. 7) in which the lower bottom surface 10B and the negative electrode side component 2 contact each other is adopted, an increase in electrical resistance at the contact interface between the lower bottom surface 10B and the negative electrode side component 2 is suppressed, and good conductivity can be ensured between the base portion 10 and the negative electrode side component 2.

[0023] The wall portion 11 has an inner wall surface 11A and an outer wall surface 11B extending upward (toward the Z1 side) from the outer edge of the upper bottom surface 10A. The wall portion 11 is composed of an aluminum layer 16 on the inner wall surface 11A side and a copper layer 17 on the outer wall surface 11B side. The aluminum layer 16 constituting the wall portion 11 is composed of an aluminum alloy layer 16b on the inner wall surface 11A side and a pure aluminum layer 16a on the copper layer 17 side. Therefore, the inner wall surface 11A is the surface of the aluminum alloy layer 16b, the outer wall surface 11B is the surface of the copper layer 17, and the pure aluminum layer 16a is between the inner wall surface 11A and the outer wall surface 11B. The aluminum alloy layer 16b, the pure aluminum layer 16a, and the copper layer 17 constituting the wall portion 11 are pressure-welded to each other in the thickness direction (X direction) in this order, and are thermally diffusion-bonded at the pressure-welded interface, followed by corresponding plastic deformation.

[0024] The inner wall surface 11A of the wall portion 11 is included in the surface that constitutes the first surface made of aluminum alloy material, and can be made of approximately the same aluminum alloy material (aluminum alloy layer 16b) as the connection part 3 (see FIGS. 7 and 8) made of pure aluminum or aluminum alloy material. Therefore, even when a terminal connection structure (not shown) is adopted in which the inner wall surface 11A and the connection part 3 come into contact with each other, the inner wall surface 11A of the wall portion 11 is made of approximately the same aluminum alloy material as the connection part 3, so that an increase in electrical resistance at the contact interface between them is suppressed, and good conductivity can be ensured between the wall portion 11 and the connection part 3.

[0025] Furthermore, the outer wall surface 11B of the wall 11 is included in the surface that constitutes the second surface made of copper, and can be made of substantially the same copper material (copper layer 17) as the negative electrode side component 2 (see FIGS. 7 and 8) made of copper. Therefore, even when a terminal connection structure (see FIG. 8) is adopted in which the outer wall surface 11B of the wall 11 is in contact with the negative electrode side component 2, an increase in electrical resistance at the contact interface between them is suppressed, and good conductivity can be ensured between the wall 11 and the connection component 3.

[0026] The flange 12 has an upper flange surface 12A and a lower flange surface 12B that extend radially (in the X direction) from the end (Z1 side) of the wall 11 extending upward (toward the Z1 side), perpendicular to the wall 11. The flange 12 further has an outer flange surface 12C at the end extending in the radial direction (in the X direction). The flange 12 is composed of an aluminum layer 16 on the upper side (Z1 side) and a copper layer 17 on the lower side (Z2 side). The aluminum layer 16 that constitutes the flange 12 is composed of an aluminum alloy layer 16b on the upper side (Z1 side) and a pure aluminum layer 16a on the lower side (Z2 side). Therefore, the upper rib surface 12A is the surface of the aluminum alloy layer 16b, and the lower rib surface 12B is the surface of the copper layer 17, with the pure aluminum layer 16a existing between the upper rib surface 12A and the lower rib surface 12B. Furthermore, at the outer rib surface 12C, the surface of the aluminum alloy layer 16b continues from the upper rib surface 12A, and the surface of the copper layer 17 continues from the lower rib surface 12B. The pure aluminum layer 16a exists between the aluminum alloy layer 16b continuing from the upper rib surface 12A and the copper layer 17 continuing from the lower rib surface 12B. Therefore, at the outer rib surface 12C, there are boundaries between the aluminum alloy layer 16b and the pure aluminum layer 16a, and between the pure aluminum layer 16a and the copper layer 17. The aluminum alloy layer 16b, pure aluminum layer 16a, and copper layer 17 that make up the flange portion 12 are pressure-welded in this order in the thickness direction (Z direction) of each other, and are thermally diffusion bonded at the pressure-welded interface, after which they are plastically deformed accordingly.

[0027] Upper flange surface 12A of flange portion 12 is included in the surface that constitutes the first surface made of aluminum alloy material, and can be made of approximately the same aluminum alloy material (aluminum alloy layer 16b) as connecting part 3 (see FIGS. 7 and 8) made of pure aluminum or aluminum alloy material. Therefore, because upper flange surface 12A of flange portion 12 is made of approximately the same aluminum alloy material as connecting part 3, even when a terminal connection structure (see FIGS. 7 and 8) in which upper flange surface 12A and connecting part 3 contact each other is adopted, an increase in electrical resistance at the contact interface between them is suppressed, and good conductivity can be ensured between flange 12 and connecting part 3. can.

[0028] Furthermore, the lower flange surface 12B of the flange portion 12 is included in the surface that constitutes the second surface made of copper, and can be made of substantially the same copper material (copper layer 17) as the negative electrode side component 2 (see FIGS. 7 and 8) made of copper. Therefore, even when a terminal connection structure is adopted in which the lower flange surface 12B and the negative electrode side component 2 come into contact with each other (such as when the seal 4 shown in FIG. 8 is not used), the lower flange surface 12B of the flange portion 12 is made of substantially the same copper material as the negative electrode side component 2, and therefore an increase in electrical resistance at the contact interface between them is suppressed, and good conductivity can be ensured between the flange portion 12 and the connection component 3.

