Busbar Module And Method Of Manufacturing The Same

Abstract

A busbar module includes: a busbar including an upper plate and a lower plate overlapping with the upper plate; an electrode lead positioned between the upper plate and the lower plate; and a connecting part disposed between the upper plate and the electrode lead to electrically connect the upper plate and the electrode lead, wherein a through hole is formed in the lower plate, and the connecting part is disposed at a position corresponding to the through hole.

Claims

1. A busbar module comprising: a busbar including an upper plate and a lower plate overlapping with the upper plate; an electrode lead positioned between the upper plate and the lower plate; and a connecting part disposed between the upper plate and the electrode lead to electrically connect the upper plate and the electrode lead, wherein a through hole is formed in the lower plate, and wherein the connecting part is disposed at a position corresponding to the through hole.

2. The busbar module of claim 1, wherein the connecting part comprises a material whose volume shrinks according to a temperature rise.

3. The busbar module of claim 2, wherein the material is a shape memory alloy.

4. The busbar module of claim 1, wherein the connecting part has a shape which changes according to a temperature rise.

5. The busbar module of claim 4, wherein the connecting part comprises a shape memory alloy whose shape changes according to a temperature rise.

6. The busbar module of claim 1, wherein the connecting part extends from the upper plate toward the lower plate, and the electrode lead includes a protrusion projecting into the through hole.

7. The busbar module of claim 1, wherein the electrode lead surrounds the connecting part and is at least partially inserted into the through hole.

8. The busbar module of claim 1, wherein the electrode lead is in contact with each of the connecting part and the lower plate inside the through hole.

9. The busbar module of claim 1, wherein the connecting part has a shape corresponding to a shape of the through hole.

10. The busbar module of claim 1, wherein the connecting part includes two or more connecting parts and the through hole includes two or more through holes.

11. A battery module comprising the busbar module of claim 1 and a plurality of battery cells.

12. A method of manufacturing a busbar module, comprising steps of: positioning an electrode lead between an upper plate having a protruding connecting part and a lower plate having a through hole; and fastening the upper plate and the lower plate with the electrode lead being interposed therebetween, wherein in the fastening step, the connecting part is inserted into the through hole together with the electrode lead.

13. The method of manufacturing a busbar module according to claim 12, wherein the connecting part has a shape which changes according to a temperature rise.

14. The method of manufacturing a busbar module according to claim 13, wherein the connecting part comprises a shape memory alloy whose shape changes according to a temperature rise.

15. The method of manufacturing a busbar module according to claim 12, wherein the fastening of the upper plate and the lower plate is performed through clinching joint.

16. The method of manufacturing a busbar module according to claim 12, wherein the fastening step includes compressing the upper plate and the lower plate together with the electrode lead being interposed therebetween.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] FIG. 1 is a plan view of a conventional busbar module.

[0033] FIG. 2 is a cross-sectional view of the busbar module taken along line A-A′ in FIG. 1.

[0034] FIG. 3 is an exploded perspective view of a battery module according to one embodiment of the present disclosure.

[0035] FIG. 4 is a plan view of the busbar module shown in FIG. 3.

[0036] FIG. 5 is a cross-sectional view of the busbar module taken along line B-B′ in FIG. 4.

[0037] FIG. 6 is a cross-sectional view of the busbar module taken along line C-C′ in FIG. 4.

[0038] FIG. 7 is a perspective view of the busbar of FIG. 4 before being fastened.

[0039] FIG. 8 is a cross-sectional view showing the busbar module of FIG. 6 in an abnormal operating state.

[0040] FIG. 9 is a cross-sectional view showing a busbar module according to another embodiment of the present disclosure in an abnormal operating state.

[0041] FIG. 10 is a cross-sectional view illustrating a method of manufacturing a busbar module according to an embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement them. The present disclosure may be modified in various different ways, and is not limited to the embodiments set forth herein.

[0043] Parts that are irrelevant to the description will be omitted to clearly describe the present disclosure, and like reference numerals designate like elements throughout the specification.

[0044] Further, in the drawings, the size and thickness of each element are arbitrarily illustrated for convenience of description, and the present disclosure is not necessarily limited to those illustrated in the drawings. In the drawings, the thickness of layers, regions, etc. are exaggerated for clarity. In the drawings, for convenience of description, the thicknesses of some layers and regions are exaggerated.

[0045] In addition, it will be understood that when an element such as a layer, film, region, or plate is referred to as being “on” or “above” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, it means that other intervening elements are not present. Further, the word “on” or “above” means disposed on or below a reference portion, and does not necessarily mean being disposed on the upper side of the reference portion toward the opposite direction of gravity.

[0046] Further, throughout the specification, when a part is referred to as “including” a certain component, it means that it can further include other components, without excluding the other components, unless otherwise stated.

