Search

EP-4738597-A2 - BATTERY MODULE

EP4738597A2EP 4738597 A2EP4738597 A2EP 4738597A2EP-4738597-A2

Abstract

Embodiments of the present disclosure relate to a battery module. According to an embodiment of the present disclosure, there is provided a battery module including a plurality of battery cells each including at least one electrode tab, and a bus bar in contact with the electrode tabs to electrically connect the plurality of battery cells, wherein the bus bar includes a plate in which a plurality of holes are formed, and the electrode tabs are inserted into at least a portion of the plurality of holes to electrically connect the plurality of battery cells.

Inventors

  • JU, SEUNG HOON
  • KIM, KWAN YONG
  • SON, SOL SAN

Assignees

  • SK On Co., Ltd.

Dates

Publication Date
20260506
Application Date
20171222

Claims (15)

  1. A battery module comprising: a plurality of battery cells (11) each including at least one electrode tab (12); and a bus bar (20a) connected to the electrode tabs (12) to electrically connect the plurality of battery cells (11), wherein the bus bar (20a) includes a plate (21a) in which a plurality of holes (23a) are formed, wherein each of the electrode tabs (12) is inserted into one of the plurality of holes (23a) and welded to the plate (21a) such that the plate (21a) and the electrode tabs (12) are electrically connected, and wherein a width of each of the holes (23a) corresponds to a width of each of the electrode tabs (12).
  2. The battery module of claim 1, wherein the electrode tab (12) is inserted into one side of the plate (21a) and protrudes from the other side of the plate (21a).
  3. The battery module of claim 1, wherein the plate (21a, 21b) includes a protruding portion (22a, 22b) and the hole (23a, 23b) is formed in the protruding portion (22a, 22b).
  4. The battery module of claim 1, wherein the electrode tab (12) comprises a straight portion that is inserted into the hole (23a).
  5. The battery module of claim 4, wherein the plate (21a) and an end surface of the straight portion of the electrode tab are welded.
  6. The battery module of claim 4, wherein the plate (21a) and the straight portion of the electrode tab (12) are connected by a welding seam obtained by wobble laser welding, and the welding seam is obtained in that the laser is repeatedly applied to the end surface of an electrode tab (12) in a shape of a circle and centers of the circles are located along an axis (122) in a direction d2 of a length L5 of the end surface.
  7. The battery module of claim 4, wherein: the at least one electrode tab (12) includes a bent portion (121).
  8. The battery module of claim 7, wherein: the at least one electrode tab (12) includes an insulating portion (125) formed on at least a portion of the electrode tab (12); and the bent portion (121) is formed on the insulating portion (125).
  9. The battery module of claim 1, further comprising a support plate (30) in which a plurality of support holes (32) are formed, wherein the support holes (32) correspond to the holes (23a) formed in the bus bar, wherein the support plate (30) is located between the plurality of battery cells (11) and the bus bar (20a).
  10. The battery module of claim 9, wherein: a bent portion (121) is formed at the electrode tab (12); and the bent portion (121) is supported to be in contact with one side of the support hole (32).
  11. The battery module of claim 9, further comprising a fixing plate (40) in which a plurality of bus bar exposure holes (42) are formed, wherein the bus bar exposure holes (42) correspond to the holes (23a) formed in the bus bar, wherein the bus bar (20a) is located between the support plate (30) and the fixing plate (40) and is fixedly supported thereby.
  12. A method of manufacturing a battery module, comprising: providing a plurality of battery cells (11), each including at least one electrode tab (12); providing a bus bar (20a) comprising a plate (21a) having a plurality of holes (23a); inserting the electrode tabs (12) into the respective holes (23a) of the plate (21a); and welding the electrode tabs (12) to the plate (21a) while the electrode tabs (12) are in an inserted state in the holes (23a).
  13. The method of claim 12, wherein welding the electrode tabs (12) to the plate (21a) comprises laser welding.
  14. The method of claim 13, wherein the laser welding comprises wobble laser welding.
  15. The method of claim 14, wherein the wobble laser welding is performed along an axis extending in a longitudinal direction of an end surface of each electrode tab (12).