[0029] The leg portion 13 has an inner leg surface 13A and an outer leg surface 13B extending downward (toward Z2) from the outer edge of the lower base surface 10B. The leg portion 13 further has a lower leg surface 13C at the end extending downward (toward Z2). The inner leg surface 13A, the outer leg surface 13B, and the lower leg surface 13C of the leg portion 13 are all formed by the copper layer 17. That is, the leg portion 13 is formed by the copper layer 17. Therefore, the inner leg surface 13A, the outer leg surface 13B, and the lower leg surface 13C are the surfaces of the copper layer 17. The copper layer 17 forming the leg portion 13 is significantly plastically deformed when it is formed from the original shape of the base portion 10 after being affected by the heating during the above-mentioned thermal diffusion bonding.

[0030] The inner wall surface 13A, the outer wall surface 13B, and the lower leg surface 13C of the leg 13 are included in the surface that constitutes the second surface made of copper, and can be made of substantially the same copper material (copper layer 17) as the negative-electrode-side component 2 (see FIGS. 7 and 8) made of copper. Therefore, even when a terminal connection structure (see FIG. 8) is adopted in which one or more of the inner wall surface 13A, the outer wall surface 13B, and the lower leg surface 13C contact the negative-electrode-side component 2, an increase in electrical resistance at the contact interface between the two is suppressed, and good conductivity can be ensured between the leg 13 and the connection component 3.

[0031] The first recess 14 is defined by an upper bottom surface 10A of the base 10 and an inner wall surface 11A of the wall 11. This first recess 14 can be used to electrically connect the clad structure 1 (battery terminal component 1) to a connection component 3 (see FIGS. 7 and 8) that is electrically connected to another battery. For example, a fitting structure (not shown) that inserts and fits the connection component 3 into this first recess 14 can easily and stably electrically connect the clad structure 1 (battery terminal component 1) to the connection component 3.

[0032] As described above, the upper surface 10A of the base 10 and the inner wall surface 11A of the wall 11, which define the first recess 14, are the surfaces of the aluminum alloy layer 16b. Therefore, the surface of the first recess 14 is the surface of the aluminum alloy layer 16b. Furthermore, the surface of the first recess 14 is included in the surface that constitutes the first surface made of aluminum alloy material, and can be made of approximately the same aluminum alloy material (aluminum alloy layer 16b) as the connection part 3 (see FIGS. 7 and 8 ) made of pure aluminum or aluminum alloy material. Because the surface of the first recess 14 is the surface of the aluminum alloy layer 16b, even when a terminal connection structure (not shown) in which the first recess 14 and the connection part 3 contact each other is adopted, an increase in electrical resistance at the contact interface between them is suppressed, thereby ensuring good conductivity between the flange 12 and the connection part 3.

[0033] The second recess 15 is defined by the lower bottom surface 10B of the base 10 and the inner leg surface 13A of the leg 13. This second recess 15 can be used to electrically connect the clad structure 1 (battery terminal component 1) and the negative electrode side component 2 of the battery (see FIGS. 7 and 8). For example, a fitting structure (see FIG. 7) in which the negative electrode side component 2 is inserted and fitted into this second recess 14 can easily and stably electrically connect the clad structure 1 (battery terminal component 1) and the negative electrode side component 2.

[0034] As described above, the lower bottom surface 10B of the base portion 10 and the leg wall surface 13A of the leg portion 13, which define the second recess 15, are the surfaces of the copper layer 17. Therefore, the surface of the second recess 15 is the surface of the copper layer 17. Furthermore, the surface of the second recess 15 is included in the surface that constitutes the second surface made of copper material, and can be made of substantially the same copper material (copper layer 17) as the negative electrode side component 2 (see FIGS. 7 and 8) made of copper material. Because the surface of the second recess 15 is the surface of the copper layer 17, even when a terminal connection structure (see FIG. 7) in which the second recess 15 and the negative electrode side component 2 contact each other is adopted, an increase in electrical resistance at the contact interface between them is suppressed, thereby ensuring good conductivity between the second recess 15 and the negative electrode side component 2.

[0035] As described above, the clad structure 1 (battery terminal component 1) has a surface region of the aluminum alloy layer 16b that extends from the upper bottom surface 10A of the base portion 10, through the inner wall surface 11A of the wall portion 11, to the upper flange surface 12A of the flange portion 12. This surface region of the aluminum alloy layer 16b is referred to as the first surface. As shown in FIG. 1 , this first surface occupies most of the surface of the aluminum alloy layer 16b.

[0036] As described above, the clad structure 1 (battery terminal component 1) has a surface region of the copper layer 17 that extends from the lower bottom surface 10B of the base portion 10, through the inner leg surface 13A, the lower leg surface 13C, the outer leg surface 13B, and the outer wall surface 11B of the wall portion 11, to the lower flange surface 12C of the flange portion 12. This surface region of the copper layer 17 is referred to as the second surface. As shown in FIG. 1 , this second surface occupies most of the surface of the copper layer 17.

