Inter-device connection member

Abstract

To provide an inter-device connection member capable of suppressing the occurrence of corrosion between a first joint part of a first conductive member and a second joint part of a second conductive member, which are made of dissimilar metals.SOLUTION: The inter-device connection member 1 that connects the first electrode terminal 120 made of the first metal of one power storage device 100 and the second electrode terminal 130 made of the second metal of another power storage device 100 includes the first conductive member 10 made of the first metal and connected to the first electrode terminal 120, the second conductive member 20 made of the second metal and connected to the second electrode terminal 130, the joint portion 5 that joins the first joint portion 14 of the first conductive member 10 and the second joint portion 24 of the second conductive member 20, and the resin sealing member 30 that hermetically seals the joint portion 5.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an inter-device connection member that electrically connects a first electrode terminal made of a first metal of one energy storage device to a second electrode terminal made of a second metal different from the first metal of another energy storage device. [Background technology]

[0002] Inter-device connection members that electrically connect power storage devices such as batteries and capacitors are known. Specifically, there is an inter-device connection member that electrically connects a first electrode terminal (e.g., a positive electrode terminal) made of a first metal (e.g., aluminum) of one power storage device with a second electrode terminal (e.g., a negative electrode terminal) made of a second metal (e.g., copper) of the other power storage device. Furthermore, this inter-device connection member may be configured by joining a first conductive member made of the same first metal (e.g., aluminum) as the first electrode terminal with a second conductive member made of the same second metal (e.g., copper) as the second electrode terminal. For example, Patent Document 1 discloses a bus bar for a battery pack in which an aluminum plate and a copper plate are butted together to form a clad (see, for example, Figures 4 to 6 and paragraph (0026) of Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 155090 Summary of the Invention [Problem to be solved by the invention]

[0004] However, as mentioned above, when the first conductive member and the second conductive member that constitute the inter-device connection member are made of different metals, galvanic corrosion can occur between the first joint portion of the first conductive member and the second joint portion of the second conductive member where the two are joined.

[0005] The present invention has been made in consideration of the current situation, and provides an inter-device connection member that can suppress corrosion from occurring between the first joint portion of the first conductive member and the second joint portion of the second conductive member at the joint portion of the inter-device connection member that joins a first conductive member and a second conductive member made of different metals. [Means for solving the problem]

[0006] (1) One aspect of the present invention for solving the above problem is an inter-device connection member that connects a first electrode terminal made of a first metal of one power storage device to a second electrode terminal made of a second metal different from the first metal of another power storage device, the inter-device connection member comprising: a first conductive member made of the first metal and having a first connection portion that connects to the first electrode terminal; a second conductive member made of the second metal and having a second connection portion that connects to the second electrode terminal; a joint that joins the first joint portion of the first conductive member and the second joint portion of the second conductive member; and a resin sealing member that hermetically seals the joint portion.

[0007] In the above-described inter-device connection member, the joint between the first joint of the first conductive member and the second joint of the second conductive member, both made of different metals, is hermetically sealed with a resin sealing member, which prevents air and moisture from coming into contact with the joint and suppresses corrosion between the first and second joints.

[0008] Examples of the "electricity storage device" include secondary batteries such as lithium ion secondary batteries, sodium ion secondary batteries, and calcium ion secondary batteries, and capacitors such as lithium ion capacitors. Methods for joining the first joint of the first conductive member and the second joint of the second conductive member include welding such as laser welding and ultrasonic welding, fastening using bolts and nuts, FSW (friction stir welding), crimping such as TOX crimp (trademark), riveting, and joining using plastic deformation.