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to and the benefit of Korean Patent Application No. 10-2016-0177900, filed on December 23, 2016, Korean Patent Application No. 10-2017-0041875, filed on March 31, 2017 and Korean Patent Application No. 10-2017-0177048, filed on December 21, 2017, the disclosures of which are incorporated herein by reference in their entirety. BACKGROUND 1. Field of the Invention Exemplary embodiments of the present disclosure relate to a battery module. 2. Discussion of Related Art More powerful secondary batteries that can be charged and discharged many times are actively being researched due to their use in advanced fields such as digital cameras, cellular phones, laptop computers, hybrid vehicles, and the like. Examples of secondary batteries include a nickel-cadmium battery, a nickel-metal hydride battery, a nickel-hydrogen battery, and a lithium secondary battery. The lithium secondary battery typically has an operating voltage of 3.6 V or higher and can be used as a power source for portable electronic devices. Also, a plurality of lithium secondary batteries connected in series can be used to power a high-output hybrid vehicle. Use of the lithium secondary battery has rapidly increased because its operating voltage thereof is approximately three times higher than that of the nickel-cadmium battery or the nickel-metal hydride battery. Also, the lithium secondary battery has excellent energy density per unit of weight. Typically, a bus bar is brought into contact with the electrode tabs of battery cells for connecting a plurality of battery cells. A conventional bus bar is formed to have a C shape. Electrode tabs may be brought into contact with a C-shaped bus bar so that two or more battery cells can be electrically connected. Connecting the battery cells may require at least one of cutting and bending the electrode tabs of the battery cells. As the number of battery cells, e.g. three battery cells, four battery cells, or the like (that is, parallel connection of three cells or parallel connection of four cells) to be connected varies, the cutting and bending dimensions of electrode tabs also vary. Because existing battery modules require deforming the electrode tabs for coupling the battery cells, the number of required process operations is increased, which in turn renders the manufacturing process more complicated and increases its cost. [Document of Related Art] [Patent Document] Korean Patent Application Publication No. 10-2015-0110078 (Published on October 2, 2015) SUMMARY OF THE INVENTION Embodiments of the present disclosure provide a battery module allowing the number of assembling processes to be reduced due to electrode tab processing for electrically connecting a plurality of battery cells being simplified. Other embodiments of the present disclosure provide a battery module capable of preventing deformation of shapes of electrode tabs by a shape of a bus bar being deformed. Other embodiments of the present disclosure provide a battery module allowing costs to be reduced according to a reduction in the number of processes. Other embodiments of the present disclosure provide a battery module capable of uniformly melting electrode tabs when a plurality of battery cells are electrically connected to each other. Other embodiments of the present disclosure provide a battery module allowing a connection state to be visually confirmed when a plurality of battery cells are electrically connected by welding or the like. According to an aspect of the present disclosure, there is provided a battery module including a plurality of battery cells each including at least one electrode tab, and a bus bar in contact with the electrode tabs to electrically connect the plurality of battery cells, wherein the bus bar includes a plate in which a plurality of holes are formed, and the electrode tabs are inserted into at least a portion of the plurality of holes to electrically connect the plurality of battery cells. Each of the plurality of electrode tabs may be inserted into the corresponding one of the plurality of holes and fixed. The electrode tab may be inserted into one side of the plate and protrude to the other side of the plate. The electrode tab may protrude by a length of 1 to 3 mm from an outer end of the hole. The plate may include a protruding portion formed at a periphery of a position at which the hole is formed. A cross-section of the periphery of the hole may be formed to be tapered toward one side of the plate so that the electrode tab may be inserted into the hole. A width of an entry space into which the electrode tab enters at the one side of the plate may be reduced near the hole. The plate may include a tab connection portion configured to protrude from an outer periphery of the hole to an outside of the plate. The electrode tab and the plate may be connected to have a wobble welding shape by laser welding. The hole may be formed to