[0037] The aluminum layer 16 located on the upper side (Z1 side) of the clad structure 1 (battery terminal component 1) is made of an aluminum material. This aluminum layer 16 is composed of a pure aluminum layer 116a made of a pure aluminum material containing 99 mass % or more of Al, and an aluminum alloy layer 16b made of an aluminum alloy material.

[0038] Here, in the clad structure 1 (battery terminal component 1), the aluminum alloy layer 16b, the pure aluminum layer 16a, and the copper layer 17 have substantially laminar diffusion regions (hereinafter referred to as "diffusion layers") formed by a thermal diffusion reaction at the pressure-welded interfaces in the thickness direction (Z direction) between the layers. The average thickness of the diffusion layers between the layers is significantly smaller than that of the other three layers. For example, the diffusion layer formed between the pure aluminum layer 16a and the copper layer 17 is thought to have an average thickness of approximately 0.5 μm to 10 μm.

[0039] Within the diffusion layer between the pure aluminum layer 16a and the copper layer 17, an extremely thin, discontinuous oxide film made of aluminum oxide exists along the bonding interface between the diffusion layer and the pure aluminum layer 16a and the bonding interface between the diffusion layer and the copper layer 17. This discontinuous oxide film is believed to originate from a natural oxide film formed on the surface of the pure aluminum plate that constitutes the pure aluminum layer 16a. Even if the oxide film on the surface of the pure aluminum plate is removed by polishing or the like, it immediately regenerates upon exposure to the air. Therefore, a continuous oxide film exists on the surface of the pure aluminum plate immediately before pressure welding (clad rolling).

[0040] During pressure welding (clad rolling), the oxide film on the surface of the pure aluminum sheet is broken up and dispersed, becoming discontinuous, due to the large plastic deformation of the pure aluminum sheet. Immediately after pressure welding (clad rolling), the surface of the pure aluminum sheet (layer) is not exposed to the air, so the broken up and dispersed oxide film remains. During diffusion annealing, Al-Cu intermetallic compounds are formed near the pressure-welded interface between the pure aluminum layer and the copper layer through a thermal diffusion reaction. These Al-Cu intermetallic compounds are thought to be fine and randomly oriented. The random growth of these fine intermetallic compounds further breaks up and disperses the discontinuous oxide film. As a result, many gaps form in the oxide film, increasing the opportunities for direct contact between the pure aluminum and copper. This facilitates the formation of Al-Cu intermetallic compounds, leading to the proper formation of the intermetallic compound layer (diffusion layer), and ultimately to the achievement of optimal diffusion bonding strength between the pure aluminum layer and the copper layer.

[0041] In the clad structure 1 (battery terminal component 1) shown in FIG. 1 , the aluminum layer 16 is composed of a pure aluminum layer 16a and an aluminum alloy layer 16b. The aluminum layer 16, which is composed of the pure aluminum layer 16a and the aluminum alloy layer 16b, has a simple structure in which the pure aluminum layer 16a and the aluminum alloy layer 16b are made of a homogeneous Al-based metallic material, making it easily practical. Because the pure aluminum layer 16a and the aluminum alloy layer 16b are made of a homogeneous Al-based metallic material, a homogeneous, approximately layered diffusion region (hereinafter referred to as a "diffusion layer") is formed between the pure aluminum layer 16a and the aluminum alloy layer 16b by the thermal diffusion reaction (self-diffusion) of Al. This homogeneous diffusion layer ensures adequate bonding strength between the pure aluminum layer 16a and the aluminum alloy layer 16b. Furthermore, if the pure aluminum layer 16a is substantially free of alloying elements or impurity elements, the thermal diffusion reaction between Al and Cu occurs appropriately between the pure aluminum layer 16a and the copper layer 17, as described above. Therefore, an intermetallic compound layer (diffusion layer) made of an Al-Cu based intermetallic compound is properly formed between the pure aluminum layer 16a and the copper layer 17. Therefore, by employing the aluminum layer 16 made up of the pure aluminum layer 16a and the aluminum alloy layer 16b, a clad structure (battery terminal component) without a nickel layer can be properly formed.

[0042] Furthermore, by configuring the aluminum layer 16 with the pure aluminum layer 16a and the aluminum alloy layer 16b, the properties of the pure aluminum layer 16a (electrical conductivity, thermal conductivity, formability, workability, weldability, etc.) can be efficiently utilized. At the same time, the properties of the aluminum alloy layer 16b (mechanical properties such as tensile strength, yield strength, and hardness, ductility, formability, workability, weldability, etc.) can be efficiently utilized. Furthermore, compared to a layer structure of a nickel layer and a pure aluminum layer or a layer structure of a nickel layer and an aluminum alloy layer, the difference between the nickel and aluminum-based materials results in a reduced specific electrical resistance of the clad material (improved electrical conductivity), an increased thermal conductivity (improved thermal conductivity), and improved formability and workability.

