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EP-4167349-B1 - BATTERY MODULE HAVING COOLING STRUCTURE USING INSULATING OIL, AND BATTERY PACK AND VEHICLE COMPRISING SAME

EP4167349B1EP 4167349 B1EP4167349 B1EP 4167349B1EP-4167349-B1

Inventors

  • JU, Eun-Ah
  • SEO, SUNG-WON
  • YUN, Hyeon-Ki
  • TANNENBERGER, Guenter
  • JANKE, JAN
  • HARASZTOSI, UWE

Dates

Publication Date
20260513
Application Date
20211109

Claims (9)

  1. A battery module comprising: a cell stack assembly (100) comprising a plurality of battery cells (110) and a plurality of fluid passage spacers (120) located between adjacent battery cells (110); a front bus bar frame assembly (200) comprising a module inlet (P1) for supplying insulating oil for cooling of the plurality of battery cells to the plurality of fluid passage spacers (120), the front bus bar frame assembly (200) being coupled to a side of the cell stack assembly (100) in a longitudinal direction of the cell stack assembly (100) to electrically connect the plurality of battery cells (110); and a rear bus bar frame assembly (300) comprising a module outlet (P2) for discharging insulating oil passing through the module inlet (P1) and the plurality of fluid passage spacers (120) to outside, the rear bus bar frame assembly (300) being coupled to the other side of the cell stack assembly (100) in the longitudinal direction of the cell stack assembly (100) to electrically connect the plurality of battery cells (110), characterized in that each of the plurality of fluid passage spacers (120) comprises: a spacer body (121) having an open central portion so that insulating oil flowing inside the fluid passage spacer (120) contacts the battery cell (110); a spacer inlet (122a) formed on a side of the spacer body (121) in a longitudinal direction of the spacer body (121) and fastened to the front bus bar frame assembly (200); and a spacer outlet (122b) formed on the other side of the spacer body (121) in the longitudinal direction of the spacer body (121) and fastened to the rear bus bar frame assembly (300), and wherein a first gasket (G1) is located at a contact interface between the spacer body (121) and the battery cell (110).
  2. The battery module of claim 1, wherein the fluid passage spacer (120) further comprises a plurality of insulating oil guides (123) configured to connect an upper end of the spacer body (121) to a lower of the spacer body (121) and spaced apart from one another in the longitudinal direction of the spacer body (121).
  3. The battery module of claim 1, wherein the front bus bar frame assembly (200) comprises: a front bus bar frame (210) formed on a surface opposite to the module inlet (P1) and comprising a front frame fastening portion (211) fastened to the spacer inlet (122a); and a front bus bar (220) provided on the front bus bar frame (210) and coupled to electrode leads (112) of the plurality of battery cells (110).
  4. The battery module of claim 3, wherein the rear bus bar frame assembly (300) comprises: a rear bus bar frame (310) formed on a surface opposite to the module outlet (P2) and comprising a rear frame fastening portion (311) fastened to the spacer outlet (122b); and a rear bus bar provided on the rear bus bar frame (310) and coupled to electrode leads (112) of the plurality of battery cells (110).
  5. The battery module of claim 4, wherein a second gasket (G2) is located between the front frame fastening portion (211) and a coupling surface of the spacer inlet (122a) and between the rear frame fastening portion (311) and a coupling surface of the spacer outlet (122b).
  6. The battery module of claim 4, further comprising a pair of side plates (400) respectively covering a pair of battery cells (110) located at both outermost positions in a stack direction of the cell stack assembly (100).
  7. The battery module of claim 6, wherein each of the pair of side plates (400) comprises a space in which insulating oil may flow, and both end portions of the side plate (400) in a longitudinal direction of the side plate (400) are respectively coupled to the front frame fastening portion (211) and the rear frame fastening portion (311).
  8. A battery pack comprising the battery module according to any one of claims 1 through 7.
  9. A vehicle comprising the battery module according to any one of claims 1 through 7.

Description

TECHNICAL FIELD The present disclosure relates to a battery module having a cooling structure using insulating oil, and a battery pack and a vehicle including the battery module, and more particularly, to a battery module having a structure in which insulating oil introduced into a module housing and cooling a battery cell may flow through an inner space of a bus bar frame into a cell stack assembly, and a battery pack and a vehicle including the battery module. BACKGROUND ART In the case of a battery module using an indirect water cooling method using cooling water, because cooling water does not directly contact a battery cell but indirectly contacts the battery cell through a module housing in which the battery cell is accommodated, there is a limit to its cooling performance. Also, because a cooling device such as a separate heat sink should be provided outside the module housing to form a passage for cooling, a volume of the battery module is inevitably increased, which may cause loss in terms of energy density. In order to solve the problems of the indirect water cooling method, there is a need to develop a battery module having a cooling structure in which insulating oil for cooling may be directly introduced into a module housing and may directly contact a battery cell. In the case of a battery module having a direct cooling structure using insulating oil, it is important to develop a fluid passage structure for efficient cooling, but it is very important to maintain airtightness so that the insulating oil does not leak to the outside of a module housing and an end plate. In the case of a battery module having a structure in which insulating oil introduced into a module housing directly contacts a battery cell, an airtight structure should be applied to various positions to prevent the insulating oil filled in the module housing from leaking to the outside of the module housing. For example, in the case of a battery module to which a mono frame with both open sides in a longitudinal direction is applied, an airtight structure should be applied to prevent leakage of oil at a coupling portion between the mono frame and an insulating plate and/or an end plate covering both opening portions of the mono frame. Also, a high-potential terminal is usually exposed to the outside of the end plate and/or the insulating plate, and because a hole through which the high-potential terminal is exposed to the outside corresponds to a position where leakage of insulating oil is likely to occur, an airtight structure should also be applied to the position. As such, applying an airtight structure to various positions complicates a process of manufacturing a battery module, which leads to an increase in manufacturing cost. Accordingly, in order to omit the application of an airtight structure to a module housing or to simplify an airtight structure for a module housing, there is a need to develop a battery module in which an airtight structure is applied to components accommodated in the module housing. KR 2019 0064887 A concerns a battery module having a heat dissipation plate. The battery module comprises a cell assembly including a plurality of secondary batteries and a plurality of heat dissipation plates interposed between the plurality of secondary. The battery module further includes bus bar assemblies, located at front and rear sides, for electrically connecting the secondary batteries to each other. The bus bar assembly includes a bus bar frame, and an insert hole is formed in the bus bar frame. The insert hole may serve as a passage through which the coolant introduced from the outside may move to the inlet portion of the heat dissipation plate. Also, the insert hole of the bus bar assembly close to the outlet portion of the heat dissipation plate may be used as a passage through which the coolant discharged from the outlet portion flows to the outside. US 2010/104927 A1 concerns a temperature-controlled battery configuration. The battery configuration includes a casing, and a plurality of alternating Lithium-ion cell packs and spacers defining vertical channels, the spacers supporting the cell packs in a hanging manner in the casing. DISCLOSURE Technical Problem The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to allowing insulating oil for cooling of a battery module to directly contact a body of a battery cell to maximize cooling efficiency and effectively prevent leakage of insulating oil which is likely to occur in this insulating oil direct contact structure. However, the technical purpose to be solved by the present disclosure is not limited to the above, and other objects not mentioned herein will be clearly understood by one of ordinary skill in the art from the following disclosure. Technical Solution In one aspect of the present invention, there is provided a battery module as defined in claim 1, including: a cell stack ass