[0009] (2) The inter-device connecting member according to (1), further comprising: the first conductive member has a first seal portion between the first junction portion and the first connection portion; the first seal portion has a first roughened surface on which first nanopillars, each having a height of 50 nm or more, are formed by first particles derived from the first metal constituting the first conductive member and linked together in a string of beads around the entire periphery; the second conductive member has a second seal portion between the second junction portion and the second connection portion; and the second seal portion has a first roughened surface on which first nanopillars, each having a height of 50 nm or more, are formed by first particles derived from the first metal constituting the first conductive member and linked together in a string of beads around the entire periphery. The resin sealing member preferably has a second roughened surface on which stand second nanopillars of 50 nm or more in height, each second nanopillar being formed by linking together in a string of beads and originating from a metal, and the resin sealing member is formed by filling the spaces between the standing first nanopillars on the first roughened surface with a resin material constituting the resin sealing member and hermetically bonding them to the first sealing portion, and by filling the spaces between the standing second nanopillars on the second roughened surface with the resin material and hermetically bonding them to the second sealing portion, thereby covering the first bonding portion and the second bonding portion.

[0010] In the above-described inter-device connection member, a first roughened surface on the nano-level (nano-order) with the above-described first nanopillars standing tall is formed on the first sealing portion of the first conductive member, and a second roughened surface on the nano-level with the above-described second nanopillars standing tall is formed on the second sealing portion of the second conductive member. A resin material is then filled between the standing first nanopillars on the first roughened surface to hermetically bond a resin sealing member to the first sealing portion, and a resin material is filled between the standing second nanopillars on the second roughened surface to hermetically bond a resin sealing member to the second sealing portion, thereby entirely covering the first and second bonding portions, including the bonding portions. This allows the resin sealing member to entirely cover the first and second bonding portions, including the bonding portions, with particularly high airtightness, thereby more effectively suppressing corrosion between the first and second bonding portions.

[0011] (3) Furthermore, in the inter-device connection member described in (1) or (2), the first joint portion of the first conductive member and the second joint portion of the second conductive member may be integrally joined by plastic deformation of at least one of them.

[0012] For example, when a first joint of a first conductive member and a second joint of a second conductive member made of dissimilar metals are welded, a hard and brittle intermetallic compound may form at the weld, which could cause the weld to break when the inter-device connection member is subjected to vibration or impact. In contrast, the above-mentioned inter-device connection member does not use a welding method, but rather the first joint portion of the first conductive member and the second joint portion of the second conductive member are joined together by plastic deformation, thereby ensuring reliable joining of the first joint portion and the second joint portion.

[0013] (4) Further, in the inter-device connection member described in (3), the first joint portion of the first conductive member has a plate-shaped first plate-shaped portion, and the second joint portion of the second conductive member has a plate-shaped second plate-shaped portion, and the first plate-shaped portion and the second plate-shaped portion overlap in a plate thickness direction, and when the direction from the first plate-shaped portion toward the second plate-shaped portion in the plate thickness direction is defined as a first plate thickness direction and a second plate thickness direction is defined as a second plate thickness direction, the first plate-shaped portion It is preferable that the inter-device connection member includes a first crimped portion that protrudes in a cylindrical shape with a bottom in the first plate thickness direction, the second plate-shaped portion includes a second crimped portion that is in close contact with the first crimped portion and is recessed in a cylindrical shape with a bottom in the first plate thickness direction, the first crimped portion engages with the second crimped portion in the plate thickness direction, and has an outer diameter on the first plate thickness direction side that is larger than the outer diameter on the second plate thickness direction side, and is joined to the second crimped portion so as not to be removable from the second crimped portion in the second plate thickness direction.

