Search

EP-4742376-A1 - BATTERY MODULE AND METHOD OF MANUFACTURING THE SAME

EP4742376A1EP 4742376 A1EP4742376 A1EP 4742376A1EP-4742376-A1

Abstract

The present disclosure relates to a battery module (10). More specifically, the present disclosure relates to a battery module (10) with a reinforced welding structure of a case (300) accommodating a cell assembly (100). According to an embodiment of the present disclosure, the battery module (10) with an improved welding quality of the case (300) accommodating the cell assembly (100) can be provided. The battery module (10) according to the present disclosure connects and assembles the case (300) and a bus bar assembly (200) using a fixing module (220) with an adjustable length, and hence can manage a welding gap between a pressurizing case (310) and an insertion case forming the case (300).

Inventors

  • KIM, JIN KWAN

Assignees

  • SK On Co., Ltd.

Dates

Publication Date
20260513
Application Date
20250626

Claims (15)

  1. A battery module (10) comprising: a cell assembly (100) including battery cells (111), the battery cells (111) being stacked in a front-rear direction; a case (300) accommodating the cell assembly (100); and one or more bus bar assemblies (200) accommodated in the case (300) and connected to the case (300), wherein the case (300) includes a pressurizing case (310) which faces the cell assembly (100) in the front-rear direction, wherein each of the one or more bus bar assemblies (200) includes: a bus bar (210) extending in the front-rear direction; and a fixing module (220) which is fastened to the bus bar (210) and the pressurizing case (310) to adjust a distance between the bus bar (210) and the pressurizing case (310).
  2. The battery module (10) of claim 1, wherein the fixing module (220) includes: a fixing nut (221) coupled to the bus bar (210); and a fixing bolt (222) rotatably coupled to the fixing nut (221), wherein the fixing nut (221) forms a stepped shape.
  3. The battery module (10) of claim 2, wherein the fixing nut (221) includes: a fixing nut body (2211); and a fixing nut outer rotation portion (2212) extending from the fixing nut body (2211) and having a diameter less than the fixing nut body (2211).
  4. The battery module (10) of claim 2 or 3, wherein the fixing bolt (222) is coupled to a fixing nut through hole (2213) which axially penetrates the fixing nut (221).
  5. The battery module (10) of claim 4, wherein the fixing bolt (222) includes: a fixing bolt rotation portion (2222) coupled to the fixing nut through hole (2213); and a fixing bolt body (2221) axially extending from the fixing bolt rotation portion (2222), wherein the fixing bolt (222) has a stepped shape.
  6. The battery module (10) of claim 5, wherein the fixing bolt body (2221) has a diameter greater than the fixing bolt rotation portion (2222).
  7. The battery module (10) of any one of claims 1 to 6, wherein the bus bar (210) includes: a bus bar case (211): and a nut mounting space (212) formed in the bus bar case (211), wherein the fixing module (220) is accommodated in the nut mounting space (212).
  8. The battery module (10) of claim 7, wherein the bus bar (210) further includes a bolt through hole (213) formed in the bus bar case (211), wherein the bolt through hole (213) communicates with the nut mounting space (212), and wherein the fixing module (220) passes through the bolt through hole (213).
  9. The battery module (10) of any one of claims 1 to 6, wherein the pressurizing case (310) includes: a first pressurizing case (310A) forming a front face of the battery module (10); and a second pressurizing case (310B) forming a rear face of the battery module (10).
  10. The battery module (10) of claim 9, wherein each of the first pressurizing case (310A) and the second pressurizing case (310B) includes: a pressurizing case plate (311); and a pressurizing case plate hole (312) formed in the pressurizing case plate (311), wherein the fixing bolt (222) passes through the pressurizing case plate hole (312).
  11. The battery module (10) of any one of claims 1 to 6, wherein the cell assembly (100) includes: a plurality of sub-cell groups (110) each including the battery cells (111); and a pad (120) arranged between the plurality of sub-cell groups (110).
  12. The battery module (10) of any one of claims 1 to 6, wherein the fixing module (220) is symmetrically arranged on two sides of the bus bar (210) along the front-rear direction.
  13. The battery module (10) of any one of claims 1 to 6, wherein the bus bar assemblies (200) include: a first bus bar assembly (201) arranged on a side of the cell assembly (100); and a second bus bar assembly (202) arranged on another side of the cell assembly (100).
  14. A method of assembling a battery module (10) comprising: arranging a cell assembly (100) including battery cells (111) stacked in a front-rear direction; arranging a pressurizing case (310) forming a case (300) accommodating the cell assembly (100); arranging a bus bar assembly (200) in the case (300) along the front-rear direction; and adjusting a distance between the bus bar assembly (200) and the case (300) using the bus bar assembly (200), wherein the bus bar assembly (200) includes a bus bar (210) extending in the front-rear direction; and a fixing module (220) which is fastened to the bus bar (210) and the pressurizing case (310) to adjust a distance between the bus bar (210) and the pressurizing case (310).
  15. The method of claim 14, further comprising, after arranging the bus bar assembly (200) in the case (300), arranging an insertion case forming the case (300) accommodating the cell assembly (100), wherein adjusting the distance between the bus bar assembly (200) and the case (300) is terminated when the insertion case and the pressurizing case (310) are in contact with each other.