[0043] In the clad structure 1 (battery terminal component 1) shown in FIG. 1 , the pure aluminum layer 16a is made of an aluminum material containing 99% or more by mass of Al. Aluminum materials containing 99% or more by mass are composed of non-heat-treatable aluminum alloys, such as the JIS A1000 series, but this composition is generally classified as pure aluminum. Pure aluminum has better malleability than pure nickel and is suitable for rolling and press processing, which cause plastic deformation by compressive force. Therefore, a pure aluminum sheet made of pure aluminum can be easily pressure-bonded to both a copper sheet and an aluminum alloy sheet by clad rolling. Furthermore, pure aluminum has a lower hardness and work-hardening coefficient (n value) than aluminum alloys and pure copper. Therefore, a pure aluminum sheet made of pure aluminum experiences a relatively small degree of work hardening during pressure welding (clad rolling), allowing it to be smoothly spread between the aluminum alloy sheet and the copper sheet. As a result, the pure aluminum layer 16a can be easily pressure-bonded to both the aluminum alloy layer 16b and the copper layer 17.

[0044] The pure aluminum material suitable for the pure aluminum layer 16a is preferably made of JIS A1000 series or pure aluminum with a composition similar thereto, taking into consideration mechanical properties such as tensile strength, yield strength, elongation, and hardness, as well as electrical conductivity, thermal conductivity, ductility, formability, workability, and weldability. For example, A1050, A1070, A1080, A1085, A1100, and A1200 may be used, which have good electrical conductivity, thermal conductivity, formability, workability, and weldability.

[0045] In the clad structure 1 (battery terminal component 1) shown in FIG. 1, the aluminum alloy layer 16b is made of an aluminum alloy. Compared to pure aluminum, aluminum alloys have excellent mechanical properties, particularly tensile strength, yield strength, and hardness. These unique properties of aluminum alloys can be utilized by forming the aluminum alloy layer 16b from an aluminum alloy. Furthermore, by forming the clad structure 1 (battery terminal component 1) so that the aluminum alloy layer 16b using an aluminum alloy with desired properties is dominant, it is possible to impart the desired properties attributable to the aluminum alloy to the clad structure 1 (battery terminal component 1). For example, by using aluminum alloys such as A3003 and A5052 (described below), it is possible to form a clad structure 1 (battery terminal component 1) including an aluminum alloy layer 16b with excellent mechanical properties, ductility, formability, processability, and weldability.

[0046] The aluminum alloy material suitable for the aluminum alloy layer 16b is preferably a non-heat-treatable aluminum alloy, from the viewpoint of obtaining the pressure bonding strength between the aluminum alloy layer 16a and the pure aluminum layer 16a by pressure welding and the diffusion bonding strength by diffusion annealing. Non-heat-treatable aluminum alloys are alloys that obtain their specified strength mainly through cold working, such as rolling, such as the JIS A3000 series, A4000 series, and A5000 series. On the other hand, heat-treatable aluminum alloys are alloys that obtain their specified strength through heat treatment, such as quenching and tempering, such as the JIS A2000 series, A6000 series, and A7000 series. Note that the JIS A1000 series and alloys with compositions similar thereto, which belong to the non-heat-treatable aluminum alloys, are treated as pure aluminum, as described above.

[0047] Non-heat-treatable aluminum alloys suitable for the aluminum alloy layer 16b are those with compositions similar to those specified by the JIS A3000 and A5000 series, taking into consideration mechanical properties such as tensile strength, yield strength, elongation, and hardness, as well as electrical conductivity, thermal conductivity, ductility, formability, workability, and weldability. Examples include A3003, A3103, A3203, A5005, A5052, A5154, and A5454, which offer excellent mechanical properties, ductility, formability, workability, and weldability. Other suitable alloys include A3004, A3104, A3105, A5021, A5042, A5082, and A5182, which offer excellent mechanical properties, ductility, formability, and workability. Other suitable alloys include A5083 and A5086, which offer excellent mechanical properties and weldability.

[0048] In the clad structure 1 (battery terminal component 1) shown in FIG. 1 , the copper layer 17 is preferably made of copper containing 98% or more by mass of Cu. Copper containing 98% or more by mass of Cu is generally classified as pure copper. Pure copper contains 98% or more by mass of Cu, which has low specific electrical resistance and high thermal conductivity, and therefore has excellent electrical and thermal conductivity. These properties unique to pure copper can be utilized by constructing the copper layer 17 from pure copper. Furthermore, by constructing the clad structure 1 (battery terminal component 1) so that the copper layer 17 using pure copper with desired properties is dominant, it is possible to impart the desired properties attributable to pure copper to the clad structure 1 (battery terminal component 1). For example, by using C1020 or C1100, described below, it is possible to construct a clad structure 1 (battery terminal component 1) including a copper layer 17 with excellent mechanical properties, electrical conductivity, thermal conductivity, ductility, formability, workability, and weldability.

[0049] The copper material suitable for the copper layer 17 is preferably a pure copper material of the JIS C1000 series or a material with a similar composition (e.g., C1020, C1100, C1201, C1220, C1441, C1510, C1921, or C1940), taking into consideration mechanical properties such as tensile strength, yield strength, elongation, and hardness, as well as electrical conductivity, thermal conductivity, ductility, formability, workability, and weldability.

[0050] The copper layer 17 located on the lower side (Z2 side) of the clad structure 1 (battery terminal component 1) is made of a copper material. This copper material may be a JIS C1000 series (C1020, C1100, etc.) copper alloy with excellent ductility and drawing workability, or a material with a similar composition (pure copper). This copper material may also be a JIS C2000 series (C2600, C2680, etc.) copper alloy with excellent ductility and drawing workability, a JIS C7000 series (C7250, etc.) copper alloy with a similar composition (copper alloy). For example, when high electrical conductivity is important, pure copper is preferably selected. When tensile strength and yield strength are important, a copper alloy is preferably selected.