[0014] In the above-described inter-device connection member, the first joint portion of the first conductive member has a first plate-shaped portion including a first tubular, bottomed crimped portion, and the second joint portion of the second conductive member has a second plate-shaped portion including a second tubular, bottomed crimped portion. The second crimped portion is in close contact with the outside of the first crimped portion, and the first crimped portion is joined to the second crimped portion so as not to be removable. Therefore, joining the first joint portion and the second joint portion does not require additional components such as rivets, thereby reducing the number of parts. Note that joining the first joint portion and the second joint portion may include only one pair of the first crimped portion and the second crimped portion, or multiple pairs. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is an explanatory diagram of a battery module configured using a bus bar according to an embodiment. [Figure 2] FIG. 2 is a top view of the bus bar according to the embodiment. [Figure 3] 3 is a cross-sectional view of the bus bar according to the embodiment taken along the arrow in FIG. 2. [Figure 4] 4 is an enlarged cross-sectional view of the bus bar according to the embodiment, in the vicinity of the resin sealing member in FIG. 3. [Figure 5] 4 is an explanatory view showing an enlarged view of a joint portion between a first roughened surface (or a second roughened surface) of a first conductive member (or a second conductive member) and a resin sealing member in a bus bar according to an embodiment. FIG. [Figure 6] 4 is a flowchart of a method for manufacturing a bus bar according to an embodiment. [Figure 7] 5A and 5B are explanatory views showing how a first conductive member and a second conductive member are crimped together using a punch and a die in the method for manufacturing the bus bar according to the embodiment. [Figure 8] FIG. 10 is an explanatory diagram showing a method for manufacturing a busbar according to an embodiment, in which a pulsed laser beam is scanned to form a plurality of first cup-shaped recesses and first nanopillars standing in each of the first cup-shaped recesses (or a plurality of second cup-shaped recesses and second nanopillars standing in each of the second cup-shaped recesses) in the first sealing portion of the first conductive member (or the second sealing portion of the second conductive member). DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. A bus bar (inter-device connection member) 1 (see FIGS. 1 to 4) of this embodiment is a member that electrically connects adjacent rectangular (rectangular) batteries 100 in a battery module 200 (see FIG. 1) that is mounted on vehicles such as hybrid cars, plug-in hybrid cars, and electric cars. The height direction AH, longitudinal direction BH, and lateral direction CH of the bus bar will be defined as the directions shown in FIGS. 1 to 4.

[0017] The battery module 200 includes a plurality of batteries 100 (see FIG. 1). The batteries 100 constituting the battery module 200 are housed in a module case (not shown) with their orientations alternately stacked in a row in the battery thickness direction, and are constrained in the battery stacking direction SH by the module case. The positive electrode terminal (first electrode terminal) 120 of one adjacent battery 100 and the negative electrode terminal (second electrode terminal) 130 of the other adjacent battery 100 are aligned in the battery stacking direction SH and are electrically connected (connected in series) via a bus bar 1. The bus bar 1 is joined to the positive electrode terminal 120 and the negative electrode terminal 130 by welding.

[0018] Each battery 100 is composed of a case 110, an electrode assembly (not shown) including positive and negative electrode plates and an electrolyte (not shown) housed in the case 110, a positive terminal 120 and a negative terminal 130 each supported by the case 110, and the like. The case 110 is made of metal (aluminum in this embodiment) and has a rectangular box shape. A top wall 111 of the case 110 is provided with a safety valve 113 that ruptures and opens when the internal pressure of the case 110 exceeds a valve opening pressure. A liquid inlet (not shown) is also provided in the top wall 111 of the case 110, and this liquid inlet is airtightly sealed with a disk-shaped sealing member 115 made of aluminum.

[0019] A positive electrode terminal 120 and a negative electrode terminal 130 are fixed to the upper wall portion 111 of the case 110. Specifically, a pair of insertion holes (not shown) are provided in the upper wall portion 111 of the case 110, and the positive electrode terminal 120 made of a first metal (aluminum in this embodiment) is inserted into one of the insertion holes, and the negative electrode terminal 130 made of a second metal (copper in this embodiment) different from the first metal is inserted into the other insertion hole. The positive electrode terminal 120 is fixed to the upper wall portion 111 of the case 110 via an insert-molded insulating member 125, and the negative electrode terminal 130 is fixed to the upper wall portion 111 of the case 110 via an insert-molded insulating member 135.

[0020] Of the positive terminal 120, a rectangular plate-shaped positive electrode top plate portion 121 is disposed on the outside of the case 110, and a bus bar 1 is welded to this positive electrode top plate portion 121. This positive terminal 120 is conductively connected to a positive electrode current collector of the electrode body within the case 110. Furthermore, of the negative terminal 130, a rectangular plate-shaped negative electrode top plate portion 131 is disposed on the outside of the case 110, and a bus bar 1 is welded to this negative electrode top plate portion 131. This negative terminal 130 is conductively connected to a negative electrode current collector of the electrode body within the case 110.