[0047] FIG. 3 is an exploded perspective view of a battery module according to an embodiment of the present disclosure.

[0048] Referring to FIG. 3, the battery module 1000 according to the present embodiment includes a plurality of battery cells 300 and a busbar module 100 positioned on both sides of the plurality of battery cells 300. The battery module 1000 may further include a top cover 400 covering the plurality of battery cells 300.

[0049] The busbar module 100 includes an electrode lead 140 connected to the plurality of battery cells 300, a busbar 110 connected to the electrode lead 140, and a busbar frame 200 on which the busbar 110 is mounted. A slit is formed in the busbar frame 200, and the electrode lead 140 may pass through the slit to be connected to the busbar 110.

[0050] FIG. 4 is a plan view of the busbar module 100 shown in FIG. 3, wherein only the busbar 110 and the electrode lead 140 are illustrated, and the other components are not shown.

[0051] FIG. 5 is a cross-sectional view showing the busbar module along line B-B′ in FIG. 4, and FIG. 6 is a cross-sectional view showing the busbar module along line C-C′ in FIG. 4.

[0052] Referring to FIGS. 4 to 6, the busbar module 100 according to one embodiment of the present disclosure includes a busbar 110 including an upper plate 120 and a lower plate 130 overlapping with the upper plate 120; an electrode lead 140 positioned between the upper plate 120 and the lower plate 130; and a connecting part 121 disposed between the upper plate 120 and the electrode lead 140 to electrically connect the upper plate 120 and the electrode lead 140. Although not shown, the electrode lead 140 is connected to a plurality of battery cells.

[0053] A through hole 131 is formed in the lower plate 130, and the connecting part 121 is disposed at a position corresponding to the through hole 131.

[0054] Meanwhile, in FIGS. 5 and 6, although the electrode lead 140 engaged between the upper plate 120 and the lower plate 130 is illustrated to be integral, it is also possible that two or more electrode leads 140 are bent in the same direction and overlapped with each other between the upper plate 120 and the lower plate 130.

[0055] FIG. 7 is a perspective view of the busbar 110 of FIG. 4 before being fastened, wherein the electrode leads, etc. is not shown for convenience of description. As mentioned above, a through hole 131 is formed in the lower plate 130 of the busbar 110. However, although the through hole 131 is shown as a circular shape, its shape is not limited so long as it is perforated through the lower plate 130, and thus a polygonal through hole is also available.

[0056] Referring back to FIGS. 4 to 6, the connecting part 121 extends from the upper plate 120 toward the lower plate 130, and can be inserted into the through hole 131 together with the electrode lead 140, wherein the electrode lead 140 may form a structure surrounding the connecting part 121 inside the through hole 131.

[0057] Accordingly, unlike the conventional busbar module, the busbar 110 and the electrode lead 140 can be electrically connected through the mechanical fastening of the upper plate 120, the lower plate 130 and the electrode lead 140 positioned between the two plates, without being welded. That is, the electrode lead 140 includes a protrusion 141 formed due to the pressing of the connecting part 121, and the protrusion 141 forms a structure protruding into the through hole 131.

[0058] In addition, inside the through hole 131, the electrode lead 140 may be in close contact with each of the connecting part 121 of the upper plate 120 and the lower plate 130. In other words, since the contact area between the busbar 110 and the electrode lead 140 may be increased compared to a conventional welding joint, the contact resistance between the busbar 110 and the electrode lead 140 may be reduced.

[0059] Meanwhile, it is preferable that the connecting part 121 has a shape corresponding to that of the through hole 131, in order that the connecting part 121 is inserted into the through hole 131 and is in close contact with the electrode lead 140 inside the through hole 131. For example, when a circular through hole 131 is formed in the lower plate 130 as shown in FIG. 7, it is preferable that the connecting part 121 has a cylindrical shape. In addition, although not shown, when a polygonal through hole is formed, it is preferable that the connecting part has a shape of a polygonal column corresponding thereto.

[0060] Further, each of the connecting part 121 and the through hole 131 is not limited to the number thereof, but the number is preferably two or more in order to securely fasten the busbar 110 and the electrode lead 140.

[0061] FIG. 8 is a cross-sectional view showing the busbar module of FIG. 6 in an abnormal operating state.

[0062] Referring to FIG. 8, when an abnormal operating state such as an overcurrent state or a high temperature state occurs, the connecting part 121 according to the present embodiment increases in temperature, and when the temperature exceeds a certain level, its volume may shrink.

[0063] The connecting part 121 may include a material whose volume shrinks as the temperature rises, and such material may include a shape memory alloy. More specifically, the shape memory alloy may be welded with the upper plate 120 and then be nickel plated to form the connecting part 121. In a normal operating state, the electrical conductivity is maintained through the nickel plating, whereas in an abnormal operating state, the temperature rises above a certain temperature and, thus, the volume of the shape memory alloy decreases, which may lead to decrease in the volume of the connecting part 121.