[0051] Next, a manufacturing method of the clad structure 1 shown in Fig. 1 will be described with reference to a preferred manufacturing process diagram (flow chart) and appropriate drawings. Note that a battery terminal component constructed using the clad structure 1 may be constructed using the clad structure 1 as is, as in the above-described battery terminal component 1, or may be constructed by performing minor processing on the clad structure 1, so this can be handled as needed.

[0052] 2 shows a manufacturing process diagram (flow chart) of the clad structure 1 (battery terminal component 1). This manufacturing process includes, as main steps, a material preparation step, a first molding step, a second molding step, and a third molding step, and also includes, as an optional step, a fourth molding step, as needed.

[0053] <Material preparation process> The material preparation step is a step of preparing a clad piece 100 as shown in FIG. 3 using a clad plate as a material, as shown in FIG. 2. The clad piece 100, which serves as the starting material for forming the clad structure 1, is a small piece of clad plate composed of an aluminum layer 116 made of an aluminum material and a copper layer 117 made of a copper material. In detail, the aluminum layer 16 constituting the clad piece 100 is composed of an aluminum alloy layer 116b made of an aluminum alloy material located on the outer side (Z1 side), and a pure aluminum layer 116a made of a pure aluminum material containing 99% or more by mass of Al located on the copper layer 117 side (Z2 side) of the aluminum alloy layer 116b. Therefore, the clad piece 100 is a small piece of clad plate with a three-layer structure composed of the aluminum alloy layer 116b, the pure aluminum layer 116a, and the copper layer 117. The clad piece 100 can be formed by using a clad plate having substantially the same layer structure as the clad piece 100 and processing means such as punching or wire cutting.

[0054] The pure aluminum layer 116a, aluminum alloy layer 116b, and copper layer 117 constituting the clad piece 100 may be designed taking into consideration the shapes and volumes of the pure aluminum layer 11a, aluminum alloy layer 16b, and copper layer 17 of the clad structure 1 (battery terminal component 1) that will be the finished product. The pure aluminum layer 116a constituting the clad piece 100 is designed taking into consideration the desired bonding strength between the aluminum alloy layer 116b and the copper layer 117. It is preferable that the pure aluminum layer 116a in the clad piece 100 is formed as a single continuous layer, as this facilitates the desired bonding strength, but it does not have to be formed as a single continuous layer. The pure aluminum layer 116a in the clad piece 100 may have, for example, multiple evenly distributed cracks where the aluminum alloy layer 116b and the copper layer 117 come into contact with each other to the extent that the desired bonding strength is achieved.

[0055] The clad plate (not shown) that serves as the material for the clad piece 100 is made by laminating a suitably tempered aluminum alloy plate, a pure aluminum plate containing 99% or more by mass of Al, and a copper plate in this order in the thickness direction (Z direction) and pressing them together (clad rolling), followed by a moderate heating and diffusion reaction at the pressed-welded interface. The aluminum alloy plate that constitutes the clad plate is the material that constitutes the aluminum alloy layer 16b of the clad structure 1 (battery terminal component 1). The pure aluminum plate that constitutes the clad plate is the material that constitutes the pure aluminum layer 16a of the clad structure 1 (battery terminal component 1). The copper plate that constitutes the clad plate is the material that constitutes the copper layer 17 of the clad structure 1 (battery terminal component 1).

[0056] <1st molding process> The first molding step is a step of forming a first molded body 200 as shown in FIG. 4 using a clad piece 100 as shown in FIG. 2. In the first molding step, a general press molding method is used to mainly mold a base portion 210, a wall portion 211, and a flange portion 212, which are the original shapes of the base portion 10, the wall portion 11, and the flange portion 12 shown in FIG. 1. During this process, the clad piece 100 is plastically deformed to correspond to the shapes of each portion of the first molded body 200, which is the target shape. As a result, the first molded body 200 includes the base portion 210, the wall portion 211, the flange portion 212, and a first recess 214, as shown in FIG. 4. The base portion 210, the wall portion 211, the flange portion 212, and the first recess 214 of the first molded body 200 correspond to the base portion 10, the wall portion 11, the flange portion 12, and the first recess 14 of the clad structure 1. In this first molded body 200, the aluminum alloy layer 216b located on the upper side (Z1 side) extends inside the first recess 214, the copper layer 217 located on the lower side (Z2 side) extends outside the first recess 214, and the pure aluminum layer 216a located between the aluminum alloy layer 216b and the copper layer 217 extends inside the first recess 214.

[0057] <Second forming process> The second forming step is a step of forming a second formed body 300 as shown in FIG. 5 using a first formed body 200 as shown in FIG. 2. In the second forming step, a general press forming method is used to form mainly wall portions 311 and flange portions 312, which are the original shapes of the wall portions 11 and flange portions 12 shown in FIG. 1, and also to form a base portion 310, in which the thickness (length in the Z direction) of the copper layer 317 is large. The large thickness of the copper layer 317 that constitutes the base portion 310 ensures that there is copper material (copper layer 17) for forming the leg portions 13 shown in FIG. 1. During this process, the first formed body 200 is plastically deformed to correspond to the shapes of each portion of the second formed body 300, which is the target shape. 5, the second compact 300 includes a base 210, a wall 211, a flange 212, and a first recess 214, which are the original shapes of the base 10, the wall 11, the flange 12, and the first recess 14 of the cladding structure 1. The second compact 300 also includes the base 310 having a thick copper layer 317 necessary for forming the leg 13 and the second recess 15 of the cladding structure 1 in the next step. In the second compact 300, the aluminum alloy layer 316b located on the upper side (Z1 side) extends inside the first recess 314, the copper layer 317 located on the lower side (Z2 side) extends outside the first recess 314, and the pure aluminum layer 316a located between the aluminum alloy layer 316b and the copper layer 317 extends inside the first recess 314.