[0021] Next, the busbar 1 will be described (see FIGS. 1 to 5). The busbar 1 is composed of a first conductive member 10 made of the same first metal (aluminum in this embodiment) as the positive terminal 120, a second conductive member 20 made of the same second metal (copper in this embodiment) as the negative terminal 130, and a resin sealing member 30 that hermetically seals a joint 5 at which the first conductive member 10 and the second conductive member 20 are joined.

[0022] The first conductive member 10 is formed by bending an aluminum plate in its thickness direction and has a crank shape (Z-shape) including a first connecting portion 11, a first rising portion 12, and a first extending portion 13. The first connecting portion 11 is a rectangular plate extending in the longitudinal direction BH and the lateral direction CH. This first connecting portion 11 is a portion to be welded to a positive electrode top plate portion 121 of a positive terminal 120 of the battery 100. The first rising portion 12 is a rectangular plate extending in the height direction AH and the lateral direction CH, bent from an end portion on the other side BH2 of the first connecting portion 11 in the longitudinal direction BH, and rising to an upper side AH1 in the height direction AH. The first extending portion 13 is a rectangular plate extending in the longitudinal direction BH and the lateral direction CH, bent from an upper end portion of the first rising portion 12, and extending parallel to the first connecting portion 11 to the other side BH2 in the longitudinal direction BH. The first extending portion 13 has a first joint portion 14 joined to the second conductive member 20, and a first sealing portion 16 located closer to the first connecting portion 11 than the first joint portion 14. The first joint portion 14 will be described in detail later.

[0023] The first sealing portion 16 has a ring-shaped first roughened surface 16m (see FIG. 4) that extends along the entire circumference perpendicular to the longitudinal direction BH. This first roughened surface 16m is a nano-level roughened surface, and as shown in FIG. 5, it is covered with a forest of nano-level first nanopillars 17, each of which has a height ha of 50 nm or more and less than 1000 nm and is made up of first particles 17p derived from the metal that forms the first conductive member 10 and linked together in a string-like pattern. In this embodiment, the height ha of each first nanopillar 17 is approximately 200 nm. As described above, the metal that forms the first conductive member 10 is aluminum, and the first nanopillars 17 are made up of first particles 17p made of aluminum and aluminum oxide.

[0024] The second conductive member 20 is formed by bending a copper plate in its thickness direction. It has a shape similar to that of the first conductive member 10, and is crank-shaped (Z-shaped) with a second connecting portion 21, a second rising portion 22, and a second extending portion 23. The second connecting portion 21 is a rectangular plate extending in the longitudinal direction BH and the lateral direction CH, and is welded to a negative electrode top plate portion 131 of a negative electrode terminal 130 of the battery 100. The second rising portion 22 is a rectangular plate extending in the height direction AH and the lateral direction CH, and is bent from an end portion on one side BH1 of the second connecting portion 21 in the longitudinal direction BH to rise to an upper side AH1. The second extending portion 23 is a rectangular plate extending in the longitudinal direction BH and the lateral direction CH, and is bent from an upper end portion of the second rising portion 22 to extend parallel to the second connecting portion 21 toward one side BH1 in the longitudinal direction BH. The second extending portion 23 has a second joint portion 24 joined to the first joint portion 14 of the first conductive member 10, and a second sealing portion 26 located closer to the second connecting portion 21 than the second joint portion 24. The second joint portion 24 will be described in detail later.

[0025] The second sealing portion 26 has a ring-shaped second roughened surface 26m (see FIG. 4) extending along the entire circumference perpendicular to the longitudinal direction BH. This second roughened surface 26m is also a nano-level roughened surface, and as shown in FIG. 5, second particles 27p derived from the metal constituting the second conductive member 20 are linked together in a string-like pattern to form columnar shapes, forming nano-level second nanopillars 27. Each second nanopillar 27 has a height ha of 50 nm or more and less than 1000 nm. In this embodiment, the height ha of each second nanopillar 27 is approximately 200 nm. As described above, the metal constituting the second conductive member 20 is copper, and the second nanopillars 27 are made of second particles 27p made of copper and copper oxide.

