JP6525230B2 - Bonding structure and bonding method, metal lead - Google Patents

Description

  The present invention relates to the technical field of joining materials to be welded by welding.

  It is known that a solar cell panel is formed by connecting a plurality of solar cells in series and in parallel. This solar battery cell has an N electrode on one side and a P electrode on the other side.

  When forming a solar cell panel, when connecting a solar cell in series, in a solar cell panel, N electrode of the solar cell which is one connection object, and N electrode of the solar cell which is the other connection object And are connected using an interconnector. Here, the interconnector is a current collecting wiring formed of a metallic thin plate. The parallel gap resistance welding (hereinafter, also simply referred to as "parallel gap welding") shown in FIG. 13 is used in a method of manufacturing a solar cell panel in which a plurality of solar cells are connected to each other by using this interconnector. .

  FIG. 13 is a diagram illustrating an example of joining the solar battery cell 202 and the interconnector 203 using generally known parallel gap resistance welding.

  As shown in FIG. 13, in parallel gap resistance welding, parallel gap electrodes 201 (201 a, 201 b) spaced apart by a gap are brought into contact with the interconnector 203 and press the interconnector 203. Further, in parallel gap resistance welding, current is supplied from the one parallel gap electrode 201 a to the other parallel gap electrode 201 b through the interconnector 203. Thereby, parallel gap resistance welding can join the solar cell 202 and the interconnector 203 by melting.

  Parallel gap resistance welding not only requires a large amount of welding energy but also causes a problem that the solar battery cell is warped when welding the welding area required to obtain a desired welding strength at one time . In order to solve this problem, in parallel gap resistance welding, while dividing the welding point required to obtain a desired welding strength into several points, continuous multipoint welding which welds the divided welding points (hereinafter referred to as It is simply called "multi-point welding". This multi-point welding can not only obtain desired welding strength, but also can provide redundancy of the welding point.

  However, in such multipoint welding, there is a problem that when the material to be welded is locally heated, welding distortion occurs due to heat contraction in the weld portion and the periphery thereof. That is, in the case of continuous multipoint welding, welding strains generated in the process of multipoint welding are accumulated. Therefore, at the welding end point in multipoint welding, in particular, deterioration of the welding quality is concerned.

  From such background, Patent Document 1 and Patent Document 2 disclose methods for avoiding the accumulation of the welding distortion. Patent Document 1 discloses a technology related to a method of electrically connecting solar cells. In the electrical connection method disclosed in Patent Document 1, when connecting the interconnectors to the N electrode and the P electrode of the solar cell at multiple points, the connection points are not arranged in a straight line but are arranged in a staggered manner and in a staggered manner. Weld the specified connection points. Thus, the electrical connection method can reduce the accumulation of welding distortion due to multipoint welding.

  Patent Document 2 discloses techniques relating to an electrode structure and a method of manufacturing the same, and an electrically heated catalyst and a method of manufacturing the same. Such an electrode structure has a conductive layer provided on a ceramic substrate and a comb-shaped electrode fixed to the conductive layer. In addition, the conductive layer has fine unevenness on the surface in contact with the electrode. The electrode structure is melted by energization heating of the comb-like electrode. Thus, the melted comb-like electrode enters the concavo-convex recess formed in the conductive layer and solidifies to form an anchor portion. That is, the said electrode structure can couple | bond an electrode and a conductive layer by the anchor effect of the formed anchor part. In addition, the electrode structure can reduce and alleviate the thermal stress generated between the ceramic base and the electrode. Thereby, the said electrode structure can suppress peeling of the electrode with respect to a ceramic base material.

  As related techniques existing prior to the present application, there are, for example, the following patent documents.

  That is, Patent Document 3 discloses a technique related to a method of manufacturing a projection welding method and a window regulator. In the projection welding method disclosed in Patent Document 3, any one of the first welding member and the second welding member is provided with a projection that abuts on the other welding member. According to the welding method, the first welding member and the second welding member are superposed and the welding members are welded using two welding electrodes. Thereby, the welding method which concerns is joined the 1st welding member from which plate | board thickness differs, and a 2nd welding member by enlarging the electrical resistance value of any one welding electrode among two welding electrodes. be able to.

