Patent Application
20210167468
The technology disclosed herein relates to a power storage component module, specifically to a structure for connecting power storage component to one another.
An example of a power storage component module that includes power storage components disclosed in Patent Document 1 has been known. In the power storage component module, each of battery packs includes electric terminals and bus bars. The electric terminals include upper surfaces that are flat and defined as electrode surfaces. The bus bars formed from plates. Each bus bar has a rectangular shape. The battery packs are arranged such that adjacent electric terminals have opposite polarities. A wire module is attached to surfaces on which the electric terminals are disposed. The bus bars and the electric terminals disposed inside the wire module are electrically connected by laser welding portions of the bus bars placed over the electrical terminals to the electric terminals.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2016-100248
According to the technology, the electric terminals must have surface contact with the bus bars. If vertical positions of the surfaces of the adjacent battery packs on which the electric terminals are disposed are different from each other due to dimensional differences within tolerance, the bus bars need to be forcedly brought into surface contact with the electric terminals for joint. This may result in plastic deformation of the bus bars.
A power storage component module according to the technology described herein includes a first power storage component, a second power storage component, and a bus bar. The first power storage component is disposed with an electrode of the first power storage component facing up. The second power storage component is disposed with an electrode of the second power storage component facing up. The bus bar connects the first power storage component and the second power storage component together. The first power storage component includes a positioning boss projecting upward from the electrode of the first power storage component. The bus bar includes: a through hole opening in a top-bottom direction and through which the positioning boss is passed; and a support projection projecting downward, the support projection being disposed on the electrode of the first power storage component. The support projection is electrically connected to the electrode of the first power storage component via a joint between the support projection and the electrode. The joint and the positioning boss are aligned when viewed from above.
According to the configuration, the bus bar can be positioned relative to the positioning boss by passing the positioning boss through the through hole and placing the support projection on the electrodes. When the support projection is place on the electrode, the bus bar tilts due to its own weight and contacts the electrodes. According to the configuration, even if a difference in vertical position is present between the electrode of the first power storage component and the electrode of the second power storage component, the bus bar is disposed on the electrodes at an angle regardless of the difference. Therefore, the bus bar is less likely to deform and thus the durability of the bus bar is ensured. Further, the joint and the positioning boss are aligned when viewed from above, that is, a position at which the joint is formed can be determined based on the positioning boss.
Preferable embodiments of the technology described herein may have the following configurations.
(1) The support projection may include a distal end that is aligned with the positioning boss. The electrode may include a holding section on which the distal end is disposed. The joint may include the distal end and the holding section.
According to the configuration, to form the joint, positions of the distal end and the holding section are determined based on the positioning boss and a portion in which the joint is to be formed is defined based on the positions.
(2) The distal end may have a linear shape. The bus bar may include a V-shaped groove in an upper surface of the bus bar over the supporting projection. The V-shaped groove may be recessed to form a V shape when viewed from a side. The V-shaped groove may include a groove bottom having a linear shape. The groove bottom may overlap the distal end in the top-bottom direction.
According to the configuration, the position of the distal end can be determined from above based on detection of the groove bottom from above. Therefore, the portion in which the joint is to be formed can be determined as a linear portion, that is, an area in which joining is performed can be reduced. Further, the V-shaped groove and the support projection are formed by bending the bus bar so that the distal end projects downward. This reduces a process cost.
(3) The support projection may have a spherical dome shape. The support projection may include a spherical dome recess having a spherical shape in an upper surface of the bus bar. The spherical dome recess may be concentric with the support projection.
According to the configuration, the lowest section of the support projection is the distal end. Further, the distal end and the lowest section of the spherical dome recess are aligned in the top-bottom direction. Therefore, a position of the lowest section on the upper surface side can be determined as a position of the distal end. From the determination, the area in which joining is performed can be determined.
According to the technology disclosed herein, durability of the bus bar improves.
A first embodiment will be described with reference to
This embodiment relates to a power storage component module 1 to be installed in a vehicle. As illustrated in
As illustrated in
The first power storage component 10 includes a positioning boss 20 for positioning the bus bar 30 relative to the electrode 12. The positioning boss 20 is made of a conductive metal material. The positioning boss 20 protrudes upward from the electrode 12. The positioning boss 20 includes a base end 20B and an upper end 20D. The base end 20B has a round shape in a top view. The upper end 20D has a round shape that is concentric with the base end 20B. The positioning boss 20 has a truncated cone shape with a diameter that slightly decreases from the base end 20B toward the upper end 20D. The second power storage component 110 includes an electrode 12 that has an opposite polarity from a polarity of the electrode of the first power storage component 10. Other configurations of the second power storage component 110 are similar to those of the first power storage component 10 and thus will not be described.