[0026] The first joint portion 14 of the first conductive member 10 and the second joint portion 24 of the second conductive member 20 are joined together by plastic deformation of these first joint portion 14 and second joint portion 24. The aforementioned joint portion 5 is the portion where the first joint portion 14 and the second joint portion 24 are in close contact with each other. Specifically, the first joint portion 14 is entirely a plate-shaped first plate-shaped portion 14p, and the second joint portion 24 is entirely a plate-shaped second plate-shaped portion 24p, with the first plate-shaped portion 14p and the second plate-shaped portion 24p overlapping in the plate-thickness direction TH. Within the plate-thickness direction TH, the direction from the first plate-shaped portion 14p to the second plate-shaped portion 24p is referred to as a first plate-thickness direction TH1, and the direction from the second plate-shaped portion 24p to the first plate-shaped portion 14p is referred to as a second plate-thickness direction TH2. In this embodiment, the first plate-thickness direction TH1 coincides with a lower side AH2 in the height direction AH of the busbar 1, and the second plate-thickness direction TH2 coincides with an upper side AH1 in the height direction AH of the busbar 1.

[0027] The first joint portion 14 (first plate-shaped portion 14p) has a first crimped portion 14d that protrudes in a cylindrical shape with a bottom in the first plate-thickness direction TH1. The second joint portion 24 (second plate-shaped portion 24p) is in close contact with the first crimped portion 14d from the outside and has a second crimped portion 24d that is recessed in a cylindrical shape with a bottom in the first plate-thickness direction TH1. Specifically, the first crimped portion 14d has an outer diameter φ1 on its tip side (first plate-thickness direction TH1 side) that is larger than an outer diameter φ2 on its base end side (second plate-thickness direction TH2 side). The second crimped portion 24d that is in close contact with the first crimped portion 14d has an inner diameter (the same as the outer diameter φ1) on its tip side (first plate-thickness direction TH1 side) that is larger than an inner diameter (the same as the outer diameter φ2) on its base end side (second plate-thickness direction TH2 side). As a result, the first crimping portion 14d and the second crimping portion 24d are engaged in the plate thickness direction TH, and the first crimping portion 14d is joined to the second crimping portion 24d so as not to be removed from the second crimping portion 24d in the second plate thickness direction TH2.

[0028] Next, the resin sealing member 30 will be described. The resin sealing member 30 has a rectangular parallelepiped outer shape and airtightly covers a portion of the first extending portion 13 of the first conductive member 10 (a portion including the entire first joint portion 14) and a portion of the second joint portion 24 of the second conductive member 20 (a portion including the entire second joint portion 24). This airtightly seals the joint portion 5 between the first conductive member 10 and the second conductive member 20. The resin sealing member 30 is made of a resin material 31 containing a thermoplastic resin, a thermoplastic elastomer, and a fibrous filler. In this embodiment, the thermoplastic resin is polyphenylene sulfide (PPS), the thermoplastic elastomer is a thermoplastic polyurethane elastomer, and the fibrous filler is glass fiber. The resin sealing member 30 is insert-molded as described below.

[0029] The resin sealing member 30 is airtightly joined to the annular first roughened surface 16m of the first seal portion 16 of the first extending portion 13 of the first conductive member 10. In detail, a resin material 31 constituting the resin sealing member 30 is filled between the first nanopillars 17 standing tall on the first roughened surface 16m, and the resin sealing member 30 is airtightly joined to the first seal portion 16. This effectively prevents air and moisture from entering the resin sealing member 30 from the boundary between the first conductive member 10 and the resin sealing member 30 and coming into contact with the joint portion 5. Furthermore, the resin sealing member 30 is airtightly joined to the annular second roughened surface 26m of the second seal portion 26 of the second extending portion 23 of the second conductive member 20. In detail, the resin material 31 constituting the resin sealing member 30 is filled between the second nanopillars 27 standing tall on the second roughened surface 26m, and the resin sealing member 30 is airtightly joined to the second seal portion 26. This effectively prevents air and moisture from entering the interior of the resin sealing member 30 from the boundary between the second conductive member 20 and the resin sealing member 30 and coming into contact with the joint portion 5.