  Patent document 4 discloses the technique regarding the joining method and joining structure of a dissimilar metal. More specifically, in the joining method of dissimilar metals, when overlapping and joining materials made of dissimilar metals, a protrusion is formed in one material to be joined, and a seal material is disposed around the formed protrusion. Furthermore, the joining method of the said dissimilar metal joins in the state which overlap | superposed the material which arrange | positioned the sealing material, and the other material so that the sealing material might be pinched | interposed. Thereby, the joining method of the dissimilar metal can prevent corrosion due to contact of the dissimilar metal.

  Patent Document 5 discloses a technique related to a sandwich panel and a method for manufacturing a vehicle body component. More specifically, according to the manufacturing method disclosed in Patent Document 5, an intermediate layer in which a pot-shaped recess is formed in a metal sheet such as aluminum or aluminum alloy, and a metal thin plate such as aluminum or aluminum alloy The cover layer is adhered to both sides of the intermediate layer by a polyurethane adhesive. This allows, for example, the manufacturer to produce sandwich panels at low cost.

Japanese Patent Application Laid-Open No. 62-042468 JP 2012-149311 A JP 2002-361440 A JP, 2008-000754, A Japanese Patent Publication No. 2003-508270

  Patent Document 1 and Patent Document 2 described above can be expected to have an effect of reducing the welding distortion. However, the techniques disclosed in Patent Document 1 and Patent Document 2 are, for example, in a state in which the welding start point is restrained by being welded (hereinafter referred to as “restrained state” in the present application) When newly welding another different welding point, a welding defect may occur due to the variation of the welding state (hereinafter also referred to as “fixed state”) at the start point.

  Furthermore, for example, in Patent Document 1, in order to avoid the influence of variations in the welding state, in the electrical connection method, the welding start point and the other welding points are vertically or horizontally with respect to the starting point. It is necessary to keep enough space between Therefore, in the electrical connection method, for example, it is necessary to increase a large area (hereinafter, referred to as “welding area” in the present application) in which a plurality of welding points can be provided in the interconnector. That is, in such an electrical connection method, the welding area may be expanded.

  As a technique for reducing the welding area, a method is known in which a plurality of welding points are overlapped at one place and welded. However, in the method of superposing and welding, there is a problem that stable welding can not be performed because energy required for joining is accumulated in one place.

  Further, for example, in the electrode structure disclosed in Patent Document 2, since the comb-shaped electrode is thin and thin, there is a possibility that the tip of the electrode may be deformed when transporting, storing, and welding the electrode. Therefore, in such an electrode structure, the minute welding electrode can not accurately press the electrode. Moreover, in the said electrode structure, when welding the deformed electrode front-end | tip, the dispersion | variation in a restraint state generate | occur | produces. That is, in the electrode structure which concerns, a variation arises in welding quality.

  Patent documents 3 to 5 only describe welding different welding methods of different metals and welding members having different thicknesses, and decrease the welding quality and increase the welding area due to the dispersion of the restraint state. No consideration is given to welding without any mention.

  The main object of the present invention is to provide a joint structure and the like capable of welding with less welding energy without expanding the welding area and without being influenced by the variation in the restraint state of the welding point already welded. To aim.

  In order to achieve the above-mentioned subject, the junction structure concerning the present invention is characterized by having the following composition.

That is, the joint structure according to the present invention is
One or more welding points for electrically connecting a material to be welded and another material to be welded different from the material to be welded;
At least one surface of the material to be welded is provided with a recess provided so as to surround the vicinity of the vicinity of the welding point;
It is characterized by having.

  Alternatively, the object is also achieved by a metal lead having the joint structure shown above.

  Further, in order to achieve the same object, a bonding method according to the present invention is characterized by comprising the following configuration.

That is, the bonding method of the bonding portion according to the present invention is
Providing one or more welding points electrically connecting the material to be welded and another material to be welded different from the material to be welded;
A recess is provided on at least one surface of the material to be welded so as to surround the vicinity of the welding point,
The material to be welded having the one or more welding points and the recess and the other material to be welded are joined at one or more welding points using parallel gap resistance welding.

  According to the present invention, it is possible to provide a joint structure and the like capable of welding with less welding energy without expanding the welding area and without being influenced by the variation in the restraint state of the welding point already welded. Can.