[0064] In this case, the temperature at which the volume shrinkage of the shape memory alloy occurs is preferably 100 to 120 degrees Celsius to ensure safety in an abnormal operating state.

[0065] As shown in FIG. 8, since the volume of the connecting part 121 shrinks, the connection between the connecting part 121 and the electrode lead 140 becomes loose, and eventually, the connecting force between the upper plate 120 and the electrode lead 140 is reduced, so that the upper plate 120 and the electrode lead 140 may be separated from each other. In this way, the current flowing through the battery cell is cut off, thereby improving safety in an abnormal operating state.

[0066] FIG. 9 is a cross-sectional view showing a busbar module according to another embodiment of the present disclosure in an abnormal operating state.

[0067] Referring to FIG. 9, a busbar 210 including an upper plate 220 and a lower plate 230, a through hole 231 formed in the lower plate 230, and an electrode lead 240 including a protrusion 241 are equal or similar to those shown in FIG. 8, respectively, and, thus, the descriptions thereon are omitted.

[0068] However, the connecting part 221 connected to the upper plate 220 may include a material whose shape changes according to a temperature rise. For example, it may include a shape memory alloy whose shape changes as a temperature exceeds a certain level.

[0069] In particular, when the temperature of the connecting part 221 rises due to an abnormal operating state, the width of the connecting part 221 in a direction parallel to the upper plate 220 (X direction) may decrease, and the height of the connecting part 221 in a direction perpendicular to the upper plate 220 may increase. In case the connecting part 221 is cylindrical, a decrease in the width in the direction parallel to the upper plate 220 (X direction) may correspond to a decrease in the diameter of the cylinder, and an increase in the height in the direction perpendicular to the upper plate 220 (Y direction) may correspond to an increase in the height of the cylinder.

[0070] As described above, since the width in the direction parallel to the upper plate 220 (X direction) decreases, the connection between the connecting part 221 and the electrode lead 240 becomes loose, and eventually, the connecting force between the upper plate 220 and the electrode lead 240 is reduced, so that the upper plate 220 and the electrode lead 240 may be easily separated from each other. In addition, since the height in the direction perpendicular to the upper plate 220 (Y direction) increases, the connecting part 221 has an effect of pushing the upper plate 220 out of the electrode lead 240 and the lower plate 230, which may be more advantageous in blocking current.

[0071] In this regard, since the volume of the connecting part 221 is not limited, the volume of the connecting part 221 may reduce, increase, or maintain as the width decreases and the height increases.

[0072] On the other hand, the temperature at which the shape change of the shape memory alloy occurs is preferably 100 to 120 degrees Celsius to ensure safety in an abnormal operating state.

[0073] FIG. 10 is a cross-sectional view illustrating a method of manufacturing a busbar module according to one embodiment of the present disclosure.

[0074] Referring to FIG. 10, a method of manufacturing a busbar module according to one embodiment of the present disclosure includes the steps of: positioning an electrode lead 140 between an upper plate 120 having a protruding connecting part 121 formed and a lower plate having a through hole 131 formed; and fastening the upper plate 120 and the lower plate 130 with the electrode lead 140 being interposed therebetween, wherein in the fastening step, the connecting part 121 is inserted into the through hole 131 together with the electrode lead 140.

[0075] Unlike a conventional laser welding or ultrasonic welding, the coupling of the busbar 110 and the electrode lead 140 is performed through clinching joint. That is, the upper plate 120 and the lower plate 130 are compressed with the electrode lead 140 being interposed therebetween by using a punch or die of a specified size, thereby causing physical deformation, which leads to the fastening of the upper plate 120, the lower plate 130 and the electrode lead 140.

[0076] Meanwhile, the above-described structure and material may be applied to the connecting part 121 and the through hole 131, and therefore, the description thereof will be omitted because it is redundant.

[0077] A battery module including the busbar module as described above can be applied to various devices. Such devices include, but are not limited to, transportation means such as an electric bicycle, an electric vehicle, and a hybrid vehicle, and the battery module is applicable to various devices capable of using a secondary battery.

[0078] Although the preferred embodiments of the present disclosure have been described in detail above, the scope of the present disclosure is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present disclosure defined in the following claims also belong to the scope of rights.

DESCRIPTION OF REFERENCE NUMERALS AND SYMBOLS

[0079] 100: busbar module [0080] 110: busbar [0081] 120: upper plate [0082] 121: connecting part [0083] 130: lower plate [0084] 131: through hole [0085] 140: electrode lead [0086] 1000: battery module