Description

TECHNICAL FIELD The present disclosure relates to a battery module. BACKGROUND In a process of assembling a battery module, in order to secure the life of a cell assembly forming the battery module and to absorb a tolerance of the cell assembly, a pad that can be arranged between a plurality of cells forming the cell assembly need to be compressed to a certain degree. The process of assembling the battery module may include arranging a front case and a rear case at the front and rear of the stacked cell assembly, fixing the front case and the rear case with clamps, and fitting an upper case and a lower case in the above state. In a process of welding and coupling the front and rear cases and the upper and lower cases, if a welding gap between the cases increases, a welding quality may deteriorate and a welding strength may not be sufficient. SUMMARY The present disclosure relates to a battery module with an improved welding quality of a case accommodating a cell assembly. The present disclosure relates to a battery module which manages a welding gap between a pressurizing case and an insertion case forming a case by connecting and assembling the case and a bus bar assembly using a fixing module with an adjustable length. A battery module according to an embodiment of the present disclosure may comprise a cell assembly including battery cells, the battery cells being stacked in a front-rear direction; a case accommodating the cell assembly; and one or more bus bar assemblies accommodated in the case and connected to the case. The case may include a pressurizing case which faces the cell assembly in the front-rear direction. Each of the one or more bus bar assemblies may include a bus bar extending in the front-rear direction; and a fixing module which is fastened to the bus bar and the pressurizing case to adjust a distance between the bus bar and the pressurizing case. The fixing module may include a fixing nut coupled to the bus bar, and a fixing bolt rotatably coupled to the fixing nut. The fixing nut may form a stepped shape. The fixing nut may include a fixing nut body, and a fixing nut outer rotation portion extending from the fixing nut body and having a diameter less than the fixing nut body. The fixing bolt may be coupled to a fixing nut through hole which axially penetrates the fixing nut. The fixing bolt may include a fixing bolt rotation portion coupled to the fixing nut through hole, and a fixing bolt body axially extending from the fixing bolt rotation portion. The fixing bolt may have a stepped shape. The fixing bolt body may have a diameter greater than the fixing bolt rotation portion. The bus bar may include a bus bar case, and a nut mounting space formed in the bus bar case. The fixing module may be accommodated in the nut mounting space. The bus bar further may include a bolt through hole formed in the bus bar case, and the bolt through hole may communicate with the nut mounting space. The fixing module may pass through the bolt through hole. The pressurizing case may include a first pressurizing case forming a front face of the battery module, and a second pressurizing case forming a rear face of the battery module. Each of the first pressurizing case and the second pressurizing case may include a pressurizing case plate, and a pressurizing case plate hole formed in the pressurizing case plate. The fixing bolt may pass through the pressurizing case plate hole. The cell assembly may include a plurality of sub-cell groups each including the battery cells, and a pad arranged between the plurality of sub-cell groups. The fixing module may be symmetrically arranged on two sides of the bus bar along the front-rear direction. The bus bar assemblies may include a first bus bar assembly arranged on a side of the cell assembly, and a second bus bar assembly arranged on another side of the cell assembly. A method of assembling a battery module according to an embodiment of the present disclosure may comprise arranging a cell assembly including battery cells stacked in a front-rear direction; arranging a pressurizing case forming a case accommodating the cell assembly; arranging a bus bar assembly in the case along the front-rear direction; and adjusting a distance between the bus bar assembly and the case using the bus bar assembly. The bus bar assembly may include a bus bar extending in the front-rear direction; and a fixing module which is fastened to the bus bar and the pressurizing case to adjust a distance between the bus bar and the pressurizing case. The method may further comprise, after arranging the bus bar assembly in the case, arranging an insertion case forming the case accommodating the cell assembly. Adjusting the distance between the bus bar assembly and the case may be terminated when the insertion case and the pressurizing case are in contact with each other. According to an embodiment of the present disclosure, there can be provided a battery module with an improved welding quali