As illustrated in
The bus bar 30 is made of a conductive metal material such as copper and aluminum. As illustrated in
Specifically, as illustrated in
As illustrated in
Each bent portion 50 includes a top surface that is recessed downward to form V-shaped grooves 51. The V-shaped grooves 51 include groove bottoms 51A that linearly extends in the right-left direction from the middle points of the corresponding linear hole edge sections 41S with respect to the front-rear direction to right and left side edges 30S of the bus bar 30, respectively. Each bent portion 50 includes a lower surface that projects downward to form elongated projections that are defined as support projections 52. The support projections 52 include upper ends 20D that extend in the right-left direction. As illustrated in
As illustrated in
The electrode 12 of the first power storage component 10 and the electrode surface 12A of the second power storage component 110 are at different vertical positions as described below. Therefore, as illustrated in
In the situation described above, the power storage components 10 and 110 are displaced from each other in the vertical direction. In this embodiment, each positioning boss 20 has a truncated cone shape and each through hole 40 has the oval shape that is elongated in the arrangement direction of the through holes 40. Therefore, deviations of the power storage components 10 and 110 in the right-left direction and the front-rear direction are allowed.
As illustrated in
As illustrated in
Next, an example of procedure of forming the joints 70 will be described. First, the bus bar 30 is disposed on the electrode surfaces 12A of the first power storage component 10 and the second power storage component 110 held in a module case, which is not illustrated. When the positioning bosses 20 are passed through the respective through holes 40, the bus bar 30 is sloped downward toward the rear with its own weight. According to the configuration, the distal ends 52A of the support projections 52 are disposed on the electrode surfaces 12A with the distal ends 52A in contact with the electrode surfaces 12A for entire dimensions in the right-left direction regardless of a difference in vertical position between the electrode surfaces 12A.
Next, positions of the distal ends 52A of the support projections 52 are determined. First, an existing area in which the upper ends 20D of the positioning bosses 20 are present is detected by a detector, which is not illustrated. Then, an area obtained by expanding the existing area in the right-left direction by the width of the bus bar is defined as a possible existing area in which the distal ends 52A may be present. Positions of the groove bottoms 51A of the V-shaped grooves 51 in the possible existing area are detected and determined as positions of the distal ends 52A. Areas that extend in the right-left direction to pass the positions are determined as laser application areas.
If the vertical positions of the electrode surfaces 12A are different from each other, axes 52X of the support projections 52 are slightly tilted toward the rear relative to normal lines 12X (see
The laser application areas are linearly scanned with laser spotlight, which is not illustrated, in the right-left direction from the top. As described earlier, the distal ends 52A of the support projections 52 contact the electrode surfaces 12A for entire dimensions in the right-left direction because of the weight of the bus bar 30. Therefore, it is not necessary to press the distal ends 52A against the electrode surfaces 12A and thus the bus bar 30 is less likely to be deformed during forming of the joints 70.
As illustrated in
In the laser application areas, if distances between the linear hole edge sections 41S and the peripheries 20R of the respective positioning bosses 20 are within a range for the laser welding, the surfaces of the liner hole edge sections 41S are welded to the peripheries 20R of the respective positioning bosses 20. Through the welding, the supplemental joints 60 are formed. As illustrated in
The power storage component module 1 includes the first power storage component 10, the second power storage component 110, and the bus bar 30. The first power storage component 10 and the second power storage component 110 are disposed with the electrodes 12 on the upper side. The bus bar 30 connects the first power storage component 10 and the second power storage component 110 together. The first power storage component 10 includes the positioning boss 20 that protrudes upward from the electrode 12. The bus bar 30 includes the through hole 40 that opens in the top-bottom direction and through which the positioning boss 20 is passed. The bus bar 30 includes the support projection 52 that projects downward. The support projection 52 is disposed on the electrode 12 of the first power storage component 10. The joint 70 is provided between the support projection 52 and the electrode 12 of the first power storage component 10. The joint 70 electrically connects the support projection 52 to the first power storage component 10. The joint 70 and the positioning boss 20 are aligned when viewed from above.