[0058] <Third molding process> The third molding step is a step of forming a third molded body 400 as shown in FIG. 6 using a second molded body 300, as shown in FIG. 2. In the third molding step, a general press molding method is used to plastically deform the base 310 and wall 311 of the second molded body 300 to form a base 410, leg 413, and second recess 415, which correspond to the base 10, leg 13, and second recess 15 shown in FIG. 1. During this process, the second molded body 300 is plastically deformed to correspond to the shapes of each portion of the third molded body 400, which is the target shape. This completes the base 410, wall 411, flange 412, and leg 413, which substantially correspond to the base 10, wall 11, flange 12, and leg 13 shown in FIG. 1. Furthermore, a first recess 414 and a second recess 415, which substantially correspond to the first recess 14 and the second recess 15, are defined. Also, a first surface and a second surface of the third molded body 400 that substantially correspond to the first surface and the second surface of the clad structure 1 (battery terminal component 1) are obtained.

[0059] The third molded body 400 can have a shape substantially identical to the base portion 10, wall portion 11, flange portion 12, leg portion 13, first recess 14, and second recess 15 of the cladding structure 1. As shown in FIG. 6 , the third molded body 400 includes a base portion 410, wall portion 411, flange portion 412, leg portion 413, first recess 414, and second recess 415. In the third molded body 400, the aluminum alloy layer 416b located on the upper side (Z1 side) extends inside the first recess 414, the copper layer 417 located on the lower side (Z2 side) extends outside the first recess 414, and the pure aluminum layer 416a located between the aluminum alloy layer 416b and the copper layer 417 extends inside the first recess 414. As a result, the first surface where the aluminum alloy layer 416b of the third molded body 400 is exposed and the second surface where the copper layer 417 is exposed correspond to the first surface and second surface of the clad structure 1 (battery terminal component 1).

[0060] As a result, the third molded body 400 becomes a finished product if it passes a predetermined inspection after, for example, surface cleaning to remove contaminants (metal powder, dirty oil, dust, etc. resulting from molding). This finished product is the clad structure 1 (battery terminal component 1). Note that, for example, if the flange portion 412 of the third molded body 400 is long in the X direction (has excess thickness), a fourth molding step shown in FIG. 2 can be added.

[0061] <4th molding process> In the fourth molding step, when the flange 412 of the third molded body 400 is long in the X direction (has excess thickness), the outer flange surface 412C is partially removed by a general press molding method (trimming molding method) to mold it into a predetermined shape. In the fourth molding step, the outer flange surface 412C of the flange 412 of the third molded body 400 is trimmed to obtain a shape similar to the outer flange surface 12C of the flange 12 of the cladding structure 1. The fourth molded body (not shown) obtained in the fourth molding step is then subjected to the surface cleaning and inspection described above to become a finished product. This finished product is the cladding structure 1 (battery terminal component 1).

[0062] As described above, the clad structure 1 (battery terminal component 1) according to the present invention can be manufactured by a simple press-forming method shown in the manufacturing process diagram (flow chart) of FIG. 2 . In the manufacturing process shown in FIG. 2 , the clad structure 1 (battery terminal component 1) can be obtained starting from a clad piece 100 made of a three-layer clad plate composed of an aluminum alloy layer, a pure aluminum layer, and a copper layer. The clad plate from which the clad piece 100 is made can be easily manufactured by a typical clad plate manufacturing method involving rolling (clad rolling) of dissimilar metals and diffusion annealing. A clad plate that has undergone appropriate rolling (clad rolling) and diffusion annealing has the aluminum alloy layer, pure aluminum layer, and copper layer properly thermally diffusion bonded, providing sufficient bonding strength to prevent peeling between the layers. Therefore, when the clad plate is used to form the clad piece 100, the aluminum alloy layer 116 b, pure aluminum layer 116 a, and copper layer 117 of the clad piece 100 do not easily peel off. By using the clad plate as the starting material for the clad piece 100, the clad piece 100 can adequately withstand the plastic deformation described above, and the aluminum alloy layer 16b, pure aluminum layer 16a, and copper layer 17 that make up the clad structure 1 (battery terminal component 1) do not easily peel off.

[0063] Therefore, the clad structure 1 according to the present invention can use the clad piece 100 made from a clad plate as a starting material. From this perspective, productivity as a finished product can be expected, and it is easy to ensure the bonding strength between the aluminum alloy material (aluminum alloy layer 16b), the pure aluminum material (pure aluminum layer 16a), and the copper material (copper layer 17). As a result, the battery terminal component 1 constructed using the clad structure 1 can be expected to have long-term reliability even when used in batteries for automobiles, etc.