[0030] In the busbar 1 of this embodiment, the joint 5, which joins the first joint 14 of the first conductive member 10 and the second joint 24 of the second conductive member 20, both made of different metals, is airtightly sealed with a resin sealing member 30. This prevents air and moisture from coming into contact with the joint 5, and inhibits corrosion from occurring between the first joint 14 and the second joint 24.

[0031] Furthermore, in this embodiment, a nano-level first roughened surface 16m with a forest of first nanopillars 17 is formed on the first seal portion 16 of the first conductive member 10, and a nano-level second roughened surface 26m with a forest of second nanopillars 27 is formed on the second seal portion 26 of the second conductive member 20. A resin material 31 is then filled between the forest of first nanopillars 17 on the first roughened surface 16m to airtightly bond the resin sealing member 30 to the first seal portion 16, and a resin material 31 is filled between the forest of second nanopillars 27 on the second roughened surface 26m to airtightly bond the resin sealing member 30 to the second seal portion 26, thereby covering the entire first bonding portion 14 and the second bonding portion 24, including the bonding portion 5. By doing so, the entire first bonding portion 14 and the second bonding portion 24, including the bonding portion 5, can be covered with the resin sealing member 30 with particularly high airtightness, thereby more effectively suppressing corrosion from occurring between the first bonding portion 14 and the second bonding portion 24.

[0032] Furthermore, in this embodiment, the first joint 14 of the first conductive member 10 and the second joint 24 of the second conductive member 20 are joined together by plastic deformation without using a welding technique, so that the first joint 14 and the second joint 24 can be reliably joined. In this embodiment, the first joint portion 14 of the first conductive member 10 has a first plate-shaped portion 14p including a first tubular crimped portion 14d with a bottom, and the second joint portion 24 of the second conductive member 20 has a second plate-shaped portion 24p including a tubular second crimped portion 24d with a bottom, with the second crimped portion 24d closely contacting the outside of the first crimped portion 14d and the first crimped portion 14d being joined to the second crimped portion 24d so as not to be removable from the second crimped portion 24d. Therefore, no other members such as rivets are required to join the first joint portion 14 and the second joint portion 24, reducing the number of parts.

[0033] Next, a method for manufacturing the busbar 1 will be described (see FIGS. 6 to 8). First, in a first conductive member forming step S1 (see FIG. 6), the first conductive member 10 is formed. Specifically, an aluminum plate is cut into a rectangular shape of a predetermined size. Thereafter, this plate is bent in the thickness direction to form the crank-shaped first conductive member 10 (see FIGS. 2 to 4) having the first connection portion 11, the first rising portion 12, and the first extending portion 13. Separately, in the second conductive member forming step S2, the second conductive member 20 is formed. Specifically, a copper plate is cut into a rectangular shape of a predetermined size. Then, this plate is bent in the thickness direction to form the crank-shaped second conductive member 20 (see FIGS. 2 to 4) having the second connection portion 21, the second rising portion 22, and the second extending portion 23.

[0034] Next, in the crimping step S3 (see FIG. 6), the first extending portion 13 of the first conductive member 10 and the second extending portion 23 of the second conductive member 20 are crimped together. This crimping step S3 is performed using a die DE having a recess Dh that is circular in plan view, and a punch PT having a cylindrical tip portion Ps whose outer diameter is smaller than the inner diameter of the recess Dh of the die DE (see FIG. 7).