It is a figure which illustrates the aspect by which the interconnector which has the 1st joining structure in the 1st Embodiment of this invention, and a photovoltaic cell were connected. It is a top view which shows the principal part of the interconnector which has a 1st joining structure in the 1st Embodiment of this invention. It is sectional drawing which shows the interconnector which has a 1st joining structure in the 1st Embodiment of this invention. It is sectional drawing which shows the interconnector which has a 2nd joining structure in the 1st Embodiment of this invention. The aspect which welds the interconnector which has the 1st joining structure in the 1st Embodiment of this invention, and a photovoltaic cell using the parallel gap welding apparatus which has the parallel gap electrode by which the front-end was formed thinly is shown. It is sectional drawing which shows the interconnector which has the 3rd joining structure in the 1st Embodiment of this invention. It is a top view which shows the principal part of the interconnector which has a 4th joining structure in the 1st Embodiment of this invention. It is a figure which illustrates the aspect by which the interconnector which has the 1st junction structure in the 2nd Embodiment of this invention, and several solar cells were connected. It is sectional drawing which shows the interconnector which has a 1st joining structure in the 2nd Embodiment of this invention. It is sectional drawing which shows the interconnector which has a 1st joining structure in the 2nd Embodiment of this invention. It is sectional drawing which shows the interconnector which has a 5th joining structure in the 3rd Embodiment of this invention. It is a figure which illustrates the aspect which joins the interconnector which has the 1st joining structure in the 1st Embodiment of this invention, and a photovoltaic cell using parallel gap resistance welding. It is a figure which illustrates the aspect which welds a photovoltaic cell and an interconnector using a generally known parallel gap resistance welding.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, for convenience of explanation, one or more solar battery cells (that is, materials to be welded different from interconnectors), interconnectors (materials to be welded), etc. constituting a generally known solar battery panel The case where the present invention is applied to the interconnector (metal lead) in electrically connecting the metal lead to the metal lead will be described.

  For convenience of explanation, the description will be made using three-dimensional (X, Y, Z) coordinate axes described in each drawing.

First Embodiment
An interconnector 1 having a first joint structure according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 9 and 12. FIG. 1: is a figure which illustrates the aspect by which the interconnector 1 which has the 1st joining structure in the 1st Embodiment of this invention, and the photovoltaic cell 2 were connected.

  In FIG. 1, the interconnector 1 has one or more welding points 3 (3 a, 3 b, 3 c, 3 d, 3 e) for electrically connecting the interconnector 1 and a recess 4. The solar battery cell 2 has, for example, an N electrode 5 for convenience of explanation.

  In the present invention described by taking this embodiment as an example, for convenience of explanation, a configuration having five welding points 3 (3a, 3b, 3c, 3d, 3e) will be described as an example, but the present invention is not limited to the configuration described above. (Hereinafter, the same applies to each embodiment).

  FIG. 12 is a diagram illustrating an aspect of joining the interconnector 1 having the first joining structure and the solar battery cell 2 according to the first embodiment of the present invention using parallel gap resistance welding.

  In FIG. 12, the parallel gap welding apparatus 204 has a parallel gap electrode 201a and a parallel gap electrode 201b. The interconnector 1 and the N electrode 5 of the solar battery cell 2 are welded by the parallel gap welding apparatus 204 shown in FIG. 12 from the + Z direction (front side in the drawing) to the −Z direction (back side in the drawing) of the interconnector 1 The parallel gap electrodes 201 (201a and 201b) are pressure-welded to the point 3 and are joined by energization.

  FIG. 2 is a top view showing the main part of the interconnector 1 having the first bonding structure in the first embodiment of the present invention.

  The interconnector 1 has a welding point 3 and a recess 4 provided in a concave shape so as to surround the vicinity of the welding point 3 on at least one surface of the interconnector 1 (material to be welded). That is, the interconnector 1 has the welding point 3 and the recess 4 provided in the vicinity of the welding point 3 so as to surround the periphery of the welding point 3.

  FIG. 3 is a cross-sectional view (AA cross-sectional view in FIG. 2) showing the interconnector 1 having the first bonding structure in the first embodiment of the present invention.

  In FIG. 3, for convenience of explanation, the recess 4 has a welding surface 6 including a welding point 3 in the −Z direction (downward in the drawing). Further, welding surface 6 has an upper surface in the + Z direction (the upper direction in the drawing) and a bottom surface (lower surface) in the −Z direction. Furthermore, the recess 4 has a side surface 7 at the end of the welding surface 6. That is, the recessed part 4 has the side surface 7 (7a, 7b) standingly arranged in +/- (plus-minus) X direction (paper surface left-right direction).