[0064] Here, the terminal connection structure on the negative electrode side of the battery will be described with an example of its configuration.

[0065] <Configuration example 1> As Configuration Example 1, FIG. 7 shows a terminal connection structure on the negative electrode side of a battery in which the clad structure 1 shown in FIG. 1 is used as a battery terminal component. In this Configuration Example 1, the battery terminal component 1 electrically connects the negative electrode side component 2 and the connection component 3. The negative electrode side component 2 shown in Configuration Example 1 is inserted into the second recess 15 of the clad structure 1 (battery terminal component 1). This insertion structure is preferably an interference fit, and more preferably, the negative electrode side component 2 and the leg portion 13 are joined by laser welding or the like. The negative electrode side component 2 is a conductive component electrically connected to the negative electrode in the battery and is an outlet port on the negative electrode side. The negative electrode side component 2 is generally made of a copper material.

[0066] On the other hand, the connection part 3 is joined to the upper flange surface 12A of the flange portion 12 of the clad structure 1 (battery terminal part 1) by laser welding, ultrasonic welding, or the like. The connection part 3 is a conductive part used outside the battery. The connection part 3 is a conductive part such as a bus bar for electrically connecting to other batteries, and can electrically connect multiple batteries to form an assembled battery. The connection part 3 is generally made of copper, nickel, pure aluminum, or aluminum alloy material, but in recent years, aluminum material has been preferred for its weight reduction and other reasons. Furthermore, aluminum alloy material is preferred for its strength in addition to its weight reduction.

[0067] When electrically connecting a negative electrode side component 2 made of copper and a connection component 3 made of aluminum (particularly aluminum alloy material) as in Configuration Example 1, it is preferable to use a clad structure 1 (battery terminal component 1) having one surface formed of a copper layer 17 made of substantially the same copper material as the negative electrode side component 2 and the other surface formed of an aluminum alloy layer 16b made of substantially the same aluminum alloy material as the connection component 3. This facilitates both the electrical connection between the negative electrode side component 2 and the copper layer 17 and the electrical connection between the connection component 3 and the aluminum alloy layer 16b, and also sufficiently enhances the bonding strength of both connections. In Configuration Example 1, a pure aluminum layer 16a is present between the aluminum alloy layer 16b and the copper layer 17. However, pure aluminum generally has better electrical conductivity than aluminum alloy materials. Therefore, the pure aluminum layer 16a does not impair the electrical conductivity of the clad structure 1 (battery terminal component 1).

[0068] <Configuration example 2> As Configuration Example 2, FIG. 8 shows a terminal connection structure on the negative electrode side of a battery using the clad structure 1 shown in FIG. 1 as a battery terminal component. The negative electrode side component 2 shown in Configuration Example 2 is plate-shaped with a through-hole, and the battery terminal component 1 is inserted into the through-hole. This insertion structure can be made into a loose fit or a clearance fit by providing a seal 4 between the negative electrode side component 2 and the flange 12 of the clad structure 1 (battery terminal component 1). Furthermore, Configuration Example 2 employs a crimping structure in which the leg portions 13 of the clad structure 1 (battery terminal component 1) are bent outward. This crimping structure stably fixes the negative electrode side component 2 by sandwiching it between the leg portions 13 and the flange 12. In this case, the negative electrode side component 2 and the leg portions 13 are preferably joined by laser welding or the like.

[0069] On the other hand, the connection part 3 is joined to the upper flange surface 12A of the flange portion 12 of the clad structure 1 (battery terminal part 1) by laser welding, ultrasonic welding, or the like. The connection part 3 is a conductive part used outside the battery. The connection part 3 is a conductive part such as a bus bar for electrically connecting to other batteries, and can electrically connect multiple batteries to form an assembled battery. The connection part 3 is generally made of copper, nickel, pure aluminum, or aluminum alloy material, but in recent years, aluminum material has been preferred for its weight reduction and other reasons. Furthermore, aluminum alloy material is preferred for its strength in addition to its weight reduction.

[0070] When electrically connecting a negative electrode side component 2 made of copper and a connection component 3 made of aluminum (particularly aluminum alloy material) as in Configuration Example 2, it is preferable to use a clad structure 1 (battery terminal component 1) having one surface formed of a copper layer 17 made of substantially the same copper material as the negative electrode side component 2 and the other surface formed of an aluminum alloy layer 16b made of substantially the same aluminum alloy material as the connection component 3. This facilitates both the electrical connection between the negative electrode side component 2 and the copper layer 17 and the electrical connection between the connection component 3 and the aluminum alloy layer 16b, and also sufficiently increases the bonding strength of both connections. Note that in Configuration Example 2, for the same reasons as in Configuration Example 1, the pure aluminum layer 16a does not impair the conductivity of the clad structure 1 (battery terminal component 1).