According to the configuration, the bus bar 30 is positioned relative to the positioning boss 20 when the positioning boss 20 is passed through the through hole 40 and the support projection 52 is disposed on the electrode 12. With the support projection 52, the bus bar 30 tilts due to its own weight and contacts the electrodes 12. Even if a difference is present between the vertical position of the electrode 12 and the vertical position of the electrode of the second power storage component 110, the bus bar 30 is disposed on the electrodes 12 at an angle regardless of the difference. According to the configuration, the bus bar 30 is less likely to deform and thus the durability of the bus bar 30 is ensured. Further, the joints 70 are aligned with the positioning bosses 20. Therefore, the positions of the joints 70 are determined based on the positioning bosses 20.
The support projections 52 include the distal ends 52A that are aligned with the positioning bosses 20. The electrodes 12 include the holding sections 12B on which the distal ends 52A are placed. The joints 70 include the distal ends 52A and the holding sections 12B.
According to the configuration, to form the joints 70, the positions of the distal ends 52A and the holding sections 12B are determined based on the positioning bosses 20 and portions in which the joints 70 are to be formed are defined based on the positions.
The distal ends 52A are linear. The V-shaped grooves 51 including the groove bottoms 51A that are linear are formed in the upper surface over the support projections 52. Each V-shaped groove 51 is recessed to form the V-shape when viewed from a side. The groove bottoms 51A overlap the respective distal ends 52A in the top-bottom direction.
According to the configuration, a position 2051A of each distal end 52A can be determined from above based on detection of the corresponding groove bottom 51A from above. Therefore, the portion in which the corresponding joint is to be formed can be determined as a liner portion, that is, an area in which joint forming is performed can be reduced. Further, the V-shaped grooves 51 and the support projections 52 are formed by bending the bus bar 30 so that the distal ends 52A project downward. This reduces a processing cost.
Next, a second embodiment will be described with reference to
As illustrated in
When the power storage components 10 and 110 are connected by the bus bar 1030, as illustrated in
As illustrated in
To form each joint 1070, the lowest portion of the spherical dome recess 1051 is detected by measuring from above and the lowest portion is defined as a recess bottom 1051A (see
According to the configuration, the distal end 1052A of each support projection 1052 has a small circular shape and thus the laser application area is further limited to a smaller area. The distal end 1052A of each support projection 1052 overlaps the corresponding recess bottom 1051A in the top-bottom direction. Because the distal end 1052A of each support projection 1052 overlap the corresponding recess bottom 1051A in the top-bottom direction, the corresponding joint 1070 is properly formed through application of the laser spotlight to the laser application area.
A third embodiment will be described with reference to
As illustrated in
According to the configuration, a distal end 2052A of each support projection 2052 is movable in the front-rear direction with a center line L1 of the support projection 2052 at the middle in the front-rear direction as a center of movement in response to an angle of the bus bar 2030. Further, the distal end 2052A of each support projection 2052 is vertically aligned with the lowest position 2051A of the corresponding round recess 2051. It is not necessary to set the laser application area with margins in the front-rear direction in consideration of the positional difference.
The technology disclosed herein is not limited to the embodiments described above and illustrated in the drawings. For example, the following embodiments will be included in the technical scope of the technology.
(1) In the above embodiment, each positioning boss 20 has the truncated cone shape with the diameter that slightly decreases from the base end 20B toward the upper end 20D. However, the shape of the positioning bosses is not limited to the truncated cone shape. For example, each positioning boss may have a round columnar shape with a constant diameter from a base end toward an upper end.
(2) In the above embodiment, the positioning bosses 20 are disposed on the electrodes 12 of the power storage components 10 and 110 and the bus bar 30 includes the through holes 40. However, a configuration that includes a positioning boss disposed on one of power storage components and a bus bar including a single through hole may be included in the technical scope. With such a configuration, a position at which a joint is formed may be determined based on detection of a position of a distal end of a support projection from above or the positioning boss.
(3) In the above embodiment, the surface of the distal end 52A of each support projection 52 is welded to the holding section 12B of the corresponding electrode surface 12A to form the joint through the laser welding. However, the joint may be formed by placing a joining material such as a silver-based filler and a solder between the distal end and the holding section and forming the joint through brazing.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-112961 | Jun 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/021701 | 5/31/2019 | WO | 00 |