  More specifically, for example, when welding the interconnector 1 and the solar battery cell 2 to the bottom surface of the welding surface 6 shown in FIG. 3, welding of the solar battery cell 2 (material to be welded) to be joined A surface formed horizontally or substantially horizontally with a point (not shown) can be employed.

  In the embodiment described above, for convenience of explanation, the bottom surface of the welding surface 6 is, as an example, a surface formed horizontally or substantially horizontally with the welding point of the solar battery cell 2 (material to be welded) to be joined The structure which employ | adopted was demonstrated to the example. However, the embodiment according to the present invention is not limited to such a configuration.

  FIG. 4 is a cross-sectional view (AA cross-sectional view in FIG. 2) showing the interconnector 1 having the second bonding structure in the first embodiment of the present invention. For example, as shown in FIG. 4, a bottom surface of the welding surface 6 may be a surface formed to be curved in the −Z direction. That is, the bottom surface of the welding surface 6 can adopt a surface having a curvature. In that case, the curvature which concerns may just employ | adopt the magnitude | size which can obtain desired welding strength, for example.

  Thereby, for example, when manufacturing a solar cell panel, in a generally known method of manufacturing a solar cell panel, the solar cell and the interconnector are in contact by pressing the solar cell and the interconnector. It has been necessary to have a redundant design that achieves the margin of junction conditions by various methods such as stabilizing the surface or supplying power larger than appropriate power. However, in such redundant design, there is a problem that the solar battery cell is damaged, such as damage to the solar battery cell. With respect to such a problem, according to the above-described embodiment, since the interconnector 1 has the welding point 3 and the recess 4, for example, the manufacturer does not need such redundant design. The connector 1 and the solar battery cell 2 can be stably joined.

  Next, the upper surface of the welding surface 6 shown in FIG. 3 desirably has a flat surface or a substantially flat surface. The reason is that it is desirable that the upper surface of the welding surface 6 be uniform at all welding points 3 when welding.

  Further, the upper surface of the welding surface 6 may adopt a configuration in which the size (area) of the welding surface 6 is determined in accordance with, for example, the tip shape of the parallel gap electrode. FIG. 5 shows an interconnector 1 having a first bonding structure according to the first embodiment of the present invention, and a parallel gap electrode having parallel gap electrodes 208 (208a, 208b) having a thin tip at the solar battery cell 2. The aspect which welds using the welding apparatus 204 is shown. In FIG. 5, the length of the welding surface 6 in the ± X direction (longitudinal direction) may be shortened according to the tip shape (that is, the size of the tip) of the parallel gap electrode 208 whose tip is formed thin. . That is, as shown in FIG. 5, the size of the welding surface 6 may be reduced according to the shape of the tip of the parallel gap electrode 208. In that case, the tip shape of the parallel gap electrode 208 may be thin enough to maintain a desired welding strength. Further, the size of the welding surface 6 may be increased.

  Next, the side surface 7 (7 a, 7 b) shown in FIG. 3 is formed perpendicular or substantially perpendicular to the welding surface 6.

  In addition, in the restraint state where the starting point of welding has already been welded, the stress generated when newly welding another welding point different from the starting point (hereinafter, in the present application, “other welding points different from the starting point "The stress generated when welding to the surface" is simply referred to as "stress". The relaxation effect of the side surface 7 differs depending on the length in the ± Z direction (longitudinal direction). Therefore, it is desirable that the length be greater. That is, as for the recessed part 4, it is desirable for the depth of a recessed to be formed deeper.

  Further, in the above-described embodiment, for convenience of explanation, the side surface 7 has been described as an example of a configuration formed perpendicular or substantially perpendicular to the welding surface 6 as an example. However, the embodiment according to the present invention is not limited to such a configuration.