[0071] As described above, the battery terminal component 1 according to the present invention can electrically connect the negative electrode side component 2 and the connection component 3 even if the negative electrode side component 2 has a different shape or connection method, as in the above configuration examples 1 and 2. From this perspective, the battery terminal component 1 is expected to be put to practical use. [Explanation of symbols]

[0072] <Figures 1, 7, and 8> 1: Clad structure (battery terminal parts) 2: Negative electrode part 3: Connection parts 4: Sticker 10: Base, 10A: Upper base, 10B: Lower base 11: Wall, 11A: Inner wall surface (11Aa: Vertical wall surface, 11Ab: Slanted wall surface), 11B: External wall surface 12: flange portion, 12A: upper flange surface, 12B: lower flange surface, 12C: outer flange surface 13: Leg, 13A: Inner leg surface, 13B: Outer leg surface, 13C: Lower leg surface 14: First recess 15: Second recess 16: aluminum layer (Al layer), 16a: pure aluminum layer (pure Al layer), 16b: aluminum alloy layer (Al alloy layer) 17: Copper layer (Cu layer) <Figure 3> 100: Clad piece 116: aluminum layer (Al layer), 116a: pure aluminum layer (pure Al layer), 116b: aluminum alloy layer (Al alloy layer) 117: Copper layer (Cu layer) <Figure 4> 200: First molded body 210: Base, 210A: Upper base, 210B: Lower base 211: Wall, 211A: Inner wall surface (211Aa: Vertical wall surface, 211Ab: Slanted wall surface), 211B: External wall surface 212: flange portion, 212A: upper flange surface, 212B: lower flange surface, 212C: outer flange surface 214: First recess 216: aluminum layer (Al layer), 216a: pure aluminum layer (pure Al layer), 216b: aluminum alloy layer (Al alloy layer) 217: Copper layer (Cu layer) <Figure 5> 300: Second molded body 310: Base, 310A: Upper base, 310B: Lower base 311: Wall, 311A: Internal wall surface (311Aa: Vertical wall surface, 311Ab: Slanted wall surface), 311B: External wall surface 312: flange portion, 312A: upper flange surface, 312B: lower flange surface, 312C: outer flange surface 314: First recess 316: Aluminum layer (Al layer), 316a: Pure aluminum layer (Pure Al layer), 316b: Aluminum alloy layer (Al alloy layer) 317: Copper layer (Cu layer) <Figure 6> 400: Third molded body 410: Base, 410A: Upper base, 410B: Lower base 411: wall portion, 411A: inner wall surface (411Aa: vertical wall surface, 411Ab: inclined wall surface), 411B: outer wall surface 412: flange portion, 412A: upper flange surface, 412B: lower flange surface, 412C: outer flange surface 413: Leg, 413A: Internal leg surface, 413B: External leg surface, 413C: Lower leg surface 414: First recess 415: Second recess 416: aluminum layer (Al layer), 416a: pure aluminum layer (pure Al layer), 416b: aluminum alloy layer (Al alloy layer) 417: Copper layer (Cu layer)

Claims

1. a base having an upper surface and a lower surface; a wall portion having an inner wall surface and an outer wall surface extending upward from the outer edge of the upper bottom surface; a flange portion including upper and lower flange surfaces extending in a radial direction perpendicular to the wall portion from an end of the wall portion extending upward, and an outer flange surface at the end extending in the radial direction; a leg portion including an inner leg surface and an outer leg surface extending downward from the outer edge of the lower bottom surface, and a lower leg surface at an end extending downward; a first recess defined by the upper bottom surface and the inner wall surface; a second recess defined by the lower bottom surface and the inner leg surface, a first surface extending from the upper bottom surface, through the inner wall surface, to the upper flange surface is made of an aluminum alloy material; a second surface extending from the lower bottom surface through the inner leg surface, the lower leg surface, the outer leg surface, and the outer wall portion to the lower flange surface is made of a copper material; The clad structure has an aluminum material containing 99% by mass or more of Al present between the aluminum alloy material and the copper material.

2. The cladding structure according to claim 1 , wherein the inner wall surface of the wall portion is composed of a vertical wall surface extending upward from the upper bottom surface of the base portion and an inclined wall surface connecting from the vertical wall surface to the upper flange surface of the flange portion.

3. The cladding structure according to claim 1 or 2, wherein the outer flange surface of the flange portion has a boundary between the first surface continuing from the upper flange surface and the second surface continuing from the lower flange surface.

4. a base having an upper surface and a lower surface; a wall portion having an inner wall surface and an outer wall surface extending upward from the outer edge of the upper bottom surface; a flange portion including upper and lower flange surfaces extending in a radial direction perpendicular to the wall portion from an end of the wall portion extending upward, and an outer flange surface at the end extending in the radial direction; a leg portion including an inner leg surface and an outer leg surface extending downward from the outer edge of the lower bottom surface, and a lower leg surface at an end extending downward; a first recess defined by the upper bottom surface and the inner wall surface; a second recess defined by the lower bottom surface and the inner leg surface, a first surface extending from the upper bottom surface, through the inner wall surface, to the upper flange surface is made of an aluminum alloy material; a second surface extending from the lower bottom surface through the inner leg surface, the lower leg surface, the outer leg surface, and the outer wall portion to the lower flange surface is made of a copper material; The battery terminal component is configured using a clad structure in which an aluminum material containing 99% by mass or more of Al is present between the aluminum alloy material and the copper material.

5. 5. The battery terminal component according to claim 4, wherein the inner wall surface of the wall portion comprises a vertical wall surface extending upward from the upper bottom surface of the base portion and an inclined wall surface connecting from the vertical wall surface to the upper flange surface of the flange portion.

6. The battery terminal part according to claim 4 , wherein the outer flange surface of the flange portion has a boundary between the first surface continuing from the upper flange surface and the second surface continuing from the lower flange surface.

Images