[0035] First, the unmachined first extending portion 13 of the first conductive member 10 and the unmachined second extending portion 23 of the second conductive member 20 are placed between the tip Ps of the punch PT and the recess Dh of the die DE, and these are overlapped in the plate thickness direction TH. The first extending portion 13 of the first conductive member 10 is placed on the punch PT side, and the second extending portion 23 of the second conductive member 20 is placed on the die DE side. Then, the tip Ps of the punch PT is moved toward the recess Dh of the die DE, and the tip Ps of the punch PT and the recess Dh of the die DE recess part of the first extending portion 13 and part of the second extending portion 23 in the first plate thickness direction TH1 of the plate thickness direction TH, thereby integrally forming them. As a result, a first plate-shaped portion 14p (first joint portion 14) having the aforementioned first crimping portion 14d is formed in the first extension portion 13, and a second plate-shaped portion 24p (second joint portion 24) having the aforementioned second crimping portion 24d is formed in the second extension portion 23, thereby electrically connecting the first conductive member 10 and the second conductive member 20.

[0036] Next, in the nano-roughening process S4 (see Figure 6), the first conductive member 10 and the second conductive member 20 joined in the crimping joining process S3 are subjected to a surface roughening treatment to form a nano-level first roughened surface 16m on the first seal portion 16 of the first conductive member 10 and a nano-level second roughened surface 26m on the second seal portion 26 of the second conductive member 20.

[0037] Specifically, pulsed laser light LB is intermittently irradiated onto the first sealing portion 16 of the first conductive member 10 while shifting the irradiation position, forming a first roughened surface 16m in which a large number of first bowl-shaped recesses 18 each containing a forest of first nanopillars 17 are arranged in a partially overlapping manner (see FIG. 8). The laser irradiation conditions were a wavelength of 1064 nm, a peak output of 5 kW, a pulse width of 150 ns, a pitch pb of 75 μm, and a spot diameter of 80 μm. In the portion of the first sealing portion 16 irradiated with the pulsed laser beam LB, the first metal (aluminum in this embodiment) near the surface melts and turns into vapor. Thereafter, as the temperature of the vapor drops, it turns into first particles 17p of aluminum and aluminum oxide and accumulates in the first bowl-shaped recess 18. By intermittently irradiating the surface with the pulsed laser beam LB while shifting the irradiation position, the first particles 17p accumulate in a string of beads and combine to form columns, forming a forest of first nanopillars 17.

[0038] The second sealing portion 26 of the second conductive member 20 is also irradiated intermittently with pulsed laser light LB while shifting the irradiation position, to form a second roughened surface 26m in which a large number of second bowl-shaped recesses 28 each containing a forest of second nanopillars 27 are arranged in a partially overlapping manner. The laser irradiation conditions were a wavelength of 1064 nm, a peak output of 20 kW, a pulse width of 50 ns, a pitch pb of 60 μm, and a spot diameter of 75 μm. In the portion of the second sealing portion 26 irradiated with the pulsed laser beam LB, the second metal (copper in this embodiment) near the surface melts and turns into vapor. Thereafter, as the temperature of the vapor drops, it turns into second particles 27p of copper and copper oxide and accumulates in the second bowl-shaped recess 28. By intermittently irradiating the portion with the pulsed laser beam LB while shifting the irradiation position, the second particles 27p accumulate in a string of beads and combine to form columns, forming a forest of second nanopillars 27.

[0039] Next, in the resin molding step S5 (see FIG. 6), the resin sealing member 30 is molded. Specifically, using a molding die (not shown) having upper and lower dies, the first conductive member 10 and the second conductive member 20 after the nano-roughening step S4 are placed at predetermined positions in the lower die, and then the upper die is moved toward the lower die to close the molding die. Next, molten resin of the resin material 31 is injected into the cavity to fill the cavity with the molten resin. At this time, the molten resin of the resin material 31 also fills the spaces between the first nanopillars 17 standing on the first roughened surface 16m of the first seal portion 16 of the first conductive member 10 and the spaces between the second nanopillars 27 standing on the second roughened surface 26m of the second seal portion 26 of the second conductive member 20 (see FIG. 5). Then, a resin sealing member 30 is molded to hermetically bond to the first seal portion 16 of the first conductive member 10 and the second seal portion 26 of the second conductive member 20, and to hermetically cover the first joint portion 14 of the first conductive member 10 and the second joint portion 24 of the second conductive member 20. In this way, the busbar 1 is completed.