  FIG. 6 is a cross-sectional view (AA cross-sectional view in FIG. 2) showing the interconnector 1 having the third bonding structure in the first embodiment of the present invention. The side surface 7 has, for example, a shape (hereinafter referred to as a “tapered shape”) in which the side surface 7a and the side surface 7b facing each other (oppositely) are inclined symmetrically (that is, line symmetrical in the Z axis direction) as shown in FIG. The formed configuration may be adopted. Thereby, the recessed part 4 can absorb stress more. Furthermore, the recess 4 may have a configuration formed by the bottom surface of the welding surface 6 having the curvature described in FIG. 4 and the side surface 7 formed in the tapered shape described in FIG. Thereby, the recessed part 4 can reduce the generation rate of the crack which generate | occur | produces at the time of welding.

  In the embodiment described above, for convenience of explanation, the interconnector 1 has been described by way of example of a configuration in which five welding points 3 (3a, 3b, 3c, 3d, 3e) are provided on the same line. However, the embodiment according to the present invention is not limited to such a configuration.

  FIG. 7 is a top view showing the main part of the interconnector 1 having the fourth bonding structure in the first embodiment of the present invention. For example, as shown in FIG. 7, the interconnector 1 adopts a configuration in which five welding points 3 (3a, 3b, 3c, 3d, 3e) are provided in a staggered manner (hereinafter referred to as "staggered arrangement") May be Thereby, the interconnector 1 can obtain desired welding strength in a smaller welding area. The reason is that the interconnector 1 can reduce the welding area in the ± X direction shown in FIG. Further, for example, in the interconnector 1, the five welding points 3 (3a, 3b, 3c, 3d, 3e) may not be provided on the same line.

  As described above, according to the first to fourth joining structures according to the present embodiment, less welding energy can be obtained without being affected by the variation in the restraint state of the welding point already welded without expanding the welding area. Can be welded. The reason is as described below.

  That is, the interconnector 1 has a start point already welded and restrained by, for example, having a recess 4 including another welding point (welding point 3b) different from the starting point close to the starting point (welding point 3a) This is because even if it is different, other welding points 3b can be welded in a stress free state where the restraint state is relieved. That is, the interconnector 1 can absorb welding distortion in the horizontal direction of the solar battery cell 2 (material to be welded).

  For example, it is predicted that the interconnector 1 is mechanically stressed by an assembly process at the time of manufacturing a solar cell panel, a temperature change in the surrounding environment when the solar cell panel is installed in a house after production, and the like Be done. However, since the interconnector 1 has the recess 4, such stress can be absorbed. That is, the interconnector 1 has a shape that is strong against such stress.

  For example, when welding the welding point 3b in the restraining state in which the welding point 3a is already welded, the balance between the welding point 3a side in the restraining state and the welding point 3c side in the stress free state not in the restraining state Are in different states. Therefore, in the interconnector without the recess 4, when the parallel gap electrode is pressed against the welding point 3b, floating of the interconnector and internal stress are accumulated. That is, in the interconnector without the recess 4, welding defects occur because of the influence of the restraint state.

  On the other hand, the interconnector 1 described in the present embodiment has the recess 4. Therefore, in the relevant interconnector 1, the side surface 7 of the recess 4 deforms, for example, in the ± X direction and the ± Y direction shown in FIG. 3, the stress generated when the interconnector 1 is deformed in such a constrained state. It is because it can absorb. Also, for example, the manufacturer can weld without being affected by such restraint. That is, the manufacturer can keep the welding quality constant (substantially constant) by using the interconnector 1.

  Moreover, the interconnector 1 can make the welding area including all the welding points small.

  The reason is that such an interconnector 1 can avoid the influence of the restraint state because it has the recess 4 including the welding point 3. Therefore, the interconnector 1 does not need to have a sufficient space between the welding point 3a and the welding point 3b in the vertical direction or the lateral direction with respect to the welding point 3a, for example, so the welding area should be small. Can. Further, in the interconnector 1, the concave portions 4 including the welding points 3 can be arranged in a staggered manner. Furthermore, it is because the welding surface 6 of the recessed part 4 can determine the magnitude | size (area) which makes the welding surface 6 according to the front-end | tip shape of a parallel gap electrode.

  As a result, for example, when manufacturing a solar cell panel, the area of the electrode of the solar cell having a welding point can be reduced. That is, as the area of the electrode decreases as the solar cell panel, the area available as the solar cell can be made larger.

  Also, for example, the manufacturer can join the materials to be welded more reliably by small welding energy. That is, the manufacturer can stably obtain higher welding quality.

  The reason is that the interconnector 1 has the recess 4 so that the side surface 7 of the recess 4 is formed vertically or substantially perpendicular to the welding surface 6 around the welding point 3. That is, since the heat generated at the time of welding hardly escapes, not only the heat generation efficiency is raised but also the bonding property is improved. Further, even if the welding energy is the same, the calorific value generated when welding is increased as the bonding area between the interconnector 1 and the solar battery cell 2 is reduced. That is, by adopting a surface having a curvature on the bottom surface of welding surface 6, the bonding area between interconnector 1 and solar battery cell 2 is reduced. Therefore, the manufacturer can weld with small welding energy.

  Furthermore, when setting (setting) when conveying, storing, welding and welding the interconnector 1, the relevant interconnector 1 can suppress the deformation of the interconnector 1 and the welding point 3 and the floating of the interconnector 1. it can. Also, for example, the manufacturer can accurately position when welding.

  The reason is that the interconnector 1 is different from Patent Document 2 in which the weld points are separated from the interconnects in a comb shape, and the weld points 3 are not separated from the interconnector 1.

Second Embodiment
Next, a second embodiment based on the bonding structure according to the above-described first embodiment of the present invention will be described. In the following description, characteristic parts according to the present embodiment will be mainly described. In that case, about the same composition as each embodiment mentioned above, the overlapping explanation is omitted by attaching the same reference number.

  An interconnector 8 having a first joint structure according to a second embodiment of the present invention will be described with reference to FIGS. 8 to 10.

  FIG. 8 is a diagram illustrating an aspect in which the interconnector 8 having the first bonding structure and the plurality of solar cells 2 (2a, 2b) according to the second embodiment of the present invention are connected.

  For convenience of explanation and illustration, interconnector 8 and solar battery cell 2 which are not shown in FIG. 8 are, for example, a plurality of interconnectors 8 and solar battery cells 2 in the ± Y direction and ± X direction shown in FIG. And have.

  In FIG. 8, the interconnector 8 electrically connects the N electrode 5 of the solar battery cell 2 a and the P electrode 9 of the solar battery cell 2 b.

  FIG. 9 is a cross-sectional view (cross-sectional view taken along the line B-B in FIG. 8) showing the interconnector 8 having the first bonding structure according to the second embodiment of the present invention.

  In FIG. 9, the recess 4 provided on one surface of the interconnector 8 (material to be welded) is connected to the N electrode 5 provided on the surface of the solar battery cell 2a in the + Z direction. Moreover, the recessed part 4 provided in the other surface different from one surface of the interconnector 8 (material to be welded) is connected with the P electrode 9 provided in the surface of the solar cell 2b in the -Z direction.

  In the embodiment described above, for convenience of explanation, the configuration in which the recess 4 of the interconnector 8 is provided on the surface (that is, both surfaces) of the interconnector 8 in the ± Z direction has been described as an example. However, the embodiment according to the present invention is not limited to such a configuration.

  FIG. 10 is a cross-sectional view (cross-sectional view taken along the line BB in FIG. 8) showing the interconnector 8 having the first bonding structure in the second embodiment of the present invention. The recess 4 of the interconnector 8 may be provided on one surface of the interconnector 8 as shown in FIG. That is, the interconnector 8 may adopt a configuration in which the recess 4 is not provided on the other surface different from the one surface. In other words, in the interconnector 8, the solar battery cells 2 a and the solar battery cells 2 b adjacent to each other are electrically connected.

  In that case, even if interconnector 8 has already been welded and constrained with P electrode 9 of solar battery cell 2b and interconnector 8, solar battery cell 2a in the stress-free state in which the restricted state is reduced. The N electrode 5 and the recess 4 can be welded.

  As described above, according to the first bonding structure according to the present embodiment, the effects described in the first embodiment can be obtained, and the shapes of the interconnector 8 are different as shown in FIGS. 9 and 10. Even in this case, the interconnector 8 and the solar battery cell 2 can be welded without being affected by the variation in the restraint state of the welding point already welded.

  The reason is that the interconnector 8 has, for example, the recess 4 so that other welds different from the start point close to the start point, for example, even if the start point (welding point 3a) is already welded and restrained. This is because the point (welding point 3b) can be welded in a stress free state in which the restraint state is reduced.

Third Embodiment
Next, a third embodiment based on the bonding structure according to the above-described first embodiment of the present invention will be described. In the following description, characteristic parts according to the present embodiment will be mainly described. In that case, about the same composition as each embodiment mentioned above, the overlapping explanation is omitted by attaching the same reference number.