[0040] Although the present invention has been described above in accordance with the embodiments, it goes without saying that the present invention is not limited to the embodiments and can be modified and applied as appropriate within the scope of the invention. [Explanation of symbols]

[0041] 1 Bus bar (connecting member between devices) 5 Joint 10 First conductive member 11 First connection part 14 1st joint 14p First plate-shaped part 14d First crimping part 16 First seal part 16m 1st roughened surface 17 First nano pillar 17p (the first particle that constitutes the first nanopillar) 20 Second conductive member 21 Second connection part 24 Second joint 24p Second plate-shaped part 24d Second crimping part 26 Second seal part 26m 2nd roughened surface 27 Second nano pillar 27p (the second particle that constitutes the second nanopillar) 30 Resin sealing material 31 Resin material 100 Batteries (energy storage devices) 120 positive electrode terminal (first electrode terminal) 130 Negative electrode terminal (second electrode terminal) TH Thickness direction TH1 1st plate thickness direction TH2 2nd plate thickness direction

Claims

1. An inter-device connection member that connects a first electrode terminal made of a first metal of one power storage device and a second electrode terminal made of a second metal different from the first metal of another power storage device, The first metal is a first connection portion that connects to the first electrode terminal; a first conductive member; The second metal is A second connection portion that connects to the second electrode terminal A second conductive member; a joint portion at which a first joint portion of the first conductive member and a second joint portion of the second conductive member are joined together; a resin sealing member that hermetically seals the joint portion. Inter-device connection components.

2. The device-to-device connection member according to claim 1 , the first conductive member has a first seal portion between the first joint portion and the first connection portion, the first sealing portion has a first roughened surface around its entire periphery, on which stand a forest of first nanopillars each having a height of 50 nm or more, each first nanopillar being formed by first particles derived from the first metal constituting the first conductive member and linked together in a string-like pattern; the second conductive member has a second seal portion between the second joint portion and the second connection portion, the second sealing portion has a second roughened surface around its entire periphery, the second roughened surface being covered with second nanopillars each having a height of 50 nm or more, the second nanopillars being formed by linking together second particles derived from the second metal constituting the second conductive member in a string-like pattern, The resin sealing member is A resin material constituting the resin sealing member is filled between the first nanopillars standing in the first roughened surface, and the resin material is airtightly bonded to the first seal portion, and the resin material is filled between the second nanopillars standing in the second roughened surface, and the second nanopillars are airtightly joined to the second seal portion; covering the first bonding portion and the second bonding portion Inter-device connection components.

3. 3. The device-to-device connecting member according to claim 1, The first joint portion of the first conductive member and the second joint portion of the second conductive member are integrally joined by plastic deformation of at least one of them. Inter-device connection components.

4. The device-to-device connecting member according to claim 3, the first joint portion of the first conductive member has a first plate-shaped portion, the second joint portion of the second conductive member has a second plate-shaped portion, The first plate-shaped portion and the second plate-shaped portion overlap each other in a plate thickness direction, In the plate thickness direction, a direction from the first plate-shaped portion toward the second plate-shaped portion is defined as a first plate thickness direction; When the direction from the second plate-shaped portion toward the first plate-shaped portion is defined as a second plate thickness direction, the first plate-shaped portion includes a first crimping portion that protrudes in the first plate thickness direction into a cylindrical shape with a bottom, the second plate-shaped portion includes a second crimping portion that is in close contact with the first crimping portion and is recessed in a cylindrical shape with a bottom in the first plate thickness direction, The first crimping portion is the second crimped portion is engaged with the second crimped portion in the plate thickness direction and joined to the second crimped portion so as not to be removed from the second crimped portion in the second plate thickness direction; Inter-device connection components.

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