  An interconnector 10 having a fifth bonding structure according to a third embodiment of the present invention will be described with reference to FIGS. 2 and 11.

  FIG. 11 is a cross-sectional view (AA cross-sectional view in FIG. 2) showing the interconnector 10 having the fifth bonding structure according to the third embodiment of the present invention.

  The interconnector 10 has a welding point 3 and a recess 11 provided in a concave shape so as to surround the vicinity of the welding point 3 on at least one surface of the interconnector 1 (material to be welded). That is, the interconnector 1 has the welding point 3 and the recess 11 provided in the vicinity of the welding point 3 so as to surround the periphery of the welding point 3.

  More specifically, the upper surface of the recess 11 has a protrusion 12 formed in a semicircle or a substantially semicircle in the + Z direction shown in FIG. That is, on the upper surface of the recess 11, a protrusion 12 formed in a convex shape in the + Z direction shown in FIG. 11 is provided.

  As described above, according to the fifth bonding structure of the present embodiment, the effects described in the first embodiment can be obtained, and welding can be performed more quickly and with less welding energy.

  The reason is that the recess 11 of the interconnector 10 has a protrusion formed in a semicircle or a substantially semicircle in the + Z direction shown in FIG. Therefore, the interconnector 10 does not have to change the shape of the bottom surface of the welding surface 6. In addition, current generated at the time of welding is concentrated on the protrusion formed in the recess 11. Thus, for example, the manufacturer can weld the interconnector 10 more quickly and with less welding energy. That is, the interconnector 10 can improve the heat generation efficiency at the time of welding without changing the contact area where the interconnector 10 (material to be welded) and the solar battery cell (material to be welded) contact with each other. .

DESCRIPTION OF SYMBOLS 1 interconnector 2 2a 2b solar battery cell 3 3a 3b 3c 3d welding point 4 recess 5 N electrode 6 welding surface 7, 7a 7b side surface 8 interconnector 9 P electrode 10 interconnector 11 recess 12 Protrusions 201, 201a, 201b Parallel gap electrodes 202 Solar cells 203 Interconnectors 204 Parallel gap welding devices 208, 208a, 208b Parallel gap electrodes

Claims (9)

One or more welding points for electrically connecting a material to be welded and another material to be welded different from the material to be welded;
The at least one surface of the material to be welded has a recess provided so as to surround the vicinity of the vicinity of the welding point,
The recess is
The welding surface includes the welding point, and the side surface provided at the end of the welding surface, and the upper surface of the welding surface is:
It has a shape having a protrusion formed in a semicircle or substantially semicircle,
The bottom of the welding surface is
Junction structure that comprises said other workpieces and the horizontal or substantially horizontal shape. The joint structure according to claim 1, wherein a bottom surface of the recess and a welding point of the other workpiece are in contact with each other. Said side is
The shape according to any one of claims 1 and 2, characterized in that it has a shape provided either vertically or substantially vertically from the welding surface, or a shape in which the two opposite side surfaces are symmetrically inclined. Junction structure. The welding surface is
The size of the welding surface is determined according to the shape of the welding electrode used when welding the workpiece and the other workpiece. Bonding structure described. The joint structure according to any one of claims 1 to 4, wherein a plurality of the welding points and the concave portion arranged in a row are provided in a zigzag shape. The joint structure according to claim 1, further comprising the recess on another surface different from the one surface of the workpiece. The joint structure according to claim 6, wherein the other material to be welded and the other material to be welded adjacent to each other on the other surface are electrically connected. A metal lead comprising the bonding structure according to any one of claims 1 to 7. Providing one or more welding points electrically connecting the material to be welded and another material to be welded different from the material to be welded;
A recess is provided on at least one surface of the material to be welded so as to surround the vicinity of the welding point,
In the recess provided,
A welding surface including the welding point and a side surface provided at an end of the welding surface are provided on the upper surface of the welding surface.
Providing a shape having a protrusion formed in a semicircle or substantially semicircle,
The bottom of the welding surface is
The use and the workpieces having said other of said one or more welding points and the recess provided the material to be welded and the horizontal or substantially horizontal shape, a parallel gap resistance welding and the other workpieces Joining at one or more welding points.

Images